Earthquake networks based on similar activity patterns

The transition to independent foraging represents an important developmental stage in the life cycle of most vertebrate animals. Juveniles differ from adults in various life history traits and tend to survive less well than adults in most long-lived animals. Several hypotheses have been proposed to explain higher mortality including that of inadequate/inferior foraging skills compared to adults, young naive individuals combining lack of experience and physical immaturity. Thus a change in behaviour, resulting in an improvement of skills acquired from growing experience, is expected to occur during a period of learning through the immaturity phase. Very few studies have investigated the ontogeny of foraging behaviour over long periods of time, particularly in long-lived pelagic seabirds, due to the difficulty of obtaining individual tracking data over several years. We investigated the foraging behaviour, through activity patterns, during the successive life stages of the endangered Amsterdam albatross by using miniaturized activity loggers on naive juveniles, immatures and adults. Juvenile naive birds during their first month at sea after leaving their colony exhibited lower foraging effort (greater proportion of time spent sitting on water, higher duration and more numerous bouts on water, and lower duration and less numerous flying bouts). Juveniles reached similar activity values to those of immatures and adults as early as the 2nd-3rd months since independence, suggesting a progressive improvement of foraging performances during the first two months since fledging. We found support for the body-size hypothesis with respect to sex differences in activity parameters according to time elapsed since departure from the colony and month of the year, consistent with the important sexual dimorphism in the Amsterdam albatross. Whatever the life stage considered, activity parameters exhibited temporal variability reflecting the modulation of foraging behaviour possibly linked to both extrinsic (i.e. environmental conditions such as variability in food resources or in wind) and intrinsic (i.e. energetic demands linked to plumage renew during moult) factors.

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Perturbation-specific responses by two neural circuits generating similar activity patterns

Current Biology ◽

10.1016/j.cub.2021.08.042 ◽

2021 ◽

Author(s):

Daniel J. Powell ◽

Eve Marder ◽

Michael P. Nusbaum

Keyword(s):

Neural Circuits ◽

Activity Patterns ◽

Similar Activity

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Activity patterns of medium and large mammals in two savanna ecosystems in the Colombian Llanos

Revista de la Academia Colombiana de Ciencias Exactas Físicas y Naturales ◽

10.18257/raccefyn.1461 ◽

2021 ◽

Author(s):

Dennis Castillo-Figueroa ◽

Daniela Martínez-Medina ◽

Miguel E. Rodríguez-Posada

Keyword(s):

Mammalian Species ◽

Activity Patterns ◽

Camera Traps ◽

Large Mammals ◽

Continuous Processes ◽

Similar Activity ◽

Terrestrial Mammals ◽

Neotropical Savannas ◽

History Of ◽

Oil Gas

Neotropical savannas have undergone continuous processes of landscape transformation (e.g., agriculture, oil, gas, and hydrocarbon industry) and very little is known about the ecology and natural history of key biological groups such as terrestrial mammals while the information on behavioral aspects of mammalian species in these ecosystems is very scarce. Here, we aimed to describe the activity patterns of medium and large mammals in two savanna ecosystems in the Colombian Llanos. A set of 60 camera traps was installed in the two ecosystems for 35 days (2100 camera days). We described the activity patterns of nine predominantly nocturnal species. We found no difference in circadian distributions of mammals between ecosystems. Cuniculus paca Linnaeus 1758 and Dasyprocta fuliginosa Wagler 1832 showed patterns of exclusion probably due to competition whereas other species like Tamandua tetradactyla Linnaeus1758 and Myrmecophaga tridactyla Linnaeus 1758 displayed similar activity patterns. We highlight the importance of savannas for the conservation of these species and discuss the relevance of studies on activity patterns for mammal ecology and conservation in Neotropical savannas.

