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Obtaining Porosity of Concrete Using X-ray Microtomography or Digital Scanner

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Journal of Chemistry and Chemical Engineering 2014年第4期8卷 371-377页

作者： Jose Renato de Castro Pessoa Joel Sanchez Dominguez Gil de Carvalho joaquim teixeira de assis Politechnical Institute of Rio de Janeiro State University Nova Friburgo 28625-570 Brazil

The aim of this work is to determine the porosity of concrete by means of two NDT （non-destructive testing） using digital images. In one test, the images were obtained through X-ray microtomography and for another test via digital scanner. In both of the tests, the images were processed using techniques of mathematical morphology and pixel processing. For both NDT, it was used concrete samples with 20-30 MPa of compressive strength. The results for the porosity were compared with results obtained by the standard test proposed by NBR （Norma Brasileira） 9778 （2005） showing the compatibility between two studied methods and pattern method.

关键词： Concrete porosity X-ray microtomographic images processing matematical morfology.

Comparison of the Internal Structures of Bones by Microtomography

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Journal of Chemistry and Chemical Engineering 2017年第2期11卷 51-54页

作者： Julio Cesar Latini Stutz Joel. Sanchez Dominguez joaquim teixeira de assis deMEC/LEFI/IPRJ Universidade do Estado do Rio de Janeiro 28625-570 Nova Friburgo-RJ Brazil Universidade Estacio de Sa Nova Friburgo Rio de Janeiro Brazil

The use of computed microtomography （***） has revolutionized many areas of research, such as noninvasive, fast and high precision techniques, which allows immediate visualization of internal structures without any risk to the object of study. ~tCT is widely accepted for medical diagnostics, is also important for purposes of zoological research and paleontological. In this work, we used the μCT to investigate the internal structure of bones from mammalian and poultry. We studied the bones of rats and quail. Through microtomography images, we observed that the bones of the poultry have a bony structure in the form of a trellis that is not present in bones of mammals. These trellises bony is an evolutionary adaptation that allowed the bones of the birds to become longer and lighter maintaining its strength. It was also observed that the percentage of the trabecular area in poultry is almost half of that observed in mammals. The results obtained validate the use of μCT as a technique that allows the study of bone structures in small samples, enabling to explore the morphological differences between the bones of those species.

关键词： Microtomography bones X-ray.

Calculation of Percentage of Coarse Aggregate Present in Concrete Using Processing of Digital Images Obtained with a Commercial Scanner

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Journal of Chemistry and Chemical Engineering 2015年第2期9卷 136-139页

作者： Jose Renato de Castro Pessoa Joel Sanchez Dominguez Rodrigo Erthal Wilson Vanussa da Silva Charles Gil de Carvalho joaquim teixeira de assis Politechnical Institute of Rio de Janeiro State University Nova Friburgo 28625-570 Brazil Estacio de Sa University Nova Friburgo 28611-135 Brazil Federal Fluminense University Itaocara 28470-000 Brazil

This paper presents a method for determining the percentage of coarse aggregate in concrete specimens by image processing. The test pieces were produced with the aim of obtaining images of their cross sections through a scanner table. In order to increase the contrast between mortar and coarse aggregate the sliced surfaces were treated with the phenolphthale in solution. The images obtained in the scanner were processed in a program developed with MATLAB （matrix laboratory）. The average coarse aggregate in each section and the mean of coarse aggregate per test body were calculated. With the results, it was revealed that the method returned satisfying results when compared to the original trace of the concrete.

关键词： Concrete image processing characterization of concrete.

