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Pseudo-discontinuum model to simulate hard-rock mine pillars

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Underground Space 2023年第4期11卷 81-95页

作者： Erick Ro genes Alessandra dos santos Gomes Marcio Muniz de Farias Leandro lima Rasmussen Faculty of Technology University of BrasiliaDF 70910-900BrasiliaBrazil

In this study,the pseudo-discontinuum modeling technique,called continuum Voronoi block model(CVBM),was applied to repre-sent the behavior of hard-rock pillars from underground mines subjected to high field *** CVBM’s ability to produce numerical results consistent with the observed behavior of pillars is demonstrated through the numerical analysis of a hypothetical case and a back analysis of the Creighton mine *** results show that the model can capture convergence displacements and explicitly show the formation of macro-fractures parallel to excavation walls,intact rock slabs,and V-shaped *** components are characteristics of brittle failure induced by highly stressed ground *** studies presented in this work confirm the CVBM as a convenient tool for the numerical modeling of intact rock pillars excavated in deep underground mines.

关键词： Brittle failure Spalling Bulking Voronoi tessellation

A convolutional recurrent neural network for strong convective rainfall nowcasting using weather radar data in Southeastern Brazil

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Artificial Intelligence in Geosciences 2022年第1期3卷 8-13页

作者： Angelica N.Caseri leonardo Bacelar lima santos Stephan Stephany CEMADEN-Estrada Dr.Altino Bondensan 500-Eug^enio de MeloS.J.CamposBrazil INPE-Av.dos Astronautas 1758-Jardim da GranjaS.J.Campos12.227-001Brazil

Strong convective systems and the associated heavy rainfall events can trig-ger floods and landslides with severe detrimental *** events have a high spatio-temporal variability,being difficult to predict by standard meteorological numerical *** work proposes the M5Images method for performing the very short-term prediction(nowcasting)of heavy convective rainfall using weather radar data by means of a convolutional recurrent neural *** recurrent part of it is a Long Short-Term Memory(LSTM)neural *** tests were performed for the city and surroundings of Campinas,located in the Southeastern *** convolutional recurrent neural network was trained using time series of rainfall rate images derived from weather radar data for a selected set of heavy rainfall *** attained pre-diction performance was better than that given by the persistence forecasting method for different prediction times.

关键词： Nowcasting Rainfall Extreme events Weather radar Deep learning

Study of Reinforcement Distribution,Adhesion between Layers,and Porosity Induced by FDM

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材料科学与工程（中英文A版） 2021年第2期11卷 56-62页

作者： Arthur Wernke Rafael dos santos leonardo santos Manuel Barcelos Jr Emmanuel lima Laboratório Associado de Sensores e Materiais Instituto Nacional de Pesquisas Espaciais(INPE)Avenida dos Astronautas 1758São Josédos Campos-SP 12245-970Brazil Faculdade do Gama(FGA) Universidade de Brasília(UnB)St.Leste Projeção AGama-DF 72444-240Brazil

This study aims to understand the distribution of reinforcement material in the matrix,evaluate the adherence between layers,and determine the air gap between printing *** printed the specimen with two different composite materials,Polylactic Acid(PLA)reinforced with acrylic particles,and another filament reinforced with short carbon *** the observations of the samples,we used a Confocal *** estimated the porosity of the material by comparing the expected mass with that achieved after *** pixel count,after binarization,we found the average percentage of acrylate *** showed fair distribution through the PLA matrix even after the manufacturing *** determination of fibers alignment was made by binarization of image,together with k-means and edge *** combination of methods allows estimating the fiber alignment by orientation straight *** manufacturing process did not offer good alignment of the fibers,even with the filament initially well aligned.

关键词： 3D printing porosity in 3D printed parts 3D printed composite materials

Injection of bone marrow mesenchymal stem cells by intravenous or intraperitoneal routes is a viable alternative to spinal cord injury treatment in mice

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Neural Regeneration Research 2018年第6期13卷 1046-1053页

作者： Bruna dos santos Ramalho FernANDa Martins de Almeida Conrado Mendonca Sales Silmara de lima Ana Maria Blanco Martinez Laboratorio de Neurodegeneracao e Reparo Departamento de Patologia - Faculdade de Medicina HUCFF Universidade Federal do Rio de Janeiro Rio de laneiro Brazil

