Lixamento do Pinus elliotti com carbeto de silício e óxido de aluminio

The Sanding is a complex process involving many variables that affect the quality of the part produced, working mainly in the timber industry in the production of panels (MDF, MDP, HDF, etc...) and furniture. However, these industries use the sanding process empirically, not optimizing it. The aim of this study was to compare the behavior of sandpaper white aluminum oxide (OA-white) and Black silicon carbide (SiC-black), analyzing variables in the process as: strength, power, emission, vibration, wear particle size of sanding, and its consequences on the surface finish of the workpiece. Made the process of plane grinding samples of Pinus elliottii, processed in parallel to the fibers, which were sanded with sandpaper grain OA white and black 3-SiC abrasive conditions (new, moderately eroded and severely eroded) grain sizes in 3 (80, 100, and 120 mesh). 6 replicates was performed for each condition tested. Each trial was captured output variables of the sanding process: strength, power, emission and vibration. With two stages totaling 108 trials. After the sanded samples, it has the same surface quality by raising the surface roughness Ra. Through experiment, it can be concluded that abrasives OA-white tended to have higher strength, power, emissions and less vibration in the sanding process, compared to the SiC-black. However, surface finish exhibited similar to the particle size of 80 to 100 mesh, worn abrasive conditions. However, the particle size of 120 mesh, obtained by the roughness of sandpaper OA-bank was higher compared to SiC-black to all conditions of sandpaper due to its toughness

Caracterização morfológica e fenotípica de leveduras do gênero Cryptococcus com ênfase na pesquisa de Cryptococcus neoormans isoladas de amostras de água de mar e areia de três ambientes costeiros do estado de São Paulo: Canal de São Sebastião, Baixada Santista e Ubatuba

The yeast Cryptococcus neoformans is the etiologic agent of cryptococcosis, an infectious cosmopolitan disease that affects humans. Although rare, this disease is potentially fatal, especially for immunocompromised hosts. This pathogen is frequently isolated from excrements of pigeons and parrots, with many environmental sources such as birds, pigeon droppings, eucalyptus leaves, decaying trees, towers, churches and places of storage of grain (the port area). The isolation of this microorganism has been obtained also from the aquatic environment. The identification of environmental sources is needed to protect human health, especially susceptible populations such as immunocompromised. Therefore, this study investigated the presence of Cryptococcus neoformans in yeast isolates obtained from samples of sea water and sand from three regions of São Paulo: São Sebastião Channel, Santos and Ubatuba. Isolates were analyzed according to micro-and macroscopic characteristics and biochemical tests: microculture, urease, ink nankin, auxanograma, zymogram and phenol. We analyzed 199 isolates, 175 of which had features suggestive for Cryptococcus spp. in microculture. All these 175 isolates were sown in the Christensen urea middle to verify the production of urease and submitted to the technique nankin ink to visualize the capsule. Of these, only 24 were selected for the next test that was the auxanograma (assimilation of carbohydrate and nitrogen). Of the 24, 10 were tested in zymograms (fermented sugar), from which 5 were selected for the phenoloxidase test in medium containing dopamine. None of the 5 isolates tested had black or brown color characteristic of Cryptococcus neoformans. According to these tests, we arrived at 5 isolates identified to the genus Cryptococcus, but not the neoformans specie

Sistema adesivo universal: influência da técnica de condicionamento e da pressão pulpar com soro fetal bovino ou água deionizada na resistência de união à dentina humana

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A influência do tamanho de grão ferrítico da peça na integridade superficial de peças erodidas

Pós-graduação em Engenharia Mecânica - FEIS

Longitudinal evaluation of bond strength to enamel of dental adhesive systems associated with Nd:YAG laser

Objectives: This study evaluated the durability of bond strength to enamel using total-etch (Single Bond/SB) and self-etch (Clearfil SE Bond/CSEB) adhesives associated with neody-mium: yttrium-aluminu- garnet (Nd:YAG) laser irradiation through the uncured adhesives.Methods: Bovine incisors were worn to expose an area of enamel and were divided into four groups: group 1 (control) SB + polymerization; group 2 (control) CSEB + polymerization; group 3 (laser) - B + Nd:YAG laser (174.16 J/cm(2)) + polymerization; and group 4 (laser) CSEB + Nd:YAG (174.16 J/cm(2)) + polymerization. Blocks of composite were fabricated and stored for 24 hours or 12 months, sectioned into beams, and submitted to microtensile tests. Results were analyzed by three-way analysis of variance (ANOVA) (adhesive, technique, and storage time) and Tukey tests.Results: ANOVA revealed significant differences for adhesive 3 technique and technique 3 storage time (p<0.05). The mean values (MPa) for interaction adhesive x technique (standard deviation) were as follows: SB/control = 35.78 (6.04)a; SB/laser = 26.40 (7.25)b, CSEB/control = 26.32 (5.71)b, CSEB/laser = 23.90 (7.49)b. For interaction technique x storage time the mean values were as follows: control/24 hours = 32.58 (6.49)a; control/12 months = 29.52 (8.38)a; laser/24 hours = 29.37 (5.71)a; laser/12 months = 20.92 (6.5)b. Groups with the same letters showed no statistically significant differences.Conclusion: Scanning electron microscope analysis showed evident areas of micromorphological alterations in lased samples after 12 months of water storage. Nd: YAG laser irradiation of enamel through unpolymerized totaletch adhesive significantly reduced bond strength compared with the control. Bond strength decreased when enamel samples irradiated with Nd: YAG laser through unpolymerized adhesives were stored in water for 12 months.

