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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

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Urbanization drives adaptive evolution in a Neotropical bird

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current Zoology 2023年第5期69卷 607-619页

作者： rilquer Mascarenhas Pedro Milet Meirelles Henrique Batalha-filho National Institute of Science and Technology in Interdisciplinary and Transdisciplinary Studies in Ecology and Evolution(INcT IN-TrEE) Instituto de BiologiaUniversidade Federal da Bahia40170-115 SalvadorBahiaBrazil

Urbanization has dramatic impacts on natural habitats and such changes may potentially drive local adaptation of urban *** change has been specifically shown to facilitate the fast adaptation of birds to changing environments,but few studies have investigated the genetic mechanisms of this *** investigations could provide insights into questions about both evolutionary theory and management of urban *** this study,we investigated whether local adaptation has occurred in urban populations of a Neotropical bird species,coereba flaveola,specifically addressing whether observed behavioral adaptations are correlated to genetic signatures of natural *** answer this question,we sampled 24 individuals in urban and rural environments,and searched for selected loci through a genome-scan approach based on rADseq genomic data,generated and assembled using a reference genome for the *** recovered 46 loci as putative selection outliers,and 30 of them were identified as associated with biological processes possibly related to urban adaptation,such as the regulation of energetic metabolism,regulation of genetic expression,and changes in the immunological ***,genes involved in the development of the nervous system showed signatures of selection,suggesting a link between behavioral and genetic *** findings,in conjunction with similar results in previous studies,support the idea that cities provide a similar selective pressure on urban populations and that behavioral plasticity may be enhanced through genetic changes in urban populations.

关键词： behavioral adaptation phenotypic plasticity selection selective sweep South America

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Hybridization despite elaborate courtship behavior and female choice in Neotropical tree frogs

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Integrative Zoology 2023年第2期18卷 208-224页

作者： renato c.NALI Kelly r.ZAMUDIO cynthia P.A.PrADO Programa de Pós-Graduação em Ecologia Evolução e BiodiversidadeInstituto de BiociênciasUniversidade Estadual PaulistaRio ClaroSão PauloBrazil Department of Ecology and Evolutionary Biology Cornell UniversityIthacaNew YorkUSA Department of Integrative Biology University of TexasAustinTexasUSA Departamento de Morfologia e Fisiologia Animal Faculdade de Ciências Agrárias e VeterináriasUniversidade Estadual Paulista“Júlio de Mesquita Filho”JaboticabalSão PauloBrazil

The mechanisms of hybridization can be elucidated by analyzing genotypes as well as phenotypes that could act as premating barriers,as the reproductive interactions among heterospeciﬁcs can alter the evolutionary history of *** frogs,hybrids typically occur among species that reproduce explosively(in dense aggregations)with few opportunities for mate selection but are rare in species with elaborate courtship behaviors that may prevent erroneous *** 21 microsatellite markers,we examined hybridization in the prolonged-breeding tree frogs Bokermannohyla ibitiguara and *** sampled within a contact zone in the Brazilian savanna(72 tadpoles;74 adults).We also compared acoustic and morphological *** conﬁrmed both parental species genetically;STrUcTUrE results conﬁrmed 14 hybrids,11 of which were second-generation according to NEWHYBrIDS,all with intermediate values of genetic dissimilarities compared to the *** and acoustic analyses revealed that hybrids showed variable but not necessarily intermediate ***,2 hybrids exhibited call types different from *** reproduction of *** involves territorial and aggressive males,elaborate courtships with acoustic and tactile stimuli,choosy females,and opportunistic *** study uncovers a rare case of viable hybridization among closely related frogs with such a combination of complex courtship behaviors and mate *** discuss the likely directionality and mechanisms behind this phenomenon,and highlight the importance of investigating hybridization even in species that show elaborate reproduction and female choice to advance our understanding of animal diversiﬁcation.

关键词： heterospeciﬁc mating hybrid zone Hylidae microsatellites prolonged-breeding

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Physical Properties in Drying of Food Products with combined Sublimation and Evaporation

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chinese Journal of chemical Engineering 2004年第6期12卷 814-817页

作者： Ingvald Strфmmen Odilio Alves-filho Trygve M.Eikevik Ingrid c.claussen Department of refrigeration and Air conditioning The Norwegian University of Science and Technology (NTNU) Trondheim NorwaySINTEF Energy Research Department of Refrigeration and Air Conditioning Trondheim NorwaySINTEF Energy Research Department of Refrigeration and Air Conditioning Trondheim NorwayDepartment of Refrigeration and Air Conditioning The Norwegian University of Science and Technology (NTNU) Trondheim Norway

