173 resultados para TENORIO, OTILINIO


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The deep-water molluscs collected during the expedition MD55 off SE Brazil have been gradually studied in some previous papers. The present one is focused on samples belonging to caenogastropod taxa Xenophoridae Troschel, 1852, Cypraeoidea Rafinesque, 1815, mitriforms and Terebridae Morch, 1852. Regarding the Xenophoridae, Onustus aquitanus n. sp. is a new species, collected off the littoral of Espirito Santo and Rio de Janeiro, Brazil, 430-637 m depth (continental slope). The main characters of the species include the small size (c. 20 mm), the proportionally wide shell, the white colour, the short peripheral flange, the oblique riblets weakly developed and a brown multispiral protoconch. This appears to be the smallest living species of the family, resembling in this aspect fossil species. In respect to the Cypraeoidea, the following results were obtained: family Cypraeidae Rafinesque, 1815: Erosaria acicularis (Gmelin, 1791) and Luria cinerea (Gmelin, 1791) had the deepest record, respectively 607-620 m and 295-940 m, although the samples were all dead, eroded shells. Family Lamellariidae d'Orbigny, 1841: a total of three lots were collected, provisionally identified as Lamellaria spp. as the samples consist of only vestigial shells; possibly each lot represents a different species. Family Pediculariidae Gray, 1853: a sample of Pedicularia tibia Simone, 2005 was found, expanding the range c. 1000 km southwards, from Ceara to Espirito Santo. Family Ovulidae Fleming, 1822: Pseudosimnia lacrima n. sp., collected off Espirito Santo, 607-620 m depth, is described here and is mainly characterised by its strong biconic outline, small size (c. 7 mm), and a thick peripheral callus. Family Triviidae Troschel, 1863: Cleotrivia antillarum (Schilder, 1922) is recorded for the first time as deep as 620 m, and its distribution expanded from Rio Grande do Norte to Espirito Santo; Dolichupis akangus n. sp. with rounded outline and c. 15 transverse ribs; D. pingius n. sp. with the outer lip expanded posteriorly and c. 10 ribs. In respect to the mitriform neogastropods, the following species are emphasised: family Costellariidae MacDonald, 1860: Vexillum sp., 607-620 m depth; Turricostellaria amphissa n. sp., 295 m depth; T. jukyry n. sp.; T. apyrahi n. sp., both 790-1575 m depth; T. ovir n. sp., 1200 m depth; Nodicostellaria crassa (Simone, 1995), 240-600 m depth, with extension northwards of the range up to Espirito Santo; Austromitra decresca n. sp., 60-105 m depth. Family Mitridae Swainson, 1829: Subcancilla joapyra n. sp., 295 m depth; S. cf. straminea (Adams, 1853), 607-620 m depth. Family Volutomitridae Gray, 1854: Microvoluta corona n. sp., 1500-1575 m depth. Family Mitromorphidae Casey, 1904: Mitromorpha sama n. sp., 607-940 m depth; M. mirim n. sp., 60105 m depth. Regarding the conoidean Terebridae, this paper is a complement of a previous study. It deals with a new species Terebra assu Simone n. sp., from the Abrolhos Bank, 295 m depth, characterised by its narrow outline, yellowish colour, weak sculpture on the last whorls, and a proportionally broad, paucispiral protoconch. A second finding of Terebra alagoensis Lima, Tenorio & Barros, 2007 expands the geographic range from Alagoas to north Espirito Santo. A discussion on the systematics of the "complex Terebra doellojuradoi" in South American coast is also provided, highlighting the improbability of synonymy between T. leptapsis Simone, 1999 and T doellojuradoi Carcelles, 1953. Differences in size, sculpture, spire angulation, aperture, and mainly in protoconch, indicate specific separations. The presently studied terebrids belong to the "complex Terebra doellojuradoi", which encompasses closely related, deep-water, small species, possessing a relatively high degree of endemicity.

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The world's largest ethanol producer (USA) uses corn as feedstock. DDGS (distillers dried grains with solubles) is the main waste generated from this process (around 32 million t/year). DDGS samples were pyrolyzed at 1000 ºC in a furnace with controlled atmosphere. The effluent was channeled to a second furnace, in which catalyst substrates were placed. Chromatographic analysis was used to evaluate the gaseous effluents, showing that the catalyst reduced hydrocarbon emissions. The solid products formed were analyzed by SEM and TEM. Graphitic structures and carbon nanofibers, 50 µm in length and with diameters of 80-200 nm, were formed.

