Bacteria and game theory: the rise and fall of cooperation in spatially heterogeneous environments.

PubMed

Lambert, Guillaume; Vyawahare, Saurabh; Austin, Robert H

2014-08-06

One of the predictions of game theory is that cooperative behaviours are vulnerable to exploitation by selfish individuals, but this result seemingly contradicts the survival of cooperation observed in nature. In this review, we will introduce game theoretical concepts that lead to this conclusion and show how the spatial competition dynamics between microorganisms can be used to model the survival and maintenance of cooperation. In particular, we focus on how Escherichia coli bacteria with a growth advantage in stationary phase (GASP) phenotype maintain a proliferative phenotype when faced with overcrowding to gain a fitness advantage over wild-type populations. We review recent experimental approaches studying the growth dynamics of competing GASP and wild-type strains of E. coli inside interconnected microfabricated habitats and use a game theoretical approach to analyse the observed inter-species interactions. We describe how the use of evolutionary game theory and the ideal free distribution accurately models the spatial distribution of cooperative and selfish individuals in spatially heterogeneous environments. Using bacteria as a model system of cooperative and selfish behaviours may lead to a better understanding of the competition dynamics of other organisms-including tumour-host interactions during cancer development and metastasis.

Living in the branches: population dynamics and ecological processes in dendritic networks

USGS Publications Warehouse

Grant, E.H.C.; Lowe, W.H.; Fagan, W.F.

2007-01-01

Spatial structure regulates and modifies processes at several levels of ecological organization (e.g. individual/genetic, population and community) and is thus a key component of complex systems, where knowledge at a small scale can be insufficient for understanding system behaviour at a larger scale. Recent syntheses outline potential applications of network theory to ecological systems, but do not address the implications of physical structure for network dynamics. There is a specific need to examine how dendritic habitat structure, such as that found in stream, hedgerow and cave networks, influences ecological processes. Although dendritic networks are one type of ecological network, they are distinguished by two fundamental characteristics: (1) both the branches and the nodes serve as habitat, and (2) the specific spatial arrangement and hierarchical organization of these elements interacts with a species' movement behaviour to alter patterns of population distribution and abundance, and community interactions. Here, we summarize existing theory relating to ecological dynamics in dendritic networks, review empirical studies examining the population- and community-level consequences of these networks, and suggest future research integrating spatial pattern and processes in dendritic systems.

Indirect effects of ecosystem engineering combine with consumer behaviour to determine the spatial distribution of herbivory.

PubMed

Griffen, Blaine D; Riley, Megan E; Cannizzo, Zachary J; Feller, Ilka C

2017-10-01

Ecosystem engineers alter environments by creating, modifying or destroying habitats. The indirect impacts of ecosystem engineering on trophic interactions should depend on the combination of the spatial distribution of engineered structures and the foraging behaviour of consumers that use these structures as refuges. In this study, we assessed the indirect effects of ecosystem engineering by a wood-boring beetle in a neotropical mangrove forest system. We identified herbivory patterns in a dwarf mangrove forest on the archipelago of Twin Cays, Belize. Past wood-boring activity impacted more than one-third of trees through the creation of tree holes that are now used, presumably as predation or thermal refuge, by the herbivorous mangrove tree crab Aratus pisonii. The presence of these refuges had a significant impact on plant-animal interactions; herbivory was more than fivefold higher on trees influenced by tree holes relative to those that were completely isolated from these refuges. Additionally, herbivory decreased exponentially with increasing distance from tree holes. We use individual-based simulation modelling to demonstrate that the creation of these herbivory patterns depends on a combination of the use of engineered tree holes for refuge by tree crabs, and the use of two behaviour patterns in this species-site fidelity to a "home tree," and more frequent foraging near their home tree. We demonstrate that understanding the spatial distribution of herbivory in this system depends on combining both the use of ecosystem engineering structures with individual behavioural patterns of herbivores. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

The dual impact of ecology and management on social incentives in marine common-pool resource systems.

PubMed

Klein, E S; Barbier, M R; Watson, J R

2017-08-01

Understanding how and when cooperative human behaviour forms in common-pool resource systems is critical to illuminating social-ecological systems and designing governance institutions that promote sustainable resource use. Before assessing the full complexity of social dynamics, it is essential to understand, concretely and mechanistically, how resource dynamics and human actions interact to create incentives and pay-offs for social behaviours. Here, we investigated how such incentives for information sharing are affected by spatial dynamics and management in a common-pool resource system. Using interviews with fishermen to inform an agent-based model, we reveal generic mechanisms through which, for a given ecological setting characterized by the spatial dynamics of the resource, the two 'human factors' of information sharing and management may heterogeneously impact various members of a group for whom theory would otherwise predict the same strategy. When users can deplete the resource, these interactions are further affected by the management approach. Finally, we discuss the implications of alternative motivations, such as equity among fishermen and consistency of the fleet's output. Our results indicate that resource spatial dynamics, form of management and level of depletion can interact to alter the sociality of people in common-pool resource systems, providing necessary insight for future study of strategic decision processes.

Time-dependent spectral analysis of interactions within groups of walking pedestrians and vertical structural motion using wavelets

NASA Astrophysics Data System (ADS)

Bocian, M.; Brownjohn, J. M. W.; Racic, V.; Hester, D.; Quattrone, A.; Gilbert, L.; Beasley, R.

2018-05-01

A multi-scale and multi-object interaction phenomena can arise when a group of walking pedestrians crosses a structure capable of exhibiting dynamic response. This is because each pedestrian is an autonomous dynamic system capable of displaying intricate behaviour affected by social, psychological, biomechanical and environmental factors, including adaptations to the structural motion. Despite a wealth of mathematical models attempting to describe and simulate coupled crowd-structure system, their applicability can generally be considered uncertain. This can be assigned to a number of assumptions made in their development and the scarcity or unavailability of data suitable for their validation, in particular those associated with pedestrian-pedestrian and pedestrian-structure interaction. To alleviate this problem, data on behaviour of individual pedestrians within groups of six walkers with different spatial arrangements are gathered simultaneously with data on dynamic structural response of a footbridge, from a series of measurements utilising wireless motion monitors. Unlike in previous studies on coordination of pedestrian behaviour, the collected data can serve as a proxy for pedestrian vertical force, which is of critical importance from the point of view of structural stability. A bivariate analysis framework is proposed and applied to these data, encompassing wavelet transform, synchronisation measures based on Shannon entropy and circular statistics. A topological pedestrian map is contrived showing the strength and directionality of between-subjects interactions. It is found that the coordination in pedestrians' vertical force depends on the spatial collocation within a group, but it is generally weak. The relationship between the bridge and pedestrian behaviour is also analysed, revealing stronger propensity for pedestrians to coordinate their force with the structural motion rather than with each other.

Spatio-temporal interactions facilitate large carnivore sympatry across a resource gradient

PubMed Central

Karanth, K. Ullas; Srivathsa, Arjun; Puri, Mahi; Parameshwaran, Ravishankar; Kumar, N. Samba

2017-01-01

Species within a guild vary their use of time, space and resources, thereby enabling sympatry. As intra-guild competition intensifies, such behavioural adaptations may become prominent. We assessed mechanisms of facilitating sympatry among dhole (Cuon alpinus), leopard (Panthera pardus) and tiger (Panthera tigris) in tropical forests of India using camera-trap surveys. We examined population-level temporal, spatial and spatio-temporal segregation among them across four reserves representing a gradient of carnivore and prey densities. Temporal and spatial overlaps were higher at lower prey densities. Combined spatio-temporal overlap was minimal, possibly due to chance. We found fine-scale avoidance behaviours at one high-density reserve. Our results suggest that: (i) patterns of spatial, temporal and spatio-temporal segregation in sympatric carnivores do not necessarily mirror each other; (ii) carnivores are likely to adopt temporal, spatial, and spatio-temporal segregation as alternative mechanisms to facilitate sympatry; and (iii) carnivores show adaptability across a gradient of resource availability, a driver of inter-species competition. We discuss behavioural mechanisms that permit carnivores to co-occupy rather than dominate functional niches, and adaptations to varying intensities of competition that are likely to shape structure and dynamics of carnivore guilds. PMID:28179511

Spatio-temporal interactions facilitate large carnivore sympatry across a resource gradient.

PubMed

Karanth, K Ullas; Srivathsa, Arjun; Vasudev, Divya; Puri, Mahi; Parameshwaran, Ravishankar; Kumar, N Samba

2017-02-08

Species within a guild vary their use of time, space and resources, thereby enabling sympatry. As intra-guild competition intensifies, such behavioural adaptations may become prominent. We assessed mechanisms of facilitating sympatry among dhole ( Cuon alpinus ), leopard ( Panthera pardus ) and tiger ( Panthera tigris ) in tropical forests of India using camera-trap surveys. We examined population-level temporal, spatial and spatio-temporal segregation among them across four reserves representing a gradient of carnivore and prey densities. Temporal and spatial overlaps were higher at lower prey densities. Combined spatio-temporal overlap was minimal, possibly due to chance. We found fine-scale avoidance behaviours at one high-density reserve. Our results suggest that: (i) patterns of spatial, temporal and spatio-temporal segregation in sympatric carnivores do not necessarily mirror each other; (ii) carnivores are likely to adopt temporal, spatial, and spatio-temporal segregation as alternative mechanisms to facilitate sympatry; and (iii) carnivores show adaptability across a gradient of resource availability, a driver of inter-species competition. We discuss behavioural mechanisms that permit carnivores to co-occupy rather than dominate functional niches, and adaptations to varying intensities of competition that are likely to shape structure and dynamics of carnivore guilds. © 2017 The Author(s).

Social Behaviour of Captive Belugas, Delphinapterus Leucas.

NASA Astrophysics Data System (ADS)

Recchia, Cheri Anne

1994-01-01

Focal-animal sampling techniques developed for investigating social behaviour of terrestrial animals were adapted for studying captive belugas, providing quantitative descriptions of social relationships among individuals. Five groups of captive belugas were observed, allowing a cross -sectional view of sociality in groups of diverse sizes and compositions. Inter-individual distances were used to quantify patterns of spatial association. A set of social behaviours for which actor and recipient could be identified was defined to characterize dyadic interactions. The mother-calf pair spent more time together, and interacted more often than adults. The calf maintained proximity with his mother; larger adults generally maintained proximity with smaller adults. Among adults, larger groups performed more kinds of behaviours and interacted at higher rates than smaller groups. Within dyads, the larger whale performed more aggressive behaviours and the smaller whale more submissive behaviours. Clear dominance relations existed in three groups, with larger whales dominant to smaller whales. Vocalizations of three groups were classified subjectively, based on aural impressions and visual inspection of spectrograms, but most signals appeared graded. Statistical analyses of measured acoustic features confirmed subjective impressions that vocalizations could not be classified into discrete and homogeneous categories. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-553-5668; Fax 617-253-1690.).

The effect of individual variation on the structure and function of interaction networks in harvester ants

PubMed Central

Pinter-Wollman, Noa; Wollman, Roy; Guetz, Adam; Holmes, Susan; Gordon, Deborah M.

2011-01-01

Social insects exhibit coordinated behaviour without central control. Local interactions among individuals determine their behaviour and regulate the activity of the colony. Harvester ants are recruited for outside work, using networks of brief antennal contacts, in the nest chamber closest to the nest exit: the entrance chamber. Here, we combine empirical observations, image analysis and computer simulations to investigate the structure and function of the interaction network in the entrance chamber. Ant interactions were distributed heterogeneously in the chamber, with an interaction hot-spot at the entrance leading further into the nest. The distribution of the total interactions per ant followed a right-skewed distribution, indicating the presence of highly connected individuals. Numbers of ant encounters observed positively correlated with the duration of observation. Individuals varied in interaction frequency, even after accounting for the duration of observation. An ant's interaction frequency was explained by its path shape and location within the entrance chamber. Computer simulations demonstrate that variation among individuals in connectivity accelerates information flow to an extent equivalent to an increase in the total number of interactions. Individual variation in connectivity, arising from variation among ants in location and spatial behaviour, creates interaction centres, which may expedite information flow. PMID:21490001

The organisation of spatial and temporal relations in memory.

PubMed

Rondina, Renante; Curtiss, Kaitlin; Meltzer, Jed A; Barense, Morgan D; Ryan, Jennifer D

2017-04-01

Episodic memories are comprised of details of "where" and "when"; spatial and temporal relations, respectively. However, evidence from behavioural, neuropsychological, and neuroimaging studies has provided mixed interpretations about how memories for spatial and temporal relations are organised-they may be hierarchical, fully interactive, or independent. In the current study, we examined the interaction of memory for spatial and temporal relations. Using explicit reports and eye-tracking, we assessed younger and older adults' memory for spatial and temporal relations of objects that were presented singly across time in unique spatial locations. Explicit change detection of spatial relations was affected by a change in temporal relations, but explicit change detection of temporal relations was not affected by a change in spatial relations. Younger and older adults showed eye movement evidence of incidental memory for temporal relations, but only younger adults showed eye movement evidence of incidental memory for spatial relations. Together, these findings point towards a hierarchical organisation of relational memory. The implications of these findings are discussed in the context of the neural mechanisms that may support such a hierarchical organisation of memory.

Analysis of risk factors for T. brucei rhodesiense sleeping sickness within villages in south-east Uganda

PubMed Central

Zoller, Thomas; Fèvre, Eric M; Welburn, Susan C; Odiit, Martin; Coleman, Paul G

2008-01-01

Background Sleeping sickness (HAT) caused by T.b. rhodesiense is a major veterinary and human public health problem in Uganda. Previous studies have investigated spatial risk factors for T.b. rhodesiense at large geographic scales, but none have properly investigated such risk factors at small scales, i.e. within affected villages. In the present work, we use a case-control methodology to analyse both behavioural and spatial risk factors for HAT in an endemic area. Methods The present study investigates behavioural and occupational risk factors for infection with HAT within villages using a questionnaire-based case-control study conducted in 17 villages endemic for HAT in SE Uganda, and spatial risk factors in 4 high risk villages. For the spatial analysis, the location of homesteads with one or more cases of HAT up to three years prior to the beginning of the study was compared to all non-case homesteads. Analysing spatial associations with respect to irregularly shaped geographical objects required the development of a new approach to geographical analysis in combination with a logistic regression model. Results The study was able to identify, among other behavioural risk factors, having a family member with a history of HAT (p = 0.001) as well as proximity of a homestead to a nearby wetland area (p < 0.001) as strong risk factors for infection. The novel method of analysing complex spatial interactions used in the study can be applied to a range of other diseases. Conclusion Spatial risk factors for HAT are maintained across geographical scales; this consistency is useful in the design of decision support tools for intervention and prevention of the disease. Familial aggregation of cases was confirmed for T. b. rhodesiense HAT in the study and probably results from shared behavioural and spatial risk factors amongmembers of a household. PMID:18590541

An individual-orientated model of the emergence of despotic and egalitarian societies

PubMed Central

Hemelrijk, C. K.

1999-01-01

Single behavioural differences between egalitarian and despotic animal societies are often assumed to reflect specific adaptations. However, in the present paper, I will show in an individual-orientated model, how many behavioural traits of egalitarian and despotic virtual societies arise as emergent characteristics. The artificial entities live in a homogeneous world and only aggregate, and upon meeting one another and may perform dominance interactions in which the effects of winning and losing are self-reinforcing. The behaviour of these entities is studied in a similar way to that of real animals. It will be shown that by varying the intensity of aggression only, one may switch from egalitarian to despotic virtual societies. Differences between the two types of society appear to correspond closely to those between despotic and egalitarian macaque species in the real world. In addition, artificial despotic societies show a clearer spatial centrality of dominants and, counter-intuitively, more rank overlap between the sexes than the egalitarian ones. Because of the correspondence with patterns in real animals, the model makes it worthwhile comparing despotic and egalitarian species for socio-spatial structure and rank overlap too. Furthermore, it presents us with parsimonious hypotheses which can be tested in real animals for patterns of aggression, spatial structure and the distribution of social positive and sexual behaviour.

Pregnenolone sulphate enhances spatial orientation and object discrimination in adult male rats: evidence from a behavioural and electrophysiological study.

PubMed

Plescia, Fulvio; Sardo, Pierangelo; Rizzo, Valerio; Cacace, Silvana; Marino, Rosa Anna Maria; Brancato, Anna; Ferraro, Giuseppe; Carletti, Fabio; Cannizzaro, Carla

2014-01-01

Neurosteroids can alter neuronal excitability interacting with specific neurotransmitter receptors, thus affecting several functions such as cognition and emotionality. In this study we investigated, in adult male rats, the effects of the acute administration of pregnenolone-sulfate (PREGS) (10mg/kg, s.c.) on cognitive processes using the Can test, a non aversive spatial/visual task which allows the assessment of both spatial orientation-acquisition and object discrimination in a simple and in a complex version of the visual task. Electrophysiological recordings were also performed in vivo, after acute PREGS systemic administration in order to investigate on the neuronal activation in the hippocampus and the perirhinal cortex. Our results indicate that, PREGS induces an improvement in spatial orientation-acquisition and in object discrimination in the simple and in the complex visual task; the behavioural responses were also confirmed by electrophysiological recordings showing a potentiation in the neuronal activity of the hippocampus and the perirhinal cortex. In conclusion, this study demonstrates that PREGS systemic administration in rats exerts cognitive enhancing properties which involve both the acquisition and utilization of spatial information, and object discrimination memory, and also correlates the behavioural potentiation observed to an increase in the neuronal firing of discrete cerebral areas critical for spatial learning and object recognition. This provides further evidence in support of the role of PREGS in exerting a protective and enhancing role on human memory. Copyright © 2013. Published by Elsevier B.V.

Pathogenic landscapes: Interactions between land, people, disease vectors, and their animal hosts

PubMed Central

2010-01-01

Background Landscape attributes influence spatial variations in disease risk or incidence. We present a review of the key findings from eight case studies that we conducted in Europe and West Africa on the impact of land changes on emerging or re-emerging vector-borne diseases and/or zoonoses. The case studies concern West Nile virus transmission in Senegal, tick-borne encephalitis incidence in Latvia, sandfly abundance in the French Pyrenees, Rift Valley Fever in the Ferlo (Senegal), West Nile Fever and the risk of malaria re-emergence in the Camargue, and rodent-borne Puumala hantavirus and Lyme borreliosis in Belgium. Results We identified general principles governing landscape epidemiology in these diverse disease systems and geographic regions. We formulated ten propositions that are related to landscape attributes, spatial patterns and habitat connectivity, pathways of pathogen transmission between vectors and hosts, scale issues, land use and ownership, and human behaviour associated with transmission cycles. Conclusions A static view of the "pathogenecity" of landscapes overlays maps of the spatial distribution of vectors and their habitats, animal hosts carrying specific pathogens and their habitat, and susceptible human hosts and their land use. A more dynamic view emphasizing the spatial and temporal interactions between these agents at multiple scales is more appropriate. We also highlight the complementarity of the modelling approaches used in our case studies. Integrated analyses at the landscape scale allows a better understanding of interactions between changes in ecosystems and climate, land use and human behaviour, and the ecology of vectors and animal hosts of infectious agents. PMID:20979609

Disadvantageous associations: Reversible spatial cueing effects in a discrimination task

PubMed Central

Nico, Daniele; Daprati, Elena

2015-01-01

Current theories describe learning in terms of cognitive or associative mechanisms. To assess whether cognitive mechanisms interact with automaticity of associative processes we devised a shape-discrimination task in which participants received both explicit instructions and implicit information. Instructions further allowed for the inference that a first event would precede the target. Albeit irrelevant to respond, this event acted as response prime and implicit spatial cue (i.e. it predicted target location). To modulate cognitive involvement, in three experiments we manipulated modality and salience of the spatial cue. Results always showed evidence for a priming effect, confirming that the first stimulus was never ignored. More importantly, although participants failed to consciously recognize the association, responses to spatially cued trials became either slower or faster depending on salience of the first event. These findings provide an empirical demonstration that cognitive and associative learning mechanisms functionally co-exist and interact to regulate behaviour. PMID:26534830

Terrestrial biogeochemical cycles: global interactions with the atmosphere and hydrology

NASA Astrophysics Data System (ADS)

Schimel, David S.; Kittel, Timothy G. F.; Parton, William J.

1991-08-01

Ecosystem scientists have developed a body of theory to predict the behaviour of biogeochemical cycles when exchanges with other ecosystems are small or prescribed. Recent environmental changes make it clear that linkages between ecosystems via atmospheric and hydrological transport have large effects on ecosystem dynamics when considered over time periods of a decade to a century, time scales relevant to contemporary humankind. Our ability to predict behaviour of ecosystems coupled by transport is limited by our ability (1) to extrapolate biotic function to large spatial scales and (2) to measure and model transport. We review developments in ecosystem theory, remote sensing, and geographical information systems (GIS) that support new efforts in spatial modeling. A paradigm has emerged to predict behaviour of ecosystems based on understanding responses to multiple resources (e.g., water, nutrients, light). Several ecosystem models couple primary production to decomposition and nutrient availability using the above paradigm. These models require a fairly small set of environmental variables to simulate spatial and temporal variation in rates of biogeochemical cycling. Simultaneously, techniques for inferring ecosystem behaviour from remotely measured canopy light interception are improving our ability to infer plant activity from satellite observations. Efforts have begun to couple models of transport in air and water to models of ecosystem function. Preliminary work indicates that coupling of transport and ecosystem processes alters the behaviour of earth system components (hydrology, terrestrial ecosystems, and the atmosphere) from that of an uncoupled mode.

Physiology modulates social flexibility and collective behaviour in equids and other large ungulates.

PubMed

Gersick, Andrew S; Rubenstein, Daniel I

2017-08-19

Though morphologically very similar, equids across the extant species occupy ecological niches that are surprisingly non-overlapping. Occupancy of these distinct niches appears related to subtle physiological and behavioural adaptations which, in turn, correspond to significant differences in the social behaviours and emergent social systems characterizing the different species. Although instances of intraspecific behavioural variation in equids demonstrate that the same body plan can support a range of social structures, each of these morphologically similar species generally shows robust fidelity to its evolved social system. The pattern suggests a subtle relationship between physiological phenotypes and behavioural flexibility. While environmental conditions can vary widely within relatively short temporal or spatial scales, physiological changes and changes to the behaviours that regulate physiological processes, are constrained to longer cycles of adaptation. Physiology is then the limiting variable in the interaction between ecological variation and behavioural and socio-structural flexibility. Behavioural and socio-structural flexibility, in turn, will generate important feedbacks that will govern physiological function, thus creating a coupled web of interactions that can lead to changes in individual and collective behaviour. Longitudinal studies of equid and other large-bodied ungulate populations under environmental stress, such as those discussed here, may offer the best opportunities for researchers to examine, in real time, the interplay between individual behavioural plasticity, socio-structural flexibility, and the physiological and genetic changes that together produce adaptive change.This article is part of the themed issue 'Physiological determinants of social behaviour in animals'. © 2017 The Author(s).

When the going gets tough: behavioural type-dependent space use in the sleepy lizard changes as the season dries

PubMed Central

Spiegel, Orr; Leu, Stephan T.; Sih, Andrew; Godfrey, Stephanie S.; Bull, C. Michael

2015-01-01

Understanding space use remains a major challenge for animal ecology, with implications for species interactions, disease spread, and conservation. Behavioural type (BT) may shape the space use of individuals within animal populations. Bolder or more aggressive individuals tend to be more exploratory and disperse further. Yet, to date we have limited knowledge on how space use other than dispersal depends on BT. To address this question we studied BT-dependent space-use patterns of sleepy lizards (Tiliqua rugosa) in southern Australia. We combined high-resolution global positioning system (GPS) tracking of 72 free-ranging lizards with repeated behavioural assays, and with a survey of the spatial distributions of their food and refuge resources. Bayesian generalized linear mixed models (GLMM) showed that lizards responded to the spatial distribution of resources at the neighbourhood scale and to the intensity of space use by other conspecifics (showing apparent conspecific avoidance). BT (especially aggressiveness) affected space use by lizards and their response to ecological and social factors, in a seasonally dependent manner. Many of these effects and interactions were stronger later in the season when food became scarce and environmental conditions got tougher. For example, refuge and food availability became more important later in the season and unaggressive lizards were more responsive to these predictors. These findings highlight a commonly overlooked source of heterogeneity in animal space use and improve our mechanistic understanding of processes leading to behaviourally driven disease dynamics and social structure. PMID:26609082

Social structure of collared peccaries (Pecari tajacu): does relatedness matter?

PubMed

Biondo, Cibele; Izar, Patrícia; Miyaki, Cristina Y; Bussab, Vera S R

2014-11-01

Relatedness is considered an important factor in shaping social structure as the association among kin might facilitate cooperation via inclusive fitness benefits. We addressed here the influence of relatedness on the social structure of a Neotropical ungulate, the collared peccary (Pecari tajacu). As peccaries are highly social and cooperative, live in stable cohesive herds and show certain degree of female philopatry and high mean relatedness within herds, we hypothesized that kin would be spatially closer and display more amicable and less agonistic interactions than non-kin. We recorded spatial association patterns and rates of interactions of two captive groups. Pairwise relatedness was calculated based on microsatellite data. As predicted, we found that kin were spatially closer than non-kin, which suggests that relatedness is a good predictor of spatial association in peccaries. However, relatedness did not predict the rates of social interactions. Although our results indirectly indicate some role of sex, age and familiarity, further studies are needed to clarify the factors that shape the rates of interactions in collared peccaries. This article is part of a Special Issue entitled: Neotropical Behaviour. Copyright © 2014 Elsevier B.V. All rights reserved.

Spatial constancy mechanisms in motor control

PubMed Central

Medendorp, W. Pieter

2011-01-01

The success of the human species in interacting with the environment depends on the ability to maintain spatial stability despite the continuous changes in sensory and motor inputs owing to movements of eyes, head and body. In this paper, I will review recent advances in the understanding of how the brain deals with the dynamic flow of sensory and motor information in order to maintain spatial constancy of movement goals. The first part summarizes studies in the saccadic system, showing that spatial constancy is governed by a dynamic feed-forward process, by gaze-centred remapping of target representations in anticipation of and across eye movements. The subsequent sections relate to other oculomotor behaviour, such as eye–head gaze shifts, smooth pursuit and vergence eye movements, and their implications for feed-forward mechanisms for spatial constancy. Work that studied the geometric complexities in spatial constancy and saccadic guidance across head and body movements, distinguishing between self-generated and passively induced motion, indicates that both feed-forward and sensory feedback processing play a role in spatial updating of movement goals. The paper ends with a discussion of the behavioural mechanisms of spatial constancy for arm motor control and their physiological implications for the brain. Taken together, the emerging picture is that the brain computes an evolving representation of three-dimensional action space, whose internal metric is updated in a nonlinear way, by optimally integrating noisy and ambiguous afferent and efferent signals. PMID:21242137

Hippocampal-prefrontal input supports spatial encoding in working memory.

PubMed

Spellman, Timothy; Rigotti, Mattia; Ahmari, Susanne E; Fusi, Stefano; Gogos, Joseph A; Gordon, Joshua A

2015-06-18

Spatial working memory, the caching of behaviourally relevant spatial cues on a timescale of seconds, is a fundamental constituent of cognition. Although the prefrontal cortex and hippocampus are known to contribute jointly to successful spatial working memory, the anatomical pathway and temporal window for the interaction of these structures critical to spatial working memory has not yet been established. Here we find that direct hippocampal-prefrontal afferents are critical for encoding, but not for maintenance or retrieval, of spatial cues in mice. These cues are represented by the activity of individual prefrontal units in a manner that is dependent on hippocampal input only during the cue-encoding phase of a spatial working memory task. Successful encoding of these cues appears to be mediated by gamma-frequency synchrony between the two structures. These findings indicate a critical role for the direct hippocampal-prefrontal afferent pathway in the continuous updating of task-related spatial information during spatial working memory.

Herbivore-induced plant volatiles and tritrophic interactions across spatial scales.

PubMed

Aartsma, Yavanna; Bianchi, Felix J J A; van der Werf, Wopke; Poelman, Erik H; Dicke, Marcel

2017-12-01

Herbivore-induced plant volatiles (HIPVs) are an important cue used in herbivore location by carnivorous arthropods such as parasitoids. The effects of plant volatiles on parasitoids have been well characterised at small spatial scales, but little research has been done on their effects at larger spatial scales. The spatial matrix of volatiles ('volatile mosaic') within which parasitoids locate their hosts is dynamic and heterogeneous. It is shaped by the spatial pattern of HIPV-emitting plants, the concentration, chemical composition and breakdown of the emitted HIPV blends, and by environmental factors such as wind, turbulence and vegetation that affect transport and mixing of odour plumes. The volatile mosaic may be exploited differentially by different parasitoid species, in relation to species traits such as sensory ability to perceive volatiles and the physical ability to move towards the source. Understanding how HIPVs influence parasitoids at larger spatial scales is crucial for our understanding of tritrophic interactions and sustainable pest management in agriculture. However, there is a large gap in our knowledge on how volatiles influence the process of host location by parasitoids at the landscape scale. Future studies should bridge the gap between the chemical and behavioural ecology of tritrophic interactions and landscape ecology. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

The interaction between water currents and salmon swimming behaviour in sea cages.

PubMed

Johansson, David; Laursen, Frida; Fernö, Anders; Fosseidengen, Jan Erik; Klebert, Pascal; Stien, Lars Helge; Vågseth, Tone; Oppedal, Frode

2014-01-01

Positioning of sea cages at sites with high water current velocities expose the fish to a largely unknown environmental challenge. In this study we observed the swimming behaviour of Atlantic salmon (Salmo salar L.) at a commercial farm with tidal currents altering between low, moderate and high velocities. At high current velocities the salmon switched from the traditional circular polarized group structure, seen at low and moderate current velocities, to a group structure where all fish kept stations at fixed positions swimming against the current. This type of group behaviour has not been described in sea cages previously. The structural changes could be explained by a preferred swimming speed of salmon spatially restricted in a cage in combination with a behavioural plasticity of the fish.

Mechanical behaviour near grain boundaries of He-implanted UO2 ceramic polycrystals

NASA Astrophysics Data System (ADS)

Ibrahim, M.; Castelier, É.; Palancher, H.; Bornert, M.; Caré, S.; Micha, J.-S.

2017-01-01

For studying the micromechanical behaviour of UO2 and characterising the intergranular interaction, polycrystals are implanted with helium ions, inducing strains in a thin surface layer. Laue X-ray micro-diffraction is used to measure the strain field in this implanted layer with a spatial resolution of about 1 μm. It allows a 2D mapping of the strain field in a dozen of grains. These measurements show that the induced strain depends mainly on the crystal orientation, and can be evaluated by a semi-analytical mechanical model. A mechanical interaction of the neighbouring grains has also been evidenced near the grain boundaries, which has been well reproduced by a finite element model. This interaction is shown to increase with the implantation energy (i.e. the implantation depth): it can be neglected at low implantation energy (60 keV), but not at higher energy (500 keV).

When the going gets tough: behavioural type-dependent space use in the sleepy lizard changes as the season dries.

PubMed

Spiegel, Orr; Leu, Stephan T; Sih, Andrew; Godfrey, Stephanie S; Bull, C Michael

2015-11-22

Understanding space use remains a major challenge for animal ecology, with implications for species interactions, disease spread, and conservation. Behavioural type (BT) may shape the space use of individuals within animal populations. Bolder or more aggressive individuals tend to be more exploratory and disperse further. Yet, to date we have limited knowledge on how space use other than dispersal depends on BT. To address this question we studied BT-dependent space-use patterns of sleepy lizards (Tiliqua rugosa) in southern Australia. We combined high-resolution global positioning system (GPS) tracking of 72 free-ranging lizards with repeated behavioural assays, and with a survey of the spatial distributions of their food and refuge resources. Bayesian generalized linear mixed models (GLMM) showed that lizards responded to the spatial distribution of resources at the neighbourhood scale and to the intensity of space use by other conspecifics (showing apparent conspecific avoidance). BT (especially aggressiveness) affected space use by lizards and their response to ecological and social factors, in a seasonally dependent manner. Many of these effects and interactions were stronger later in the season when food became scarce and environmental conditions got tougher. For example, refuge and food availability became more important later in the season and unaggressive lizards were more responsive to these predictors. These findings highlight a commonly overlooked source of heterogeneity in animal space use and improve our mechanistic understanding of processes leading to behaviourally driven disease dynamics and social structure. © 2015 The Author(s).

Ecological implications of behavioural syndromes.

PubMed

Sih, Andrew; Cote, Julien; Evans, Mara; Fogarty, Sean; Pruitt, Jonathan

2012-03-01

Interspecific trait variation has long served as a conceptual foundation for our understanding of ecological patterns and dynamics. In particular, ecologists recognise the important role that animal behaviour plays in shaping ecological processes. An emerging area of interest in animal behaviour, the study of behavioural syndromes (animal personalities) considers how limited behavioural plasticity, as well as behavioural correlations affects an individual's fitness in diverse ecological contexts. In this article we explore how insights from the concept and study of behavioural syndromes provide fresh understanding of major issues in population ecology. We identify several general mechanisms for how population ecology phenomena can be influenced by a species or population's average behavioural type, by within-species variation in behavioural type, or by behavioural correlations across time or across ecological contexts. We note, in particular, the importance of behavioural type-dependent dispersal in spatial ecology. We then review recent literature and provide new syntheses for how these general mechanisms produce novel insights on five major issues in population ecology: (1) limits to species' distribution and abundance; (2) species interactions; (3) population dynamics; (4) relative responses to human-induced rapid environmental change; and (5) ecological invasions. © 2012 Blackwell Publishing Ltd/CNRS.

Children with Prader-Willi syndrome vs. Williams syndrome: indirect effects on parents during a jigsaw puzzle task.

PubMed

Ly, T M; Hodapp, R M

2005-12-01

Genetic disorders predispose individuals to exhibit characteristic behaviours, which in turn elicit particular behaviours from others. In response to the strength of Prader-Willi syndrome (PWS) and weakness of Williams syndrome (WS) in visual-spatial tasks such as jigsaw puzzles, parents' behaviours can be affected by their child's level of puzzle ability or syndrome diagnosis. Children were asked to complete two jigsaw puzzles (one with the experimenter and the other with the parent) for 5 min each. Frequencies of parental helping and reinforcement behaviours, along with ratings of parental directiveness, were examined as parents interacted with their children on a jigsaw puzzle task. Within each aetiological group, correlates of parental behaviours with child characteristics were also examined. Compared to parents of children with PWS, parents of children with WS engaged in a more directive style of interaction, and provided more help and reinforcement. Relative to parents of children with higher puzzle abilities (from both aetiologies), parents of children with lower abilities also showed the same pattern. Both the child's aetiology and puzzle abilities were important in predicting parents' directiveness and helping and reinforcement behaviours. Within the PWS group, parents' behaviours correlated negatively with the child's puzzle abilities and general cognitive functioning; no such relations occurred in the WS group. Parents' behaviours were affected by both the child's diagnosis and actual puzzle abilities, suggesting important implications for understanding and intervening with parents and children with different genetic syndromes.

An Individual-Oriented Model on the Emergence of Support in Fights, Its Reciprocation and Exchange

PubMed Central

Hemelrijk, Charlotte K.; Puga-Gonzalez, Ivan

2012-01-01

Complex social behaviour of primates has usually been attributed to the operation of complex cognition. Recently, models have shown that constraints imposed by the socio-spatial structuring of individuals in a group may result in an unexpectedly high number of patterns of complex social behaviour, resembling the dominance styles of egalitarian and despotic species of macaques and the differences between them. This includes affiliative patterns, such as reciprocation of grooming, grooming up the hierarchy, and reconciliation. In the present study, we show that the distribution of support in fights, which is the social behaviour that is potentially most sophisticated in terms of cognitive processes, may emerge in the same way. The model represents the spatial grouping of individuals and their social behaviour, such as their avoidance of risks during attacks, the self-reinforcing effects of winning and losing their fights, their tendency to join in fights of others that are close by (social facilitation), their tendency to groom when they are anxious, the reduction of their anxiety by grooming, and the increase of anxiety when involved in aggression. Further, we represent the difference in intensity of aggression apparent in egalitarian and despotic macaques. The model reproduces many aspects of support in fights, such as its different types, namely, conservative, bridging and revolutionary, patterns of choice of coalition partners attributed to triadic awareness, those of reciprocation of support and ‘spiteful acts’ and of exchange between support and grooming. This work is important because it suggests that behaviour that seems to result from sophisticated cognition may be a side-effect of spatial structure and dominance interactions and it shows that partial correlations fail to completely omit these effects of spatial structure. Further, the model is falsifiable, since it results in many patterns that can easily be tested in real primates by means of existing data. PMID:22666348

Heart rate modulation in bystanding geese watching social and non-social events

PubMed Central

Wascher, Claudia A.F; Scheiber, Isabella B.R; Kotrschal, Kurt

2008-01-01

Simply observing other individuals interacting has been shown to affect subsequent behaviour and also hormones in ‘bystander’ individuals. However, immediate physiological responses of an observer have been hardly investigated. Here we present results on individuals' heart rate (HR) responses during various situations, which occur regularly in a flock of greylag geese (Anser anser, e.g. agonistic encounters, vehicles passing by). We recorded simultaneously HR and behaviour of 21 semi-tame free-roaming geese, equipped with fully implanted transmitters. We considered 304 social and 81 non-social events during which the focal individuals did not respond behaviourally. Independent of the spatial distance to the event, these HR responses were significantly greater in social contexts (e.g. departing or landing geese, agonistic interactions) than in non-social situations (e.g. vehicles passing by, thunder). Focal individuals showed a significantly higher maximum HR as well as a greater HR increase in response to agonistic interactions, in which the pair partner or a family member was involved, as compared with a non-affiliated goose. Also, HR was significantly higher when the bystander watched non-affiliated geese interacting, which were higher ranking than the focal. We conclude that these differences are due to different relevance of the recorded events for the focal individual, depending on the individuals involved in the observed interaction. PMID:18430645

Forest fire spatial pattern analysis in Galicia (NW Spain).

PubMed

Fuentes-Santos, I; Marey-Pérez, M F; González-Manteiga, W

2013-10-15

Knowledge of fire behaviour is of key importance in forest management. In the present study, we analysed the spatial structure of forest fire with spatial point pattern analysis and inference techniques recently developed in the Spatstat package of R. Wildfires have been the primary threat to Galician forests in recent years. The district of Fonsagrada-Ancares is one of the most seriously affected by fire in the region and, therefore, the central focus of the study. Our main goal was to determine the spatial distribution of ignition points to model and predict fire occurrence. These data are of great value in establishing enhanced fire prevention and fire fighting plans. We found that the spatial distribution of wildfires is not random and that fire occurrence may depend on ownership conflicts. We also found positive interaction between small and large fires and spatial independence between wildfires in consecutive years. Copyright © 2013 Elsevier Ltd. All rights reserved.

Spatial Dependence and Determinants of Dairy Farmers' Adoption of Best Management Practices for Water Protection in New Zealand

NASA Astrophysics Data System (ADS)

Yang, Wei; Sharp, Basil

2017-04-01

This paper analyses spatial dependence and determinants of the New Zealand dairy farmers' adoption of best management practices to protect water quality. A Bayesian spatial durbin probit model is used to survey data collected from farmers in the Waikato region of New Zealand. The results show that farmers located near each other exhibit similar choice behaviour, indicating the importance of farmer interactions in adoption decisions. The results also address that information acquisition is the most important determinant of farmers' adoption of best management practices. Financial problems are considered a significant barrier to adopting best management practices. Overall, the existence of distance decay effect and spatial dependence in farmers' adoption decisions highlights the importance of accounting for spatial effects in farmers' decision-making, which emerges as crucial to the formulation of sustainable agriculture policy.

Spatial Dependence and Determinants of Dairy Farmers' Adoption of Best Management Practices for Water Protection in New Zealand.

PubMed

Yang, Wei; Sharp, Basil

2017-04-01

This paper analyses spatial dependence and determinants of the New Zealand dairy farmers' adoption of best management practices to protect water quality. A Bayesian spatial durbin probit model is used to survey data collected from farmers in the Waikato region of New Zealand. The results show that farmers located near each other exhibit similar choice behaviour, indicating the importance of farmer interactions in adoption decisions. The results also address that information acquisition is the most important determinant of farmers' adoption of best management practices. Financial problems are considered a significant barrier to adopting best management practices. Overall, the existence of distance decay effect and spatial dependence in farmers' adoption decisions highlights the importance of accounting for spatial effects in farmers' decision-making, which emerges as crucial to the formulation of sustainable agriculture policy.

The evolution of parasite manipulation of host dispersal

PubMed Central

Lion, Sébastien; van Baalen, Minus; Wilson, William G

2006-01-01

We investigate the evolution of manipulation of host dispersal behaviour by parasites using spatially explicit individual-based simulations. We find that when dispersal is local, parasites always gain from increasing their hosts' dispersal rate, although the evolutionary outcome is determined by the costs-to-benefits ratio. However, when dispersal can be non-local, we show that parasites investing in an intermediate dispersal distance of their hosts are favoured even when the manipulation is not costly, due to the intrinsic spatial dynamics of the host–parasite interaction. Our analysis highlights the crucial importance of ecological spatial dynamics in evolutionary processes and reveals the theoretical possibility that parasites could manipulate their hosts' dispersal. PMID:16600882

Theoretical studies to elucidate the influence of magnetic dipolar interactions occurring in the magnetic nanoparticle systems, for biomedical applications

NASA Astrophysics Data System (ADS)

Osaci, M.; Cacciola, M.

2016-02-01

In recent years, the study of magnetic nanoparticles has been intensively developed not only for their fundamental theoretical interest, but also for their many technological applications, especially biomedical applications, ranging from contrast agents for magnetic resonance imaging to the deterioration of cancer cells via hyperthermia treatment. The theoretical and experimental research has shown until now that the magnetic dipolar interactions between nanoparticles can have a significant influence on the magnetic behaviour of the system. But, this influence is not well understood. It is clear that the magnetic dipolar interaction intensity is correlated with the nanoparticle concentration, volume fraction and magnetic moment orientations. In this paper, we try to understand the influence of magnetic dipolar interactions on the behaviour of magnetic nanoparticle systems, for biomedical applications. For the model, we considered spherical nanoparticles with uniaxial anisotropy and lognormal distribution of the sizes. The model involves a simulation stage of the spatial distribution and orientation of the nanoparticles and their easy axes of magnetic anisotropy, and an evaluation stage of the Néel relaxation time. To assess the Néel relaxation time, we are going to discretise and adapt, to the local magnetic field, the Coffey analytical solution for the equation Fokker-Planck describing the dynamics of magnetic moments of nanoparticles in oblique external magnetic field. There are three fundamental aspects of interest in our studies on the magnetic nanoparticles: their spatial & orientational distributions, concentrations and sizes.