Structure and genetic diversity of natural populations of Guadua weberbaueri in the southwestern Amazon,Brazil

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Journal of Forestry Research 2021年第2期32卷 755-763页

作者： Glória da Silva Almeida Leal Fabrício assis Leal Hugo teixeira Gomes Anderson Marcos de Souza Sabina Cerruto Ribeiro Jonny Everson Scherwinski-Pereira Centro Multidisciplinar Universidade Federal do AcreCruzeiro do SulAcreBrazil Universidade de Brasília BrasíliaDistrito FederalBrazil Centro de Ciências Biológicas e da Natureza Universidade Federal do AcreRio BrancoAcreBrazil Centro de Pesquisa e Aplicação de Bambu e Fibras Naturais Universidade de Brasília–CPAB/UnBBrasíliaDistrito FederalBrazil Embrapa Recursos Genéticos e Biotecnologia Av.W5 Norte(final)PqEBBrasíliaDistrito Federal 70770-917Brazil

The Brazilian state of Acre has an extensive natural reserve of bamboo,making it one of the largest in loco gene *** aim of this study was to characterize the structure and genetic diversity of Guadua weberbaueri *** two populations,one native(FAPB)and the other anthropized(FAPBA),using ISSR *** results show that the FAPB population exhibited higher values for all estimates of population ***,the FAPBA population also showed high heterozygosity,corroborated by estimated gene flow(Nm=3.9)between the *** study of the association between Nei’s genetic distances and the geographic distances between the populations were significantly correlated(r=0.45,p=0.01),corroborated by the dendrogram revealing two distinct groups corresponding to the collection sites,without mixing classes between populations in the same *** for the coancestry coefficient,pairs of individuals in the first distance class were positive and significant,indicating that plants that are geographically closer share common alleles with a frequency greater than by chance,which means that there is a tendency that geographically closer individuals are *** presented similar genetic structure when the geographical distance between them was up to 56 m for FAPB and up to 156 m for *** was concluded that anthropized environments exhibit less genetic diversity than native environments,inferring risks for species conservation if appropriate and planned management techniques are not adopted.

关键词： Guadua Bamboo Genetic diversity Amazon rainforest Anthropized and native populations Underutilization plants

Bone marrow-derived monocyte infusion improves hepatic fibrosis by decreasing osteopontin,TGF-β1,IL-13 and oxidative stress

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World Journal of Gastroenterology 2017年第28期23卷 5146-5157页

作者： Veruska Cintia Alexandrino de Souza Thiago Almeida Pereira Valéria Wanderley teixeira Helotonio Carvalho Maria Carolina Accioly Brelaz de Castro Carolline Guimaraes D’assuncao Andreia Ferreira de Barros Camila Lima Carvalho Virgínia Maria Barros de Lorena Vláudia Maria assis Costa Alvaro Aguiar Coelho teixeira Regina Celia Bressan Queiroz Figueiredo Sheilla Andrade de Oliveira Centro de Pesquisas Aggeu Magalhaes Fundacao Oswaldo Cruz Immunopathogenesis Section Laboratory of Parasitic DiseasesNational Institute of Allergy and Infectious DiseaseNational Institutes of HealthBethesdaMDUSA and Laboratório de Doencas Parasitárias e infecciosasFaculdade de MedicinaUniversidade Federal de Minas Gerais departamento de Morfologia e Fisiologia Animal Universidade Federal Rural de Pernambuco departamento de Biofísica e Radiobiologia Universidade Federal de Pernambuco Centro Acadêmico de Vitória Universidade Federal de Pernambuco departamento de Medicina Tropical Universidade Federal de Pernambuco

To evaluate the therapeutic effects of bone marrow-derived CD11b+CD14+ monocytes in a murine model of chronic liver *** liver damage was induced in C57BL/6 mice by administration of carbon tetrachloride and ethanol for 6 mo. Bone marrow-derived monocytes isolated by immunomagnetic separation were used for therapy. The cell transplantation effects were evaluated by morphometry, biochemical assessment, immunohistochemistry and enzyme-linked immunosorbent ***11b+CD14+ monocyte therapy significantly reduced liver fibrosis and increased hepatic glutathione levels. Levels of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-6 and IL-1β, in addition to pro-fibrotic factors, such as IL-13, transforming growth factor-β1 and tissue inhibitor of metalloproteinase-1 also decreased, while IL-10 and matrix metalloproteinase-9 increased in the monocyte-treated group. CD11b+CD14+ monocyte transplantation caused significant changes in the hepatic expression of α-smooth muscle actin and *** therapy is capable of bringing about improvement of liver fibrosis by reducing oxidative stress and inflammation, as well as increasing anti-fibrogenic factors.

