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Journal of Civil Engineering and Architecture 2015年第9期9卷 1017-1024页

作者： Eliana Cristina Barreto Monteiro victor Correia de oliveira pereira department of Civil Engineering University of Pernambuco Recife 50720-001 Brazil department of Civil Engineering Catholic University of Pernambuco Recife 50050 900 Brazil

To examine the protection against reinforcement corrosion due to the combined action of CO2 and chlorides, experimental results of the evaluation of a study with three types of cement are presented. The study was performed observing the behavior of reinforcements which were put in samples submitted to accelerated carbonatation tests and accelerated tests under the effect of chlorides. For the evaluation, intensity corrosion measurements were used using the Pr （polarization resistance） technique, employing these measures as a deterioration indicator. Three types of cement available in the national market were used. The obtained results enabled the classification of the used cements, comparing their profile behaviors in the conditions of the proposed tests.

关键词： Carbonation chlorides corrosion reinforced concrete polarization resistance.

Assessment of the Presence of Chlorides in Mortar through the Silver Nitrate Colorimetric Spraying Method

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Journal of Civil Engineering and Architecture 2015年第6期9卷 677-683页

作者： victor Correia de oliveira pereira Eliana Cristina Barreto Monteiro department of Civil Engineering University of Pernambuco Recife 50720-001 Brazil department of Civil Engineering Catholic University of Pernambuco Recife 50720-001 Brazil

This study aims to evaluate the presence of free chlorides by the silver nitrate colorimetric spraying method in mortars made with Portland cement CP II Z-32. In order to make an assessment beyond the qualitative analysis, a calculation of the contaminated areas by free chlorides was performed by measuring the regions using a computer image analysis software （IMAGEJ）. The experimental part of the research involved samples of 5 cm x 10 cm of mortar and 0.1 M solution of silver nitrate in distilled water. The mortar samples were made with cement CP II Z-32 with the following concentrations of chloride incorporated into the mixing water： 0%0, 0.4%, 0.6%, 0.8%, 1.0% and 2.0%, in relation to the mass of cement, totaling 108 samples. The average of percentage results from the contaminated area of the series of samples was respectively 0%, 14.9694%, 19.7444%, 46.0239%, 62.3311% and 96.0083% in relation to the total area, concluding that the method of silver nitrate spraying is applicable and that the white color indicates the presence of chloride ions and other possible aggressive salts to the structure or the concrete.

关键词： Silver nitrate chloride ions corrosion colorimetric method.

Behavior of wood basic density according to environmental variables

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Journal of Forestry Research 2022年第2期33卷 497-505页

作者： Gabriel Marcos Vieira oliveira JoséMárcio de Mello Carlos Rogério de Mello JoséRoberto Soares Scolforo Eder pereira Miguel Thiago Campos Monteiro Brazil Institute of Agricultural and Forestry defense of Espírito Santo(IDAF) Av.Lourival Lugon Moulinnº300CentroJerônimo MonteiroES CEP:29.550-000Brazil department of Forestry Sciences Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Engineering department Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Forestry Engineering department Faculdade de TecnologiaUniversity of Brasilia-UnBCampus Universitário Darcy RibeiroCaixa Postal 4357Asa Norte-BrasíliaDF CEP:70910-900Brazil department of Forestry Engineering and Technology Universidade Federal do Paraná-UFPRAv.Pref.Lothário Meissner632Jardim BotânicoCuritibaPR CEP:80.210-170Brazil

The relationships between climate conditions and wood density in tropical forests are still poorly *** quantify spatial dependence of wood density in the state of Minas Gerais(MG,Brazil),map spatial distribution of density,and correlate density with climate variables,we extracted data from the Forest Inventory of Minas Gerais for 1988 trees scaled throughout the territory and measured wood density of discs removed from the *** variables were extracted from the database of the Ecological-Economic Zoning of Minas *** spatial analysis,tree densities were measured at 44 georeferenced sampling *** data were subjected to exploratory analysis,variography,cross-validation,model selection,and ordinary *** relationships between wood density and environmental variables were calculated using dispersion matrices,linear correlation,and *** density proved to be highly spatially dependent,reaching a correlation of 96%,and was highly continuous over a distance of 228 *** distribution of wood density followed a continuous gradient of 514-659 kg m^(−3),enabling corre-lation with environment *** was correlated with mean annual precipitation(−0.57),temperature(0.63),and evapotranspiration(0.83).Geostatistical methods proved useful in predicting wood density in native tropical forests with different climate *** results confirmed the sensitivity of wood density to climate change,which could affect future carbon stock in forests.