Driving magnetic turbulence using flux ropes in a moderate guide field linear system

NASA Astrophysics Data System (ADS)

Brookhart, Matthew I.; Stemo, Aaron; Waleffe, Roger; Forest, Cary B.

2017-12-01

We present a series of experiments on novel, line-tied plasma geometries as a study of the generation of chaos and turbulence in line-tied systems. Plasma production and the injection scale for magnetic energy is provided by spatially discrete plasma guns that inject both plasma and current. The guns represent a technique for controlling the injection scale of magnetic energy. A two-dimensional (2-D) array of magnetic probes provides spatially resolved time histories of the magnetic fluctuations at a single cross-section of the experimental cylinder, allowing simultaneous spatial measurements of chaotic and turbulent behaviour. The first experiment shows chaotic fluctuations and self-organization in a hollow-current line-tied screw pinch. These dynamics is modulated primarily by the applied magnetic field and weakly by the plasma current and safety factor. The second experiment analyses the interactions of multiple line-tied flux ropes. The flux ropes all exhibit chaotic behaviour, and under certain conditions develop an inverse cascade to larger scales and a turbulent inertial range with magnetic energy ( ) related to perpendicular wave number ( \\bot $ ) as \\bot -2.5\\pm 0.5$ .

Polymorphic mimicry, microhabitat use, and sex-specific behaviour.

PubMed

Joron, M

2005-05-01

In order to assess the adaptive importance of microhabitat segregation for the maintenance of mimetic diversity, I explore how flight height varies between the sympatric forms of the polymorphic butterfly Heliconius numata and their respective models in the genus Melinaea. There is no evidence for vertical stratification of mimicry rings in these tiger-patterned butterflies, but males of H. numata tend to fly significantly higher than females and the Melinaea models. This difference in microhabitat preference likely results from females searching for host plants whereas males are patrolling for mates. I then present an extension of Muller's mimicry model for the case of partial behavioural or spatial segregation of sexes. The analysis suggests that sex-specific behaviours can make mimicry more beneficial, simply by reducing the effective population size participating in mimicry. The interaction between mimicry and sex-specific behaviours may therefore facilitate the evolution of polymorphism via enhanced, fine-scale local adaptation.

Effects of dipolar interactions in magnetic nanoparticle systems

NASA Astrophysics Data System (ADS)

Ruta, Sergiu; Hovorka, Ondrej; Chantrell, Roy

2014-03-01

Understanding the effects of magnetostatic interactions in magnetic nanoparticle systems is of importance in magnetic recording, biomedical applications such as in hyperthermia cancer treatment, or for sensing approaches in biology and chemistry, for example. In this talk we discuss the macroscopic and microscopic effects of dipole-dipole interactions in three-dimensional assemblies of magnetic nanoparticles in various spatial arrangements, including the BCC, FCC, or randomized lattices. Our study is based on the kinetic Monte-Carlo modelling and concentrates on exploring the effect of the particle arrangement, distributions of particle volumes and anisotropy axes, and the role of thermal effects on the overall behaviour of hysteresis loops, ZFC/FC temperature scans and the magnetization decay data computed during the relaxation to equilibrium. In the case of the FCC lattice we find a counter-intuitive effect where increasing the interaction strength enhances/suppresses the hysteresis loop coercivity at high/low temperatures. The analysis of the domain pattern formation and pair correlation functions suggests for the observed behaviour to be a result of the phenomenon of frustration. We also discuss the possibility of observing the super-ferromagnetic phases on similar syste

Collective behaviour in vertebrates: a sensory perspective

PubMed Central

Collignon, Bertrand; Fernández-Juricic, Esteban

2016-01-01

Collective behaviour models can predict behaviours of schools, flocks, and herds. However, in many cases, these models make biologically unrealistic assumptions in terms of the sensory capabilities of the organism, which are applied across different species. We explored how sensitive collective behaviour models are to these sensory assumptions. Specifically, we used parameters reflecting the visual coverage and visual acuity that determine the spatial range over which an individual can detect and interact with conspecifics. Using metric and topological collective behaviour models, we compared the classic sensory parameters, typically used to model birds and fish, with a set of realistic sensory parameters obtained through physiological measurements. Compared with the classic sensory assumptions, the realistic assumptions increased perceptual ranges, which led to fewer groups and larger group sizes in all species, and higher polarity values and slightly shorter neighbour distances in the fish species. Overall, classic visual sensory assumptions are not representative of many species showing collective behaviour and constrain unrealistically their perceptual ranges. More importantly, caution must be exercised when empirically testing the predictions of these models in terms of choosing the model species, making realistic predictions, and interpreting the results. PMID:28018616

Spatial Heterogeneity in the Strength of Plant-Herbivore Interactions under Predation Risk: The Tale of Bison Foraging in Wolf Country

PubMed Central

Harvey, Léa; Fortin, Daniel

2013-01-01

Spatial heterogeneity in the strength of trophic interactions is a fundamental property of food web spatial dynamics. The feeding effort of herbivores should reflect adaptive decisions that only become rewarding when foraging gains exceed 1) the metabolic costs, 2) the missed opportunity costs of not foraging elsewhere, and 3) the foraging costs of anti-predator behaviour. Two aspects of these costs remain largely unexplored: the link between the strength of plant-herbivore interactions and the spatial scale of food-quality assessment, and the predator-prey spatial game. We modeled the foraging effort of free-ranging plains bison (Bison bison bison) in winter, within a mosaic of discrete meadows. Spatial patterns of bison herbivory were largely driven by a search for high net energy gains and, to a lesser degree, by the spatial game with grey wolves (Canis lupus). Bison decreased local feeding effort with increasing metabolic and missed opportunity costs. Bison herbivory was most consistent with a broad-scale assessment of food patch quality, i.e., bison grazed more intensively in patches with a low missed opportunity cost relative to other patches available in the landscape. Bison and wolves had a higher probability of using the same meadows than expected randomly. This co-occurrence indicates wolves are ahead in the spatial game they play with bison. Wolves influenced bison foraging at fine scale, as bison tended to consume less biomass at each feeding station when in meadows where the risk of a wolf's arrival was relatively high. Also, bison left more high-quality vegetation in large than small meadows. This behavior does not maximize their energy intake rate, but is consistent with bison playing a shell game with wolves. Our assessment of bison foraging in a natural setting clarifies the complex nature of plant-herbivore interactions under predation risk, and reveals how spatial patterns in herbivory emerge from multi-scale landscape heterogeneity. PMID:24039909

Shear-induced orientational dynamics and spatial heterogeneity in suspensions of motile phytoplankton

PubMed Central

Barry, Michael T.; Rusconi, Roberto; Guasto, Jeffrey S.; Stocker, Roman

2015-01-01

Fluid flow, ubiquitous in natural and man-made environments, has the potential to profoundly impact the transport of microorganisms, including phytoplankton in aquatic habitats and bioreactors. Yet, the effect of ambient flow on the swimming behaviour of phytoplankton has remained poorly understood, largely owing to the difficulty of observing cell–flow interactions at the microscale. Here, we present microfluidic experiments where we tracked individual cells for four species of motile phytoplankton exposed to a spatially non-uniform fluid shear rate, characteristic of many flows in natural and artificial environments. We observed that medium-to-high mean shear rates (1–25 s−1) produce heterogeneous cell concentrations in the form of regions of accumulation and regions of depletion. The location of these regions relative to the flow depends on the cells' propulsion mechanism, body shape and flagellar arrangement, as captured by an effective aspect ratio. Species having a large effective aspect ratio accumulated in the high-shear regions, owing to shear-induced alignment of the swimming orientation with the fluid streamlines. Species having an effective aspect ratio close to unity exhibited little preferential accumulation at low-to-moderate flow rates, but strongly accumulated in the low-shear regions under high flow conditions, potentially owing to an active, behavioural response of cells to shear. These observations demonstrate that ambient fluid flow can strongly affect the motility and spatial distribution of phytoplankton and highlight the rich dynamics emerging from the interaction between motility, morphology and flow. PMID:26538558

Head rubbing and licking reinforce social bonds in a group of captive African lions, Panthera leo.

PubMed

Matoba, Tomoyuki; Kutsukake, Nobuyuki; Hasegawa, Toshikazu

2013-01-01

Many social animals have a species-specific repertoire of affiliative behaviours that characterise individualised relationships within a group. To date, however, quantitative studies on intragroup affiliative behaviours in social carnivores have been limited. Here, we investigated the social functions of the two most commonly observed affiliative behaviours in captive African lions (Panthera leo): head rubbing and licking. We conducted behavioural observations on a captive group of lions composed of 7 males and 14 females, and tested hypotheses regarding three social functions: tension reduction, social bonding, and social status expression. Disproportionately frequent male-male and female-to-male head rubbing was observed, while more than 95% of all licking interactions occurred in female-female dyads. In accordance with the social bond hypothesis, and in disagreement with the social status expression hypothesis, both head rubbing and licking interactions were reciprocal. After controlling for spatial association, the dyadic frequency of head rubbing was negatively correlated with age difference while licking was positively correlated with relatedness. Group reunion after daily separation did not affect the frequencies of the affiliative behaviours, which was in disagreement with the predictions from the tension reduction hypothesis. These results support the social bond hypothesis for the functions of head rubbing and licking. Different patterns of affiliative behaviour between the sexes may reflect differences in the relationship quality in each sex or the differential predisposition to licking due to its original function in offspring care.

Behavioural study of two hydrothermal crustacean decapods: Mirocaris fortunata and Segonzacia mesatlantica, from the Lucky Strike vent field (Mid-Atlantic Ridge)

NASA Astrophysics Data System (ADS)

Matabos, M.; Cuvelier, D.; Brouard, J.; Shillito, B.; Ravaux, J.; Zbinden, M.; Barthelemy, D.; Sarradin, P. M.; Sarrazin, J.

2015-11-01

Identifying the factors driving community dynamics in hydrothermal vent communities, and in particular biological interactions, is challenged by our ability to make direct observations and the difficulty to conduct experiments in those remote ecosystems. As a result, we have very limited knowledge on species' behaviour and interactions in these communities and how they in turn influence community dynamics. Interactions such as competition or predation significantly affect community structure in vent communities, and video time-series have successfully been used to gain insights in biological interactions and species behaviour, including responses to short-term changes in temperature or feeding strategies. In this study, we combined in situ and ex situ approaches to characterise the behaviour and interactions among two key species encountered along the Mid-Atlantic Ridge (MAR): the shrimp Mirocaris fortunata and the crab Segonzacia mesatlantica. In situ, species small-scale distribution, interactions and behaviour were studied using the TEMPO observatory module deployed on the seafloor at the base of the active Eiffel Tower edifice in the Lucky Strike vent field as part of the EMSO-Açores MoMAR observatory. TEMPO sampled 2 min of video four times a day from July 2011 to April 2012. One week of observations per month was used for 'long-term' variations, and a full video data set was analysed for January 2012. In addition, observations of crab and shrimp individuals maintained for the first time under controlled conditions in atmospheric pressure (classic tank) and pressurised (AbyssBox) aquaria allowed better characterisation and description of the different types of behaviour and interactions observed in nature. While the identified in situ spatial distribution pattern was stable over the nine months, both species displayed a significant preference for mussel bed and anhydrite substrata, and preferentially occupied the area located directly in the fluid flow axis. The aggregation behaviour of M. fortunata resulted in the occurrence of numerous intraspecific interactions mainly involving the use of two pairs of sensory organs (antenna/antennule) and fleeing behaviours when in contact or close to individuals of S. mesatlantica. The higher level of passiveness observed in the ex situ artificial environment compared to the in situ environment was attributed to the lack of stimulation related to low densities of congeners and/or of sympatric species compared to the natural environment and the absence of continuous food supply, as both species displayed a significant higher level of activity during feeding time. This result emphasises the role of food supply as a driver of species distribution and behaviour. Direct in situ observations using cameras deployed on deep-sea observatories, combined with experimental set-up in pressurised aquaria, will help investigators understand the factors influencing community dynamics and species biology at vents as well as their underlying mechanisms.

Disorder-mediated crowd control in an active matter system

NASA Astrophysics Data System (ADS)

Pinçe, Erçağ; Velu, Sabareesh K. P.; Callegari, Agnese; Elahi, Parviz; Gigan, Sylvain; Volpe, Giovanni; Volpe, Giorgio

2016-03-01

Living active matter systems such as bacterial colonies, schools of fish and human crowds, display a wealth of emerging collective and dynamic behaviours as a result of far-from-equilibrium interactions. The dynamics of these systems are better understood and controlled considering their interaction with the environment, which for realistic systems is often highly heterogeneous and disordered. Here, we demonstrate that the presence of spatial disorder can alter the long-term dynamics in a colloidal active matter system, making it switch between gathering and dispersal of individuals. At equilibrium, colloidal particles always gather at the bottom of any attractive potential; however, under non-equilibrium driving forces in a bacterial bath, the colloids disperse if disorder is added to the potential. The depth of the local roughness in the environment regulates the transition between gathering and dispersal of individuals in the active matter system, thus inspiring novel routes for controlling emerging behaviours far from equilibrium.

Autistic-like behaviour in Scn1a+/- mice and rescue by enhanced GABA-mediated neurotransmission.

PubMed

Han, Sung; Tai, Chao; Westenbroek, Ruth E; Yu, Frank H; Cheah, Christine S; Potter, Gregory B; Rubenstein, John L; Scheuer, Todd; de la Iglesia, Horacio O; Catterall, William A

2012-09-20

Haploinsufficiency of the SCN1A gene encoding voltage-gated sodium channel Na(V)1.1 causes Dravet's syndrome, a childhood neuropsychiatric disorder including recurrent intractable seizures, cognitive deficit and autism-spectrum behaviours. The neural mechanisms responsible for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome are poorly understood. Here we report that mice with Scn1a haploinsufficiency exhibit hyperactivity, stereotyped behaviours, social interaction deficits and impaired context-dependent spatial memory. Olfactory sensitivity is retained, but novel food odours and social odours are aversive to Scn1a(+/-) mice. GABAergic neurotransmission is specifically impaired by this mutation, and selective deletion of Na(V)1.1 channels in forebrain interneurons is sufficient to cause these behavioural and cognitive impairments. Remarkably, treatment with low-dose clonazepam, a positive allosteric modulator of GABA(A) receptors, completely rescued the abnormal social behaviours and deficits in fear memory in the mouse model of Dravet's syndrome, demonstrating that they are caused by impaired GABAergic neurotransmission and not by neuronal damage from recurrent seizures. These results demonstrate a critical role for Na(V)1.1 channels in neuropsychiatric functions and provide a potential therapeutic strategy for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome.

Repeatability of circadian behavioural variation revealed in free-ranging marine fish.

PubMed

Alós, Josep; Martorell-Barceló, Martina; Campos-Candela, Andrea

2017-02-01

Repeatable between-individual differences in the behavioural manifestation of underlying circadian rhythms determine chronotypes in humans and terrestrial animals. Here, we have repeatedly measured three circadian behaviours, awakening time, rest onset and rest duration, in the free-ranging pearly razorfish, Xyrithchys novacula , facilitated by acoustic tracking technology and hidden Markov models. In addition, daily travelled distance, a standard measure of daily activity as fish personality trait, was repeatedly assessed using a State-Space Model. We have decomposed the variance of these four behavioural traits using linear mixed models and estimated repeatability scores ( R ) while controlling for environmental co-variates: year of experimentation, spatial location of the activity, fish size and gender and their interactions. Between- and within-individual variance decomposition revealed significant R s in all traits suggesting high predictability of individual circadian behavioural variation and the existence of chronotypes. The decomposition of the correlations among chronotypes and the personality trait studied here into between- and within-individual correlations did not reveal any significant correlation at between-individual level. We therefore propose circadian behavioural variation as an independent axis of the fish personality, and the study of chronotypes and their consequences as a novel dimension in understanding within-species fish behavioural diversity.

Visual Benefits in Apparent Motion Displays: Automatically Driven Spatial and Temporal Anticipation Are Partially Dissociated

PubMed Central

Ahrens, Merle-Marie; Veniero, Domenica; Gross, Joachim; Harvey, Monika; Thut, Gregor

2015-01-01

Many behaviourally relevant sensory events such as motion stimuli and speech have an intrinsic spatio-temporal structure. This will engage intentional and most likely unintentional (automatic) prediction mechanisms enhancing the perception of upcoming stimuli in the event stream. Here we sought to probe the anticipatory processes that are automatically driven by rhythmic input streams in terms of their spatial and temporal components. To this end, we employed an apparent visual motion paradigm testing the effects of pre-target motion on lateralized visual target discrimination. The motion stimuli either moved towards or away from peripheral target positions (valid vs. invalid spatial motion cueing) at a rhythmic or arrhythmic pace (valid vs. invalid temporal motion cueing). Crucially, we emphasized automatic motion-induced anticipatory processes by rendering the motion stimuli non-predictive of upcoming target position (by design) and task-irrelevant (by instruction), and by creating instead endogenous (orthogonal) expectations using symbolic cueing. Our data revealed that the apparent motion cues automatically engaged both spatial and temporal anticipatory processes, but that these processes were dissociated. We further found evidence for lateralisation of anticipatory temporal but not spatial processes. This indicates that distinct mechanisms may drive automatic spatial and temporal extrapolation of upcoming events from rhythmic event streams. This contrasts with previous findings that instead suggest an interaction between spatial and temporal attention processes when endogenously driven. Our results further highlight the need for isolating intentional from unintentional processes for better understanding the various anticipatory mechanisms engaged in processing behaviourally relevant stimuli with predictable spatio-temporal structure such as motion and speech. PMID:26623650

Trait-based diet selection: prey behaviour and morphology predict vulnerability to predation in reef fish communities.

PubMed

Green, Stephanie J; Côté, Isabelle M

2014-11-01

Understanding how predators select their prey can provide important insights into community structure and dynamics. However, the suite of prey species available to a predator is often spatially and temporally variable. As a result, species-specific selectivity data are of limited use for predicting novel predator-prey interactions because they are assemblage specific. We present a method for predicting diet selection that is applicable across prey assemblages, based on identifying general morphological and behavioural traits of prey that confer vulnerability to predation independent of species identity. We apply this trait-based approach to examining prey selection by Indo-Pacific lionfish (Pterois volitans and Pterois miles), invasive predators that prey upon species-rich reef fish communities and are rapidly spreading across the western Atlantic. We first generate hypotheses about morphological and behavioural traits recurring across fish species that could facilitate or deter predation by lionfish. Constructing generalized linear mixed-effects models that account for relatedness among prey taxa, we test whether these traits predict patterns of diet selection by lionfish within two independent data sets collected at different spatial scales: (i) in situ visual observations of prey consumption and availability for individual lionfish and (ii) comparisons of prey abundance in lionfish stomach contents to availability on invaded reefs at large. Both analyses reveal that a number of traits predicted to affect vulnerability to predation, including body size, body shape, position in the water column and aggregation behaviour, are important determinants of diet selection by lionfish. Small, shallow-bodied, solitary fishes found resting on or just above reefs are the most vulnerable. Fishes that exhibit parasite cleaning behaviour experience a significantly lower risk of predation than non-cleaning fishes, and fishes that are nocturnally active are at significantly greater risk. Together, vulnerable traits heighten the risk of predation by a factor of nearly 200. Our study reveals that a trait-based approach yields insights into predator-prey interactions that are robust across prey assemblages. Importantly, in situ observations of selection yield similar results to broadscale comparisons of prey use and availability, which are more typically gathered for predator species. A trait-based approach could therefore be of use across predator species and ecosystems to predict the outcomes of changing predator-prey interactions on community dynamics. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Investigation of magnetization dynamics in 2D Ni80Fe20 diatomic nanodot arrays

NASA Astrophysics Data System (ADS)

De, Anulekha; Mondal, Sucheta; Banerjee, Chandrima; Chaurasiya, Avinash K.; Mandal, Ruma; Otani, Yoshichika; Mitra, Rajib K.; Barman, Anjan

2017-09-01

Magnetization dynamics in Ni80Fe20 (Py) diatomic nanodots (nanodots of the same thickness but with large and small diameters that are closely placed to each other so as to act as a diatomic basis structure) embedded in 2D arrays have been investigated by the Brillouin light scattering technique. A distinct variation of resonant mode characteristics for different in-plane bias magnetic field applied along two different orientations of the lattice has been observed. Micromagnetic simulations reproduced the observed dynamical behaviour and revealed the variation of spatial distribution of collective modes of constituent single nanodots with different diameter and a diatomic unit forming the large array to understand the evolution of the magnetization dynamics from a single dot to the large array via a diatomic unit. The changes in mode frequency, spatial profiles of the modes, and appearance of new modes in a diatomic unit and its array from that of the constituent single dots indicate the strong magnetostatic interaction among the dots within the diatomic unit. Also, the occurrence of the new interacting mode at different frequencies for different orientations of the bias field indicates the change in the nature of interaction among the dots within the diatomic unit with bias magnetic field. The mode profiles also show distinct behaviour for smooth and rough-edged dots. This work motivates the study of magnonic band structure formation of such a dipolarly coupled nanodot array containing a complex double-dot unit cell.

Remote sensing as a tool to analyse lizards behaviour

NASA Astrophysics Data System (ADS)

Dos Santos, Remi; Teodoro, Ana C.; Carretero, Miguel; Sillero, Neftalí

2016-10-01

Although the spatial context is expected to be a major influence in the interactions among organisms and their environment, it is commonly ignored in ecological studies. This study is part of an investigation on home ranges and their influence in the escape behaviour of Iberian lizards. Fieldwork was conducted inside a 400 m2 mesocosm, using three acclimatized adult male individuals. In order to perform analyses at this local scale, tools with high spatial accuracy are needed. A total of 3016 GPS points were recorded and processed into a Digital Elevation Model (DEM), with a pixel resolution of 2 cm. Then, 1156 aerial photos were taken and processed to create an orthophoto. A refuge map, containing possible locations for retreats was generated with supervised image classification algorithms, obtaining four classes (refuges, vegetation, bare soil and organic soil). Furthermore, 50 data-loggers were randomly placed, recording evenly through the area temperature and humidity every 15'. After a month of recording, all environmental variables were interpolated using Kriging. The study area presented an irregular elevation. The humidity varied according to the topography and the temperature presented a West-East pattern. Both variables are of paramount importance for lizard activity and performance. In a predation risk scenario, a lizard located in a temperature close to its thermal optimum will be able to escape more efficiently. Integration of such ecologically relevant elements in a spatial context exemplifies how remote sensing tools can contribute to improve inference in behavioural ecology.

More than A to B: Understanding and managing visitor spatial behaviour in urban forests using public participation GIS.

PubMed

Korpilo, Silviya; Virtanen, Tarmo; Saukkonen, Tiina; Lehvävirta, Susanna

2018-02-01

Planning and management needs up-to-date, easily-obtainable and accurate information on the spatial and social aspects of visitor behaviour in order to balance human use and impacts, and protection of natural resources in public parks. We used a web-based public participation GIS (PPGIS) approach to gather citizen data on visitor behaviour in Helsinki's Central Park in order to aid collaborative spatial decision-making. The study combined smartphone GPS tracking, route drawing and a questionnaire to examine differences between user groups in their use of formal trails, off-trail behaviour and the motivations that affect it. In our sample (n = 233), different activity types were associated with distinctive spatial patterns and potential extent of impacts. The density mapping and statistical analyses indicated three types of behaviour: predominantly on or close to formal trails (runners and cyclists), spatially concentrated off-trail behaviour confined to a few informal paths (mountain bikers), and dispersed off-trail use pattern (walkers and dog walkers). Across all user groups, off-trail behaviour was mainly motivated by positive attraction towards the environment such as scenic view, exploration, and viewing flora and fauna. Study findings lead to several management recommendations that were presented to city officials. These include reducing dispersion and the spatial extent of trampling impacts by encouraging use of a limited number of well-established informal paths away from sensitive vegetation and protected habitats. Copyright © 2017 Elsevier Ltd. All rights reserved.

A data-model integration approach toward improved understanding on wetland functions and hydrological benefits at the catchment scale

NASA Astrophysics Data System (ADS)

Yeo, I. Y.; Lang, M.; Lee, S.; Huang, C.; Jin, H.; McCarty, G.; Sadeghi, A.

2017-12-01

The wetland ecosystem plays crucial roles in improving hydrological function and ecological integrity for the downstream water and the surrounding landscape. However, changing behaviours and functioning of wetland ecosystems are poorly understood and extremely difficult to characterize. Improved understanding on hydrological behaviours of wetlands, considering their interaction with surrounding landscapes and impacts on downstream waters, is an essential first step toward closing the knowledge gap. We present an integrated wetland-catchment modelling study that capitalizes on recently developed inundation maps and other geospatial data. The aim of the data-model integration is to improve spatial prediction of wetland inundation and evaluate cumulative hydrological benefits at the catchment scale. In this paper, we highlight problems arising from data preparation, parameterization, and process representation in simulating wetlands within a distributed catchment model, and report the recent progress on mapping of wetland dynamics (i.e., inundation) using multiple remotely sensed data. We demonstrate the value of spatially explicit inundation information to develop site-specific wetland parameters and to evaluate model prediction at multi-spatial and temporal scales. This spatial data-model integrated framework is tested using Soil and Water Assessment Tool (SWAT) with improved wetland extension, and applied for an agricultural watershed in the Mid-Atlantic Coastal Plain, USA. This study illustrates necessity of spatially distributed information and a data integrated modelling approach to predict inundation of wetlands and hydrologic function at the local landscape scale, where monitoring and conservation decision making take place.

Influence of landscape and social interactions on transmission of disease in a social cervid.

PubMed

Vander Wal, Eric; Paquet, Paul C; Andrés, José A

2012-03-01

The mechanisms of pathogen transmission are often social behaviours. These occur at local scales and are affected by landscape-scale population structure. Host populations frequently exist in patchy and isolated environments that create a continuum of genetic and social familiarity. Such variability has an important multispatial effect on pathogen spread. We assessed elk dispersal (i.e. likelihood of interdeme pathogen transmission) through spatially explicit genetic analyses. At a landscape scale, the elk population was composed of one cluster within a southeast-to-northwest cline spanning three spatially discrete subpopulations of elk across two protected areas in Manitoba (Canada). Genetic data are consistent with spatial variability in apparent prevalence of bovine tuberculosis (TB) in elk. Given the existing population structure, between-subpopulation spread of disease because of elk dispersal is unlikely. Furthermore, to better understand the risk of spread and distribution of the TB, we used a combination of close-contact logging biotelemetry and genetic data, which highlights how social intercourse may affect pathogen transmission. Our results indicate that close-contact interaction rate and duration did not covary with genetic relatedness. Thus, direct elk-to-elk transmission of disease is unlikely to be constrained to related individuals. That social intercourse in elk is not limited to familial groups provides some evidence pathogen transmission may be density-dependent. We show that the combination of landscape-scale genetics, relatedness and local-scale social behaviours is a promising approach to understand and predict landscape-level pathogen transmission within our system and within all social ungulate systems affected by transmissible diseases. © 2012 Blackwell Publishing Ltd.

War and peace: social interactions in infections

PubMed Central

Leggett, Helen C.; Brown, Sam P.; Reece, Sarah E.

2014-01-01

One of the most striking facts about parasites and microbial pathogens that has emerged in the fields of social evolution and disease ecology in the past few decades is that these simple organisms have complex social lives, indulging in a variety of cooperative, communicative and coordinated behaviours. These organisms have provided elegant experimental tests of the importance of relatedness, kin discrimination, cooperation and competition, in driving the evolution of social strategies. Here, we briefly review the social behaviours of parasites and microbial pathogens, including their contributions to virulence, and outline how inclusive fitness theory has helped to explain their evolution. We then take a mechanistically inspired ‘bottom-up’ approach, discussing how key aspects of the ways in which parasites and pathogens exploit hosts, namely public goods, mobile elements, phenotypic plasticity, spatial structure and multi-species interactions, contribute to the emergent properties of virulence and transmission. We argue that unravelling the complexities of within-host ecology is interesting in its own right, and also needs to be better incorporated into theoretical evolution studies if social behaviours are to be understood and used to control the spread and severity of infectious diseases. PMID:24686936

Frugivory and Spatial Patterns of Seed Deposition by Carnivorous Mammals in Anthropogenic Landscapes: A Multi-Scale Approach

PubMed Central

López-Bao, José V.; González-Varo, Juan P.

2011-01-01

Background Knowledge about how frugivory and seed deposition are spatially distributed is valuable to understand the role of dispersers on the structure and dynamics of plant populations. This may be particularly important within anthropogenic areas, where either the patchy distribution of wild plants or the presence of cultivated fleshy-fruits may influence plant-disperser interactions. Methodology/Principal Findings We investigated frugivory and spatial patterns of seed deposition by carnivorous mammals in anthropogenic landscapes considering two spatial scales: ‘landscape’ (∼10 km2) and ‘habitat type’ (∼1–2 km2). We sampled carnivore faeces and plant abundance at three contrasting habitats (chestnut woods, mosaics and scrublands), each replicated within three different landscapes. Sixty-five percent of faeces collected (n = 1077) contained seeds, among which wild and cultivated seeds appeared in similar proportions (58% and 53%) despite that cultivated fruiting plants were much less abundant. Seed deposition was spatially structured among both spatial scales being different between fruit types. Whereas the most important source of spatial variation in deposition of wild seeds was the landscape scale, it was the habitat scale for cultivated seeds. At the habitat scale, seeds of wild species were mostly deposited within mosaics while seeds of cultivated species were within chestnut woods and scrublands. Spatial concordance between seed deposition and plant abundance was found only for wild species. Conclusions/Significance Spatial patterns of seed deposition by carnivores differed between fruit types and seemed to be modulated by the fleshy-fruited plant assemblages and the behaviour of dispersers. Our results suggest that a strong preference for cultivated fruits by carnivores may influence their spatial foraging behaviour and lower their dispersal services to wild species. However, the high amount of seeds removed within and between habitats suggests that carnivores must play an important role – often overlooked – as ‘restorers’ and ‘habitat shapers’ in anthropogenic areas. PMID:21297861

How cognitive heuristics can explain social interactions in spatial movement.

PubMed

Seitz, Michael J; Bode, Nikolai W F; Köster, Gerta

2016-08-01

The movement of pedestrian crowds is a paradigmatic example of collective motion. The precise nature of individual-level behaviours underlying crowd movements has been subject to a lively debate. Here, we propose that pedestrians follow simple heuristics rooted in cognitive psychology, such as 'stop if another step would lead to a collision' or 'follow the person in front'. In other words, our paradigm explicitly models individual-level behaviour as a series of discrete decisions. We show that our cognitive heuristics produce realistic emergent crowd phenomena, such as lane formation and queuing behaviour. Based on our results, we suggest that pedestrians follow different cognitive heuristics that are selected depending on the context. This differs from the widely used approach of capturing changes in behaviour via model parameters and leads to testable hypotheses on changes in crowd behaviour for different motivation levels. For example, we expect that rushed individuals more often evade to the side and thus display distinct emergent queue formations in front of a bottleneck. Our heuristics can be ranked according to the cognitive effort that is required to follow them. Therefore, our model establishes a direct link between behavioural responses and cognitive effort and thus facilitates a novel perspective on collective behaviour. © 2016 The Author(s).

How cognitive heuristics can explain social interactions in spatial movement

PubMed Central

Köster, Gerta

2016-01-01

The movement of pedestrian crowds is a paradigmatic example of collective motion. The precise nature of individual-level behaviours underlying crowd movements has been subject to a lively debate. Here, we propose that pedestrians follow simple heuristics rooted in cognitive psychology, such as ‘stop if another step would lead to a collision’ or ‘follow the person in front’. In other words, our paradigm explicitly models individual-level behaviour as a series of discrete decisions. We show that our cognitive heuristics produce realistic emergent crowd phenomena, such as lane formation and queuing behaviour. Based on our results, we suggest that pedestrians follow different cognitive heuristics that are selected depending on the context. This differs from the widely used approach of capturing changes in behaviour via model parameters and leads to testable hypotheses on changes in crowd behaviour for different motivation levels. For example, we expect that rushed individuals more often evade to the side and thus display distinct emergent queue formations in front of a bottleneck. Our heuristics can be ranked according to the cognitive effort that is required to follow them. Therefore, our model establishes a direct link between behavioural responses and cognitive effort and thus facilitates a novel perspective on collective behaviour. PMID:27581483

Applications of step-selection functions in ecology and conservation.

PubMed

Thurfjell, Henrik; Ciuti, Simone; Boyce, Mark S

2014-01-01

Recent progress in positioning technology facilitates the collection of massive amounts of sequential spatial data on animals. This has led to new opportunities and challenges when investigating animal movement behaviour and habitat selection. Tools like Step Selection Functions (SSFs) are relatively new powerful models for studying resource selection by animals moving through the landscape. SSFs compare environmental attributes of observed steps (the linear segment between two consecutive observations of position) with alternative random steps taken from the same starting point. SSFs have been used to study habitat selection, human-wildlife interactions, movement corridors, and dispersal behaviours in animals. SSFs also have the potential to depict resource selection at multiple spatial and temporal scales. There are several aspects of SSFs where consensus has not yet been reached such as how to analyse the data, when to consider habitat covariates along linear paths between observations rather than at their endpoints, how many random steps should be considered to measure availability, and how to account for individual variation. In this review we aim to address all these issues, as well as to highlight weak features of this modelling approach that should be developed by further research. Finally, we suggest that SSFs could be integrated with state-space models to classify behavioural states when estimating SSFs.

Repeated mild traumatic brain injury produces neuroinflammation, anxiety-like behaviour and impaired spatial memory in mice.

PubMed

Broussard, John I; Acion, Laura; De Jesús-Cortés, Héctor; Yin, Terry; Britt, Jeremiah K; Salas, Ramiro; Costa-Mattioli, Mauro; Robertson, Claudia; Pieper, Andrew A; Arciniegas, David B; Jorge, Ricardo

2018-01-01

Repeated traumatic brain injuries (rmTBI) are frequently associated with debilitating neuropsychiatric conditions such as cognitive impairment, mood disorders, and post-traumatic stress disorder. We tested the hypothesis that repeated mild traumatic brain injury impairs spatial memory and enhances anxiety-like behaviour. We used a between groups design using single (smTBI) or repeated (rmTBI) controlled cranial closed skull impacts to mice, compared to a control group. We assessed the effects of smTBI and rmTBI using measures of motor performance (Rotarod Test [RT]), anxiety-like behaviour (Elevated Plus Maze [EPM] and Open Field [OF] tests), and spatial memory (Morris Water Maze [MWM]) within 12 days of the final injury. In separate groups of mice, astrocytosis and microglial activation were assessed 24 hours after the final injury using GFAP and IBA-1 immunohistochemistry. RmTBI impaired spatial memory in the MWM and increased anxiety-like behaviour in the EPM and OFT. In addition, rmTBI elevated GFAP and IBA-1 immunohistochemistry throughout the mouse brain. RmTBI produced astrocytosis and microglial activation, and elicited impaired spatial memory and anxiety-like behaviour. rmTBI produces acute cognitive and anxiety-like disturbances associated with inflammatory changes in brain regions involved in spatial memory and anxiety.

Attentional enhancement of spatial resolution: linking behavioural and neurophysiological evidence

PubMed Central

Anton-Erxleben, Katharina; Carrasco, Marisa

2014-01-01

Attention allows us to select relevant sensory information for preferential processing. Behaviourally, it improves performance in various visual tasks. One prominent effect of attention is the modulation of performance in tasks that involve the visual system’s spatial resolution. Physiologically, attention modulates neuronal responses and alters the profile and position of receptive fields near the attended location. Here, we develop a hypothesis linking the behavioural and electrophysiological evidence. The proposed framework seeks to explain how these receptive field changes enhance the visual system’s effective spatial resolution and how the same mechanisms may also underlie attentional effects on the representation of spatial information. PMID:23422910

The development of spatial behaviour and the hippocampal neural representation of space

PubMed Central

Wills, Thomas J.; Muessig, Laurenz; Cacucci, Francesca

2014-01-01

The role of the hippocampal formation in spatial cognition is thought to be supported by distinct classes of neurons whose firing is tuned to an organism's position and orientation in space. In this article, we review recent research focused on how and when this neural representation of space emerges during development: each class of spatially tuned neurons appears at a different age, and matures at a different rate, but all the main spatial responses tested so far are present by three weeks of age in the rat. We also summarize the development of spatial behaviour in the rat, describing how active exploration of space emerges during the third week of life, the first evidence of learning in formal tests of hippocampus-dependent spatial cognition is observed in the fourth week, whereas fully adult-like spatial cognitive abilities require another few weeks to be achieved. We argue that the development of spatially tuned neurons needs to be considered within the context of the development of spatial behaviour in order to achieve an integrated understanding of the emergence of hippocampal function and spatial cognition. PMID:24366148

Temporally and spatially partitioned behaviours of spinner dolphins: implications for resilience to human disturbance

PubMed Central

Johnston, David W.; Christiansen, Fredrik

2017-01-01

Selective forces shape the evolution of wildlife behavioural strategies and influence the spatial and temporal partitioning of behavioural activities to maximize individual fitness. Globally, wildlife is increasingly exposed to human activities which may affect their behavioural activities. The ability of wildlife to compensate for the effects of human activities may have implications for their resilience to disturbance. Resilience theory suggests that behavioural systems which are constrained in their repertoires are less resilient to disturbance than flexible systems. Using behavioural time-series data, we show that spinner dolphins (Stenella longirostris) spatially and temporally partition their behavioural activities on a daily basis. Specifically, spinner dolphins were never observed foraging during daytime, where resting was the predominant activity. Travelling and socializing probabilities were higher in early mornings and late afternoons when dolphins were returning from or preparing for nocturnal feeding trips, respectively. The constrained nature of spinner dolphin behaviours suggests they are less resilient to human disturbance than other cetaceans. These dolphins experience the highest exposure rates to human activities ever reported for any cetaceans. Over the last 30 years human activities have increased significantly in Hawaii, but the spinner dolphins still inhabit these bays. Recent abundance estimates (2011 and 2012) however, are lower than all previous estimates (1979–1981, 1989–1992 and 2003), indicating a possible long-term impact. Quantification of the spatial and temporal partitioning of wildlife behavioural schedules provides critical insight for conservation measures that aim to mitigate the effects of human disturbance. PMID:28280561

Temporally and spatially partitioned behaviours of spinner dolphins: implications for resilience to human disturbance.

PubMed

Tyne, Julian A; Johnston, David W; Christiansen, Fredrik; Bejder, Lars

2017-01-01

Selective forces shape the evolution of wildlife behavioural strategies and influence the spatial and temporal partitioning of behavioural activities to maximize individual fitness. Globally, wildlife is increasingly exposed to human activities which may affect their behavioural activities. The ability of wildlife to compensate for the effects of human activities may have implications for their resilience to disturbance. Resilience theory suggests that behavioural systems which are constrained in their repertoires are less resilient to disturbance than flexible systems. Using behavioural time-series data, we show that spinner dolphins ( Stenella longirostris ) spatially and temporally partition their behavioural activities on a daily basis. Specifically, spinner dolphins were never observed foraging during daytime, where resting was the predominant activity. Travelling and socializing probabilities were higher in early mornings and late afternoons when dolphins were returning from or preparing for nocturnal feeding trips, respectively. The constrained nature of spinner dolphin behaviours suggests they are less resilient to human disturbance than other cetaceans. These dolphins experience the highest exposure rates to human activities ever reported for any cetaceans. Over the last 30 years human activities have increased significantly in Hawaii, but the spinner dolphins still inhabit these bays. Recent abundance estimates (2011 and 2012) however, are lower than all previous estimates (1979-1981, 1989-1992 and 2003), indicating a possible long-term impact. Quantification of the spatial and temporal partitioning of wildlife behavioural schedules provides critical insight for conservation measures that aim to mitigate the effects of human disturbance.

Dorsolateral prefrontal lesions do not impair tests of scene learning and decision-making that require frontal–temporal interaction

PubMed Central

Baxter, Mark G; Gaffan, David; Kyriazis, Diana A; Mitchell, Anna S

2008-01-01

Theories of dorsolateral prefrontal cortex (DLPFC) involvement in cognitive function variously emphasize its involvement in rule implementation, cognitive control, or working and/or spatial memory. These theories predict broad effects of DLPFC lesions on tests of visual learning and memory. We evaluated the effects of DLPFC lesions (including both banks of the principal sulcus) in rhesus monkeys on tests of scene learning and strategy implementation that are severely impaired following crossed unilateral lesions of frontal cortex and inferotemporal cortex. Dorsolateral lesions had no effect on learning of new scene problems postoperatively, or on the implementation of preoperatively acquired strategies. They were also without effect on the ability to adjust choice behaviour in response to a change in reinforcer value, a capacity that requires interaction between the amygdala and frontal lobe. These intact abilities following DLPFC damage support specialization of function within the prefrontal cortex, and suggest that many aspects of memory and strategic and goal-directed behaviour can survive ablation of this structure. PMID:18702721

Comparison of automated home-cage monitoring systems: emphasis on feeding behaviour, activity and spatial learning following pharmacological interventions.

PubMed

Robinson, Lianne; Riedel, Gernot

2014-08-30

Different automated systems have been developed to facilitate long-term and continuous assessment of behaviours including locomotor activity, feeding behaviour and circadian activity. This study assessed the effectiveness of three different observation systems as methods for determining strain and pharmacological induced differences in locomotor activity, feeding behaviour and spatial learning. The effect of the CB1 antagonist AM251 on feeding behaviour was determined in the PhenoMaster and PhenoTyper. Next, effects of cholinergic (scopolamine) and glutamatergic (Phenylcyclidine, PCP) receptor antagonism and dopaminergic agonism (apomorphine) on activity were assessed in the PhenoTyper and IntelliCage. Finally, the IntelliCage was utilised to determine differences in activity and spatial learning of C57BL/6 and DBA/2 mouse strains following pharmacological intervention. AM251 induced a suppression of food intake, feeding behaviour and a reduction in body weight in both the PhenoTyper and PhenoMaster. Apomorphine reduced activity in both the PhenoTyper and IntelliCage. Whereas, decreased activity was evident with PCP in the PhenoTyper, but not IntelliCage and Scopolamine induced a trend towards elevated levels of activity in the IntelliCage but not PhenoTyper. Strain differences in activity and spatial learning were also evident, with increased corner visits and drug induced impairments only observed with C57BL/6 mice. The automated home cage observation systems determined similar drug and strain effects on behaviour to those observed using traditional methods. All three observation systems reported drug-induced changes in behaviour however, they differ in their application of spatial learning tasks and utilisation of single versus group housed recordings. Copyright © 2014 Elsevier B.V. All rights reserved.