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As fibras cerâmicas se caracterizam por ser um material leve, com alto grau de pureza, baixo armazenamento de calor, baixa condutividade térmica, resistência a choque térmico e alta resistência à corrosão em altas temperaturas. Essas características levam a uma grande procura das indústrias mínero-metalúrgicas e de outros setores para revestimentos de distribuidores, muflas, fornos de aquecimentos, entre outros. Após utilização no processo, por perderem sua capacidade de isolamento, os resíduos gerados precisam de destinação. Esse trabalho enfoca, especificamente, resíduos de lã cerâmica e lã de vidro. Pelo fato de a composição das fibras cerâmicas ser rica em sílica e alumina, efetuou-se uma investigação acerca da atividade pozolânica das mesmas com a cal e o cimento, especificamente CPV ARI, CPII E32 e CPIII 32RS, para avaliação da perspectiva de reciclagem em possível incorporação no concreto.

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The objective of this paper is to present an analysis of the use of residual marble mixtures in the pig iron desulfurization process. The study involved the use of: marble waste, fluorspar, lime, and hot metal. Four mixtures were made and added to a liquid hot metal - with known chemical composition - at a temperature of 1450ºC. The mass of each element was calculated from its chemical analysis and compared with an industrial mixture. All of the four mixtures used in the experiments were stirred by a mechanical stirrer. Samples were collected by vacuum sampling for times of 5, 10, 15, 20, and 30 minutes, and analysis was performed to check sulfur variation in the bath with time. The results were analyzed and they verified that it was possible to use marble waste as a desulfurizer.

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Esse trabalho estuda a viabilidade técnica da fabricação de cimento com uma mistura de resíduo proveniente da serragem de blocos de granito e escória de aciaria LD. Para isso, foi preparada uma mistura desses materiais de modo que a relação %CaO / %SiO2 fosse 1,2. Essa mistura foi fundida e resfriada rapidamente em água. A amostra foi caracterizada e o difratograma de raios X mostrou um material amorfo e a presença das fases mineralógicas Akermanita e Gehlenita, as quais são consideradas como as fases mineralógicas ideais para a atividade hidráulica. Essa mistura foi adicionada ao clínquer para a fabricação de cimento. Com o cimento fabricado, foram feitos ensaios cujos resultados são apresentados e comparados com os valores obtidos para o cimento de alto-forno. Esses resultados indicam a viabilidade técnica da utilização da mistura na fabricação de cimento.

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Esse trabalho consiste na caracterização do resíduo de mármore, lama fina de aciaria e borra de alumínio, para averiguar a viabilidade técnica da utilização de tais resíduos na dessulfuração e desfosforação de ferro-gusa líquido. A caracterização desses resíduos foi feita através de análises químicas, granulométricas, difração de raios X e microscopia eletrônica de varredura (MEV) com micro análise por Espectroscopia por Energia Dispersiva de Raios X (EDS). A lama fina de aciaria apresenta um teor de FeO de 84,90%, o resíduo de mármore apresentou um teor de 61,5% de CaO e 33,9% de MgO e a borra de alumínio apresentou 36,5% de Al metálico e 62% de Al2O3. A granulometria do resíduo de mármore apresentou um tamanho de grão médio igual 42,810 µm. Já, na borra de alumínio, o tamanho médio foi de 101,803 µm. A lama fina de aciaria LD apresentou, em torno de 54,7% de sua granulometria, entre 0,15 e 0,075mm. Esses resultados apontam para a viabilidade técnica da utilização desses materiais na dessulfuração e desfosforação do ferro-gusa.

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O objetivo da pesquisa é recuperar os principais metais presentes em um lote com uma mistura de diversos tipos de pilhas e de baterias descartadas após o uso, lote obtido em um posto de coleta. Para esse estudo, o resíduo das pilhas e das baterias foi moído, reduzido em forno elétrico, submetido à separação magnética e lixiviado. A composição química, após a lixiviação, foi reproduzida em uma solução sintética, que foi submetida à extração por solventes e reextração sendo que as soluções obtidas, após as reextrações, foram utilizadas como eletrólitos. Manganês, cobre, cobalto e níquel são recuperados na forma metálica após um tratamento que inclui as etapas pirometalúrgica, hidrometalúrgica e eletroquímica. Estudos anteriores definiram os parâmetros das etapas pirometalúrgica, lixiviação e extração por solventes que proporcionaram separação mais seletiva dos íons metálicos que se pretende recuperar. A contribuição do presente estudo é encontrar um processo que trate de todos os tipos de pilhas e de baterias juntos e recuperar seus metais mais importantes, evitando, assim, a etapa de separação prévia das baterias. Os filmes foram analisados quanto à sua espessura e composição.