Drying is an important unit operation in processing of biological resources. The drying process may influence the product properties and quality, which may shrink, break or undergo rheological, physical and biochemical changes. The important parameters responsible for such changes are drying conditions, type of drying technology and residence drying time. Thermal conductivity, thermal-mass diffusivity, enthalpy, porosity and density are the main material property and heat-mass transfer parameters, which are essential for understanding the changes in product quality and for designing and dimensioning the drying processes. In this paper physical properties of food products undergoing a combined sublimation and evaporation were studied. Pieces of vegetables and potatoes were dried in a heat pump fluidized bed dryer at combined modes with temperatures below the freezing point in the beginning and a final drying step at temperatures above the freezing point. Samples of products were tested at different moisture contents with respect to physical properties. Physical properties of leek and potato samples were measured and mass diffusivities were determined from drying kinetic data. Based on bulk density and rehydration measurements it was clearly observed that drying temperature and modes influenced the final product physical properties. The potato cube run dried with initial atmospheric freeze-drying step had rehydration ability 430%above a run dried only above the freezing point. The average effective mass diffusivity for 5 mm slabs of leek was 0.5 x 10-11m2·s-1 for the sublimation stage and 2.2 x 10-11m2·s-1 for the evaporation stage.

关键词： physical properties dying food products sublimation evaporation

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Bioskin: A New Biomaterial for Therapeutical and Biotechnological Purposes

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复旦学报（自然科学版） 2005年第5期44卷 796-797页

作者： Xavier-filho L Laboratório de Produtos Naturais e Biotecnologia Instituto de Tecnologia e Pesquisa-ITP Universidade Tiradentes-UNIT Aracaju Sergipe Brazil

Bioskin is new material by Acetobacter xylinum, Saccharomyces cerevisae and Schyzosaccharomyces pombe in mixed culture on sucrose. The Material has been revealed as hypoaller- genic,antibiotic,antithermic and sedative. It is widely used for skin regeneration in therapy of burns as well as in odontological *** contains high amounts of D-glucosamine and N-acetyl-D-glucosamine. It does not produce ash after heating at 600 ℃ and its combustion heat is similar to that of several current woods, such as pine oak or maple Bioskin has been used to immobilize algal cells, fungal spores and Bacteria in order to study some metabolic events. In addition, immobilization, of several enzymes has been performed using bioskin as inert *** was immobilized at pH 7.0 by ionic adsorption (aminosugars provide a net positive charge neutral pH values) whereas several glycoproteins can be immobilized on bioskin by an affinity mechanism.

关键词：生物素生物材料微生物酵母生物聚合体

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High Accurate Howland current Source: Output constraints Analysis

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circuits and Systems 2013年第7期4卷 451-458页

作者： Pedro Bertemes-filho Alexandre Felipe Volney c. Vincence Department of Electrical Engineering State University of Santa Catarina (UDESC) Joinville Brazil

Howland circuits have been widely used as powerful source for exciting tissue over a wide frequency range. When a Howland source is designed, the components are chosen so that the designed source has the desired characteristics. However, the operational amplifier limitations and resistor tolerances cause undesired behaviors. This work proposes to take into account the influence of the random distribution of the resistors in the modified Howland circuit over the frequency range of 10 Hz to 10 MHz. Both output current and impedance of the circuit are deduced either considering or the operational amplifiers parameters. The probability density function due to small changes in the resistors of the circuit was calculated by using the analytical modeling. results showed that both output current and impedance are very sensitive to the resistors variations. In order to get higher output impedances, high operational amplifier gains are required. The operational amplifier open-loop gain increases as increasing the sensitivity of the output impedance. The analysis done in this work can be used as a powerful co-adjuvant tool when projecting this type of circuit in Spice simulators. This might improve the implementations of practical current sources used in electrical bioimpedance.

关键词： Howland current Source Electrical Bioimpedance Probability Density Function resistors Mismatching

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Yet Another Intelligent code-Generating System： A Flexible and Low-cost Solution

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Journal of computer Science & Technology 2018年第5期33卷 940-965页

作者： Joao Fabricio filho Luis Gustavo Araujo rodriguez Anderson Faustino da Silva Department of Informatics State University of Maringd Maringd-PR 87020-900 Brazil Federal University of Technology -- Parand Campo Mourao-PR 87301-899 Brazil

Modern compilers apply various code transformation algorithms to improve the quality of the target code. However, a complex problem is to determine which transformation algorithms must be utilized. This is difficult because of three reasons： a number of transformation algorithms, various combination possibilities, and several configuration possibil- ities. Over the last few years, various intelligent systems were presented in the literature. The goal of these systems is to search for transformation algorithms and thus apply them to a certain program. This paper proposes a flexible, low-cost and intelligent system capable of identifying transformation algorithms for an input program, considering the program＇s specific features. This system is flexible for parameterization selection and has a low-computational cost. In addition, it has the capability to maximize the exploration of available computational resources. The system was implemented under the Low Level Virtual Machine infrastructure and the results indicate that it is capable of exceeding, up to 21.36%, performance reached by other systems. In addition, it achieved an average improvement of up to 17.72% over the most aggressive compiler optimization level of the Low Level Virtual Machine infrastructure.