Host and parasite life history interplay to yield divergent population genetic structures in two ectoparasites living on the same bat species.

PubMed

van Schaik, J; Dekeukeleire, D; Kerth, G

2015-05-01

Host-parasite interactions are ubiquitous in nature. However, how parasite population genetic structure is shaped by the interaction between host and parasite life history remains understudied. Studies comparing multiple parasites infecting a single host can be used to investigate how different parasite life history traits interplay with host behaviour and life history. In this study, we used 10 newly developed microsatellite loci to investigate the genetic structure of a parasitic bat fly (Basilia nana). Its host, the Bechstein's bat (Myotis bechsteinii), has a social system and roosting behaviour that restrict opportunities for parasite transmission. We compared fly genetic structure to that of the host and another parasite, the wing-mite, Spinturnix bechsteini. We found little spatial or temporal genetic structure in B. nana, suggesting a large, stable population with frequent genetic exchange between fly populations from different bat colonies. This contrasts sharply with the genetic structure of the wing-mite, which is highly substructured between the same bat colonies as well as temporally unstable. Our results suggest that although host and parasite life history interact to yield similar transmission patterns in both parasite species, the level of gene flow and eventual spatiotemporal genetic stability is differentially affected. This can be explained by the differences in generation time and winter survival between the flies and wing-mites. Our study thus exemplifies that the population genetic structure of parasites on a single host can vary strongly as a result of how their individual life history characteristics interact with host behaviour and life history traits. © 2015 John Wiley & Sons Ltd.

Similarities and differences between the brain networks underlying allocentric and egocentric spatial learning in rat revealed by cytochrome oxidase histochemistry.

PubMed

Rubio, S; Begega, A; Méndez, M; Méndez-López, M; Arias, J L

2012-10-25

The involvement of different brain regions in place- and response-learning was examined using a water cross-maze. Rats were trained to find the goal from the initial arm by turning left at the choice point (egocentric strategy) or by using environmental cues (allocentric strategy). Although different strategies were required, the same maze and learning conditions were used. Using cytochrome oxidase histochemistry as a marker of cellular activity, the function of the 13 diverse cortical and subcortical regions was assessed in rats performing these two tasks. Our results show that allocentric learning depends on the recruitment of a large functional network, which includes the hippocampal CA3, dentate gyrus, medial mammillary nucleus and supramammillary nucleus. Along with the striatum, these last three structures are also related to egocentric spatial learning. The present study provides evidence for the contribution of these regions to spatial navigation and supports a possible functional interaction between the two memory systems, as their structural convergence may facilitate functional cooperation in the behaviours guided by more than one strategy. In summary, it can be argued that spatial learning is based on dynamic functional systems in which the interaction of brain regions is modulated by task requirements. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Two fluid anisotropic dark energy models in a scale invariant theory

NASA Astrophysics Data System (ADS)

Tripathy, S. K.; Mishra, B.; Sahoo, P. K.

2017-09-01

Some anisotropic Bianchi V dark energy models are investigated in a scale invariant theory of gravity. We consider two non-interacting fluids such as dark energy and a bulk viscous fluid. Dark energy pressure is considered to be anisotropic in different spatial directions. A dynamically evolving pressure anisotropy is obtained from the models. The models favour phantom behaviour. It is observed that, in presence of dark energy, bulk viscosity has no appreciable effect on the cosmic dynamics.

Roles of Oestrogen Receptors α and β in Behavioural Neuroendocrinology: Beyond Yin/Yang

PubMed Central

Rissman, E. F.

2009-01-01

Oestrogen receptor β (ERβ) was discovered more than 10 years ago. It is widely distributed in the brain. In some areas, such as the entorhinal cortex, it is present as the only ER, whereas in other regions, such as the bed nucleus of the stria terminalis and preoptic area, it can be found co-expressed with ERα, often within the same neurones. These ERs share ligands, and there are several complex relationships between the two receptors. Initially, the relationship between them was labelled as ‘yin/yang’, meaning that the actions of each complemented those of the other, but now, years later, other relationships have been described. Based on evidence from neuroendocrine and behavioural studies, three types of interactions between the two oestrogen receptors are described in this review. The first relationship is antagonistic; this is evident from studies on the role of oestrogen in spatial learning. When oestradiol is given in a high, chronic dose, spatial learning is impaired. This action of oestradiol requires ERα, and when ERβ is not functional, lower doses of oestradiol have this negative effect on behaviour. The second relationship between the two receptors is one that is synergistic, and this is illustrated in the combined effects of the two receptors on the production of the neuropeptide oxytocin and its receptor. The third relationship is sequential; separate actions of the two receptors are postulated in activation and organisation of sexually dimorphic reproductive behaviours. Future studies on all of these topics will inform us about how ER selective ligands might affect oestrogen functions at the organismal level. PMID:18601711

The walking behaviour of pedestrian social groups and its impact on crowd dynamics.

PubMed

Moussaïd, Mehdi; Perozo, Niriaska; Garnier, Simon; Helbing, Dirk; Theraulaz, Guy

2010-04-07

Human crowd motion is mainly driven by self-organized processes based on local interactions among pedestrians. While most studies of crowd behaviour consider only interactions among isolated individuals, it turns out that up to 70% of people in a crowd are actually moving in groups, such as friends, couples, or families walking together. These groups constitute medium-scale aggregated structures and their impact on crowd dynamics is still largely unknown. In this work, we analyze the motion of approximately 1500 pedestrian groups under natural condition, and show that social interactions among group members generate typical group walking patterns that influence crowd dynamics. At low density, group members tend to walk side by side, forming a line perpendicular to the walking direction. As the density increases, however, the linear walking formation is bent forward, turning it into a V-like pattern. These spatial patterns can be well described by a model based on social communication between group members. We show that the V-like walking pattern facilitates social interactions within the group, but reduces the flow because of its "non-aerodynamic" shape. Therefore, when crowd density increases, the group organization results from a trade-off between walking faster and facilitating social exchange. These insights demonstrate that crowd dynamics is not only determined by physical constraints induced by other pedestrians and the environment, but also significantly by communicative, social interactions among individuals.

Body size mediated coexistence of consumers competing for resources in space

USGS Publications Warehouse

Basset, A.; Angelis, D.L.

2007-01-01

Body size is a major phenotypic trait of individuals that commonly differentiates co-occurring species. We analyzed inter-specific competitive interactions between a large consumer and smaller competitors, whose energetics, selection and giving-up behaviour on identical resource patches scaled with individual body size. The aim was to investigate whether pure metabolic constraints on patch behaviour of vagile species can determine coexistence conditions consistent with existing theoretical and experimental evidence. We used an individual-based spatially explicit simulation model at a spatial scale defined by the home range of the large consumer, which was assumed to be parthenogenic and semelparous. Under exploitative conditions, competitive coexistence occurred in a range of body size ratios between 2 and 10. Asymmetrical competition and the mechanism underlying asymmetry, determined by the scaling of energetics and patch behaviour with consumer body size, were the proximate determinant of inter-specific coexistence. The small consumer exploited patches more efficiently, but searched for profitable patches less effectively than the larger competitor. Therefore, body-size related constraints induced niche partitioning, allowing competitive coexistence within a set of conditions where the large consumer maintained control over the small consumer and resource dynamics. The model summarises and extends the existing evidence of species coexistence on a limiting resource, and provides a mechanistic explanation for decoding the size-abundance distribution patterns commonly observed at guild and community levels. ?? Oikos.

Modelling the spatial behaviour of a tropical tuna purse seine fleet.

PubMed

Davies, Tim K; Mees, Chris C; Milner-Gulland, E J

2014-01-01

Industrial tuna fisheries operate in the Indian, Atlantic and Pacific Oceans, but concerns over sustainability and environmental impacts of these fisheries have resulted in increased scrutiny of how they are managed. An important but often overlooked factor in the success or failure of tuna fisheries management is the behaviour of fishers and fishing fleets. Uncertainty in how a fishing fleet will respond to management or other influences can be reduced by anticipating fleet behaviour, although to date there has been little research directed at understanding and anticipating the human dimension of tuna fisheries. The aim of this study was to address gaps in knowledge of the behaviour of tuna fleets, using the Indian Ocean tropical tuna purse seine fishery as a case study. We use statistical modelling to examine the factors that influence the spatial behaviour of the purse seine fleet at broad spatiotemporal scales. This analysis reveals very high consistency between years in the use of seasonal fishing grounds by the fleet, as well as a forcing influence of biophysical ocean conditions on the distribution of fishing effort. These findings suggest strong inertia in the spatial behaviour of the fleet, which has important implications for predicting the response of the fleet to natural events or management measures (e.g., spatial closures).

Personality and problem-solving in common mynas (Acridotheres tristis).

PubMed

Lermite, Françoise; Peneaux, Chloé; Griffin, Andrea S

2017-01-01

Animals show consistent individual differences in behaviour across time and/or contexts. Recently, it has been suggested that proactive personality types might also exhibit fast cognitive styles. The speed with which individuals sample environmental cues is one way in which correlations between personality and cognition might arise. Here, we measured a collection of behavioural traits (competitiveness, neophobia, neophilia, task-directed motivation and exploration) in common mynas (Acridotheres tristis) and measured their relationship with problem solving. We predicted that fast solving mynas would interact with (i.e. sample) the problem solving task at higher rates, but also be more competitive, less neophobic, more neophilic, and more exploratory. Mynas that were faster to solve a novel foraging problem were no more competitive around food and no more inclined to take risks. Unexpectedly, these fast-solving mynas had higher rates of interactions with the task, but also displayed lower levels of exploration. It is possible that a negative relation between problem solving and spatial exploration arose as a consequence of how inter-individual variation in exploration was quantified. We discuss the need for greater consensus on how to measure exploratory behaviour before we can advance our understanding of relationships between cognition and personality more effectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Position-based dynamic of a particle system: a configurable algorithm to describe complex behaviour of continuum material starting from swarm robotics

NASA Astrophysics Data System (ADS)

dell'Erba, Ramiro

2018-04-01

In a previous work, we considered a two-dimensional lattice of particles and calculated its time evolution by using an interaction law based on the spatial position of the particles themselves. The model reproduced the behaviour of deformable bodies both according to the standard Cauchy model and second gradient theory; this success led us to use this method in more complex cases. This work is intended as the natural evolution of the previous one in which we shall consider both energy aspects, coherence with the principle of Saint Venant and we start to manage a more general tool that can be adapted to different physical phenomena, supporting complex effects like lateral contraction, anisotropy or elastoplasticity.

Curcumin Enhances Neurogenesis and Cognition in Aged Rats: Implications for Transcriptional Interactions Related to Growth and Synaptic Plasticity

PubMed Central

Mitchell, E. Siobhan; Xiu, Jin; Tiwari, Jyoti K.; Hu, Yinghe; Cao, Xiaohua; Zhao, Zheng

2012-01-01

Background Curcumin has been demonstrated to have many neuroprotective properties, including improvement of cognition in humans and neurogenesis in animals, yet the mechanism of such effects remains unclear. Methodology We assessed behavioural performance and hippocampal cell proliferation in aged rats after 6- and 12-week curcumin-fortified diets. Curcumin enhanced non-spatial and spatial memory, as well as dentate gyrate cell proliferation as compared to control diet rats. We also investigated underlying mechanistic pathways that might link curcumin treatment to increased cognition and neurogenesis via exon array analysis of cortical and hippocampal mRNA transcription. The results revealed a transcriptional network interaction of genes involved in neurotransmission, neuronal development, signal transduction, and metabolism in response to the curcumin treatment. Conclusions The results suggest a neurogenesis- and cognition-enhancing potential of prolonged curcumin treatment in aged rats, which may be due to its diverse effects on genes related to growth and plasticity. PMID:22359574

LAPSUS: soil erosion - landscape evolution model

NASA Astrophysics Data System (ADS)

van Gorp, Wouter; Temme, Arnaud; Schoorl, Jeroen

2015-04-01

LAPSUS is a soil erosion - landscape evolution model which is capable of simulating landscape evolution of a gridded DEM by using multiple water, mass movement and human driven processes on multiple temporal and spatial scales. It is able to deal with a variety of human landscape interventions such as landuse management and tillage and it can model their interactions with natural processes. The complex spatially explicit feedbacks the model simulates demonstrate the importance of spatial interaction of human activity and erosion deposition patterns. In addition LAPSUS can model shallow landsliding, slope collapse, creep, solifluction, biological and frost weathering, fluvial behaviour. Furthermore, an algorithm to deal with natural depressions has been added and event-based modelling with an improved infiltration description and dust deposition has been pursued. LAPSUS has been used for case studies in many parts of the world and is continuously developing and expanding. it is now available for third-party and educational use. It has a comprehensive user interface and it is accompanied by a manual and exercises. The LAPSUS model is highly suitable to quantify and understand catchment-scale erosion processes. More information and a download link is available on www.lapsusmodel.nl.

In-silico experiments of zebrafish behaviour: modeling swimming in three dimensions

NASA Astrophysics Data System (ADS)

Mwaffo, Violet; Butail, Sachit; Porfiri, Maurizio

2017-01-01

Zebrafish is fast becoming a species of choice in biomedical research for the investigation of functional and dysfunctional processes coupled with their genetic and pharmacological modulation. As with mammals, experimentation with zebrafish constitutes a complicated ethical issue that calls for the exploration of alternative testing methods to reduce the number of subjects, refine experimental designs, and replace live animals. Inspired by the demonstrated advantages of computational studies in other life science domains, we establish an authentic data-driven modelling framework to simulate zebrafish swimming in three dimensions. The model encapsulates burst-and-coast swimming style, speed modulation, and wall interaction, laying the foundations for in-silico experiments of zebrafish behaviour. Through computational studies, we demonstrate the ability of the model to replicate common ethological observables such as speed and spatial preference, and anticipate experimental observations on the correlation between tank dimensions on zebrafish behaviour. Reaching to other experimental paradigms, our framework is expected to contribute to a reduction in animal use and suffering.

Challenges and solutions for studying collective animal behaviour in the wild.

PubMed

Hughey, Lacey F; Hein, Andrew M; Strandburg-Peshkin, Ariana; Jensen, Frants H

2018-05-19

Mobile animal groups provide some of the most compelling examples of self-organization in the natural world. While field observations of songbird flocks wheeling in the sky or anchovy schools fleeing from predators have inspired considerable interest in the mechanics of collective motion, the challenge of simultaneously monitoring multiple animals in the field has historically limited our capacity to study collective behaviour of wild animal groups with precision. However, recent technological advancements now present exciting opportunities to overcome many of these limitations. Here we review existing methods used to collect data on the movements and interactions of multiple animals in a natural setting. We then survey emerging technologies that are poised to revolutionize the study of collective animal behaviour by extending the spatial and temporal scales of inquiry, increasing data volume and quality, and expediting the post-processing of raw data.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Author(s).

A 'dynamic' landscape of fear: prey responses to spatiotemporal variations in predation risk across the lunar cycle.

PubMed

Palmer, M S; Fieberg, J; Swanson, A; Kosmala, M; Packer, C

2017-11-01

Ambiguous empirical support for 'landscapes of fear' in natural systems may stem from failure to consider dynamic temporal changes in predation risk. The lunar cycle dramatically alters night-time visibility, with low luminosity increasing hunting success of African lions. We used camera-trap data from Serengeti National Park to examine nocturnal anti-predator behaviours of four herbivore species. Interactions between predictable fluctuations in night-time luminosity and the underlying risk-resource landscape shaped herbivore distribution, herding propensity and the incidence of 'relaxed' behaviours. Buffalo responded least to temporal risk cues and minimised risk primarily through spatial redistribution. Gazelle and zebra made decisions based on current light levels and lunar phase, and wildebeest responded to lunar phase alone. These three species avoided areas where likelihood of encountering lions was high and changed their behaviours in risky areas to minimise predation threat. These patterns support the hypothesis that fear landscapes vary heterogeneously in both space and time. © 2017 John Wiley & Sons Ltd/CNRS.

In-silico experiments of zebrafish behaviour: modeling swimming in three dimensions

PubMed Central

Mwaffo, Violet; Butail, Sachit; Porfiri, Maurizio

2017-01-01

Zebrafish is fast becoming a species of choice in biomedical research for the investigation of functional and dysfunctional processes coupled with their genetic and pharmacological modulation. As with mammals, experimentation with zebrafish constitutes a complicated ethical issue that calls for the exploration of alternative testing methods to reduce the number of subjects, refine experimental designs, and replace live animals. Inspired by the demonstrated advantages of computational studies in other life science domains, we establish an authentic data-driven modelling framework to simulate zebrafish swimming in three dimensions. The model encapsulates burst-and-coast swimming style, speed modulation, and wall interaction, laying the foundations for in-silico experiments of zebrafish behaviour. Through computational studies, we demonstrate the ability of the model to replicate common ethological observables such as speed and spatial preference, and anticipate experimental observations on the correlation between tank dimensions on zebrafish behaviour. Reaching to other experimental paradigms, our framework is expected to contribute to a reduction in animal use and suffering. PMID:28071731

Spatial distribution and cluster analysis of risky sexual behaviours and STDs reported by Chinese adults in Guangzhou, China: a representative population-based study

PubMed Central

Chen, Wen; Zhou, Fangjing; Hall, Brian J; Wang, Yu; Latkin, Carl; Ling, Li; Tucker, Joseph D

2016-01-01

Objectives To assess associations between residences location, risky sexual behaviours and sexually transmitted diseases (STDs) among adults living in Guangzhou, China. Methods Data were obtained from 751 Chinese adults aged 18–59 years in Guangzhou, China, using stratified random sampling by using spatial epidemiological methods. Face-to-face household interviews were conducted to collect self-report data on risky sexual behaviours and diagnosed STDs. Kulldorff’s spatial scan statistic was implemented to identify and detect spatial distribution and clusters of risky sexual behaviours and STDs. The presence and location of statistically significant clusters were mapped in the study areas using ArcGIS software. Results The prevalence of self-reported risky sexual behaviours was between 5.1% and 50.0%. The self-reported lifetime prevalence of diagnosed STDs was 7.06%. Anal intercourse clustered in an area located along the border within the rural–urban continuum (p=0.001). High rate clusters for alcohol or other drugs using before sex (p=0.008) and migrants who lived in Guangzhou <1 year (p=0.007) overlapped this cluster. Excess cases for unprotected sex (p=0.031) overlapped the cluster for college students (p<0.001). Five of nine (55.6%) students who had sexual experience during the last 12 months located in the cluster of unprotected sex. Conclusions Short-term migrants and college students reported greater risky sexual behaviours. Programmes to increase safer sex within these communities to reduce the risk of STDs are warranted in Guangzhou. Spatial analysis identified geographical clusters of risky sexual behaviours, which is critical for optimising surveillance and targeting control measures for these locations in the future. PMID:26843400

Task relevance modulates the behavioural and neural effects of sensory predictions

PubMed Central

Friston, Karl J.; Nobre, Anna C.

2017-01-01

The brain is thought to generate internal predictions to optimize behaviour. However, it is unclear whether predictions signalling is an automatic brain function or depends on task demands. Here, we manipulated the spatial/temporal predictability of visual targets, and the relevance of spatial/temporal information provided by auditory cues. We used magnetoencephalography (MEG) to measure participants’ brain activity during task performance. Task relevance modulated the influence of predictions on behaviour: spatial/temporal predictability improved spatial/temporal discrimination accuracy, but not vice versa. To explain these effects, we used behavioural responses to estimate subjective predictions under an ideal-observer model. Model-based time-series of predictions and prediction errors (PEs) were associated with dissociable neural responses: predictions correlated with cue-induced beta-band activity in auditory regions and alpha-band activity in visual regions, while stimulus-bound PEs correlated with gamma-band activity in posterior regions. Crucially, task relevance modulated these spectral correlates, suggesting that current goals influence PE and prediction signalling. PMID:29206225

The automated analysis of clustering behaviour of piglets from thermal images in response to immune challenge by vaccination.

PubMed

Cook, N J; Bench, C J; Liu, T; Chabot, B; Schaefer, A L

2018-01-01

An automated method of estimating the spatial distribution of piglets within a pen was used to assess huddling behaviour under normal conditions and during a febrile response to vaccination. The automated method was compared with a manual assessment of clustering activity. Huddling behaviour was partly related to environmental conditions and clock time such that more huddling occurred during the night and at lower ambient air temperatures. There were no positive relationships between maximum pig temperatures and environmental conditions, suggesting that the narrow range of air temperatures in this study was not a significant factor for pig temperature. Spatial distribution affected radiated pig temperature measurements by IR thermography. Higher temperatures were recorded in groups of animals displaying huddling behaviour. Huddling behaviour was affected by febrile responses to vaccination with increased huddling occurring 3 to 8 h post-vaccination. The automated method of assessing spatial distribution from an IR image successfully identified periods of huddling associated with a febrile response, and to changing environmental temperatures. Infrared imaging could be used to quantify temperature and behaviour from the same images.

Auditory observation of stepping actions can cue both spatial and temporal components of gait in Parkinson׳s disease patients.

PubMed

Young, William R; Rodger, Matthew W M; Craig, Cathy M

2014-05-01

A common behavioural symptom of Parkinson׳s disease (PD) is reduced step length (SL). Whilst sensory cueing strategies can be effective in increasing SL and reducing gait variability, current cueing strategies conveying spatial or temporal information are generally confined to the use of either visual or auditory cue modalities, respectively. We describe a novel cueing strategy using ecologically-valid 'action-related' sounds (footsteps on gravel) that convey both spatial and temporal parameters of a specific action within a single cue. The current study used a real-time imitation task to examine whether PD affects the ability to re-enact changes in spatial characteristics of stepping actions, based solely on auditory information. In a second experimental session, these procedures were repeated using synthesized sounds derived from recordings of the kinetic interactions between the foot and walking surface. A third experimental session examined whether adaptations observed when participants walked to action-sounds were preserved when participants imagined either real recorded or synthesized sounds. Whilst healthy control participants were able to re-enact significant changes in SL in all cue conditions, these adaptations, in conjunction with reduced variability of SL were only observed in the PD group when walking to, or imagining the recorded sounds. The findings show that while recordings of stepping sounds convey action information to allow PD patients to re-enact and imagine spatial characteristics of gait, synthesis of sounds purely from gait kinetics is insufficient to evoke similar changes in behaviour, perhaps indicating that PD patients have a higher threshold to cue sensorimotor resonant responses. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Dispersal kernels and their drivers captured with a hydrodynamic model and spatial indices: A case study on anchovy ( Engraulis encrasicolus) early life stages in the Bay of Biscay

NASA Astrophysics Data System (ADS)

Huret, M.; Petitgas, P.; Woillez, M.

2010-10-01

Dispersal of fish early life stages explains part of the recruitment success, through interannual variability in spawning, transport and survival. Dispersal results from a complex interaction between physical and biological processes acting at different temporal and spatial scales, and at the individual or population level. In this paper we quantify the response of anchovy egg and larval dispersal in the Bay of Biscay to the following sources of variability: vertical larval behaviour, drift duration, adult spawning location and timing, and spatio-temporal variability in the hydrodynamics. We use simulations of Lagrangian trajectories in a 3-dimensional hydrodynamic model, as well as spatial indices describing different properties of the dispersal kernel: the mean transport (distance, direction), its variance, occupation of space by particles and their aggregation. We show that larval drift duration has a major impact on the dispersion at scales of ˜100 km, but that vertical behaviour becomes dominant reducing dispersion at scales of ˜1-10 km. Spawning location plays a major role in explaining connectivity patterns, in conjunction with spawning temporal variability. Interannual variability in the circulation dominates over seasonal variability. However, seasonal patterns become predominant for coastal spawning locations, revealing a recurrent shift in the direction of dispersal during the anchovy spawning season.

Quantum chaos and breaking of all anti-unitary symmetries in Rydberg excitons.

PubMed

Aßmann, Marc; Thewes, Johannes; Fröhlich, Dietmar; Bayer, Manfred

2016-07-01

Symmetries are the underlying principles of fundamental interactions in nature. Chaos in a quantum system may emerge from breaking these symmetries. Compared to vacuum, crystals are attractive for studying quantum chaos, as they not only break spatial isotropy, but also lead to novel quasiparticles with modified interactions. Here we study yellow Rydberg excitons in cuprous oxide which couple strongly to the vacuum light field and interact significantly with crystal phonons, leading to inversion symmetry breaking. In a magnetic field, time-reversal symmetry is also broken and the exciton states show a complex splitting pattern, resulting in quadratic level repulsion for small splittings. In contrast to atomic chaotic systems in a magnetic field, which show only a linear level repulsion, this is a signature of a system where all anti-unitary symmetries are broken simultaneously. This behaviour can otherwise be found only for the electro-weak interaction or engineered billiards.

Searching for effective forces in laboratory insect swarms

NASA Astrophysics Data System (ADS)

Puckett, James G.; Kelley, Douglas H.; Ouellette, Nicholas T.

2014-04-01

Collective animal behaviour is often modeled by systems of agents that interact via effective social forces, including short-range repulsion and long-range attraction. We search for evidence of such effective forces by studying laboratory swarms of the flying midge Chironomus riparius. Using multi-camera stereoimaging and particle-tracking techniques, we record three-dimensional trajectories for all the individuals in the swarm. Acceleration measurements show a clear short-range repulsion, which we confirm by considering the spatial statistics of the midges, but no conclusive long-range interactions. Measurements of the mean free path of the insects also suggest that individuals are on average very weakly coupled, but that they are also tightly bound to the swarm itself. Our results therefore suggest that some attractive interaction maintains cohesion of the swarms, but that this interaction is not as simple as an attraction to nearest neighbours.

Social influence on associative learning: double dissociation in high-functioning autism, early-stage behavioural variant frontotemporal dementia and Alzheimer's disease.

PubMed

Kéri, Szabolcs

2014-05-01

Most of our learning activity takes place in a social context. I examined how social interactions influence associative learning in neurodegenerative diseases and atypical neurodevelopmental conditions primarily characterised by social cognitive and memory dysfunctions. Participants were individuals with high-functioning autism (HFA, n = 18), early-stage behavioural variant frontotemporal dementia (bvFTD, n = 16) and Alzheimer's disease (AD, n = 20). The leading symptoms in HFA and bvFTD were social and behavioural dysfunctions, whereas AD was characterised by memory deficits. Participants received three versions of a paired associates learning task. In the game with boxes test, objects were hidden in six candy boxes placed in different locations on the computer screen. In the game with faces, each box was labelled by a photo of a person. In the real-life version of the game, participants played with real persons. Individuals with HFA and bvFTD performed well in the computer games, but failed on the task including real persons. In contrast, in patients with early-stage AD, social interactions boosted paired associates learning up to the level of healthy control volunteers. Worse performance in the real life game was associated with less successful recognition of complex emotions and mental states in the Reading the Mind in the Eyes Test. Spatial span did not affect the results. When social cognition is impaired, but memory systems are less compromised (HFA and bvFTD), real-life interactions disrupt associative learning; when disease process impairs memory systems but social cognition is relatively intact (early-stage AD), social interactions have a beneficial effect on learning and memory. Copyright © 2014 Elsevier Ltd. All rights reserved.

The effects of aerobic exercise on depression-like, anxiety-like, and cognition-like behaviours over the healthy adult lifespan of C57BL/6 mice.

PubMed

Morgan, Julie A; Singhal, Gaurav; Corrigan, Frances; Jaehne, Emily J; Jawahar, Magdalene C; Baune, Bernhard T

2018-01-30

Preclinical studies have demonstrated exercise improves various types of behaviours such as anxiety-like, depression-like, and cognition-like behaviours. However, these findings were largely conducted in studies utilising short-term exercise protocols, and the effects of lifetime exercise on these behaviours remain unknown. This study investigates the behavioural effects of lifetime exercise in normal healthy ageing C57BL/6 mice over the adult lifespan. 12 week-old C57BL/6 mice were randomly assigned to voluntary wheel running or non-exercise (control) groups. Exercise commenced at aged 3 months and behaviours were assessed in young adult (Y), early middle age (M), and old (O) mice (n=11-17/group). The open field and elevated zero maze examined anxiety-like behaviours, depression-like behaviours were quantified with the forced swim test, and the Y maze and Barnes maze investigated cognition-like behaviours. The effects of lifetime exercise were not simply an extension of the effects of chronic exercise on anxiety-like, depression-like, and cognition-like behaviours. Exercise tended to reduce overt anxiety-like behaviours with ageing, and improved recognition memory and spatial learning in M mice as was expected. However, exercise also increased anxiety behaviours including greater freezing behaviour that extended spatial learning latencies in Y female mice in particular, while reduced distances travelled contributed to longer spatial memory and cognitive flexibility latencies in Y and O mice. Lifetime exercise may increase neurogenesis-associated anxiety. This could be an evolutionary conserved adaptation that nevertheless has adverse impacts on cognition-like function, with particularly pronounced effects in Y female mice with intact sex hormones. These issues require careful investigation in future rodent studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Ecological dynamics of continuous and categorical decision-making: the regatta start in sailing.

PubMed

Araújo, Duarte; Davids, Keith; Diniz, Ana; Rocha, Luis; Santos, João Coelho; Dias, Gonçalo; Fernandes, Orlando

2015-01-01

Ecological dynamics of decision-making in the sport of sailing exemplifies emergent, conditionally coupled, co-adaptive behaviours. In this study, observation of the coupling dynamics of paired boats during competitive sailing showed that decision-making can be modelled as a self-sustained, co-adapting system of informationally coupled oscillators (boats). Bytracing the spatial-temporal displacements of the boats, time series analyses (autocorrelations, periodograms and running correlations) revealed that trajectories of match racing boats are coupled more than 88% of the time during a pre-start race, via continuous, competing co-adaptions between boats. Results showed that both the continuously selected trajectories of the sailors (12 years of age) and their categorical starting point locations were examples of emergent decisions. In this dynamical conception of decision-making behaviours, strategic positioning (categorical) and continuous displacement of a boat over the course in match-race sailing emerged as a function of interacting task, personal and environmental constraints. Results suggest how key interacting constraints could be manipulated in practice to enhance sailors' perceptual attunement to them in competition.

Body size affects the strength of social interactions and spatial organization of a schooling fish (Pseudomugil signifer)

NASA Astrophysics Data System (ADS)

Romenskyy, Maksym; Herbert-Read, James E.; Ward, Ashley J. W.; Sumpter, David J. T.

2017-04-01

While a rich variety of self-propelled particle models propose to explain the collective motion of fish and other animals, rigorous statistical comparison between models and data remains a challenge. Plausible models should be flexible enough to capture changes in the collective behaviour of animal groups at their different developmental stages and group sizes. Here, we analyse the statistical properties of schooling fish (Pseudomugil signifer) through a combination of experiments and simulations. We make novel use of a Boltzmann inversion method, usually applied in molecular dynamics, to identify the effective potential of the mean force of fish interactions. Specifically, we show that larger fish have a larger repulsion zone, but stronger attraction, resulting in greater alignment in their collective motion. We model the collective dynamics of schools using a self-propelled particle model, modified to include varying particle speed and a local repulsion rule. We demonstrate that the statistical properties of the fish schools are reproduced by our model, thereby capturing a number of features of the behaviour and development of schooling fish.

Agent-based modelling of consumer energy choices

NASA Astrophysics Data System (ADS)

Rai, Varun; Henry, Adam Douglas

2016-06-01

Strategies to mitigate global climate change should be grounded in a rigorous understanding of energy systems, particularly the factors that drive energy demand. Agent-based modelling (ABM) is a powerful tool for representing the complexities of energy demand, such as social interactions and spatial constraints. Unlike other approaches for modelling energy demand, ABM is not limited to studying perfectly rational agents or to abstracting micro details into system-level equations. Instead, ABM provides the ability to represent behaviours of energy consumers -- such as individual households -- using a range of theories, and to examine how the interaction of heterogeneous agents at the micro-level produces macro outcomes of importance to the global climate, such as the adoption of low-carbon behaviours and technologies over space and time. We provide an overview of ABM work in the area of consumer energy choices, with a focus on identifying specific ways in which ABM can improve understanding of both fundamental scientific and applied aspects of the demand side of energy to aid the design of better policies and programmes. Future research needs for improving the practice of ABM to better understand energy demand are also discussed.

Astronomical bounds on a cosmological model allowing a general interaction in the dark sector

NASA Astrophysics Data System (ADS)

Pan, Supriya; Mukherjee, Ankan; Banerjee, Narayan

2018-06-01

Non-gravitational interaction between two barotropic dark fluids, namely the pressureless dust and the dark energy in a spatially flat Friedmann-Lemaître-Robertson-Walker model, has been discussed. It is shown that for the interactions that are linear in terms the energy densities of the dark components and their first order derivatives, the net energy density is governed by a second-order differential equation with constant coefficients. Taking a generalized interaction, which includes a number of already known interactions as special cases, the dynamics of the universe is described for three types of the dark energy equation of state, namely that of interacting quintessence, interacting vacuum energy density, and interacting phantom. The models have been constrained using the standard cosmological probes, Supernovae Type Ia data from joint light curve analysis and the observational Hubble parameter data. Two geometric tests, the cosmographic studies, and the Om diagnostic have been invoked so as to ascertain the behaviour of the present model vis-a-vis the Λ-cold dark matter model. We further discussed the interacting scenarios taking into account the thermodynamic considerations.

A comparison of the seasonal movements of tiger sharks and green turtles provides insight into their predator-prey relationship.

PubMed

Fitzpatrick, Richard; Thums, Michele; Bell, Ian; Meekan, Mark G; Stevens, John D; Barnett, Adam

2012-01-01

During the reproductive season, sea turtles use a restricted area in the vicinity of their nesting beaches, making them vulnerable to predation. At Raine Island (Australia), the highest density green turtle Chelonia mydas rookery in the world, tiger sharks Galeocerdo cuvier have been observed to feed on green turtles, and it has been suggested that they may specialise on such air-breathing prey. However there is little information with which to examine this hypothesis. We compared the spatial and temporal components of movement behaviour of these two potentially interacting species in order to provide insight into the predator-prey relationship. Specifically, we tested the hypothesis that tiger shark movements are more concentrated at Raine Island during the green turtle nesting season than outside the turtle nesting season when turtles are not concentrated at Raine Island. Turtles showed area-restricted search behaviour around Raine Island for ∼3-4 months during the nesting period (November-February). This was followed by direct movement (transit) to putative foraging grounds mostly in the Torres Straight where they switched to area-restricted search mode again, and remained resident for the remainder of the deployment (53-304 days). In contrast, tiger sharks displayed high spatial and temporal variation in movement behaviour which was not closely linked to the movement behaviour of green turtles or recognised turtle foraging grounds. On average, tiger sharks were concentrated around Raine Island throughout the year. While information on diet is required to determine whether tiger sharks are turtle specialists our results support the hypothesis that they target this predictable and plentiful prey during turtle nesting season, but they might not focus on this less predictable food source outside the nesting season.

A Comparison of the Seasonal Movements of Tiger Sharks and Green Turtles Provides Insight into Their Predator-Prey Relationship

PubMed Central

Fitzpatrick, Richard; Thums, Michele; Bell, Ian; Meekan, Mark G.; Stevens, John D.; Barnett, Adam

2012-01-01

During the reproductive season, sea turtles use a restricted area in the vicinity of their nesting beaches, making them vulnerable to predation. At Raine Island (Australia), the highest density green turtle Chelonia mydas rookery in the world, tiger sharks Galeocerdo cuvier have been observed to feed on green turtles, and it has been suggested that they may specialise on such air-breathing prey. However there is little information with which to examine this hypothesis. We compared the spatial and temporal components of movement behaviour of these two potentially interacting species in order to provide insight into the predator-prey relationship. Specifically, we tested the hypothesis that tiger shark movements are more concentrated at Raine Island during the green turtle nesting season than outside the turtle nesting season when turtles are not concentrated at Raine Island. Turtles showed area-restricted search behaviour around Raine Island for ∼3–4 months during the nesting period (November–February). This was followed by direct movement (transit) to putative foraging grounds mostly in the Torres Straight where they switched to area-restricted search mode again, and remained resident for the remainder of the deployment (53–304 days). In contrast, tiger sharks displayed high spatial and temporal variation in movement behaviour which was not closely linked to the movement behaviour of green turtles or recognised turtle foraging grounds. On average, tiger sharks were concentrated around Raine Island throughout the year. While information on diet is required to determine whether tiger sharks are turtle specialists our results support the hypothesis that they target this predictable and plentiful prey during turtle nesting season, but they might not focus on this less predictable food source outside the nesting season. PMID:23284819

Migration in a segmented labour market.

PubMed

Gordon, I

1995-01-01

"Current research in migration is moving on from neo-classical and behavioural perspectives to a more structural approach relating to wider processes, issues of power and the particular role of employers. Within this programme a key issue for investigation is the interaction between spatial mobility and the structuring of labour markets. This paper focuses on the significance of labour market segmentation--in terms both of job stability and gender--for migration, both theoretically and through an empirical analysis of data from the UK Labour Force Survey on sponsored and unsponsored moves." excerpt

Predator encounters have spatially extensive impacts on parental behaviour in a breeding bird community

PubMed Central

Moks, Kadri; Thomson, Robert L.; Calhim, Sara; Järvistö, Pauliina E.; Schuett, Wiebke; Velmala, William; Laaksonen, Toni

2016-01-01

Predation risk has negative indirect effects on prey fitness, partly mediated through changes in behaviour. Evidence that individuals gather social information from other members of the population suggests that events in a community may impact the behaviour of distant individuals. However, spatially wide-ranging impacts on individual behaviour caused by a predator encounter elsewhere in a community have not been documented before. We investigated the effect of a predator encounter (hawk model presented at a focal nest) on the parental behaviour of pied flycatchers (Ficedula hypoleuca), both at the focal nest and at nearby nests different distances from the predator encounter. We show that nest visitation of both focal pairs and nearby pairs were affected, up to 3 h and 1 h, respectively. Parents also appeared to compensate initial disrupted feeding by later increasing nest visitation rates. This is the first evidence showing that the behaviour of nearby pairs was affected away from an immediate source of risk. Our results indicate that the impacts of short-term predator encounters may immediately extend spatially to the broader community, affecting the behaviour of distant individuals. Information about predators is probably quickly spread by cues such as intra- and heterospecific alarm calls, in communities of different taxa. PMID:27030411

Genetic composition of social groups influences male aggressive behaviour and fitness in natural genotypes of Drosophila melanogaster.

PubMed

Saltz, Julia B

2013-11-22

Indirect genetic effects (IGEs) describe how an individual's behaviour-which is influenced by his or her genotype-can affect the behaviours of interacting individuals. IGE research has focused on dyads. However, insights from social networks research, and other studies of group behaviour, suggest that dyadic interactions are affected by the behaviour of other individuals in the group. To extend IGE inferences to groups of three or more, IGEs must be considered from a group perspective. Here, I introduce the 'focal interaction' approach to study IGEs in groups. I illustrate the utility of this approach by studying aggression among natural genotypes of Drosophila melanogaster. I chose two natural genotypes as 'focal interactants': the behavioural interaction between them was the 'focal interaction'. One male from each focal interactant genotype was present in every group, and I varied the genotype of the third male-the 'treatment male'. Genetic variation in the treatment male's aggressive behaviour influenced the focal interaction, demonstrating that IGEs in groups are not a straightforward extension of IGEs measured in dyads. Further, the focal interaction influenced male mating success, illustrating the role of IGEs in behavioural evolution. These results represent the first manipulative evidence for IGEs at the group level.

Peripubertal viral-like challenge and social isolation mediate overlapping but distinct effects on behaviour and brain interferon regulatory factor 7 expression in the adult Wistar rat.

PubMed

Lukasz, Bartlomiej; O'Sullivan, Niamh C; Loscher, Jennifer S; Pickering, Mark; Regan, Ciaran M; Murphy, Keith J

2013-01-01

A range of adverse, early life environmental influences such as viral infection and social deprivation are thought to increase risk of psychiatric illness later in life. Here, we used peripheral administration of the viral infection mimic polyriboinosinic-polyribocytidylic acid (polyI:C) to compare the consequences of peripubertal infection and isolation rearing. Isolation rearing induced deficits in sensorimotor gating and recognition memory while no changes in social interaction or spatial learning were observed. PolyI:C injection during the peripubertal period markedly increased expression of interferon-stimulated genes (Ifit2, Prkr, Mx2 and Irf7) in the hippocampal dentate gyrus demonstrating that peripheral administration of the viral mimic in the adolescent animal does have direct effects in the brain. Peripubertal infection mimicry induced a similar but later emerging behavioural deficit in prepulse inhibition implying the existence of a peripubertal window of opportunity for viral-mediated cytokine increases to impact brain development and function. PolyI:C treatment also impaired novel object recognition but did not alter spatial reference memory or social interaction. Combining the polyI:C challenge with social isolation did not exacerbate the behavioural deficits seen with isolation rearing alone. Using Irf7 as a marker, peripubertal viral infection mimicry, isolation rearing and a combination of both were all seen to produce a long-lasting molecular imprint on the interferon-associated signalling pathway in the principal neuron population of the hippocampal dentate gyrus. The data suggest that the sensitivity of brain structure and function to disruption by viral infection extends into the peripubertal period. Moreover, augmented interferon signalling in hippocampus may represent a common molecular imprint of environmental insults associated with neuropsychiatric illnesses like schizophrenia. Copyright © 2012 Elsevier Inc. All rights reserved.

Interactive robots in experimental biology.

PubMed

Krause, Jens; Winfield, Alan F T; Deneubourg, Jean-Louis

2011-07-01

Interactive robots have the potential to revolutionise the study of social behaviour because they provide several methodological advances. In interactions with live animals, the behaviour of robots can be standardised, morphology and behaviour can be decoupled (so that different morphologies and behavioural strategies can be combined), behaviour can be manipulated in complex interaction sequences and models of behaviour can be embodied by the robot and thereby be tested. Furthermore, robots can be used as demonstrators in experiments on social learning. As we discuss here, the opportunities that robots create for new experimental approaches have far-reaching consequences for research in fields such as mate choice, cooperation, social learning, personality studies and collective behaviour. Copyright © 2011 Elsevier Ltd. All rights reserved.