Medium density particleboard reinforced with bamboo laminas

The objective of this work was to evaluate the effect of the addition of bamboo laminas of the species Dendrocalamus giganteus to three-layer medium density particleboard (MDP). These laminas were glued onto both the top and the bottom of each panel. With the manufactured panels laminated with bamboo, mechanical tests based on the Brazilian Standard ABNT NBR 14810 were carried out to determine the modulus of rupture (MOR) in static bending and the tensile strength parallel-to-surface. These mechanical tests were realized in particleboards of eucalyptus and in reinforced particleboard, both produced in the laboratory. The modulus of rupture and tensile strength parallel-to-surface of the laminated MDP had values close to those that have been reported. The reinforcements increased the values of these studied properties. Nevertheless, this fact indicated the possibility to produce a stronger MDP using bamboo lamina as surface layers. These results show the possibility of using coatedbamboo MDP for utilization in large spans, for example, in flooring for mezzanines with finish on both sides, and for robust furniture as bookshelves, beds, tables, etc.

Development and test of resistive superconducting fault current limiter; acting time and its recovery conditions

Resistive-type of superconducting fault current limiters (RSFCL) have been developed for medium voltage class aiming to operate at 1 MVA power capacity and short time recovery (< 2 s). A RSFCL in form of superconducting modular device was designed and constructed using 50 m-length of YBCO coated conductor tapes for operation under 1 kV / 1 kA and acting time of 0.1 s. In order to increase the acting time the RSFCL was combined with an air-core reactor in parallel to increase the fault limiting time up to 1 s. The tests determined the electrical and thermal characteristics of the combined resistive/ inductive protection unit. The combined fault current limiter reached a limiting current of 583 A, corresponding to a limiting factor of 3.3 times within an acting time of up to 1 s.

Qualidade da madeira de árvores de guapuruvu (schizolobium parahyba (vell.) blake) com 15 anos provenientes de área de recuperação florestal

Pós-graduação em Ciência Florestal - FCA

Análise de integridade física de barragens de terra a partir da integração do método geofísico da eletrorresistividade com ensaios geotécnicos

Pós-graduação em Geociências e Meio Ambiente - IGCE

Análise de integridade física de barragens de terra a partir da integração do método geofísico da eletrorresistividade com ensaios geotécnicos

Pós-graduação em Geociências e Meio Ambiente - IGCE

The response of the Sao Paulo Continental Shelf, Brazil, to synoptic winds

The response of the Sao Paulo Continental Shelf (SPCS) to synoptic wind forcing has been analyzed. Two different methods are used for this purpose, one based on hydrographic data, bottom topography, and geographical characteristics, and a second on analyzing currentmeter data directly and using empirical orthogonal functions. Both methods show similar results for an essentially barotropic shelf. The SPCS response in the subinertial frequency band appears to be trapped on the continental shelf. Numerical experiments have also been carried out showing results that qualitatively agree with the observations, including the velocity component parallel to the coastline.

Field and laboratory studies to assess the effects of Vertimec (R) 18EC on Daphnia similis

The present study aimed to evaluate the interactions of the pesticide Vertimec (R) 18EC in aquatic ecosystems. In this respect, soil plots were contaminated with Vertimec (R) 18EC at the concentration indicated for strawberry crops (0.125 L of solution m(-2)). After the contamination, torrential rainfall was simulated and the surface runoff was collected and transferred to mesocosm tanks in five treatments, run in triplicate: (1) control-C; (2) runoff from an uncontaminated plot-UR; (3) runoff from the plot contaminated with Vertimec (R) 18EC-CR; (4) direct application of Vertimec (R) 18EC in the water-V and (5) water samples gathered randomly to verify whether there was contamination between the mesocosms-RS. Water samples from these tanks were also submitted to ecotoxicological tests with Daphnia similis and analyses to evaluate the limnological characteristics, in five collection periods over 10 days (240 h). Physical and chemical differences were observed in the water samples, mainly related to increased turbidity, suspended solids and nutrients (nitrogen and phosphate forms). Acute toxicity was observed for the direct application treatment for the entire experimental period, and in some periods for the CR treatment (from 48 h to 168 h). The results obtained suggest that the pesticide did not fully degrade during the study period (10 days) in the direct application treatment, demonstrating that the presence of other substances in the commercial formulation contribute to the maintenance of toxicity. This represents a potential risk for aquatic ecosystems in areas adjacent to where the chemical is applied. (C) 2011 Elsevier Inc. All rights reserved.

