Vascular effects and electrolyte homeostasis of the natriuretic peptide isolated from Crotalus oreganus abyssus (North American Grand Canyon rattlesnake) venom

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Development and energy balance of sugarcane in the norte fluminense, Brazil

The growing concern for renewable and cleaner energy sources has increased the demand for biofuels, pointing out the ethanol from sugarcane. The aim of this study was quantify the partition of energy balance components and monitor the physiological development indexes of the sugarcane, relating them to water availability conditions of climate and soil in Campos dos Goytacazes, Norte Fluminense, Brazil. To this end, a micrometeorological station was settled in an area of 13 ha in commercial cultivation. The culture was regularly monitored at 85, 102, 128, 149, 174, 194, 215, 235, 255 and 280 days after cutting (DAC). The variations in water availability directly influenced the rates of crop growth and energy balance. Under the conditions studied most of the available energy (53%) was consumed by the latent heat flux.

Interference of high-heeled shoes in static balance among young women

The aim of the present study was to assess the effect of the use of high-heeled shoes on static balance in young adult women. Fifty-three women between 18 and 30 years of age and accustomed to wearing high-heeled shoes participated in the study. None of the participants had any orthopedic or neurologic alterations. Static balance was assessed using a force plate. Oscillations from the center of pressure in the mediolateral and anteroposterior directions were measured both when barefoot and when wearing high-heeled shoes [7 centimeters (cm) in height and 1 cm in diameter] under the conditions of eyes open and eyes closed. Two-way analysis of variance was employed for the statistical analysis, with the level of significance set at 5% (p < .05). The results revealed statistically significant differences between tests when barefoot and when wearing high-heeled shoes as well as with eyes open and eyes closed (p < .01). With the use of high-heeled shoes, there was a significant increase in mediolateral oscillation with eyes closed (p < .01). The present study demonstrates that the use of seven-cm high heels altered static balance in the healthy young women analyzed, increasing the oscillation of the center of pressure, regardless of visual restriction. (C) 2012 Elsevier B.V. All rights reserved.

WATER BALANCE and SPATIAL DISTRIBUTION of AN ANURAN COMMUNITY FROM BRAZIL

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Greenhouse gas balance due to the conversion of sugarcane areas from burned to green harvest, considering other conservationist management practices

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Static balance and function in children with cerebral palsy submitted to neuromuscular block and neuromuscular electrical stimulation: Study protocol for prospective, randomized, controlled trial

Background: The use of botulinum toxin A (BT-A) for the treatment of lower limb spasticity is common in children with cerebral palsy (CP). Following the administration of BT-A, physical therapy plays a fundamental role in potentiating the functionality of the child. The balance deficit found in children with CP is mainly caused by muscle imbalance (spastic agonist and weak antagonist). Neuromuscular electrical stimulation (NMES) is a promising therapeutic modality for muscle strengthening in this population. The aim of the present study is to describe a protocol for a study aimed at analyzing the effects of NMES on dorsiflexors combined with physical therapy on static and functional balance in children with CP submitted to BT-A.Methods/Design: Protocol for a prospective, randomized, controlled trial with a blinded evaluator. Eligible participants will be children with cerebral palsy (Levels I, II and III of the Gross Motor Function Classification System) between five and 12 years of age, with independent gait with or without a gait-assistance device. All participants will receive BT-A in the lower limbs (triceps surae). The children will then be randomly allocated for either treatment with motor physical therapy combined with NMES on the tibialis anterior or motor physical therapy alone. The participants will be evaluated on three occasions: 1) one week prior to the administration of BT-A; 2) one week after the administration of BT-A; and 3) four months after the administration of BT-A (end of intervention). Spasticity will be assessed by the Modified Ashworth Scale and Modified Tardieu Scale. Static balance will be assessed using the Medicapteurs Fusyo pressure platform and functional balance will be assessed using the Berg Balance Scale.Discussion: The aim of this protocol study is to describe the methodology of a randomized, controlled, clinical trial comparing the effect of motor physical therapy combined with NMES on the tibialis anterior muscle or motor physical therapy alone on static and functional balance in children with CP submitted to BT-A in the lower limbs. This study describes the background, hypotheses, methodology of the procedures and measurement of the results.

