1,891 research outputs found

    Valorization of sugarcane bagasse ash: Producing glass-ceramic materials

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    Some aluminosilicates, for example mullite and wollastonite, are very important in the ceramic and construction industries. The most significant glass-ceramic for building applications has wollastonite as the main crystal phase. In this work we report on the use of sugarcane bagasse ash (SCBA) to produce glass-ceramics with silicates as the major crystalline phases. The glasses (frits) were prepared by mixing ash, limestone (calcium and magnesium carbonates) and potassium carbonate as the fluxing agent. X-ray fluorescence was used to determine the chemical composition of the glasses and their crystallization was assessed by using thermal analysis (DTA/DSC/TGA) and X-ray diffraction. The results showed that glass-ceramic material can be produced with wollastonite as the major phase, at a temperature lower than 900 °C.We are grateful to PROPE/UNESP/SANTANDER for the post-doctoral scholarship awarded to Dr. Teixeira, to FAPESP (2008/04368-4) for financial support of this project and also to FUNDUNESP for financial aid.Peer reviewe

    Nucleation kinetics of crystalline phases from a kaolinitic body used in the processing of red ceramics

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    The crystallization kinetics of red ceramic raw material from the western part of São Paulo State, Brazil, was examined by differential thermal analysis (DTA) and X-ray diffraction (XRD). The chemical composition of the clay sample was determined by X-ray fluorescence (XRF). Non-isothermal crystallization kinetic methods have been applied to the study of the mechanism of crystallization in this kaolinitic material. The exothermic peak shifted to higher temperatures (945 to 974 °C) with increasing heating rate (10 to 50 °C/min). The average activation energies determined by the Kissinger method (787 ± 85 kJ/mol) and the Ligero method (721 ± 32 kJ/mol) are in agreement. The Avrami constant n obtained by the Ligero method and the m parameter (Matusita method) values were between 1 and 1.5, which indicate a three-dimensional crystal growth with polyhedral morphology and surface nucleation as the dominant mechanism. X-ray diffraction data indicate that this activation energy is not associated with the crystallization of mullite. Scanning electron microscopy (SEM) images of fired (1000 and 1190 °C) samples show their densification during the sinterization process.The authors thank FUNDUNESP and FAPESP (2008/04368-4) for financial support of this work. We also are grateful to PROPE/UNESP/SANTANDER for Dr. Teixeira's post-doc scholarship in MadridPeer reviewe

    APLICAÇÃO DE RECURSOS ECONÔMICOS NA UNIVERSIDADE FEDERAL DE SANTA CATARINA (UFSC): uma análise a partir da teoria econômica institucional

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    As instituições federais de ensino superior (IFES) apresentam diferentes especificidades em relação às demais instituições públicas, o que exige de seus gestores capacidades específicas. Na esfera pública, bem como nas IFES, cresce a necessidade de se conhecer a aplicação de recursos econômicos. A presente pesquisa teve como objetivo geral: Compreender como ocorre a aplicação dos recursos econômicos na UFSC. Foi realizado um estudo de caso com abordagem qualitativa. O processo de coleta de dados envolveu dados primários, por meio de entrevistas semiestruturada e dados secundário, com pesquisa documental e bibliográfica. Foram entrevistados dois gestores da Seplan. O atual Secretários da Planejamento e Orçamento e o ocupante do cargo nos anos de 2014 a 2016. Com os resultados da pesquisa foi possível conhecer as fontes de recursos econômicos presentes na UFSC, bem como entender a aplicação de recursos econômicos na UFSC. Destaque, a gestão financeira no seguimento de procedimentos habituais enraizados e compartilhados em respeito às leis, normas, regras e convenções estabelecidas, em linha com os preceitos postos por Veblen e North, representantes da economia institucional estudados

    Seroprevalence of bovine leptospirosis in reproductive-age female bovines in the state of São Paulo, Brazil

