Environmental effects on viscoelastic behavior of carbon fiber/PEKK thermoplastic composites

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The effects of the C-terminal amidation of mastoparans on their biological actions and interactions with membrane-mimetic systems

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

Exact Solution of the Elastica with Transverse Shear Effects

A new derivation of Euler's Elastica with transverse shear effects included is presented. The elastic potential energy of bending and transverse shear is set up. The work of the axial compression force is determined. The equation of equilibrium is derived using the variation of the total potential. Using substitution of variables an exact solution is derived. The equation is transcendental and does not have a closed form solution. It is evaluated in a dimensionless form by using a numerical procedure. Finally, numerical examples of laminates made of composite material (fiber reinforced) and sandwich panels are provided.

Effects of railway track vibration induced by passing trains on an energy harvesting device

Pós-graduação em Engenharia Mecânica - FEIS

Assessment of structural cardiac abnormalities and diastolic function in women with gestational diabetes mellitus

Background: The main manifestation of hyperglycaemia during pregnancy is gestational diabetes mellitus. It can herald diabetes mellitus type 2 and its deleterious long-term effects, such as hypertension and cardiovascular disease. The aim of this study was to assess diastolic function in women with gestational diabetes mellitus, one of the first signs of future cardiovascular disease.Methods: A total of 21 women with gestational diabetes mellitus and 23 healthy pregnant women (control group) between 34 and 37weeks of gestation underwent echocardiographic assessment. The diagnosis of gestational diabetes mellitus was made in agreement with the American Diabetes Association criteria. Echocardiographic images obtained were analysed according to the criteria of the American Society of Echocardiography. Data were analysed using Pearson correlation coefficient, analysis of variance and Student's t-test.Results: Women with gestational diabetes mellitus had higher posterior wall and interventricular septum thickness, increased left ventricular mass and left ventricular mass index, lower early diastolic annular velocity and early diastolic annular velocity/late diastolic annular velocity ratio. There was a positive correlation between left ventricular mass index and fasting glucose and pregnancy body mass index.Conclusion: Patients with gestational diabetes mellitus seem to have a different diastolic profile as well as a mildly dysfunctional pattern on echocardiogram, which may show a need for greater glycaemic control.

Effects of andiroba (Carapa guianensis) oil in ticks: ultrastructural analysis of the synganglion of Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae)

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

Effect of ion irradiation on the structural properties and hardness of a-C:H:Si:O:F films

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

Characterization of Soil Surface Roughness Effects on Runoff and Soil Erosion Rates under Simulated Rainfall

This study aims at identifying the influence of soil surface roughness from small to large aggregates (random roughness) on runoff and soil loss and to investigate the interaction with soil surface seal formation. Bulk samples of a silty clay loam soil were sieved to four aggregate-size classes of 3 to 12, 12 to 20, 20 to 45, 45 to 100 mm, and packed in soil trays set at a 5% slope. Rainfall simulations using an oscillating nozzle simulator were conducted for 90 min at an average rainfall intensity of 50.2 mm h(-1). Soil surface roughness was measured using an instantaneous profile laser scanner and surface sealing was studied by macroscopic analysis of epoxy impregnated soil samples. The rainfall simulations revealed longer times to initiate runoff with increasing soil surface roughness. For random roughness levels up to 6 mm, a decrease in final runoff rate with increasing roughness was observed. This can be attributed to a decreased breakdown of the larger roughness elements on rougher surfaces, thus keeping infiltration rate high. For a random roughness larger than 6 mm, a greater final runoff rate was observed. This was caused by the creation of a thick depositional seal in the concentrated flow areas, thus lowering the infiltration rates. Analysis of impregnated soil sample blocks confirmed the formation of a structural surface seal on smooth surfaces, whereas thick depositional seals were visible in the depressional areas of rougher surfaces. Therefore, from our observations it can be learned that soil surface roughness as formed by the presence of different aggregate sizes reduces runoff but that its effect diminishes due to aggregate breakdown and the formation of thick depositional seals in the case of rough soil surfaces. Sediment concentration increased with increasing soil surface roughness, due to runoff concentration in flow paths. Nevertheless, final soil loss rates were comparable for all soil roughness categories, indicating that random roughness is only important in influencing runoff rates and the time to initiate runoff, but not in influencing sediment export through soil loss rates.

Effects of time exposure and low power sonochemical treatment on ZnO mesostructures

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

The effects of land use and soil management on the physical properties of an Oxisol in Southeast Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effects of chronic fluoride intake on the antioxidant systems of the liver and kidney in rats

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

An investigation into the effects of resonances on the time delay estimate for leak detection in buried plastic water distribution pipes

In water distribution systems, old metallic pipes have been replaced by plastic pipes due to their deterioration over time. Although acoustic methods are effective in finding leaks in metallic pipes, they have been found to be problematic when applied to plastic pipes due to the high damping within the pipe wall and the surrounding medium. This is responsible for the leak signal not traveling long distances. Moreover, the leak energy in plastic pipes is generally located at a narrow frequency range located at low frequencies. However, the presence of resonances can narrow even more this frequency range. In order to minimise the influence of background noise and resonances on the calculation of the time delay estimate, band-pass filters are often used to supress undesirable frequency components of the noise. The objective of this paper is to investigate the influence of resonances in the pipe system (pipe, valves, connections and hydrants), on the time delay estimate calculated using acoustic signals. Analytical models and actual leak data collected in a bespoke rig located in the United Kingdom are used to investigate this feature.

Ayahuasca alters structural parameters of the rat aorta

Ayahuasca is a hallucinogenic brew traditionally used by Northwestern Amazonian indigenous groups for therapeutic purposes. It is prepared by the decoction of Banisteriopsis caapi with the leaves of Psychotria viridis. Banisteriopsis caapi contains β-carbolines that are inhibitors of monoamine oxidase and P. viris is rich in dimethyltryptamine, a 5-HT(1A/2A/2C) agonist. Acute ayahuasca administration produces moderate cardiovascular effects in healthy volunteers, but information regarding long-term use is lacking. This study investigated the effects of ayahuasca (2-4 mL/kg) in the rat aorta after acute and chronic (14 days) administration. Ayahuasca caused flattening and stretching of vascular smooth muscle cells and changes in the arrangement and distribution of collagen and elastic fibers. Chronic treatment with the higher dose significantly increased media thickness and the ratio of media thickness to lumen diameter. More research is needed on the cardiovascular function of long-term ayahuasca consumers.

Structural and functional evidence for membrane docking and disruption sites on phospholipase A2-like proteins revealed by complexation with the inhibitor suramin

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

Protective effects of the galectin-1 protein on in vivo and in vitro models of ocular inflammation

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