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ASYMPTOTIC HOMOGENIZATION IN A PARABOLIC SEMILINEAR PROBLEM WITH PERIODIC COEFFICIENTS AND INTEGRABLE INITIAL DATA

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Acta Mathematica Scientia 2013年第5期33卷 1275-1292页

作者： Rogerio luiz Quintino de oliveira JUNIOR Instituto de Matema'tica e Estat' stica Universidade do Estado do R.de Janeiro Rua S ao Francisco Xavier524 - Pavilha o Reitor Joa o Lyra Filho 6oandar bl.B 20559-900 Rio de Janeiro R.J. Brazil

In this paper, we study the large time behavior of solutions of the parabolic semilinear equation δtu-div（a（x）△↓u） = -｜u｜^αu in （0,∞） × R^N, where α 〉 0 is constant and a∈ Cb^1（R^N） is a symmetric periodic matrix satisfying some ellipticity *** an integrable initial data u0 and α ∈ （2/N, 3/N）, we prove that the large time behavior of solutions is given by the solution U（t, x） of the homogenized linear problem δtU-div（a^h△↓U）=0,U（0） = C, where a^h is the homogenized matrix of a（x）, C is a positive constant and δ is the Dirac measure at 0.

关键词： homogenization similinear parabolic equation integrable initial data matrix with periodic coefficient large time behavior

Duration and intensity of rainfall events with the same erosivity change sediment yield and runoff rates

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International Soil and Water Conservation Research 2021年第1期9卷 69-75页

作者： Wilk Sampaio de Almeida Steffen Seitz luiz Fernando Coutinho de oliveira Daniel Fonseca de Carvalho Agronomy department Federal Institute of EducationScience and Technology of RondôniaCampus AriquemesRO 257km 13AriquemesRO76870-000Brazil department of Geosciences University of TübingenTübingenGermany Federal University of Lavras Department of Water Resources and Sanitation37200-000LavrasMGBrazil Federal Rural University of Rio de Janeiro Engineering DepartmentBR 465km 723897-000SeropédicaRJBrazil

The effect of different rainfall patterns on surface runoff,infiltration and thus soil losses and sediment concentrations are still in the focus of current *** most simulated rainfall experiments,pre-cipitation is applied at a fixed intensity for a fixed ***,the impact of rainfall patterns on soil erosion processes may be different varying the rainfall duration and intensity that produces an event with similar rainfall erosivity ***-five rainfall events were applied on micro-scale runoff plots in a soil covered with corn straw to evaluate the sediment yield and runoff *** different rainfall types were composed by association of duration(Dur)and intensity(IP)with the same erosivity *** Dur varied from 38 to 106 min and the IP varied from 75.0 to 44.6 mm h^(-1).The sediment yield varied from 1.89±1.26 g m^(-2) to 4.02±2.66 g m^(-2) and runoff ranged from 16.9±8.74 mm to 32.63±10.67 mm with highest rates occurring with high intensity and low *** highest rainfall intensity provides the maximum sediment yield(0.138 g m^(-2) min^(-1))and runoff rates(0.87 mm min^(-1)).The time to start surface runoff varied from 14 to 19.2 min and it was longer in treatments with longer durations and low precipitation *** difference was found in the amount of sediments applying rain with the same erosivity and different associations of duration and ***,the intensity and duration of the rain,with the same erosivity,altered the amount and time of *** rainfall experiments with con-stant intensity and fixed time,the erosion rates depend on the duration of the applied ***,the results of this study can contribute to the development of new perspectives in the design of water erosion experiments with simulated rain considering the duration,intensity and also the association of these variables to produce rainfall that delivery the same soil erosion capacity.