Effect of electrolyte on the gelation and aggregation of SnO2 colloidal suspensions

Electrolytes may modify the physical-chemical characteristics of colloidal particle interfaces in suspension, which can favour gel or aggregate formation. The influence of NH4Cl loading on the aggregation and gelation of SnO2 colloidal suspensions was investigated using measurements of rheology, turbidity and infrared spectra. A rapid aggregate growth for samples with Cl- > 20 mM was observed. With increasing age, gelation was observed due to formation of interaggregate bonds. For concentration of Cl- between 20 and 9 mM, the aggregation process was slower allowing the formation of gel with a network which was not destroyed as the gel was submitted to a small rate of shear. As aging continues, the condensation reaction between OH groups gave rise to the formation of Sn-O bonds, irrespective of the electrolyte loading. © 1992 Elsevier Science Publishers B.V. All rights reserved.

Drying of SnO2 hydrogels: effect of the electrolyte

The effect of the electrolyte (NH+ 4, Cl-) on the drying of SnO2 hydrogels was investigated by linear shrinkage, mass loss, gravimetric thermal analysis and infrared spectroscopy. Results show that the drying mechanism for monolithic SnO2 gels is highly dependent on the concentration of the electrolyte solution inside the pores. For higher concentrations, the drying process is governed by capillary forces while for the smaller ones (≤20 mM) syneresis shrinkage becomes predominant just before the end of the first drying period. This phenomenon is related to condensation reaction among the superficial OH groups and may hamper formation of monolithic SnO2. © 1992 Elsevier Science Publishers B.V. All rights reserved.

Electric and magnetic properties of polymer electrolyte/carbon black composites

Measurements of 1H Nuclear Magnetic Resonance (NMR) relaxation times, Electron Paramagnetic Resonance (EPR) and AC Impedance Spectroscopy (IS) are reported for composites based on PEO8:LiClO4 and carbon black (CB), prepared by two methods: solvent and fusion processing. Three nuclear relaxation processes were identified for 1H nuclei: (i) belonging to the polymer chains in the amorphous phase, loosely bound to the CB particles, whose dynamics is almost the same as for unfilled polymer, (ii) belonging to the polymer chains which are tightly attached to the CB particles, and (iii) belonging to the crystalline phase in the loose polymer chain. The paramagnetic electronic susceptibility of the composite samples, measured by EPR, was interpreted by assuming a contribution of localized spin states that follow a Curie law, and a Pauli-like contribution of delocalized spins. A significant change of the EPR linewidth was observed at 40 K, which is the temperature where the Curie and Pauli susceptibilities equally contribute to the paramagnetic electronic susceptibility. The electrical properties are very sensitive to the preparation methods of the composites, which conditions the interaction between carbon particle-carbon particle and carbon particle-polymer chain. Classical statistic models to describe the conductivity in these media were not satisfactory. © 1998 Published by Elsevier Science B.V. All rights reserved.

Calibration uncertainty estimation for internal aerodynamic balance

Aerodynamic balances are employed in wind tunnels to estimate the forces and moments acting on the model under test. This paper proposes a methodology for the assessment of uncertainty in the calibration of an internal multi-component aerodynamic balance. In order to obtain a suitable model to provide aerodynamic loads from the balance sensor responses, a calibration is performed prior to the tests by applying known weights to the balance. A multivariate polynomial fitting by the least squares method is used to interpolate the calibration data points. The uncertainties of both the applied loads and the readings of the sensors are considered in the regression. The data reduction includes the estimation of the calibration coefficients, the predicted values of the load components and their corresponding uncertainties, as well as the goodness of fit.