关键词： Biomass Climate variables Geostatistics Hardwood Forest inventory Minas Gerais

Flight performance and wing morphology in the bat Carollia perspicillata:biophysical models and energetics

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Integrative Zoology 2023年第5期18卷 876-890页

作者： Lucas de oliveira CARNEIRO Breno MELLADO Marcelo Rodrigues NOGUEIRA Ariovaldo pereira da CRUZ-NETO Leandro Rabello MONTEIRO Laboratório de Ciências Ambientais Centro de Biociências e BiotecnologiaUniversidade Estadual do Norte FluminenseCampos dos GoytacazesRio de JaneiroBrasil departamento de Biodiversidade Universidade Estadual PaulistaRio ClaroSão PauloBrasil

Studies on functional performance are important to understand the processes responsible for the evolution of *** trait variation within species influences the energetic cost of locomotion and impacts life history traits,with ecological and evolutionary *** study examined wing morphology correlates of flight performance measured by energetic expenditure in the Seba’s short-tailed bat,Carollia *** the flight experiments,nature caught bats(59 females,57 males)were allowed to fly for 3 min in a *** each flight,thermographic images were taken to measure body temperature,and biophysical models were used to calculate sensible heat loss as a measure of energetic *** morphological traits were measured for each individual and associated with heat loss and power required to fly on performance *** morphological traits explained 7-10%of flight energetic cost,and morphologies with the best performance would save the energy equivalent to 9-30%of total daily *** optimal performance areas within the *** morphospace were consistent with predicted selection trends from the literature.A trade-off between demands for flight speed and maneuverability was *** loading and camber presented sexual *** morphological differences are likely associated with more economical but less maneuverable flight in females,leading them to fly more often in open areas along the forest *** findings demonstrate how small scale changes in wing morphology can affect life history strategies and fitness.

关键词： aerodynamics Chiroptera infrared thermography performance surfaces Phyllostomidae wing morphometrics

Effect of applying a calcined kaolin-based particle film on the photosynthetic capacity and growth of young eucalyptus plants

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Journal of Forestry Research 2021年第6期32卷 2473-2484页

作者： Diego pereira Santos Mauriana da Rocha Sobrinho Maria de Fatima de Castro oliveira Niedja Bezerra Costa Tiago Massi Ferraz Fabricio de oliveira Reis Heder Braum Eliemar Campostrini Fabio Afonso Mazzei Moura de Assis Figueiredo Graduate Program in Agriculture and Environment State University of MaranhaoPraca Goncalves Diass/nCentroBalsasMA 65800-000Brazil Graduate Program in Agroecology State University of MaranhaoAv.Lourenco Vieira da Silva1000Jardim Sao CristovaoSao LuisMA 65055-310Brazil Graduate Program in Agronomy Campus SamambaiaEscola de AgronomiaFederal University of GoiasAv.Esperanca s/nGoianiaGO 74690-900Brazil State University of Maranhao Av.Lourenco Vieira da Silva1000Jardim Sao CristovaoSao LuisMA 65055-310Brazil Northern Rio de Janeiro State University Av.Alberto Lamego2000Campos dos GoytacazesRJ 28013-602Brazil

In scenarios of climatic change when increased global temperatures can be expected,it is essential to search for technologies that favor sapling survival and growth after planting and increase yield in the ***-based particle films(KBPF)have been applied as barriers against the deleterious effects of high levels of solar *** objective of the present study was to assess the effects of applying purified calcined kaolin-based particle film to young eucalyptus *** treatments were carried out:0%(just water),3%,5%,7%,and 10%calcined kaolin applied to the adaxial part of the leaves.A complete randomized block design was used with five treatments and ten *** plants were assessed for height,diameter at ground level,gas exchanges(net photosynthetic CO_(2) assimilation,stomatal conductance and transpiration),instantaneous(WUE)and intrinsic water use efficiency(IWUE),chlorophyll a fluorescence(maximum quantum yield of photosystem II(PSII)(Fv/Fm),concentration of active reaction centers in relation to the quantity of photons absorbed(RC/ABS)and the maximum ratio of quantum yields of photochemical and concurrent non-photochemical processes in PSII(Fv/F0),SPAD reading and leaf *** 3%KBPF concentration showed the best responses in biometric assessments 80 days after planting(DAP)and were corroborated by the responses of the leaf,stem and shoot dry matter production as a *** leaf ontogeny assessments showed positive responses following KBPF application when considering leaf development,with 7%KBPF concentration resulting in the highest mean *** mean specific leaf mass had negative response to high KBPF *** 60 DAP,the gas exchange variables during both assessment periods declined with an increase in KBPF *** differences as a result of KBPF applications were found only at the start of the assessments(34 DAP)for both WUE and for ***‘greenness’(SPAD reading)at 47 days showed a quadratic

