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Recovery of rare-earth metals from aqueous solutions by bio/adsorption using non-conventional materials:a review with recent studies and promising approaches in column applications

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Journal of Rare Earths 2020年第4期38卷 339-355页

作者： Talles Barcelos da costa Meuris Gurgel Carlos da silva Melissa Gurgel Adeodato Vieira University of Campinas School of Chemical EngineeringAlbert Einstein Avenue50013083e852 CampinasBrazil

The recovery of rare-earth metals(REMs)is of great economic and environmental interest,because of their high market prices and various industrial ***,with the increasing demand for high-purity rare-earth compounds,the separation and purification of these elements have gained considerable *** bio/adsorption process has been considered an alternative to recover these elements,by its simplicity,low cost and efficiency for recovery of REMs at low *** review article presents the recent progress regarding REM bio/adsorption published literature in batch system by different non-conventional bio/adsorbents,as well as a critical analysis of the technological challenges to be faced and future *** this purpose,the best application model(isotherm,kinetics),thermodynamic quantities and selection of eluents for desorption studies are also ***,in this review,the application of different bio/adsorbent materials were reviewed extensively in terms of the removal and recovery of REMs in continuous fixed-bed adsorption and regeneration ***,future aspects in bio/adsorption research and prospects for commercial applications were discussed.

关键词： Rare-earth metals Bio/adsorbents Adsorption kinetics Isotherm Batch desorption Continuous fixed-bed adsorption

Performance of masonry enclosure walls:lessons learned from recent earthquakes

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Earthquake Engineering and Engineering Vibration 2012年第1期11卷 23-34页

作者： Romeu silva Vicente Hugo Rodrigues Humberto Varum Aníbal costa Jos António Raimundo Mendes da silva University of Aveiro Civil Engineering Department Campus Universitario de SantiagoAveiroPT3810-193Portugal University of Coimbra Civil Engineering Pinhal de MarrocosPolo ⅡCoimbraPT3030Portugal

This paper discusses the issue of performance requirements and construction criteria for masonry enclosure and infill walls. Vertical building enclosures in European countries are very often constituted by non-load-bearing masonry walls, using horizontally perforated clay bricks. These walls are generally supported and confined by a reinforced concrete frame structure of columns and beams/slabs. Since these walls are commonly considered to be nonstructural elements and their influence on the structural response is ignored, their consideration in the design of structures as well as their connection to the adjacent structural elements is frequently negligent or insufficiently detailed. As a consequence, nonstructural elements, as for wall enclosures, are relatively sensitive to drift and acceleration demands when buildings are subjected to seismic actions. Many international standards and technical documents stress the need for design acceptability criteria for nonstructural elements, however they do not specifically indicate how to prevent collapse and severe cracking, and how to enhance the overall stability in the case of moderate to high seismic loading. Furthermore, a review of appropriate measures to improve enclosure wall performance and both in-plane and out-of-plane integrity under seismic actions is addressed.

关键词： RC structures masonry enclosure walls infill walls in-plane out-of-plane cracking performanceimprovement

Compounds from Stevia rebaudiana Bertoni leaves: An overview of non-conventional extraction methods and challenges

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Food Bioscience 2022年第2期46卷 108-121页

作者： Dj´essica Tatiane Raspe Camila da silva Silvio Cl´audio da costa ograma de P´os-Graduaç˜ao em Ciˆencia de Alimentos Universidade Estadual de Maring´aAv.Colombo579087020-900Maring´aPRBrazil Departamento de Tecnologia Universidade Estadual de Maring´aAv.ˆAngelo Moreira da Fonseca180087506-370UmuaramaPRBrazil Departamento de Bioquímica Universidade Estadual de Maring´aAv.Colombo579087020-900Maring´aPRBrazil

To overcome the inconveniences related to its conventional obtainment of natural sweeteners and active compounds from Stevia rebaudiana Bertoni,methods involving application of technology,such as ultrasound assisted extraction,microwave assisted extraction,extraction under pressurized conditions by means of pressurized liquid extraction,subcritical water extraction and supercritical fluid extraction have been *** this review,these emerging techniques were analyzed and discussed,the process variables and operational strategies,their impacts on the extraction and their comparison against the conventional techniques were *** and the possibility of operational automation,the use of less energy and solvents,in addition to the reduced complexity of the subsequent purification steps,make up viable alternatives suitable for a possible industrial *** processes leverage the concept of green chemistry,but still suffer limitations related to acquisition and maintenance costs,in addition to the effects of the action of some of these technologies remaining unexplored.