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In this study, transplacental transmission of Neospora caninum in bitches at different stages of pregnancy was evaluated. Three bitches were inoculated in the 3rd week and three in the 6th week of gestation with 10(8) tachyzoites of N. caninum (Nc-1 strain). All the infected bitches and at least one of their offspring presented anti-N. caninum antibodies according to the indirect fluorescent antibody test (IFAT > 400). The pups and their mothers were sacrificed and tissues from the central nervous system (CNS), popliteal lymph nodes, skeletal muscle, brain, lungs, heart and liver were analyzed for the presence of N. caninum using the nested polymerase chain reaction (nested PCR), restriction fragment length polymorphism (RFLP) and immunohistochemistry (IHC). The parasite was found in the pups in lymph node, CNS, heart and liver tissues using nested PCR. There was no difference in perinatal mortality between the offspring from bitches infected in the 3rd week of gestation (60%) and in the 6th week (53.8%).

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This work addresses the treatment of lower density regions of structures undergoing large deformations during the design process by the topology optimization method (TOM) based on the finite element method. During the design process the nonlinear elastic behavior of the structure is based on exact kinematics. The material model applied in the TOM is based on the solid isotropic microstructure with penalization approach. No void elements are deleted and all internal forces of the nodes surrounding the void elements are considered during the nonlinear equilibrium solution. The distribution of design variables is solved through the method of moving asymptotes, in which the sensitivity of the objective function is obtained directly. In addition, a continuation function and a nonlinear projection function are invoked to obtain a checkerboard free and mesh independent design. 2D examples with both plane strain and plane stress conditions hypothesis are presented and compared. The problem of instability is overcome by adopting a polyconvex constitutive model in conjunction with a suggested relaxation function to stabilize the excessive distorted elements. The exact tangent stiffness matrix is used. The optimal topology results are compared to the results obtained by using the classical Saint Venant–Kirchhoff constitutive law, and strong differences are found.

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We have previously shown the differential expression of versican in the mouse uterus under ovarian hormone influence. We also demonstrated there is not a direct correlation between mRNA levels and protein expression, suggesting posttranscriptional events, such as alteration in mRNA stability. This posttranscriptional effect may result in the elongation and stabilization of transcripts poly(A) tail. Thus, the aim of this study was to analyze whether estradiol (E2) regulates versican mRNA stability and expression in a dose-related and time-dependent manner. For this purpose female mice were ovariectomized and treated with a single injection of 0.1 or 10 μg E2. To block transcription a group of females received a single injection of alpha-amanitin before hormone administration. Uterine tissues were collected 30 min, 1, 3, 6, 12 and 24 h after treatments and processed for quantitative real time PCR (qPCR), RACE-PAT Assay and immunohistochemistry. qPCR showed that versican mRNA levels are higher than control from 3 to 24 h after E2 administration, whereas after transcription inhibition versican mRNA unexpectedly increases within 3 h, which can be explained when transcriptional blockers alter the degradation rate of the transcript, resulting in the superinduction of this mRNA. Accordingly, analysis of versican transcript poly(A) tail evidenced a longer product 3 h after treatment, but not after 12 h. Versican immunoreaction becomes conspicuous in the superficial stroma only 3 h after E2 injection, whereas the whole stroma is immunoreactive from 6 h onward. These results demonstrate that E2 modulates versican at the transcriptional and posttranscriptional levels in a time-dependent manner.

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Signal transducers and activators of transcription 3 (STAT3) has been identified as an important signal transducer in the invasive phenotype of the trophoblasts cells in in vitro studies. However, the in situ distribution and patterns of expression of this molecule in trophoblast cells during the development of the placenta are still under-elucidated. Mice uteri of gestational ages between 7 and 14 days of pregnancy (dop) were fixed in methacarn and processed with immunoperoxidase techniques for detection of STAT3 and its phosphorylation at serine (p-ser727) residues, as well as the suppressor of cytokine signaling 3 (SOCS3) expression. STAT3 was observed at 7 through 9 dop in both the antimesometrial and mesometrial deciduas, while continued immunoreactivity between 10 and 13 dop was seen only in the mesometrial decidua. In the placenta, STAT3 was detected in the cytotrophoblast cells of labyrinth and giant trophoblast cells between 10 and 14 dop. Immunoreactivity for STAT3 was also seen in trophoblast cells surrounding the maternal blood vessels. On days 10 and 11 of pregnancy, p-ser727 was detectable in the mesometrial decidua and in giant trophoblasts, while during 12-14 dop in the spongiotrophoblast region. In addition, SOCS3 was immunodetected in maternal and placental tissues, principally in the giant trophoblast cells during the whole period of the study. The present in situ study shows the distribution of STAT3, its serine activation and SOCS3 in different maternal and fetal compartments during murine placental development, thus further supporting the idea that they play a role during physiological placentation in mice.

