Sit less and move more! A cross-sectional study of the associations between physical activity and sedentary behaviors with inhibitory control in Brazilian adults

OBJECTIVE

To investigate the independent and joint associations between sedentary behaviors (SB) and physical activity (PA) with inhibitory control (IC) in adults.

METHODS

A total of 111 participants (median age = 30 years; 60% women), completed the Stroop Color-Words test to assess IC. They also wore accelerometers for seven days to measure SB, light PA, moderate-to-vigorous PA (MVPA), and daily steps. We previously set cutoff points for SB and PA measurements and tested them to determine their association with IC. All analyses were adjusted for potential confounding factors including age, gender, post-secondary education, income, body mass index, and accelerometer wear time.

RESULTS

Low SB, high MVPA, and high daily steps were independently associated with a better IC compared to their respective counterparts. Adults with low levels of SB and light PA demonstrated better IC performance (β = -227.67, 95%CI = -434.14 to -21.20) compared to those with high SB and low light PA. Conversely, individuals with high SB and high light PA exhibited worse performance (β = 126.80, 95%CI = 2.11 to 251.50) than those in the high SB and low light PA group. Furthermore, the joint association of low SB with high MVPA (β = -491.12, 95%CI = -689.23 to -293.01) or low SB with high daily steps (β = -254.29, 95%CI = -416.41 to -92.16) demonstrated better IC performance compared to those with high SB and low MVPA or low daily steps.

CONCLUSION

Our findings highlight independent and joint associations between low SB, high MVPA, and high daily steps with enhanced IC in adults.

How to account for behavioral states in step-selection analysis: a model comparison

Step-selection models are widely used to study animals' fine-scale habitat selection based on movement data. Resource preferences and movement patterns, however, often depend on the animal's unobserved behavioral states, such as resting or foraging. As this is ignored in standard (integrated) step-selection analyses (SSA, iSSA), different approaches have emerged to account for such states in the analysis. The performance of these approaches and the consequences of ignoring the states in step-selection analysis, however, have rarely been quantified. We evaluate the recent idea of combining iSSAs with hidden Markov models (HMMs), which allows for a joint estimation of the unobserved behavioral states and the associated state-dependent habitat selection. Besides theoretical considerations, we use an extensive simulation study and a case study on fine-scale interactions of simultaneously tracked bank voles (Myodes glareolus) to compare this HMM-iSSA empirically to both the standard and a widely used classification-based iSSA (i.e., a two-step approach based on a separate prior state classification). Moreover, to facilitate its use, we implemented the basic HMM-iSSA approach in the R package HMMiSSA available on GitHub.

Detecting major depressive disorder presence using passively-collected wearable movement data in a nationally-representative sample

Major Depressive Disorder (MDD) is a heterogeneous disorder, resulting in challenges with early detection. However, changes in sleep and movement patterns may help improve detection. Thus, this study aimed to explore the utility of wrist-worn actigraphy data in combination with machine learning (ML) and deep learning techniques to detect MDD using a commonly used screening method: Patient Health Questionnaire-9 (PHQ-9). Participants (N = 8,378; MDD Screening = 766 participants) completed the and wore Actigraph GT3X+ for one week as part of the National Health and Nutrition Examination Survey (NHANES). Leveraging minute-level, actigraphy data, we evaluated the efficacy of two commonly used ML approaches and identified actigraphy-derived biomarkers indicative of MDD. We employed two ML modeling strategies: (1) a traditional ML approach with theory-driven feature derivation, and (2) a deep learning Convolutional Neural Network (CNN) approach, coupled with gramian angular field transformation. Findings revealed movement-related features to be the most influential in the traditional ML approach and nighttime movement to be the most influential in the CNN approach for detecting MDD. Using a large, nationally-representative sample, this study highlights the potential of using passively-collected, actigraphy data for understanding MDD to better improve diagnosing and treating MDD.

Associations between meeting 24-hour movement guidelines and myopia among school-aged children: A cross-sectional study

BACKGROUND

The Canadian 24-hour movement behavior (24-HMB) guidelines recommend an adequate level of physical activity (PA), a limited amount of screen time (ST), and a sufficient sleep duration (SLP) to promote the healthy development of children. Although the positive effects of adhering to the 24-HMB guidelines have been established for several health parameters, less is known about how adherence to the 24-HMB guidelines relates to the myopia risk (i.e., inability to see distant objects properly). Thus, this study investigated associations between meeting 24-HMB guidelines and myopia risk in school-aged children.

METHOD

Using a questionnaire survey, this cross-sectional study was conducted among parents of school-aged children (5-13 years) in China from 15th September to 15th October 2022, with a total of 1423 respondents with complete data for analysis. Parents reported their child's time spent in moderate-to-vigorous-intensity physical activity (MVPA), SLP, and ST. Multiple logistic regression analyses were performed to examine the associations between measures of PA, ST, and SLP alone and in combination, and the occurrence of myopia.

RESULTS

A relatively low percentage of the children being included in the current study (4.92%) met all 24-HMB guidelines, while 32.46% had myopia. Girls had a significantly higher risk of myopia compared to boys (OR = 1.3, 1.002 to 1.68, p = 0.049). Children of parents without myopia had a lower risk of myopia (OR = 0.45, 0.34-0.59, p < 0.001). Children who lived in urban areas (OR = 1.83, 95% CI 1.33 to 2.52, p < 0.001) or towns (OR = 1.60, 1.03 to 2.47, p = 0.04) had a significantly higher risk of myopia compared to those living in rural areas. Meeting SLP guidelines (OR = 0.50, 95% CI 0.31 to 0.82, p < 0.01), meeting ST + SLP guidelines (OR = 0.47, 95% CI 0.32-0.69, <0.001), and meeting all three guidelines were associated with significantly lower risk of myopia (OR = 0.40, 95% CI 0.20-0.82, p = 0.01). Meeting more 24-HMB guidelines was associated with a reduced risk of myopia.

