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Objective: To evaluate and compare the effects of conventional proprioceptive training and games with motion monitoring on plantar tactile sensitivity in older women., Methods: A randomized controlled clinical trial, with 50 older women randomized into three groups: conventional proprioception (n = 17), games with motion monitoring (n = 16), and the control (n = 17). They underwent 24 intervention sessions, three times a week, for eight weeks. The conventional proprioception group performed exercises involving gait, balance, and proprioception. The games performed by the motion monitoring group included exercises using the Xbox Kinect One video game from Microsoft ® . The evaluation of tactile pressure sensitivity was performed using Semmes-Weinstein monofilaments. Intragroup comparisons between the two paired samples were performed using paired Student's t -test or Wilcoxon test. Intergroup comparisons between the three independent samples were performed using the Kruskal-Wallis test and Dunn's post hoc test, with p ≤ 0.05., Results: The older women submitted to conventional games with motion monitoring training and showed improvement in plantar tactile sensitivity in the right and left feet. When comparing the intergroup results, the two training modalities obtained an improvement in the plantar tactile sensitivity of the older women when compared to the control group., Conclusions: We conclude that both training modalities may favor the improvement of plantar tactile sensitivity in older women, with no significant differences between conventional and virtual training.

In the body of research on the relationship between gesture and speech, some models propose they form an integrated system while others attribute gestures a compensatory role in communication. This study addresses the gesture-speech relationship by taking disfluency phenomena as a case study. Since it is part of a project aimed at designing virtual agents to be employed in museums, an analysis was performed on the communicative behavior of tourist guides. Results reveal that gesturing is more frequent during speech than pauses. Moreover, when comparing the types of gestures and types of pauses they co-occur with, non-communicative gestures (idles and manipulators) turn out to be more frequent than communicatively-meaningful gestures, which instead more often co-occur with speech. We discuss these findings as relevant for a theoretical model viewing speech and gesture as an integrated system., (© 2022. The Author(s), under exclusive licence to Marta Olivetti Belardinelli.)

An analytical method for the simultaneous determination of nine prohibited N -nitrosamines in cosmetic products is presented. N -nitrosamines are banned compounds in cosmetic products due to their harmful effects. Therefore, these compounds are not intentionally added to these products but, however, small amounts of them may be present due to unintentional causes, and thus sensitive methods for their analytical control are required. The proposed method is based on vortex-assisted dispersive liquid-liquid microextraction (VA-DLLME) to extract and preconcentrate the analytes, followed by gas chromatography-mass spectrometry (GC-MS) for their determination. The variables involved in the VA-DLLME process were optimized by using a Box-Behnken design and, due to the different polarity of the N -nitrosamines studied, several approaches for sample treatment were compared to achieve the best results. The method was successfully validated, showing a good linearity at least up to 20 ng mL -1 , enrichment factors from 2 to 100 depending on the target analyte, limits of detection and quantification at the low μg kg -1 level, and good repeatability values (<13%). Finally, the proposed analytical method was applied to the determination of N -nitrosamines in commercial cosmetic samples of different nature, avoiding the matrix effect by means of standard addition calibration. Significant amounts of some of the N -nitrosamines, even exceeding the established regulatory limit, were found in the samples. The resulting method is fast, simple, and affordable to carry out the quality control of cosmetic products to ensure consumer safety for most laboratories., Competing Interests: The authors declare that there are no conflicts to declare, they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