关键词： Active compounds Natural sweeteners Steviol glycosides Technology application

The corpus cavernosum after treatment with dutasteride or finasteride： a histomorphometric study in a benign prostatic hyperplasia rodent model

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Asian Journal of Andrology 2018年第5期20卷 505-510页

作者： Marcello H A da silva Waldemar S costa Francisco J B Sampaio Diogo B De Souza Urogenital Research Unit Rio de Janeiro State University Rio de Janeiro RJ 20551-030 Brazil

Erectile dysfunction is a common side effect of finasteride and dutasteride treatments. The objective of this study was to investigate the structural changes in the penis using a benign prostatic hyperplasia （BPH） rodent model treated with dutasteride or finasteride. Sixty male rats were divided into the following groups： C, untreated control rats; C ＋ D, control rats receiving dutasteride; C ＋ F, control rats receiving finasteride; H, untreated spontaneously hypertensive rats （SHRs）; H ＋ D, SHRs treated with dutasteride; and H ＋ F, SHRs treated with finasteride. Treatments were performed for 40 days, and penises were collected immediately thereafter. The organs were analyzed using histomorphometric methods to determine the cross-sectional penile area, as well as the surface density （Sv） of smooth muscle fibers, connective tissue, elastic system fibers, and sinusoidal spaces of the corpus cavernosum. The results were compared using a one-way ANOVA with Bonferroni＇s posttest. Groups C ＋ D and C ＋ F had a significantly smaller penile cross-sectional area, but more elastic system fiber Sv compared to Group C. Group C ＋ D showed less smooth muscle Sv, and Group H showed more connective tissue but a smaller sinusoidal space Sv in the corpus cavernosum compared to Group C. Groups H ＋ D and H ＋ F had less smooth muscle Sv than Group H. Group H ＋ D also had more connective tissue and elastic system fiber Sv than Group H. Both dutasteride and finasteride promoted penile modifications in the control rat penis, although this affect was ~reater in Group H animals. In this rodent model, dutasteride was the drug that most affected the corpus cavernosum.

关键词： animal models benign prostatic hyperplasia dutasteride erectile dysfunction finasteride penis

Comparative stability analyses of traditional and selective room-and-pillar mining techniques for sub-horizontal tungsten veins

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 1-8页

作者： Vidal Felix Navarro Torres Carlos Dinis da Gama Matilde costa e silva Paula Falcao Neves Qiang Xie Mining and Geo-resources Engineering Department of IST Technical University of Lisbon 1049-001 Portugal Faculty of Civil Engineering Chongqing University Chongqing 400045 China

The stability and productivity concerning a modification on the traditional room and pillar for a new selective technique at the Portuguese Panasqueira Mine have been *** traditional room-and-pillar stoping uses 5.0-m wide rooms with 3.0 m×3.0 m pillars,while the selective room-and-pillar mining technique consists in stoping with rooms of 4.0 m wide and pillars of 4 m×4 m with a subsequent selective cutting of the quartz veins at the mid pillar of approximately 0.5 m high,to obtain a pillar section with an area of 3.0 m×3.0 *** stability and productivity analyses indicate that the selective technique obtains smaller average pillar safety factor,more rock mass displacement,more extraction and selectivity ratios,and ore grade improvement,compared with the traditional *** results show that the selective technique is also more *** proposed selective room-and-pillar mining technique is applicable to any sub-horizontal narrow quartz veins with wolfram,gold,*** as the famous La Rinconada gold mine in the Peruvian Andes.