CONCLUSIONS

Our data suggest that adhering to SLP, ST + SLP, and ST + SLP + PA guidelines is associated with the risk of myopia. Future research investigating dose-response associations, and potential mechanisms, is necessary to achieve a more nuanced understanding of the observed associations.

Change-point models for identifying behavioral transitions in wild animals

Animal behavior can be difficult, time-consuming, and costly to observe in the field directly. Innovative modeling methods, such as hidden Markov models (HMMs), allow researchers to infer unobserved animal behaviors from movement data, and implementations often assume that transitions between states occur multiple times. However, some behavioral shifts of interest, such as parturition, migration initiation, and juvenile dispersal, may only occur once during an observation period, and HMMs may not be the best approach to identify these changes. We present two change-point models for identifying single transitions in movement behavior: a location-based change-point model and a movement metric-based change-point model. We first conducted a simulation study to determine the ability of these models to detect a behavioral transition given different amounts of data and the degree of behavioral shifts. We then applied our models to two ungulate species in central Pennsylvania that were fitted with global positioning system collars and vaginal implant transmitters to test hypotheses related to parturition behavior. We fit these models in a Bayesian framework and directly compared the ability of each model to describe the parturition behavior across species. Our simulation study demonstrated that successful change point estimation using either model was possible given at least 12 h of post-change observations and 15 min fix interval. However, our models received mixed support among deer and elk in Pennsylvania due to behavioral variation between species and among individuals. Our results demonstrate that when the behavior follows the dynamics proposed by the two models, researchers can identify the timing of a behavioral change. Although we refer to detecting parturition events, our results can be applied to any behavior that results in a single change in time.

Exploration of the effect and potential mechanism of quercetin in repairing spinal cord injury based on network pharmacology and in vivo experimental verification

Spinal cord injury (SCI) is a highly complex neurological disease, but there is no effective repair method. Quercetin is a flavonol drug and has a variety of biological activities, such as scavenging oxygen free radicals in the body to resist oxidation, inhibiting inflammation, and so on. In this study, quercetin was firstly demonstrated to reduce tissue damage, promote neuron survival and repair motor function after SCI in rats through in vivo experiments. Then, 293 potential targets of quercetin repair for SCI were predicted by network pharmacology. GO analysis revealed that the biological processes of potential targets focused mainly on signal transduction, negative regulation of the apoptotic process, protein phosphorylation, drug response, and so on. Similarly, KEGG analysis suggested that these potential targets were involved in cell growth regulation, differentiation, apoptosis, and a few metabolic pathways. PPI network analysis predicted that the key genes were EP300, CREBBP, SRC, HSP90AA1, TP53, PIK3R1, EGFR, ESR1, and CBL. Further, the molecular docking showed that quercetin binds well with these proteins. Finally, RT-qPCR and Western blotting experiments verified that quercetin downregulated the expression levels of PIK3R1 and EGFR. It is suggested that quercetin can repair SCI in rats through PI3K-AKT signaling pathway and EGFR/MAPK pathway, which may provide a new theoretical basis for the repair of spinal cord injury.

Physical Literacy for Communities (PL4C): physical literacy, physical activity and associations with wellbeing

BACKGROUND

Physical literacy (PL) is considered an important determinant of children's physical activity through which health benefits may be derived. The purpose of this study is to describe a sample of Canadian children's baseline levels of PL and movement behaviors, and explore whether the associations between PL and their mental wellbeing, if any, are mediated by moderate-to-vigorous physical activity (MVPA).

METHODS

All grade two children in 14 elementary schools in the West Vancouver School District, Canada were invited to participate in a two-year longitudinal project. PL was assessed through PLAYfun and PLAYself tools. Physical activity was measured by wrist-worn accelerometers (GT3X + BT) for seven days. Children's mental well-being was assessed using the Strengths and Difficulties Questionnaire (SDQ). A score of total difficulties was aggregated for internalizing and externalizing problems.

RESULTS

A total of 355 children aged 7-9 (183 boys, 166 girls, 6 non-binary) participated with 258 children providing valid accelerometer data. Children exhibited an average of 111.1 min of MVPA per day, with 97.3% meeting the physical activity guidelines. Approximately 43% (108/250) of participants were meeting the Canadian 24-h movement guidelines. Children were at an 'emerging' level of overall physical competence (45.8 ± 5.6) and reported a mean score of 68.9 (SD = 12.3) for self-perceived PL, with no significant differences between boys and girls. PL was significantly associated with MVPA (r = .27) and all SDQ variables (rs = -.26-.13) except for externalizing problems. Mediation analyses showed PL was negatively associated with internalizing problems and total difficulties when the association with MVPA was considered. However, the mediating role of MVPA was found only between PL and internalizing problems, β = -.06, 95%CI [-.12, -.01].

CONCLUSIONS

Although most of our sample was physically active and showed higher adherence to 24-H movement guidelines than comparable population data, the motor competence and self-perceived PL of our sample were similar to those of previous studies. PL has an independent association with children's internalizing problems and total difficulties. Ongoing assessment will investigate the relationships between PL and children's mental health from a longitudinal perspective.