关键词： Simulated rainfall Rainfall pattern Water erosion Soil loss

The interplay between leaf water potential and osmotic adjustment on photosynthetic and growth parameters of tropical dry forest trees

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Journal of Forestry Research 2023年第1期34卷 177-186页

作者： Tiago de Sousa Leite Romulo Magno oliveira de Freitas Nildo da Silva Dias Jeferson luiz Dallabona Dombroski Narjara Walessa Nogueira Federal University of Mato Grosso CuiabáMTBrazil Federal Institute of Education Science and Technology of Rio Grande do NortePau dos FerrosRNBrazil Federal Rural University of the Semi-Arid Region MossoróRNBrazil

Mimosa tenuiflora and Piptadenia stipulacea are commonly accepted as drought-tolerant species but little is known about their response to drought followed by ***,the interplay between leaf water potential and osmotic adjustment on photo synthetic and growth parameters of these species was examined.A greenhouse study was conducted in a split-plot design with two water conditions in the main plots(control;drought followed by rehydration),and eight sampling times in the subplots(1,4and 7 days of drought,and 1,3,6,12,and 17 days of rehydration).Plant water status and biochemical changes were assessed as well as leaf gas exchange and subsequent *** drought stress,both species maintained a low leaf water potential throughout the day by accumulating compatible solutes,thus allowing a rapid and full recovery of water status when *** these plants minimized water loss by closing their stomata,neither showed stomatal limitations to *** inhibition of this process during drought was possibly related to mesophyll limitations as well as to a reversible downregulation of photo systems,along with adjustments of their *** deficits also triggered morphological adaptations at the whole plant level,leading to reduced growth,mainly of the shoots in *** and the roots in ***.

关键词： Drought stress Rehydration Gas exchange Plant biomass

Creeping fat and gut microbiota in Crohn’s disease

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World Journal of Gastroenterology 2025年第1期31卷 16-23页

作者： Ana EV Quaglio Daniéla O Magro Marcello Imbrizi Ellen CS de oliveira luiz C Di Stasi Ligia Y Sassaki Verum Ingredients Botucatu Technology ParkBotucatu 18605-525São PauloBrazil department of Surgery Faculty of Medical SciencesState University of CampinasCampinas 13083-970São PauloBrazil department of Gastroenterology Faculty of Medical SciencesUniversity of CampinasCampinas 13083-970São PauloBrazil department of Internal Medicine Medical SchoolSão Paulo State UniversityBotucatu 18618-686São PauloBrazil department of Biophysics and Pharmacology Institute of BiosciencesSão Paulo State UniversityBotucatu 18618-689São PauloBrazil

In this article,we explored the role of adipose tissue,especially mesenteric adipose tissue and creeping fat,and its association with the gut microbiota in the pathophysiology and progression of Crohn’s disease(CD).CD is a form of inflammatory bowel disease characterized by chronic inflammation of the gastrointestinal tract,influenced by genetic predisposition,gut microbiota dysbiosis,and environmental *** microbiota plays a crucial role in modulating immune response and intestinal inflammation and is associated with the onset and progression of ***,visceral adipose tissue,particularly creeping fat,a mesenteric adipose tissue characterized by hypertrophy and fibrosis,has been implicated in CD pathogenesis,inflammation,and *** bacteria from the gut microbiota may translocate into mesenteric adipose tissue,contributing to the formation of creeping fat and influencing CD *** creeping fat may be a protective barrier against bacterial invasion,its expansion can damage adjacent tissues,leading to *** gut microbiota through interventions such as fecal microbiota transplantation,probiotics,and prebiotics has shown potential in managing ***,more research is needed to clarify the mechanisms linking gut dysbiosis,creeping fat,and CD progression and develop targeted therapies for microbiota modulation and fat-related complications in patients with CD.

关键词： Creeping fat Mesenteric adipose tissue Gut microbiota Crohn’s disease Inflammatory bowel disease

Co-Simulation of an SRG Wind Turbine Control and GPRS/EGPRS Wireless Standards in Smart Grids

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IEEE/CAA Journal of Automatica Sinica 2021年第3期8卷 656-663页

作者： Andre luiz de oliveira Carlos Eduardo Capovilla Ivan Roberto Santana Casella JoséLuis Azcue-Puma Alfeu J.Sguarezi Filho University of Sao Paulo Sao Paulo 05508-010Brazil Federal University of ABC Santo Andre 09210-580Brazil

Wind energy can be considered a push-driver factor in the integration of renewable energy sources within the concept of smart *** its full deployment,it requires a modern telecommunication infrastructure for transmitting control signals around the distributed generation,in which,the wireless communication standards stand out for employing modern digital modulation and coding schemes for error correction,in order to guarantee the power plant *** some developing countries,such as Brazil,the high penetration of commercial mobile wireless standards GPRS and EGPRS(based on GSM technology)have captivated the interests of the energy sector,and they now seek to perform remote monitoring and control *** this context,this article presents a comparative performance analysis of a wireless control system for a wind SRG,when a GPRS or EGPRS data service is *** system performance is analyzed by co-simulations,including the wind generator dynamics and the wireless channel *** satisfactory results endorse the viability and robustness of the proposed system.