关键词： Ecophysiology Photoprotection Yield Silviculture

Choosing the best endoscopic approach for post-bariatric surgical leaks and fistulas:Basic principles and recommendations

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World Journal of Gastroenterology 2023年第7期29卷 1173-1193页

作者： victor Lira de oliveira Alexandre Moraes Bestetti Roberto Paolo Trasolini Eduardo Guimaraes Hourneaux de Moura Diogo Turiani Hourneaux de Moura Serviço de Endoscopia Gastrointestinal Departamento de GastroenterologiaHospital das Clínicas da Faculdade de Medicina da Universidade de São PauloSão Paulo 05403010Brazil Division of Gastroenterology Hepatology and EndoscopyHarvard Medical SchoolBrigham and Women's HospitalBostonMA 021115United States

Post-surgical leaks and fistulas are the most feared complication of bariatric *** have become more common in clinical practice given the increasing number of these procedures and can be very difficult to *** two related conditions must be distinguished and characterized to guide the appropriate *** is defined as a transmural defect with communication between the intra and extraluminal compartments,while fistula is defined as an abnormal communication between two epithelialized ***,surgical treatment was the preferred approach for leaks and fistulas and was associated with high morbidity with significant mortality ***,with the development of novel devices and techniques,endoscopic therapy plays an increasingly essential role in managing these *** diagnosis and endoscopic therapy initiation after clinical stabilization are crucial to success since clinical success rates are higher for acute leaks and fistulas when compared to late and chronic leaks and *** endoscopic techniques are available with different mechanisms of action,including direct closure,covering/diverting or *** treatment should be individualized by considering the characteristics of both the patient and the *** there is a lack of high-quality studies to provide standardized treatment algorithms,this narrative review aims to provide a summary of the current scientific evidence and,based on this data and our extensive experience,make recommendations to help choose the best endoscopic approach for the management of post-bariatric surgical leaks and fistulas.

关键词： Endoscopy Surgery Bariatric Gastrointestinal Fistulas Leaks

Metamorphic disturbances of magnetite chemistry and the Sm-Nd isotopic system of reworked Archean iron formations from NE Brazil

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Geoscience Frontiers 2022年第5期13卷 227-241页

作者： Joice Dias de Moraes Pedro Cordeiro Eduardo Abrahão Filho Juliana Rezende oliveira Carlos victor Rios da Silva Filho Instituto de Geociências Universidade de Brasília(UnB)70910-900 BrasíliaDFBrazil department of Mining Engineering Pontifical Catholic University of Chile7820436 SantiagoChile

Iron formations are valuable archives of sedimentary conditions and post-depositional ***,geochemical proxies commonly used to determine genetic characteristics can be variably modified during metamorphism and deformation,hampering their use as records of regional geological *** work focuses on strongly reworked magnetite-quartz-rich rocks from the São Josédo Campestre Massif,one of the oldest fragments of preserved crust in South *** genetic classification of these magnetite-quartz-rich rocks is not straightforward because primary assemblages and textures were variably modified by granulite facies metamorphism during a regional Paleoproterozoic migmatization *** address genetic ambiguities,we analyzed their magnetite and pyroxene chemistry,wholerock geochemistry,and Sm-Nd *** chemistry indicates that pyroxene-poor iron formations(Type B)are low in trace elements such as Ti,Al,V,and Mn,suggesting a chemical similarity to iron formations *** contrast,magnetites from pyroxene-enriched Type A iron formations are rich in trace elements and more akin to magnetite crystallized from higher temperature systems,such as skarn and ***^(147)Sm/^(144)Nd of these rocks show substantial variation even at the outcrop scale,indicating a locally-controlled,highly heterogeneous mixture of Archean,Paleoproterozoic,and Neoproterozoic ***,our geochemical tools point out to heterogenous signatures of these magnetitequartz rocks and proxies compatible with both low and high-temperature conditions and age of deposition spanning sources from the Archean to the *** interpret that the studied São Josédo Campestre magnetite-quartz rocks represent Archean iron formations with original magnetite chemistry and isotopic signatures variably modified by metamorphism and by at least one deformation-related hydrothermal *** results contrast with similar examples from China and Greenland where iron formation