An analytical method for the determination of residual acrylamide in cosmetic products containing potential acrylamide-releasing ingredients is presented. The method is based on vortex-assisted reversed-phase dispersive liquid-liquid microextraction (VA-RP-DLLME) to extract and preconcentrate acrylamide by using water as extraction solvent taking advantage the highly polar behavior of this analyte, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for its determination. Under optimized conditions (5 mL toluene as supporting solvent, 50 µL of water as extraction solvent, 1 min for vortex extraction time) the method was properly validated obtaining good analytical features (linearity up to 20 ng mL -1 , method limits of detection and quantification of 0.51 and 1.69 ng g -1 , respectively, enrichment factor of 52, and good repeatability (RSD < 4.1%)). The proposed analytical method was applied to the determination of acrylamide in commercial samples that were weighed and dispersed in the minimum quantity of methanol (50 µL) by vortex stirring before applying the VA-RP-DLLME procedure. Through the pretreatment of the sample and the use of acrylamide-d 3 as surrogate, the matrix effect was overcome, obtaining good relative recovery values (88-108%). The proposed method has shown efficacy, simplicity, and speed, and it allows the determination of acrylamide at trace levels easily, which could make it very useful for companies in the quality control of cosmetic products containing potential acrylamide-releasing ingredients to fulfill the safety limits imposed by European Regulation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Human gait is a complex task resulting from the interaction of sensory perception, muscle force output, and sensory-motor integration, which declines with the aging process and impacts gait speed in older women., Research Question: What are the separate and combined impacts of sensory-motor factors on gait speed of older women?, Methods: Sixty healthy older women (69.3 ± 5.9 years) volunteered for this study. A previous screening using Pearson's correlation selected variables significantly correlated with gait speed: age, plantar tactile perception, lower limb explosive force, and mean velocity (MV) of the center of pressure (CoP). Simple and multivariate regression models were performed with selected variables. The magnitude of evidence was obtained using Bayesian inference, determining posterior probabilities based on our data., Results: Gait speed was negatively correlated with age and positively correlated with plantar tactile perception, MV (Romberg index), and lower limb explosive force. The coefficient of determination (R 2 ) varied between 0.06 for plantar tactile perception and 0.22 for explosive force (p < 0.05). The multivariate model, including age, MV (Romberg index), and lower limb explosive force, explained 44% (R 2 = 0.44) of the variance in gait speed, with a small standard error of estimate (0.14 m/s). Bayesian inference confirmed the good posterior probability of the model., Significance: Age, plantar tactile perception, MV (Romberg index), and lower limb explosive force impact gait speed, whereas the combination of the first three factors has an excellent posterior probability of predicting or affecting gait speed., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Purpose: This study aimed to compare heart rate variability (HRV) parameters obtained through symbolic analysis (SA), between older adults with and without hyperuricemia., Methods: This is a cross-sectional study including 202 community-dwelling old adults, which was clinically stratified as with or without hyperuricemia, according to the cutoff point of serum uric acid ≥ 6 mg/dL for women and ≥ 7 mg/dL for men. Successive RR intervals were recorded along 5 min and analyzed with SA method. 0 V%, 1 V% and 2 V% patterns were quantified and compared between groups. Comparisons were carried out through parametric or nonparametric tests, according to the data distribution characteristics, evaluated by Kolmogorov-Smirnov test. The significance level was set as p ≤ 0.05 for all statistical procedures., Results: The prevalence of hyperuricemia was 67.8 %, and the hyperuricemic older adults exhibited significant higher values for V0% and lower values for V2% parameters when compared to normouricemic older adults., Conclusion: These results suggesting a sympathovagal imbalance in hyperuricemic older adults, characterized by greater sympathetic predominance (0 V%) and lower vagal modulation (2 V%) at rest conditions., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Increasing perceived hand size with magnifying lenses improves tactile discrimination and induces changes in action performance. We previously demonstrated that motor skills (tested with grip force, finger tapping, and a reach to grasp tasks) improved when actions were performed with magnified compared to normal vision; twenty-eight percent of 25 participants with stroke exhibited significant improvement on a composite measure of motor performance with magnification as compared to a session without magnification., Methods: To investigate the potential implications of magnification of vision for motor rehabilitation, we recruited individuals with stroke from the original cohort who exhibited an improvement of at least 10% in grip force and/or finger tapping for a home training protocol. Six individuals with stroke completed a two-week home-based training program in which they performed a range of activities while looking at their hand magnified. Motor skills were measured before, immediately after, and two weeks after the training., Results: Five of the six participants showed an improvement on motor tasks when tested after the training. In two participants the improvement was evident immediately after the training and persisted in time, while it occurred at two-weeks post-training in the other participants. These results suggest that the magnification of vision is a potential tool for the rehabilitation of post-stroke motor deficits., Competing Interests: The authors declare there are no competing interests.