Characteristics of tummy time and dose-response relationships with development in infants

This study aimed to examine change in tummy time patterns and preferences in the first 6 months of life, as well as dose-response relationships between tummy time duration and development at 2, 4, and 6 months. Participants were parents of infants from the Early Movers project in Edmonton, Canada (baseline: n = 411). At 2, 4, and 6 months, infant tummy time duration and preference (i.e., 1 = really likes to 5 = really dislikes) and development (i.e., Ages & Stages Questionnaire (ASQ-3) communication, fine motor, gross motor, problem-solving, personal-social) were measured by a parental questionnaire. In a subsample (n = 127), tummy time patterns (i.e., bout frequency, mean and median bout length) were measured using a 3-day time-use diary. Tummy time bout frequency, bout length, and preference significantly increased over time. Linear dose-response relationships between tummy time duration and development outcomes were observed at 4 (gross motor) and 6 months (all development outcomes). Moreover, at 2 months, 30-44 min/day of tummy time was associated with a higher total development score (vs. < 15 min/day; B = 11.14; 95%CI: 1.60, 20.68). At 6 months, 61-120 min/day (vs. < 30 min/day; B = 27.12; 95%CI: 11.93, 42.32) and > 120 min/day (vs. < 30 min/day; B = 33.80; 95%CI: 18.90, 48.70) of tummy time were associated with higher total development scores. Differences in threshold doses between some developmental outcomes were observed. Conclusion: In the first 6 months of life, increases were observed in tummy time preference as well as tummy time bout frequent and length. This finding may explain why the optimal amount of tummy time needed for more advanced development appeared to increase with age. What is Known: • Tummy time is a type of physical activity in infancy. International and national guidelines recommend at least 30 minutes of tummy time per day for infants who are not yet mobile. What is New: • In the first six months of life, preference for tummy time as well as tummy time bout frequency and length increased. • Tummy time duration had dose-response associations with several development outcomes, and the optimal amount of tummy time needed for more advanced development appeared to increase with age.

Accelerometer-Based Physical Activity, Sedentary Time, and BMI among Preschoolers in Puerto Rico

OBJECTIVE

A minimum of 3-h/day of any intensity physical activity (PA) has been recommended for preschoolers. No previous study has documented accelerometer-based PA and sedentary time (ST) among Hispanic preschoolers in Puerto Rico, a population with high obesity and low PA prevalence. The purpose of this study was to describe and compare total, weekdays (during- and out-of-preschool) and weekend PA and ST, and test associations with body mass index (BMI).

METHODS

A group of 3-5-year-old preschoolers (9 boys,13 girls) completed height and weight measurements, and wore an accelerometer during 7-days. Shapiro-Wilk, Mann-Whitney U test and Spearman correlations were used to test for normality, sex differences and associations, respectively.

RESULTS

No sex differences were observed for BMI, weekdays and weekends PA and ST. Light to vigorous intensity PA (LVPA=3.2±0.6 h/day) and moderate to vigorous intensity PA (MVPA=80.4±21.7 min/day) were within guidelines only on weekdays. LVPA occupied 21.3% (15.4±3.7 min/h), MVPA 9.5% (6.6±2.3 min/h), and ST 65.3% (4.8±0.4 h/day) of preschool time. Boys had higher MVPA than girls only during-preschool time. BMI indicative of overweight-obesity was identified in 36.3%, and BMI directly correlated with total ST and inversely correlated with LVPA.

CONCLUSION

Total and during-preschool LVPA and ST, and their association with BMI highlight the need for interventions to promote PA and reduce ST, particularly during-preschool time.

AMPK regulates behavior and physiological plasticity of Haliotis discus hannai under different spectral compositions

In natural environments, the spectral composition of incident light is often subject to drastic changes due to the abundance of suspended particles, floating animals, and plants in coastal waters. In this study, after four months of culturing under blue light (NB), orange light (NY), dark environment (ND), and natural light (NN), the shell length and weight-specific growth rate in Pacific abalone, Haliotis discus hannai, were ranked in the following order: NY > NN > ND > NB. To understand the growth differences in abalone under these different light environments, we first performed 24-h video monitoring and found that the cumulative movement distance and duration were lowest in group NB, whereas the cumulative movement distance and duration were significantly higher in group ND than in any other group (P < 0.05). In group NB, the time spent hidden underneath the attachment substrate accounted for 81% of the resting time, but this ratio was lowest in group ND, at only 37% (P < 0.05). Next, LC-MS metabolomics identified 201 and 105 metabolites in NB vs. NN, ND vs. NN, and NY vs. NN under the positive and negative ion modes, respectively. According to the fold changes and annotations for differential metabolites in the KEGG enrichment pathways, adenosine, NAD⁺, cGMP, and arachidonic acid were used as differential metabolism markers, and the AMPK signaling pathway was enriched in every comparison group, and thus investigated further. The gene sequences of three subtypes of AMPK were obtained by cloning and we found that the expression levels of AMPKα and AMPKγ, and the AMP content were significantly higher in group NB than in any other group (P < 0.05). In addition, the ATP contents and adenylate energy charge values were ranked in the following order: NY > NN > ND > NB. According to in situ hybridization analysis, the three subtype genes were widely expressed in the hepatopancreas. Finally, the contents of many lipid metabolites differed significantly among groups and the expression levels of the triglyceride hydrolysis-related gene hormone sensitive lipase and fatty acid oxidation-related gene carnitine palmitoyltransferase 1 were higher in groups ND and NB than in groups NN and NY according to fluorescence quantification PCR (P < 0.05). The expression levels of fatty acid synthase and acetyl-CoA carboxylase were significantly lower in groups ND and NB than in groups NN and NY (P < 0.05). These findings indicated that differences in the spectral composition of incident light could reshape the behavior and physiological metabolism in abalone by influencing the "energy switch" AMPK, thereby providing some insights into the mechanisms that allow nocturnal marine organisms to adapt to different lighting environments.