关键词： General packet radio service(GPRS)/enhanced GPRS(EGPRS) smart grids switched reluctance generator(SRG) wind energy wireless communications

Distribution of the related weevil species Sitophilus oryzae and S. zeamais in Brazil

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Insect Science 2013年第6期20卷 763-770页

作者： Alberto S. Correa luiz Orlando de oliveira Lucas S. Braga Raul Narciso C. Guedes departamento de Entomologia Universidade Federal de Vicosa Vicosa Brazil departamento de Bioquimica e Biologia Molecular Universidade Federal de Vicosa Vicosa Brazil

The genus Sitophilus （Coleoptera： Curculionidae） encompasses species of great economic importance as stored grain pests worldwide. Among these species, the maize and the rice weevils （Sitophilus zeamais and Sitophilus oryzae, respectively） are partic- ularly important in warmer climates. These two weevils exhibit closely morphological and ecological resemblance making difficult their proper identification and recognition of their distribution in grain-producing regions. Both species are recorded in South America and particularly in Brazil, but their respective distribution and prevalence were not yet assessed in the region. Therefore, several insect samples throughout Brazil were collected and subjected to morphological identification using male genitalia and also using molec- ular identification with species-specific primers designed for clear recognition of both the species. The primers were designed for the specific amplification of a gene fragment of the cytochrome oxidase subunit I, which exhibited high specificity during our prelimi- nary experiments with insects from six populations of known species （either S. zeamais or S. oryzae）. Both identification strategies provided the same results indicating preva- lence of the maize weevil S. zeamais throughout the country. Two hypotheses may explain such prevalence：（i） the likely host preference ofS. zeamais for maize because this is the most cultivated cereal in Brazil, and （ii） the prevalence ofS. zeamais in tropical regions as compared with S. oryzae, which is more disseminated in subtropical and temperate regions.

关键词： cytochrome oxidase subunit I distribution maize weevil rice weevil South America

Stepped machine learning for the development of mineral models: Concepts and applications in the pre-salt reservoir carbonate rocks

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Energy and AI 2021年第1期3卷 167-179页

作者： Lucas Abreu Blanes de oliveira luiz Felipe Niedermaier Custodio Thais Bortotti Fagundes Carina Ulsen Cleyton de Carvalho Carneiro Petrobras–Petroleo Brasileiro S.A. Avenida Henrique Valadares 28CentroRio de Janeiro20231-030 Rio de JaneiroBrazil Universidade de Sao Paulo USPEscola PolitecnicaPraça Narciso de AndradeVila MathiasSantosSão Paulo 11013-560Brazil

Understanding rock mineralogy is essential for formation evaluation,improving the calculation of porosity and hydrocarbon *** primary method to obtain the mineralogy from a well is by applying a model to the geochemical tool’s chemical ***,creating a mineralogical model presents challenges such as the minerals’chemical composition and the decision to include a mineral in the *** traditional application of machine learning can make mineral models less realistic since conventional training is developed based on a set of minerals with different occurrences,lowering some minerals’*** present research proposes the stepped machine learning(SML),a stepped way to use machine learning to create a mineralogical model from chemical and mineralogical data.A database was assembled with the elemental concentration obtained with XRF analyses and the mineral concentrations obtained with XRD *** chemical elements were Al,Ca,Fe,K,Mg,Mn,Na,Si,and *** minerals were calcite,dolomite,quartz,clays,K-feldspar,plagioclase,and *** algorithms were tested:MLP,GAN,Random Forest,and XGBoost,with XGBoost showing the best *** was applied,where a mineral model results are used to train a subsequent *** allowed for a significant improvement in some models,notably to clays with an increase in R 2 from 0.597 to 0.853,quartz an increase from 0.673 to 0.869,and calcite,from 0.758 to 0.862.A decrease in the mean squared error of these minerals’models was also *** model was applied to the geochemical logs from three wells drilled in the Brazilian pre-salt,and the results were compared with XRD *** SML model was able to honor the mineral concentrations for different *** is demonstrated that the integration between machine learning tools and geological knowledge in SML was crucial for creating a representative mineralogical model.