Laboratory incubation experiments assessing the factor interactions affecting urine-derived nitrous oxide emissions from spatially and temporally variable upland pastures

NASA Astrophysics Data System (ADS)

Charteris, Alice; Loick, Nadine; Marsden, Karina; Chadwick, Dave; Whelan, Mick; Rao Ravella, Sreenivas; Mead, Andrew; Cardenas, Laura

2017-04-01

Urine patches deposited to soils by grazing animals represent hot-spots of nitrous oxide (N2O) emissions (Hargreaves et al., 2015), a powerful greenhouse gas (GHG) and precursor of ozone depletion in the stratosphere. Urine N2O emissions are produced via nitrification of ureolysis-derived ammonium (NH4+) and/or subsequent nitrite (NO2-) and nitrate (NO3-) denitrification (Kool et al., 2006). The dominant process and the N2O fluxes generated depend on interactions between urine characteristics (e.g. nitrogen [N] concentration and volume), soil characteristics (e.g. carbon [C] availability and pH) and preceding and prevailing environmental conditions (e.g. soil moisture and temperature; Bergstermann et al., 2011; Butterbach-Bahl et al., 2013; Dijkstra et al., 2013). The spatial and temporal variability of these interactions in grazing systems is potentially large and greatly increases the uncertainty associated with N2O emission estimates from such systems. In particular, the contribution of extensively managed upland agroecosystems, which occupy ca. 5.5 million hectares in the UK and provide the bulk of land for sheep farming (Pollott & Stone, 2004), to UK GHG emissions is poorly defined. Improving understanding of the interactions between the wide range of factors affecting urine-derived N2O production and emission from pasture soils and considering this in the context of the spatial and temporal variability of the grazing environment could therefore be extremely valuable in improving the accuracy of N2O emission estimates from such systems. The factorial laboratory incubation experiments presented have been designed to assess the interactive effects of factors such as urine N concentration, volume and soil moisture affecting soil N2O (and nitric oxide [NO], nitrogen gas [N2] and carbon dioxide [CO2]) production and emissions (García-Marco et al., 2014) using the state-of-the-art Denitrification Incubation System (DENIS). This work forms part of a wider project aimed at improving understanding of the spatial and temporal interactions between sheep grazing behaviour, forage selection, urine composition and edaphic factors to increase the accuracy of direct N2O emission estimates from extensive upland systems. Two upland pastures at Henfaes Research Centre (Bangor University) are being used for field measurements and the laboratory incubation experiments have been designed to reflect these systems. This includes using soils sampled by non-hierarchical clustering to accurately represent the sites, re-packed in layers (to field-measured bulk density) and selecting factors and levels based on data from field experiments. The relationships between N2O fluxes and the N2O:N2 mole fraction resulting from factor interactions will be used in a pasture-scale model of upland N2O emissions which integrates the spatial and temporal variability of sheep diet and behaviour, urine deposition characteristics, topography and soil physico-chemical measurements. The approach will generate more accurate N2O emission estimates from extensive grazing systems. The improved process-level understanding gained will aid the development of appropriate mitigation strategies. Bergstermann (2011) SBB 43, 240-250. Butterbach-Bahl (2013) Phil. T. R. Soc. B 368, DOI:10.1098/rstb.2013.0122. Dijkstra (2013) Animal 7, 292-302. García-Marco (2014) EJSS 65, 573-583. Hargreaves (2015) Environ. & Nat. Res. Res. 5, DOI:10.5539/enrr.v5n4p1. Kool (2006) SBB 38, 1757-1763. Pollott & Stone (2004) The Breeding Structure of the British Sheep Industry 2003, Defra, UK.

Processing spatial layout by perception and sensorimotor interaction.

PubMed

Bridgeman, Bruce; Hoover, Merrit

2008-06-01

Everyone has the feeling that perception is usually accurate - we apprehend the layout of the world without significant error, and therefore we can interact with it effectively. Several lines of experimentation, however, show that perceived layout is seldom accurate enough to account for the success of visually guided behaviour. A visual world that has more texture on one side, for example, induces a shift of the body's straight ahead to that side and a mislocalization of a small target to the opposite side. Motor interaction with the target remains accurate, however, as measured by a jab with the finger. Slopes of hills are overestimated, even while matching the slopes of the same hills with the forearm is more accurate. The discrepancy shrinks as the estimated range is reduced, until the two estimates are hardly discrepant for a segment of a slope within arm's reach. From an evolutionary standpoint, the function of perception is not to provide an accurate physical layout of the world, but to inform the planning of future behaviour. Illusions - inaccuracies in perception - are perceived as such only when they can be verified by objective means, such as measuring the slope of a hill, the range of a landmark, or the location of a target. Normally such illusions are not checked and are accepted as reality without contradiction.

Assessing preschoolers interactive behaviour: A validation study of the "Coding System for Mother-Child Interaction".

PubMed

Baiao, R; Baptista, J; Carneiro, A; Pinto, R; Toscano, C; Fearon, P; Soares, I; Mesquita, A R

2018-07-01

The preschool years are a period of great developmental achievements, which impact critically on a child's interactive skills. Having valid and reliable measures to assess interactive behaviour at this stage is therefore crucial. The aim of this study was to describe the adaptation and validation of the child coding of the Coding System for Mother-Child Interactions and discuss its applications and implications in future research and practice. Two hundred twenty Portuguese preschoolers and their mothers were videotaped during a structured task. Child and mother interactive behaviours were coded based on the task. Maternal reports on the child's temperament and emotional and behaviour problems were also collected, along with family psychosocial information. Interrater agreement was confirmed. The use of child Cooperation, Enthusiasm, and Negativity as subscales was supported by their correlations across tasks. Moreover, these subscales were correlated with each other, which supports the use of a global child interactive behaviour score. Convergent validity with a measure of emotional and behavioural problems (Child Behaviour Checklist 1 ½-5) was established, as well as divergent validity with a measure of temperament (Children's Behaviour Questionnaire-Short Form). Regarding associations with family variables, child interactive behaviour was only associated with maternal behaviour. Findings suggest that this coding system is a valid and reliable measure for assessing child interactive behaviour in preschool age children. It therefore represents an important alternative to this area of research and practice, with reduced costs and with more flexible training requirements. Attention should be given in future research to expanding this work to clinical populations and different age groups. © 2018 John Wiley & Sons Ltd.

Fishing out collective memory of migratory schools

PubMed Central

De Luca, Giancarlo; Mariani, Patrizio; MacKenzie, Brian R.; Marsili, Matteo

2014-01-01

Animals form groups for many reasons, but there are costs and benefits associated with group formation. One of the benefits is collective memory. In groups on the move, social interactions play a crucial role in the cohesion and the ability to make consensus decisions. When migrating from spawning to feeding areas, fish schools need to retain a collective memory of the destination site over thousands of kilometres, and changes in group formation or individual preference can produce sudden changes in migration pathways. We propose a modelling framework, based on stochastic adaptive networks, that can reproduce this collective behaviour. We assume that three factors control group formation and school migration behaviour: the intensity of social interaction, the relative number of informed individuals and the strength of preference that informed individuals have for a particular migration area. We treat these factors independently and relate the individuals’ preferences to the experience and memory for certain migration sites. We demonstrate that removal of knowledgeable individuals or alteration of individual preference can produce rapid changes in group formation and collective behaviour. For example, intensive fishing targeting the migratory species and also their preferred prey can reduce both terms to a point at which migration to the destination sites is suddenly stopped. The conceptual approaches represented by our modelling framework may therefore be able to explain large-scale changes in fish migration and spatial distribution. PMID:24647905

Fishing out collective memory of migratory schools.

PubMed

De Luca, Giancarlo; Mariani, Patrizio; MacKenzie, Brian R; Marsili, Matteo

2014-06-06

Animals form groups for many reasons, but there are costs and benefits associated with group formation. One of the benefits is collective memory. In groups on the move, social interactions play a crucial role in the cohesion and the ability to make consensus decisions. When migrating from spawning to feeding areas, fish schools need to retain a collective memory of the destination site over thousands of kilometres, and changes in group formation or individual preference can produce sudden changes in migration pathways. We propose a modelling framework, based on stochastic adaptive networks, that can reproduce this collective behaviour. We assume that three factors control group formation and school migration behaviour: the intensity of social interaction, the relative number of informed individuals and the strength of preference that informed individuals have for a particular migration area. We treat these factors independently and relate the individuals' preferences to the experience and memory for certain migration sites. We demonstrate that removal of knowledgeable individuals or alteration of individual preference can produce rapid changes in group formation and collective behaviour. For example, intensive fishing targeting the migratory species and also their preferred prey can reduce both terms to a point at which migration to the destination sites is suddenly stopped. The conceptual approaches represented by our modelling framework may therefore be able to explain large-scale changes in fish migration and spatial distribution.

Elucidating the significance of spatial memory on movement decisions by African savannah elephants using state–space models

PubMed Central

Polansky, Leo; Kilian, Werner; Wittemyer, George

2015-01-01

Spatial memory facilitates resource acquisition where resources are patchy, but how it influences movement behaviour of wide-ranging species remains to be resolved. We examined African elephant spatial memory reflected in movement decisions regarding access to perennial waterholes. State–space models of movement data revealed a rapid, highly directional movement behaviour almost exclusively associated with visiting perennial water. Behavioural change point (BCP) analyses demonstrated that these goal-oriented movements were initiated on average 4.59 km, and up to 49.97 km, from the visited waterhole, with the closest waterhole accessed 90% of the time. Distances of decision points increased when switching to different waterholes, during the dry season, or for female groups relative to males, while selection of the closest waterhole decreased when switching. Overall, our analyses indicated detailed spatial knowledge over large scales, enabling elephants to minimize travel distance through highly directional movement when accessing water. We discuss the likely cognitive and socioecological mechanisms driving these spatially precise movements that are most consistent with our findings. By applying modern analytic techniques to high-resolution movement data, this study illustrates emerging approaches for studying how cognition structures animal movement behaviour in different ecological and social contexts. PMID:25808888

A spatial model for conflict incorporating within- and between-actor effects

NASA Astrophysics Data System (ADS)

Knipl, Diána; Davies, Toby; Baudains, Peter

2017-10-01

The application of ecological models to human conflict scenarios has given rise to a number of models which describe antagonistic relationships between adversaries. Recent work demonstrates that the spatial disaggregation of such models is not only well-motivated but also gives rise to interesting dynamic behaviour, particularly with respect to the spatial distribution of resources. One feature which is largely absent from previous models, however, is the ability of an adversary to coordinate activity across its various locations. Most immediately, this corresponds to the notion of 'support' - the reallocation of resources from one site to another according to need - which plays an important role in real-world conflict. In this paper, we generalise a spatially-disaggregated form of the classic Richardson model of conflict escalation by adding a cross-location interaction term for the within-adversary dynamics at each location. We explore the model analytically, giving conditions for the stability of the balanced equilibrium state. We then also carry out a number of numerical simulations which correspond to stylised real-world conflict scenarios. Potential further applications of the model, and its implications for policy, are then discussed.

Camera-related behaviours of female dental nurses and nursery school children during fluoride varnish application interactions in nursery school settings.

PubMed

Zhou, Yuefang; Forbes, Gillian M; Humphris, Gerry

2010-09-01

To investigate camera awareness of female dental nurses and nursery school children as the frequency of camera-related behaviours observed during fluoride varnish applications in a community based health programme. Fifty-one nurse-child interactions (three nurse pairs and 51 children) were video recorded when Childsmile nurses were applying fluoride varnish onto the teeth of children in nursery school settings. Using a pre-developed coding scheme, nurse and child verbal and nonverbal behaviours were coded for camera-related behaviours. On 15 of 51 interactions (29.4%), a total of 31 camera-related behaviours were observed for dental nurses (14 instances over nine interactions) and children (17 instances over six interactions). Camera-related behaviours occurred infrequently, occupied 0.3% of the total interaction time and displayed at all stages of the dental procedure, though tended to peak at initial stages. Certain camera-related behaviours of female dental nurses and nursery school children were observed in their interactions when introducing a dental health preventive intervention. Since the frequency of camera-related behaviours are so few they are of little consequence when video-recording adults and children undertaking dental procedures.

Latent interaction effects in the theory of planned behaviour applied to quitting smoking.

PubMed

Hukkelberg, Silje Sommer; Hagtvet, Knut A; Kovac, Velibor Bobo

2014-02-01

This study applies three latent interaction models in the theory of planned behaviour (TPB; Ajzen, 1988, Attitudes, personality, and behavior. Homewood, IL: Dorsey Press; Ajzen, 1991, Organ. Behav. Hum. Decis. Process., 50, 179) to quitting smoking: (1) attitude × perceived behavioural control on intention; (2) subjective norms (SN) × attitude on intention; and (3) perceived behavioural control × intention on quitting behaviour. The data derive from a longitudinal Internet survey of 939 smokers aged 15-74 over a period of 4 months. Latent interaction effects were estimated using the double-mean-centred unconstrained approach (Lin et al., 2010, Struct. Equ. Modeling, 17, 374) in LISREL. Attitude × SN and attitude × perceived behavioural control both showed a significant interaction effect on intention. No significant interaction effect was found for perceived behavioural control × intention on quitting. The latent interaction approach is a useful method for investigating specific conditions between TPB components in the context of quitting behaviour. Theoretical and practical implications of the results are discussed. © 2013 The British Psychological Society.

Fortune favours the brave: Movement responses shape demographic dynamics in strongly competing populations.

PubMed

Potts, Jonathan R; Petrovskii, Sergei V

2017-05-07

Animal movement is a key mechanism for shaping population dynamics. The effect of interactions between competing animals on a population's survival has been studied for many decades. However, interactions also affect an animal's subsequent movement decisions. Despite this, the indirect effect of these decisions on animal survival is much less well-understood. Here, we incorporate movement responses to foreign animals into a model of two competing populations, where inter-specific competition is greater than intra-specific competition. When movement is diffusive, the travelling wave moves from the stronger population to the weaker. However, by incorporating behaviourally induced directed movement towards the stronger population, the weaker one can slow the travelling wave down, even reversing its direction. Hence movement responses can switch the predictions of traditional mechanistic models. Furthermore, when environmental heterogeneity is combined with aggressive movement strategies, it is possible for spatially segregated co-existence to emerge. In this situation, the spatial patterns of the competing populations have the unusual feature that they are slightly out-of-phase with the environmental patterns. Finally, incorporating dynamic movement responses can also enable stable co-existence in a homogeneous environment, giving a new mechanism for spatially segregated co-existence. Copyright © 2017 Elsevier Ltd. All rights reserved.

Estimating resource acquisition and at-sea body condition of a marine predator

PubMed Central

Schick, Robert S; New, Leslie F; Thomas, Len; Costa, Daniel P; Hindell, Mark A; McMahon, Clive R; Robinson, Patrick W; Simmons, Samantha E; Thums, Michele; Harwood, John; Clark, James S

2013-01-01

Body condition plays a fundamental role in many ecological and evolutionary processes at a variety of scales and across a broad range of animal taxa. An understanding of how body condition changes at fine spatial and temporal scales as a result of interaction with the environment provides necessary information about how animals acquire resources. However, comparatively little is known about intra- and interindividual variation of condition in marine systems. Where condition has been studied, changes typically are recorded at relatively coarse time-scales. By quantifying how fine-scale interaction with the environment influences condition, we can broaden our understanding of how animals acquire resources and allocate them to body stores. Here we used a hierarchical Bayesian state-space model to estimate the body condition as measured by the size of an animal's lipid store in two closely related species of marine predator that occupy different hemispheres: northern elephant seals (Mirounga angustirostris) and southern elephant seals (Mirounga leonina). The observation model linked drift dives to lipid stores. The process model quantified daily changes in lipid stores as a function of the physiological condition of the seal (lipid:lean tissue ratio, departure lipid and departure mass), its foraging location, two measures of behaviour and environmental covariates. We found that physiological condition significantly impacted lipid gain at two time-scales – daily and at departure from the colony – that foraging location was significantly associated with lipid gain in both species of elephant seals and that long-term behavioural phase was associated with positive lipid gain in northern and southern elephant seals. In northern elephant seals, the occurrence of short-term behavioural states assumed to represent foraging were correlated with lipid gain. Lipid gain was a function of covariates in both species. Southern elephant seals performed fewer drift dives than northern elephant seals and gained lipids at a lower rate. We have demonstrated a new way to obtain time series of body condition estimates for a marine predator at fine spatial and temporal scales. This modelling approach accounts for uncertainty at many levels and has the potential to integrate physiological and movement ecology of top predators. The observation model we used was specific to elephant seals, but the process model can readily be applied to other species, providing an opportunity to understand how animals respond to their environment at a fine spatial scale. PMID:23869551

Non-homogeneous Behaviour of the Spatial Distribution of Macrospicules

NASA Astrophysics Data System (ADS)

Gyenge, N.; Bennett, S.; Erdélyi, R.

2015-03-01

In this paper the longitudinal and latitudinal spatial distribution of macrospicules is examined. We found a statistical relationship between the active longitude (determined by sunspot groups) and the longitudinal distribution of macrospicules. This distribution of macrospicules shows an inhomogeneity and non-axisymmetrical behaviour in the time interval between June 2010 and December 2012, covered by observations of the Solar Dynamic Observatory (SDO) satellite. The enhanced positions of the activity and its time variation have been calculated. The migration of the longitudinal distribution of macrospicules shows a similar behaviour to that of the sunspot groups.

[Affective behavioural responses by dogs to tactile human-dog interactions].

PubMed

Kuhne, Franziska; Hössler, Johanna C; Struwe, Rainer

2012-01-01

The communication of dogs is based on complex, subtle body postures and facial expressions. Some social interaction between dogs includes physical contact. Humans generally use both verbal and tactile signals to communicate with dogs. Hence, interaction between humans and dogs might lead to conflicts because the behavioural responses of dogs to human-dog interaction may be misinterpreted and wrongly assessed. The behavioural responses of dogs to tactile human-dog interactions and human gestures are the focus of this study. The participating dogs (n = 47) were privately owned pets.They were of varying breed and gender.The test consisted of nine randomised test sequences (e. g. petting the dog's head or chest). A test sequence was performed for a period of 30 seconds. The inter-trial interval was set at 60 seconds and the test-retest interval was set at 10 minutes. The frequency and duration of the dogs'behavioural responses were recorded using INTERACT. To examine the behavioural responses of the dogs, a two-way analysis of variance within the linear mixed models procedure of IBM SPSS Statistics 19 was conducted. A significant influence of the test-sequenc order on the dogs' behaviour could be analysed for appeasement gestures (F8,137 = 2.42; p = 0.018), redirected behaviour (F8,161 = 6.31; p = 0.012) and socio-positive behaviour (F8,148 = 6.28; p = 0.012). The behavioural responses of the dogs, which were considered as displacement activities (F8,109 = 2.5; p = 0.014) differed significantly among the test sequences. The response of the dogs, measured as gestures of appeasement, redirected behaviours, and displacement activities, was most obvious during petting around the head and near the paws.The results of this study conspicuously indicate that dogs respond to tactile human-dog interactions with gestures of appeasement and displacement activities. Redirected behaviours, socio-positive behaviours as well displacement activities are behavioural responses which dogs mainly show after a human-dog interaction.

Quality of both parents' cognitive guidance and quantity of early childhood education: Influences on pre-mathematical development.

PubMed

Sorariutta, Anne; Silvén, Maarit

2018-06-01

Only a handful of longitudinal studies have explored the effects of both parents in early parenthood on children's cognitive development, and no study has controlled for simultaneous early childhood education and care (ECEC) experiences. To examine the similarity of each parent's cognitive guidance and contribution to children's pre-mathematical outcomes across parent gender while controlling for amount of ECEC. A longitudinal study on 66 Finnish two-parent families and their children. Both parents' autonomy support and scaffolding behaviour were observed during play interactions with the child at 2;0. Children's numerical and spatial skills were tested at 3;0 and 4;0. Parental reports on amount of ECEC in months were collected at 2;0, 3;0, and 4;0. The two parenting constructs were conceptually similar across parent gender as demonstrated by fairly strong measurement equivalence. While mothers on average showed more scaffolding and equal amounts of autonomy support compared to fathers during play interaction, they displayed less variability in the former and more variability in the latter behaviour. The contribution of mothers' and fathers' cognitive guidance was more similar for children's numerical than spatial development. Both parents' education positively predicted autonomy support but not amount of ECEC exposure, which was positively related to numerical development. As expected, parents' education did not predict ECEC exposure, and child gender was not related to child outcomes. The findings are discussed in relation to measurement invariance and gender-neutral parenting in the context of early childhood. © 2018 The British Psychological Society.

The D1CT-7 mouse model of Tourette syndrome displays sensorimotor gating deficits in response to spatial confinement.

PubMed

Godar, Sean C; Mosher, Laura J; Strathman, Hunter J; Gochi, Andrea M; Jones, Cori M; Fowler, Stephen C; Bortolato, Marco

2016-07-01

The D1CT-7 mouse is one of the best known animal models of Tourette syndrome (TS), featuring spontaneous tic-like behaviours sensitive to standard TS therapies; these characteristics ensure a high face and predictive validity of this model, yet its construct validity remains elusive. To address this issue, we studied the responses of D1CT-7 mice to two critical components of TS pathophysiology: the exacerbation of tic-like behaviours in response to stress and the presence of sensorimotor gating deficits, which are thought to reflect the perceptual alterations causing the tics. D1CT-7 and wild-type (WT) littermates were subjected to a 20 min session of spatial confinement (SC) within an inescapable, 10 cm wide cylindrical enclosure. Changes in plasma corticosterone levels, tic-like behaviours and other spontaneous responses were measured. SC-exposed mice were also tested for the prepulse inhibition (PPI) of the startle response (a sensorimotor gating index) and other TS-related behaviours, including open-field locomotion, novel object exploration and social interaction and compared with non-confined counterparts. SC produced a marked increase in corticosterone concentrations in both D1CT-7 and WT mice. In D1CT-7, but not WT mice, SC exacerbated tic-like and digging behaviours, and triggered PPI deficits and aggressive responses. Conversely, SC did not modify locomotor activity or novel object exploration in D1CT-7 mice. Both tic-like behaviours and PPI impairments in SC-exposed D1CT-7 mice were inhibited by standard TS therapies and D1 dopamine receptor antagonism. These findings collectively support the translational and construct validity of D1CT-7 mice with respect to TS. This article is part of a themed section on Updating Neuropathology and Neuropharmacology of Monoaminergic Systems. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.13/issuetoc. © 2015 The British Pharmacological Society.

Astronomical and atmospheric impacts on deep-sea hydrothermal vent invertebrates

PubMed Central

Legendre, Pierre; Matabos, Marjolaine; Mihály, Steve; Lee, Raymond W.; Sarradin, Pierre-Marie; Arango, Claudia P.; Sarrazin, Jozée

2017-01-01

Ocean tides and winter surface storms are among the main factors driving the dynamics and spatial structure of marine coastal species, but the understanding of their impact on deep-sea and hydrothermal vent communities is still limited. Multidisciplinary deep-sea observatories offer an essential tool to study behavioural rhythms and interactions between hydrothermal community dynamics and environmental fluctuations. Here, we investigated whether species associated with a Ridgeia piscesae tubeworm vent assemblage respond to local ocean dynamics. By tracking variations in vent macrofaunal abundance at different temporal scales, we provide the first evidence that tides and winter surface storms influence the distribution patterns of mobile and non-symbiotic hydrothermal species (i.e. pycnogonids Sericosura sp. and Polynoidae polychaetes) at more than 2 km depth. Local ocean dynamics affected the mixing between hydrothermal fluid inputs and surrounding seawater, modifying the environmental conditions in vent habitats. We suggest that hydrothermal species respond to these habitat modifications by adjusting their behaviour to ensure optimal living conditions. This behaviour may reflect a specific adaptation of vent species to their highly variable habitat. PMID:28381618

Light triggers habitat choice of eyeless subterranean but not of eyed surface amphipods.

PubMed

Fišer, Žiga; Novak, Luka; Luštrik, Roman; Fišer, Cene

2016-02-01

Boundaries of species distributions are the result of colonization-extinction processes. Survival on the boundary depends on how well individuals discriminate optimal from suboptimal habitat patches. Such behaviour is called habitat choice and was only rarely applied to macroecology, although it links species ecological niche and species distribution. Surface and subterranean aquatic species are spatially strongly segregated, even in the absence of physical barriers. We explored whether a behavioural response to light functions as a habitat choice mechanism that could explain species turnover between surface and subterranean aquatic ecosystems. In a controlled laboratory experiment, we studied the behavioural response to light of ten pairs of surface and subterranean amphipods that permanently co-occur in springs. Surface species showed a weak photophobic, photoneutral, and in one case, photophilic response, whereas all subterranean species showed a strong photophobic response. Eyeless subterranean but not eyed surface amphipods appear to orient themselves with light cues. On a local scale, this difference possibly diminishes harmful interactions between the co-occurring amphipods, whereas on a regional scale, photophobia could explain limited dispersal and a high degree of endemism observed among subterranean species.

Estimating spatial accessibility to facilities on the regional scale: an extended commuting-based interaction potential model

PubMed Central

2011-01-01

Background There is growing interest in the study of the relationships between individual health-related behaviours (e.g. food intake and physical activity) and measurements of spatial accessibility to the associated facilities (e.g. food outlets and sport facilities). The aim of this study is to propose measurements of spatial accessibility to facilities on the regional scale, using aggregated data. We first used a potential accessibility model that partly makes it possible to overcome the limitations of the most frequently used indices such as the count of opportunities within a given neighbourhood. We then propose an extended model in order to take into account both home and work-based accessibility for a commuting population. Results Potential accessibility estimation provides a very different picture of the accessibility levels experienced by the population than the more classical "number of opportunities per census tract" index. The extended model for commuters increases the overall accessibility levels but this increase differs according to the urbanisation level. Strongest increases are observed in some rural municipalities with initial low accessibility levels. Distance to major urban poles seems to play an essential role. Conclusions Accessibility is a multi-dimensional concept that should integrate some aspects of travel behaviour. Our work supports the evidence that the choice of appropriate accessibility indices including both residential and non-residential environmental features is necessary. Such models have potential implications for providing relevant information to policy-makers in the field of public health. PMID:21219597

Contribution of Cerebellar Sensorimotor Adaptation to Hippocampal Spatial Memory

PubMed Central

Passot, Jean-Baptiste; Sheynikhovich, Denis; Duvelle, Éléonore; Arleo, Angelo

2012-01-01

Complementing its primary role in motor control, cerebellar learning has also a bottom-up influence on cognitive functions, where high-level representations build up from elementary sensorimotor memories. In this paper we examine the cerebellar contribution to both procedural and declarative components of spatial cognition. To do so, we model a functional interplay between the cerebellum and the hippocampal formation during goal-oriented navigation. We reinterpret and complete existing genetic behavioural observations by means of quantitative accounts that cross-link synaptic plasticity mechanisms, single cell and population coding properties, and behavioural responses. In contrast to earlier hypotheses positing only a purely procedural impact of cerebellar adaptation deficits, our results suggest a cerebellar involvement in high-level aspects of behaviour. In particular, we propose that cerebellar learning mechanisms may influence hippocampal place fields, by contributing to the path integration process. Our simulations predict differences in place-cell discharge properties between normal mice and L7-PKCI mutant mice lacking long-term depression at cerebellar parallel fibre-Purkinje cell synapses. On the behavioural level, these results suggest that, by influencing the accuracy of hippocampal spatial codes, cerebellar deficits may impact the exploration-exploitation balance during spatial navigation. PMID:22485133

Cox process representation and inference for stochastic reaction-diffusion processes

NASA Astrophysics Data System (ADS)

Schnoerr, David; Grima, Ramon; Sanguinetti, Guido

2016-05-01

Complex behaviour in many systems arises from the stochastic interactions of spatially distributed particles or agents. Stochastic reaction-diffusion processes are widely used to model such behaviour in disciplines ranging from biology to the social sciences, yet they are notoriously difficult to simulate and calibrate to observational data. Here we use ideas from statistical physics and machine learning to provide a solution to the inverse problem of learning a stochastic reaction-diffusion process from data. Our solution relies on a non-trivial connection between stochastic reaction-diffusion processes and spatio-temporal Cox processes, a well-studied class of models from computational statistics. This connection leads to an efficient and flexible algorithm for parameter inference and model selection. Our approach shows excellent accuracy on numeric and real data examples from systems biology and epidemiology. Our work provides both insights into spatio-temporal stochastic systems, and a practical solution to a long-standing problem in computational modelling.

Punishment and reputation in spatial public goods games.

PubMed

Brandt, Hannelore; Hauert, Christoph; Sigmund, Karl

2003-05-22

The puzzle of the emergence of cooperation between unrelated individuals is shared across diverse fields of behavioural sciences and economics. In this article we combine the public goods game originating in economics with evolutionary approaches traditionally used in biology. Instead of pairwise encounters, we consider the more complex case of groups of three interacting individuals. We show that territoriality is capable of promoting cooperative behaviour, as in the case of the Prisoner's Dilemma. Moreover, by adding punishment opportunities, the readiness to cooperate is greatly enhanced and asocial strategies can be largely suppressed. Finally, as soon as players carry a reputation for being willing or unwilling to punish, highly cooperative and fair outcomes are achieved. This group-beneficial result is obtained, intriguingly, by making individuals more likely to exploit their co-players if they can get away with it. Thus, less-cooperative individuals make more-cooperative societies.

Random behaviour, amplification processes and number of participants: How they contribute to the foraging properties of ants

NASA Astrophysics Data System (ADS)

Deneubourg, J. L.; Aron, S.; Goss, S.; Pasteels, J. M.; Duerinck, G.

1986-10-01

Two major types of foraging organisation in ants are described and compared, being illustrated with experimental data and mathematical models. The first concerns large colonies of identical, unspecialised foragers. The communication and interaction between foragers and their randomness generates collective and efficient structures. The second concerns small societies of deterministic and specialised foragers, rarely communicating together. The first organisation is discussed in relation to the different recruitment mechanisms, trail-following error, quality and degree of aggregation of food-sources, and territorial marking, and is the key to many types of collective behaviour in social insects. The second is discussed in relation to spatial specialisation, foraging density, individual learning and genetic programming. The two organisations may be associated in the same colony. The choice of organisation is discussed in relation to colony size and size and predictability of food sources.

Noise-induced effects in population dynamics

NASA Astrophysics Data System (ADS)

Spagnolo, Bernardo; Cirone, Markus; La Barbera, Antonino; de Pasquale, Ferdinando

2002-03-01

We investigate the role of noise in the nonlinear relaxation of two ecosystems described by generalized Lotka-Volterra equations in the presence of multiplicative noise. Specifically we study two cases: (i) an ecosystem with two interacting species in the presence of periodic driving; (ii) an ecosystem with a great number of interacting species with random interaction matrix. We analyse the interplay between noise and periodic modulation for case (i) and the role of the noise in the transient dynamics of the ecosystem in the presence of an absorbing barrier in case (ii). We find that the presence of noise is responsible for the generation of temporal oscillations and for the appearance of spatial patterns in the first case. In the other case we obtain the asymptotic behaviour of the time average of the ith population and discuss the effect of the noise on the probability distributions of the population and of the local field.

The Impact of Predation by Marine Mammals on Patagonian Toothfish Longline Fisheries

PubMed Central

Söffker, Marta; Trathan, Phil; Clark, James; Collins, Martin A.; Belchier, Mark; Scott, Robert

2015-01-01

Predatory interaction of marine mammals with longline fisheries is observed globally, leading to partial or complete loss of the catch and in some parts of the world to considerable financial loss. Depredation can also create additional unrecorded fishing mortality of a stock and has the potential to introduce bias to stock assessments. Here we aim to characterise depredation in the Patagonian toothfish (Dissostichus eleginoides) fishery around South Georgia focusing on the spatio-temporal component of these interactions. Antarctic fur seals (Arctocephalus gazella), sperm whales (Physeter macrocephalus), and orcas (Orcinus orca) frequently feed on fish hooked on longlines around South Georgia. A third of longlines encounter sperm whales, but loss of catch due to sperm whales is insignificant when compared to that due to orcas, which interact with only 5% of longlines but can take more than half of the catch in some cases. Orca depredation around South Georgia is spatially limited and focused in areas of putative migration routes, and the impact is compounded as a result of the fishery also concentrating in those areas at those times. Understanding the seasonal behaviour of orcas and the spatial and temporal distribution of “depredation hot spots” can reduce marine mammal interactions, will improve assessment and management of the stock and contribute to increased operational efficiency of the fishery. Such information is valuable in the effort to resolve the human-mammal conflict for resources. PMID:25738698

The impact of predation by marine mammals on patagonian toothfish longline fisheries.

PubMed

Söffker, Marta; Trathan, Phil; Clark, James; Collins, Martin A; Belchier, Mark; Scott, Robert

2015-01-01

Predatory interaction of marine mammals with longline fisheries is observed globally, leading to partial or complete loss of the catch and in some parts of the world to considerable financial loss. Depredation can also create additional unrecorded fishing mortality of a stock and has the potential to introduce bias to stock assessments. Here we aim to characterise depredation in the Patagonian toothfish (Dissostichus eleginoides) fishery around South Georgia focusing on the spatio-temporal component of these interactions. Antarctic fur seals (Arctocephalus gazella), sperm whales (Physeter macrocephalus), and orcas (Orcinus orca) frequently feed on fish hooked on longlines around South Georgia. A third of longlines encounter sperm whales, but loss of catch due to sperm whales is insignificant when compared to that due to orcas, which interact with only 5% of longlines but can take more than half of the catch in some cases. Orca depredation around South Georgia is spatially limited and focused in areas of putative migration routes, and the impact is compounded as a result of the fishery also concentrating in those areas at those times. Understanding the seasonal behaviour of orcas and the spatial and temporal distribution of "depredation hot spots" can reduce marine mammal interactions, will improve assessment and management of the stock and contribute to increased operational efficiency of the fishery. Such information is valuable in the effort to resolve the human-mammal conflict for resources.

Escape behaviour of birds in urban parks and cemeteries across Europe: Evidence of behavioural adaptation to human activity.

PubMed

Morelli, Federico; Mikula, Peter; Benedetti, Yanina; Bussière, Raphaël; Jerzak, Leszek; Tryjanowski, Piotr

2018-08-01

Urban environments are very heterogeneous, and birds living in the proximity of humans have to adapt to local conditions, e.g. by changing their behavioural response to potential predators. In this study, we tested whether the escape distance of birds (measured as flight initiation distance; FID) differed between parks and cemeteries, areas characterized by different microhabitat conditions and human conduct, that are determinants of animal behaviour at large spatial scales. While escape behaviour of park populations of birds was often examined, cemetery populations have not been studied to the same extent and a large-scale comparison is still missing. Overall, we collected 2139 FID estimates for 44 bird species recorded in 79 parks and 90 cemeteries in four European countries: Czech Republic, France, Italy and Poland. Mixed model procedure was applied to study escape behaviour in relation to type of area (park or cemetery), environmental characteristics (area size, coverage by trees, shrubs, grass, chapels, tombstones, flowerbeds, number of street lamps) and human activity (human density, pedestrians speed and ratio of men/women). Birds allowed people closer in cemeteries than in parks in all countries. This pattern was persistent even when focusing on intraspecific differences in FID between populations of the most common bird species. Escape distance of birds was negatively correlated with the size of parks/cemeteries, while positively associated with tombstone coverage and human density in both types of habitat. Our findings highlight the ability of birds to adapt their behaviour to different types of urban areas, based on local environmental conditions, including the character of human-bird interactions. Our results also suggest that this behavioural pattern may be widespread across urban landscapes. Copyright © 2018 Elsevier B.V. All rights reserved.

Intentional gaze shift to neglected space: a compensatory strategy during recovery after unilateral spatial neglect.

PubMed

Takamura, Yusaku; Imanishi, Maho; Osaka, Madoka; Ohmatsu, Satoko; Tominaga, Takanori; Yamanaka, Kentaro; Morioka, Shu; Kawashima, Noritaka

2016-11-01

Unilateral spatial neglect is a common neurological syndrome following predominantly right hemispheric stroke. While most patients lack insight into their neglect behaviour and do not initiate compensatory behaviours in the early recovery phase, some patients recognize it and start to pay attention towards the neglected space. We aimed to characterize visual attention capacity in patients with unilateral spatial neglect with specific focus on cortical processes underlying compensatory gaze shift towards the neglected space during the recovery process. Based on the Behavioural Inattention Test score and presence or absence of experience of neglect in their daily life from stroke onset to the enrolment date, participants were divided into USN+‰‰+ (do not compensate, n = 15), USN+ (compensate, n = 10), and right hemisphere damage groups (no neglect, n = 24). The patients participated in eye pursuit-based choice reaction tasks and were asked to pursue one of five horizontally located circular objects flashed on a computer display. The task consisted of 25 trials with 4-s intervals, and the order of highlighted objects was randomly determined. From the recorded eye tracking data, eye movement onset and gaze shift were calculated. To elucidate the cortical mechanism underlying behavioural results, electroencephalagram activities were recorded in three USN+‰‰+, 13 USN+ and eight patients with right hemisphere damage. We found that while lower Behavioural Inattention Test scoring patients (USN+‰‰+) showed gaze shift to non-neglected space, some higher scoring patients (USN+) showed clear leftward gaze shift at visual stimuli onset. Moreover, we found a significant correlation between Behavioural Inattention Test score and gaze shift extent in the unilateral spatial neglect group (r = -0.62, P < 0.01). Electroencephalography data clearly demonstrated that the extent of increase in theta power in the frontal cortex strongly correlated with the leftward gaze shift extent in the USN+‰‰+ and USN+ groups. Our results revealed a compensatory strategy (continuous attention to the neglected space) and its neural correlates in patients with unilateral spatial neglect. In conclusion, patients with unilateral spatial neglect who recognized their own neglect behaviour intentionally focused on the neglected space as a compensatory strategy to avoid careless oversight. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Setback Distances as a Conservation Tool in Wildlife-Human Interactions: Testing Their Efficacy for Birds Affected by Vehicles on Open-Coast Sandy Beaches

PubMed Central

Schlacher, Thomas A.; Weston, Michael A.; Lynn, David; Connolly, Rod M.

2013-01-01

In some wilderness areas, wildlife encounter vehicles disrupt their behaviour and habitat use. Changing driver behaviour has been proposed where bans on vehicle use are politically unpalatable, but the efficacy of vehicle setbacks and reduced speeds remains largely untested. We characterised bird-vehicle encounters in terms of driver behaviour and the disturbance caused to birds, and tested whether spatial buffers or lower speeds reduced bird escape responses on open beaches. Focal observations showed that: i) most drivers did not create sizeable buffers between their vehicles and birds; ii) bird disturbance was frequent; and iii) predictors of probability of flushing (escape) were setback distance and vehicle type (buses flushed birds at higher rates than cars). Experiments demonstrated that substantial reductions in bird escape responses required buffers to be wide (> 25 m) and vehicle speeds to be slow (< 30 km h-1). Setback distances can reduce impacts on wildlife, provided that they are carefully designed and derived from empirical evidence. No speed or distance combination we tested, however, eliminated bird responses. Thus, while buffers reduce response rates, they are likely to be much less effective than vehicle-free zones (i.e. beach closures), and rely on changes to current driver behaviour. PMID:24039711

Untangling the roles of microclimate, behaviour and physiological polymorphism in governing vulnerability of intertidal snails to heat stress.

PubMed

Dong, Yun-Wei; Li, Xiao-Xu; Choi, Francis M P; Williams, Gray A; Somero, George N; Helmuth, Brian

2017-05-17

Biogeographic distributions are driven by cumulative effects of smaller scale processes. Thus, vulnerability of animals to thermal stress is the result of physiological sensitivities to body temperature ( T b ), microclimatic conditions, and behavioural thermoregulation. To understand interactions among these variables, we analysed the thermal tolerances of three species of intertidal snails from different latitudes along the Chinese coast, and estimated potential T b in different microhabitats at each site. We then empirically determined the temperatures at which heart rate decreased sharply with rising temperature (Arrhenius breakpoint temperature, ABT) and at which it fell to zero (flat line temperature, FLT) to calculate thermal safety margins (TSM). Regular exceedance of FLT in sun-exposed microhabitats, a lethal effect, was predicted for only one mid-latitude site. However, ABTs of some individuals were exceeded at sun-exposed microhabitats in most sites, suggesting physiological impairment for snails with poor behavioural thermoregulation and revealing inter-individual variations (physiological polymorphism) of thermal limits. An autocorrelation analysis of T b showed that predictability of extreme temperatures was lowest at the hottest sites, indicating that the effectiveness of behavioural thermoregulation is potentially lowest at these sites. These results illustrate the critical roles of mechanistic studies at small spatial scales when predicting effects of climate change. © 2017 The Author(s).

Untangling the roles of microclimate, behaviour and physiological polymorphism in governing vulnerability of intertidal snails to heat stress

PubMed Central

Li, Xiao-xu; Choi, Francis M. P.; Williams, Gray A.; Somero, George N.; Helmuth, Brian

2017-01-01

Biogeographic distributions are driven by cumulative effects of smaller scale processes. Thus, vulnerability of animals to thermal stress is the result of physiological sensitivities to body temperature (Tb), microclimatic conditions, and behavioural thermoregulation. To understand interactions among these variables, we analysed the thermal tolerances of three species of intertidal snails from different latitudes along the Chinese coast, and estimated potential Tb in different microhabitats at each site. We then empirically determined the temperatures at which heart rate decreased sharply with rising temperature (Arrhenius breakpoint temperature, ABT) and at which it fell to zero (flat line temperature, FLT) to calculate thermal safety margins (TSM). Regular exceedance of FLT in sun-exposed microhabitats, a lethal effect, was predicted for only one mid-latitude site. However, ABTs of some individuals were exceeded at sun-exposed microhabitats in most sites, suggesting physiological impairment for snails with poor behavioural thermoregulation and revealing inter-individual variations (physiological polymorphism) of thermal limits. An autocorrelation analysis of Tb showed that predictability of extreme temperatures was lowest at the hottest sites, indicating that the effectiveness of behavioural thermoregulation is potentially lowest at these sites. These results illustrate the critical roles of mechanistic studies at small spatial scales when predicting effects of climate change. PMID:28469014

Hydrodynamic schooling of flapping swimmers

NASA Astrophysics Data System (ADS)

Becker, Alexander D.; Masoud, Hassan; Newbolt, Joel W.; Shelley, Michael; Ristroph, Leif

2015-10-01

Fish schools and bird flocks are fascinating examples of collective behaviours in which many individuals generate and interact with complex flows. Motivated by animal groups on the move, here we explore how the locomotion of many bodies emerges from their flow-mediated interactions. Through experiments and simulations of arrays of flapping wings that propel within a collective wake, we discover distinct modes characterized by the group swimming speed and the spatial phase shift between trajectories of neighbouring wings. For identical flapping motions, slow and fast modes coexist and correspond to constructive and destructive wing-wake interactions. Simulations show that swimming in a group can enhance speed and save power, and we capture the key phenomena in a mathematical model based on memory or the storage and recollection of information in the flow field. These results also show that fluid dynamic interactions alone are sufficient to generate coherent collective locomotion, and thus might suggest new ways to characterize the role of flows in animal groups.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Becker, Alexander D.; Masoud, Hassan; Newbolt, Joel W.