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    O presente estudo teve como objetivo determinar a soroprevalência da leptospirose bovina em fêmeas em idade reprodutiva do Estado de São Paulo, estratificado em sete regiões produtoras. Foram utilizados o delineamento estatístico, as amostras sorológicas e as informações contidas nos questionários empregados no Programa Nacional de Controle e Erradicação da Brucelose e Tuberculose (PNCETB), instituído pelo Ministério da Agricultura, Pecuária e Abastecimento, considerando-se a utilização de fêmeas bovinas com idade '> OU =' a 24 meses (excluindo-se machos), diferentes tipos de produção, práticas de manejo, finalidades de reprodução, tamanho dos rebanhos e sistema de comercialização. Realizou-se a Soroaglutinação Microscópica (SAM) em 8.216 amostras sorológicas de animais provenientes de 1.021 propriedades. De acordo com os resultados obtidos, a infecção por Leptospira spp. ocorre em todo o Estado de São Paulo, com soroprevalência de 49,4% (IC 95% = 44,4%-54,4%) nas fêmeas bovinas em idade reprodutiva e em 718 (71,3%; IC 95% = 68,5%-74%) das propriedades analisadas. O sorovar Hardjo (46%) e sua associação com o sorovar Wolffi (21%) foram prevalentes entre o total de animais sororeagentes, seguidos pelos sorovares Shermani (8,9%), Autumnalis (4,4%) e Grippotyphosa (3,9%). Leptospira spp. está distribuída por todo estado e independe do tipo de exploração, manejo e das práticas de reprodução adotadas nos rebanhosThe objective of the present study was to determine the seroprevalence of bovine leptopirosis in São Paulo State, stratified in seven cattle production regions. It was based on the statistic delineation, serological samples and responses to the survey employed in the National Program for Control and Eradication of Brucelosis and Tuberculosis established by Ministry of Agriculture (2001). From the herds selected, serological analysis was only conducted on the cows '> OU =' 24 months old (excluding the males). The study took into consideration the herd size, the type of productive exploration, the reproductive handling, bovine practices and the commercialization system. The microscopic agglutination test (MAT) was applied on 8,216 serum samples from 1,021 different farms. The results showed that leptospirose infection occurs all over the seven regions of São Paulo State with 49.4% (CI 95% = 44.4-54.4%) animal seroprevalence and in 718 (71.3%; CI 95% = 68.5-74.0%) of the herds analyzed. Hardjo (46%) was the prevalent serovar for all the animals examined, followed by the Hardjo/Wolffi association (21%), Shermani (8.9%), Autumnalis (4.4%) and Grippotyphosa (3.9%). Leptospira spp. is present in all regions of the State of São Paulo and its occurrence is independent of the handling conditions and reproductive practices adopted in the herd

    Seroprevalence of leptospirosis in reproductive-age bovine females in the state of Bahia, Northeastern Brazil

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    O objetivo do presente trabalho foi determinar a soroprevalência da leptospirose em fêmeas bovinas em idade reprodutiva no Estado da Bahia. A amostragem foi delineada para a determinação da prevalência de propriedades positivas (focos) e de animais soropositivos para a leptospirose. O Estado foi dividido em quatro regiões ou estratos amostrais, nos quais foramexaminadas 10.823 fêmeas bovinas com idade ≥24 meses distribuídas em 1.414 propriedades. A reação de Soroaglutinação Microscópica (SAM), empregando 23 sorovares de Leptospira spp. como antígenos, foi utilizada como teste diagnóstico. O rebanho foi considerado foco quando apresentou pelo menos um animal soropositivo. As prevalências de foco e de animais soropositivos no Estado foram de 77,93% [IC 95% = 75,73% – 79.99%] e 45,42% [IC 95% = 42,00% – 48,88%], respectivamente.O sorovar mais frequente foi o Hardjo (Hardjoprajitno), em 34,49% [IC 95% = 31,93% – 37,14%] daspropriedades positivas e 14,95% [IC 95% = 12,59% - 17,67%] de animais soropositivos de diferentes regiõesThe aim of this work was to determine the seroprevalence of leptospirosis in reproductive-age bovine females in Bahia State, Northeastern Brazil. The sampling was delineated for the determination of the prevalence of seropositive animals as well as herds positive for bovine leptospiroses (foci). The state was divided into 4 regions or sampling strata in which 10,823 bovine females aged ≥24 months allocated in 1,414 herds were sampled. The microscopic agglutination test (MAT), using 23 Leptospira spp. serovars as antigens, was employed as a diagnostic test. The herd was considered positive if at least one animal was seropositive. The prevalences of positive herds and seropositive animals in the state were 77.93% [75.73%–79.99%] and 45.42% [42.00%–48.88%], respectively. Serovar Hardjo (Hardjoprajitno) was the most frequent, with 34.49% [31.93%–37.14%] of positive herds and 14.95% [12.59%–17.67%] of seropositive animals in the different region

    Characterization and pattern recognition of color images of dermatological ulcers: a pilot study

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    We present color image processing methods for the char\-ac\-te\-ri\-za\-tion of images of dermatological lesions for the purpose of content-based image retrieval (CBIR) and computer-aided di\-ag\-no\-sis. The intended application is to segment the images and perform classification and analysis of the tissue composition of skin lesions or ulcers, in terms of granulation (red), fibrin (yel\-low), necrotic (black), callous (white), and mixed tissue composition. The images were analyzed and classified by an expert dermatologist following the red-yellow-black-white model. Automatic segmentation was performed by means of clustering using Gauss\-ian mixture modeling, and its performance was evaluated by deriving the Jaccard coefficient between the automatically and manually segmented images. Statistical texture features were derived from cooccurrence matrices of RGB, HSI, L^*a^*b^*, and L^*u^*v^* color components. A retrieval engine was implemented using the k-nearest-neighbor classifier and the Euclidean, Man\-hat\-tan, and Chebyshev distance metrics. Classification was performed by means of a metaclassifier using logistic regression. The average Jaccard coefficient after the segmentation step between the automatically and manually segmented images was 0.560, with a standard deviation of 0.220. The performance in CBIR was mea\-sured in terms of precision of retrieval, with average values of up to 0.617 obtained with the Chebyshev distance. The metaclassifier yielded an average area under the receiver operating char\-ac\-ter\-is\-tic curve of 0.772

