Caracterização microestrutural de uma estrutura tubular aeronáutica submetida a sucessivos reparos de solda TIG

This work examines the possible effects of successive repair procedures on the microstructure of welded steel SAE 4130 by TIG welding process. Discussions and results were made about the metallographic analysis , non-metallic inclusions and microhardness tests , which were conducted on samples taken from the cradle engine component after the end of its life , a model airplane T-27 Tucano , made by EMBRAER and belonging were performed FAB . The choice of such component is due to the fact that this is critical to flight safety since it provides support for the aircraft engine . Thus regions of the weld metal , base metal and heat affected , with samples of the original weld bead , free of weld bead and also with four rework procedures for TIG welding zone were analyzed . It was found that after the fourth rework there is an increase in the amount of martensite , which may weaken the material with respect to resistance to fatigue. It was also found that the regions of the heat affected zone and weld metal have higher microhardness values when compared to those found in the base metal due to favoring the formation of ferritic and tempered martensite microstructures . Moreover, a welding process promotes a region with less non-metallic inclusions than metal base , which also explains the difference in the results obtained

Androecia in two Clusia species: development, structure and resin secretion

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structure and secretion mechanisms of floral glands in Diplopterys pubipetala (Malpighiaceae), a neotropical species

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Leaf colleters in Tabernaemontana catharinensis (Apocynaceae, Rauvolfioideae): structure, ontogenesis, and cellular secretion

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Distribution of non-LEE-encoded type 3 secretion system dependent effectors in enteropathogenic Escherichia coli

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ultrastructure of the parotid and submandibular glands of the Old World marten (Carnivora; Mustelidae)

The morphology of the parotid and submandibular glands in the marten, a carnivore, were studied and analyzed under a transmission electron microscope. The nature of the granules in both glands, as well as in the acini and in the secretory tubules, is rather mucous. The structure of the secretory tubules is very characteristic, especially the striated ones. The myoepithelial cells are close to the acini and tubules and covered by the basement membrane separating them from the connective tissue, which enhances its epithelial origin. The cytoplasm of the basal parts of the acinar and tubular cells is abundant and separates the nucleus from the secretion granules. Although the morphology of the salivary glands of many carnivores is known, those of the parotid gland of the marten present peculiar characteristics, since they produce a rather mucous saliva and the granules, when forming, are far from the base as well as from the apex of the secretory cells. The submandibular gland contains granules of different densities, an aspect that in general resembles that of other animals.

Type IV secretion system is not involved in infection process in citrus

The type IV secretion system (T4SS) is used by Gram-negative bacteria to translocate protein and DNA substrates across the cell envelope and into target cells. Xanthomonas citri subsp. citri contains two copies of the T4SS, one in the chromosome and the other is plasmid-encoded. To understand the conditions that induce expression of the T4SS in Xcc, we analyzed, in vitro and in planta, the expression of 18 ORFs from the T4SS and 7 hypothetical flanking genes by RT-qPCR. As a positive control, we also evaluated the expression of 29 ORFs from the type III secretion system (T3SS), since these genes are known to be expressed during plant infection condition, but not necessarily in standard culture medium. From the 29 T3SS genes analyzed by qPCR, only hrpA was downregulated at 72 h after inoculation. All genes associated with the T4SS were downregulated on Citrus leaves 72 h after inoculation. Our results showed that unlike the T3SS, the T4SS is not induced during the infection process.

Bothropoides pauloensis venom effects on isolated perfused kidney and cultured renal tubular epithelial cells

Coordenadação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A influência das variáveis do lixamento tubular na qualidade das peças de Eucalyptus grandis

In 2010, the Brazilian forest sector is represented by about 30,000 companies producing US$ 21 billion annually and account for approximately 5% of the gross domestic product (GDP) in the country. The sanding process is highly demanded in various stages of industrialization of the wood, when there is a need for a better quality surface finishing. The objective of this work was to analyze the influence of cutting speed and sandpaper granulometry on both the surface finishing of pieces of Eucalyptus grandis processed through tubular sanding and on the sanding efforts (force and power of sanding). Four cutting speeds were used (19.5, 22.7, 26 and 28.1 m/s), one advance speed (16 m/min) and three sets of sandpaper (80-100, 80-120 and 100-120) being one for chipping and another for finishing, respectively. A central data acquisition system was set up to capture the variables (cutting power, acoustic emission and vibration) in real time. The cutting force was obtained indirectly, through a frequency inverter. The roughness of the parts was measured by a roughness meter before and after sanding. The highest cutting speed used (28.1 m/s) consumed more power and generated more acoustic emission among the four speeds tested. Regarding the vibration, the lower cutting speed (19.5 m/ s) generated the highest vibration in the sander machine. It is concluded that the range of 100-120 sandpapers resulted in values of average roughness (Ra) lower than the other sets of sandpaper used, as it resulted in better surface finishing.

Avaliação técnica e econômica de um biodigestor de fluxo tubular: estudo de caso do modelo implantado na etec "orlando quagliato" em Santa Cruz do Rio Pardo, SP

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Morfologia e desenvolvimento do sistema reprodutor masculino de carrapatos do gênero Amblyomma (Acari, Ixodidae): uma análise comparativa

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morfologia e desenvolvimento do sistema reprodutor masculino de carrapatos do gênero Amblyomma (Acari, Ixodidae): uma análise comparativa

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

An inhibitor of leukotriene synthesis affects vasopressin secretion following osmotic stimulus in rats

Previous studies revealed the presence of LTC4 synthase in paraventricular vasopressinergic neurons, suggesting a role for leukotrienes (LTs) in certain neuroendocrine system functions. Our aim was to study the effect of an inhibitor of LT synthesis in the release of arginine vasopressin (AVP) following an osmotic stimulus in rats. Male Wistar rats received an intra-cerebroventricular injection of 2 mu l of the LT synthesis inhibitor MK-886 (1, 2, or 4 mu g/kg), or vehicle (DMSO 5%), 1 h before an intraperitoneal injection of hypertonic saline (NaCl 2 M) or isotonic saline (NaCl 0.01 M) in a volume corresponding to 1% of body weight. Thirty minutes after the osmotic stimulus, the animals were decapitated and blood was collected for determining hematocrit, plasma osmolality and plasma AVP levels. As expected, the injection of hypertonic saline significantly increased (P<0.05) the hematocrit, plasma osmolality and plasma AVP levels. While inhibiting LT synthesis by central administration of MK-886 did not cause any additional increase in hematocrit or osmolality, plasma AVP levels were augmented (P<0.05). We conclude that central leukotrienes may have a modulatory role in AVP secretion following an osmotic stimulus, this deserving future studies. (C) 2012 Elsevier B.V. All rights reserved.