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Rotational Oscillation Effect on Flow Characteristics of a Circular Cylinder at Low Reynolds Number

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World Journal of Mechanics 2015年第10期5卷 195-209页

作者： alice rosa da silva Aristeu da Silveira-Neto Antonio Marcos Goncalves de Lima School of Civil Engineering Federal University of UberlandiaUberlandiaBrazil School of Mechanical Engineering Federal University of UberlandiaBrazil

Two dimensional numerical simulations of flow around a rotationally oscillating circular cylinder were performed at Re = 1000. A wide range of forcing frequencies, fr, and three values of oscillation amplitudes, A, are considered. Different vortex shedding modes are observed for a fixed A at several values of fr, as well as for a fixed fr at different values of A. The 2C mode of vortex shedding was obtained in the present study. It is important to point out that this mode has not been observed by other investigators for rotationally oscillating case. Also, it is verified that this mechanism has great influence on the drag coefficient for high frequency values. Furthermore, the lift and pressure coefficients and the power spectra density are also analyzed.

关键词： Rotationally Oscillating Cylinder Vortex Shedding Modes Drag Coefficient

Oregano and Rosemary Essential Oils in Collagen Fiber and Polyvinyl Alcohol Films: Application as Biodegradable Active Packaging for Ready-to-Eat Meat Products

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Food and Nutrition Sciences 2025年第1期16卷 1-27页

作者： Suslin Raatz Thiel Cássio Poerschke Rodrigues José Dilson Francisco da silva Mari Silvia Rodrigues de Oliveira Stephanie Reis Ribeiro rosa Cristina Prestes Ernesto Hashime Kubota Roger Wagner Renius Mello Department of Food Science and Technology Universidade Federal de Santa Maria Rio Grande do Sul Brazil

Developing packaging using biomaterials offers a solution to the problem of solid plastic waste in urban areas. However, selecting suitable materials remains challenging, particularly when the packaging is intended for food products with high moisture content, such as meat. In response to this challenge, a novel film comprising a blend of collagen fiber and polyvinyl alcohol, supplemented with varying concentrations of oregano and rosemary essential oils, was developed. The mechanical properties, in vitro antioxidant activity, and chemical composition of these collagen fiber and polyvinyl alcohol films, enhanced with oregano and rosemary essential oils, were thoroughly characterized. The compounds γ-terpinene and ρ-cymene played a significant role in the antioxidant activity of the packaging. The impact of this active packaging on the quality of sliced mortadella was evaluated over 0, 3, 6, and 9 days of refrigeration. Time significantly influenced most of the variables examined. The concentration of essential oils (0%, 2%, 4%, and 6%) significantly affected the moisture level, water activity, pH, and Escherichia coli count in the packaged product. For lipid oxidation analysis, the type of essential oil proved significant, with oregano essential oil demonstrating superior activity. A pro-oxidant effect was noted in products with 6% rosemary essential oil. Packages containing essential oils from oregano and rosemary exhibited lower E. coli counts. Films enriched with essential oils showed a higher rate of biodegradation.

关键词： Lipid Oxidation Escherichia coli Principal Component Analysis Bioactive Compounds Shelf Life Mechanical Properties

Fractionation of rare earth and other trace elements in crabs,Ucides cordatus,from a subtropical mangrove affected by fertilizer industry

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Journal of Environmental Sciences 2017年第4期29卷 69-76页

作者： alice Bosco-Santos Wanilson Luiz-silva Emmanoel Vieira da silva-Filho Monique Dias Corrêa de Souza Elton Luiz dantas Margareth Sugano Navarro State University of Campinas (UNICAMP) Institute of Geosciences Department of Geology and Natural Resources Campinas Sao Paulo 13083870 Brazil . Fluminense Federal University (UFF) Institute of Chemistry Department of Geochemistry Niteroi Rio de Janeiro 24900970 Brazil University of Brasília(UnB) Institute of Geosciences Department of Geology Brasflia Distrito Federal 70910900 Brazil

Fractionation of rare earth elements（REE） and other trace metal concentrations（Th, U, Cd,Cr, Cu, Ni, Pb, and Zn） between mangrove sediments and claw muscles and shells of male crabs（Ucides cordatus） from a subtropical estuary highly impacted by fertilizer industry activities was investigated. This is the first record of REE distribution in these organisms,and the results showed higher accumulations of these metals, U and Th in shells, probably related to the replacement of Ca during molting. Contents of Cd, Cr and Ni were similar in both tissues, but Cu, Zn and Pb were mostly accumulated in the claw muscle with concentrations above those considered safe for human consumption according to the Brazilian legislation. REE fractionation was different in the analyzed tissues being softer in the shells. The results provided evidences that the water absorbed during molting controls the chemistry of REE in shells. In contrast, the chemistry of REE in the claw muscle, in which was observed preferential absorption of light REE, is controlled by diet. REE fractionation obtained for the claw muscles was closely correlated to the observed in the contaminated substrate and in materials related to the production of phosphate fertilizers（contamination source）, which supports their transference to this Ucides cordatus tissue without fractionation by the ingestion of sediments. Our results showed the potential use of crab tissues for monitoring REE and trace element sources in mangrove areas, with claw muscle exhibiting the contaminant source fingerprint.

