Monitoring the impact of bioaugmentation with a PAH-degrading strain on different soil microbiomes using pyrosequencing

The effect of bioaugmentation with Sphingobium sp. AM strain on different soils microbiomes, pristine soil (PS), chronically contaminated soil (IPK) and recently contaminated soil (Phe) and their implications in bioremediation efficiency was studied by focusing on the ecology that drives bacterial communities in response to inoculation. AM strain draft genome codifies genes for metabolism of aromatic and aliphatic hydrocarbons. In Phe, the inoculation improved the elimination of phenanthrene during the whole treatment, whereas in IPK no improvement of degradation of any PAH was observed. Through the pyrosequencing analysis, we observed that inoculation managed to increase the richness and diversity in both contaminated microbiomes, therefore, independently of PAH degradation improvement, we observed clues of inoculant establishment, suggesting it may use other resources to survive. On the other hand, the inoculation did not influence the bacterial community of PS. On both contaminated microbiomes, incubation conditions produced a sharp increase on Actinomycetales and Sphingomonadales orders, while inoculation caused a relative decline of Actinomycetales. Inoculation of most diverse microbiomes, PS and Phe, produced a coupled increase of Sphingomonadales, Burkholderiales and Rhizobiales orders, although it may exist a synergy between those genera; our results suggest that this would not be directly related to PAH degradation.Facultad de Ciencias ExactasCentro de Investigación y Desarrollo en Fermentaciones Industriale

Monitoring the impact of bioaugmentation with a PAH-degrading strain on different soil microbiomes using pyrosequencing

The effect of bioaugmentation with Sphingobium sp. AM strain on different soils microbiomes, pristine soil (PS), chronically contaminated soil (IPK) and recently contaminated soil (Phe) and their implications in bioremediation efficiency was studied by focusing on the ecology that drives bacterial communities in response to inoculation. AM strain draft genome codifies genes for metabolism of aromatic and aliphatic hydrocarbons. In Phe, the inoculation improved the elimination of phenanthrene during the whole treatment, whereas in IPK no improvement of degradation of any PAH was observed. Through the pyrosequencing analysis, we observed that inoculation managed to increase the richness and diversity in both contaminated microbiomes, therefore, independently of PAH degradation improvement, we observed clues of inoculant establishment, suggesting it may use other resources to survive. On the other hand, the inoculation did not influence the bacterial community of PS. On both contaminated microbiomes, incubation conditions produced a sharp increase on Actinomycetales and Sphingomonadales orders, while inoculation caused a relative decline of Actinomycetales. Inoculation of most diverse microbiomes, PS and Phe, produced a coupled increase of Sphingomonadales, Burkholderiales and Rhizobiales orders, although it may exist a synergy between those genera; our results suggest that this would not be directly related to PAH degradation.Facultad de Ciencias ExactasCentro de Investigación y Desarrollo en Fermentaciones Industriale

Effects of Different Training Intensity Distribution in Recreational Runners

Purpose: To compare the impact of two different training intensity distributions in terms of conditional and performance parameters and spent time to training in recreational athletes. Methods: Two different training intensity distribution model were performed for 8 weeks by 38 recreational runners. Runners recruited were randomly assigned to 2 different training models based on HR intensity detected with maximal test. The percentage distribution splitted in zone 1, 2 and 3 were by 77/3/20 and 40/50/10 in polarized endurance training group (PET) and focused endurance training (FOC) group respectively. Programs were balanced for total training impulse (TRIMP). To evaluate effects of training, before and after treatment were performed a maximal exercise test to determine Maximal Oxygen Uptake (V'O2max), Ventilatory Threshold (VT), respiratory-compensation point (RCT) Running Economy (RE) and 2 Km performance. To investigate the effects of training on muscular performance were performed one repetition maximum (1RM), squat jump (SJ) and counter movement jump (CMJ). Results: Both groups significantly improved their velocity at V'O2max (3.2% and 4.0%), at VT (4.0% and 3.2%), RCT (5.7% and 3.4%), the average velocity in 2 Km performance (3.5% and 3.0%) and RE (-5.3% and -8.7%) for PET and FOC respectively for each variable. No differences were found between the groups on any parameter investigated except about the total training time (PET = 29.8 3.1h and FOC = 24.8 2.0 h). Conclusion: Focused Endurance Training obtains similar improvements than Polarized Endurance Training saving 17% of training time in recreational runners

Monitoring the impact of bioaugmentation with a PAH-degrading strain on different soil microbiomes using pyrosequencing