关键词： minerals quartz reservoir

Calibration and validation of FAO-AquaCrop model to estimate the total biomass and yacon root yield

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 123-128页

作者： Ramon Amaro de Sales Alexandre Cândido Xavier Evandro Chaves de oliveira Fábio luiz de oliveira Diego Mathias Natal da Silva Sávio da Silva Berilli departament of Plant Science Federal University of ViçosaMinas GeraisBrazil Center of Agrarian Sciences and Engineering Federal University of Espirito SantoEspírito SantoBrazil Federal Institute of Education Science and Technology of Espírito Santo-Campus ItapinaEspírito SantoBrazil Federal Institute of Education Science and Technology of Southeast Minas Gerais-Campus ManhuaçuMinas GeraisBrazil

Due to the current water scarcity in the world,it is extremely important to improve the use of this natural and exhaustible resource in agriculture,by contributing to increase agricultural production and *** models of crop growth simulation were developed to predict the edaphoclimatic effects on crop *** models are calibrated and validated for a given region using the data generated from field ***,the objective of this study was to calibrate and validate the FAO AquaCrop model for yacon(Smallanthus sonchifolius)crop in a tropical *** experiment was conducted in an experimental area located in the municipality of Ibatiba,state of Espírito Santo(Brazil)during the years of 2013 and *** calibration was done using the Autumn planting and validation with the Winter and Spring *** the statistical analysis,the coefficient of determination,Willmott concordance index,bias for the systematic error,root mean square error and the mean absolute error to test the model performance were *** general,the FAO AquaCrop model predicted the root yield,total biomass and harvest index with acceptable accuracy,and with deviations of less than 6%for total and root *** planting of yacon showed a reduction in yield as well as total biomass.

关键词： Smallanthus sonchifolius root yield simulation modelling agrometeorology

Mindfulness training in medical education as a means to improve resilience,empathy,and mental health in the medical profession

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World Journal of Psychiatry 2024年第4期14卷 489-493页

作者： Edison Iglesias de oliveira Vidal luiz Fernando Alvarenga Ribeiro Marco Antonio de Carvalho-Filho Fernanda Bono Fukushima Internal Medicine department Botucatu Medical SchoolSao Paulo State University(UNESP)Botucatu 18618-687SPBrazil Wenckebach Institute for Education and Training LEARN-Lifelong LearningEducation and Assessment Research NetworkUniversity Medical Center GroningenGroningen 9713AVGroningenNetherlands Assertiva Mindfulness Botucatu 18603-970SPBrazil Surgical Specialties and Anesthesiology department Botucatu Medical SchoolSão Paulo State University(UNESP)Botucatu 18618-687SPBrazil

The high rates of depression,burnout,and increased risk of suicide among medical students,residents,and physicians in comparison with other careers signal a mental health crisis within our *** contend that this crisis coupled with the inadequate acquisition of interpersonal skills during medical education results from the interaction between a challenging environment and the mental capital of ***,we posit that mindfulness-based practices are instrumental for the development of major components of mental capital,such as resilience,flexibility of mind,and learning skills,while also serving as a pathway to enhance empathy,compassion,self-awareness,conflict resolution,and relational ***,the evidence base supporting the effectiveness of mindfulness-based interventions has been increasing over the years,and a growing number of medical schools have already integrated mindfulness into their *** we acknowledge that mindfulness is not a panacea for all educational and mental health problems in this field,we argue that there is currently an unprecedented opportunity to gather momentum,spread and study mindfulness-based programs in medical schools around the world as a way to address some longstanding shortcomings of the medical profession and the health and educational systems upon which it is rooted.

关键词： Mindfulness Medical education Mental capital Mental health Medical students Resilience