关键词： Rare earth elements Trace metals Fertilizer contamination Crabs

Litter removal impacts on soil biodiversity and eucalypt plantation development in the seasonal tropics

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Journal of Forestry Research 2023年第3期34卷 735-748页

作者： Jonas Inkotte Barbara Bomfim Sarah Camelo da silva Marco Bruno Xavier Valadão Márcio Gonçalves da rosa Roberta Batista Viana Alcides Gatto Reginaldo SPereira Department of Forestry Engineering University of BrasiliaBrasíliaDistrito FederalBrazil Climate and Ecosystem Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA SESI/SENAI Social Service Industry Santa Catarina StateChapecóBrazil

The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic ***,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and *** two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area *** litterfall rates in juvenile and mature stands did not change with litter removal over the study *** litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control *** wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in *** years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to *** the mature stand,total cation exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional scaling ordination revealed an increased homogeneity in epigeic fauna where litter was ***,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control p

关键词： Cerrado Nutrient cycling Soil ecology Soil epigeic fauna Plantation management

A Model Structured in Classes for the Study of Student Population Evolution

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上海大学学报（自然科学版） 2014年第2期20卷 127-137页

作者： PEREIRA Edgar rosa Cecilia silva Jacques Department of Mathematics Universidade Federal do Rio Grande do Norte Department of Mathematics Instituto Politecnico da Guarda Department of Mathematics Universidade Federal do Rio Grande do Sul

This paper presents an application of a metapopulation model structured in classes for the study of population evolution of a network of *** global dynamics are considered in two parts,the local,where the evolution for each grade in a cycle is accounted,and the metapopulation or the movement of students between *** of the model is presented.

关键词：应用数学数学分析数学理论数学概念

Rainwater Harvesting in Multifamily Social Interest Housing

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Journal of Civil Engineering and Architecture 2015年第10期9卷 1261-1268页

作者： Regina Lucia Melo de Oliveira Marilia Karla da silva Santos Simone rosa da silva Polytechnic School of the University of Pernambuco Recife 50720-001 Brazil

This study evaluated the reduction of water consumption in a SIH （social interest housing） complex from the simulation of implanting a rainwater harvesting system. The methodology consisted of characterization of the case study, survey data of water consumption and data of precipitation in the area, on-site visits to define the average consumption and monthly water distribution, and sizing of a rainwater harvesting tank following the Netuno Program. It was obtained 22.500 L as the ideal volume for the tank, supplying the demand for drinkingwater in 32%, although the reduction in the drinking water bills would be minor, since the object of the case study is considered SIH, and residents pay a fixed fee for consuming up to 10 m3 per month. Therefore, it becomes necessary to analyze this situation from a sustainable and environmental perspective, and the benefits are no longer only economic, but rather they take on a more comprehensive social dimension.

关键词： Rational use of water rainwater harvesting rainwater collection social interest housing.

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Stem cells and pain

World Journal of Stem Cells 2023年第12期15卷 1035-1062页

作者： Matheus Deroco Veloso da silva Maiara Piva Geovana Martelossi-Cebinelli Mariana Stinglin rosa Ribas Beatriz Hoffmann Salles Bianchini Olivia K Heintz Rubia Casagrande Waldiceu A Verri Jr Department of Pathology Laboratory of PainInflammationNeuropathy and CancerState University of LondrinaLondrina 86057-970ParanáBrazil Morningside Graduate School of Biomedical Sciences University of Massachusetts Chan Medical SchoolWorcesterMA 01655United States Department of Pharmaceutical Sciences Center of Health ScienceState University of LondrinaLondrina 86038-440ParanáBrazil Department of Pathology Laboratory of PainInflammationNeuropathy and CancerCenter of Biological SciencesState University of LondrinaLondrina 86057-970ParanáBrazil

ain can be defined as an unpleasant sensory and emotional experience caused by either actual or potential tissue damage or even resemble that unpleasant *** years,science has sought to find treatment alternatives,with minimal side effects,to relieve ***,the currently available pharmacological options on the market show significant adverse ***,the search for a safer and highly efficient analgesic treatment has become a *** cells(SCs)are non-specialized cells with a high capacity for replication,self-renewal,and a wide range of differentiation *** this review,we provide evidence that the immune and neuromodulatory properties of SCs can be a valuable tool in the search for ideal treatment strategies for different types of *** the advantage of multiple administration routes and dosages,therapies based on SCs for pain relief have demonstrated meaningful results with few ***,there are still more questions than answers when it comes to the mechanisms and pathways of pain targeted by ***,this is an evolving field that merits further investigation towards the development of SCbased analgesic therapies,and this review will approach all of these aspects.