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The Virus is Coming! The Ways the Canadian-Born and Foreign-Born Changed Weekly Activities During the Pandemic

10.31235/osf.io/a2btf ◽

2021 ◽

Author(s):

Fernando Mata

Keyword(s):

Substance Use ◽

Activity Patterns ◽

Main Tool ◽

Principal Component ◽

Food Choices ◽

Statistical Testing ◽

Foreign Born ◽

Similar Activity ◽

Canadian Perspective ◽

Mean Differences

During epidemics, individuals change their weekly activities to increase their sense of personal security, health, efficacy and comfort. This study looks at changes in weekly activities reported by Canadians and foreign-born citizens during the first wave of the COVID-19 pandemic in Canada. The data for the study is drawn from a combined survey of two cycles of the CPSS (Canadian Perspective Series) surveys 2 and 4 which were conducted between May 4 and July 26, 2020. The combined survey consisted of 8,818 adult respondents (7,280 Canadian-born and 1,538 Foreign-born respondents). Weekly activities were measured by 25 survey questions which collected information on habits such as washing hands, avoiding crowds, watching more T.V., internet use and exercising. Principal Component Analysis (PCA) was used as the main tool for the statistical analysis of the data. Statistical testing of mean differences revealed that Canadian and foreign-born groups differed from each other in 15 out of the 25 activity items tested. PCA identified six major domains of weekly activities. Immigrants displayed similar activity patterns compared to the Canadian-born concerning the Sanitary, Leisure, Planning and Hoarding domain of activities but were found somewhat dissimilar in terms of the Sheltering and Substance use activity domains. During the pandemic lockdown, immigrants "hunkered down" and were more proactive in adopting sheltering types of activities such as cancelling travel plans, exercising more indoors than outdoors, practicing meditation and making better food choices. In doing so, they also avoided substance use as pandemic coping activities such as higher consumption of alcohol, tobacco and cannabis compared to the Canadian-born.

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Daily activity and microhabitat use of sympatric lizards from Serra do Cipó, southeastern Brazil

Iheringia Série Zoologia ◽

10.1590/s0073-47212010000400008 ◽

2010 ◽

Vol 100 (4) ◽

pp. 336-340 ◽

Cited By ~ 8

Author(s):

Renato Filogonio ◽

Fernanda S. Del Lama ◽

Leonardo L. Machado ◽

Michelle Drumond ◽

Isabella Zanon ◽

...

Keyword(s):

Daily Activity ◽

Activity Patterns ◽

Southeastern Brazil ◽

Microhabitat Use ◽

Low Density ◽

Campos Rupestres ◽

Lizard Species ◽

Similar Activity ◽

Serra Do Cipó ◽

Environmental Temperatures

We studied the influence of seasonality on the daily activity pattern and microhabitat use of three sympatric lizard species, Cnemidophorus ocellifer Spix, 1825 (Teiidae), Tropidurus montanus Rodrigues, 1987 and Eurolophosaurus nanuzae (Rodrigues, 1981) (Tropiduridae), in an area of campos rupestres (rocky fields) habitat in state of Minas Gerais, Brazil. Cnemidophorus ocellifer exhibited low density and activity concentrated within the hottest hours of the day, and was observed mainly on shaded rocks. Tropidurus montanus and E. nanuzae had similar activity patterns that did not vary between seasons. Activity of T. montanus was related to environmental temperatures. However, we did not find such relationships for E. nanuzae during the dry season. Both T. montanus and E. nanuzae were sighted mainly on exposed rocks. Extension of activity varied between seasons, shorter for C. ocellifer and longer for T. montanus and E. nanuzae during the rainy season.