关键词： mines and mining tungsten deposits productivity stability stoping

Sociodemographic,biological,and psychosocial correlates of light-and moderate-to-vigorous-intensity physical activity during school time,recesses,and physical education classes

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Journal of Sport and Health Science 2019年第2期8卷 177-182页

作者： Bruno G.G.da costa Kelly S.da silva Jaqueline A.da silva Giseli Minatto Luiz R.A.de Lima Edio L.Petroski Research Centre in Physical Activity and Health Federal University of Santa Catarina Department of Physical Education Federal University of Santa Catarina Research Centre in Kineanthropometry and Human Development Federal University of Santa Catarina

Background: Identifying factors associated with physical activity(PA) is useful in planning interventions and policies. The aim of this study was to identify sociodemographic, biological, and psychosocial factors associated with PA performed in school ***: data collected for the present study included gender, age, socioeconomic status, body fat percentage, aerobic fitness, self-efficacy, attitudes,peer and parental support, and perception of school environment. Dependent variables were light-intensity PA(LPA) and moderate-to-vigorousintensity PA(MVPA) performed during school time, recesses, and physical education(PE) classes. Multiple regression analyses were ***: Participating adolescents(n = 567, 53% female, 12.9 ± 5.3 years) spent 5% of school time in MVPA and 27% in LPA, 15% of recesses in MVPA and 44% in LPA, and 16% of PE classes in MVPA and 41% in LPA. Boys engaged in more MVPA in all categories. Age was inversely related with MVPA and LPA in all periods, whereas body fat percentage was inversely related with MVPA in school time and PE classes. Attitude was inversely related with MVPA in all periods and with LPA in recesses. Considering PA to be good and enjoyable was positively associated with MVPA in school ***: Adolescents spent little time in PA during school. Future interventions should implement enjoyable activities at school.

关键词： Accelerometer Adolescents Attitude Physical education Public health Self-efficacy

Reconstruction of the Neutron Flux in a Slab Reactor

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World Journal of Nuclear Science and Technology 2012年第4期2卷 181-186页

作者： Adilson costa da silva Aquilino Senra Martinez alessandro da Cruz Goncalves Nuclear Engineering Department Federal University of Rio de JaneiroRio de JaneiroBrazil

In this electronic article we use the one-dimensional multigroup neutron diffusion equation to reconstruct the neutron flux in a slab reactor from the nuclear parameters of the reactor, boundary and symmetry condition, initial flux and?keff. The diffusion equation was solved analytically for one single homogeneous fuel region and for two regions considering fuel and reflector. To validate the method proposed, the results obtained in this article were compared using reference methods found in the literature.

关键词： Neutron Diffusion Equation Neutron Flux Slab Reactor

Antiglycation and antioxidant activities of the crude extract and saponin fraction of Tribulus terrestris before and after microcapsule release

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Journal of Integrative Medicine 2022年第2期20卷 153-162页

作者： Célia Cristina Malaguti Figueiredo Amanda da costa Gomes Filipe Oliveira Granero Joao Luiz Bronzel Junior Luciana Pereira silva Valdecir Farias Ximenes Regildo Márcio Goncalves da silva Institute of Chemistry São Paulo State UniversityAraraquaraSão Paulo 14800-060Brazil Educational Foundation of the City of Assis AssisSão Paulo 19807-130Brazil Department of Chemistry School of SciencesSão Paulo State UniversityBauruSão Paulo 17033-360Brazil Department of Biotechnology School of SciencesHumanities and LanguagesSão Paulo State UniversityAssisSão Paulo 19806-900Brazil