    Efeito do Levamisole sobre a resposta imunitária de cobaias tratados com vacina antiaftosa inativada

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    The protection titer of an inactivated tricalent “O", “A" and “C” Foot-and-Mouth disease (FMD) vaccine was assayed in two groups of 96 guinea pigs, one of them received levamisole at an animal daily dose of 2,5 mg/kg during the three days starting the day of the FMD vaccination and the other one was used as control. The range of vaccine dilutions was 10-0, OOO, 10-602, 10-1, 204 e 10-1,806 and animals were challenged at 21 days after vaccination with 158 DG50 of FMD virus type “C” Waldmann. Although no significant difference was detected between the protection vaccine titer of the two groups, a paired analysis of each vaccine dilution result revealed a favorable effect of levamisole when the vaccine was used at a dilution 10-1,806 .O título de proteção de uma vacina antiaftosa trivalente (O-A-C) inativada foi restabelecido em dois grupos de 96 cobaios, um dos quais recebeu Levamisole na dose diária de 2,5 miligramas por quilo durante três dias consecutivos a partir do momento da vacinação e o outro foi utilizado como controle. A vacina foi empregada nas diluições 10-0, OOO, 10-602, 10-1, 204 e 10-1,806 e os animais desafiados aos 21 dias após a vacinação com 158 DG50 do vírus “C” Waldmann da febre aftosa. Embora não tenha sido verificada uma diferença significante entre os títulos de proteção da vacina nos dois grupos, uma análise pareada dos valores obtidos com cada uma das diluições da vacina revelou um efeito favorável do Levamisole apenas quando a vacina foi empregada na diluição 10-1,806

    Use of Leptospira spp. strains isolated in Brazil in the microscopic agglutination test applied to diagnosis of leptospirosis in cattle herds in eight brazilian states

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    Sarmento A.M.C., Azevedo S.S., Morais Z.M., Souza G.O., Oliveira F.C.S., Goncales A.P., Miraglia F. & Vasconcellos S.A. 2012. [Use of Leptospira spp. strains isolated in Brazil in the microscopic agglutination test applied to diagnosis of leptospirosis in cattle herds in eight brazilian states.] Emprego de estirpes Leptospira spp. isoladas no Brasil na microtecnica de soroaglutinacao microscopica aplicada ao diagnostico da leptospirose em rebanhos bovinos de oito estados brasileiros. Pesquisa Veterinaria Brasileira 32(7);601-606. Universidade de Sao Paulo, Faculdade de Medicina Veterinaria e Zootecnia, Departamento de Medicina Veterinaria Preventiva e Saude Animal, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508-270, Brazil. E-mail: [email protected] The aim of this study was to investigate the adequacy of the use of autochthonous strains of leptospires isolated in Brazil, added to antigen collection of the microscopic agglutination test (MAT) applied to the diagnosis of bovine leptospirosis. By means of non-probability sampling, 109 farms and 9,820 cattle, females at reproductive age were chosen from 85 municipalities in the states of Goias, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Parana, Rio Grande do Sul, Santa Catarina and Sao Paulo. Among the 9,820 examined animals, 5,806 (59.12%) were reactants at MAT for at least one serovar using the 23 reference serovars. Employing the collection of reference serovars and the ten autochthonous strains, 6,400 (65.24%) reactants and significant difference (p=0.001) was found. The most probable serovars identified by the collection of reference antigens were Hardjo (43.03%), Shermani (20%), Wolfi (9.96%), Grippothyphosa (5.42%) and Pomona (4.28%). With the collection amplified with the ten strains isolated in Brazil, the most probable serovars were Hardjo (31%), Guaricura-M4/84 (22.50%), Shermani (15.43%), Wolffi (4.76%), Grippothyphosa (3.71%) and Autumnalis (3.24%). The serovar Guaricura, strain M4/84, isolated from bovines and buffaloes in the State of Sao Paulo, was ranked as one of the three most probable serovars in the states of Goias, Mato Grosso, Mato Grosso do Sul, Minas Gerais and Sao Paulo. The addition of autochthonous strains to the MAT antigen collection provided the confirmation of the diagnosis of leptospirosis in 594 cattle (6%) which have been classified as non-reactants by the reference collection (p=0.001)
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