In spite of advances in surgical care and rehabilitation, the consequences of spinal cord injury （SCI） are still challenging. Several experimental therapeutic strategies have been studied in the SCI field, and recent advances have led to the development of therapies that may act on the inhibitory microenvironment. Assorted lineages of stem cells are considered a good treatment for SCI. This study investigated the effect of systemic transplantation of mesenchymal stem cells （MSCs） in a compressive SCI model. Here we present results of the intraperitoneal route, which has not been used previously for MSC administration after compressive SCI. We used adult female C57BL/6 mice that underwent laminectomy at the T9 level, followed by spinal cord compression for 1 minute with a 30-g vascular clip. The animals were divided into five groups： sham （anesthesia and laminectomy but without compression injury induction）, MSC i.p. （intraperitoneal injection of 8×10^5 MSCs in 500 μL of DMEM at 7 days after SCI）, MSC i.v. （intravenous injection of 8 × 10^5 MSCs in 500μL of DMEM at 7 days after SCI）, DMEM i.p. （intraperitoneal injection of 500μL of DMEM at 7 days after SCI）, DMEM i.v. （intravenous injection of 500 μL of DMEM at 7 days after SCI）. The effects of MSCs transplantation in white matter sparing were analyzed by luxol fast blue staining. The number of preserved fibers was counted in semithin sections stained with toluidine blue and the presence of trophic factors was analyzed by immunohistochemistry. In addition, we analyzed the locomotor performance with Basso Mouse Scale and Global Mobility Test. Our results showed white matter preservation and a larger number of preserved fibers in the MSC groups than in the DMEM groups. Furthermore, the MSC groups had higher levels of trophic factors （brain-derived neurotrophic factor, nerve growth factor, neurotrophin-3 and neurotrophin-4） in the spinal cord and improved locomotor performance. Our results indicate that injection of MSC

关键词： spinal cord injury mesenchymal stem cells intravenous route intraperitoneal route functional recovery systemic transplantation neural regeneration

Characterization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta leonardo Benedini Paulo Marcos Ma.Agustina Cócola Mercedes Virginia Barros Daniel Gregori leonardo Strazzere Anderson Costa dos santos Mauro C.Geraldes Instituto Geologico del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and *** particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore *** probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and *** inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%NaCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

Inositol 1,4,5-trisphosphate receptor in the liver:Expression and function

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World Journal of Gastroenterology 2019年第44期25卷 6483-6494页

作者： Fernanda de Oliveira Lemos Rodrigo M Florentino Antonio Carlos Melo lima Filho Marcone Loiola dos santos M Fatima Leite Department of Physiology and Biophysics Universidade Federal de Minas GeraisBelo HorizonteMinas Gerais 31270-901Brazil Department of Cell Biology Universidade Federal de Minas GeraisBelo HorizonteMinas Gerais 31270-901Brazil

The liver is a complex organ that performs several functions to maintain *** functions are modulated by calcium,a second messenger that regulates several intracellular *** hepatocytes and cholangiocytes,which are the epithelial cell types in the liver,inositol 1,4,5-trisphosphate(InsP3)receptors(ITPR)are the only intracellular calcium release *** isoforms of the ITPR have been described,named type 1,type 2 and type *** ITPR isoforms are differentially expressed in liver cells where they regulate distinct physiological *** in the expression level of these receptors correlate with several liver diseases and hepatic *** this review,we highlight how the expression level,modulation,and localization of ITPR isoforms in hepatocytes and cholangiocytes play a role in hepatic homeostasis and liver pathology.

关键词： Inositol 1,4,5-trisphosphate receptor Liver Calcium signaling Hepatocytes and cholangiocytes

The ARQUIGRAFIA project: A Web Collaborative for Review Only Environment for Architecture and Urban Heritage Image

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Journal of Data and Information Science 2020年第1期5卷 51-67页

作者： Vânia Mara Alves lima Ci bele Araújo Camargo Marques dos santos Artur Simões Rozestraten Department of Information and Culture University of São PauloSão PauloBrazil Department of Architecture Technology University of São PauloSão PauloBrazil

Purpose:This paper presents the ARQUIGRAFIA project,an open,public and nonprofit,continuous growth web collaborative environment dedicated to Brazilian architectural photographic ***/methodology/approach:The ARQUIGRAFIA project promotes the active and collaborative participation among its institutional users(GLAMs,NGOs,laboratories and research groups)and private users(students,professionals,professors,researchers),both can create an account and share their digitized iconographic collections in the same Web environment by uploading their files,indexing,georeferencing and assigning a Creative Commons ***:The development of users interactions by means of semantic differentials impressions recording on visible plastic-spatial aspects of the architectures in synthetic infographics,as well as by the retrieval of images through an advanced system search based on those impressions *** gamification means,the system often invites users to review images’in order to improve images’data *** pilot project named Open Air Museum that allows users to add audio descriptions to images in *** interface for users’digital curatorship will be soon *** limitations:The ARQUIGRAFIA’s multidisciplinary team gathering professorsresearchers,graduate and undergraduate students from the Architecture and Urbanism,Design,Information Science,Computer Science faculties of the University of S?o Paulo,demands continuous financial resources for grants,for contracting third party services,for the participation in scientific events in Brazil and abroad,and for *** 2016,significant budget cuts in the University of S?o Paulo own research funds and in Brazilian federal scientific agencies can compromise the continuity of this *** implications:The open source template called+GRAFIA that can freely help other areas of knowledge to build their own visual Web collaborative ***/value:The collaborative natu

