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Tasca F.A.,Santa Catarina State University | Ernani P.R.,Brazilian National Council for Scientific and Technological Development | Rogeri D.A.,UDESC | Gatiboni L.C.,Brazilian National Council for Scientific and Technological Development | Cassol P.C.,Brazilian National Council for Scientific and Technological Development
Revista Brasileira de Ciencia do Solo | Year: 2011

Ammonia volatilization is an important process of N loss which decreases the use efficiency of N by plants when urea is applied on the soil surface. To overcome this problem, some chemical compounds were mixed with urea to inhibit the urease action. The purpose of this study was to compare applications of an alternative fertilizer with urease inhibitor to reduce ammonia volatilization with conventional urea, under certain environmental and soil conditions. Four experiments were carried out in 2007 and 2008, under laboratory conditions, with samples of a Humic Haplumbrept. The treatments varied according to each experiment in terms of soil conditions, such as pH (4.0, 5.5, 6.3 and 6.8), soil water content (5, 10 or 20 % moisture), temperature (18 or 35°C), aside from the fertilizer physical state (solid or liquid) and application method (over the surface or soil-incorporated). The experimental units consisted of plastic trays into which 12 kg of soil (dry basis) were filled in a 15 cm layer. Ammonia gas traps were installed across the soil surface. Frequent measurements were performed during the first 28 days of soil-fertilizer incubation. The peak of ammonia volatilization from the soil occurred in the first week after the application of traditional urea, and two or three days later for urea with urease inhibitor. Ammonia loss was not always higher from conventional than from treated urea, nor from solid than from liquid fertilizers. Ammonia volatilization increased with increases in soil pH, temperature and N rate and was lower at the lowest (5 %) and highest (20 %) soil moisture content. For surface-applied fertilizers, the maximum daily N loss rate was 14 kg ha-1 and the total cumulative loss ranged from 2 to 50 % of the applied N, depending mainly on the physical state of the fertilizer, temperature and on soil moisture. Soil incorporation of urea fertilizers was the best option to minimize ammonia volatilization in all treatments. Source


Barbieri R.,UDESC | Machado R.D.,Federal University of Parana
Latin American Journal of Solids and Structures | Year: 2015

The Modified Global Green's Function Method (MGGFM) is an integral technique that is characterized by good accuracy in the evaluation of boundary fluxes. This method uses only projections of the Green's Function for the solution of the discrete problem and this is the origin of the term 'Modified' of its name. In this paper the local strategy for calculating the projections of Green's function using de Finite Element Method (FEM) are detailed. The numerical examples show some aspects of the method that had not yet been observed and good results for the flux in all nodes of the mesh. © 2015, Brazilian Association of Computational Mechanics.All right reserved. Source


Correa K.S.,Federal University of Goais | Karloh M.,Santa Catarina State University | Martins L.Q.,Federal University of Uberlandia | dos Santos K.,Physical Therapist | Mayer A.F.,UDESC
Revista Brasileira de Fisioterapia | Year: 2011

Background: The Glittre ADL (TGlittre) test is a specifically designed to assess functional limitation in chronic obstructive pulmonary disease (COPD) patients. However, it is not known if it can differentiate the performance of these patients from healthy subjects. Objectives: To investigate whether the Glittre ADL test is able to differentiate the functional capacity of COPD patients from that of healthy subjects and to compare the cardiorespiratory response between Glittre ADL and the six-minute walk test (6MWT). Methods: The study included 10 patients with COPD (GOLD 2 to 4) and 10 healthy subjects matched by age who performed the following: spirometry pre-and post-bronchodilator, a Glittre ADL test and two 6MWT on two consecutive days. Results: The performance of COPD (FEV 1%pred= 38.1±11.8, age=64±10 years, BMI=23.7±5.2 kg/ m 2) was worse than the control group on TGlittre (5.26±2.9 min, 3.3±0.3 min, p<0.05) and 6MWT (434.97±105.18 m vs. 593.25±87.36 m, p<0.05). TGlittre correlated with the physical activity domain of the London Chest Activity of Daily Living (LCADL) scale (r=0.67, p<0.05) and with 6MWT when the total sample was analyzed (r=-0.64, p<0.05). The COPD group had a statistically higher (p<0.05) increase in dyspnea (Borg scale) than the control group for both TGlittre and 6MWT, with a similar heart rate and peripheral oxygen saturation variation in both groups (p>0.05). Conclusions: The performance of COPD patients is worse than that of healthy subjects on the Glittre ADL test, with a greater increase in dyspnea and similar heart rates. © Revista Brasileira de Fisioterapia. Source


Santos G.M.,Santa Catarina State University | Souza A.C.S.,Institute Ensino Superior da Grande Florianopolis IES | Virtuoso J.F.,Physical Therapist | Tavares G.M.S.,Federal University of Pampa | Mazo G.Z.,UDESC
Revista Brasileira de Fisioterapia | Year: 2011

Background: The consequences of falls are a major cause of autonomy and independence loss among the elderly. In this context, the Berg Balance Scale (BBS) has been widely used to detect the risk of falls in elderly. Objective: To evaluate the predictive value of the BBS for fall risk in physically active and inactive elderly subjects. Methods: The sample included 188 older adults with a mean age of 66 (±9) years. Of these, 91 participated in a regular physical activity program and 96 did not. We analyzed the cut-off scores of 45, 47, 49, 51 and 53 in both groups regarding the sensitivity (S), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of the test, including the positive likelihood ratio (PLR) and negative likelihood ratio (RVN) for diagnosing the risk of falls. Results: The mean BBS score was 54.7 in physically active subjects and 50.8 in inactive subjects, which was statistically significant (ρ=0.001). The best cut-off was a score of 49 for physically inactive subjects, with a sensitivity of 91% and a specificity of 92%. On the other hand, the BBS had low sensitivity (from 0 to 15%) and high specificity (between 83% and 100%) for physically active subjects at the cut-off points analyzed. Conclusion: The scale did not achieve sufficient sensitivity to individual differences among physically active older people with higher levels of functional balance ability. ©Revista Brasileira de Fisioterapia. Source


Bertol I.,Santa Catarina State University | Bertol C.,Representacoes Comerciais e Projetos Industriais Ltda | Barbosa F.T.,UDESC
Revista Brasileira de Ciencia do Solo | Year: 2012

The use of rain simulators is fundamental to study rainfall erosion. They are used to monitor the experimental conditions, particularly the rain characteristics and to understand the soil erosion process better. Several types of rainfall simulators have been developed since 1930 around the world. Currently, the Swanson model is the most commonly used. However, a small number of these simulators is fully operational in Brazil, due to the high degree of wear and difficulties of maintenance. The purpose of this study was to develop a new rainfall simulator model, made mostly of aluminum, with no motor to rotate the booms and driven by hydraulic thrust. This "water thrust" rainfall simulator maintains the general features of the Swanson model, mainly those related to the characteristics of the rainfall produced, but with less weight, making the gasoline engine to move the booms superfluous. These properties make this new model lighter, economical, quiet and easier to move about in the experimental area than the model Swanson, since it can be dislocated by only four persons. The rainfall intensity was linearly and positively correlated with the water pressure of the manometer. Source

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