Meeting the 24-h movement guidelines and health-related outcomes among youth with autism spectrum disorder: a seven-country observational study

BACKGROUND

Meeting daily guidelines for physical activity, screen time, and sleep duration is associated with a host of health indicators for youth. In this cross-sectional observational study, we investigated the associations between adherence to the movement guidelines and health-related outcomes among youth with autism spectrum disorder (ASD).

METHODS

Parents of youth with ASD (10-17 years) from seven countries and regions were invited to provide online proxy-reports for child's movement behaviors (i.e., physical activity, sleep and screen time), and health-related outcomes (i.e., body mass index [BMI], general health, and quality of life). A series of multiple linear regression analyses were used to examine the associations between meeting movement guidelines and health-related outcomes, adjusted for covariates.

RESULTS

The final sample consisted of 1165 youth with ASD. Compared with youth meeting all three guidelines, a higher BMI z-score was observed in those who met no guidelines (B = 0.62, P = 0.04), "sedentary time only" (B = 0.60, P = 0.047), and "physical activity plus sleep only" (B = 0.85, P = 0.04). Compared with meeting all three guidelines, meeting no guidelines was associated with poorer general health (B = - 0.46, P = 0.02). Further, compared with youth meeting all three guidelines, a lower quality of life score was observed in those who met no guidelines (B = - 0.47, P = 0.02) and "physical activity only" (B = - 0.62, P = 0.03). Lastly, there were dose-response associations between the number of guidelines met and all three health-related outcomes (all P_trend < 0.05).

CONCLUSIONS

In conclusion, meeting more 24-h movement guidelines was generally associated with more favorable health-related outcomes in youth with ASD. The low level of adherence to all three guidelines (2.0%) suggests the urgent need to promote the adoption of all the guidelines in this group.

Movement behavior patterns composition remains stable, but individuals change their movement behavior pattern over time in people with a first-ever stroke

BACKGROUND

Movement behaviors (i.e., physical activity levels, sedentary behavior) in people with stroke are not self-contained but cluster in patterns. Recent research identified three commonly distinct movement behavior patterns in people with stroke. However, it remains unknown if movement behavior patterns remain stable and if individuals change in movement behavior pattern over time.

OBJECTIVES

1) To investigate the stability of the composition of movement behavior patterns over time, and 2) determine if individuals change their movement behavior resulting in allocation to another movement behavior pattern within the first two years after discharge to home in people with a first-ever stroke.

METHODS

Accelerometer data of 200 people with stroke of the RISE-cohort study were analyzed. Ten movement behavior variables were compressed using Principal Componence Analysis and K-means clustering was used to identify movement behavior patterns at three weeks, six months, one year, and two years after home discharge. The stability of the components within movement behavior patterns was investigated. Frequencies of individuals' movement behavior pattern and changes in movement behavior pattern allocation were objectified.

RESULTS

The composition of the movement behavior patterns at discharge did not change over time. At baseline, there were 22% sedentary exercisers (active/sedentary), 45% sedentary movers (inactive/sedentary) and 33% sedentary prolongers (inactive/highly sedentary). Thirty-five percent of the stroke survivors allocated to another movement behavior pattern within the first two years, of whom 63% deteriorated to a movement behavior pattern with higher health risks. After two years there were, 19% sedentary exercisers, 42% sedentary movers, and 39% sedentary prolongers.

CONCLUSIONS

The composition of movement behavior patterns remains stable over time. However, individuals change their movement behavior. Significantly more people allocated to a movement behavior pattern with higher health risks. The increase of people allocated to sedentary movers and sedentary prolongers is of great concern. It underlines the importance of improving or maintaining healthy movement behavior to prevent future health risks after stroke.

Exercise behavior patterns and associations with subjective well-being during the COVID-19 pandemic: A cross-sectional study in Brazil

Introduction

The COVID-19 pandemic has affected the behavior and practice of planned and structured physical exercises. This study aimed to investigate the association between changes in physical exercise behavior and subjective well-being during the COVID-19 pandemic in Brazil.

Methods

This cross-sectional study was performed in Brazil and included a total of 595 individuals recruited through social media platforms, personal and professional contacts. Each participant responded to self-completed questionnaire via an online survey between March 29 and May 7, 2020. The characteristics of physical exercise (frequency, intensity, and duration) were collected before and during the pandemic. The subjective state of mood was measured through the Profile of Mood States (POMS) questionnaire during the pandemic. A generalized linear model was employed for the analysis.

Results

Exercising during the pandemic only promoted protective effects on the subjective mood. An exercise frequency of 3-5 days/week was associated with improved vigor and between 6-7 days/week with improved vigor and total mood when compared to not exercising at all (p < .005). A moderate intensity was associated with improved vigor, and a high intensity with improved vigor, total mood, and less fatigue in comparison to low-intensity exercise programs (p < 0.05). Maintaining the same duration of exercise sessions during the pandemic was associated with lower scores of depression/anxiety, fatigue and irritability, and improved vigor and total mood, while performing longer sessions with improved vigor when compared to short exercise sessions (p < .005).

Conclusion

Regular exercising during the pandemic promotes positive changes in the subjective well-being. Our results reinforce the need for adopting and maintaining a physical exercise routine during the COVID-19 pandemic as a protective effect on mental health.

