40 research outputs found
Ultrasonic intensification as a tool for enhanced microbial biofuel yields
peer-reviewedUltrasonication has recently received attention as a novel bioprocessing tool for process intensification in many areas
of downstream processing. Ultrasonic intensification (periodic ultrasonic treatment during the fermentation process)
can result in a more effective homogenization of biomass and faster energy and mass transfer to biomass over short
time periods which can result in enhanced microbial growth. Ultrasonic intensification can allow the rapid selective
extraction of specific biomass components and can enhance product yields which can be of economic benefit. This
review focuses on the role of ultrasonication in the extraction and yield enhancement of compounds from various
microbial sources, specifically algal and cyanobacterial biomass with a focus on the production of biofuels. The
operating principles associated with the process of ultrasonication and the influence of various operating conditions
including ultrasonic frequency, power intensity, ultrasonic duration, reactor designs and kinetics applied for ultrasonic
intensification are also described
The Remark about an Analogy between Magnetocaloric Behaviour of Type II Superconductors and Ferromagnetic Materials
The analogy between magnetocaloric behaviour of type II superconductors and anisotropic ferromagnetic materials is discussed. Special attention is devoted to the influence of anisotropy on the negative magnetocaloric effect near phase transitions
Magnetocaloric effect in ferromagnetic and superconducting materials
Computer studies are made illustrating the similarities of the interesting change of sign in the magnetocaloric effect between the vortex lattice in superconductors and a system of interacting magnons and phonons in ferromagnetic materials. This change happens in the superconducting system when the external magnetic field approaches a critical value, while the critical point in the ferromagnetic system is where the external magnetic field turns the direction of magnetization from the easy to the hard direction. The usefulness for the study of high-temperature superconductors is suggested
Magnetocaloric effect in ferromagnetic and superconducting materials
Computer studies are made illustrating the similarities of the interesting change of sign in the magnetocaloric effect between the vortex lattice in superconductors and a system of interacting magnons and phonons in ferromagnetic materials. This change happens in the superconducting system when the external magnetic field approaches a critical value, while the critical point in the ferromagnetic system is where the external magnetic field turns the direction of magnetization from the easy to the hard direction. The usefulness for the study of high-temperature superconductors is suggested
Anaerobic Contribution Determined in Swimming Distances: Relation with Performance
Total anaerobic contribution (TAn) can be assessed by accumulated oxygen deficit, and through sum of glycolytic and phosphagen contribution which enable the evaluation of TAn without influences on mechanical parameters. However, little is known about the difference of TAn within swimming distances. Therefore, the objectives of the present study were to determine and compare the TAn in different performances using the backward extrapolation technique and amount of lactate accumulated during exercise, and relate it with swimming performance. Fourteen competitive swimmers performed five maximal front crawl swims of 50, 100, 200, 400, and 800 m. The total phosphagen (AnAl) and glycolytic (AnLa) contributions were assumed as the fast component of post-exercise oxygen consumption (EPOCFAST) and amount of blood lactate accumulated during exercise, respectively. TAn was the sum of AnAl and AnLa. Significantly lower values of AnLa were observed in the 800 m (p < 0.01) than other distances. For AnAl, the 50 m performance presented the lowest values, followed by 100 and 800 m (p < 0.01). The highest values of AnAl were observed in the 200 and 400 m (p > 0.13). The TAn was significantly higher in the 200 and 400 m performances than observed at 50 and 800 m (p < 0.01). Anaerobic contributions were correlated with 50, 100, 200, and 400 m performances (p < 0.01). The AnAl contribution was not correlated with 400 m performance. Anaerobic parameters were not correlated with 800 m performance. In conclusion, the highest values of anaerobic contribution were observed in the 200 and 400 m distances. Moreover, TAn is important to performances below 400 m, and may be used in training routines
Running-based anaerobic sprint test as a procedure to evaluate anaerobic power
The aim of this study was to evaluate the use of the running anaerobic sprint test (RAST) as a predictor of anaerobic capacity, compare it to the maximal accumulated oxygen deficit (MAOD) and to compare the RAST's parameters with the parameters of 30-s all-out tethered running on a treadmill. 39 (17.0+/-1.4 years) soccer players participated in this study. The participants underwent an incremental test, 10 submaximal efforts [50-95% of velocity correspondent to VO2MAX (vVO(2MAX))] and one supramaximal effort at 110% of vVO2MAX for the determination of MAOD. Furthermore, the athletes performed the RAST. In the second stage the 30-s all-out tethered running was performed on a treadmill (30-s all-out), and compared with RAST. No significant correlation was observed between MAOD and RAST parameters. However, significant correlations were found between the power of the fifth effort (P5) of RAST with peak and mean power of 30-s all-out (r = 0.73 and 0.50; p < 0.05, respectively). In conclusion, the parameters from RAST do not have an association with MAOD, suggesting that this method should not be used to evaluate anaerobic capacity. Although the correlations between RAST parameters with 30-s all-out do reinforce the RAST as an evaluation method of anaerobic metabolism, such as anaerobic power361411561162FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2010/08761-2Laboratory of Exercise Physiology (LAFE
Running-based anaerobic sprint test as a procedure to evaluate anaerobic power
The aim of this study was to evaluate the use of the running anaerobic sprint test (RAST) as a predictor of anaerobic capacity, compare it to the maximal accumulated oxygen deficit (MAOD) and to compare the RAST's parameters with the parameters of 30-s all-out tethered running on a treadmill. 39 (17.0±1.4 years) soccer players participated in this study. The participants underwent an incremental test, 10 submaximal efforts [50-95% of velocity correspondent to VO2MAX (vVO2MAX)] and one supramaximal effort at 110% of vVO2MAX for the determination of MAOD. Furthermore, the athletes performed the RAST. In the second stage the 30-s all-out tethered running was performed on a treadmill (30-s all-out), and compared with RAST. No significant correlation was observed between MAOD and RAST parameters. However, significant correlations were found between the power of the fifth effort (P5) of RAST with peak and mean power of 30-s all-out (r=0.73 and 0.50; p<0.05, respectively). In conclusion, the parameters from RAST do not have an association with MAOD, suggesting that this method should not be used to evaluate anaerobic capacity. Although the correlations between RAST parameters with 30-s all-out do reinforce the RAST as an evaluation method of anaerobic metabolism, such as anaerobic power