Authors:A. Coelho, I. Moreira, J. de Araujo, and M. de Araujo
The57Fe Mössbauer spectra of substituted pentacyanoferrate /II/ complexes [/CN/5 FeII L]3– have been obtained for L=adenine, guanine, purine, caffeine, ethylene sulphide, dimethyl sulphoxide, and ammonia. The Mössbauer parameters are utilized to classify the various ligands according to their and bonding abilities. A linear correlation between the Mössbauer isomer shift and the tetragonal distortion caused by the ligand L is proposed. Comparison between this linear correlation and the approximative method of Wentworth and Piper1 is made.
Authors:D. Lima, J. Coelho, A. Pereira, M. Silvestre, and D. Nelson
With a view to increasing the industrial use of bovine blood globin, the extraction of the globin fraction was achieved using the acidified acetone method. Spectrophotometric analysis of the globin and the extracted heme group was performed utilizing the Soret band. The influence of the type of final processing of the globins (freeze drying, gel) on the solubility, the emulsification capacity, the emulsifying activity index and the stability of the emulsion was studied at pH 5, 6 and 7. No behavioural differences between freeze-dried and gel globin forms were observed. The best performance for most of the functional properties was achieved at pH 5.0 for the globin obtained by this method.
Authors:A. Delben, F. Menezes, J. Delben, M. Coelho, and R. Ribeiro
Waste compromises environmental preservation as well human health in
many countries. Recycling is an alternative that sometimes represents the
only economical activity for a significant population in the big cities. Almost
3% of waste materials in Brazil are vitreous. Ceramic production adding waste
glass is possible with advantages of costs reduction associated to decrease
on firing temperatures and to the raw material itself. At present paper up
to 80 mass% of waste glass was added to clay. The sintering temperature decreased
linearly and the shrinkage increased with glass content, an effect more pronounced
for high glass amount.
Authors:J. Delben, P. Candelorio, F. de Oliveira, T. Spontoni, Angela Delben, M. Coelho, and L. Andrade
Petroleum natural gas (PNG) reserves will last even when the oil reserves are exhausted, requiring the development of technologies
for PNG storage. Activated charcoal is the best material for such a purpose. Under vacuum samples of aroeira (Astronium Urundeuva)
underwent pyrolysis in diverse conditions. The samples were characterized by thermal analysis, scanning electronic microscopy
and infrared spectroscopy. When the pyrolysis temperature increased, mechanical anisotropy resistance tended to disappear.
The pyrolysis became complete only at high temperatures and using a long time of treatment.
Authors:Juan Martín-Hernández, P. Marín, H. Menéndez, J. Loenneke, M. Coelho-e-Silva, D. García-López, and A. Herrero
In order to ascertain whether differing structural mechanisms could underlie blood flow restricted training (BFRT) and high intensity training (HIT), this study had two aims: (i) to gain an insight into the acute variations of muscle architecture following a single bout of two different volumes of BFRT, and (ii) to compare these variations with those observed after HIT. Thirty-five young men volunteered for the study and were randomly divided into three groups: BFRT low volume (BFRT LV), BFRT high volume (BFRT HV) and traditional high intensity resistance training (HIT). All subjects performed a bilateral leg extension exercise session with a load of 20% of one repetition maximum (1RM) in the BFRT groups, whereas the load of the HIT group was equivalent to an 85% of their 1RM. Before and immediately after the exercise bout, ultrasound images were taken from the rectus femoris (RF) and the vastus lateralis (VL). All groups increased their RF (p < 0.001) and VL (p < 0.001) muscle thickness, while the increases in pennation angle were larger in HIT as compared to BFRT LV (p = 0.013) and BFRT HV (p = 0.037). These results support the hypothesis that acute muscle cell swelling may be involved in the processes underlying BFRT induced muscle hypertrophy. Furthermore, our data indicate differing structural responses to exercise between BFRT and HIT.
Authors:J.P. Duarte, Manuel Coelho-e-Silva, V. Severino, D. Martinho, L. Luz, J.R. Pereira, R. Baptista, J. Valente-dos-Santos, A.M. Machado-Rodrigues, V. Vaz, A. Cupido-dos-Santos, J. Martín-Hernández, S.P. Cumming, and R.M. Malina
The study was aimed to investigate the reproducibility of performance parameters obtained from 10-s maximal cycling effort against different braking forces in young adult athletes. The sample (n = 48) included male athletes aged 18.9–29.9 years (175.5 ± 6.9 cm, 76.2 ± 10.1 kg). The exercise protocol was performed in a cycle-ergometer against a random braking force (4% to 11% of body mass). Intra-individual variation was examined from repeated tests within one week. Descriptive statistics were computed and differences between sessions were tested using paired t-test. The coefficient of correlation between repeated measures, technical error of measurement (TEM), coefficient of variation and ICC were calculated. Agreement between trials was examined using the Bland-Altman procedure. Mean values of peak power were relatively stable when obtained from sampling rates of 50 Hz and ranged between 1068 watt and 1082 watt (t(47) = 1.149, p = 0.256, ES-r = 0.165) or while corresponding to a sampling rate of 1 Hz (t(47) = 0.742, p = 0.462, ES-r = 0.107). Correlations between repeated measures were high (+0.907, 95% CI: +0.839 to +0.947) and TEM about 59.3 watt (%CV = 5.52%; ICC = 0.951, 95% CI: 0.912 to 0.972). The present study suggests that reproducibility of peak power in male adult athletes tended to be acceptable and within individual error appeared unrelated to braking force.