关键词： Inflammation Neuropathy Nociceptive Pain Pain treatment Stem cells

Prevalence of congenital cytomegalovirus infection in preterm,small for gestational age and low birth weight newborns:characteristics and cytokines profile

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World Journal of Pediatrics 2022年第7期18卷 498-504页

作者： Janaina Fortes Lino Llian Martins Oliveira Diniz Debora Marques de Miranda daniela Valadao Freitas rosa Nathalia Gualberto Souza e silva Eduardo de Souza Nicolau Larissa Goncalves Rezende Lais silva Carvalho Marianna Fischer de Paula Lopes Luisa Petri Correa Gabriela Mafra de Oliveira Flavia Miranda da silva Alves Lorena Batista Pascoal Erika Lima Dolabella Teixeira da Costal Leni Marcia Anchieta Roberta Maia de Castro Romaneli Odete Valadares Maternity Hospital Belo HorizonteBrazil Pediatrics Department.Faculy of Medice of Federal University of Minas Gerais Belo Horizonte.Brazil Molecular Laboratory of the INCT-MM.Faculy of Medicine.Federal University of Minas Gerais-UFMG.Belo Horizonte Brazil Faculty of Medicine.Federal University of Minas Gerais-UFMG Belo Horizonte.Brazil Risoleta Tolentino.Neves University Hospital's Maternity Belo HorizonteBrazil Sofia Feldman Maternity Hospital Belo HorizonteBrazil Hospital das Clinicas Maternity-Federal University of Minas Gerais.Belo Horizonte Brazil Pediatrics Department of Federal University of Minas Gerais School Medicine.Minas Gerais.Av Professor Alfredo Balena 190.Belo Horizonte 30130-100Brazil

Cytomegalovirus is the most frequent agent of congenital viral infections,affecting approximately 0.2%-2.4%of live births in different countries[1-7].Universal screening for congenital cytomegalovirus infection in newborns is not a standard practice considering cost-benefit issues and viabil-ity of diagnostic ***,most newborns are asympto-matic and there is no effective treatment for this population[2-5].

关键词： weight birth characteristics

Effect of Concentration and Residence Time of Joncryl■ADR4368 on Melt Processability of Poly(3-hydroxybutyrate)

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Journal of Renewable Materials 2024年第12期12卷 2079-2094页

作者： Jéssica da silva Chagas JoséElson Soares Filho Natália Fernanda Inocêncio silva Marcelo Massayoshi Ueki Eliton Souto de Medeiros Renate Maria Ramos Wellen Mauricio Pinheiro de Oliveira Gelsoneide da silva Gois Yêda Medeiros Bastos de Almeida Amélia S.F.Santos Post-Graduation Program in Materials Engineering(PPCEM) Federal University of Paraíba(UFPB)João PessoaPB 58051-900Brazil Laboratory of Materials and Biosystems(LAMAB) Federal University of Paraíba(UFPB)João PessoaPB 58051-900Brazil Department of Materials Engineering Federal University of Sergipe(UFS)Jardim Rosa ElzeSão CristóvãoSE 49100-000Brazil Institute of Science and Technology Federal University of São Paulo(UNIFESP)São Josédos CamposSP 12231-280Brazil Department of Chemical Engineering Federal University of Pernambuco(UFPE)Cidade UniversitáriaRecifePE 50670-901Brazil

Poly(3-hydroxybutyrate)(PHB)is a biothechnological and biodegradable thermoplastic polymer from the polyhydroxyalkanoates(PHAs)family,whose chain regularity,high molecular weight,and physical and mechanical properties comparable to polypropylene(PP)are characteristics that have made PHB a prominent commercial ***,its susceptibility to thermal degradation and hydrolysis has limited many *** address the challenges associated with processing,a random copolymer of 95.86 mol%3-hydroxybutyrate and 4.14 mol%3-hydroxyvalerate(referred as PHB)was compounded without(neat PHB)and with 0.25,0.5,1,and 1.5 wt%of chain extender(Joncryl■ADR 4368),consisting of multifunctional epoxy groups,and melt mixed in an internal mixer at 170℃,50 rpm,and residence times of 5,10,and 15 *** effect of chain extender concentration and residence time on the effectiveness of Joncryl■ADR 4368 to recover the pristine PHB properties were investigated through torque rheometry,melt flow index(MFI),differential scanning calorimetry(DSC),tensile testing,and thermogravimetric *** results indicated that an increase in residence time strongly influenced the prevalence of thermomechanical degradation reactions over chain extension reactions of PHB during processing in the molten *** residence times favored chain extension,while longer times favored chain *** trend led to no enhancement of PHB mechanical properties processed for 10 and 15 min,regardless of additive content *** flow index,thermogravimetric analysis and tensile strength exhibited an asymptotic behavior with the increase in additive concentration,exhibiting a noteworthy improvement in tensile strength and temperature at the highest rate of thermal degradation(TMAX),and a decrease in melt flow index of neat PHB with only 0.25 wt%of additive mixed for 5 *** results found in this work allow additional data for processing PHB by manipulating the ratios of multifunctional chain

关键词： PHB chain extender degradation epoxy groups viscosity