Fish schools and bird flocks are fascinating examples of collective behaviours in which many individuals generate and interact with complex flows. Motivated by animal groups on the move, here we explore how the locomotion of many bodies emerges from their flow-mediated interactions. Through experiments and simulations of arrays of flapping wings that propel within a collective wake, we discover distinct modes characterized by the group swimming speed and the spatial phase shift between trajectories of neighbouring wings. For identical flapping motions, slow and fast modes coexist and correspond to constructive and destructive wing–wake interactions. Simulations show that swimming in amore » group can enhance speed and save power, and we capture the key phenomena in a mathematical model based on memory or the storage and recollection of information in the flow field. Lastly, these results also show that fluid dynamic interactions alone are sufficient to generate coherent collective locomotion, and thus might suggest new ways to characterize the role of flows in animal groups.« less

Hydrodynamic schooling of flapping swimmers

DOE PAGES

Becker, Alexander D.; Masoud, Hassan; Newbolt, Joel W.; ...

2015-10-06

Fish schools and bird flocks are fascinating examples of collective behaviours in which many individuals generate and interact with complex flows. Motivated by animal groups on the move, here we explore how the locomotion of many bodies emerges from their flow-mediated interactions. Through experiments and simulations of arrays of flapping wings that propel within a collective wake, we discover distinct modes characterized by the group swimming speed and the spatial phase shift between trajectories of neighbouring wings. For identical flapping motions, slow and fast modes coexist and correspond to constructive and destructive wing–wake interactions. Simulations show that swimming in amore » group can enhance speed and save power, and we capture the key phenomena in a mathematical model based on memory or the storage and recollection of information in the flow field. Lastly, these results also show that fluid dynamic interactions alone are sufficient to generate coherent collective locomotion, and thus might suggest new ways to characterize the role of flows in animal groups.« less

The role of ecological dynamics in analysing performance in team sports.

PubMed

Vilar, Luís; Araújo, Duarte; Davids, Keith; Button, Chris

2012-01-01

Performance analysis is a subdiscipline of sports sciences and one-approach, notational analysis, has been used to objectively audit and describe behaviours of performers during different subphases of play, providing additional information for practitioners to improve future sports performance. Recent criticisms of these methods have suggested the need for a sound theoretical rationale to explain performance behaviours, not just describe them. The aim of this article was to show how ecological dynamics provides a valid theoretical explanation of performance in team sports by explaining the formation of successful and unsuccessful patterns of play, based on symmetry-breaking processes emerging from functional interactions between players and the performance environment. We offer the view that ecological dynamics is an upgrade to more operational methods of performance analysis that merely document statistics of competitive performance. In support of our arguments, we refer to exemplar data on competitive performance in team sports that have revealed functional interpersonal interactions between attackers and defenders, based on variations in the spatial positioning of performers relative to each other in critical performance areas, such as the scoring zones. Implications of this perspective are also considered for practice task design and sport development programmes.

Interaction of vortex ring with a stratified finite thickness interface

NASA Astrophysics Data System (ADS)

Advaith, S.; Manu, K. V.; Tinaikar, Aashay; Chetia, Utpal Kumar; Basu, Saptarshi

2017-09-01

This work experimentally investigates the dynamics of interaction between a propagating vortex ring and density stratified interface of finite thickness. The flow evolution has been quantified using a high speed shadowgraph technique and particle image velocimetry. The spatial and temporal behaviours of the vortex in the near and far field of the interface and the plume structure formed due to buoyancy are investigated systematically by varying the vortex strength (Reynolds number, Re) and the degree of stratification (Atwood number, At). Maximum penetration length (Lpmax) of the vortex ring through the interface is measured over a range of Reynolds (1350 ≤ Re ≤ 4600) and Richardson (0.1 ≤ Ri ≤ 4) numbers. It is found that for low Froude number values, the maximum penetration length varies linearly with the Froude number as in the study of Orlandi et al. ["Vortex rings descending in a stratified fluid," Phys. Fluids 10, 2819-2827 (1998)]. However, for high Reynolds and Richardson numbers (Ri), anomalous behaviour in maximum penetration is observed. The Lpmax value is used to characterize the vortex-interface interactions into non-penetrative, partially-penetrative, and extensively penetrative regimes. Flow visualization revealed the occurrence of short-wavelength instability of a plume structure, particularly in a partially penetrative regime. Fluid motion exhibits chaotic behaviour in an extensively penetrative regime. Detailed analyses of plume structure propagation are performed by measuring the plume length and plume rise. Appropriate scaling for the plume length and plume rise is derived, which allows universal collapse of the data for different flow conditions. Some information concerning the instability of the plume structure and decay of the vortex ring is obtained using proper orthogonal decomposition.

Towards evenly distributed grazing patterns: including social context in sheep management strategies.

PubMed

di Virgilio, Agustina; Morales, Juan Manuel

2016-01-01

Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals' foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals' space use patterns, our aim was to explore the potential effects of including animals' social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock) grazing on three different paddocks (with sizes from 80 to 1000 Ha) during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets), age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females) used more intensively the most preferred areas and low-ranked (i.e., yearlings) used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour). Discussion. Although homogenization and segregation of flocks by classes are common practices to increase flock productivity, we are proposing an alternative that employs behavioural interactions in heterogeneous flocks to generate more evenly distributed grazing patterns. This practice can be combined with other practices such as rotational grazing and guardian dogs (to decrease mortality levels that may be generated by sheep grazing on more risky habitats). This does not imply any modifications of livestock stocking rates and densities or any additional investments for labour and materials. Considering livestock behaviour is critical for the design of sustainable management practices that balance landscape conservation and livestock productivity.

Changes in practice task constraints shape decision-making behaviours of team games players.

PubMed

Correia, Vanda; Araújo, Duarte; Duarte, Ricardo; Travassos, Bruno; Passos, Pedro; Davids, Keith

2012-05-01

This study examined the effects of manipulating relative positioning between defenders (initial distance apart) on emergent decision-making and actions in a 1 vs. 2 rugby union performance sub-phase. Twelve experienced youth players performed 80 trials of a 1 (attacker) vs. 2 (defenders) practice task in which the starting distance between defenders was systematically decreased. Movement displacement trajectories of participants were video recorded to obtain 2D positional data. The independent variable was the starting distance between defenders and dependent variables were: (i) performance outcome (try or tackle), (ii) mean speed of all players during performance, and (iii), time between the first crossover and the end of the trial. Repeated measures ANOVA was used to compare the effects of different starting distances on performance. Shorter starting distances between defenders were associated with a higher frequency of effective tackle outcomes, lower mean speeds of all participants, and a greater time period between the first crossover and the end of the trial. Decision-making behaviours emerged as a function of changes in participants' spatial location during performance. This observation supports the importance of manipulating key spatial-temporal variables in designing representative practice task constraints that induce functional player-environment interactions in team sports training. Copyright © 2011 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Polysoaps: Configurations and Elasticity

NASA Astrophysics Data System (ADS)

Halperin, A.

1997-03-01

Simple polymers are very long, flexible, linear molecules. Amphiphiles, soaps, are small molecules comprising of a part that prefers water over oil and a part that prefers oil over water. By combining the two we arrive at an interesting, little explored, class of materials: Polysoaps. These comprise of a water soluble backbone incorporating, at intervals, covalently bound amphiphilic monomers. In water, the polymerised amphiphiles aggregate into self assembled units known as micelles. This induces a dramatic modification of the spatial configurations of the polymers. What were featureless random coils now exhibit intramolecular, hierachial self organisation. Due to this self organisation it is necessary to modify the paradigms describing the large scale behaviour of these polymers: Their configurations, dimensions and elasticity. Understanding the behaviour of these polymers is of practical interest because of their wide range of industrial applications, ranging from cosmetics to paper coating. It is of fundamental interest because polysoaps are characterised by a rugged free energy landscape that is reminiscent of complex systems such as proteins and glasses. The talk concerns theoretical arguments regarding the following issues: (i) The design parameters that govern the spatial configurations of the polysoaps, (ii) The interaction between polysoaps and free amphiphiles, (iii) The effect of the intramolecular self organisation on the elasticity of the chains.

Linking movement and oviposition behaviour to spatial population distribution in the tree hole mosquito Ochlerotatus triseriatus.

PubMed

Ellis, Alicia M

2008-01-01

1. Researchers often use the spatial distribution of insect offspring as a measure of adult oviposition preferences, and then make conclusions about the consequences of these preferences for population growth and the relationship between life-history traits (e.g. oviposition preference and offspring performance). However, several processes other than oviposition preference can generate spatial patterns of offspring density (e.g. dispersal limitations, spatially heterogeneous mortality rates). Incorrectly assuming that offspring distributions reflect oviposition preferences may therefore compromise our ability to understand the mechanisms determining population distributions and the relationship between life-history traits. 2. The purpose of this study was to perform an empirical study at the whole-system scale to examine the movement and oviposition behaviours of the eastern tree hole mosquito Ochlerotatus triseriatus (Say) and test the importance of these behaviours in determining population distribution relative to other mechanisms. 3. A mark-release-recapture experiment was performed to distinguish among the following alternative hypotheses that may explain a previously observed aggregated distribution of tree hole mosquito offspring: (H(1)) mosquitoes prefer habitats with particular vegetation characteristics and these preferences determine the distribution of their offspring; (H(2)) mosquitoes distribute their eggs randomly or evenly throughout their environment, but spatial differences in developmental success generate an aggregated pattern of larval density; (H(3)) mosquitoes randomly colonize habitats, but have limited dispersal capability causing them to distribute offspring where founder populations were established; (H(4)) wind or other environmental factors may lead to passive aggregation, or spatial heterogeneity in adult mortality (H(5)), rather than dispersal, generates clumped offspring distributions. 4. Results indicate that the distribution of tree hole mosquito larvae is determined in part by adult habitat selection (H(1)), but do not exclude additional effects from passive aggregation (H(4)), or spatial patterns in adult mortality (H(5)). 5. This research illustrates the importance of studying oviposition behaviour at the population scale to better evaluate its relative importance in determining population distribution and dynamics. Moreover, this study demonstrates the importance of linking behavioural and population dynamics for understanding evolutionary relationships among life-history traits (e.g. preference and offspring performance) and predicting when behaviour will be important in determining population phenomena.

Light drinking versus abstinence in pregnancy – behavioural and cognitive outcomes in 7-year-old children: a longitudinal cohort study

PubMed Central

Kelly, Y; Iacovou, M; Quigley, MA; Gray, R; Wolke, D; Kelly, J; Sacker, A

2013-01-01

Objective To assess whether light drinking in pregnancy is linked to unfavourable developmental outcomes in children. Design Prospective population-based cohort. Setting UK. Population Ten thousand five hundred and thirty-four 7-year-olds. Methods Quasi-experimental using propensity score matching (PSM) to compare children born to light (up to 2 units per week) and non-drinkers. Main outcome measures Behavioural difficulties rated by parents and teachers; cognitive test scores for reading, maths and spatial skills. Results Ordinary least squares (OLS) regression and PSM analyses are presented. For behavioural difficulties, unadjusted estimates for percentage standard deviation (SD) score differences ranged from 2 to 14%. On adjustment for potential confounders, differences were attenuated, with a loss of statistical significance, except for teacher-rated boys' difficulties. For boys, parent-rated behavioural difficulties: unadjusted, −11.5; OLS, −4.3; PSM, −6.8; teacher-rated behavioural difficulties: unadjusted, −13.9; OLS, −9.6; PSM, −10.8. For girls, parent-rated behavioural difficulties: unadjusted, −9.6; OLS, −2.9; PSM, −4.5; teacher-rated behavioural difficulties: unadjusted, −2.4; OLS, 4.9; PSM, 3.9. For cognitive test scores, unadjusted estimates for differences ranged between 12 and 21% of an SD score for reading, maths and spatial skills. After adjustment for potential confounders, estimates were reduced, but remained statistically significantly different for reading and for spatial skills in boys. For boys, reading: unadjusted, 20.9; OLS, 8.3; PSM, 7.3; maths: unadjusted, 14.7; OLS, 5.0; PSM, 6.5; spatial skills: unadjusted, 16.2; OLS, 7.6; PSM, 8.1. For girls, reading: unadjusted, 11.6; OLS, −0.3; PSM, −0.5; maths: unadjusted, 12.9; OLS, 4.3; PSM, 3.9; spatial skills: unadjusted, 16.2; OLS, 7.7; PSM, 6.4. Conclusion The findings suggest that light drinking during pregnancy is not linked to developmental problems in mid-childhood. These findings support current UK Department of Health guidelines on drinking during pregnancy. PMID:23590126

Light drinking versus abstinence in pregnancy - behavioural and cognitive outcomes in 7-year-old children: a longitudinal cohort study.

PubMed

Kelly, Y; Iacovou, M; Quigley, M A; Gray, R; Wolke, D; Kelly, J; Sacker, A

2013-10-01

To assess whether light drinking in pregnancy is linked to unfavourable developmental outcomes in children. Prospective population-based cohort. UK. Ten thousand five hundred and thirty-four 7-year-olds. Quasi-experimental using propensity score matching (PSM) to compare children born to light (up to 2 units per week) and non-drinkers. Behavioural difficulties rated by parents and teachers; cognitive test scores for reading, maths and spatial skills. Ordinary least squares (OLS) regression and PSM analyses are presented. For behavioural difficulties, unadjusted estimates for percentage standard deviation (SD) score differences ranged from 2 to 14%. On adjustment for potential confounders, differences were attenuated, with a loss of statistical significance, except for teacher-rated boys' difficulties. For boys, parent-rated behavioural difficulties: unadjusted, -11.5; OLS, -4.3; PSM, -6.8; teacher-rated behavioural difficulties: unadjusted, -13.9; OLS, -9.6; PSM, -10.8. For girls, parent-rated behavioural difficulties: unadjusted, -9.6; OLS, -2.9; PSM, -4.5; teacher-rated behavioural difficulties: unadjusted, -2.4; OLS, 4.9; PSM, 3.9. For cognitive test scores, unadjusted estimates for differences ranged between 12 and 21% of an SD score for reading, maths and spatial skills. After adjustment for potential confounders, estimates were reduced, but remained statistically significantly different for reading and for spatial skills in boys. For boys, reading: unadjusted, 20.9; OLS, 8.3; PSM, 7.3; maths: unadjusted, 14.7; OLS, 5.0; PSM, 6.5; spatial skills: unadjusted, 16.2; OLS, 7.6; PSM, 8.1. For girls, reading: unadjusted, 11.6; OLS, -0.3; PSM, -0.5; maths: unadjusted, 12.9; OLS, 4.3; PSM, 3.9; spatial skills: unadjusted, 16.2; OLS, 7.7; PSM, 6.4. The findings suggest that light drinking during pregnancy is not linked to developmental problems in mid-childhood. These findings support current UK Department of Health guidelines on drinking during pregnancy. © 2013 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2013 RCOG.

Effects of large Saduria entomon (Isopoda) on spatial distribution of their small S. entomon and Monoporeia affinis (Amphipoda) prey.

PubMed

Sparrevik, Erik; Leonardsson, Kjell

1995-02-01

We performed laboratory experiments to investigate the effects of predator avoidance and numerical effects of predation on spatial distribution of small Saduria entomon (Isopoda) and Monoporeia affinis (Amphipoda), with large S. entomon as predators. The horizontal distribution and mortality of the prey species, separately and together, were studied in aquaria with a spatial horizontal refuge. We also estimated effects of refuge on mortality of small S. entomon and M. affinis by experiments without the refuge net. In addition, we investigated whether predation risk from large S. entomon influenced the swimming activity of M. affinis, to clarify the mechanisms behind the spatial distribution. Both small S. entomon and M. affinis avoided large S. entomon. The avoidance behaviour of M. fffinis contributed about 10 times more to the high proportion in the refuge than numerical effects of predation. Due to the low mortality of small S. entomon the avoidance behaviour of this species was even more important for the spatial distribution. The combined effect of avoidance behaviour and predation in both species was aggregation, producting a positive correlation between the species in density. M. affinis showed two types of avoidance behaviour. In the activity experiments they reduced activity by 36% and buried themselves in the sediment. In the refuge experiments we also observed avoidance behaviour with the emigration rate from the predator compartment being twice the immigration rate. The refuge did not lower predation mortality in M. affinis, probably due to the small scale of the experimental units in relation to the mobility of the species. Predation mortality in small S. entomon was higher in absence of a refuge and especially high in absence of M. affinis.

Predatory beetles facilitate plant growth by driving earthworms to lower soil layers.

PubMed

Zhao, Chuan; Griffin, John N; Wu, Xinwei; Sun, Shucun

2013-07-01

Theory suggests that predators of soil-improving, plant-facilitating detritivores (e.g. earthworms) should suppress plant growth via a negative tri-trophic cascade, but the empirical evidence is still largely lacking. We tested this prediction in an alpine meadow on the Tibetan Plateau by manipulating predatory beetles (presence/absence) and quantifying (i) direct effects on the density and behaviour of earthworms; and (ii) indirect effects on soil properties and above-ground plant biomass. In the absence of predators, earthworms improved soil properties, but did not significantly affect plant biomass. Surprisingly, the presence of predators strengthened the positive effect of earthworms on soil properties leading to the emergence of a positive indirect effect of predators on plant biomass. We attribute this counterintuitive result to: (i) the inability of predators to suppress overall earthworm density; and (ii) the predator-induced earthworm habitat shift from the upper to lower soil layer that enhanced their soil-modifying, plant-facilitating, effects. Our results reveal that plant-level consequences of predators as transmitted through detritivores can hinge on behaviour-mediated indirect interactions that have the potential to overturn predictions based solely on trophic interactions. This work calls for a closer examination of the effects of predators in detritus food webs and the development of spatially explicit theory capable of predicting the occurrence and consequences of predator-induced detritivore behavioural shifts. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

Crossover between two- and three-dimensional turbulence in spatial mixing layers

NASA Astrophysics Data System (ADS)

Biancofiore, Luca

2016-11-01

We investigate how the domain depth affects the turbulent behaviour in spatially developing mixing layers by means of large-eddy simulations (LES) based on a spectral vanishing viscosity technique. Analyses of spectra of the vertical velocity, of Lumley's diagrams, of the turbulent kinetic energy and of the vortex stretching show that a two-dimensional behaviour of the turbulence is promoted in spatial mixing layers by constricting the fluid motion in one direction. This finding is in agreement with previous works on turbulent systems constrained by a geometric anisotropy, pioneered by Smith, Chasnov & Waleffe. We observe that the growth of the momentum thickness along the streamwise direction is damped in a confined domain. A full two-dimensional turbulent behaviour is observed when the momentum thickness is of the same order of magnitude as the confining scale.

A Generic Individual-Based Spatially Explicit Model as a Novel Tool for Investigating Insect-Plant Interactions: A Case Study of the Behavioural Ecology of Frugivorous Tephritidae

PubMed Central

Wang, Ming; Cribb, Bronwen; Clarke, Anthony R.; Hanan, Jim

2016-01-01

Computational modelling of mechanisms underlying processes in the real world can be of great value in understanding complex biological behaviours. Uptake in general biology and ecology has been rapid. However, it often requires specific data sets that are overly costly in time and resources to collect. The aim of the current study was to test whether a generic behavioural ecology model constructed using published data could give realistic outputs for individual species. An individual-based model was developed using the Pattern-Oriented Modelling (POM) strategy and protocol, based on behavioural rules associated with insect movement choices. Frugivorous Tephritidae (fruit flies) were chosen because of economic significance in global agriculture and the multiple published data sets available for a range of species. The Queensland fruit fly (Qfly), Bactrocera tryoni, was identified as a suitable individual species for testing. Plant canopies with modified architecture were used to run predictive simulations. A field study was then conducted to validate our model predictions on how plant architecture affects fruit flies’ behaviours. Characteristics of plant architecture such as different shapes, e.g., closed-canopy and vase-shaped, affected fly movement patterns and time spent on host fruit. The number of visits to host fruit also differed between the edge and centre in closed-canopy plants. Compared to plant architecture, host fruit has less contribution to effects on flies’ movement patterns. The results from this model, combined with our field study and published empirical data suggest that placing fly traps in the upper canopy at the edge should work best. Such a modelling approach allows rapid testing of ideas about organismal interactions with environmental substrates in silico rather than in vivo, to generate new perspectives. Using published data provides a saving in time and resources. Adjustments for specific questions can be achieved by refinement of parameters based on targeted experiments. PMID:26999285

High levels of maternally transferred mercury disrupt magnetic responses of snapping turtle hatchlings (Chelydra serpentina).

PubMed

Landler, Lukas; Painter, Michael S; Coe, Brittney Hopkins; Youmans, Paul W; Hopkins, William A; Phillips, John B

2017-09-01

The Earth's magnetic field is involved in spatial behaviours ranging from long-distance migration to non-goal directed behaviours, such as spontaneous magnetic alignment (SMA). Mercury is a harmful pollutant most often generated from anthropogenic sources that can bio-accumulate in animal tissue over a lifetime. We compared SMA of hatchling snapping turtles from mothers captured at reference (i.e., low mercury) and mercury contaminated sites. Reference turtles showed radio frequency-dependent SMA along the north-south axis, consistent with previous studies of SMA, while turtles with high levels of maternally inherited mercury failed to show consistent magnetic alignment. In contrast, there was no difference between reference and mercury exposed turtles on standard performance measures. The magnetic field plays an important role in animal orientation behaviour and may also help to integrate spatial information from a variety of sensory modalities. As a consequence, mercury may compromise the performance of turtles in a wide variety of spatial tasks. Future research is needed to determine the threshold for mercury effects on snapping turtles, whether mercury exposure compromises spatial behaviour of adult turtles, and whether mercury has a direct effect on the magnetoreception mechanism(s) that mediate SMA or a more general effect on the nervous system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spatio-temporal networks: reachability, centrality and robustness.

PubMed

Williams, Matthew J; Musolesi, Mirco

2016-06-01

Recent advances in spatial and temporal networks have enabled researchers to more-accurately describe many real-world systems such as urban transport networks. In this paper, we study the response of real-world spatio-temporal networks to random error and systematic attack, taking a unified view of their spatial and temporal performance. We propose a model of spatio-temporal paths in time-varying spatially embedded networks which captures the property that, as in many real-world systems, interaction between nodes is non-instantaneous and governed by the space in which they are embedded. Through numerical experiments on three real-world urban transport systems, we study the effect of node failure on a network's topological, temporal and spatial structure. We also demonstrate the broader applicability of this framework to three other classes of network. To identify weaknesses specific to the behaviour of a spatio-temporal system, we introduce centrality measures that evaluate the importance of a node as a structural bridge and its role in supporting spatio-temporally efficient flows through the network. This exposes the complex nature of fragility in a spatio-temporal system, showing that there is a variety of failure modes when a network is subject to systematic attacks.

Non-linear Min protein interactions generate harmonics that signal mid-cell division in Escherichia coli

PubMed Central

Walsh, James C.; Angstmann, Christopher N.; Duggin, Iain G.

2017-01-01

The Min protein system creates a dynamic spatial pattern in Escherichia coli cells where the proteins MinD and MinE oscillate from pole to pole. MinD positions MinC, an inhibitor of FtsZ ring formation, contributing to the mid-cell localization of cell division. In this paper, Fourier analysis is used to decompose experimental and model MinD spatial distributions into time-dependent harmonic components. In both experiment and model, the second harmonic component is responsible for producing a mid-cell minimum in MinD concentration. The features of this harmonic are robust in both experiment and model. Fourier analysis reveals a close correspondence between the time-dependent behaviour of the harmonic components in the experimental data and model. Given this, each molecular species in the model was analysed individually. This analysis revealed that membrane-bound MinD dimer shows the mid-cell minimum with the highest contrast when averaged over time, carrying the strongest signal for positioning the cell division ring. This concurs with previous data showing that the MinD dimer binds to MinC inhibiting FtsZ ring formation. These results show that non-linear interactions of Min proteins are essential for producing the mid-cell positioning signal via the generation of second-order harmonic components in the time-dependent spatial protein distribution. PMID:29040283

Predator-prey-subsidy population dynamics on stepping-stone domains with dispersal delays.

PubMed

Eide, Ragna M; Krause, Andrew L; Fadai, Nabil T; Van Gorder, Robert A

2018-08-14

We examine the role of the travel time of a predator along a spatial network on predator-prey population interactions, where the predator is able to partially or fully sustain itself on a resource subsidy. The impact of access to food resources on the stability and behaviour of the predator-prey-subsidy system is investigated, with a primary focus on how incorporating travel time changes the dynamics. The population interactions are modelled by a system of delay differential equations, where travel time is incorporated as discrete delay in the network diffusion term in order to model time taken to migrate between spatial regions. The model is motivated by the Arctic ecosystem, where the Arctic fox consumes both hunted lemming and scavenged seal carcass. The fox travels out on sea ice, in addition to quadrennially migrating over substantial distances. We model the spatial predator-prey-subsidy dynamics through a "stepping-stone" approach. We find that a temporal delay alone does not push species into extinction, but rather may stabilize or destabilize coexistence equilibria. We are able to show that delay can stabilize quasi-periodic or chaotic dynamics, and conclude that the incorporation of dispersal delay has a regularizing effect on dynamics, suggesting that dispersal delay can be proposed as a solution to the paradox of enrichment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Avoiding pitfalls in estimating heritability with the common options approach

PubMed Central

Danchin, Etienne; Wajnberg, Eric; Wagner, Richard H.

2014-01-01

In many circumstances, heritability estimates are subject to two potentially interacting pitfalls: the spatial and the regression to the mean (RTM) fallacies. The spatial fallacy occurs when the set of potential movement options differs among individuals according to where individuals depart. The RTM fallacy occurs when extreme measurements are followed by measurements that are closer to the mean. We simulated data from the largest published heritability study of a behavioural trait, colony size choice, to examine the operation of the two fallacies. We found that spurious heritabilities are generated under a wide range of conditions both in experimental and correlative estimates of heritability. Classically designed cross-foster experiments can actually increase the frequency of spurious heritabilities. Simulations showed that experiments providing all individuals with the identical set of options, such as by fostering all offspring in the same breeding location, are immune to the two pitfalls. PMID:24865284

Constraining Distributed Catchment Models by Incorporating Perceptual Understanding of Spatial Hydrologic Behaviour

NASA Astrophysics Data System (ADS)

Hutton, Christopher; Wagener, Thorsten; Freer, Jim; Han, Dawei

2016-04-01

Distributed models offer the potential to resolve catchment systems in more detail, and therefore simulate the hydrological impacts of spatial changes in catchment forcing (e.g. landscape change). Such models tend to contain a large number of poorly defined and spatially varying model parameters which are therefore computationally expensive to calibrate. Insufficient data can result in model parameter and structural equifinality, particularly when calibration is reliant on catchment outlet discharge behaviour alone. Evaluating spatial patterns of internal hydrological behaviour has the potential to reveal simulations that, whilst consistent with measured outlet discharge, are qualitatively dissimilar to our perceptual understanding of how the system should behave. We argue that such understanding, which may be derived from stakeholder knowledge across different catchments for certain process dynamics, is a valuable source of information to help reject non-behavioural models, and therefore identify feasible model structures and parameters. The challenge, however, is to convert different sources of often qualitative and/or semi-qualitative information into robust quantitative constraints of model states and fluxes, and combine these sources of information together to reject models within an efficient calibration framework. Here we present the development of a framework to incorporate different sources of data to efficiently calibrate distributed catchment models. For each source of information, an interval or inequality is used to define the behaviour of the catchment system. These intervals are then combined to produce a hyper-volume in state space, which is used to identify behavioural models. We apply the methodology to calibrate the Penn State Integrated Hydrological Model (PIHM) at the Wye catchment, Plynlimon, UK. Outlet discharge behaviour is successfully simulated when perceptual understanding of relative groundwater levels between lowland peat, upland peat and valley slopes within the catchment are used to identify behavioural models. The process of converting qualitative information into quantitative constraints forces us to evaluate the assumptions behind our perceptual understanding in order to derive robust constraints, and therefore fairly reject models and avoid type II errors. Likewise, consideration needs to be given to the commensurability problem when mapping perceptual understanding to constrain model states.

Behaviour-Related Scalar Habitat Use by Cape Buffalo (Syncerus caffer caffer)

PubMed Central

Bennitt, Emily; Bonyongo, Mpaphi Casper; Harris, Stephen

2015-01-01

Studies of habitat use by animals must consider behavioural resource requirements at different scales, which could influence the functional value of different sites. Using Cape buffalo (Syncerus caffer caffer) in the Okavango Delta, Botswana, we tested the hypotheses that behaviour affected use between and within habitats, hereafter referred to as macro- and microhabitats, respectively. We fitted GPS-enabled collars to fifteen buffalo and used the distances and turning angles between consecutive fixes to cluster the resulting data into resting, grazing, walking and relocating behaviours. Distance to water and six vegetation characteristic variables were recorded in sites used for each behaviour, except for relocating, which occurred too infrequently. We used multilevel binomial and multinomial logistic regressions to identify variables that characterised seasonally-preferred macrohabitats and microhabitats used for different behaviours. Our results showed that macrohabitat use was linked to behaviour, although this was least apparent during the rainy season, when resources were most abundant. Behaviour-related microhabitat use was less significant, but variation in forage characteristics could predict some behaviour within all macrohabitats. The variables predicting behaviour were not consistent, but resting and grazing sites were more readily identifiable than walking sites. These results highlight the significance of resting, as well as foraging, site availability in buffalo spatial processes. Our results emphasise the importance of considering several behaviours and scales in studies of habitat use to understand the links between environmental resources and animal behavioural and spatial ecology. PMID:26673623

Development of a novel coding scheme (SABICS) to record nurse-child interactive behaviours in a community dental preventive intervention.

PubMed

Zhou, Yuefang; Cameron, Elaine; Forbes, Gillian; Humphris, Gerry

2012-08-01

To develop and validate the St Andrews Behavioural Interaction Coding Scheme (SABICS): a tool to record nurse-child interactive behaviours. The SABICS was developed primarily from observation of video recorded interactions; and refined through an iterative process of applying the scheme to new data sets. Its practical applicability was assessed via implementation of the scheme on specialised behavioural coding software. Reliability was calculated using Cohen's Kappa. Discriminant validity was assessed using logistic regression. The SABICS contains 48 codes. Fifty-five nurse-child interactions were successfully coded through administering the scheme on The Observer XT8.0 system. Two visualization results of interaction patterns demonstrated the scheme's capability of capturing complex interaction processes. Cohen's Kappa was 0.66 (inter-coder) and 0.88 and 0.78 (two intra-coders). The frequency of nurse behaviours, such as "instruction" (OR = 1.32, p = 0.027) and "praise" (OR = 2.04, p = 0.027), predicted a child receiving the intervention. The SABICS is a unique system to record interactions between dental nurses and 3-5 years old children. It records and displays complex nurse-child interactive behaviours. It is easily administered and demonstrates reasonable psychometric properties. The SABICS has potential for other paediatric settings. Its development procedure may be helpful for other similar coding scheme development. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

The nature of peer-directed behaviours in children with profound intellectual and multiple disabilities and its relationship with social scaffolding behaviours of the direct support worker.

PubMed

Nijs, S; Vlaskamp, C; Maes, B

2016-01-01

The multiple and complex disabilities of persons with profound intellectual and multiple disabilities (PIMD) form a barrier for peer interactions and peer-directed behaviours. In this study, we further explore the nature of peer-directed behaviours in persons with PIMD and its relationship with social scaffolding behaviour of direct support workers (DSWs). Fourteen dyads of children with PIMD, who knew each other for at least 12 months, participated. They were sitting in close proximity while they were filmed with and without the presence of the DSW. Video recordings were coded continuously making use of observation schemes for the peer-directed behaviours of the children and the peer interaction influencing behaviours of the DSW. Significantly more singular peer-directed behaviour (without DSW: 18.00%; with DSW: 3.81%) was observed than multiple peer-directed behaviour (without DSW: 4.01%; with DSW: 0.52%). The amount of time the singular and multiple peer-directed behaviours were observed was significantly lower in the presence of a DSW. When the DSW shows peer interaction influencing behaviour, it was mostly social scaffolding behaviour (2.17%). The conditional probability of observing social scaffolding behaviour in the 10 s following on singular peer-directed behaviour was 0.02 with a Yule's Q of 0.04 and following on multiple peer-directed behaviour 0.04 with a Yule's Q of 0.33. The way in which peer interactions in children with PIMD are defined could have an impact on the amount of observed peer-directed behaviours and on the effect of the social scaffolding behaviours presented by DSW. © 2015 John Wiley & Sons Ltd.

Genetic composition of social groups influences male aggressive behaviour and fitness in natural genotypes of Drosophila melanogaster

PubMed Central

Saltz, Julia B.

2013-01-01

Indirect genetic effects (IGEs) describe how an individual's behaviour—which is influenced by his or her genotype—can affect the behaviours of interacting individuals. IGE research has focused on dyads. However, insights from social networks research, and other studies of group behaviour, suggest that dyadic interactions are affected by the behaviour of other individuals in the group. To extend IGE inferences to groups of three or more, IGEs must be considered from a group perspective. Here, I introduce the ‘focal interaction’ approach to study IGEs in groups. I illustrate the utility of this approach by studying aggression among natural genotypes of Drosophila melanogaster. I chose two natural genotypes as ‘focal interactants’: the behavioural interaction between them was the ‘focal interaction’. One male from each focal interactant genotype was present in every group, and I varied the genotype of the third male—the ‘treatment male’. Genetic variation in the treatment male's aggressive behaviour influenced the focal interaction, demonstrating that IGEs in groups are not a straightforward extension of IGEs measured in dyads. Further, the focal interaction influenced male mating success, illustrating the role of IGEs in behavioural evolution. These results represent the first manipulative evidence for IGEs at the group level. PMID:24068359

Predicted Spatial Spread of Canine Rabies in Australia

PubMed Central

Fleming, Peter J. S.; Ward, Michael P.; Davis, Stephen A.

2017-01-01

Modelling disease dynamics is most useful when data are limited. We present a spatial transmission model for the spread of canine rabies in the currently rabies-free wild dog population of Australia. The introduction of a sub-clinically infected dog from Indonesia is a distinct possibility, as is the spillover infection of wild dogs. Ranges for parameters were estimated from the literature and expert opinion, or set to span an order of magnitude. Rabies was judged to have spread spatially if a new infectious case appeared 120 km from the index case. We found 21% of initial value settings resulted in canine rabies spreading 120km, and on doing so at a median speed of 67 km/year. Parameters governing dog movements and behaviour, around which there is a paucity of knowledge, explained most of the variance in model outcomes. Dog density, especially when interactions with other parameters were included, explained some of the variance in whether rabies spread 120km, but dog demography (mean lifespan and mean replacement period) had minimal impact. These results provide a clear research direction if Australia is to improve its preparedness for rabies. PMID:28114327

Accelerated behavioural development changes fine-scale search behaviour and spatial memory in honey bees (Apis mellifera L.).

PubMed

Ushitani, Tomokazu; Perry, Clint J; Cheng, Ken; Barron, Andrew B

2016-02-01

Normally, worker honey bees (Apis mellifera) begin foraging when more than 2 weeks old as adults, but if individual bees or the colony is stressed, bees often begin foraging precociously. Here, we examined whether bees that accelerated their behavioural development to begin foraging precociously differed from normal-aged foragers in cognitive performance. We used a social manipulation to generate precocious foragers from small experimental colonies and tested their performance in a free-flight visual reversal learning task, and a test of spatial memory. To assess spatial memory, bees were trained to learn the location of a small sucrose feeder within an array of three landmarks. In tests, the feeder and one landmark were removed and the search behaviour of the bees was recorded. Performance of precocious and normal-aged foragers did not differ in a visual reversal learning task, but the two groups showed a clear difference in spatial memory. Flight behaviour suggested normal-aged foragers were better able to infer the position of the removed landmark and feeder relative to the remaining landmarks than precocious foragers. Previous studies have documented the cognitive decline of old foragers, but this is the first suggestion of a cognitive deficit in young foragers. These data imply that worker honey bees continue their cognitive development during the adult stage. These findings may also help to explain why precocious foragers perform quite poorly as foragers and have a higher than normal loss rate. © 2016. Published by The Company of Biologists Ltd.

Evaluation of chronic alcohol self-administration by a 3-bottle choice paradigm in adult male rats. Effects on behavioural reactivity, spatial learning and reference memory.

PubMed

Cacace, Silvana; Plescia, Fulvio; La Barbera, Marco; Cannizzaro, Carla

2011-06-01

Chronic ethanol consumption is able to modify emotional behaviour and cognition in humans. In particular, the effects exerted by alcohol may depend on doses, time and modalities of administration. In this study we investigated, in adult male rats, ethanol self-administration and preference patterns using a 3-bottle choice paradigm with water, 10% ethanol solution, and white wine (10%, v/v), along a four-week period. The influence of alcohol free-access on novelty-induced explorative behaviour in the open field, and on spatial learning and reference memory in the Morris water maze was also evaluated. Our results indicate that: (i) rats show a higher preference for alcohol, in the first two weeks of the paradigm, displaying a higher consumption of 10% ethanol solution than white wine; in the last two weeks, they reduce their alcoholic preference, drinking the same moderate amounts of the two alcoholic beverages; (ii) at the fourth week of the free-access paradigm rats show a high explorative behaviour in the central squares of the open field and an improvement in spatial information processing in the new-place learning task of the Morris water maze. In conclusion our data suggest that, interestingly, rats exposed to the free-access paradigm were able to self-regulate their alcoholic intake, and indicated that a moderate alcohol consumption was able to induce an increase in behavioural reactivity and an enhancement in spatial learning flexibility. Copyright © 2011 Elsevier B.V. All rights reserved.

Behaviour of Arctic charr Salvelinus alpinus during an induced mating season in captivity: how male relative size influences male behavioural investment and female preference over time.

PubMed

Bolgan, M; O'Brien, J; Picciulin, M; Manning, L; Gammell, M

2017-04-01

The behaviour of sexually mature Arctic charr Salvelinus alpinus specimens (fifth farm generation) was observed in captivity for four consecutive days. Only agonistic interactions between males of different size were facilitated on the first 2 days, while both agonistic and courtship interactions were possible from the third day up to the end of the experiment. The reliability of behavioural analysis was assessed in order to reduce the possibility of observer errors within the generated datasets. The behavioural investment of big males, small males and females was analysed using general linear models (two-way repeated measures ANOVAs with time and male size as factors). A peak in the agonistic interactions between males occurred during the first day of interactions, where the agonistic investment of big males was significantly higher than that of small males. This resulted in an increased investment in submissive behaviour by the small males, who consistently performed submissive behaviours from the second day of interactions up to the end of the trial. Big males were found to invest significantly more than small males in courtship behaviours for the duration of the trial. Even though females performed inter-sexual behaviours towards both big and small males for the entire observation period, female interaction rate towards big males was higher than towards small males. This study suggests that both male investment in mating behaviour and female preference might be related to male characteristics such as body length and that S. alpinus behavioural patterns and mate choice cues might be strongly context-related and characterized by high levels of behavioural plasticity (i.e. presence-absence of certain behavioural units or potential reversal of a mate choice cue) within the same species. Finally, in light of this, some conservation measures are discussed. In particular, effective management plans should take into account the high level of behavioural plasticity likely to be occurring in this species. © 2016 The Fisheries Society of the British Isles.

Simulating Complex, Cold-region Process Interactions Using a Multi-scale, Variable-complexity Hydrological Model

NASA Astrophysics Data System (ADS)

Marsh, C.; Pomeroy, J. W.; Wheater, H. S.

2017-12-01

Accurate management of water resources is necessary for social, economic, and environmental sustainability worldwide. In locations with seasonal snowcovers, the accurate prediction of these water resources is further complicated due to frozen soils, solid-phase precipitation, blowing snow transport, and snowcover-vegetation-atmosphere interactions. Complex process interactions and feedbacks are a key feature of hydrological systems and may result in emergent phenomena, i.e., the arising of novel and unexpected properties within a complex system. One example is the feedback associated with blowing snow redistribution, which can lead to drifts that cause locally-increased soil moisture, thus increasing plant growth that in turn subsequently impacts snow redistribution, creating larger drifts. Attempting to simulate these emergent behaviours is a significant challenge, however, and there is concern that process conceptualizations within current models are too incomplete to represent the needed interactions. An improved understanding of the role of emergence in hydrological systems often requires high resolution distributed numerical hydrological models that incorporate the relevant process dynamics. The Canadian Hydrological Model (CHM) provides a novel tool for examining cold region hydrological systems. Key features include efficient terrain representation, allowing simulations at various spatial scales, reduced computational overhead, and a modular process representation allowing for an alternative-hypothesis framework. Using both physics-based and conceptual process representations sourced from long term process studies and the current cold regions literature allows for comparison of process representations and importantly, their ability to produce emergent behaviours. Examining the system in a holistic, process-based manner can hopefully derive important insights and aid in development of improved process representations.

Attempting to physically explain space-time correlation of extremes

NASA Astrophysics Data System (ADS)

Bernardara, Pietro; Gailhard, Joel

2010-05-01

Spatial and temporal clustering of hydro-meteorological extreme events is scientific evidence. Moreover, the statistical parameters characterizing their local frequencies of occurrence show clear spatial patterns. Thus, in order to robustly assess the hydro-meteorological hazard, statistical models need to be able to take into account spatial and temporal dependencies. Statistical models considering long term correlation for quantifying and qualifying temporal and spatial dependencies are available, such as multifractal approach. Furthermore, the development of regional frequency analysis techniques allows estimating the frequency of occurrence of extreme events taking into account spatial patterns on the extreme quantiles behaviour. However, in order to understand the origin of spatio-temporal clustering, an attempt to find physical explanation should be done. Here, some statistical evidences of spatio-temporal correlation and spatial patterns of extreme behaviour are given on a large database of more than 400 rainfall and discharge series in France. In particular, the spatial distribution of multifractal and Generalized Pareto distribution parameters shows evident correlation patterns in the behaviour of frequency of occurrence of extremes. It is then shown that the identification of atmospheric circulation pattern (weather types) can physically explain the temporal clustering of extreme rainfall events (seasonality) and the spatial pattern of the frequency of occurrence. Moreover, coupling this information with the hydrological modelization of a watershed (as in the Schadex approach) an explanation of spatio-temporal distribution of extreme discharge can also be provided. We finally show that a hydro-meteorological approach (as the Schadex approach) can explain and take into account space and time dependencies of hydro-meteorological extreme events.

