Genetic diversity of Bromeliaceae species from the Atlantic Forest.

The Bromeliaceae family includes a range of species used for many purposes, including ornamental use and use as food, medicine, feed, and fiber. The state of Espírito Santo, Brazil is a center of diversity for this family in the Atlantic Forest. We evaluated the genetic diversity of five populations of the Bromeliaceae family, including specimens of the genera Aechmea, Billbergia (subfamily Bromelioideae), and Pitcairnia (subfamily Pitcairnioidea), all found in the Atlantic Forest and distributed in the state of Espírito Santo. The number of alleles per locus in populations ranged from two to six and the fixation index (F), estimated for some simple sequence repeats in bromeliad populations, was less than zero in all populations. All markers in the Pitcairnia flammea population were in Hardy-Weinberg equilibrium (P < 0.05). Moreover, significant deviations from Hardy-Weinberg equilibrium were observed at some loci in populations of the five bromeliad species. In most cases, this can be attributed to the presence of inbreeding or the Wahlund effect. The genetic diversity indices of five species showed greater allelic richness in P. flammea (3.55). Therefore, we provide useful information for the characterization of genetic diversity in natural populations of Aechmea ramosa, Aechmea nudicaulis, Billbergia horrid, Billbergia euphemia, and P. flammea in Atlantic Forest remnants in the south of Espírito Santo state.

Neuromuscular mechanisms and anthropometric modifications in the initial stages of independent gait.

The gait acquisition is an important milestone of motor development. Structural modifications observed during this period add complexity to the process, and the child needs to use appropriate neuromuscular strategies to walk independently. The objective of this study was to document the longitudinal modifications in neuromuscular mechanisms and in functional anthropometric measures during independent gait acquisition in typically developing children. Twelve children were followed for 2 months after gait acquisition, with its initial period documented by the standardized test Alberta Infant Motor Scale. Quantification of the EMG signals of six muscles in the right lower limb allowed the calculation of the co-contraction indexes (CCI) considering pairs of antagonistic muscles, representing the hip, knee and ankle joints. The CCIs were summed up to yield a total index. Anthropometric measures were transformed into gravitational torque (mLg) values for stance and swing phases of gait. Statistical analyses included repeated measures ANOVA models with one factor (week post-acquisition) for the dependent variables mLg and normalized CCI (CCI/mLg). A significant increase was observed in the mLg during the period evaluated both in stance and swing phases (p=0.0001). In addition, there was a decrease in the value of the normalized hip and total CCIs in both phases of gait (p<0.05). The results revealed changes in the neuromuscular mechanisms used by typical children to deal with the demands involved in the process of gait acquisition.