关键词： Metadata Architectural images Collaborative web environment Digital repository

Best practices for electrochemical characterization of supercapacitors

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Journal of Energy Chemistry 2023年第5期80卷 265-283,I0007页

作者： João Pedro Aguiar dos santos Fernando Cesar Rufino Joǎo IYutaka Ota Rodolfo CFernandes Rafael Vicentini Cesar JBPagan leonardo Morais Da Silva Hudson Zanin Brazilian Renewable Energies Center for Innovation on New EnergiesSchool of Electrical and Computer EngineeringUniversity of CampinasSP 13083-852Brazil School of Electrical and Computer Engineering University of CampinasSP 13083-852Brazil Department of Chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha e Mucuri's ValleyRodovia MGT 367km 5835000Alto da Jacuba39100-000 DiamantinaMGBrazil

We discuss here essential aspects of the experimental supercapacitors characterization by a series of well-known electrochemical *** are motivated by a considerable number of publications that misreport procedures and *** often conceal or neglect essential information about the electrochemical analytical apparatus used and its *** lack of such information may lead researchers,especially inexperienced ones,to misunderstand the procedures and ***,the misled electrochemical equipment configuration favors misinterpretation of data and low reproducibility *** paper aims to highlight these issues and clarify *** explain fundamental concepts of some electrochemical analytical methods,such as cyclic voltammetry,galvanostatic charge-discharge,single potential step chronoamperometry,and electrochemical impedance spectroscopy,focusing on the supercapacitor *** configurations of electrical parameters are presented and discussed to highlight the effects of incorrect setup and uncover misleading *** discuss how the electrochemical setup and data analyses matter in reliable data results for the supercapacitor.

关键词： Supercapacitor Electrochemical instrumentation Electrochemical methods Electrochemistry

Distinguishing the Regional Atmospheric Controls on Precipitation Isotopic Variability in the Central-Southeast Portion of Brazil

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Advances in Atmospheric Sciences 2022年第10期39卷 1693-1708,I0018-I0020页

作者： Vinícius dos santos Peter MARSHALL FLEMING Luís HENRIQUE MANCINI Stela DALVA santos COTA Graziele Beatriz de lima Rafaela RODRIGUES GOMES Roberto Eduardo KIRCHHEIM Ricardo SANCHÉZ-MURILLO Didier GASTMANS São Paulo State University(UNESP) Environmental Studies Center.Av.24ABased1515-Bela Vista13.506-900Rio Claro(SP)Brazil Center for the Development of the Nuclear Technology(CDTN-CNEN) Av.Presidente Antônio Carlos6.627Campus da UFMG-Pampulha31270-90Belo Horizonte(MG)Brazil Universidade de Brasília-UnB Instituto de GeociênciasLaboratório de Isótopos Estáveis.Campus"Darcy Ribeiro"Asa Norte70.910-900Brasília(DF)Brasil Hydrology and Territorial Management Directory(DHT) The Geological Survey of Brazil(CPRM-SGB)São Paulo(SP)Brazil University of Texas at Arlington Earth and Environmental Sciences Department500 Yates StreetArlingtonTexas76019USA Stable Isotopes Research Group and Water Resources Management Laboratory Universidad NacionalHerediaCosta Rica

Precipitation isotope ratios(O and H)record the history of water phase transitions and fractionation processes during moisture transport and rainfall ***,we evaluated the isotopic composition of precipitation over the central-southeastern region of Brazil at different *** isotopic compositions were associated with classical effects(rainfall amount,seasonality,and continentality),demonstrating the importance of vapor recirculation processes and different regional atmospheric systems(South American Convergence Zone-SACZ and Cold Fronts-CF).While moisture recycling and regional atmospheric processes may also be observed on a daily timescale,classical effects such as the amount effect were not strongly correlated(δ^(18)O-precipitation rate r≤-0.37).Daily variability revealed specific climatic features,such asδ^(18)O depleted values(~-6‰to-8‰)during the wet season were associated with strong convective activity and large moisture *** isotopic analysis revealed the role of different moisture sources and transport *** ratios combined with d-excess explain how atmospheric recirculation processes interact with convective activity during rainfall formation *** findings provide a new understanding of rainfall sampling timescales and highlight the importance of water isotopes to decipher key hydrometeorological processes in a complex spatial and temporal context in central-southeastern Brazil.

关键词： precipitation stable water isotopes d-excess moisture source and transport southern Atlantic Ocean and Amazon