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Cruz Alta, Brazil

Ribeiro J.P.,Laboratory of Exercise Physiopathology | Ribeiro J.P.,Federal University of Rio Grande do Sul | Chiappa G.R.,Laboratory of Exercise Physiopathology | Callegaro C.C.,Laboratory of Exercise Physiopathology | Callegaro C.C.,University of Cruz Alta
Brazilian Journal of Physical Therapy | Year: 2012

Background: Heart failure induces histological, metabolic and functional adaptations in the inspiratory muscles. This inspiratory muscle weakness, which occurs in 30% to 50% of the heart failure patients, is associated with reduction in the functional capacity, reduction in the quality of life and with a poor prognosis in these individuals. Objectives: The objective of this review was to discuss the pathophysiological mechanisms that may explain the role of the inspiratory muscles in the exercise limitation with focus in the reflexes that control the ventilation and the circulation during the exercise. Method: We performed searches in the PUBMED database using the terms "inspiratory muscles", "inspiratory muscle training", "metaboreflex" and "chemoreflex" and including studies published since 1980. Results: Inspiratory muscle weakness is associated with exercise intolerance and with an exaggerated inspiratory chemoreflex and metaboreflex in heart failure. The inspiratory metaboreflex may be attenuated by the inspiratory muscle training or by the aerobic exercise training improving the exercise performance. Conclusions: Patients with heart failure may present changes in the inspiratory muscle function associated with inspiratory chemoreflex and metaboreflex hyperactivity, which exacerbate the exercise intolerance. Source

de Campos B.-H.C.,Federal University of Rio Grande do Sul | Amado T.J.C.,Federal University of Santa Maria | Bayer C.,Federal University of Rio Grande do Sul | Nicoloso R.S.,Embrapa Swine and Poultry | Fiorin J.E.,University of Cruz Alta
Revista Brasileira de Ciencia do Solo | Year: 2011

Soil organic matter (SOM) plays a crucial role in soil quality and can act as an atmospheric C-CO 2 sink under conservationist management systems. This study aimed to evaluate the long-term effects (19 years) of tillage (CT-conventional tillage and NT-no tillage) and crop rotations (R0-monoculture system, R1-winter crop rotation, and R2-intensive crop rotation) on total, particulate and mineralassociated organic carbon (C) stocks of an originally degraded Red Oxisol in Cruz Alta, RS, Southern Brazil. The climate is humid subtropical Cfa 2a (Köppen classification), the mean annual precipitation 1,774 mm and mean annual temperature 19.2 °C. The plots were divided into four segments, of which each was sampled in the layers 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. Sampling was performed manually by opening small trenches. The SOM pools were determined by physical fractionation. Soil C stocks had a linear relationship with annual crop C inputs, regardless of the tillage systems. Thus, soil disturbance had a minor effect on SOM turnover. In the 0-0.30 m layer, soil C sequestration ranged from 0 to 0.51 Mg ha -1 yr -1, using the CT R0 treatment as base-line; crop rotation systems had more influence on soil stock C than tillage systems. The mean C sequestration rate of the cropping systems was 0.13 Mg ha -1 yr -1 higher in NT than CT. This result was associated to the higher C input by crops due to the improvement in soil quality under long-term no-tillage. The particulate C fraction was a sensitive indicator of soil management quality, while mineral-associated organic C was the main pool of atmospheric C fixed in this clayey Oxisol. The C retention in this stable SOM fraction accounts for 81 and 89 % of total C sequestration in the treatments NT R1 and NT R2, respectively, in relation to the same cropping systems under CT. The highest C management index was observed in NT R2, confirming the capacity of this soil management practice to improve the soil C stock qualitatively in relation to CT R0. The results highlighted the diversification of crop rotation with cover crops as a crucial strategy for atmospheric C-CO 2 sequestration and SOM quality improvement in highly weathered subtropical Oxisols. Source

Binelo M.O.,Federal University of Ceara | Binelo M.O.,University of Cruz Alta | De Almeida A.L.F.,Federal University of Ceara | Cavalcanti F.R.P.,Federal University of Ceara
IEEE Transactions on Vehicular Technology | Year: 2011

This paper discusses the design of multiple-input-multiple-output (MIMO) antenna systems and proposes a genetic algorithm to obtain the position and orientation of each MIMO array antenna that maximizes the ergodic capacity for a given propagation scenario. One challenging task in the MIMO system design is to accommodate the multiple antennas in the mobile device without compromising the system capacity, due to spatial and electrical constraints. Based on an interface between the antenna model and the propagation channel model, the ergodic capacity is considered as the objective function of the MIMO array optimization. Simulation results corroborate the importance of polarization and antenna pattern diversities for MIMO in small terminals. Our results also show that the electromagnetic coupling effect can be exploited by the optimizer to decrease signal correlation and increase MIMO capacity. A comparison among a uniform linear array (ULA), a uniform circular array (UCA), and a genetic algorithm (GA)-optimized array is also carried out, showing that the topology given by the optimizer is superior to that of the standard ULA and UCA for the considered propagation channel. © 2011 IEEE. Source

Bianchi M.A.,University of Cruz Alta | Fleck N.G.,Federal University of Rio Grande do Sul | Agostinetto D.,Federal University of Pelotas
Planta Daninha | Year: 2011

The strong dependence on herbicides for weed control in soybean has led to the selection of tolerant and/or resistant weed plants. Besides the use of herbicides, integrated management includes techniques such as cultivar competitive ability to control weed plants. This work aimed to evaluate cultivar response to competition with forage turnip (Raphanus sativus) and to identify carriers of superior competitive ability. The experiment was carried out under field conditions in Cruz Alta-RS, during the 2000/01 season. Two competition conditions (absence and presence of forage turnip during the soybean vegetative growth stage) were tested in combination with 11 soybean cultivars. The effect of forage turnip competition varies among cultivars, characterizing genetic variability, which permits the selection of genotypes with higher competitive ability. Forage turnip competition reduces plant height, twig average length and soybean grain yield. Among the soybean genotypes used, the cultivar M Soy 6101 shows outstanding competitive ability due to its higher grain yield potential, both with and without forage turnip competition. Source

Garlet T.M.B.,University of Cruz Alta | Flores R.,Federal University of Santa Maria | Messchmidt A.A.,UNICRUZ
Revista Brasileira de Plantas Medicinais | Year: 2011

Mentha x gracilis Sole is a hybrid that produces essential oils rich in monoterpenes. Aimed at the clonal propagation of this plant, nodal segments from aseptic plants were cultured in Murashige and Skoog (MSO) medium supplemented with 0; 0.5; 1.0 and 2.0 μM kinetin, benzyl adenine (BAP) or thidiazuron (TDZ). After 30 days, plants were transferred to MOS medium without cytokinin supplementation. The best results were obtained in medium supplemented with 2 μM TDZ, which proved to be a viable method for the rapid production of a large number of seedlings. After transference to the greenhouse, plants propagated with TDZ had a larger number of glandular trichomes. Source

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