The Spatial Behaviour of Animals and Men

ERIC Educational Resources Information Center

Brindley, T. S.

1973-01-01

Describes some common patterns of animal spatial behavior, and discusses spatial relationships that can be observed as an important component of human social behavior. Reports the results of a study relating to the interpersonal distances of people in bus queues in Britain. (JR)

A new bio-inspired optimisation algorithm: Bird Swarm Algorithm

NASA Astrophysics Data System (ADS)

Meng, Xian-Bing; Gao, X. Z.; Lu, Lihua; Liu, Yu; Zhang, Hengzhen

2016-07-01

A new bio-inspired algorithm, namely Bird Swarm Algorithm (BSA), is proposed for solving optimisation applications. BSA is based on the swarm intelligence extracted from the social behaviours and social interactions in bird swarms. Birds mainly have three kinds of behaviours: foraging behaviour, vigilance behaviour and flight behaviour. Birds may forage for food and escape from the predators by the social interactions to obtain a high chance of survival. By modelling these social behaviours, social interactions and the related swarm intelligence, four search strategies associated with five simplified rules are formulated in BSA. Simulations and comparisons based on eighteen benchmark problems demonstrate the effectiveness, superiority and stability of BSA. Some proposals for future research about BSA are also discussed.

Prolonged secretion of cortisol as a possible mechanism underlying stress and depressive behaviour

PubMed Central

Qin, Dong-dong; Rizak, Joshua; Feng, Xiao-li; Yang, Shang-chuan; Lü, Long-bao; Pan, Lei; Yin, Yong; Hu, Xin-tian

2016-01-01

Stress is associated with the onset of depressive episodes, and cortisol hypersecretion is considered a biological risk factor of depression. However, the possible mechanisms underlying stress, cortisol and depressive behaviours are inconsistent in the literature. This study examined the interrelationships among stress, cortisol and observed depressive behaviours in female rhesus macaques for the first time and explored the possible mechanism underlying stress and depressive behaviour. Female monkeys were video-recorded, and the frequencies of life events and the duration of huddling were analysed to measure stress and depressive behaviour. Hair samples were used to measure chronic cortisol levels, and the interactions between stress and cortisol in the development of depressive behaviour were further evaluated. Significant correlations were found between stress and depressive behaviour measures and between cortisol levels and depressive behaviour. Stress was positively correlated with cortisol levels, and these two factors interacted with each other to predict the monkeys’ depressive behaviours. This finding extends the current understanding of stress/cortisol interactions in depression, especially pertaining to females. PMID:27443987

Social environment as a factor affecting exploration and learning in pre-juvenile rats.

PubMed

Modlinska, Klaudia; Stryjek, Rafał; Chrzanowska, Anna; Pisula, Wojciech

2018-08-01

Stress associated with social isolation in early life can lead to disturbances in the emotional regulation in adult rats. However, there are no reports on the impact of isolation from the mother while providing contact with peers. Under such conditions, young individuals have the opportunity to interact with others, are able to develop social behaviour, etc. Yet, there is no stimulation and care provided by the mother. We examined the relative impact of maternal contact and sibling contact in the rarely studied pre-juvenile (3rd and 4th week post birth) period on subsequent development. An experiment was designed to compare the impact of different social environments on the animals' behaviour in adulthood. There were three breeding conditions: young with mother, young with peers, and standard breeding conditions. Adult rats were subjected to a T-Maze test to measure the level of exploratory behaviour. Spatial learning was assessed by placing water bottles in the side corridors. The analysis revealed that a distorted environment during the development process has a negative impact on the rats' emotional regulation and a subtle effect on related aspects of adaptive behaviours (i.e. exploration). In the pre-juvenile period, to some degree, contact with peers may be complementary to the mother's influence. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Cooperation in microbial communities and their biotechnological applications

PubMed Central

Cavaliere, Matteo; Feng, Song; Soyer, Orkun S.

2017-01-01

Summary Microbial communities are increasingly utilized in biotechnology. Efficiency and productivity in many of these applications depends on the presence of cooperative interactions between members of the community. Two key processes underlying these interactions are the production of public goods and metabolic cross‐feeding, which can be understood in the general framework of ecological and evolutionary (eco‐evo) dynamics. In this review, we illustrate the relevance of cooperative interactions in microbial biotechnological processes, discuss their mechanistic origins and analyse their evolutionary resilience. Cooperative behaviours can be damaged by the emergence of ‘cheating’ cells that benefit from the cooperative interactions but do not contribute to them. Despite this, cooperative interactions can be stabilized by spatial segregation, by the presence of feedbacks between the evolutionary dynamics and the ecology of the community, by the role of regulatory systems coupled to the environmental conditions and by the action of horizontal gene transfer. Cooperative interactions enrich microbial communities with a higher degree of robustness against environmental stress and can facilitate the evolution of more complex traits. Therefore, the evolutionary resilience of microbial communities and their ability to constraint detrimental mutants should be considered to design robust biotechnological applications. PMID:28447371

The scaling features of the 3D organization of chromosomes are highlighted by a transformation à la Kadanoff of Hi-C data

NASA Astrophysics Data System (ADS)

Chiariello, Andrea M.; Bianco, Simona; Annunziatella, Carlo; Esposito, Andrea; Nicodemi, Mario

2017-11-01

Technologies such as Hi-C and GAM have revealed that chromosomes are not randomly folded into the nucleus of cells, but are composed by a sequence of contact domains (TADs), each typically 0.5 Mb long. However, the larger scale organization of the genome remains still not well understood. To investigate the scaling behaviour of chromosome folding, here we apply an approach à la Kadanoff, inspired by the Renormalization Group theory, to Hi-C interaction data, across different cell types and chromosomes. We find that the genome is characterized by complex scaling features, where the average size of contact domains exhibits a power-law behaviour with the rescaling level. That is compatible with the existence of contact domains extending across length scales up to chromosomal sizes. The scaling exponent is statistically indistinguishable among the different murine cell types analysed. These results point toward a scenario of a universal higher-order spatial architecture of the genome, which could reflect fundamental, organizational principles.

A global perspective on the trophic geography of sharks.

PubMed

Bird, Christopher S; Veríssimo, Ana; Magozzi, Sarah; Abrantes, Kátya G; Aguilar, Alex; Al-Reasi, Hassan; Barnett, Adam; Bethea, Dana M; Biais, Gérard; Borrell, Asuncion; Bouchoucha, Marc; Boyle, Mariah; Brooks, Edward J; Brunnschweiler, Juerg; Bustamante, Paco; Carlisle, Aaron; Catarino, Diana; Caut, Stéphane; Cherel, Yves; Chouvelon, Tiphaine; Churchill, Diana; Ciancio, Javier; Claes, Julien; Colaço, Ana; Courtney, Dean L; Cresson, Pierre; Daly, Ryan; de Necker, Leigh; Endo, Tetsuya; Figueiredo, Ivone; Frisch, Ashley J; Hansen, Joan Holst; Heithaus, Michael; Hussey, Nigel E; Iitembu, Johannes; Juanes, Francis; Kinney, Michael J; Kiszka, Jeremy J; Klarian, Sebastian A; Kopp, Dorothée; Leaf, Robert; Li, Yunkai; Lorrain, Anne; Madigan, Daniel J; Maljković, Aleksandra; Malpica-Cruz, Luis; Matich, Philip; Meekan, Mark G; Ménard, Frédéric; Menezes, Gui M; Munroe, Samantha E M; Newman, Michael C; Papastamatiou, Yannis P; Pethybridge, Heidi; Plumlee, Jeffrey D; Polo-Silva, Carlos; Quaeck-Davies, Katie; Raoult, Vincent; Reum, Jonathan; Torres-Rojas, Yassir Eden; Shiffman, David S; Shipley, Oliver N; Speed, Conrad W; Staudinger, Michelle D; Teffer, Amy K; Tilley, Alexander; Valls, Maria; Vaudo, Jeremy J; Wai, Tak-Cheung; Wells, R J David; Wyatt, Alex S J; Yool, Andrew; Trueman, Clive N

2018-02-01

Sharks are a diverse group of mobile predators that forage across varied spatial scales and have the potential to influence food web dynamics. The ecological consequences of recent declines in shark biomass may extend across broader geographic ranges if shark taxa display common behavioural traits. By tracking the original site of photosynthetic fixation of carbon atoms that were ultimately assimilated into muscle tissues of 5,394 sharks from 114 species, we identify globally consistent biogeographic traits in trophic interactions between sharks found in different habitats. We show that populations of shelf-dwelling sharks derive a substantial proportion of their carbon from regional pelagic sources, but contain individuals that forage within additional isotopically diverse local food webs, such as those supported by terrestrial plant sources, benthic production and macrophytes. In contrast, oceanic sharks seem to use carbon derived from between 30° and 50° of latitude. Global-scale compilations of stable isotope data combined with biogeochemical modelling generate hypotheses regarding animal behaviours that can be tested with other methodological approaches.

Persistence and long-term memories of daily maximum and minimum temperatures in southern South America

NASA Astrophysics Data System (ADS)

Naumann, Gustavo; Vargas, Walter M.; Minetti, Juan L.

2011-10-01

The persistence and long-term memories in daily maximum and minimum temperature series during the instrumental period in southern South America were analysed. Here, we found a markedly seasonal pattern both for short- and long-term memories that can lead to enhanced predictability on intraseasonal timescales. In addition, well-defined spatial patterns of these properties were found in the region. Throughout the entire region, the strongest dependence was observed in autumn and early winter. In the Patagonia region only, the temperatures exhibited more memory during the spring. In general, these elements indicate that nonlinear interactions exist between the annual cycles of temperature and its anomalies. Knowledge of the spatiotemporal behaviour of these long-term memories can be used in the building of stochastic models that only use persistence. It is possible to propose two objective forecast models based on linear interactions associated with persistence and one that allows for the use of information from nonlinear interactions that are manifested in the form of forerunners.

Sex and boldness explain individual differences in spatial learning in a lizard.

PubMed

Carazo, Pau; Noble, Daniel W A; Chandrasoma, Dani; Whiting, Martin J

2014-05-07

Understanding individual differences in cognitive performance is a major challenge to animal behaviour and cognition studies. We used the Eastern water skink (Eulamprus quoyii) to examine associations between exploration, boldness and individual variability in spatial learning, a dimension of lizard cognition with important bearing on fitness. We show that males perform better than females in a biologically relevant spatial learning task. This is the first evidence for sex differences in learning in a reptile, and we argue that it is probably owing to sex-specific selective pressures that may be widespread in lizards. Across the sexes, we found a clear association between boldness after a simulated predatory attack and the probability of learning the spatial task. In contrast to previous studies, we found a nonlinear association between boldness and learning: both 'bold' and 'shy' behavioural types were more successful learners than intermediate males. Our results do not fit with recent predictions suggesting that individual differences in learning may be linked with behavioural types via high-low-risk/reward trade-offs. We suggest the possibility that differences in spatial cognitive performance may arise in lizards as a consequence of the distinct environmental variability and complexity experienced by individuals as a result of their sex and social tactics.

Using ecology to guide the study of cognitive and neural mechanisms of different aspects of spatial memory in food-hoarding animals.

PubMed

Smulders, Tom V; Gould, Kristy L; Leaver, Lisa A

2010-03-27

Understanding the survival value of behaviour does not tell us how the mechanisms that control this behaviour work. Nevertheless, understanding survival value can guide the study of these mechanisms. In this paper, we apply this principle to understanding the cognitive mechanisms that support cache retrieval in scatter-hoarding animals. We believe it is too simplistic to predict that all scatter-hoarding animals will outperform non-hoarding animals on all tests of spatial memory. Instead, we argue that we should look at the detailed ecology and natural history of each species. This understanding of natural history then allows us to make predictions about which aspects of spatial memory should be better in which species. We use the natural hoarding behaviour of the three best-studied groups of scatter-hoarding animals to make predictions about three aspects of their spatial memory: duration, capacity and spatial resolution, and we test these predictions against the existing literature. Having laid out how ecology and natural history can be used to predict detailed cognitive abilities, we then suggest using this approach to guide the study of the neural basis of these abilities. We believe that this complementary approach will reveal aspects of memory processing that would otherwise be difficult to discover.

Children with PIMD in interaction with peers with PIMD or siblings.

PubMed

Nijs, S; Vlaskamp, C; Maes, B

2016-01-01

The complex disabilities of children with profound intellectual and multiple disabilities (PIMD) impede their presentation of peer directed behaviours. Interactions with typically developing peers have been observed to be more frequent than those with peers with PIMD. The typically developing peers with whom people with PIMD have frequent contact are their siblings. In this study, the amount of peer directed behaviours was compared between an interaction with a sibling and an interaction with a peer with PIMD. In addition, the attention directing strategies of the siblings, and how these affect the presentation of peer directed behaviours, were examined. Thirteen children and young people with PIMD, who had a typically developing sibling, were identified. For each of these thirteen children, a peer with PIMD and a sibling were selected. The child with PIMD was observed together with a peer with PIMD and together with a sibling. In both conditions, video observations were conducted. A coding scheme for the peer directed behaviours of the children and young people with PIMD and a coding scheme for the attention directing behaviours of the siblings were used. Descriptive, comparative and sequential analyses were conducted. Significantly, more peer directed behaviours of the children with PIMD were observed in the condition with the sibling (30.76%) compared with that of the condition with the peer with PIMD (13.73%). The siblings presented attention directing behaviours in 30% of the time; the most frequently used was nonverbal behaviour. When the siblings presented a combination of verbal and nonverbal attention directing behaviours, they elicited multiple peer directed behaviours in the children and young people with PIMD. Persons with PIMD interact more with their siblings compared with their peers with PIMD. Interacting with siblings may probably be more motivating and encouraging. Presenting a combination of verbal and nonverbal behaviours attracts more attention of the persons with PIMD. © 2015 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

Quantifying dynamic rheology, phase interactions and strain localisation in deforming three phase magmas using high-speed x-ray tomography

NASA Astrophysics Data System (ADS)

Dobson, Katherine; Pistone, Mattia; Fife, Julie; Cordonnier, Benoit; Blundy, Jon; Dingwell, Don; Lee, Peter

2015-04-01

The crystal and bubble cargoes of magmas are critical to controlling magma mobility and rheology. These cargos vary in both time and space and the local, and bulk, rheological behaviour are correspondingly heterogeneous. Tracking how these heterogeneous cargoes evolve, and how crystals and bubbles interact with each other in deforming systems is a critical challenge in volcanology, as these processes control both the chemical and physical evolution of the magma, including phenomena such as melt-crystal segregation, strain localisation, and fragmentation. The only methodology available to track these processes in real time, and at the scale of individual melt-crystal-bubble interactions is high speed x-ray tomography. This non-destructive imaging technique allows the rapid acquisition of sequential 3D images that capture the physical, and to some degree chemical, microstructure of the sample during a deformation cycle. We utilise in situ tomographic methods developed in materials science to perfume magmatic deformation experiments on synthesized three phase systems at magmatic temperatures. Through a novel combination of a high temperature laser heating system [1] in situ micro-precision deformation apparatus [2] and the temporal and spatial resolution available at the TOMCAT beam line at the Swiss Light Source synchrotron facility we performed in situ observations of the microstructural evolution of a synthesized anhydrous borosilicate melt seeded with a variable concentration of non-reactive rutile crystals and air bubbles (30-70 volume %). The experiments were conducted at 800-1000C, under constant deformation rates of 0.25-5.00 microns/second. Each 3D image has 2D and 3D spatial resolution of approximately 3 microns per pixel, and each 3D image took ~3 seconds to acquire. Here we present this innovative high speed, high temperature, syn-deformation tomographic data , and show how it can be used to trace the location and local distribution of each crystal and bubble within a small volume cylindrical experimental charge (3mm diameter, 5mm length) undergoing shear along a single vertical plane. By qualitative and quantitative analysis of the sequential images collected over 5-15 minute deformation cycles we track the local bubble, crystal and melt concentrations on a range of spatial scales. From this we calculate a spatially heterogeneous and dynamic local viscosity [3] and assess our results against recently developed 3-phase rheological models [4]. We will present how this real time 4D information can be used to quantify the dynamics of magma motion, discuss the implications of spatially and temporally variable rheological behaviours, and show how this novel technique can be integrated with other volcanology methods to improve our understanding of volcanic and magmatic processes. [1] Fife et al. 2012. J. Synchrotron Rad. 19, 352-358 [2] Kareh et al. 2014 Nature Comm. 5 4464. [3] Giordano, et al. 2008 EPSL 271 123-134. [4] Truby et al. 2015 P.Roy.Soc.A. 2015471 20140557

Sex differences on the competitive place task in the water maze: The influence of peripheral pool time on spatial navigation performance in rats.

PubMed

Devan, Bryan D; Tobin, Elizabeth L; Dunn, Emily N; Magalis, Christopher

2016-11-01

This study investigated sex differences on the competitive place version of the Morris water maze task to determine whether potential strategy differences would emerge during any phase of the study but in particular on the competitive place phase. Previous findings indicate that this version of the task is highly sensitive to measures that disrupt NMDA-dependent synaptic plasticity within the hippocampus during memory consolidation (McDonald et al., 2005). The present findings revealed significant sex differences during all phases of the study, including Phase I with standard place training to located a hidden platform/goal, Phase II mass training to a new place with the platform/goal relocated to the diagonally opposite quadrant and Phase III, competitive place probe test with the platform removed to measure spatial behaviour directed at either location. The findings showed no sex difference in escape latency and other standard performance measures during the first two phases, initial place acquisition and mass training to a new location. A very subtle male advantage in visiting both Old and New place locations during the third phase place competition test was observed, however, in the time spent swimming in the periphery of the pool, the pool wall (Zone C - outer third radial distance) was increased for females during all phases of the study, suggesting a general effect may have influenced place location search behaviour of the females. Increased peripheral pool time may represent a female preference for approaching the wall, a local cue. Alternatively, the possibility that increased peripheral swimming/thigmotaxis may represent hormonal influences interacting with strategic preferences were discussed, though no definitive conclusions about sex differences in cognitive-spatial performance or memory consolidation were inferred from the present findings. The findings suggest that mixed results reported in the literature by others may be due in part to an interaction with a persistent peripheral pool swimming response demonstrated in female rats. Copyright © 2016 Elsevier B.V. All rights reserved.

Controlled Study of the Impact on Child Behaviour Problems of Intensive Interaction for Children with ASD

ERIC Educational Resources Information Center

Tee, Abi; Reed, Phil

2017-01-01

Pupils with autism spectrum disorder (ASD) received 6 months of intensive interaction or treatment as usual. They were assessed for behaviour problems at the start and end of the period, and changes were related to child and parent factors. Intensive interaction did not offer any greater advantages to child behaviour than treatment as usual.…

What are you or who are you? The emergence of social interaction between dog and an unidentified moving object (UMO).

PubMed

Gergely, Anna; Petró, Eszter; Topál, József; Miklósi, Ádám

2013-01-01

Robots offer new possibilities for investigating animal social behaviour. This method enhances controllability and reproducibility of experimental techniques, and it allows also the experimental separation of the effects of bodily appearance (embodiment) and behaviour. In the present study we examined dogs' interactive behaviour in a problem solving task (in which the dog has no access to the food) with three different social partners, two of which were robots and the third a human behaving in a robot-like manner. The Mechanical UMO (Unidentified Moving Object) and the Mechanical Human differed only in their embodiment, but showed similar behaviour toward the dog. In contrast, the Social UMO was interactive, showed contingent responsiveness and goal-directed behaviour and moved along varied routes. The dogs showed shorter looking and touching duration, but increased gaze alternation toward the Mechanical Human than to the Mechanical UMO. This suggests that dogs' interactive behaviour may have been affected by previous experience with typical humans. We found that dogs also looked longer and showed more gaze alternations between the food and the Social UMO compared to the Mechanical UMO. These results suggest that dogs form expectations about an unfamiliar moving object within a short period of time and they recognise some social aspects of UMOs' behaviour. This is the first evidence that interactive behaviour of a robot is important for evoking dogs' social responsiveness.

Importance of fish behaviour in modelling conservation problems: food limitation as an example

Treesearch

Steven Railsback; Bret Harvey

2011-01-01

Simulation experiments using the inSTREAM individual-based brown trout Salmo trutta population model explored the role of individual adaptive behaviour in food limitation, as an example of how behaviour can affect managers’ understanding of conservation problems. The model includes many natural complexities in habitat (spatial and temporal variation in characteristics...

Early Learning and Adaptive Behaviour in Toddlers with Down Syndrome: Evidence for an Emerging Behavioural Phenotype?

ERIC Educational Resources Information Center

Fidler, Deborah; Hepburn, Susan; Rogers, Sally

2006-01-01

Background: Though the Down syndrome behavioural phenotype has been described as involving relative strengths in visuo-spatial processing and sociability, and relative weaknesses in verbal skills and motor planning, the early emergence of this phenotypic pattern of strengths and weaknesses has not yet been fully explored. Method: In this study, we…

Children with Praderwilli Syndrome Vs. Williams Syndrome: Indirect Effects on Parents during a Jigsaw Puzzle Task

ERIC Educational Resources Information Center

Ly, T. M.; Hodapp, R. M.

2005-01-01

Background: Genetic disorders predispose individuals to exhibit characteristic behaviours, which in turn elicit particular behaviours from others. In response to the strength of Prader?Willi syndrome (PWS) and weakness of Williams syndrome (WS) in visual-spatial tasks such as jigsaw puzzles, parents' behaviours can be affected by their child's…

Behavioural inventory of the giraffe (Giraffa camelopardalis).

PubMed

Seeber, Peter A; Ciofolo, Isabelle; Ganswindt, André

2012-11-22

Numerous factors like continuous habitat reduction or fragmentation for free-ranging giraffes (Giraffa camelopardalis) as well as e.g. suboptimal housing conditions for animals in captivity might lead to behavioural alterations as part of the overall adaptation process to the changing living conditions. In order to facilitate current and future studies on giraffe behaviour, a comprehensive ethogram was compiled based on existing literature, as well as observations on giraffes in the wild (Hwange National Park, Zimbabwe; Entabeni Game Reserve, South Africa), and in captivity (National Zoological Gardens of South Africa, Pretoria). The resulting ethogram lists 65 different behavioural patterns, which were described and grouped into seven categories: General activities, Abnormal repetitive behaviours, General interactions, Bull-Cow behaviour, Bull-Bull behaviour, Cow-Bull behaviour, Maternal behaviours, and Interactions by calves. The behaviours were further described regarding a presumed purpose, particularly with respect to social interactions and sexual behaviour. Contradictory descriptions from previous studies were considered and discussed in comparison with our own observations. This ethogram provides a basis for current and future studies by suggesting a terminology which can be used for harmonizing behavioural observations, thus helping to facilitate comparability of future results. Subsequently, a better understanding of the behavioural ecology of giraffes in the wild as well as in captivity could aid future conservation efforts.

Behavioural inventory of the giraffe (Giraffa camelopardalis)

PubMed Central

2012-01-01

Background Numerous factors like continuous habitat reduction or fragmentation for free-ranging giraffes (Giraffa camelopardalis) as well as e.g. suboptimal housing conditions for animals in captivity might lead to behavioural alterations as part of the overall adaptation process to the changing living conditions. In order to facilitate current and future studies on giraffe behaviour, a comprehensive ethogram was compiled based on existing literature, as well as observations on giraffes in the wild (Hwange National Park, Zimbabwe; Entabeni Game Reserve, South Africa), and in captivity (National Zoological Gardens of South Africa, Pretoria). Findings The resulting ethogram lists 65 different behavioural patterns, which were described and grouped into seven categories: General activities, Abnormal repetitive behaviours, General interactions, Bull-Cow behaviour, Bull-Bull behaviour, Cow-Bull behaviour, Maternal behaviours, and Interactions by calves. The behaviours were further described regarding a presumed purpose, particularly with respect to social interactions and sexual behaviour. Contradictory descriptions from previous studies were considered and discussed in comparison with our own observations. Conclusions This ethogram provides a basis for current and future studies by suggesting a terminology which can be used for harmonizing behavioural observations, thus helping to facilitate comparability of future results. Subsequently, a better understanding of the behavioural ecology of giraffes in the wild as well as in captivity could aid future conservation efforts. PMID:23173954

Exercise self-identity: interactions with social comparison and exercise behaviour.

PubMed

Verkooijen, Kirsten T; de Bruijn, Gert-Jan

2013-01-01

Possible interactions among exercise self-identity, social comparison and exercise behaviour were explored in a sample of 417 undergraduate students (mean age = 21.5, SD = 3.0; 73% female). Two models were examined using self-report data; (1) a mediation model which proposed an association between social comparison and exercise behaviour mediated by exercise self-identity and (2) a moderation model proposing an association between exercise behaviour and self-identity moderated by social comparison. Results of the mediation analyses revealed partial mediation of the social comparison--exercise behaviour relationship by self-identity in females. Results of the moderation analyses revealed in males a significant interaction of social comparison with exercise behaviour in the prediction of self-identity - the positive association between exercise behaviour and exercise self-identity showed only significant among male students who believed to exercise equally much or less than peers. Possible explanations and implications for exercise promotion are discussed.

Bisphenol-A exposures and behavioural aberrations: median and linear spline and meta-regression analyses of 12 toxicity studies in rodents.

PubMed

Peluso, Marco E M; Munnia, Armelle; Ceppi, Marcello

2014-11-05

Exposures to bisphenol-A, a weak estrogenic chemical, largely used for the production of plastic containers, can affect the rodent behaviour. Thus, we examined the relationships between bisphenol-A and the anxiety-like behaviour, spatial skills, and aggressiveness, in 12 toxicity studies of rodent offspring from females orally exposed to bisphenol-A, while pregnant and/or lactating, by median and linear splines analyses. Subsequently, the meta-regression analysis was applied to quantify the behavioural changes. U-shaped, inverted U-shaped and J-shaped dose-response curves were found to describe the relationships between bisphenol-A with the behavioural outcomes. The occurrence of anxiogenic-like effects and spatial skill changes displayed U-shaped and inverted U-shaped curves, respectively, providing examples of effects that are observed at low-doses. Conversely, a J-dose-response relationship was observed for aggressiveness. When the proportion of rodents expressing certain traits or the time that they employed to manifest an attitude was analysed, the meta-regression indicated that a borderline significant increment of anxiogenic-like effects was present at low-doses regardless of sexes (β)=-0.8%, 95% C.I. -1.7/0.1, P=0.076, at ≤120 μg bisphenol-A. Whereas, only bisphenol-A-males exhibited a significant inhibition of spatial skills (β)=0.7%, 95% C.I. 0.2/1.2, P=0.004, at ≤100 μg/day. A significant increment of aggressiveness was observed in both the sexes (β)=67.9,C.I. 3.4, 172.5, P=0.038, at >4.0 μg. Then, bisphenol-A treatments significantly abrogated spatial learning and ability in males (P<0.001 vs. females). Overall, our study showed that developmental exposures to low-doses of bisphenol-A, e.g. ≤120 μg/day, were associated to behavioural aberrations in offspring. Copyright © 2014. Published by Elsevier Ireland Ltd.

Network Analysis: A Novel Approach to Understand Suicidal Behaviour

PubMed Central

de Beurs, Derek

2017-01-01

Although suicide is a major public health issue worldwide, we understand little of the onset and development of suicidal behaviour. Suicidal behaviour is argued to be the end result of the complex interaction between psychological, social and biological factors. Epidemiological studies resulted in a range of risk factors for suicidal behaviour, but we do not yet understand how their interaction increases the risk for suicidal behaviour. A new approach called network analysis can help us better understand this process as it allows us to visualize and quantify the complex association between many different symptoms or risk factors. A network analysis of data containing information on suicidal patients can help us understand how risk factors interact and how their interaction is related to suicidal thoughts and behaviour. A network perspective has been successfully applied to the field of depression and psychosis, but not yet to the field of suicidology. In this theoretical article, I will introduce the concept of network analysis to the field of suicide prevention, and offer directions for future applications and studies.

Toxoplasma gondii strain-dependent effects on mouse behaviour.

PubMed

Kannan, Geetha; Moldovan, Krisztina; Xiao, Jian-Chun; Yolken, Robert H; Jones-Brando, Lorraine; Pletnikov, Mikhail V

2010-06-01

Toxoplasma gondii reportedly manipulates rodent behaviour to increase transmission to its definitive feline host. We compared the effects of mouse infection by two Type II strains of T. gondii, Prugniaud (PRU) and ME49, on attraction to cat odour, locomotor activity, anxiety, sensorimotor gating, and spatial working and recognition memory 2 months post-infection (mpi). Attraction to cat odour was reassessed 7 mpi. At 2 mpi, mice infected with either strain exhibited significantly more attraction to cat odour than uninfected animals did, but only PRU-infected mice exhibited this behaviour 7 mpi. PRU-infected mice had significantly greater body weights and hyperactivity, while ME49-infected mice exhibited impaired spatial working memory. No differences in parasite antibody titres were seen between PRU- and ME49-infected mice. The present data suggest the effect of T. gondii infection on mouse behaviour is parasite strain-dependent.

The role of pregnenolone sulphate in spatial orientation-acquisition and retention: an interplay between cognitive potentiation and mood regulation.

PubMed

Plescia, Fulvio; Marino, Rosa A M; Cannizzaro, Emanuele; Brancato, Anna; Cannizzaro, Carla

2013-10-01

Neurosteroids can alter neuronal excitability interacting with specific neurotransmitter receptors, thus affecting several functions such as cognition and emotionality. In this study, we investigated, in adult male rats, the effects of the acute administration of pregnenolone-sulfate (PREGS) (10 mg/Kg, s.c.) on cognitive processes using the Can test, a non aversive spatial/visual task which allows the assessment of spatial information-acquisition during the baseline training, and of memory retention in the longitudinal study. Furthermore, on the basis of PREGS pharmacological profile, the modulation of depressive-like behaviour was also evaluated in the forced swim test (FST). Our results indicate that acute PREGS induces: an improvement in spatial orientation-acquisition and in reference memory, during the baseline training; a strengthening effect on reference and working memory during the longitudinal study. A decrease in immobility time in the FST has also been recorded. In conclusion, PREGS exerts enhancing properties on acquisition, consolidation and retrieval of spatial information, probably due of improved hippocampal-dependent memory processes. The additional antidepressant effect observed in the FST can provide further evidence in support of the potential of PREGS as a therapeutic tool for the treatment of cognitive deficits associated with mood disorders. This article is part of a Special Issue entitled: insert SI title. Copyright © 2013 Elsevier B.V. All rights reserved.

Mean field analysis of a spatial stochastic model of a gene regulatory network.

PubMed

Sturrock, M; Murray, P J; Matzavinos, A; Chaplain, M A J

2015-10-01

A gene regulatory network may be defined as a collection of DNA segments which interact with each other indirectly through their RNA and protein products. Such a network is said to contain a negative feedback loop if its products inhibit gene transcription, and a positive feedback loop if a gene product promotes its own production. Negative feedback loops can create oscillations in mRNA and protein levels while positive feedback loops are primarily responsible for signal amplification. It is often the case in real biological systems that both negative and positive feedback loops operate in parameter regimes that result in low copy numbers of gene products. In this paper we investigate the spatio-temporal dynamics of a single feedback loop in a eukaryotic cell. We first develop a simplified spatial stochastic model of a canonical feedback system (either positive or negative). Using a Gillespie's algorithm, we compute sample trajectories and analyse their corresponding statistics. We then derive a system of equations that describe the spatio-temporal evolution of the stochastic means. Subsequently, we examine the spatially homogeneous case and compare the results of numerical simulations with the spatially explicit case. Finally, using a combination of steady-state analysis and data clustering techniques, we explore model behaviour across a subregion of the parameter space that is difficult to access experimentally and compare the parameter landscape of our spatio-temporal and spatially-homogeneous models.

Towards evenly distributed grazing patterns: including social context in sheep management strategies

PubMed Central

Morales, Juan Manuel

2016-01-01

Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals’ foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals’ space use patterns, our aim was to explore the potential effects of including animals’ social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock) grazing on three different paddocks (with sizes from 80 to 1000 Ha) during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets), age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females) used more intensively the most preferred areas and low-ranked (i.e., yearlings) used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour). Discussion. Although homogenization and segregation of flocks by classes are common practices to increase flock productivity, we are proposing an alternative that employs behavioural interactions in heterogeneous flocks to generate more evenly distributed grazing patterns. This practice can be combined with other practices such as rotational grazing and guardian dogs (to decrease mortality levels that may be generated by sheep grazing on more risky habitats). This does not imply any modifications of livestock stocking rates and densities or any additional investments for labour and materials. Considering livestock behaviour is critical for the design of sustainable management practices that balance landscape conservation and livestock productivity. PMID:27366650

Population genetics of sporophytic self-incompatibility in Senecio squalidus L. (Asteraceae) II: a spatial autocorrelation approach to determining mating behaviour in the presence of low S allele diversity.

PubMed

Brennan, A C; Harris, S A; Hiscock, S J

2003-11-01

We recently estimated that as few as six S alleles represent the extent of S locus diversity in a British population of the self-incompatible (SI) coloniser Senecio squalidus (Oxford Ragwort). Despite the predicted constraints to mating imposed by such a low number of S alleles, S. squalidus maintains a strong sporophytic self-incompatibility (SSI) system and there is no evidence for a breakdown of SSI or any obvious negative reproductive consequences for this highly successful coloniser. The present paper assesses mating behaviour in an Oxford S. squalidus population through observations of its effect on spatial patterns of genetic diversity and thus the extent to which it is responsible for ameliorating the potentially detrimental reproductive consequences of low S allele diversity in British S. squalidus. A spatial autocorrelation (SA) treatment of S locus and allozyme polymorphism data for four loci indicates that mating events regularly occur at all the distance classes examined from 60 to 480 m throughout the entire sample population. Less SA is observed for S locus data than for allozyme data in accordance with the hypothesis that SSI and low diversity at the S locus are driving these large-scale mating events. The limited population structure at small distances of 60 m and less observed for SA analysis of the Me-2 locus and by F-statistics for all the allozyme data, is evidence of some local relatedness due to limited seed and pollen dispersal in S. squalidus. However, the overall impression of mating dynamics in this S. squalidus population is that of ample potential mating opportunities with many individuals at large population scales, indicating that reproductive success is not seriously affected by few S alleles available for mating interactions.

Assessing implicit odor localization in humans using a cross-modal spatial cueing paradigm.

PubMed

Moessnang, Carolin; Finkelmeyer, Andreas; Vossen, Alexandra; Schneider, Frank; Habel, Ute

2011-01-01

Navigation based on chemosensory information is one of the most important skills in the animal kingdom. Studies on odor localization suggest that humans have lost this ability. However, the experimental approaches used so far were limited to explicit judgements, which might ignore a residual ability for directional smelling on an implicit level without conscious appraisal. A novel cueing paradigm was developed in order to determine whether an implicit ability for directional smelling exists. Participants performed a visual two-alternative forced choice task in which the target was preceded either by a side-congruent or a side-incongruent olfactory spatial cue. An explicit odor localization task was implemented in a second experiment. No effect of cue congruency on mean reaction times could be found. However, a time by condition interaction emerged, with significantly slower responses to congruently compared to incongruently cued targets at the beginning of the experiment. This cueing effect gradually disappeared throughout the course of the experiment. In addition, participants performed at chance level in the explicit odor localization task, thus confirming the results of previous research. The implicit cueing task suggests the existence of spatial information processing in the olfactory system. Response slowing after a side-congruent olfactory cue is interpreted as a cross-modal attentional interference effect. In addition, habituation might have led to a gradual disappearance of the cueing effect. It is concluded that under immobile conditions with passive monorhinal stimulation, humans are unable to explicitly determine the location of a pure odorant. Implicitly, however, odor localization seems to exert an influence on human behaviour. To our knowledge, these data are the first to show implicit effects of odor localization on overt human behaviour and thus support the hypothesis of residual directional smelling in humans. © 2011 Moessnang et al.

The impact of mating systems and dispersal on fine-scale genetic structure at maternally, paternally and biparentally inherited markers.

PubMed

Shaw, Robyn E; Banks, Sam C; Peakall, Rod

2018-01-01

For decades, studies have focused on how dispersal and mating systems influence genetic structure across populations or social groups. However, we still lack a thorough understanding of how these processes and their interaction shape spatial genetic patterns over a finer scale (tens-hundreds of metres). Using uniparentally inherited markers may help answer these questions, yet their potential has not been fully explored. Here, we use individual-level simulations to investigate the effects of dispersal and mating system on fine-scale genetic structure at autosomal, mitochondrial and Y chromosome markers. Using genetic spatial autocorrelation analysis, we found that dispersal was the major driver of fine-scale genetic structure across maternally, paternally and biparentally inherited markers. However, when dispersal was restricted (mean distance = 100 m), variation in mating behaviour created strong differences in the comparative level of structure detected at maternally and paternally inherited markers. Promiscuity reduced spatial genetic structure at Y chromosome loci (relative to monogamy), whereas structure increased under polygyny. In contrast, mitochondrial and autosomal markers were robust to differences in the specific mating system, although genetic structure increased across all markers when reproductive success was skewed towards fewer individuals. Comparing males and females at Y chromosome vs. mitochondrial markers, respectively, revealed that some mating systems can generate similar patterns to those expected under sex-biased dispersal. This demonstrates the need for caution when inferring ecological and behavioural processes from genetic results. Comparing patterns between the sexes, across a range of marker types, may help us tease apart the processes shaping fine-scale genetic structure. © 2017 John Wiley & Sons Ltd.

Seeing music: The perception of melodic 'ups and downs' modulates the spatial processing of visual stimuli.

PubMed

Romero-Rivas, Carlos; Vera-Constán, Fátima; Rodríguez-Cuadrado, Sara; Puigcerver, Laura; Fernández-Prieto, Irune; Navarra, Jordi

2018-05-10

Musical melodies have "peaks" and "valleys". Although the vertical component of pitch and music is well-known, the mechanisms underlying its mental representation still remain elusive. We show evidence regarding the importance of previous experience with melodies for crossmodal interactions to emerge. The impact of these crossmodal interactions on other perceptual and attentional processes was also studied. Melodies including two tones with different frequency (e.g., E4 and D3) were repeatedly presented during the study. These melodies could either generate strong predictions (e.g., E4-D3-E4-D3-E4-[D3]) or not (e.g., E4-D3-E4-E4-D3-[?]). After the presentation of each melody, the participants had to judge the colour of a visual stimulus that appeared in a position that was, according to the traditional vertical connotations of pitch, either congruent (e.g., high-low-high-low-[up]), incongruent (high-low-high-low-[down]) or unpredicted with respect to the melody. Behavioural and electroencephalographic responses to the visual stimuli were obtained. Congruent visual stimuli elicited faster responses at the end of the experiment than at the beginning. Additionally, incongruent visual stimuli that broke the spatial prediction generated by the melody elicited larger P3b amplitudes (reflecting 'surprise' responses). Our results suggest that the passive (but repeated) exposure to melodies elicits spatial predictions that modulate the processing of other sensory events. Copyright © 2018 Elsevier Ltd. All rights reserved.

Identifying Successful Learners from Interaction Behaviour

ERIC Educational Resources Information Center

McCuaig, Judi; Baldwin, Julia

2012-01-01

The interaction behaviours of successful, high-achieving learners when using a Learning Management System (LMS) are different than the behaviours of learners who are having more difficulty mastering the course material. This paper explores the idea that conventional Learning Management Systems can exploit data mining techniques to predict the…

The Impact of the Brain-Derived Neurotrophic Factor Gene on Trauma and Spatial Processing.

PubMed

Miller, Jessica K; McDougall, Siné; Thomas, Sarah; Wiener, Jan

2017-11-27

The influence of genes and the environment on the development of Post-Traumatic Stress Disorder (PTSD) continues to motivate neuropsychological research, with one consistent focus being the Brain-Derived Neurotrophic Factor (BDNF) gene, given its impact on the integrity of the hippocampal memory system. Research into human navigation also considers the BDNF gene in relation to hippocampal dependent spatial processing. This speculative paper brings together trauma and spatial processing for the first time and presents exploratory research into their interactions with BDNF. We propose that quantifying the impact of BDNF on trauma and spatial processing is critical and may well explain individual differences in clinical trauma treatment outcomes and in navigation performance. Research has already shown that the BDNF gene influences PTSD severity and prevalence as well as navigation behaviour. However, more data are required to demonstrate the precise hippocampal dependent processing mechanisms behind these influences in different populations and environmental conditions. This paper provides insight from recent studies and calls for further research into the relationship between allocentric processing, trauma processing and BDNF. We argue that research into these neural mechanisms could transform PTSD clinical practice and professional support for individuals in trauma-exposing occupations such as emergency response, law enforcement and the military.

The effect of perceptual load on tactile spatial attention: Evidence from event-related potentials.

PubMed

Gherri, Elena; Berreby, Fiona

2017-10-15

To investigate whether tactile spatial attention is modulated by perceptual load, behavioural and electrophysiological measures were recorded during two spatial cuing tasks in which the difficulty of the target/non-target discrimination was varied (High and Low load tasks). Moreover, to study whether attentional modulations by load are sensitive to the availability of visual information, the High and Low load tasks were carried out under both illuminated and darkness conditions. ERPs to cued and uncued non-targets were compared as a function of task (High vs. Low load) and illumination condition (Light vs. Darkness). Results revealed that the locus of tactile spatial attention was determined by a complex interaction between perceptual load and illumination conditions during sensory-specific stages of processing. In the Darkness, earlier effects of attention were present in the High load than in the Low load task, while no difference between tasks emerged in the Light. By contrast, increased load was associated with stronger attention effects during later post-perceptual processing stages regardless of illumination conditions. These findings demonstrate that ERP correlates of tactile spatial attention are strongly affected by the perceptual load of the target/non-target discrimination. However, differences between illumination conditions show that the impact of load on tactile attention depends on the presence of visual information. Perceptual load is one of the many factors that contribute to determine the effects of spatial selectivity in touch. Copyright © 2017 Elsevier B.V. All rights reserved.

Emotion attribution to a non-humanoid robot in different social situations.