关键词： Monocytes Bone marrow mononuclear cells Cell therapy Macrophages Glutathione Liver fibrosis

Simulation of X-ray Diffraction Line Broadening Caused by Stress Gradients and determination of Stress Distribution by Fourier Analysis

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Journal of Chemistry and Chemical Engineering 2012年第9期6卷 838-842页

作者： Vladimir Ivanovltch Monin joaquim Teixera de assis Susana Marrero Iglesias Politechnical Institute of Rio de Janeiro State University Nova Friburgo-RJ Brazil Santa Cruz State University llheus Brazil

Different physical, mechanical and chemical processes, such as： ion implantation, oxidation, nitridation and others create on the surface of materials residual stress state, characterized by high level and strong gradient. X-ray diffraction method widely used for stress measurements has some difficulties in interpretation of experimental data, when the depth of X-ray penetration is compared with thickness of surface layer where inhomogeneous stress distribution is localized. Early it has been shown by authors that diffraction line broadening occurs when analyzed surface is characterized by strong gradient. The interest to study the diffraction line broadening is connected to the possibility of obtaining information about parameters of surface stress distribution. In the present paper the convolution and deconvolution concepts of Fourier analysis were applied to study X ray diffraction line broadening caused by surface stress gradients. developed methodology allows determining of stress distribution in superficial layers of materials.

关键词： Stress gradient X-ray diffraction computer simulation Fourier analysis.

Colorimetric indicators of açaíanthocyanin extract in the biodegradable polymer matrix to indicate fresh shrimp

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Food Bioscience 2022年第4期48卷 601-612页

作者： Samiris Cocco teixeira Taíla Veloso de Oliveira Rafael Resende assis Silva Alane Rafaela Costa Ribeiro Paulo Cesar Stringheta Thaís Caroline Buttow Rigolon Marcos Roberto Moacir Ribeiro Pinto Nilda de Fatima Ferreira Soares Laboratory of Food Packaging Department of Food TechnologyFederal University of ViçosaViçosaMG36570-900Brazil department of Materials Science and Engineering Federal University of S˜ao CarlosS˜ao CarlosSP13565-905Brazil Laboratory of Pigments and Bioactive Compounds Federal University of ViçosaViçosaMG36570-900Brazil Federal Institute of Espírito Santo Venda Nova do ImigranteES29375000Brazil

Colorimetric indicator or freshness indicators hold great potential to reduce food *** off açaíanthocyanins extract(AE)with different concentrations molars of two plasticizers glycerol(GLY)or triethyl citrate(TEC),for application fresh shrimp,real time were *** AE undergoes a visible pink/violet to green/yellowish color change in response to different pH’s,which is an indicator of microbial spoilage in *** CI were exposed to ammonia,and analyzed through infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),ultraviolet spectroscopy,and visual *** immobilization of the plasticizers into the CA polymer matrices were confirmed through FT-IR spectra and SEM *** vitro chromatic transition of the indicators exposed to ammonia vapors,were visually more perceptible when they were produced with 7.2 mols of GLY or 1.8,3.6,and 7.2 mols of *** the real-time analysis of the application of colorimetric indicators in gray shrimp samples,the indicators that had plasticizers showed perfect color change at the exact time of food *** colorimetric indicators developed in this study using different molar concentrations of plasticizers are simple,effective and a great eco-friendly alternative to chemical sensors already developed so far.

关键词： Cellulose acetate Plasticizer Ammonia sensitivity Glycerol Triethyl citrate Spoilage Fish

Antibacterial enhancement of antibiotic activity by Enterolobium contortisiliquum(Vell.)Morong

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Asian Pacific Journal of Tropical Biomedicine 2017年第10期7卷 945-949页

作者： Zildene de Sousa Silveira Nair Silva Macêdo Thiago Sampaio de Freitas Ana Raquel Pereira da Silva Joycy Francely Sampaio dos Santos Maria Flaviana Bezerra Morais-Braga José Galberto Martins da Costa Raimundo Nonato Pereira teixeira Jean Paul Kamdem Henrique Douglas Melo Coutinho Francisco assis Bezerra da Cunha Laboratorio de Bioprospeccao do Semioarido Universidade Regional do CaririCratoBrazil Laboratorio de Microbiologia e Biologia Molecular Universidade Regional do CaririCratoBrazil Laboratorio de Pesquisas de Produtos Naturais Universidade Regional do CaririCratoBrazil departamento de Ciencias biologicas Universidade Regional do Cariri-URCACratoCEP:63105-000Brazil Programa de Pos-graduacao em Bioprospeccao Molecular Universidade Regional do Cariri–URCACratoBrazil