Exercise programs improve mobility and balance in people with Parkinson's disease

Compromised balance and loss of mobility are among the major consequences of Parkinson's disease (PD). The literature documents numerous effective interventions for improving balance and mobility. The purpose of this study was to verify the effectiveness of two exercise programs on balance and mobility in people with idiopathic PD. Thirty-four participants, with idiopathic PD that ranged from Stage I to Stage III on the Hoehn & Yahr (H&Y) scale, were assigned to two groups. Group 1 (n = 21; 67±9 years old) was engaged in an intensive exercise program (aerobic capacity, flexibility, strength, motor coordination and balance) for 6 months: 72 sessions, 3 times a week, 60 minutes per session; while Group 2 (n = 13; 69±8 years old) participated in an adaptive program (flexibility, strength, motor coordination and balance) for 6 months: 24 sessions, once a week, 60 minutes per session. Balance and basic functional mobility were assessed in pre- and post-tests by means of the Berg Balance Scale and the Timed Up and Go Test. Before and after the interventions, groups were similar in clinical conditions (H&Y, UPDRS, and Mini-Mental). A MANOVA 2 (programs) by 2 (moments) revealed that both groups were affected by the exercise intervention. Univariate analyses showed that participants improved their mobility and balance from pre- to post-test. There were no differences between groups in either mobility or balance results. Both the intensive and adaptive exercise programs improved balance and mobility in patients with PD. © 2009 Elsevier Ltd. All rights reserved.

Effects of acute normovolemic anemia on hemodynamic parameters and acid-base balance in dogs

The aim of this study was to evaluate the hemodynamic and acid-base status of dogs subjected to acute normovolemic anemia. The dogs (n = 10) were evaluated 15 minutes and 24 hours after induction of anemia (hematocrit below 18) with blood withdrawal and simultaneously replacement of same volume of Ringer's lactate solution and hydroxyethyl starch-based solution in a 2:1 ratio. The cardiac output was measured by Doppler echocardiography and blood pressure by oscillometric device, and posteriorly hemodynamic parameters were calculated. The anemic groups had increase in cardiac index (P <.05) (3.82 ± 1.05 to 5.86 ± 1.49 and 5.81 ± 1.63 L/min m) and decreases (P <.05) in the indices of total peripheral resistance (6797.81 ± 3060.22 to 3220.14 ± 1275.02 and 3887.74 ± 1394.89 dinaseg/cm 5× m2) and oxygen delivery (7942.84 ± 3344.00 to 4021.68 ± 1627.00 and 4430.82 ± 1402.61 mL/min× m 2), respectively. There were no significant changes in pH, but PaO2 and SaO2 values were increased, and PaCO2 reduced in anemic dogs (P <.05). Therefore, acute normovolemic anemia can create significant hemodynamic changes and despite some hemogasometric changes, there were no changes in the acid-base status in dogs. Copyright © 2011 Tatiana Champion et al.

Postural control under visual and proprioceptive perturbations during double and single limb stances: Insights for balance training

Single Limb Stance under visual and proprioceptive disturbances is largely used in clinical settings in order to improve balance in a wide range of functional disabilities. However, the proper role of vision and proprioception in SLS is not completely understood. The objectives of this study were to test the hypotheses that when ankle proprioception is perturbed, the role of vision in postural control increases according to the difficulty of the standing task. And to test the effect of vision during postural adaptation after withdrawal of the somesthetic perturbation during double and single limb stance. Eleven males were submitted to double (DLS) and single limb (SLS) stances under conditions of normal or reduced vision, both with normal and perturbed proprioception. Center of pressure parameters were analyzed across conditions. Vision had a main effect in SLS, whereas proprioception perturbation showed effects only during DLS. Baseline stability was promptly achieved independently of visual input after proprioception reintegration. In conclusion, the role of vision increases in SLS. After proprioception reintegration, vision does not affect postural recovery. Balance training programs must take that into account. © 2011 Elsevier Ltd.