T-3 Rapidly Increases SLC2A4 Gene Expression and GLUT4 Trafficking to the Plasma Membrane in Skeletal Muscle of Rat and Improves Glucose Homeostasis

Background: Glucose transporter 4 (GLUT4) is highly expressed in muscle and fat tissue, where triiodothyronine (T-3) induces solute carrier family 2 facilitated glucose transporter member 4 (SLC2A4) gene transcription. T-3 was also shown to rapidly increase glucose uptake in myocytes exposed to cycloheximide, indicating that it might act nongenomically to regulate GLUT4 availability. We tested this hypothesis by evaluating, in thyroidectomized rats (Tx rats), the acute and/or chronic T-3 effects on GLUT4 mRNA expression and polyadenylation, protein content, and trafficking to the plasma membrane (PM) in skeletal muscle, as well as on blood glucose disappearance rate (kITT) after insulin administration. Methods: Rats were surgically thyroidectomized and treated with T-3 (0.3 to 100 mu g/100 g body weight) from 10 minutes to 5 days, and killed thereafter. Sham-operated (SO) rats were used as controls. Total RNA was extracted from the skeletal muscles (soleus [SOL] and extensorum digitalis longus [EDL]) and subjected to Northern blotting analysis using rat GLUT4 cDNA probe. Total protein was extracted and subjected to specific centrifugations for subcellular fractionation, and PM as well as microsomal (M) fractions were subjected to Western blotting analysis, using anti-GLUT4 antiserum as a probe. GLUT4 mRNA polyadenylation was examined by a rapid amplification of cDNA ends-poly(A) test (RACE-PAT). Results: Thyroidectomy reduced skeletal muscle GLUT4 mRNA, mRNA poly(A) tail length, protein content, and trafficking to the PM, as well as the kITT. The acute T-3 treatment rapidly (30 minutes) increased all these parameters compared with Tx rats. The 5-day T-3 treatment increased GLUT4 mRNA and protein expression, and restored GLUT4 trafficking to the PM and kITT to SO values. Conclusions: The results presented here show for the first time that, in parallel to its transcriptional action on the SLC2A4 gene, T-3 exerts a rapid post-transcriptional effect on GLUT4 mRNA polyadenylation, which might increase transcript stability and translation efficiency, leading to the increased GLUT4 content and availability to skeletal muscle, as well as on GLUT4 translocation to the PM, improving the insulin sensitivity, as shown by the kITT.

Swelling tests on material from the Guabirotuba Formation, Parana, Brazil, with suction control

This paper presents the swelling behaviour of clayey materials under controlled suction imposed both by a Richards chamber and by controlling the relative humidity with concentrated saline solutions. Soil-water characteristic curves (matrix and total) were determined by the filter paper method. The materials under study belong to the Guabirotuba Formation, of Pleistocene age, in the Curitiba Basin in the state of Parana, southern Brazil. Materials under several stages of suction of 5000-40 000 kPa were subjected to swelling tests in an oedometer press. The results indicated that the greater the suction the higher the swelling pressure. However, when swelling tests were carried out with suction variation controlled by relative humidity, in which the increase in moisture was very slow, the samples showed no swelling.

Using AMS combined with mineral shape preferred orientation analysis to understand the emplacement fabrics of the Apiai gabbro-norite (Ribeira Belt, SE Brazil)

The Apiai gabbro-norite is a massive fine-grained Neoproterozoic intrusion emplaced in a core of synformal structure that deforms low-grade marine metasedimentary rocks of the Ribeira Belt of south-eastern Brazil. The lack of visible magmatic layering or any internal fabric has been a major limitation in deciding whether the emplacement occurred before or after the regional folding. To assist in the tectonic interpretations, we combine low-field anisotropy of magnetic susceptibility (AMS) and silicate shape preferred orientation (SPO) to reveal the internal structure of the mafic intrusion. Magnetic data indicate a mean susceptibility of about 10(-2) SI and a mean anisotropy degree (P) of about 1.08, essentially yielded by titanomagnetite. The magnetic and silicate foliations for P >= 1.10 are parallel to each other, while the lineations tend to scatter on the foliation plane, in agreement with the dominant oblate symmetry of the AMS and SPO ellipsoids. For lower P values, the magnetic and silicate fabrics vary from coaxial to oblique, and for P <= 1.05, their shapes and orientations can be quite distinct. The crystal size distribution (CSD) of plagioclase for P > 1.05 is log linear, in agreement with a bulk simple crystallisation history. These results combined show that for a strong SPO, corresponding to a magnetic anisotropy above 1.10, AMS is a reliable indicator of the magmatic fabric. They indicate that the Apiai gabbro-norite consists of sill-like body that was inclined gently to the north by the regional folding.