Objective: To identify the main chemical classes of compounds from aqueous extract of Enterolobium contortisiliquum(E. contortisiliquum) seed bark and to evaluate its antibacterial activity, as well as its potential to increase the activity of antibiotics against strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia ***: Different classes of compounds in the aqueous extract of E. contortisiliquum were evaluated based on the visual changes in the coloration and the formation of precipitate after the addition of specific reagents. The antibacterial activity of the extract and its potential to increase of antibiotic activity of antibiotics drugs, gentamicin and norfloxacin was determined by using the microdilution ***: Our results demonstrated that the following secondary metabolites were presented in E. contortisiliquum seed bark: flavones, flavonols, xanthones, flavononols,chalcones, aurones, flavones and catechins. The extract itself had very low antibacterial activity against all bacterial strains tested(MIC ≥ 1024 μg/m L), but there was an increase in the antibiotic activity of gentamicin and norfloxacin when combined in the subinhibitory concentration(i.e., MIC/8).Conclusions: Our data suggests that E. contortisiliquum seed bark may be an alternative source for new drugs with the potential to increase antibiotic activity against different strains of bacteria.

关键词： Antibiotic activity Enhancement Synergism Chemical compounds Bioactivity

Evaluation of antibacterial and toxicological activities of essential oil of Ocimum gratissimum *** its major constituent eugenol

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Food Bioscience 2022年第6期50卷 2152-2159页

作者： Julio Cesar Silva Raimundo Luiz Silva Pereira Thiago Sampaio de Freitas Janaína Esmeraldo Rocha Nair Silva Macedo Carla de Fatima Alves Nonato Marina Leite Linhares Daniely Sampaio Arruda Tavares Francisco assis Bezerra da Cunha Henrique Douglas Melo Coutinho Sidney Gonçalo de Lima Francisco Nascimento Pereira-Junior Francisco Paulo Araújo Maia Ivo Cavalcante Pita Neto Fabiola Fernandes Galvão Rodrigues George joaquim Garcia Santos department of Biological Chemistry Regional University of CaririR.Cel.Antonio Luis 116163105000CratoCEBrazil University Center Doutor Leão Sampaio Av.Leão Sampaio 40063040000Juazeiro do NorteCEBrazil Research and development Center for Medicines Federal University of CearaR.Coronel Nunes de Melo 100060430275FortalezaCEBrazil Chemistry department Federal University of PiauiCampus Universitário Ministro Petrônio Portella64049550TeresinaPIBrazil Center for Agricultural and Biodiversity Sciences - CCAB Federal University of CaririCratoCearáBrazil CECAPE - College of dentistry Juazeiro do NorteCE63024-015Brazil

The present study aimed to comparatively analyze the antibacterial activity,combined with antibiotics,and toxicological activity of the essential oil of *** *** its major compound,*** phytochemical analysis of the essential oil was performed by gas chromatography coupled with mass *** minimum inhibitory concentration and combined antibiotic activity were performed by *** melanogaster was the model organism chosen to evaluate the toxicological response of *** chromatographic assay showed eugenol as the major compound of the essential oil of *** *** microbiological assays showed that in terms of antibacterial activity,both products showed similar activity,quite significant in Gram-negatives,such as those of strains of Pseudomonas *** results were verified in the modulatory activity,allowing the verification that the bioactivity performed by the essential oil of *** *** mainly influenced by its major *** the EC50 of the compounds varied subtly,the essential oil was less toxic compared to *** information obtained in the present study demonstrates that the essential oil of *** *** a promising antibacterial agent and better tolerated than its majority compound alone,in the model organism ***.

关键词： Antibacterial agents Drosophila melanogaster Eugenol Ocimum gratisismumum L.essential oils