Movement syndromes of a Neotropical frugivorous bat inhabiting heterogeneous landscapes in Brazil

BACKGROUND

There is growing evidence that individuals within populations can vary in both habitat use and movement behavior, but it is still not clear how these two relate to each other. The aim of this study was to test if and how individual bats in a Stunira lilium population differ in their movement activity and preferences for landscape features in a correlated manner.

METHODS

We collected data on movements of 27 individuals using radio telemetry. We fitted a heterogeneous-space diffusion model to the movement data in order to evaluate signals of movement variation among individuals.

RESULTS

S. lilium individuals generally preferred open habitat with Solanum fruits, regularly switched between forest and open areas, and showed high site fidelity. Movement variation among individuals could be summarized in four movement syndromes: (1) average individuals, (2) forest specialists, (3) explorers which prefer Piper, and (4) open area specialists which prefer Solanum and Cecropia.

CONCLUSIONS

Individual preferences for landscape features plus food resource and movement activity were correlated, resulting in different movement syndromes. Individual variation in preferences for landscape elements and food resources highlight the importance of incorporating explicitly the interaction between landscape structure and individual heterogeneity in descriptions of animal movement.

Effect of Lead Exposure on Jumping Ability in Pelophylax nigromaculata

Jumping ability determines the likelihood of survival and reproduction of amphibians. To study the toxic effect of lead (Pb) on the jumping ability of amphibians, Pelophylax nigromaculata were treated with 0, 1 and 10 mg/L Pb for 10 days and 20 days each. The results showed that for both treatment time (10 days and 20 days), compared to the control group, the 1 mg/L Pb treatment had no significant effect on jumping parameters. Compared to the control group, the maximum jumping height, distance, speed and acceleration in the 10-day 10 mg/L Pb treatment group increased significantly, but after 20 days the jumping parameters decreased significantly. With an increase in duration and concentration, the correlation coefficient and the correlation between these jumping parameters decreased. Our results indicate that an exposure to 10 mg/L Pb for 20 days has a significant negative effect on the jumping ability of amphibians.

Establishment of a comprehensive analysis method for the microfaunal movement in activated sludge

Microfaunal identification and analysis are very complex; thus, an image analysis method was utilized in this paper to overcome the shortcomings of using the number, dominant species, and diversity of population structure of microfauna as activated sludge indicators. Based on a classification of microfaunal movement, the quantitative processing and analysis of the micro-video frame image of microfaunal movement were carried out by using the Image J software. Background subtraction method was utilized to detect target microfauna by matching target area features to track microfaunal movement. Three parameters, namely, motion trajectory (L), consecutive frame of motion paths (S_i), and average change rate of extent [Formula: see text], were selected to represent the motion trajectory and mass center of microfauna. Four motion-velocity parameters, namely, the left and right rotation angles of adjacent frames (∆α_i), instantaneous velocity (V_i), average linear velocity ([Formula: see text]), and average angular velocity ([Formula: see text]), were selected to characterize the movement modes of microfauna. Finally, a motion analysis method based on the Image J software was established to demonstrate the different motion modes of microfauna in activated sludge. This study provides a methodological foundation for the establishment of a new method of microfauna as indicator. Based on this method, the correlation between the microfaunal motion velocity and activated sludge flocs was analyzed.

Effects of habitat modifications on the movement behavior of animals: the case study of Fish Aggregating Devices (FADs) and tropical tunas

BACKGROUND

Aggregation sites represent important sources of environmental heterogeneity and can modify the movement behavior of animals. When these sites are artificially established through anthropogenic actions, the consequent alterations to animal movements may impact their ecology with potential implications for their fitness. Floating objects represent important sources of habitat heterogeneity for tropical tunas, beneath which these species naturally aggregate in large numbers. Man-made floating objects, called Fish Aggregating Devices (FAD), are used by fishers on a massive scale to facilitate fishing operations. In addition to the direct impacts that fishing with FADs has on tuna populations, assessing the effects of increasing the numbers of FADs on the ecology of tuna is key for generating sound management and conservation measures.

METHODS

This study investigates the effects of increasing numbers of FADs (aggregation sites) on the movements of tunas, through the comparison of electronic tagging data recorded from 146 individuals tunas (yellowfin tuna, Thunnus albacares, and skipjack tuna, Katsuwonus pelamis) tagged in three instrumented anchored FAD arrays (Mauritius, Oahu-Hawaii and Maldives), that differed according to their distances among neighboring FADs. The effect of increasing inter-FAD distances is studied considering a set of indices (residence times at FADs and absence (travel) times between two visits at FADs) and their trends.

RESULTS

When inter-FAD distances decrease, tuna visit more FADs (higher connectivity between FADs), spend less time travelling between FADs and more time associated with them. The trends observed for the absence (travel) times appear to be compatible with a random-search component in the movement behaviour of tunas. Conversely, FAD residence times showed opposite trends, which could be a result of social behavior and/or prey availability.

CONCLUSION

Our results provide the first evidence of changes in tuna associative behavior for increasing FAD densities. More generally, they highlight the need for comparing animal movements in heterogeneous habitats in order to improve understanding of the impacts of anthropogenic habitat modifications on the ecology of wild animals.

Initial impact of the COVID-19 pandemic on physical activity and sedentary behavior in hypertensive older adults: An accelerometer-based analysis

Background

This study reports the accelerometer-based physical activity (PA) and sedentary behavior (SB) before and during the COVID-19 pandemic in hypertensive older adults.

