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Faria G.L.,Campus Universitario Morro Do Cruzeiro | Tenorio J.A.S.,University of Sao Paulo | Jannotti N.,Jr. | Araujo F.G.D.S.,Federal University of Ouro Preto
International Journal of Mineral Processing | Year: 2015

Manganese lump ores are still the main raw material used in the manufacture of manganese ferroalloys, but the processing of the ore to the beneficiation point generates fines. So an alternative to be studied is making pellets. This work compares the main geometallurgical characteristics of the lump ore from the Azul Mine and the pellets made from fines generated during beneficiation of this lump ore on a small scale. The characteristics assessed were: the chemical composition, mineralogical constitution, hot and cold particle disintegration, thermal decomposition and solid state reduction. It can be observed that the pellets contain a greater proportion of manganese oxides than the lump ore and they are also richer in Mn. In the pellets the hot and cold particle disintegration phenomena are minimal when compared with those found in lump ore. Lump ore can be efficiently reduced in the solid state, while most of the manganese minerals in the pellets have already been reduced to MnO. The conclusion is that manufacturing pellets in order to take advantage of the manganese ore fines is a path that must be studied further, since the pellets can be used as a viable source of manganese and act as agents that contribute to the increase in permeability of the charge. But possible reductions in the temperature of the granular zone during solid state reduction need to be considered. © 2015 Elsevier B.V. All rights reserved. Source


Barancelli D.A.,University of Campinas | Salles A.G.,University of Campinas | Taylor J.G.,Campus Universitario Morro Do Cruzeiro | Correia C.R.D.,University of Campinas
Organic Letters | Year: 2012

Free ortho-hydroxy cinnamate ester derivatives are evaluated in the synthesis of structurally diverse 4-aryl-coumarins via a tandem Heck-Matsuda cyclization reaction. Free phenolic groups were considered incompatible with such a reaction, which usually provide the corresponding diazo dyes. A concise and scalable route employing a ligand-free, Pd-catalyzed Heck-Matsuda arylation under aerobic conditions for the preparation of (R)-Tolterodine in high overall yield and ee is also presented. © 2012 American Chemical Society. Source


Faria G.L.,Campus Universitario Morro Do Cruzeiro | Tenorio J.A.S.,University of Sao Paulo | Jannotti Jr. N.,VALE Manganes | Da S. Araujo F.G.,Federal University of Ouro Preto
International Journal of Mineral Processing | Year: 2013

This pioneering study characterized the chemical, physical and mineralogical aspects of the Urucum Standard manganese ore typology, and evaluated some of its metallurgical characteristics, such as the main mineral heat decompositions, and the particle disintegration at room temperature and under continuous heating. A one-ton sample of ore was received, homogenized and quartered. Representative samples were collected and characterized with the aid of techniques, such as ICP-AES, XRD, SEM-EDS, BET and OM. Representative samples with particle sizes between 9.5 mm and 15.9 mm were separated to perform tumbling tests at room temperature, and thermogravimetry tests for both air and nitrogen constant flow at different temperatures. After each heating cycle, the mechanical strength of the ore was evaluated by means of screening and tumbling procedures. The Urucum Standard typology was classified as an oxidized anhydrous ore, with a high manganese content (∼ 47%). This typology is mainly composed of cryptomelane and pyrolusite; however there is a significant amount of hematite. The Urucum Standard particles presented low susceptibility to disintegration at room temperature, but as temperature increased, susceptibility increased. No significant differences were observed between the tests done with the air or nitrogen injections. © 2013 Elsevier B.V. Source


Paro M.D.O.,Campus Universitario Morro Do Cruzeiro | Ferreira C.S.,Campus Universitario Morro Do Cruzeiro | Vieira F.S.,Campus Universitario Morro Do Cruzeiro | De Santana M.A.,Campus Universitario Morro Do Cruzeiro | And 4 more authors.
International Journal of Peptides | Year: 2013

Von Willebrand disease (VWD) is an inherited hemorrhagic disorder promoted by either quantitative or qualitative defects of the von Willebrand factor (VWF). The disease represents the most common human coagulopathy afflicting 1.3% of the population. Qualitative defects are subdivided into four subtypes and classified according to the molecular dysfunction of the VWF. The differential diagnosis of the VWD is a difficult task, relying on a panel of tests aimed to assess the plasma levels and function of the VWF. Here, we propose biochemical approaches for the identification of structural variants of the VWF. A bioinformatic analysis was conducted to design seven peptides among which three were representatives of specific amino acid sequences belonging to normal VWF and four encompassed sequences found in the most common VWD subtype 2B. These peptides were used to immunize mice, after which, peptide-specific immunoglobulins were purified. This resulted in four Ig preparations capable of detecting alterations in the subtype 2B VWD plus additional three antibody fractions targeting the normal VWF. The panel of antibodies could serve many applications among them (1) assessment of VWF: antigen interaction, (2) VWF multimer analysis, and (3) production of monoclonal antibodies against VWF for therapeutic purposes as in thrombotic thrombocytopenic purpura. © 2013 Marina de Oliveira Paro et al. Source


De Assis L.V.M.,Campus Universitario Morro Do Cruzeiro | De Assis L.V.M.,Federal University of Ouro Preto | Locatelli J.,Campus Universitario Morro Do Cruzeiro | Locatelli J.,Federal University of Ouro Preto | And 3 more authors.
Biochimica et Biophysica Acta - Reviews on Cancer | Year: 2014

Malignant Mesothelioma (MM) is a very aggressive cancer with low survival rates and often diagnosed at an advanced stage. Several players have been implicated in the development of this cancer, such as asbestos, erionite and the simian virus 40 (SV40). Here, we have reviewed the involvement of erionite, SV40, as well as, the role of several genes (p16INK4a, p14ARF, NF2, LATS2, SAV, CTNNB1 and among others), the pathways (RAS, PI3K, Wnt, BCL and Hippo), and their respective roles in the development of MM. © 2014 Elsevier B.V. Source

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