The effect of bioaugmentation with Sphingobium sp. AM strain on different soils microbiomes, pristine soil (PS), chronically contaminated soil (IPK) and recently contaminated soil (Phe) and their implications in bioremediation efficiency was studied by focusing on the ecology that drives bacterial communities in response to inoculation. AM strain draft genome codifies genes for metabolism of aromatic and aliphatic hydrocarbons. In Phe, the inoculation improved the elimination of phenanthrene during the whole treatment, whereas in IPK no improvement of degradation of any PAH was observed. Through the pyrosequencing analysis, we observed that inoculation managed to increase the richness and diversity in both contaminated microbiomes, therefore, independently of PAH degradation improvement, we observed clues of inoculant establishment, suggesting it may use other resources to survive. On the other hand, the inoculation did not influence the bacterial community of PS. On both contaminated microbiomes, incubation conditions produced a sharp increase on Actinomycetales and Sphingomonadales orders, while inoculation caused a relative decline of Actinomycetales. Inoculation of most diverse microbiomes, PS and Phe, produced a coupled increase of Sphingomonadales, Burkholderiales and Rhizobiales orders, although it may exist a synergy between those genera; our results suggest that this would not be directly related to PAH degradation.Facultad de Ciencias ExactasCentro de Investigación y Desarrollo en Fermentaciones Industriale

Neuromuscular Fatigue Does Not Impair the Rate of Force Development in Ballistic Contractions of Submaximal Amplitudes

The effect of muscle fatigue on rate of force development (RFD) is usually assessed during tasks that require participants to reach as quickly as possible maximal or near-maximal force. However, endurance sports require athletes to quickly produce force of submaximal, rather than maximal, amplitudes. Thus, this study investigated the effect of muscle fatigue induced by long-distance running on the capacity to quickly produce submaximal levels of force. Twenty-one male amateur runners were evaluated before and shortly after a half-marathon race. Knee extensors force was recorded under maximal voluntary and electrically evoked contractions. Moreover, a series of ballistic contractions at different submaximal amplitudes (from 20 to 100% of maximal voluntary force) was obtained, by asking the participants to reach submaximal forces as fast as possible. The RFD was calculated for each contraction. After the race, maximal voluntary activation, resting doublet twitch, maximal force, and RFD during maximal contraction decreased (-12, -12, -21, and -19%, respectively, all P-values < 0.0001). Nevertheless, the RFD values measured during ballistic contractions up to 60% of maximal force were unaffected (all P-values > 0.4). Long-distance running impaired the capacity to quickly produce force in ballistic contractions of maximal, but not of submaximal, amplitudes. Overall, these findings suggest that central and peripheral fatigue do not affect the quickness to which muscle contracts across a wide range of submaximal forces. This is a relevant finding for running and other daily life activities that rely on the production of rapid submaximal contractions rather than maximal force levels

Human talar ontogeny: Insights from morphological and trabecular changes during postnatal growth

The study of the development of human bipedalism can provide a unique perspective on the evolution of morphology and behavior across species. To generate new knowledge of these mechanisms, we analyze changes in both internal and external morphology of the growing human talus in a sample of modern human juveniles using an innovative approach. The sample consists of high‐resolution microCT scans of 70 modern juvenile tali, aged between 8 postnatal weeks and 10 years old, from a broad chronological range from Middle/Late Neolithic, that is, between 4800 and 4500 BCE, to the 20th century. We applied geometric morphometric and whole‐bone trabecular analysis (bone volume fraction, degree of anisotropy, trabecular number, thickness, and spacing) to all specimens to identify changes in the external and internal morphology during growth. Morphometric maps were also generated. During the first year of life, the talus has an immature and globular shape, with a dense, compact, and rather isotropic trabecular architecture, with numerous trabeculae packed closely together. This pattern changes while children acquire a more mature gait, and the talus tends to have a lower bone volume fraction, a higher anisotropy, and a more mature shape. The changes in talar internal and external morphologies reflect the different loading patterns experienced during growth, gradually shifting from an “unspecialized” morphology to a more complex one, following the development of bipedal gait. Our research shows that talar plasticity, even though genetically driven, may show mechanical influences and contribute to tracking the main locomotor milestones

Neuromuscular fatigue does not impair the rate of force development in ballistic contractions of submaximal amplitudes

The effect of muscle fatigue on rate of force development (RFD) is usually assessed during tasks that require participants to reach as quickly as possible maximal or nearmaximal force. However, endurance sports require athletes to quickly produce force of submaximal, rather than maximal, amplitudes. Thus, this study investigated the effect of muscle fatigue induced by long-distance running on the capacity to quickly produce submaximal levels of force. Twenty-one male amateur runners were evaluated before and shortly after a half-marathon race. Knee extensors force was recorded under maximal voluntary and electrically evoked contractions. Moreover, a series of ballistic contractions at different submaximal amplitudes (from 20 to 100% of maximal voluntary force) was obtained, by asking the participants to reach submaximal forces as fast as possible. The RFD was calculated for each contraction. After the race, maximal voluntary activation, resting doublet twitch, maximal force, and RFD during maximal contraction decreased (-12, -12, -21, and -19%, respectively, all P-values 0.4). Long-distance running impaired the capacity to quickly produce force in ballistic contractions of maximal, but not of submaximal, amplitudes. Overall, these findings suggest that central and peripheral fatigue do not affect the quickness to which muscle contracts across a wide range of submaximal forces. This is a relevant finding for running and other daily life activities that rely on the production of rapid submaximal contractions rather than maximal force levels