Methods

Thirty-five hypertensive older adults were included in this observational study. Accelerometer-based PA and SB measures were assessed before (January to March 2020) and during (June 2020) the COVID-19 pandemic. Linear mixed models were used to assess within-group changes in PA and SB measures, adjusted by accelerometer wear time.

Results

Before COVID-19 pandemic participants presented: 5809 steps/day (SE = 366), 303.1 min/day (SE = 11.9) of light PA, 15.5 min/day (SE = 2.2) of moderate-vigorous PA, and 653.0 min/day (SE = 12.6) of SB. During COVID-19 pandemic there was a decrease in steps/day (β = −886 steps/day, SE = 361, p = 0.018), in moderate-vigorous PA (β = −2.8 min/day, SE = 2.4, p = 0.018), and a trend in light PA (β = −26.6 min/day, SE = 13.4, p = 0.053). In addition, SB increased during the COVID-19 pandemic (β = 29.6 min/day, SE = 13.4, p = 0.032). The magnitude of changes was greater on the weekend, mainly for steps/day (β = −1739 steps/day, SE = 424, p < 0.001) and the SB pattern (more time spent in bouts of ≥10 and 30 min, less breaks/day and breaks/h).

Conclusions

The COVID-19 pandemic may elicit unhealthy changes in movement behavior in hypertensive older adults. Lower PA, higher and more prolonged SB on the weekend are the main features of the behavioral changes.

•

Unhealthy changes in movement behavior were observed during the COVID-19 pandemic.

•

Hypertensive older adults decreased steps/day and time spent in physical activities.

•

An increase in time spent in sedentary behavior (SB) was observed.

•

The time spent in prolonged SB increased and the breaks in SB decreased.

•

Greater unhealthy changes in movement behavior occurred on weekend.

Growth parameter k and location affect body size responses to spatial protection by exploited rockfishes

For many fish taxa, trophic position and relative fecundity increase with body size, yet fisheries remove the largest individuals, altering food webs and reducing population productivity. Marine reserves and other forms of spatial protection can help mitigate this problem, but the effectiveness of these management tools may vary interspecifically and spatially. Using visual survey data collected on the Central Coast of British Columbia, for 12 species of exploited rockfish we found that body size responses to spatial fishery closures depended on interspecific variation in growth parameter k (the rate at which the asymptotic body size is approached) and on location. For two closures, relative body sizes were larger at protected than at adjacent fished sites, and these differences were greater for species with lower k values. Reduced fishery mortality likely drove these results, as an unfished species did not respond to spatial protection. For three closures, however, body sizes did not differ between protected and adjacent fished sites, and for another closure species with higher k values were larger at fished than at protected sites while species with lower k values had similar sizes in both treatments. Variation in the age of closures is unlikely to have influenced results, as most data were collected when closures were 13 to 15-years-old. Rather, the lack of larger fish inside four of six spatial fishery closures potentially reflects a combination of smaller size of the area protected, poor fisher compliance, and lower oceanographic productivity. Interspecific differences in movement behavior did not affect body size responses to spatial protection. To improve understanding, additional research should be conducted at deeper depths encompassing the distribution of older, larger fish. Our study—which was conceptualized and executed by an alliance of Indigenous peoples seeking to restore rockfishes—illustrates how life history and behavioral theory provide a useful lens for framing and interpreting species differences in responses to spatial protection.

Towards the restoration of the Mesoamerican Biological Corridor for large mammals in Panama: comparing multi-species occupancy to movement models

BACKGROUND

Habitat fragmentation is a primary driver of wildlife loss, and the establishment of biological corridors is a conservation strategy to mitigate this problem. Identifying areas with high potential functional connectivity typically relies on the assessment of landscape resistance to movement. Many modeling approaches exist to estimate resistance surfaces but to date only a handful of studies compared the outputs resulting from different methods. Moreover, as many species are threatened by fragmentation, effective biodiversity conservation requires that corridors simultaneously meet the needs of multiple species. While many corridor planning initiatives focus on single species, we here used a combination of data types and analytical approaches to identify and compare corridors for several large mammal species within the Panama portion of the Mesoamerican Biological Corridor.

METHODS

We divided a large mammal assemblage into two groups depending on the species sensitivity to habitat disturbance. We subsequently used cost-distance methods to produce multi-species corridors which were modeled on the basis of (i) occupancy of nine species derived from camera trapping data collected across Panama, and (ii) step selection functions based on GPS telemetry data from white-lipped peccary Tayassu pecari, puma Puma concolor, and ocelot Leopardus pardalis. In addition to different data sources and species groups, we also used different transformation curves to convert occupancy and step-selection results into landscape resistance values.

RESULTS

Corridors modeled differed between sensitive and tolerant species, between the data sets, and between the transformation curves. There were more corridors identified for tolerant species than for sensitive species. For tolerant species, several corridors developed with occupancy data overlapped with corridors produced with step selection functions, but this was not the case for sensitive species.

CONCLUSION

Our study represents the first comparison of multispecies corridors parametrized with step selection functions versus occupancy models. Given the wide variability in output corridors, our findings underscore the need to consider the ecological requirements of several species. Our results also suggest that occupancy models can be used for estimating connectivity of generalist species. Finally, this effort allowed to identify important corridors within the MBC (i) at a country scale and (ii) for several species simultaneously to accurately inform the local authorities in conservation planning. The approach we present is reproducible in other sites and/or for other species.