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Disparate energy consumption despite similar network activity

10.1101/2021.07.30.454484 ◽

2021 ◽

Author(s):

Michael Deistler ◽

Jakob H Macke ◽

Pedro J Goncalves

Keyword(s):

Energy Consumption ◽

Neural Circuits ◽

Specific Activity ◽

Activity Patterns ◽

Network Models ◽

Metabolic Cost ◽

Network Activity ◽

Metabolic Efficiency ◽

Cancer Borealis ◽

Similar Activity

Neural circuits can produce similar activity patterns from vastly different combinations of channel and synaptic conductances. These conductances are tuned for specific activity patterns but might also reflect additional constraints, such as metabolic cost or robustness to perturbations. How do such constraints influence the range of permissible conductances? Here, we investigate how metabolic cost affects the parameters of neural circuits with similar activity in a model of the pyloric network of the crab Cancer borealis. We use a novel machine learning method to identify a range of network models that can generate activity patterns matching experimental data. We find that neural circuits can consume largely different amounts of energy despite similar circuit activity. We then study how circuit parameters get constrained by minimizing energy consumption and identify circuit parameters that might be subject to metabolic tuning. Finally, we investigate the interaction between metabolic cost and temperature robustness. We show that metabolic cost can vary across temperatures, but that robustness to temperature changes does not necessarily incur an increased metabolic cost. Our analyses show that, despite metabolic efficiency and temperature robustness constraining circuit parameters, neural systems can generate functional, efficient, and robust network activity with widely disparate sets of conductances.

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Predicting spatial activity patterns in a neural map from a probabilistic atlas of 3-D reconstructed neurons

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140439 ◽

1995 ◽

Vol 53 ◽

pp. 812-813

Author(s):

G. Jacobs ◽

F. Theunissen

Keyword(s):

Activity Patterns ◽

Three Dimensional ◽

Sensory System ◽

Neural System ◽

Probabilistic Atlas ◽

Uniform Sample ◽

Dimensional Reconstruction ◽

The Time Domain ◽

And Function ◽

Visualization Techniques

In order to understand how the algorithms underlying neural computation are implemented within any neural system, it is necessary to understand details of the anatomy, physiology and global organization of the neurons from which the system is constructed. Information is represented in neural systems by patterns of activity that vary in both their spatial extent and in the time domain. One of the great challenges to microscopists is to devise methods for imaging these patterns of activity and to correlate them with the underlying neuroanatomy and physiology. We have addressed this problem by using a combination of three dimensional reconstruction techniques, quantitative analysis and computer visualization techniques to build a probabilistic atlas of a neural map in an insect sensory system. The principal goal of this study was to derive a quantitative representation of the map, based on a uniform sample of afferents that was of sufficient size to allow statistically meaningful analyses of the relationships between structure and function.

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Inducing Unconscious Stress

Journal of Psychophysiology ◽

10.1027/0269-8803/a000247 ◽

2020 ◽

Vol 34 (3) ◽

pp. 192-201

Author(s):

Melanie M. van der Ploeg ◽

Jos F. Brosschot ◽

Markus Quirin ◽

Richard D. Lane ◽

Bart Verkuil

Keyword(s):

Repeated Measures ◽

Activity Patterns ◽

Physiological Changes ◽

Implicit Measures ◽

Prime Word ◽

Student Sample ◽

Priming Task ◽

Subject Design ◽

The Relationship ◽

Stress And Health

Abstract. Stress-related stimuli may be presented outside of awareness and may ultimately influence health by causing repetitive increases in physiological parameters, such as blood pressure (BP). In this study, we aimed to corroborate previous studies that demonstrated BP effects of subliminally presented stress-related stimuli. This would add evidence to the hypothesis that unconscious manifestations of stress can affect somatic health. Additionally, we suggest that these findings may be extended by measuring affective changes relating to these physiological changes, using measures for self-reported and implicit positive and negative affectivity. Using a repeated measures between-subject design, we presented either the prime word “angry” ( n = 26) or “relax” ( n = 28) subliminally (17 ms) for 100 trials to a student sample and measured systolic and diastolic BP, heart rate (HR), and affect. The “angry” prime, compared to the “relax” prime, did not affect any of the outcome variables. During the priming task, a higher level of implicit negative affect (INA) was associated with a lower systolic BP and diastolic BP. No association was found with HR. Self-reported affect and implicit positive affect were not related to the cardiovascular (CV) activity. In sum, anger and relax primes elicited similar CV activity patterns, but implicit measures of affect may provide a new method to examine the relationship between (unconscious) stress and health.

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