关键词： compiler code transformation iterative compilation knowledge representation machine learning

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Dendrochronology and climatic signals in the wood of Nectandra oppositifolia from a dense rain forest in southern Brazil

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Journal of Forestry research 2019年第2期30卷 545-553页

作者： Daniela Granato-Souza Eduardo Adenesky-filho Karin Esemann-Quadros Postgraduate Program in Forestry Regional University of Blumenau-FURB Department of Biological Sciences University of Joinville Region-UNIVILLE

Nectandra is one of the most representative genera of Lauraceae in the subtropical Atlantic Forest of Brazil. The objective of this work was to study the dendrochronological potential of Nectandra oppositifolia Nees and Mart. from two sites in Santa catarina State in southern Brazil. A tree-ring chronology of 34 trees was developed. The time span ranged from 1843 to 2013. The oldest and youngest trees were 171 and 47 years-old and the average length of the series was 103 years. Average diameter and annual increment were 20.64 cm and0.74 mm a-1; diameter and age were unrelated. The species has good dendrochronological potential with an intercorrelation of 0.61 between sites, indicating the existence of a synchronous pattern in the development of the trees. The climate response of the species could be seen by negative tree growth effects for previous hot and current rainy growth seasons.

关键词： climate response Dendroclimatology Atlantic forest Growth rings Lauraceae

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Mechanical Properties of Polypropylene composites reinforced with Macadamia Nutshell Fibers

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Journal of renewable Materials 2019年第10期7卷 1047-1053页

作者： Joyce de P.cipriano N.c.Zanini I.r.Dantas D.r.Mulinari Faculdade de Tecnologia/FAT/UErJ Rodovia Presidente Dutra km 298 Polo IndustrialResende27537-000Brazil Universidade Federal Fluminense Avenida dos Trabalhadores420Vila Santa CecíliaVolta Redonda27255-125Brazil

The use of natural fibers as an additive in polymeric matrices has attracted interest of the automotive industries,for its low cost,mechanical properties,biodegradability and ***,the hydrophilic nature of the fiber makes polymer compatibility *** surface treatments can be used to enhance the fiber/matrix *** the present work,polypropylene(PP)composites reinforced with fibers from macadamia nutshell were obtained and *** nutshell fibers were treated by an alkaline treatment with sodium hydroxide(NaOH 4%)to improve adhesion between fibers and *** were characterized by techniques of Scanning Electron Microscopy(SEM)and X-ray Diffraction(XrD).The PP was mixed with the macadamia fibers(treated and untreated),in proportions of 5 and 10%(wt/wt)using a thermokinetic *** tensile,flexural and impact specimens(Pure PP and composites)were prepared by an injection molding process and tested for evaluation of mechanical *** results showed that the insertion of treated fibers in the PP matrix increased the stiffness of the ***,the composites reinforced with untreated fibers presented higher impact energy absorption when compared to composites reinforced with treated fibers.

关键词： Macadamia nutshell polypropylene alkaline treatment mechanical properties

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Motor speed estimation and failure detection of a small UAV using density of maxima

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Frontiers of Information Technology & Electronic Engineering 2021年第7期22卷 1002-1009页

作者： Jefferson S.SOUZA Moises c.BEZErrIL Mateus A.SILVA Frank c.VErAS Abel LIMA-filho Jorge Gabriel rAMOS Alisson V.BrITO Laboratory of System Engineering and robotics Federal University of ParaibaJoao PessoaBrazil Department of Information Systems Federal University of PiauiPicosBrazil Department of Mechanical Engineering Federal University of ParaibaJoao PessoaBrazil Department of Physics Federal University of ParaibaJoao PessoaBrazil

This work presents the application of the technique named signal analysis based on chaos using density of maxima to analyze brushless direct current *** uses a correlation coefficient estimated from the density of maxima of the current *** study demonstrates in experiments the speed estimation of a brushless motor on a testbench and failure detection in a small flying *** experimental results demonstrate that it is possible to estimate the speed in 97.8%of the cases and to detect failure in 82.75%of the analyzed cases.

关键词： Unmanned aerial vehicle(UAV) Speed identification Failure detection chaos

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