Flexible resource use strategies of a central-place forager experiencing dynamic risk and opportunity

BACKGROUND

Movement decisions made in space and time define how wildlife meet competing extrinsic and intrinsic demands to maximize fitness. Differential selection of resource patches provides one example of how to measure how animals balance conflicting demands. We hypothesized that individual spatial selection of patch types between dynamic seasons would signify flexible strategies used to minimize risk and optimize foraging efforts.

METHODS

We used data collected from GPS loggers on golden-mantled ground squirrels (Callospermophilus lateralis) to model selection or avoidance of resources in two seasons of seed availability and one season in which no seeds were available. Movement decisions were measured in short-term discrete time intervals using high resolution location data. Selection or avoidance of specific resource features that entail fitness consequences were then assessed using resource selection functions.

RESULTS

Seasonality of food availability, food type, and spatial distribution of food largely influenced how individuals selected resources within their home ranges. Overall, when seeds were available, individuals mediated risks of predation and loss of food by using patches closer to refuge and selected intermediate distances to the burrow. When food was not available, individuals minimized exposure to heightened risk by staying close to the burrow and avoiding riskier patch types.

CONCLUSIONS

Results indicate that individuals used flexible, dynamic strategies to select habitat patches which may allow them to balance conflicting seasonal demands. Advances in GPS technology for research of small mammals provide greater insight into how prey species in high risk environments differentially use resources to minimize risk and maintain fitness.

Visuo-tactile congruency influences the body schema during full body ownership illusion

•

Visuo-tactile congruency influences the body schema, but not the body image.

•

Movement behavior may provide a window into the unconscious body schema.

•

We present novel methods to distort avatars and Euclidean space in virtual reality.

Previous research showed that full body ownership illusions in virtual reality (VR) can be robustly induced by providing congruent visual stimulation, and that congruent tactile experiences provide a dispensable extension to an already established phenomenon. Here we show that visuo-tactile congruency indeed does not add to already high measures for body ownership on explicit measures, but does modulate movement behavior when walking in the laboratory. Specifically, participants who took ownership over a more corpulent virtual body with intact visuo-tactile congruency increased safety distances towards the laboratory’s walls compared to participants who experienced the same illusion with deteriorated visuo-tactile congruency. This effect is in line with the body schema more readily adapting to a more corpulent body after receiving congruent tactile information. We conclude that the action-oriented, unconscious body schema relies more heavily on tactile information compared to more explicit aspects of body ownership.

Ecological correlates of blue whale movement behavior and its predictability in the California Current Ecosystem during the summer-fall feeding season

BACKGROUND

Species distribution models have shown that blue whales (Balaenoptera musculus) occur seasonally in high densities in the most biologically productive regions of the California Current Ecosystem (CCE). Satellite telemetry studies have additionally shown that blue whales in the CCE regularly switch between behavioral states consistent with area-restricted searching (ARS) and transiting, indicative of foraging in and moving among prey patches, respectively. However, the relationship between the environmental correlates that serve as a proxy of prey relative to blue whale movement behavior has not been quantitatively assessed.

METHODS

We investigated the association between blue whale behavioral state and environmental predictors in the coastal environments of the CCE using a long-term satellite tracking data set (72 tagged whales; summer-fall months 1998-2008), and predicted the likelihood of ARS behavior at tracked locations using nonparametric multiplicative regression models. The models were built using data from years of cool, productive conditions and validated against years of warm, low-productivity conditions.

RESULTS

The best model contained four predictors: chlorophyll-a, sea surface temperature, and seafloor aspect and depth. This model estimated highest ARS likelihood (> 0.8) in areas with high chlorophyll-a levels (> 0.65 mg/m³), intermediate sea surface temperatures (11.6-17.5 °C), and shallow depths (< 850 m). Overall, the model correctly predicted behavioral state throughout the coastal environments of the CCE, while the validation indicated an ecosystem-wide reduction in ARS likelihood during warm years, especially in the southern portion. For comparison, a spatial coordinates model (longitude × latitude) performed slightly better than the environmental model during warm years, providing further evidence that blue whales exhibit strong foraging site fidelity, even when conditions are not conducive to successful foraging.

CONCLUSIONS

We showed that blue whale behavioral state in the CCE was predictable from environmental correlates and that ARS behavior was most prevalent in regions of known high whale density, likely reflecting where large prey aggregations consistently develop in summer-fall. Our models of whale movement behavior enhanced our understanding of species distribution by further indicating where foraging was more likely, which could be of value in the identification of key regions of importance for endangered species in management considerations. The models also provided evidence that decadal-scale environmental fluctuations can drive shifts in the distribution and foraging success of this blue whale population.

Hourly movement decisions indicate how a large carnivore inhabits developed landscapes

The ecology of wildlife living in proximity to humans often differs from that in more natural places. Animals may perceive anthropogenic features and people as threats, exhibiting avoidance behavior, or may acclimate to human activities. As development expands globally, changes in the ecology of species in response to human phenomena may determine whether animals persist in these changing environments. We hypothesize that American black bears (Ursus americanus) persist within developed areas by effectively avoiding risky landscape features. We test this by quantifying changes in the movements of adult females from a population living within exurban and suburban development. We collected hourly GPS data from 23 individuals from 2012 to 2014 and used step-selection functions to estimate selection for anthropogenic features. Females were more avoidant of roads and highways when with cubs than without and were more responsive to increased traffic volume. As bears occupied greater housing densities, selection for housing increased, while avoidance of roads and responsiveness to traffic increased. Behavioral flexibility allowed bears in highly developed areas to alter selection and avoidance for anthropogenic features seasonally. These findings support the hypothesis that black bears perceive human activity as risky, and effectively avoid these risks while inhabiting developed areas. We document a high amount of individual variation in selection of anthropogenic features within the study population. Our findings suggest that initially, wildlife can successfully inhabit developed landscapes by effectively avoiding human activity. However, variation among individuals provides the capacity for population-level shifts in behavior over time.