PubMed

Lakatos, Gabriella; Gácsi, Márta; Konok, Veronika; Brúder, Ildikó; Bereczky, Boróka; Korondi, Péter; Miklósi, Ádám

2014-01-01

In the last few years there was an increasing interest in building companion robots that interact in a socially acceptable way with humans. In order to interact in a meaningful way a robot has to convey intentionality and emotions of some sort in order to increase believability. We suggest that human-robot interaction should be considered as a specific form of inter-specific interaction and that human-animal interaction can provide a useful biological model for designing social robots. Dogs can provide a promising biological model since during the domestication process dogs were able to adapt to the human environment and to participate in complex social interactions. In this observational study we propose to design emotionally expressive behaviour of robots using the behaviour of dogs as inspiration and to test these dog-inspired robots with humans in inter-specific context. In two experiments (wizard-of-oz scenarios) we examined humans' ability to recognize two basic and a secondary emotion expressed by a robot. In Experiment 1 we provided our companion robot with two kinds of emotional behaviour ("happiness" and "fear"), and studied whether people attribute the appropriate emotion to the robot, and interact with it accordingly. In Experiment 2 we investigated whether participants tend to attribute guilty behaviour to a robot in a relevant context by examining whether relying on the robot's greeting behaviour human participants can detect if the robot transgressed a predetermined rule. Results of Experiment 1 showed that people readily attribute emotions to a social robot and interact with it in accordance with the expressed emotional behaviour. Results of Experiment 2 showed that people are able to recognize if the robot transgressed on the basis of its greeting behaviour. In summary, our findings showed that dog-inspired behaviour is a suitable medium for making people attribute emotional states to a non-humanoid robot.

Emotion Attribution to a Non-Humanoid Robot in Different Social Situations

PubMed Central

Lakatos, Gabriella; Gácsi, Márta; Konok, Veronika; Brúder, Ildikó; Bereczky, Boróka; Korondi, Péter; Miklósi, Ádám

2014-01-01

In the last few years there was an increasing interest in building companion robots that interact in a socially acceptable way with humans. In order to interact in a meaningful way a robot has to convey intentionality and emotions of some sort in order to increase believability. We suggest that human-robot interaction should be considered as a specific form of inter-specific interaction and that human–animal interaction can provide a useful biological model for designing social robots. Dogs can provide a promising biological model since during the domestication process dogs were able to adapt to the human environment and to participate in complex social interactions. In this observational study we propose to design emotionally expressive behaviour of robots using the behaviour of dogs as inspiration and to test these dog-inspired robots with humans in inter-specific context. In two experiments (wizard-of-oz scenarios) we examined humans' ability to recognize two basic and a secondary emotion expressed by a robot. In Experiment 1 we provided our companion robot with two kinds of emotional behaviour (“happiness” and “fear”), and studied whether people attribute the appropriate emotion to the robot, and interact with it accordingly. In Experiment 2 we investigated whether participants tend to attribute guilty behaviour to a robot in a relevant context by examining whether relying on the robot's greeting behaviour human participants can detect if the robot transgressed a predetermined rule. Results of Experiment 1 showed that people readily attribute emotions to a social robot and interact with it in accordance with the expressed emotional behaviour. Results of Experiment 2 showed that people are able to recognize if the robot transgressed on the basis of its greeting behaviour. In summary, our findings showed that dog-inspired behaviour is a suitable medium for making people attribute emotional states to a non-humanoid robot. PMID:25551218

Reproductive pair correlations and the clustering of organisms.

PubMed

Young, W R; Roberts, A J; Stuhne, G

2001-07-19

Clustering of organisms can be a consequence of social behaviour, or of the response of individuals to chemical and physical cues. Environmental variability can also cause clustering: for example, marine turbulence transports plankton and produces chlorophyll concentration patterns in the upper ocean. Even in a homogeneous environment, nonlinear interactions between species can result in spontaneous pattern formation. Here we show that a population of independent, random-walking organisms ('brownian bugs'), reproducing by binary division and dying at constant rates, spontaneously aggregates. Using an individual-based model, we show that clusters form out of spatially homogeneous initial conditions without environmental variability, predator-prey interactions, kinesis or taxis. The clustering mechanism is reproductively driven-birth must always be adjacent to a living organism. This clustering can overwhelm diffusion and create non-poissonian correlations between pairs (parent and offspring) or organisms, leading to the emergence of patterns.

Divergent migration within lake sturgeon (Acipenser fulvescens) populations: Multiple distinct patterns exist across an unrestricted migration corridor

USGS Publications Warehouse

Kessel, Steven T.; Hondorp, Darryl W.; Holbrook, Christopher; Boase, James C.; Chiotti, Justin A.; Thomas, Michael V.; Wills, Todd C.; Roseman, Edward; Drouin, Richard; Krueger, Charles C.

2018-01-01

Population structure, distribution, abundance, and dispersal arguably underpin the entire field of animal ecology, with consequences for regional species persistence, and provision of ecosystem services. Divergent migration behaviours among individuals or among populations is an important aspect of the ecology of highly-mobile animals, allowing populations to exploit spatially- or temporally-distributed food and space resources.This study investigated the spatial ecology of lake sturgeon (Acipenser fulvescens) within the barrier free Huron-Erie Corridor (HEC), which connects Lake Huron and Lake Erie of the North American Laurentian Great Lakes.Over six years (2011 – 2016), movements of 268 lake sturgeon in the HEC were continuously monitored across the Great Lakes using acoustic telemetry (10 yr battery life acoustic transmitters). Five distinct migration behaviours were identified with hierarchical cluster analysis, based on the phenology and duration of river and lake use.Lake sturgeon in the HEC were found to contain a high level of intraspecific divergent migration, including partial migration with the existence of residents. Specific behaviours included year-round river residency and multiple lake-migrant behaviours that involved movements between lakes and rivers. Over 85% of individuals were assign to migration behaviours as movements were consistently repeated over the study, which suggested migration behaviours were consistent and persistent in lake sturgeon. Differential use of specific rivers or lakes by acoustic-tagged lake sturgeon further subdivided individuals into 14 “contingents” (spatiotemporally segregated subgroups).Contingents associated with one river (Detroit or St. Clair) were rarely detected in the other river, which confirmed that lake sturgeon in the Detroit and St. Clair represent two semi-independent populations that could require separate management consideration for their conservation. The distribution of migration behaviours did not vary between populations, sexes, body size, or among release locations, which indicated that intrapopulation variability in migratory behaviour is a general feature of the spatial ecology of lake sturgeon in un-fragmented landscapes.

Optimal exploitation of spatially distributed trophic resources and population stability

USGS Publications Warehouse

Basset, A.; Fedele, M.; DeAngelis, D.L.

2002-01-01

The relationships between optimal foraging of individuals and population stability are addressed by testing, with a spatially explicit model, the effect of patch departure behaviour on individual energetics and population stability. A factorial experimental design was used to analyse the relevance of the behavioural factor in relation to three factors that are known to affect individual energetics; i.e. resource growth rate (RGR), assimilation efficiency (AE), and body size of individuals. The factorial combination of these factors produced 432 cases, and 1000 replicate simulations were run for each case. Net energy intake rates of the modelled consumers increased with increasing RGR, consumer AE, and consumer body size, as expected. Moreover, through their patch departure behaviour, by selecting the resource level at which they departed from the patch, individuals managed to substantially increase their net energy intake rates. Population stability was also affected by the behavioural factors and by the other factors, but with highly non-linear responses. Whenever resources were limiting for the consumers because of low RGR, large individual body size or low AE, population density at the equilibrium was directly related to the patch departure behaviour; on the other hand, optimal patch departure behaviour, which maximised the net energy intake at the individual level, had a negative influence on population stability whenever resource availability was high for the consumers. The consumer growth rate (r) and numerical dynamics, as well as the spatial and temporal fluctuations of resource density, which were the proximate causes of population stability or instability, were affected by the behavioural factor as strongly or even more strongly than by the others factors considered here. Therefore, patch departure behaviour can act as a feedback control of individual energetics, allowing consumers to optimise a potential trade-off between short-term individual fitness and long-term population stability. ?? 2002 Elsevier Science B.V. All rights reserved.

Interpersonal Interactions in Instrumental Lessons: Teacher/Student Verbal and Non-Verbal Behaviours

ERIC Educational Resources Information Center

Zhukov, Katie

2013-01-01

This study examined verbal and non-verbal teacher/student interpersonal interactions in higher education instrumental music lessons. Twenty-four lessons were videotaped and teacher/student behaviours were analysed using a researcher-designed instrument. The findings indicate predominance of student and teacher joke among the verbal behaviours with…

Trading Speed and Accuracy by Coding Time: A Coupled-circuit Cortical Model

PubMed Central

Standage, Dominic; You, Hongzhi; Wang, Da-Hui; Dorris, Michael C.

2013-01-01

Our actions take place in space and time, but despite the role of time in decision theory and the growing acknowledgement that the encoding of time is crucial to behaviour, few studies have considered the interactions between neural codes for objects in space and for elapsed time during perceptual decisions. The speed-accuracy trade-off (SAT) provides a window into spatiotemporal interactions. Our hypothesis is that temporal coding determines the rate at which spatial evidence is integrated, controlling the SAT by gain modulation. Here, we propose that local cortical circuits are inherently suited to the relevant spatial and temporal coding. In simulations of an interval estimation task, we use a generic local-circuit model to encode time by ‘climbing’ activity, seen in cortex during tasks with a timing requirement. The model is a network of simulated pyramidal cells and inhibitory interneurons, connected by conductance synapses. A simple learning rule enables the network to quickly produce new interval estimates, which show signature characteristics of estimates by experimental subjects. Analysis of network dynamics formally characterizes this generic, local-circuit timing mechanism. In simulations of a perceptual decision task, we couple two such networks. Network function is determined only by spatial selectivity and NMDA receptor conductance strength; all other parameters are identical. To trade speed and accuracy, the timing network simply learns longer or shorter intervals, driving the rate of downstream decision processing by spatially non-selective input, an established form of gain modulation. Like the timing network's interval estimates, decision times show signature characteristics of those by experimental subjects. Overall, we propose, demonstrate and analyse a generic mechanism for timing, a generic mechanism for modulation of decision processing by temporal codes, and we make predictions for experimental verification. PMID:23592967

Flight and echolocation behaviour of three vespertilionid bat species while commuting on flyways.

PubMed

Schaub, Andrea; Schnitzler, Hans-Ulrich

2007-12-01

This study compares the flight and echolocation behaviour of three vespertilionid bat species while they commute on flyways. We measured the bats' spatial position relative to vertical background contours and relative to the ground while recording their echolocation behaviour. In Myotis daubentonii, we found a significant influence of spatial context on the position and dimensions of flyways as well as on echolocation behaviour. In gap situations, flyways tended to be narrower and located closer to background structures, flight speeds were lower and the bandwidth of echolocation signals was larger than in edge situations. Differences in background structure did not affect flight and echolocation behaviour. When commuting in the same gap situation flyway positions and dimensions for M. daubentonii and Myotis brandtii were similar but differed from those of Pipistrellus pipistrellus, which were slightly higher and further out than those used by the Myotis species. In M. brandtii, flyway positions and dimensions remained constant over 3 years. We found species-dependent differences in signal structure, but pulse interval and flight speed were similar across all species. The influence of available space on the position of flyways, on flight speed and on echolocation behaviour is discussed.

What Are You or Who Are You? The Emergence of Social Interaction between Dog and an Unidentified Moving Object (UMO)

PubMed Central

Gergely, Anna; Petró, Eszter; Topál, József; Miklósi, Ádám

2013-01-01

Robots offer new possibilities for investigating animal social behaviour. This method enhances controllability and reproducibility of experimental techniques, and it allows also the experimental separation of the effects of bodily appearance (embodiment) and behaviour. In the present study we examined dogs’ interactive behaviour in a problem solving task (in which the dog has no access to the food) with three different social partners, two of which were robots and the third a human behaving in a robot-like manner. The Mechanical UMO (Unidentified Moving Object) and the Mechanical Human differed only in their embodiment, but showed similar behaviour toward the dog. In contrast, the Social UMO was interactive, showed contingent responsiveness and goal-directed behaviour and moved along varied routes. The dogs showed shorter looking and touching duration, but increased gaze alternation toward the Mechanical Human than to the Mechanical UMO. This suggests that dogs’ interactive behaviour may have been affected by previous experience with typical humans. We found that dogs also looked longer and showed more gaze alternations between the food and the Social UMO compared to the Mechanical UMO. These results suggest that dogs form expectations about an unfamiliar moving object within a short period of time and they recognise some social aspects of UMOs’ behaviour. This is the first evidence that interactive behaviour of a robot is important for evoking dogs’ social responsiveness. PMID:24015272

Effect of spatial organisation behaviour on upscaling the overland flow formation in an arable land

NASA Astrophysics Data System (ADS)

Silasari, Rasmiaditya; Blöschl, Günter

2014-05-01

Overland flow during rainfall events on arable land is important to investigate as it affects the land erosion process and water quality in the river. The formation of overland flow may happen through different ways (i.e. Hortonian overland flow, saturation excess overland flow) which is influenced by the surface and subsurface soil characteristics (i.e. land cover, soil infiltration rate). As the soil characteristics vary throughout the entire catchment, it will form distinct spatial patterns with organised or random behaviour. During the upscaling of hydrological processes from plot to catchment scale, this behaviour will become substantial since organised patterns will result in higher spatial connectivity and thus higher conductivity. However, very few of the existing studies explicitly address this effect of spatial organisations of the patterns in upscaling the hydrological processes to the catchment scale. This study will assess the upscaling of overland flow formation with concerns of spatial organisation behaviour of the patterns by application of direct field observations under natural conditions using video camera and soil moisture sensors and investigation of the underlying processes using a physical-based hydrology model. The study area is a Hydrological Open Air Laboratory (HOAL) located at Petzenkirchen, Lower Austria. It is a 64 ha catchment with land use consisting of arable land (87%), forest (6%), pasture (5%) and paved surfaces (2%). A video camera is installed 7m above the ground on a weather station mast in the middle of the arable land to monitor the overland flow patterns during rainfall events in a 2m x 6m plot scale. Soil moisture sensors with continuous measurement at different depth (5, 10, 20 and 50cm) are installed at points where the field is monitored by the camera. The patterns of overland flow formation and subsurface flow state at the plot scale will be generated using a coupled surface-subsurface flow physical-based hydrology model. The observation data will be assimilated into the model to verify the corresponding processes between surface and subsurface flow during the rainfall events. The patterns of conductivity then will be analyzed at catchment scale using the spatial stochastic analysis based on the classification of soil characteristics of the entire catchment. These patterns of conductivity then will be applied in the model at catchment scale to see how the organisational behaviour can affect the spatial connectivity of the hydrological processes and the results of the catchment response. A detailed modelling of the underlying processes in the physical-based model will allow us to see the direct effect of the spatial connectivity to the occurring surface and subsurface flow. This will improve the analysis of the effect of spatial organisations of the patterns in upscaling the hydrological processes from plot to catchment scale.

The effects of spatial and temporal heterogeneity on the population dynamics of four animal species in a Danish landscape

PubMed Central

Sibly, Richard M; Nabe-Nielsen, Jacob; Forchhammer, Mads C; Forbes, Valery E; Topping, Christopher J

2009-01-01

Background Variation in carrying capacity and population return rates is generally ignored in traditional studies of population dynamics. Variation is hard to study in the field because of difficulties controlling the environment in order to obtain statistical replicates, and because of the scale and expense of experimenting on populations. There may also be ethical issues. To circumvent these problems we used detailed simulations of the simultaneous behaviours of interacting animals in an accurate facsimile of a real Danish landscape. The models incorporate as much as possible of the behaviour and ecology of skylarks Alauda arvensis, voles Microtus agrestis, a ground beetle Bembidion lampros and a linyphiid spider Erigone atra. This allows us to quantify and evaluate the importance of spatial and temporal heterogeneity on the population dynamics of the four species. Results Both spatial and temporal heterogeneity affected the relationship between population growth rate and population density in all four species. Spatial heterogeneity accounted for 23–30% of the variance in population growth rate after accounting for the effects of density, reflecting big differences in local carrying capacity associated with the landscape features important to individual species. Temporal heterogeneity accounted for 3–13% of the variance in vole, skylark and spider, but 43% in beetles. The associated temporal variation in carrying capacity would be problematic in traditional analyses of density dependence. Return rates were less than one in all species and essentially invariant in skylarks, spiders and beetles. Return rates varied over the landscape in voles, being slower where there were larger fluctuations in local population sizes. Conclusion Our analyses estimated the traditional parameters of carrying capacities and return rates, but these are now seen as varying continuously over the landscape depending on habitat quality and the mechanisms of density dependence. The importance of our results lies in our demonstration that the effects of spatial and temporal heterogeneity must be accounted for if we are to have accurate predictive models for use in management and conservation. This is an area which until now has lacked an adequate theoretical framework and methodology. PMID:19549327

Monitoring Animal Behaviour and Environmental Interactions Using Wireless Sensor Networks, GPS Collars and Satellite Remote Sensing

PubMed Central

Handcock, Rebecca N.; Swain, Dave L.; Bishop-Hurley, Greg J.; Patison, Kym P.; Wark, Tim; Valencia, Philip; Corke, Peter; O'Neill, Christopher J.

2009-01-01

Remote monitoring of animal behaviour in the environment can assist in managing both the animal and its environmental impact. GPS collars which record animal locations with high temporal frequency allow researchers to monitor both animal behaviour and interactions with the environment. These ground-based sensors can be combined with remotely-sensed satellite images to understand animal-landscape interactions. The key to combining these technologies is communication methods such as wireless sensor networks (WSNs). We explore this concept using a case-study from an extensive cattle enterprise in northern Australia and demonstrate the potential for combining GPS collars and satellite images in a WSN to monitor behavioural preferences and social behaviour of cattle. PMID:22412327

Interpreting Intra-site Spatial Patterns in Seasonal Contexts: an Ethnoarchaeological Case Study from the Western Alps.

PubMed

Carrer, Francesco

2017-01-01

This paper deals with the ethnoarchaeological analysis of the spatial pattern of artefacts and ecofacts within two traditional pastoral huts (a dwelling and a seasonal dairy) in the uplands of Val Maudagna (Cuneo province, Italian western Alps). The composition of the ethnoarchaeological assemblages of the two huts was studied and compared; point pattern analysis was applied to identify spatial processes mirrored in the interactions between objects; Moran's I correlogram and empirical variogram were used to investigate the effects of trampling on the displacement of objects on the floor. The results were compared with information provided by the herder who still used the huts. The quantitative and ethnographical data enabled inferences to be made that can help in the interpretation of archaeological seasonal sites. The function of a seasonal site can be recognized, as can the impact of delayed curation on the composition of the assemblage and the importance of the intensity of occupation compared with the frequency of occupation. The spatial organization of activities is reflected in the spatial patterns of objects, with clearer identification of activity areas in intensively occupied sites, and there is evidence for the behaviour behind the spatial segregation of activities. Trampling is a crucial post-depositional factor in the displacement of artefacts and ecofacts, especially in non-intensively exploited sites. From a methodological point of view, this research is another example that highlights the importance of integrating quantitative methods (especially spatial analysis and geostatistical methods) and ethnoarchaeological data in order to improve the interpretation of archaeological sites and assemblages.

The behaviour of preschool children receiving fluoride varnish application in a community setting.

PubMed

Zhou, Y; Forbes, G M; Humphris, G M

2013-10-01

The behaviour of young children receiving mildly invasive dental preventive procedures in a community setting warrants more extensive research due to limitations in the literature.Objectives To document the behavioural profile of preschool children undergoing a preventive oral health intervention (fluoride varnish application) and to investigate this behaviour across children with different previous experience of the procedure, ages and initial anxiety states. Nurse-child interactions were video recorded and child behaviours coded and analysed using a specially developed coding scheme (SABICS). Behaviour frequency was measured and presented diagrammatically, followed by independent sample non-parametric tests to distinguish behavioural group differences. Three hundred and three interactions were coded out of 456 recorded application sessions. 'Nonverbal agreement' behaviour was observed most frequently compared to disruptive behaviours. Younger preschool children tended to exhibit 'interact with instrument' behaviour more frequently than older children regardless of whether they had had previous application experience. Children who showed signs of initial anxiety were likely to display more disruptive behaviours during the later stage of the procedure compared with non-anxious children. Dental staff working with preschool children are recommended to use encouragement-centred strategies to promote nonverbal cooperative behaviours in children. In addition, procedure instruments could be considered as a tool to gain child cooperation. Evidence of an autocorrelation effect of child behaviour was found, indicating that the early presentation of child behaviour predicted the behaviour of the child at later stages.

Motivational predictors of prosocial and antisocial behaviour in football.

PubMed

Kavussanu, Maria

2006-06-01

This study examined (a) the main and interactive effects of goal orientations and perceived motivational climate on prosocial and antisocial behaviour, and (b) whether number of seasons one has played for the team interacts with motivational climate in predicting prosocial and antisocial behaviour in association football. Participants were 325 male association football players, whose age ranged from 12 to 17 years. Athletes completed questionnaires measuring frequency of prosocial and antisocial behaviours in football, goal orientation, motivational climate and social desirability, and indicated the number of seasons they had played for their current team. Regression analyses revealed that task orientation and mastery climate were positive predictors of prosocial behaviour, whereas ego orientation and performance climate were positive predictors of antisocial behaviour. In addition, task orientation negatively predicted antisocial behaviour, while ego orientation negatively predicted prosocial behaviour. No significant interactions between task and ego orientation and mastery and performance motivational climate were found. Finally, mastery climate negatively predicted antisocial behaviour for those who had played many seasons for the team. In conclusion, strengthening task orientation and mastery climate and weakening ego orientation may enhance prosocial behaviour. However, for antisocial conduct to be eliminated from the context of association football, ego orientation and performance climate need to be tempered, as these constructs exert unique independent effects on antisocial behaviour.

Acute and constitutive increases in central serotonin levels reduce social play behaviour in peri-adolescent rats

PubMed Central

Schiepers, Olga J. G.; Schoffelmeer, Anton N. M.; Cuppen, Edwin; Vanderschuren, Louk J. M. J.

2007-01-01

Rationale Serotonin is an important modulator of social behaviour. Individual differences in serotonergic signalling are considered to be a marker of personality that is stable throughout lifetime. While a large body of evidence indicates that central serotonin levels are inversely related to aggression and sexual behaviour in adult rats, the relationship between serotonin and social behaviour during peri-adolescence has hardly been explored. Objective To study the effect of acute and constitutive increases in serotonin neurotransmission on social behaviour in peri-adolescent rats. Materials and methods Social behaviour in peri-adolesent rats (28–35 days old) was studied after genetic ablation of the serotonin transporter, causing constitutively increased extra-neuronal serotonin levels, and after acute treatment with the serotonin reuptake inhibitor fluoxetine or the serotonin releasing agent 3,4-methylenedioxymethamphetamine (MDMA). A distinction was made between social play behaviour that mainly occurs during peri-adolescence, and non-playful social interactions that are abundant during the entire lifespan of rats. Results In serotonin transporter knockout rats, social play behaviour was markedly reduced, while non-playful aspects of social interaction were unaffected. Acute treatment with fluoxetine or MDMA dose-dependently inhibited social play behaviour. MDMA also suppressed non-playful social interaction but at higher doses than those required to reduce social play. Fluoxetine did not affect non-playful social interaction. Conclusions These data show that both acute and constitutive increases in serotonergic neurotransmission reduce social play behaviour in peri-adolescent rats. Together with our previous findings of reduced aggressive and sexual behaviour in adult serotonin transporter knockout rats, these data support the notion that serotonin modulates social behaviour in a trait-like manner. PMID:17661017

A Model for an Angular Velocity-Tuned Motion Detector Accounting for Deviations in the Corridor-Centering Response of the Bee.

PubMed

Cope, Alex J; Sabo, Chelsea; Gurney, Kevin; Vasilaki, Eleni; Marshall, James A R

2016-05-01

We present a novel neurally based model for estimating angular velocity (AV) in the bee brain, capable of quantitatively reproducing experimental observations of visual odometry and corridor-centering in free-flying honeybees, including previously unaccounted for manipulations of behaviour. The model is fitted using electrophysiological data, and tested using behavioural data. Based on our model we suggest that the AV response can be considered as an evolutionary extension to the optomotor response. The detector is tested behaviourally in silico with the corridor-centering paradigm, where bees navigate down a corridor with gratings (square wave or sinusoidal) on the walls. When combined with an existing flight control algorithm the detector reproduces the invariance of the average flight path to the spatial frequency and contrast of the gratings, including deviations from perfect centering behaviour as found in the real bee's behaviour. In addition, the summed response of the detector to a unit distance movement along the corridor is constant for a large range of grating spatial frequencies, demonstrating that the detector can be used as a visual odometer.

A Model for an Angular Velocity-Tuned Motion Detector Accounting for Deviations in the Corridor-Centering Response of the Bee

PubMed Central

Sabo, Chelsea; Gurney, Kevin; Vasilaki, Eleni; Marshall, James A. R.

2016-01-01

We present a novel neurally based model for estimating angular velocity (AV) in the bee brain, capable of quantitatively reproducing experimental observations of visual odometry and corridor-centering in free-flying honeybees, including previously unaccounted for manipulations of behaviour. The model is fitted using electrophysiological data, and tested using behavioural data. Based on our model we suggest that the AV response can be considered as an evolutionary extension to the optomotor response. The detector is tested behaviourally in silico with the corridor-centering paradigm, where bees navigate down a corridor with gratings (square wave or sinusoidal) on the walls. When combined with an existing flight control algorithm the detector reproduces the invariance of the average flight path to the spatial frequency and contrast of the gratings, including deviations from perfect centering behaviour as found in the real bee’s behaviour. In addition, the summed response of the detector to a unit distance movement along the corridor is constant for a large range of grating spatial frequencies, demonstrating that the detector can be used as a visual odometer. PMID:27148968

A Critical Analysis of the Role of Wait Time in Classroom Interactions and the Effects on Student and Teacher Interactional Behaviours

ERIC Educational Resources Information Center

Ingram, Jenni; Elliott, Victoria

2016-01-01

Extending the pauses between teachers' and students' turns (wait time) has been recommended as a way of improving classroom learning. Drawing on the Conversation Analysis literature on classroom interactions alongside extracts of classroom interactions, the relationship between these pauses and the interactional behaviour of teachers and students…

Stability of subsystem solutions in agent-based models

NASA Astrophysics Data System (ADS)

Perc, Matjaž

2018-01-01

The fact that relatively simple entities, such as particles or neurons, or even ants or bees or humans, give rise to fascinatingly complex behaviour when interacting in large numbers is the hallmark of complex systems science. Agent-based models are frequently employed for modelling and obtaining a predictive understanding of complex systems. Since the sheer number of equations that describe the behaviour of an entire agent-based model often makes it impossible to solve such models exactly, Monte Carlo simulation methods must be used for the analysis. However, unlike pairwise interactions among particles that typically govern solid-state physics systems, interactions among agents that describe systems in biology, sociology or the humanities often involve group interactions, and they also involve a larger number of possible states even for the most simplified description of reality. This begets the question: when can we be certain that an observed simulation outcome of an agent-based model is actually stable and valid in the large system-size limit? The latter is key for the correct determination of phase transitions between different stable solutions, and for the understanding of the underlying microscopic processes that led to these phase transitions. We show that a satisfactory answer can only be obtained by means of a complete stability analysis of subsystem solutions. A subsystem solution can be formed by any subset of all possible agent states. The winner between two subsystem solutions can be determined by the average moving direction of the invasion front that separates them, yet it is crucial that the competing subsystem solutions are characterised by a proper composition and spatiotemporal structure before the competition starts. We use the spatial public goods game with diverse tolerance as an example, but the approach has relevance for a wide variety of agent-based models.

Cell Microenvironment Engineering and Monitoring for Tissue Engineering and Regenerative Medicine: The Recent Advances

PubMed Central

Barthes, Julien; Özçelik, Hayriye; Hindié, Mathilde; Ndreu-Halili, Albana; Hasan, Anwarul

2014-01-01

In tissue engineering and regenerative medicine, the conditions in the immediate vicinity of the cells have a direct effect on cells' behaviour and subsequently on clinical outcomes. Physical, chemical, and biological control of cell microenvironment are of crucial importance for the ability to direct and control cell behaviour in 3-dimensional tissue engineering scaffolds spatially and temporally. In this review, we will focus on the different aspects of cell microenvironment such as surface micro-, nanotopography, extracellular matrix composition and distribution, controlled release of soluble factors, and mechanical stress/strain conditions and how these aspects and their interactions can be used to achieve a higher degree of control over cellular activities. The effect of these parameters on the cellular behaviour within tissue engineering context is discussed and how these parameters are used to develop engineered tissues is elaborated. Also, recent techniques developed for the monitoring of the cell microenvironment in vitro and in vivo are reviewed, together with recent tissue engineering applications where the control of cell microenvironment has been exploited. Cell microenvironment engineering and monitoring are crucial parts of tissue engineering efforts and systems which utilize different components of the cell microenvironment simultaneously can provide more functional engineered tissues in the near future. PMID:25143954

Cell microenvironment engineering and monitoring for tissue engineering and regenerative medicine: the recent advances.

PubMed

Barthes, Julien; Özçelik, Hayriye; Hindié, Mathilde; Ndreu-Halili, Albana; Hasan, Anwarul; Vrana, Nihal Engin

2014-01-01

In tissue engineering and regenerative medicine, the conditions in the immediate vicinity of the cells have a direct effect on cells' behaviour and subsequently on clinical outcomes. Physical, chemical, and biological control of cell microenvironment are of crucial importance for the ability to direct and control cell behaviour in 3-dimensional tissue engineering scaffolds spatially and temporally. In this review, we will focus on the different aspects of cell microenvironment such as surface micro-, nanotopography, extracellular matrix composition and distribution, controlled release of soluble factors, and mechanical stress/strain conditions and how these aspects and their interactions can be used to achieve a higher degree of control over cellular activities. The effect of these parameters on the cellular behaviour within tissue engineering context is discussed and how these parameters are used to develop engineered tissues is elaborated. Also, recent techniques developed for the monitoring of the cell microenvironment in vitro and in vivo are reviewed, together with recent tissue engineering applications where the control of cell microenvironment has been exploited. Cell microenvironment engineering and monitoring are crucial parts of tissue engineering efforts and systems which utilize different components of the cell microenvironment simultaneously can provide more functional engineered tissues in the near future.

CHARLES HORTON COOLEY'S THEORY OF TRANSPORTATION: TOWARDS AN INTERACTIONIST APPROACH FOR TRANSPORTATION STUDIES

NASA Astrophysics Data System (ADS)

Nakano, Takeshi

The aim of this paper is to interpret Charles Horton Cooley's "Theory of Transportation", situating it in his interactionist sociology of communication and social process. Cooley defines transportation as a spatial and physical form of communication. He also develops a interactionist theory of valuation and articulates that value as an end of action is shaped an d transformed by communication and interaction. These insights suggest that transportation as a form of communication will change and develop economic society through transforming personal desires and values so as to change behaviours. Cooley's theory implies that an interactionist approach is useful for understanding the subjective side of phenomena of transportation.

A map of abstract relational knowledge in the human hippocampal-entorhinal cortex.

PubMed

Garvert, Mona M; Dolan, Raymond J; Behrens, Timothy Ej

2017-04-27

The hippocampal-entorhinal system encodes a map of space that guides spatial navigation. Goal-directed behaviour outside of spatial navigation similarly requires a representation of abstract forms of relational knowledge. This information relies on the same neural system, but it is not known whether the organisational principles governing continuous maps may extend to the implicit encoding of discrete, non-spatial graphs. Here, we show that the human hippocampal-entorhinal system can represent relationships between objects using a metric that depends on associative strength. We reconstruct a map-like knowledge structure directly from a hippocampal-entorhinal functional magnetic resonance imaging adaptation signal in a situation where relationships are non-spatial rather than spatial, discrete rather than continuous, and unavailable to conscious awareness. Notably, the measure that best predicted a behavioural signature of implicit knowledge and blood oxygen level-dependent adaptation was a weighted sum of future states, akin to the successor representation that has been proposed to account for place and grid-cell firing patterns.

The Effects on Students' Emotional and Behavioural Difficulties of Teacher-Student Interactions, Students' Social Skills and Classroom Context

ERIC Educational Resources Information Center

Poulou, Maria

2014-01-01

Children's emotional and behavioural difficulties are the result of multiple individual, social and contextual factors working in concert. The current paper proposes a theoretical framework for interpreting students' emotional and behavioural difficulties in classrooms, by taking into consideration teacher-student interactions, students' social…

The Behavioural Phenotype of Smith-Magenis Syndrome: Evidence for a Gene-Environment Interaction

ERIC Educational Resources Information Center

Taylor, L.; Oliver, C.

2008-01-01

Background: Behaviour problems and a preference for adult contact are reported to be prominent in the phenotype of Smith-Magenis syndrome. In this study we examined the relationship between social interactions and self-injurious and aggressive/disruptive behaviour in Smith-Magenis syndrome to explore potential operant reinforcement of problem…

Communication and abnormal behaviour.

PubMed

Crown, S

1979-01-01

In this paper the similarities between normal and abnormal behaviour are emphasized and selected aspects of communication, normal and aberrant, between persons are explored. Communication in a social system may be verbal or non-verbal: one person's actions cause a response in another person. This response may be cognitive, behavioural or physiological. Communication may be approached through the individual, the social situation or social interaction. Psychoanalysis approaches the individual in terms of the coded communications of psychoneurotic symptoms or psychotic behaviour; the humanist-existential approach is concerned more with emotional expression. Both approaches emphasize the development of individual identity. The interaction between persons and their social background is stressed. Relevant are sociological concepts such as illness behaviour, stigma, labelling, institutionalization and compliance. Two approaches to social interactions are considered: the gamesplaying metaphor, e.g. back pain as a psychosocial manipulation--the 'pain game'; and the 'spiral of reciprocal perspectives' which emphasizes the interactional complexities of social perceptions. Communicatory aspects of psychological treatments are noted: learning a particular metaphor such as 'resolution' of the problem (psychotherapy), learning more 'rewarding' behaviour (learning theory) or learning authenticity or self-actualization (humanist-existential).

Ants regulate colony spatial organization using multiple chemical road-signs

PubMed Central

Heyman, Yael; Shental, Noam; Brandis, Alexander; Hefetz, Abraham; Feinerman, Ofer

2017-01-01

Communication provides the basis for social life. In ant colonies, the prevalence of local, often chemically mediated, interactions introduces strong links between communication networks and the spatial distribution of ants. It is, however, unknown how ants identify and maintain nest chambers with distinct functions. Here, we combine individual tracking, chemical analysis and machine learning to decipher the chemical signatures present on multiple nest surfaces. We present evidence for several distinct chemical ‘road-signs' that guide the ants' movements within the dark nest. These chemical signatures can be used to classify nest chambers with different functional roles. Using behavioural manipulations, we demonstrate that at least three of these chemical signatures are functionally meaningful and allow ants from different task groups to identify their specific nest destinations, thus facilitating colony coordination and stabilization. The use of multiple chemicals that assist spatiotemporal guidance, segregation and pattern formation is abundant in multi-cellular organisms. Here, we provide a rare example for the use of these principles in the ant colony. PMID:28569746

Ants regulate colony spatial organization using multiple chemical road-signs.

PubMed

Heyman, Yael; Shental, Noam; Brandis, Alexander; Hefetz, Abraham; Feinerman, Ofer

2017-06-01

Communication provides the basis for social life. In ant colonies, the prevalence of local, often chemically mediated, interactions introduces strong links between communication networks and the spatial distribution of ants. It is, however, unknown how ants identify and maintain nest chambers with distinct functions. Here, we combine individual tracking, chemical analysis and machine learning to decipher the chemical signatures present on multiple nest surfaces. We present evidence for several distinct chemical 'road-signs' that guide the ants' movements within the dark nest. These chemical signatures can be used to classify nest chambers with different functional roles. Using behavioural manipulations, we demonstrate that at least three of these chemical signatures are functionally meaningful and allow ants from different task groups to identify their specific nest destinations, thus facilitating colony coordination and stabilization. The use of multiple chemicals that assist spatiotemporal guidance, segregation and pattern formation is abundant in multi-cellular organisms. Here, we provide a rare example for the use of these principles in the ant colony.

Spatial Language, Visual Attention, and Perceptual Simulation

ERIC Educational Resources Information Center

Coventry, Kenny R.; Lynott, Dermot; Cangelosi, Angelo; Monrouxe, Lynn; Joyce, Dan; Richardson, Daniel C.

2010-01-01

Spatial language descriptions, such as "The bottle is over the glass", direct the attention of the hearer to particular aspects of the visual world. This paper asks how they do so, and what brain mechanisms underlie this process. In two experiments employing behavioural and eye tracking methodologies we examined the effects of spatial language on…

How social factors and behavioural strategies affect feeding and social interaction patterns in pigs.

PubMed

Boumans, Iris J M M; de Boer, Imke J M; Hofstede, Gert Jan; Bokkers, Eddie A M

2018-04-26

Animals living in groups compete for food resources and face food conflicts. These conflicts are affected by social factors (e.g. competition level) and behavioural strategies (e.g. avoidance). This study aimed to deepen our understanding of the complex interactions between social factors and behavioural strategies affecting feeding and social interaction patterns in animals. We focused on group-housed growing pigs, Sus scrofa, which typically face conflicts around the feeder, and of which patterns in various competitive environments (i.e. pig:feeder ratio) have been documented soundly. An agent-based model was developed to explore how interactions among social factors and behavioural strategies can affect various feeding and social interaction patterns differently under competitive situations. Model results show that pig and diet characteristics interact with group size and affect daily feeding patterns (e.g. feed intake and feeding time) and conflicts around the feeder. The level of competition can cause a turning point in feeding and social interaction patterns. Beyond a certain point of competition, meal-based (e.g. meal frequency) and social interaction patterns (e.g. displacements) are determined mainly by behavioural strategies. The average daily feeding time can be used to predict the group size at which this turning point occurs. Under the model's assumptions, social facilitation was relatively unimportant in the causation of behavioural patterns in pigs. To validate our model, simulated patterns were compared with empirical patterns in conventionally housed pigs. Similarities between empirical and model patterns support the model results. Our model can be used as a tool in further research for studying the effects of social factors and group dynamics on individual variation in feeding and social interaction patterns in pigs, as well as in other animal species. Copyright © 2018 Elsevier Inc. All rights reserved.

Tracing the phase of focused broadband laser pulses

NASA Astrophysics Data System (ADS)

Hoff, Dominik; Krüger, Michael; Maisenbacher, Lothar; Sayler, A. M.; Paulus, Gerhard G.; Hommelhoff, Peter

2017-10-01

Precise knowledge of the behaviour of the phase of light in a focused beam is fundamental to understanding and controlling laser-driven processes. More than a hundred years ago, an axial phase anomaly for focused monochromatic light beams was discovered and is now commonly known as the Gouy phase. Recent theoretical work has brought into question the validity of applying this monochromatic phase formulation to the broadband pulses becoming ubiquitous today. Based on electron backscattering at sharp nanometre-scale metal tips, a method is available to measure light fields with sub-wavelength spatial resolution and sub-optical-cycle time resolution. Here we report such a direct, three-dimensional measurement of the spatial dependence of the optical phase of a focused, 4-fs, near-infrared pulsed laser beam. The observed optical phase deviates substantially from the monochromatic Gouy phase--exhibiting a much more complex spatial dependence, both along the propagation axis and in the radial direction. In our measurements, these significant deviations are the rule and not the exception for focused, broadband laser pulses. Therefore, we expect wide ramifications for all broadband laser-matter interactions, such as in high-harmonic and attosecond pulse generation, femtochemistry, ophthalmological optical coherence tomography and light-wave electronics.

The role of spatial and temporal radiation deposition in inertial fusion chambers: the case of HiPER

NASA Astrophysics Data System (ADS)

Alvarez, J.; Garoz, D.; Gonzalez-Arrabal, R.; Rivera, A.; Perlado, M.

2011-05-01

The first wall armour for the reactor chamber of HiPER will have to face short energy pulses of 5 to 20 MJ mostly in the form of x-rays and charged particles at a repetition rate of 5-10 Hz. Armour material and chamber dimensions have to be chosen to avoid/minimize damage to the chamber, ensuring the proper functioning of the facility during its planned lifetime. The maximum energy fluence that the armour can withstand without risk of failure, is determined by temporal and spatial deposition of the radiation energy inside the material. In this paper, simulations on the thermal effect of the radiation-armour interaction are carried out with an increasing definition of the temporal and spatial deposition of energy to prove their influence on the final results. These calculations will lead us to present the first values of the thermo-mechanical behaviour of the tungsten armour designed for the HiPER project under a shock ignition target of 48 MJ. The results will show that only the crossing of the plasticity limit in the first few micrometres might be a threat after thousands of shots for the survivability of the armour.

The Effects of Dominance on Leadership and Energetic Gain: A Dynamic Game between Pairs of Social Foragers

PubMed Central

Rands, Sean A.

2011-01-01

Although social behaviour can bring many benefits to an individual, there are also costs that may be incurred whenever the members of a social group interact. The formation of dominance hierarchies could offer a means of reducing some of the costs of social interaction, but individuals within the hierarchy may end up paying differing costs dependent upon their position within the hierarchy. These differing interaction costs may therefore influence the behaviour of the group, as subordinate individuals may experience very different benefits and costs to dominants when the group is conducting a given behaviour. Here, a state-dependent dynamic game is described which considers a pair of social foragers where there is a set dominance relationship within the pair. The model considers the case where the subordinate member of the pair pays an interference cost when it and the dominant individual conduct specific pairs of behaviours together. The model demonstrates that if the subordinate individual pays these energetic costs when it interacts with the dominant individual, this has effects upon the behaviour of both subordinate and the dominant individuals. Including interaction costs increases the amount of foraging behaviour both individuals conduct, with the behaviour of the pair being driven by the subordinate individual. The subordinate will tend to be the lighter individual for longer periods of time when interaction costs are imposed. This supports earlier suggestions that lighter individuals should act as the decision-maker within the pair, giving leadership-like behaviours that are based upon energetic state. Pre-existing properties of individuals such as their dominance will be less important for determining which individual makes the decisions for the pair. This suggests that, even with strict behavioural hierarchies, identifying which individual is the dominant one is not sufficient for identifying which one is the leader. PMID:22028645

Inelastic behaviour of collagen networks in cell-matrix interactions and mechanosensation.