Purpose: The aims of this study were to compare the autonomic heart control parameters from sarcopenic and non-sarcopenic community-dwelling elders., Methods: This is a cross-sectional study including 76 community-dwelling old adults, which was clinically stratified as sarcopenic or non-sarcopenic, according to the current recommendations. They were submitted to 5-min recordings of successive RR intervals. The analysis of the RR intervals variability was carried out in time (mean RR, RMSSD, pNN50, SDNN and triangular index) and frequency domains (LFnu, HFnu and LF/HF ratio), and with nonlinear methods (SD1, SD2, and D 2 ). The parameters of autonomic heart rate modulation (AHRM) were adjusted for potential confounders: sex, diabetes, beta-blockers use, cardiovascular disease, body mass index and physical activity level, smoking habit. Normality of the data was tested by Kolmogorov-Smirnov test and, since most variables did not exhibit a normal distribution the Mann-Whitney test was used to compare the parameters of AHRM. The significance level was set as p ≤ 0.05 and all statistical procedures were performed with SPSS ® ., Results: Adjusted parameters of AHRM obtained from time domain and nonlinear methods were significantly different between sarcopenic and non-sarcopenic elders (p < 0.05), while parameters obtained from frequency domain analysis did not were different between groups (p > 0.05)., Conclusion: Sarcopenic old adults exhibited lower parasympathetic-associated modulation, suggesting a poor cardioprotection associated to this condition., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Introduction: The aging process leads to functional decline of sensorial organs, muscle mass and strength, as well as the sensorimotor integration, culminating in age-associated postural control impairments. The purpose of this study was to compare the balance, the sensorial integration process and the lower limb strength among three old aged groups., Methods: Eighty-one community-dwelling healthy old people (58% women), assigned into three age groups [60-69 years (n=30), 70-79 years (n=40), and ≥80 years (n=11)], participated in this study. All participants were submitted to anthropometric and stabilometric evaluation, and carried out a Chair stand test. Stabilometric parameters obtained from time [amplitude displacement of center of pressure (CoP)] and frequency (oscillations of CoP at sub 0.3 Hz and 1-3 Hz bands) domain analysis were used as the indicators of balance performance and sensorial integration, respectively., Results: Our results revealed that the CoP amplitude displacement was significantly greater in the older aged group, without differences in spectral bands, while the performance in the Chair stand test was smaller in the older aged group., Conclusion: These data indicate that the age-associated postural control impairment is explained by the lower limb strength declines, but not by the age-associated changes in sensorial integration., Level of Evidence: III., Competing Interests: Conflict of interest The Authors have no conflicts of interest related to this study.

The analysis of explosive force, through rate of force development (RFD) and contractile impulse (CI), from handgrip strength data seems to be useful and promising information to study the aging of musculoskeletal system and health status. We aimed to test the hypothesis that, in elderly women, the handgrip explosive force could be better associated to the functional mobility than maximum handgrip strength. Handgrip strength and the performance of Timed Up & Go Test (TUG) were measured from sixty-five community-dwelling healthy elderly women. The average slope of the moment-time curve (Δ moment/Δ time) over the time interval of 0-200 ms relative to the onset of contraction was calculated to provide the RFD and CI. The highest strength achieved during the isometric contraction was used as maximum handgrip strength. Pearson correlations were used to assess the strength of the relationship between the handgrip strength parameters (Maximum strength and explosive force from 0-200 ms) and TUG test performance from older women. The correlation analysis showed that the TUG test performance was inversely correlated to the handgrip strength parameters, with better relationship with explosive force parameters. The handgrip explosive force seems to be a promising predictor of functional mobility of elderly women, since it showed a better relationship with functional mobility than maximum handgrip strength.

The aging process causes many changes in muscle strength, and analysis of explosive force from handgrip strength seems to be useful and promising in studying the aging musculoskeletal system. Therefore, the purpose of this study was to investigate if explosive force parameters [rate of force development (RFD) and contractile impulse (CI) over the time interval of 0-200 ms from the onset of contraction] during handgrip efforts decline differently than maximum handgrip strength with increasing age. Twenty healthy young women (20-27 years) and 65 healthy elderly women, assigned into three age groups (50-64, 65-74, and 75-86 years), participated in this study. All participants performed two maximal grip attempts. Handgrip data were recorded as force-time curves, peak force, and explosive force parameters. Our results revealed that peak force decreased significantly (p < 0.05) for those who are 65 years old, while explosive force parameters decreased significantly (p < 0.05) for those aged 50 years. These data indicate that the decline in explosive grip force-generating capacity may begin earlier (i.e., for those aged 50 years old) than peak force during the aging process. Our findings suggest that the aging process reduces the explosive grip force-generating capacity before affecting peak force.