Can fractal methods applied to video tracking detect the effects of deltamethrin pesticide or mercury on the locomotion behavior of shrimps?

Shrimps can accumulate environmental toxicants and suffer behavioral changes. However, methods to quantitatively detect changes in the behavior of these shrimps are still needed. The present study aims to verify whether mathematical and fractal methods applied to video tracking can adequately describe changes in the locomotion behavior of shrimps exposed to low concentrations of toxic chemicals, such as 0.15µgL^-1 deltamethrin pesticide or 10µgL^-1 mercuric chloride. Results showed no change after 1min, 4, 24, and 48h of treatment. However, after 72 and 96h of treatment, both the linear methods describing the track length, mean speed, mean distance from the current to the previous track point, as well as the non-linear methods of fractal dimension (box counting or information entropy) and multifractal analysis were able to detect changes in the locomotion behavior of shrimps exposed to deltamethrin. Analysis of angular parameters of the track points vectors and lacunarity were not sensitive to those changes. None of the methods showed adverse effects to mercury exposure. These mathematical and fractal methods applicable to software represent low cost useful tools in the toxicological analyses of shrimps for quality of food, water and biomonitoring of ecosystems.

Ungulates rely less on visual cues, but more on adapting movement behaviour, when searching for forage

Finding suitable forage patches in a heterogeneous landscape, where patches change dynamically both spatially and temporally could be challenging to large herbivores, especially if they have no a priori knowledge of the location of the patches. We tested whether three large grazing herbivores with a variety of different traits improve their efficiency when foraging at a heterogeneous habitat patch scale by using visual cues to gain a priori knowledge about potential higher value foraging patches. For each species (zebra (Equus burchelli), red hartebeest (Alcelaphus buselaphus subspecies camaa) and eland (Tragelaphus oryx)), we used step lengths and directionality of movement to infer whether they were using visual cues to find suitable forage patches at a habitat patch scale. Step lengths were significantly longer for all species when moving to non-visible patches than to visible patches, but all movements showed little directionality. Of the three species, zebra movements were the most directional. Red hartebeest had the shortest step lengths and zebra the longest. We conclude that these large grazing herbivores may not exclusively use visual cues when foraging at a habitat patch scale, but would rather adapt their movement behaviour, mainly step length, to the heterogeneity of the specific landscape.

The Fokker-Planck law of diffusion and pattern formation in heterogeneous environments

We analyze the influence of spatially inhomogeneous diffusion on several common ecological problems. Diffusion is modeled with Fick's law and the Fokker-Planck law of diffusion. We discuss the differences between the two formalisms and when to use either the one or the other. In doing so, we start with a pure diffusion equation, then turn to a reaction-diffusion system with one logistically growing component which invades the spatial domain. We also look at systems of two reacting components, namely a trimolecular oscillating chemical model system and an excitable predator-prey model. Contrary to Fickian diffusion, spatial inhomogeneities promote spatial and spatiotemporal pattern formation in case of Fokker-Planck diffusion.

How animals move along? Exactly solvable model of superdiffusive spread resulting from animal's decision making

Patterns of individual animal movement have been a focus of considerable attention recently. Of particular interest is a question how different macroscopic properties of animal dispersal result from the stochastic processes occurring on the microscale of the individual behavior. In this paper, we perform a comprehensive analytical study of a model where the animal changes the movement velocity as a result of its behavioral response to environmental stochasticity. The stochasticity is assumed to manifest itself through certain signals, and the animal modifies its velocity as a response to the signals. We consider two different cases, i.e. where the change in the velocity is or is not correlated to its current value. We show that in both cases the early, transient stage of the animal movement is super-diffusive, i.e. ballistic. The large-time asymptotic behavior appears to be diffusive in the uncorrelated case but super-ballistic in the correlated case. We also calculate analytically the dispersal kernel of the movement and show that, whilst it converge to a normal distribution in the large-time limit, it possesses a fatter tail during the transient stage, i.e. at early and intermediate time. Since the transients are known to be highly relevant in ecology, our findings may indicate that the fat tails and superdiffusive spread that are sometimes observed in the movement data may be a feature of the transitional dynamics rather than an inherent property of the animal movement.

Biological early warning system based on the responses of aquatic organisms to disturbances: a review

Aquatic ecosystems are subject to a number of anthropogenic disturbances, including environmental toxicants. The efficient monitoring of water resources is fundamental for effective management of water quality and aquatic ecosystems. Spot sampling and continuous water quality monitoring based on physicochemical factors are conducted to assess water quality. However, not all contaminants or synergistic and antagonistic toxic effects can be determined by solely analyzing the physicochemical factors. Thus, various biotests have been developed using long-term and automatic observation studies based on the ability of the aquatic organisms to continuously sense a wide range of pollutants. In addition, a biological early warning system (BEWS) has been developed based on the response behaviors of organisms to continuously detect a wide range of pollutants for effective water quality monitoring and management. However, large amounts of data exhibiting non-linearity and individual behavioral variation are continuously accumulated over long-term and continuous behavioral monitoring studies. Thus, appropriate mathematical and computational data analyses are necessary to manage and interpret such large datasets. Here, we review the development and application of BEWS by using various groups of organisms and the computational methods used to process the behavioral monitoring data.