关键词： Metamorphic disturbances of magnetite chemistry and the Sm-Nd isotopic system of reworked Archean iron formations from NE Brazil

Soil texture prediction through stratification of a regional soil spectral library

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Pedosphere 2022年第2期32卷 294-306页

作者： José Janderson Ferreira COSTA élvio GIASSON Elisangela Benedet DA SILVA Tales TIECHER Antonny Francisco Sampaio de SENA Ryshardson Geovane pereira de oliveira E SILVA department of Soil Science Faculty of AgronomyUniversity of Rio Grande do SulBento Gonçalves Avenue 7712Porto Alegre 91540-000Brazil Agricultural Research and Rural Extension Corporation of Santa Catarina Rodovia Admar Gonzaga 1347FlorianópolisSanta Catarina 88034-901Brazil

Knowing the spatial distribution of soil texture,which is a physical property,is essential to support agricultural and environmental decision *** texture can be estimated using visible,near infrared,and shortwave infrared(Vis-NIR-SWIR)***,the performance of spectroscopic models is variable because of soil ***,few studies address the effects of soil sample variability on the performance of the models,especially for larger spectral libraries that include soils that are more ***,the objectives of this study were to:i)apply Vis-based color parameters on the stratification of a regional soil spectral library;ii)evaluate the performance of the predictive models generated from the spectral library stratification;iii)compare the performance of stratified models(SMs)and the model without stratification(WSM),and iv)explain possible changes in prediction accuracy based on the ***,a regional soil spectral library with 1535 samples from the State of Santa Catarina,Brazil was *** reflectance data were obtained by Vis-NIR-SWIR spectroscopy in the laboratory using a spectroradiometer covering the 350–2500 nm spectral ***,silt,and clay fractions were determined using the pipette ***-two components of color parameters were derived from the Vis spectrum using the colorimetric models.A cubist regression algorithm was used to assess the accuracy of the applicability of the initial models(SMs and WSM)and of the validation between the *** order derivatives(FODs)at 0.5,1.5,and 2 intervals were used to explain possible changes in the performance of the *** SMs with higher contents of clay and iron oxides obtained the highest accuracy,and the most important spectral bands were identified,mainly in the 480–550 and 850–900 nm ranges and the 1400,1900,and 2200 nm ***,stratification of soil spectral libraries is a good strategy to improve regional assessments of soil resou

关键词： color parameters cubist regression fractional order derivatives soil spectroscopy spectroscopic model stratified model Vis-NIR-SWIR

Rat Cerebrospinal Fluid Treatment Method through Cisterna Cerebellomedullaris Injection

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Neuroscience Bulletin 2018年第5期34卷 827-832页

作者： Thaina Garbino dos Santos Mery Stefani Leivas pereira Diogo Losch oliveira Laboratory of Cellular Neurochemistry Departamento de Bioquimica Instituto de Ciencias Basicas da Saude Universidade Federal do Rio Grande do Sul Porto Alegre RS 90035-003 Brazil

Drugs that lack the ability to cross the blood- brain barrier （BBB） need to be placed directly into the central nervous system. Our laboratory studies the involve- ment of the glutamatergic system in the aggressiveness of glioma, and some ligands of glutamate receptors cannot permeate the BBB. Here, glioma-implanted rats were treated by a technique that delivers ligands directly into the cerebrospinal fluid by puncture into the cisterna cerebel- lomedullaris. Rats were anesthetized and fixed in a rodent stereotactic device. The head was gently tilted downwards at an angle that allowed exposure of the cisterna. Injection into the cisterna was done freehand using a gingival needle coupled to a microsyringe. The efficiency of intracisternal injection was demonstrated using a methylene blue solu- tion. This type of injection is adaptable for any rodent model using small volumes of a variety of other drugs, and is an interesting method for neuroscience studies.

关键词： Neurobiology Neuroscience Drug administration Intracisternal injection Cisterna magna Cerebrospinal fluid treatment Central nervous system Surgical technique Rodent

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