The goal of this paper was to investigate the amplitude and sub-100 Hz frequency content of surface electromyography (EMG) signals obtained from agonist, antagonist and synergist muscles during a heel-raise task sustained to failure. Twenty-two healthy adults, 14 men and 8 women participated in the study. Surface EMG data from the raising and lowering phases of the movement were studied in the time (EMG amplitude) and frequency (wavelet transform) domains. For the raising phase, we found a significant increase in the EMG amplitude of all muscles studied throughout the task (P < 0.02); however, for the lowering phase, we found a decrease in overall muscle activation for the medial gastrocnemius and tibialis anterior. Additionally, we found higher 13-30 and 30-50 Hz normalized power during the raising phase for the triceps surae prior to task failure and at task failure compared with the beginning and midway of the task (P < 0.05); during the lowering phase, however, we found higher normalized power from 30 to 50 Hz for the triceps surae (P < 0.01) and higher 13-30 Hz normalized power for the tibialis anterior (P < 0.01) at task failure compared with the beginning and midway of the task. Finally, we showed that a dynamic task performed until failure can induce different activation strategies for agonist, antagonist and synergist muscles, and that the frequency content below 100 Hz contains useful information about the neural activation of these muscles in relation to task failure that is not evident from the EMG amplitude.

A genetic paradox exists in invasion biology: how do introduced populations, whose genetic variation has probably been depleted by population bottlenecks, persist and adapt to new conditions? Lessons from conservation genetics show that reduced genetic variation due to genetic drift and founder effects limits the ability of a population to adapt, and small population size increases the risk of extinction. Nonetheless, many introduced species experiencing these same conditions during initial introductions persist, expand their ranges, evolve rapidly and become invasive. To address this issue, we studied the brown anole, a worldwide invasive lizard. Genetic analyses indicate that at least eight introductions have occurred in Florida from across this lizard's native range, blending genetic variation from different geographic source populations and producing populations that contain substantially more, not less, genetic variation than native populations. Moreover, recently introduced brown anole populations around the world originate from Florida, and some have maintained these elevated levels of genetic variation. Here we show that one key to invasion success may be the occurrence of multiple introductions that transform among-population variation in native ranges to within-population variation in introduced areas. Furthermore, these genetically variable populations may be particularly potent sources for introductions elsewhere. The growing problem of invasive species introductions brings considerable economic and biological costs. If these costs are to be mitigated, a greater understanding of the causes, progression and consequences of biological invasions is needed.

Niche conservatism--the tendency for closely related species to be ecologically similar--is widespread. However, most studies compare closely related taxa that occur in allopatry; in sympatry, the stabilizing forces that promote niche conservatism, and thus inhibit niche shifts, may be countered by natural selection favouring ecological divergence to minimize the intensity of interspecific interactions. Consequently, the relative importance of niche conservatism versus niche divergence in determining community structure has received little attention. Here, we examine a tropical lizard community in which species have a long evolutionary history of ecological interaction. We find that evolutionary divergence overcomes niche conservatism: closely related species are no more ecologically similar than expected by random divergence and some distantly related species are ecologically similar, leading to a community in which the relationship between ecological similarity and phylogenetic relatedness is very weak. Despite this lack of niche conservatism, the ecological structuring of the community has a phylogenetic component: niche complementarity only occurs among distantly related species, which suggests that the strength of ecological interactions among species may be related to phylogeny, but it is not necessarily the most closely related species that interact most strongly.

The activation of amygdaloid nuclei, the ventral perirhinal cortex (vPRh), and several other brain areas in the rat during the acquisition and expression of olfactory fear conditioning was assessed through Fos immunocytochemistry in 3 separate experiments. The results of Experiment 1 suggest that olfactory and somatosensory inputs may functionally converge in the anterior region ot the medial nucleus (aMe). The results of Experiment 2 indicate that the aMe exhibited significantly greater Fos-like immunoreactivity (FLI) in subjects acquiring conditioned stimulus-unconditioned stimulus associations than in those presented with the same olfactory and somatosensory stimuli in a manner that precluded acquisition. The results of Experiment 3 indicate that the vPRh appeared to exhibit learning-related increases in FLI during the expression of previously acquired associations. Collectively, these data suggest that the aMe and vPRh may be critically involved in different aspects of olfactory fear conditioning.

The vagaries of history lead to the prediction that repeated instances of evolutionary diversification will lead to disparate outcomes even if starting conditions are similar. We tested this proposition by examining the evolutionary radiation of Anolis lizards on the four islands of the Greater Antilles. Morphometric analyses indicate that the same set of habitat specialists, termed ecomorphs, occurs on all four islands. Although these similar assemblages could result from a single evolutionary origin of each ecomorph, followed by dispersal or vicariance, phylogenetic analysis indicates that the ecomorphs originated independently on each island. Thus, adaptive radiation in similar environments can overcome historical contingencies to produce strikingly similar evolutionary outcomes.