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Introduction: Endometrial decidualization and associated extracellular matrix (ECM) remodeling are critical events to the establishment of the maternal-fetal interface and successful pregnancy. Here, we investigated the impact of type 1 diabetes on these processes during early embryonic development, in order to contribute to the understanding of the maternal factors associated to diabetic embryopathies. Methods: Alloxan-induced diabetic Swiss female mice were bred after different periods of time to determine the effects of diabetes progression on the development of gestational complications. Furthermore, the analyses focused on decidual development as well as mRNA expression, protein deposition and ultrastructural organization of decidual ECM. Results: Decreased number of implantation sites and decidual dimensions were observed in the group mated 90-110 days after diabetes induction (D), but not in the 50-70D group. Picrosirius staining showed augmentation in the fibrillar collagen network in the 90e110D group and, following immunohistochemical examination, that this was associated with increase in types I and V collagens and decrease in type III collagen and collagen-associated proteoglycans biglycan and lumican. qPCR, however, demonstrated that only type I collagen mRNA levels were increased in the diabetic group. Alterations in the molecular ratio among distinct collagen types and proteoglycans were associated with abnormal collagen fibrillogenesis, analyzed by transmission electron microscopy. Conclusions: Our results support the concept that the development of pregnancy complications is directly related with duration of diabetes (progression of the disease), and that this is a consequence of both systemic factors (i.e. disturbed maternal endocrine-metabolic profile) and uterine factors, including impaired decidualization and ECM remodeling

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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 orewas 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 ismainly composed of cryptomelane and pyrolusite; however there is a significantamount 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.

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Five Mycoplasma strains from wild Caprinae were analyzed: four from Alpine ibex (Capra ibex) which died at the Berlin Zoo between 1993 and 1994, one from a Rocky Mountain goat collected in the USA prior to 1987. These five strains represented a population different from the populations belonging to the 'Mycoplasma mycoides cluster' as tested using multi locus sequence typing, Matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis and DNA-DNA hybridization. Analysis of the 16S rRNA gene (rrs), genomic sequence based in silico as well as laboratory DNA-DNA hybridization, and the analysis of phenotypic traits in particular their exceptionally rapid growth all confirmed that they do not belong to any Mycoplasma species described to date. We therefore suggest these strains represent a novel species, for which we propose the name Mycoplasma feriruminatoris sp. nov. The type strain is G5847(T) (=DSM 26019(T)=NCTC 1362(T)).

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AIMS:During β-adrenergic receptor (β-AR) stimulation, phosphorylation of cardiomyocyte ryanodine receptors by protein kinases may contribute to an increased diastolic Ca(2+) spark frequency. Regardless of prompt activation of protein kinase A during β-AR stimulation, this appears to rely more on activation of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII), by a not yet identified signalling pathway. The goal of the present study was to identify and characterize the mechanisms which lead to CaMKII activation and elevated Ca(2+) spark frequencies during β-AR stimulation in single cardiomyocytes in diastolic conditions. METHODS AND RESULTS:Confocal imaging revealed that β-AR stimulation increases endogenous NO production in cardiomyocytes, resulting in NO-dependent activation of CaMKII and a subsequent increase in diastolic Ca(2+) spark frequency. These changes of spark frequency could be mimicked by exposure to the NO donor GSNO and were sensitive to the CaMKII inhibitors KN-93 and AIP. In vitro, CaMKII became nitrosated and its activity remained increased independent of Ca(2+) in the presence of GSNO, as assessed with biochemical assays. CONCLUSIONS:β-AR stimulation of cardiomyocytes may activate CaMKII by a novel direct pathway involving NO, without requiring Ca(2+) transients. This crosstalk between two established signalling pathways may contribute to arrhythmogenic diastolic Ca(2+) release and Ca(2+) waves during adrenergic stress, particularly in combination with cardiac diseases. In addition, NO-dependent activation of CaMKII is likely to have repercussions in many cellular signalling systems and cell types.