Objective:The present study investigated antiglycation and antioxidant activities of crude dry extract and saponin fraction of Tribulus *** also developed a method of microencapsulation and evaluated antiglycation and antioxidant activities of crude dry extract and saponin fraction before and after microcapsule ***:Antiglycation activity was determined by relative electrophoretic mobility(REM),free amino groups and inhibition of advanced glycation end-product(AGE)*** activity was determined by 2,2-diphenyl-1-picrylhydrazyl(DPPH),ferric ion-reducing antioxidant power(FRAP),nitric oxide(NO)and thiobarbituric acid reactive species(TBARS)*** were prepared using maltodextrin as wall material and freeze-drying as encapsulation *** characterization of microcapsules was evaluated by scanning electron microscopy,and encapsulation efficiency and microcapsule release were determined by total saponins *** and antioxidant assays were performed using crude dry extract and saponin fraction of *** before and after ***:Saponin fraction showed an increase of 32.8%total ***-performance liquid chromatography-mass spectrometry analysis showed the presence of saponins in the obtained *** evaluation by REM demonstrated that samples before and after release presented antiglycation activity similar to bovine serum albumin treated with ***,samples inhibited AGE formation,highlighting treatment with saponin fraction after release(89.89%).Antioxidant tests demonstrated antioxidant activity of the *** dry extract before encapsulation presented the highest activities in DPPH(92.00%)and TBARS(32.49%)*** fraction before encapsulation in FRAP test(499μmol Trolox equivalent per gram of dry sample)and NO test(15.13μmol nitrite formed per gram of extract)presented the highest ***:This study presen

关键词： Glycation Microencapsulation Oxidative stress Saponins Tribulus terrestris

Ergatoid reproductives in the Neotropical termite Nasutitermes aquilinus (Holmgren) (Blattaria: Isoptera: Termitidae): developmental origin, fecundity, and genetics

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Insect Science 2020年第6期27卷 1322-1333页

作者： Iago Bueno da silva Ives Haifig Edward LVargo Fabiana Elaine Casarin Marcelo Luiz da Mota Juliana Toledo Lima Ana Maria costa-Leonardo Laboratorio de Cupins Departamento de BiologiaInstituto de BiocienciasUniversidade Estadual Paulista-UN ESPRio ClaroSPBrazil Centro de Ciencias Naturais e Humanas Universidade Federal do ABCSao Bernardo do CampoSPBrazil Department of Entomology Texas A&M UniversityCollege StationTexasUSA Departamento de Ciencias Biologicas Universidade Federal de Sao Paulo-UNIFESPDiademaSPBrazil Instituto de Ciencias Agrarias Universidade Federal de Uberlandia—UFUMonte CarmeloMGBrazil Centro de Estudos em Recursos Naturais Universidade Estadual de Mato Grosso do SulDouradosMSBrazil

Termite colonies are usully headed by primary reproductives,which estab-listh nests during the swar ming ***,secondary reproductives may develop in some specics and become supplementary or replacement breeders,extending colony *** we investigate the developmental origin,fecundity and genetic characterizaion of ergatoid reproductives in the Neotropical termite Nasuitermes aquilinus(Holmgren),using morphometrical and histological techniques,five micosiallitle loci and the COI mitochondrial *** measurements performed on 208 apterous individuals of Nuauidius revealed 10 groups,including ergatoid females,which developed from major workers through two successive *** were characterized by the presence of imaginal features such as eyes andl wing *** difentiation of these features was correlated to physogastric development in these ergatoids,Histology revealed ooeytes in all matu-ration sages in worker-derived reproductives of N aquidinus,presence of nonflagellate spermatozoa inside the spermatheea,and royal fa ***,ergatoid reproduwetives were reproductively *** to the genotypes of 221 individuals from 11 nests,and mitochondrial haplotypes of 43 ergatoids,73%of the colomies were simple families,whereas 27%were extendbed *** the oecurenee of related reproductives,low inbreeding rates were detected within and among *** values could be explained given that sib mating itself cannot result in a higher inbreeding rate but depend on several factors discussed in *** is the first study to investigate the genetic structure of termite colonies influenced by the development of ergatoids and further investigations are encouraged 10 understand the inflwence of these reproductives on colony lifespan.

关键词： breeding syslem caste ifrentiation COI genotyping micosallites reproduction