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Aim: The centre–periphery hypothesis (CPH) sustains that peripheral populations are subjected to harsher environmental conditions, which reduces demographic performance manifested, among others, by lower abundance, higher inbreeding and higher developmental instability. However, range centrality/peripherality is not necessarily a good proxy for environmental suitability since geographical distributions are often irregular in shape, barriers may limit dispersal towards suitable areas, and ancestral range shifts may have occurred unevenly in each direction. We evaluated predictions of the CPH for populations of the Neotropical lizard Notomabuya frenata by modelling the effects of environmental suitability and geographical centrality/peripherality upon demographic performance. Location: Brazilian Cerrado. Taxon: Notomabuya frenata (Squamata, Scincidae). Methods: We used populational values of body size, body mass, body condition, tail autotomy and fluctuating asymmetry (FA; a proxy of developmental instability) to estimate demographic performance. Then, we built correlative models to estimate environmental suitability for each sampled population. Finally, we used hierarchical Bayesian models based on a combination of stochastic partial differential equations and integrated nested Laplace approximations to model the relationships between demographic performance and predictor variables (geographical centrality/peripherality and environmental suitability) and make predictions across the geographical distribution of N. frenata. Results: Generalized boosting produced the best environmental suitability models. The total suitability area spanned more than 4 million km2 in cis‐Andean South America. All scalation counts presented some degree of asymmetry. Only three response variables—all related to FA—responded significantly to predictor changes. Contrary to the predictions of the CPH, one scalation count presented higher asymmetry closer to the range center and another in more suitable environments. Peripherality did not significantly influence any of the response variables. Main Conclusions: Populations may respond differently to geographical centrality/peripherality and environmental suitability, as these characteristics do not necessarily coincide. Studies testing the CPH should ideally incorporate these different predictors of demographic performance. [ABSTRACT FROM AUTHOR]

The aim of this paper was to evaluate the effect of high energy ultrasound on the bioaccessibility of bioactive compounds from açaí (Euterpe precatoria) and buriti (Mauritia flexuosa) juices. Five levels of energy density (0, 0.9, 1.8, 2.7 and 3.6 J.cm -3 ), as well as their effects on the bioactive compounds were evaluated. Ultrasound did not significantly influence pH, titratable acidity and soluble solids. However, it affected the color attributes of juices by increasing brightness and color variation. The concentration of bioactive compounds (anthocyanins and carotenoids) and antioxidants increased with increasing ultrasound energy density, which was confirmed by Principal Component Analysis (PCA). Fatty acids increased up to 2.7 J.cm -3 and were reduced when higher energy was employed on the ultrasound process. Ultrasound allowed the release of new aromatic substances. For this reason, the ultrasound technology can be considered an alternative pre-treatment for fruit juices, improving the bioaccessibility and concentration of bioactive compounds., 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 © 2020 Elsevier B.V. All rights reserved.)