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BACKGROUND: The COVID-19 pandemic has affected the physical behaviours of office workers worldwide, but studies comparing physical behaviours between countries with similar restrictions policies are rare. This study aimed to document and compare the 24-hour time-use compositions of physical behaviours among Brazilian and Swedish office workers on working and non-working days during the pandemic. METHODS: Physical behaviours were monitored over 7 days using thigh-worn accelerometers in 73 Brazilian and 202 Swedish workers. Daily time-use compositions were exhaustively described in terms of sedentary behaviour (SED) in short (< 30 min) and long (≥30 min) bouts, light physical activity (LPA), moderate-to-vigorous physical activity (MVPA), and time-in-bed. We examined differences between countries using MANOVA on data processed according to compositional data analysis. As Swedish workers had the possibility to do hybrid work, we conducted a set of sensitivity analyses including only data from days when Swedish workers worked from home. RESULTS: During working days, Brazilian office workers spent more time SED in short (294 min) and long (478 min) bouts and less time in LPA (156 min) and MVPA (50 min) than Swedish workers (274, 367, 256 and 85 min, respectively). Time spent in bed was similar in both groups. Similar differences between Brazilians and Swedes were observed on non-working days, while workers were, in general, less sedentary, more active and spent more time-in-bed than during working days. The MANOVA showed that Brazilians and Swedes differed significantly in behaviours during working (p <  0.001, ηp2 = 0.36) and non-working days (p <  0.001, ηp2 = 0.20). Brazilian workers spent significantly more time in SED relative to being active, less time in short relative to long bouts in SED, and more time in LPA relative to MVPA, both during workdays and non-workdays. Sensitivity analyses only on data from days when participants worked from home showed similar results. CONCLUSIONS: During the COVID-19 pandemic Brazilian office workers were more sedentary and less active than Swedish workers, both during working and non-working days. Whether this relates to the perception or interpretation of restrictions being different or to differences present even before the pandemic is not clear, and we encourage further research to resolve this important issue.

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Aging is a biological process, which is usually associated with health-related problems, which are related to some behaviours, such as those related to movement and eating habits. So, the purpose of the present study was to identify the clustering of behavioural and eating habits related to non-communicable disease in Brazilian elderly, and to estimate the association of these profiles with overweight/obesity, hypertension, and diabetes. This is a cross-sectional based-population study, which sample comes from the VIGITEL 2019 survey. The sample comprised 23,327 subjects (16,295 women), mean age of 71 years. Sociodemographic and anthropometric data (i.e., age, sex, body weight, and body height), health-related information (i.e., eating habits, physical activity and sedentary behaviour, and alcohol consumption), health status and morbidity (diabetes and hypertension) were self-reported. Latent Classes Analysis, and binary logistic regression were performed, considering p<0.05. Results showed that two different classes were identified. Those called as "TV viewer, but no unhealthy diet" presented more chances to have hypertension (OR: 1.213; 95%CI: 1.064-1.382) and diabetes (OR: 1.365; 95%CI: 1.157-1.610), when compared to their peers called as "healthy diet and active". Age, educational level, and sex were associated with hypertension and diabetes. In conclusion, a better health clustered-behaviour was associated with better disease outcomes in Brazilian elderly population.

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Adherence to healthy behaviours promotes several health benefits in preschool children, including executive function (EF). Recently, the predictive power of the 24-hour movement behaviour (24 h MB) composition on health outcomes has been evidenced; however, its relationship with EF in preschoolers is unknown. Thus, the present study had two objectives: (1) to analyse the associations between the 24 h MB composition and EF of preschoolers; and (2) to investigate the theoretical changes in EF when time in different movement behaviours is reallocated. This cross-sectional study was carried out with 123 preschoolers (3-5 years old) of low socioeconomic status. Physical activity (PA) and sedentary behaviour were assessed using an accelerometer for 7 days, sleep time was obtained through interviews with parents, and EF was measured using the Early Tool Box battery. To verify the association between 24 h MB and EF, compositional data analysis was used, and for time reallocation, compositional isotemporal substitution analysis was utilized. It was observed that the 24 h MB composition was positively associated with EF (p < .0001; R² = 0.34), and that reallocating 5, 10, 15 or 20 min of the time spent on sleep and light PA to moderate-to-vigorous PA, respectively, was associated with significant improvements in EF (p < .05). These findings provide hitherto unseen insight into the relationship between 24 h MB and EF in preschool children, and warrants consideration for researchers and practitioners seeking to improve EF and PA in preschool children.

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Animals do not move all the time but alternate the period of actual movement (foraging) with periods of rest (e.g. eating or sleeping). Although the existence of rest times is widely acknowledged in the literature and has even become a focus of increased attention recently, the theoretical approaches to describe animal movement by calculating the dispersal kernel and/or the mean squared displacement (MSD) rarely take rests into account. In this study, we aim to bridge this gap. We consider a composite stochastic process where the periods of active dispersal or 'bouts' (described by a certain baseline probability density function (pdf) of animal dispersal) alternate with periods of immobility. For this process, we derive a general equation that determines the pdf of this composite movement. The equation is analysed in detail in two special but important cases such as the standard Brownian motion described by a Gaussian kernel and the Levy flight described by a Cauchy distribution. For the Brownian motion, we show that in the large-time asymptotics the effect of rests results in a rescaling of the diffusion coefficient. The movement occurs as a subdiffusive transition between the two diffusive asymptotics. Interestingly, the Levy flight case shows similar properties, which indicates a certain universality of our findings.

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Invasion of alien species is one of the major threats for natural community structures, potentially leading to high economic and environmental costs. In this work, we study through a reaction-diffusion model the dynamics of an invasion in a heterogeneous environment and in the presence of a strong Allee effect. We model space as an infinite landscape consisting of periodically alternating favourable and unfavourable patches. In addition, we consider that at the interface between patch types individuals may show preference for more favourable regions. Using homogenization techniques and a classical result for spread with Allee effect in homogeneous landscapes, we derive approximate expressions for the spread speed. When compared with numerical simulations, these expressions prove to be very accurate even beyond the expected small-scale heterogeneity limit of homogenization. We demonstrate how rates of spatial spread depend on demographic and movement parameters as well as on the landscape properties.

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