PubMed

Mohammadi, Hamid; Arora, Pamma D; Simmons, Craig A; Janmey, Paul A; McCulloch, Christopher A

2015-01-06

The mechanical properties of extracellular matrix proteins strongly influence cell-induced tension in the matrix, which in turn influences cell function. Despite progress on the impact of elastic behaviour of matrix proteins on cell-matrix interactions, little is known about the influence of inelastic behaviour, especially at the large and slow deformations that characterize cell-induced matrix remodelling. We found that collagen matrices exhibit deformation rate-dependent behaviour, which leads to a transition from pronounced elastic behaviour at fast deformations to substantially inelastic behaviour at slow deformations (1 μm min(-1), similar to cell-mediated deformation). With slow deformations, the inelastic behaviour of floating gels was sensitive to collagen concentration, whereas attached gels exhibited similar inelastic behaviour independent of collagen concentration. The presence of an underlying rigid support had a similar effect on cell-matrix interactions: cell-induced deformation and remodelling were similar on 1 or 3 mg ml(-1) attached collagen gels while deformations were two- to fourfold smaller in floating gels of high compared with low collagen concentration. In cross-linked collagen matrices, which did not exhibit inelastic behaviour, cells did not respond to the presence of the underlying rigid foundation. These data indicate that at the slow rates of collagen compaction generated by fibroblasts, the inelastic responses of collagen gels, which are influenced by collagen concentration and the presence of an underlying rigid foundation, are important determinants of cell-matrix interactions and mechanosensation. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Inelastic behaviour of collagen networks in cell–matrix interactions and mechanosensation

PubMed Central

Mohammadi, Hamid; Arora, Pamma D.; Simmons, Craig A.; Janmey, Paul A.; McCulloch, Christopher A.

2015-01-01

The mechanical properties of extracellular matrix proteins strongly influence cell-induced tension in the matrix, which in turn influences cell function. Despite progress on the impact of elastic behaviour of matrix proteins on cell–matrix interactions, little is known about the influence of inelastic behaviour, especially at the large and slow deformations that characterize cell-induced matrix remodelling. We found that collagen matrices exhibit deformation rate-dependent behaviour, which leads to a transition from pronounced elastic behaviour at fast deformations to substantially inelastic behaviour at slow deformations (1 μm min−1, similar to cell-mediated deformation). With slow deformations, the inelastic behaviour of floating gels was sensitive to collagen concentration, whereas attached gels exhibited similar inelastic behaviour independent of collagen concentration. The presence of an underlying rigid support had a similar effect on cell–matrix interactions: cell-induced deformation and remodelling were similar on 1 or 3 mg ml−1 attached collagen gels while deformations were two- to fourfold smaller in floating gels of high compared with low collagen concentration. In cross-linked collagen matrices, which did not exhibit inelastic behaviour, cells did not respond to the presence of the underlying rigid foundation. These data indicate that at the slow rates of collagen compaction generated by fibroblasts, the inelastic responses of collagen gels, which are influenced by collagen concentration and the presence of an underlying rigid foundation, are important determinants of cell–matrix interactions and mechanosensation. PMID:25392399

Investigating low adaptive behaviour and presence of the triad of impairments characteristic of autistic spectrum disorder as indicators of risk for challenging behaviour among adults with intellectual disabilities.

PubMed

Felce, D; Kerr, M

2013-02-01

Identification of possible personal indicators of risk for challenging behaviour has generally been through association in cross-sectional prevalence studies, but few analyses have controlled for intercorrelation between potential risk factors. The aim was to investigate the extent to which gender, age, presence of the triad of impairments characteristic of autism and level of adaptive behaviour were independently associated with level of challenging behaviour among adults with intellectual disabilities. Five datasets were merged to produce information on challenging behaviour, adaptive behaviour, presence of the triad of impairments, gender and age of 818 adults. Variables were entered into a multivariate linear regression, which also tested the interaction between the presence of the triad of impairments and level of adaptive behaviour. Presence of the triad of impairments, level of adaptive behaviour, their interaction, and age, but not gender, significantly and independently contributed to the prediction of challenging behaviour. Presence/absence of the triad of impairments moderated the effect of adaptive behaviour on challenging behaviour. The inverse relationship found in the absence of the triad of impairments was virtually removed when present. This study has shown that it is necessary to control for intercorrelation between potential risk factors for challenging behaviour and to explore how interaction between them might moderate associations. © 2012 The Author. Journal of Intellectual Disability Research © 2012 Blackwell Publishing Ltd.

The relationship of self-regulation and aggression: an empirical test of personality systems interaction theory.

PubMed

Ross, Thomas; Fontao, María Isabel

2008-10-01

On the basis of personality systems interaction (PSI) theory, the authors examine self-regulation, conflict behaviour, behavioural resources, and personality disorders in a sample of 83 male offenders and explore the role self-regulatory variables play with respect to aggressive behaviour. Although substantial correlations between self-regulatory functions and aggressive behaviour were found, these variables did not predict aggression in a subsequent regression analysis with measures of self-regulation, conflict behaviour, and personality disorders as independent variables. Antisocial behaviour, behavioural self-control, and affect were among the strongest predictors of aggression. Specific predictions based on PSI theory could not be confirmed. Theoretical implications of the findings are discussed and put into relation with treatment issues of offenders.

Behavioural phenotyping assays for mouse models of autism

PubMed Central

Silverman, Jill L.; Yang, Mu; Lord, Catherine; Crawley, Jacqueline N.

2011-01-01

Autism is a heterogeneous neurodevelopmental disorder of unknown aetiology that affects 1 in 100–150 individuals. Diagnosis is based on three categories of behavioural criteria: abnormal social interactions, communication deficits and repetitive behaviours. Strong evidence for a genetic basis has prompted the development of mouse models with targeted mutations in candidate genes for autism. As the diagnostic criteria for autism are behavioural, phenotyping these mouse models requires behavioural assays with high relevance to each category of the diagnostic symptoms. Behavioural neuroscientists are generating a comprehensive set of assays for social interaction, communication and repetitive behaviours to test hypotheses about the causes of austism. Robust phenotypes in mouse models hold great promise as translational tools for discovering effective treatments for components of autism spectrum disorders. PMID:20559336

Maternal Communicative Behaviours and Interaction Quality as Predictors of Language Development: Findings from a Community-Based Study of Slow-to-Talk Toddlers

ERIC Educational Resources Information Center

Conway, Laura J.; Levickis, Penny A.; Smith, Jodie; Mensah, Fiona; Wake, Melissa; Reilly, Sheena

2018-01-01

Background: Identifying risk and protective factors for language development informs interventions for children with developmental language disorder (DLD). Maternal responsive and intrusive communicative behaviours are associated with language development. Mother-child interaction quality may influence how children use these behaviours in language…

Spectacular phenomena and limits to rationality in genetic and cultural evolution.

PubMed Central

Enquist, Magnus; Arak, Anthony; Ghirlanda, Stefano; Wachtmeister, Carl-Adam

2002-01-01

In studies of both animal and human behaviour, game theory is used as a tool for understanding strategies that appear in interactions between individuals. Game theory focuses on adaptive behaviour, which can be attained only at evolutionary equilibrium. We suggest that behaviour appearing during interactions is often outside the scope of such analysis. In many types of interaction, conflicts of interest exist between players, fuelling the evolution of manipulative strategies. Such strategies evolve out of equilibrium, commonly appearing as spectacular morphology or behaviour with obscure meaning, to which other players may react in non-adaptive, irrational ways. We present a simple model to show some limitations of the game-theory approach, and outline the conditions in which evolutionary equilibria cannot be maintained. Evidence from studies of biological interactions seems to support the view that behaviour is often not at equilibrium. This also appears to be the case for many human cultural traits, which have spread rapidly despite the fact that they have a negative influence on reproduction. PMID:12495515

Spectacular phenomena and limits to rationality in genetic and cultural evolution.

PubMed

Enquist, Magnus; Arak, Anthony; Ghirlanda, Stefano; Wachtmeister, Carl-Adam

2002-11-29

In studies of both animal and human behaviour, game theory is used as a tool for understanding strategies that appear in interactions between individuals. Game theory focuses on adaptive behaviour, which can be attained only at evolutionary equilibrium. We suggest that behaviour appearing during interactions is often outside the scope of such analysis. In many types of interaction, conflicts of interest exist between players, fuelling the evolution of manipulative strategies. Such strategies evolve out of equilibrium, commonly appearing as spectacular morphology or behaviour with obscure meaning, to which other players may react in non-adaptive, irrational ways. We present a simple model to show some limitations of the game-theory approach, and outline the conditions in which evolutionary equilibria cannot be maintained. Evidence from studies of biological interactions seems to support the view that behaviour is often not at equilibrium. This also appears to be the case for many human cultural traits, which have spread rapidly despite the fact that they have a negative influence on reproduction.

Social information influences trust behaviour in adolescents.

PubMed

Lee, Nikki C; Jolles, Jelle; Krabbendam, Lydia

2016-01-01

Trust plays an integral role in daily interactions within adolescents' social environment. Using a trust game paradigm, this study investigated the modulating influence of social information about three interaction partners on trust behaviour in adolescents aged 12-18 (N = 845). After receiving information about their interaction partners prior to the task, participants were most likely to share with a 'good' partner and rate this partner as most trustworthy. Over the course of the task all interaction partners showed similar levels of trustworthy behaviour, but overall participants continued to trust and view the good partner as more trustworthy than 'bad' and 'neutral' partners throughout the game. However, with age the ability to overcome prior social information and adapt trust behaviour improved: middle and late adolescents showed a larger decrease in trust of the good partner than early adolescents, and late adolescents were more likely to reward trustworthy behaviour from the negative partner. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Brain and behaviour phenotyping of a mouse model of neurofibromatosis type-1: an MRI/DTI study on social cognition.

PubMed

Petrella, L I; Cai, Y; Sereno, J V; Gonçalves, S I; Silva, A J; Castelo-Branco, M

2016-09-01

Neurofibromatosis type-1 (NF1) is a common neurogenetic disorder and an important cause of intellectual disability. Brain-behaviour associations can be examined in vivo using morphometric magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) to study brain structure. Here, we studied structural and behavioural phenotypes in heterozygous Nf1 mice (Nf1(+/-) ) using T2-weighted imaging MRI and DTI, with a focus on social recognition deficits. We found that Nf1(+/-) mice have larger volumes than wild-type (WT) mice in regions of interest involved in social cognition, the prefrontal cortex (PFC) and the caudate-putamen (CPu). Higher diffusivity was found across a distributed network of cortical and subcortical brain regions, within and beyond these regions. Significant differences were observed for the social recognition test. Most importantly, significant structure-function correlations were identified concerning social recognition performance and PFC volumes in Nf1(+/-) mice. Analyses of spatial learning corroborated the previously known deficits in the mutant mice, as corroborated by platform crossings, training quadrant time and average proximity measures. Moreover, linear discriminant analysis of spatial performance identified 2 separate sub-groups in Nf1(+/-) mice. A significant correlation between quadrant time and CPu volumes was found specifically for the sub-group of Nf1(+/-) mice with lower spatial learning performance, suggesting additional evidence for reorganization of this region. We found strong evidence that social and spatial cognition deficits can be associated with PFC/CPu structural changes and reorganization in NF1. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Environmental justice and health practices: understanding how health inequities arise at the local level.

PubMed

Frohlich, Katherine L; Abel, Thomas

2014-02-01

While empirical evidence continues to show that people living in low socio-economic status neighbourhoods are less likely to engage in health-enhancing behaviour, our understanding of why this is so remains less than clear. We suggest that two changes could take place to move from description to understanding in this field; (i) a move away from the established concept of individual health behaviour to a contextualised understanding of health practices; and (ii) a switch from focusing on health inequalities in outcomes to health inequities in conditions. We apply Pierre Bourdieu's theory on capital interaction but find it insufficient with regard to the role of agency for structural change. We therefore introduce Amartya Sen's capability approach as a useful link between capital interaction theory and action to reduce social inequities in health-related practices. Sen's capability theory also elucidates the importance of discussing unequal chances in terms of inequity, rather than inequality, in order to underscore the moral nature of inequalities. We draw on the discussion in social geography on environmental injustice, which also underscores the moral nature of the spatial distribution of opportunities. The article ends by applying this approach to the 'Interdisciplinary study of inequalities in smoking' framework. © 2013 The Authors. Sociology of Health & Illness © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

Coupling of a distributed stakeholder-built system dynamics socio-economic model with SAHYSMOD for sustainable soil salinity management - Part 1: Model development

NASA Astrophysics Data System (ADS)

Inam, Azhar; Adamowski, Jan; Prasher, Shiv; Halbe, Johannes; Malard, Julien; Albano, Raffaele

2017-08-01

Effective policies, leading to sustainable management solutions for land and water resources, require a full understanding of interactions between socio-economic and physical processes. However, the complex nature of these interactions, combined with limited stakeholder engagement, hinders the incorporation of socio-economic components into physical models. The present study addresses this challenge by integrating the physical Spatial Agro Hydro Salinity Model (SAHYSMOD) with a participatory group-built system dynamics model (GBSDM) that includes socio-economic factors. A stepwise process to quantify the GBSDM is presented, along with governing equations and model assumptions. Sub-modules of the GBSDM, describing agricultural, economic, water and farm management factors, are linked together with feedbacks and finally coupled with the physically based SAHYSMOD model through commonly used tools (i.e., MS Excel and a Python script). The overall integrated model (GBSDM-SAHYSMOD) can be used to help facilitate the role of stakeholders with limited expertise and resources in model and policy development and implementation. Following the development of the integrated model, a testing methodology was used to validate the structure and behavior of the integrated model. Model robustness under different operating conditions was also assessed. The model structure was able to produce anticipated real behaviours under the tested scenarios, from which it can be concluded that the formulated structures generate the right behaviour for the right reasons.

High-resolution infrared thermography for capturing wildland fire behaviour - RxCADRE 2012

Treesearch

Joseph J. O’Brien; E. Louise Loudermilk; Benjamin Hornsby; Andrew T. Hudak; Benjamin C. Bright; Matthew B. Dickinson; J. Kevin Hiers; Casey Teske; Roger D. Ottmar

2016-01-01

Wildland fire radiant energy emission is one of the only measurements of combustion that can be made at wide spatial extents and high temporal and spatial resolutions. Furthermore, spatially and temporally explicit measurements are critical for making inferences about fire effects and useful for examining patterns of fire spread. In this study we describe our...

Divergent pheromone-mediated insect behaviour under global atmospheric change

Treesearch

Edward B. Mondor; Michelle N. Tremblay; Caroline S. Awmack; Richard L. Lindroth

2004-01-01

While the effects of global atmospheric changes on vegetation and resulting insect populations('bottom-up interactions') are being increasingly studied, how these gases modify interactions among insects and their natural enemies ('top-down interactions') is less clear. As natural enemy efficacy is governed largely by behavioural mechanisms, altered...

An Exploratory Case Study of Young Children's Interactive Play Behaviours with a Non-English Speaking Child

ERIC Educational Resources Information Center

Lee, Joohi; Md-Yunus, Sham'ah; Son, Won In; Meadows, Michelle

2009-01-01

This study is an examination of preschool-age English speaking children's interactive play behaviours with a non-English speaking child (NEC). The play types of a NEC were reported using the Parten's categories of solitary, parallel and interactive play. In addition, English-speaking children's interactive play with a NEC were reported in this…

Environmental influences on the spatial ecology and spawning behaviour of an estuarine-resident fish, Macquaria colonorum

NASA Astrophysics Data System (ADS)

Walsh, C. T.; Reinfelds, I. V.; Ives, M. C.; Gray, C. A.; West, R. J.; van der Meulen, D. E.

2013-02-01

Estuarine-resident fishes are highly susceptible to the effects of environmental and anthropogenic impacts on their assemblages and habitats. We investigated the distribution, movement and spawning behaviour of estuary perch, Macquaria colonorum, in response to selected environmental variables using an acoustic telemetry array in a large tidal river in south-eastern (SE) Australia. Adult M. colonorum were monitored for up to two years, covering two consecutive spawning periods between September 2007 and 2009. Salinity, water temperature and river flows all had a significant relationship with their estuarine distribution. In particular, large-scale movements were influenced by large freshwater inflow events and the resultant reduction in salinity levels, together with the seasonal cooling and warming trends in water temperatures associated with spawning behaviour. During the winter months, male and female M. colonorum migrated from their upper estuarine home ranges to the lower estuarine spawning grounds in synchrony, with numbers of individual visits by both sexes consistently higher in the 'wetter' winter/spring period of 2008. Location, arrival, departure and occupation time within the spawning grounds were similar between sexes and years. Both resident and migrating M. colonorum exhibited strong diel, and to a lesser extent, tidal behavioural patterns, with fish more likely to be detected at night and during the ebb tides. It is postulated that the effect of environmental fluctuations on the distribution and movement of M. colonorum is influenced by behavioural mechanisms in response to osmoregulatory stress, predator-prey interactions and reproductive activity. The results also demonstrate the importance of accounting for autocorrelation inherent in telemetry data, and for developing management strategies that are more robust to the effect of future climate trends on estuarine fish populations.

A developmental dose-response analysis of the effects of methylphenidate on the peer interactions of attention deficit disordered boys.

PubMed

Cunningham, C E; Siegel, L S; Offord, D R

1985-11-01

Mixed dyads of 42 normal and 42 ADD boys were videotaped in free play, co-operative task, and simulated classrooms. ADD boys received placebo, 0.15 mg/kg, and 0.50 mg/kg of methylphenidate. ADD boys were more active and off task, watched peers less, and scored lower on mathematics and visual-motor tasks. Older boys interacted less, ignored peer interactions and play more frequently, were less controlling, and more compliant. In class, methylphenidate improved visual motor scores, and reduced the controlling behaviour, activity level, and off task behaviour of ADD boys. Normal peers displayed reciprocal reductions in controlling behaviour, activity level, and off task behaviour.

Longitudinal Trajectories of Intellectual and Adaptive Functioning in Adolescents and Adults with Williams Syndrome

ERIC Educational Resources Information Center

Fisher, M. H.; Lense, M. D.; Dykens, E. M.

2016-01-01

Background: Williams syndrome (WS) is associated with a distinct cognitive-behavioural phenotype including mild to moderate intellectual disability, visual-spatial deficits, hypersociability, inattention and anxiety. Researchers typically characterise samples of individuals with WS by their intellectual functioning and adaptive behaviour. Because…

Mirroring and beyond: coupled dynamics as a generalized framework for modelling social interactions

PubMed Central

Hasson, Uri; Frith, Chris D.

2016-01-01

When people observe one another, behavioural alignment can be detected at many levels, from the physical to the mental. Likewise, when people process the same highly complex stimulus sequences, such as films and stories, alignment is detected in the elicited brain activity. In early sensory areas, shared neural patterns are coupled to the low-level properties of the stimulus (shape, motion, volume, etc.), while in high-order brain areas, shared neural patterns are coupled to high-levels aspects of the stimulus, such as meaning. Successful social interactions require such alignments (both behavioural and neural), as communication cannot occur without shared understanding. However, we need to go beyond simple, symmetric (mirror) alignment once we start interacting. Interactions are dynamic processes, which involve continuous mutual adaptation, development of complementary behaviour and division of labour such as leader–follower roles. Here, we argue that interacting individuals are dynamically coupled rather than simply aligned. This broader framework for understanding interactions can encompass both processes by which behaviour and brain activity mirror each other (neural alignment), and situations in which behaviour and brain activity in one participant are coupled (but not mirrored) to the dynamics in the other participant. To apply these more sophisticated accounts of social interactions to the study of the underlying neural processes we need to develop new experimental paradigms and novel methods of data analysis PMID:27069044

A spatial analysis of the determinants of pneumonia and influenza hospitalizations in Ontario (1992-2001).

PubMed

Crighton, Eric J; Elliott, Susan J; Moineddin, Rahim; Kanaroglou, Pavlos; Upshur, Ross

2007-04-01

Previous research on the determinants of pneumonia and influenza has focused primarily on the role of individual level biological and behavioural risk factors resulting in partial explanations and largely curative approaches to reducing the disease burden. This study examines the geographic patterns of pneumonia and influenza hospitalizations and the role that broad ecologic-level factors may have in determining them. We conducted a county level, retrospective, ecologic study of pneumonia and influenza hospitalizations in the province of Ontario, Canada, between 1992 and 2001 (N=241,803), controlling for spatial dependence in the data. Non-spatial and spatial regression models were estimated using a range of environmental, social, economic, behavioural, and health care predictors. Results revealed low education to be positively associated with hospitalization rates over all age groups and both genders. The Aboriginal population variable was also positively associated in most models except for the 65+-year age group. Behavioural factors (daily smoking and heavy drinking), environmental factors (passive smoking, poor housing, temperature), and health care factors (influenza vaccination) were all significantly associated in different age and gender-specific models. The use of spatial error regression models allowed for unbiased estimation of regression parameters and their significance levels. These findings demonstrate the importance of broad age and gender-specific population-level factors in determining pneumonia and influenza hospitalizations, and illustrate the need for place and population-specific policies that take these factors into consideration.

Structural organisation and dynamics in king penguin colonies

NASA Astrophysics Data System (ADS)

Gerum, Richard; Richter, Sebastian; Fabry, Ben; Le Bohec, Céline; Bonadonna, Francesco; Nesterova, Anna; Zitterbart, Daniel P.

2018-04-01

During breeding, king penguins do not build nests, however they show strong territorial behaviour and keep a pecking distance to neighbouring penguins. Penguin positions in breeding colonies are highly stable over weeks and appear regularly spaced, but thus far no quantitative analysis of the structural order inside a colony has been performed. In this study, we use the radial distribution function to analyse the spatial coordinates of penguin positions. Coordinates are obtained from aerial images of two colonies that were observed for several years. Our data demonstrate that the structural order in king penguin colonies resembles a 2D liquid of particles with a Lennard-Jones-type interaction potential. We verify this using a molecular dynamics simulation with thermally driven particles, whereby temperature corresponds to penguin movements, the energy well depth ɛ of the attractive potential corresponds to the strength of the colony-forming behaviour, and the repulsive zone corresponds to the pecking radius. We can recapitulate the liquid disorder of the colony, as measured by the radial distribution function, when the particles have a temperature of several (1.4–10) \

Learning of embodied interaction dynamics with recurrent neural networks: some exploratory experiments.

PubMed

Oubbati, Mohamed; Kord, Bahram; Koprinkova-Hristova, Petia; Palm, Günther

2014-04-01

The new tendency of artificial intelligence suggests that intelligence must be seen as a result of the interaction between brains, bodies and environments. This view implies that designing sophisticated behaviour requires a primary focus on how agents are functionally coupled to their environments. Under this perspective, we present early results with the application of reservoir computing as an efficient tool to understand how behaviour emerges from interaction. Specifically, we present reservoir computing models, that are inspired by imitation learning designs, to extract the essential components of behaviour that results from agent-environment interaction dynamics. Experimental results using a mobile robot are reported to validate the learning architectures.

Learning of embodied interaction dynamics with recurrent neural networks: some exploratory experiments

NASA Astrophysics Data System (ADS)

Oubbati, Mohamed; Kord, Bahram; Koprinkova-Hristova, Petia; Palm, Günther

2014-04-01

The new tendency of artificial intelligence suggests that intelligence must be seen as a result of the interaction between brains, bodies and environments. This view implies that designing sophisticated behaviour requires a primary focus on how agents are functionally coupled to their environments. Under this perspective, we present early results with the application of reservoir computing as an efficient tool to understand how behaviour emerges from interaction. Specifically, we present reservoir computing models, that are inspired by imitation learning designs, to extract the essential components of behaviour that results from agent-environment interaction dynamics. Experimental results using a mobile robot are reported to validate the learning architectures.

A spatial socio-ecosystem approach to analyse human-environment interactions on climate change adaptation for water resources management

NASA Astrophysics Data System (ADS)

Giupponi, Carlo; Mojtahed, Vahid

2017-04-01

Global climate and socio-economic drivers determine the future patterns of the allocation and the trade of resources and commodities in all markets. The agricultural sector is an emblematic case in which natural (e.g. climate), social (e.g. demography) and economic (e.g. the market) drivers of change interact, determining the evolution of social and ecological systems (or simply socio-ecosystems; SES) over time. In order to analyse the dynamics and possible future evolutions of SES, the combination of local complex systems and global drivers and trends require the development of multiscale approaches. At global level, climatic general circulation models (CGM) and computable general equilibrium or partial equilibrium models have been used for many years to explore the effects of global trends and generate future climate and socio-economic scenarios. Al local level, the inherent complexity of SESs and their spatial and temporal variabilities require different modelling approaches of physical/environmental sub-systems (e.g. field scale crop modelling, GIS-based models, etc.) and of human agency decision makers (e.g. agent based models). Global and local models have different assumption, limitations, constrains, etc., but in some cases integration is possible and several attempts are in progress to couple different models within the so-called Integrated Assessment Models. This work explores an innovative proposal to integrate the global and local approaches, where agent-based models (ABM) are used to simulate spatial (i.e. grid-based) and temporal dynamics of land and water resource use spatial and temporal dynamics, under the effect of global drivers. We focus in particular on how global change may affect land-use allocation at the local to regional level, under the influence of limited natural resources, land and water in particular. We specifically explore how constrains and competition for natural resources may induce non-linearities and discontinuities in socio-ecosystems behaviour. Our general ambition is to explore the feasibility of an approach that could be implemented worldwide through the identification of representative cases described by means of spatially explicit integrated simulations in communication with global modelling. Our specific objective is to test how ABMs can support scenario analysis at regional scale, and in particular how this can facilitate understanding of the role of human agency and its behavioural characteristics in local to global dynamics. The SES of interest is the agro-ecosystem with its relationships with other land uses. In order to test the feasibility of application at global level, all the information about land uses, natural resources, local climate, crop potential productions, etc. were derived from freely available spatial data sets covering the whole planet, which provided the ABM model with spatial information as matrices of pixels. Input maps were extracted from the Global Agro-Ecological Zone (GAEZ) web site of the Food and Agriculture Organization of the United Nations and compiled in the local GIS from where they were then converted in a format compatible with Matlab. In this initial application, an ABM prototype was developed in three test areas around the Mediterranean Basin, in agricultural regions of Tunisia, Italy and Spain.

Slaves of the environment: the movement of herbivorous insects in relation to their ecology and genotype

PubMed Central

Loxdale, H. D.

1999-01-01

The majority of insect species do not show an innate behavioural migration, but rather populations expand into favourable new habitats or contract away from unfavourable ones by random changes of spatial scale. Over the past 50 years, the scientific fascination with dramatic long-distance and directed mass migratory events has overshadowed the more universal mode of population movement, involving much smaller stochastic displacement during the lifetime of the insects concerned. This may be limiting our understanding of insect population dynamics. In the following synthesis, we provide an overview of how herbivorous insect movement is governed by both abiotic and biotic factors, making these animals essentially 'slaves of their environment'. No displaced insect or insect population can leave a resource patch, migrate and flourish, leaving descendants, unless suitable habitat and/or resources are reached during movement. This must have constrained insects over geological time, bringing about species-specific adaptation in behaviour and movements in relation to their environment at a micro- and macrogeographical scale. With insects that undergo long-range spatial displacements, e.g. aphids and locusts, there is presumably a selection against movement unless overruled by factors, such as density-dependent triggering, which cause certain genotypes within the population to migrate. However, for most insect species, spatial changes of scale and range expansion are much slower and may occur over a much longer time-scale, and are not innate (nor directed). Ecologists may say that all animals and plants are figuratively speaking 'slaves of their environments', in the sense that their distribution is defined by their ecology and genotype. But in the case of insects, a vast number must perish daily, either out at sea or over other hostile habitats, having failed to find suitable resources and/or a habitat on which to feed and reproduce. Since many are blown by the vagaries of the wind, their chances of success are serendipitous in the extreme, especially over large distances. Hence, the strategies adopted by mass migratory species (innate pre-programmed flight behaviour, large population sizes and/or fast reproduction), which improve the chances that some of these individuals will succeed. We also emphasize the dearth of knowledge in the various interactions of insect movement and their environment, and describe how molecular markers (protein and DNA) may be used to examine the details of spatial scale over which movement occurs in relation to insect ecology and genotype.

Animal behaviour shapes the ecological effects of ocean acidification and warming: moving from individual to community-level responses.

PubMed

Nagelkerken, Ivan; Munday, Philip L

2016-03-01

Biological communities are shaped by complex interactions between organisms and their environment as well as interactions with other species. Humans are rapidly changing the marine environment through increasing greenhouse gas emissions, resulting in ocean warming and acidification. The first response by animals to environmental change is predominantly through modification of their behaviour, which in turn affects species interactions and ecological processes. Yet, many climate change studies ignore animal behaviour. Furthermore, our current knowledge of how global change alters animal behaviour is mostly restricted to single species, life phases and stressors, leading to an incomplete view of how coinciding climate stressors can affect the ecological interactions that structure biological communities. Here, we first review studies on the effects of warming and acidification on the behaviour of marine animals. We demonstrate how pervasive the effects of global change are on a wide range of critical behaviours that determine the persistence of species and their success in ecological communities. We then evaluate several approaches to studying the ecological effects of warming and acidification, and identify knowledge gaps that need to be filled, to better understand how global change will affect marine populations and communities through altered animal behaviours. Our review provides a synthesis of the far-reaching consequences that behavioural changes could have for marine ecosystems in a rapidly changing environment. Without considering the pervasive effects of climate change on animal behaviour we will limit our ability to forecast the impacts of ocean change and provide insights that can aid management strategies. © 2015 John Wiley & Sons Ltd.

Predator–prey interactions mediated by prey personality and predator hunting mode

PubMed Central

Belgrad, Benjamin A.; Griffen, Blaine D.

2016-01-01

Predator–prey interactions are important drivers in structuring ecological communities. However, despite widespread acknowledgement that individual behaviours and predator species regulate ecological processes, studies have yet to incorporate individual behavioural variations in a multipredator system. We quantified a prevalent predator avoidance behaviour to examine the simultaneous roles of prey personality and predator hunting mode in governing predator–prey interactions. Mud crabs, Panopeus herbstii, reduce their activity levels and increase their refuge use in the presence of predator cues. We measured mud crab mortality and consistent individual variations in the strength of this predator avoidance behaviour in the presence of predatory blue crabs, Callinectes sapidus, and toadfish, Opsanus tau. We found that prey personality and predator species significantly interacted to affect mortality with blue crabs primarily consuming bold mud crabs and toadfish preferentially selecting shy crabs. Additionally, the strength of the predator avoidance behaviour depended upon the predation risk from the predator species. Consequently, the personality composition of populations and predator hunting mode may be valuable predictors of both direct and indirect predator–prey interaction strength. These findings support theories postulating mechanisms for maintaining intraspecies diversity and have broad implications for community dynamics. PMID:27075257

Predator-prey interactions mediated by prey personality and predator hunting mode.

PubMed

Belgrad, Benjamin A; Griffen, Blaine D

2016-04-13

Predator-prey interactions are important drivers in structuring ecological communities. However, despite widespread acknowledgement that individual behaviours and predator species regulate ecological processes, studies have yet to incorporate individual behavioural variations in a multipredator system. We quantified a prevalent predator avoidance behaviour to examine the simultaneous roles of prey personality and predator hunting mode in governing predator-prey interactions. Mud crabs, Panopeus herbstii, reduce their activity levels and increase their refuge use in the presence of predator cues. We measured mud crab mortality and consistent individual variations in the strength of this predator avoidance behaviour in the presence of predatory blue crabs, Callinectes sapidus, and toadfish, Opsanus tau We found that prey personality and predator species significantly interacted to affect mortality with blue crabs primarily consuming bold mud crabs and toadfish preferentially selecting shy crabs. Additionally, the strength of the predator avoidance behaviour depended upon the predation risk from the predator species. Consequently, the personality composition of populations and predator hunting mode may be valuable predictors of both direct and indirect predator-prey interaction strength. These findings support theories postulating mechanisms for maintaining intraspecies diversity and have broad implications for community dynamics. © 2016 The Author(s).

Wheel-running in a transgenic mouse model of Alzheimer's disease: protection or symptom?

PubMed

Richter, Helene; Ambrée, Oliver; Lewejohann, Lars; Herring, Arne; Keyvani, Kathy; Paulus, Werner; Palme, Rupert; Touma, Chadi; Schäbitz, Wolf-Rüdiger; Sachser, Norbert

2008-06-26

Several studies on both humans and animals reveal benefits of physical exercise on brain function and health. A previous study on TgCRND8 mice, a transgenic model of Alzheimer's disease, reported beneficial effects of premorbid onset of long-term access to a running wheel on spatial learning and plaque deposition. Our study investigated the effects of access to a running wheel after the onset of Abeta pathology on behavioural, endocrinological, and neuropathological parameters. From day 80 of age, the time when Abeta deposition becomes apparent, TgCRND8 and wildtype mice were kept with or without running wheel. Home cage behaviour was analysed and cognitive abilities regarding object recognition memory and spatial learning in the Barnes maze were assessed. Our results show that, in comparison to Wt mice, Tg mice were characterised by impaired object recognition memory and spatial learning, increased glucocorticoid levels, hyperactivity in the home cage and high levels of stereotypic behaviour. Access to a running wheel had no effects on cognitive or neuropathological parameters, but reduced the amount of stereotypic behaviour in transgenics significantly. Furthermore, wheel-running was inversely correlated with stereotypic behaviour, suggesting that wheel-running may have stereotypic qualities. In addition, wheel-running positively correlated with plaque burden. Thus, in a phase when plaques are already present in the brain, it may be symptomatic of brain pathology, rather than protective. Whether or not access to a running wheel has beneficial effects on Alzheimer-like pathology and symptoms may therefore strongly depend on the exact time when the wheel is provided during development of the disease.

Parasitism, personality and cognition in fish.

PubMed

Barber, I; Mora, A B; Payne, E M; Weinersmith, K L; Sih, A

2017-08-01

It is well established that parasites can have profound effects on the behaviour of host organisms, and that individual differences in behaviour can influence susceptibility to parasite infections. Recently, two major themes of research have developed. First, there has been a growing interest in the proximate, mechanistic processes underpinning parasite-associated behaviour change, and the interactive roles of the neuro-, immune, and other physiological systems in determining relationships between behaviour and infection susceptibility. Secondly, as the study of behaviour has shifted away from one-off measurements of single behaviours and towards a behavioural syndromes/personality framework, research is starting to focus on the consequences of parasite infection for temporal and contextual consistency of behaviour, and on the implications of different personality types for infection susceptibility. In addition, there is increasing interest in the potential for relationships between cognition and personality to also have implications for host-parasite interactions. As models well-suited to both the laboratory study of behaviour and experimental parasitology, teleost fish have been used as hosts in many of these studies. In this review we provide a broad overview of the range of mechanisms that potentially generate links between fish behaviour, personality, and parasitism, and illustrate these using examples drawn from the recent literature. In addition, we examine the potential interactions between cognition, personality and parasitism, and identify questions that may be usefully investigated with fish models. Copyright © 2016 Elsevier B.V. All rights reserved.

Partial lesion of the serotonergic system by a single dose of MDMA results in behavioural disinhibition and enhances acute MDMA-induced social behaviour on the social interaction test.

PubMed

Ando, Romeo D; Benko, Anita; Ferrington, Linda; Kirilly, Eszter; Kelly, Paul A T; Bagdy, Gyorgy

2006-06-01

The acute effects of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) on anxiety-related behaviours were studied using indices of social interaction in Dark Agouti (DA) both drug naive rats and those pretreated with MDMA (15 mg/kg i.p.) 3 weeks earlier. The functional neuroanatomy of these MDMA effects was visualised using 2-deoxyglucose imaging of local cerebral glucose use (LCMRglu), whilst MDMA-induced serotonergic neurotoxicity was measured by radioligand binding with [3H]paroxetine. Acute MDMA alone markedly decreased most typical elements of social interaction but increased adjacent lying, a behaviour that also contains social elements. In animals pre-exposed to MDMA, decreased [3H]paroxetine binding indicated serotonergic terminal depletion, and in these animals significant increases in locomotor activity, exploratory behaviour and aggressive behaviour were found. Both behavioural effects and also the metabolic activation induced by acute MDMA were potentiated in rats previously exposed to the drug. In conclusion, a single dose of MDMA caused marked changes in social behaviour acutely that might be interpreted either as a decrease or increase in anxiety. Three weeks after MDMA a behavioural disinhibition similar to psychomotor agitation, a symptom connected to depression or mania, and a sensitization to the acute effects of MDMA are apparent in both the behavioural and brain metabolic effects of the drug.

High-resolution forest mapping for behavioural studies in the Nature Reserve ‘Les Nouragues’, French Guiana

PubMed Central

Ringler, Max; Mangione, Rosanna; Pašukonis, Andrius; Rainer, Gerhard; Gyimesi, Kristin; Felling, Julia; Kronaus, Hannes; Réjou-Méchain, Maxime; Chave, Jérôme; Reiter, Karl; Ringler, Eva

2015-01-01

For animals with spatially complex behaviours at relatively small scales, the resolution of a global positioning system (GPS) receiver location is often below the resolution needed to correctly map animals’ spatial behaviour. Natural conditions such as canopy cover, canyons or clouds can further degrade GPS receiver reception. Here we present a detailed, high-resolution map of a 4.6 ha Neotropical river island and a 8.3 ha mainland plot with the location of every tree >5 cm DBH and all structures on the forest floor, which are relevant to our study species, the territorial frog Allobates femoralis (Dendrobatidae). The map was derived using distance- and compass-based survey techniques, rooted on dGPS reference points, and incorporates altitudinal information based on a LiDAR survey of the area. PMID:27053943

Divergent migration within lake sturgeon (Acipenser fulvescens) populations: Multiple distinct patterns exist across an unrestricted migration corridor.

PubMed

Kessel, Steven T; Hondorp, Darryl W; Holbrook, Christopher M; Boase, James C; Chiotti, Justin A; Thomas, Michael V; Wills, Todd C; Roseman, Edward F; Drouin, Richard; Krueger, Charles C

2018-01-01

Population structure, distribution, abundance and dispersal arguably underpin the entire field of animal ecology, with consequences for regional species persistence, and provision of ecosystem services. Divergent migration behaviours among individuals or among populations are an important aspect of the ecology of highly mobile animals, allowing populations to exploit spatially or temporally distributed food and space resources. This study investigated the spatial ecology of lake sturgeon (Acipenser fulvescens) within the barrier free Huron-Erie Corridor (HEC), which connects Lake Huron and Lake Erie of the North American Laurentian Great Lakes. Over 6 years (2011-2016), movements of 268 lake sturgeon in the HEC were continuously monitored across the Great Lakes using acoustic telemetry (10 years battery life acoustic transmitters). Five distinct migration behaviours were identified with hierarchical cluster analysis, based on the phenology and duration of river and lake use. Lake sturgeon in the HEC were found to contain a high level of intraspecific divergent migration, including partial migration with the existence of residents. Specific behaviours included year-round river residency and multiple lake-migrant behaviours that involved movements between lakes and rivers. Over 85% of individuals were assigned to migration behaviours as movements were consistently repeated over the study, which suggested migration behaviours were consistent and persistent in lake sturgeon. Differential use of specific rivers or lakes by acoustic-tagged lake sturgeon further subdivided individuals into 14 "contingents" (spatiotemporally segregated subgroups). Contingents associated with one river (Detroit or St. Clair) were rarely detected in the other river, which confirmed that lake sturgeon in the Detroit and St. Clair represent two semi-independent populations that could require separate management consideration for their conservation. The distribution of migration behaviours did not vary between populations, sexes, body size or among release locations, which indicated that intrapopulation variability in migratory behaviour is a general feature of the spatial ecology of lake sturgeon in unfragmented landscapes. 2017 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

Inferring the rules of social interaction in migrating caribou.

PubMed

Torney, Colin J; Lamont, Myles; Debell, Leon; Angohiatok, Ryan J; Leclerc, Lisa-Marie; Berdahl, Andrew M

2018-05-19

Social interactions are a significant factor that influence the decision-making of species ranging from humans to bacteria. In the context of animal migration, social interactions may lead to improved decision-making, greater ability to respond to environmental cues, and the cultural transmission of optimal routes. Despite their significance, the precise nature of social interactions in migrating species remains largely unknown. Here we deploy unmanned aerial systems to collect aerial footage of caribou as they undertake their migration from Victoria Island to mainland Canada. Through a Bayesian analysis of trajectories we reveal the fine-scale interaction rules of migrating caribou and show they are attracted to one another and copy directional choices of neighbours, but do not interact through clearly defined metric or topological interaction ranges. By explicitly considering the role of social information on movement decisions we construct a map of near neighbour influence that quantifies the nature of information flow in these herds. These results will inform more realistic, mechanism-based models of migration in caribou and other social ungulates, leading to better predictions of spatial use patterns and responses to changing environmental conditions. Moreover, we anticipate that the protocol we developed here will be broadly applicable to study social behaviour in a wide range of migratory and non-migratory taxa.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Authors.

Emergent Societal Effects of Crimino-Social Forces in an Animat Agent Model

NASA Astrophysics Data System (ADS)

Scogings, Chris J.; Hawick, Ken A.

Societal behaviour can be studied at a causal level by perturbing a stable multi-agent model with new microscopic behaviours and observing the statistical response over an ensemble of simulated model systems. We report on the effects of introducing criminal and law-enforcing behaviours into a large scale animat agent model and describe the complex spatial agent patterns and population changes that result. Our well-established predator-prey substrate model provides a background framework against which these new microscopic behaviours can be trialled and investigated. We describe some quantitative results and some surprising conclusions concerning the overall societal health when individually anti-social behaviour is introduced.

Spatial Microsimulation for Rural Policy Analysis in Ireland: The Implications of CAP Reforms for the National Spatial Strategy

ERIC Educational Resources Information Center

Ballas, D.; Clarke, G. P.; Wiemers, E.

2006-01-01

Microsimulation attempts to describe economic and social events by modelling the behaviour of individual agents. These models have proved useful in evaluating the impact of policy changes at the micro level. Spatial microsimulation models contain geographic information and allow for a regional or local approach to policy analysis. This paper…

Different stability of social-communication problems and negative demanding behaviour from infancy to toddlerhood in a large Dutch population sample

PubMed Central

2014-01-01

Background Little is known about the stability of behavioural and developmental problems as children develop from infants to toddlers in the general population. Therefore, we investigated behavioural profiles at two time points and determined whether behaviours are stable during early development. Methods Parents of 4,237 children completed questionnaires with 62 items about externalizing, internalizing, and social-communicative behaviour when the children were 14–15 and 36–37 months old. Factor mixture modelling identified five homogeneous profiles at both time points: three with relatively normal behaviour or with mild/moderate problems, one with clear communication and interaction problems, and another with pronounced negative and demanding behaviour. Results More than 85% of infants with normal behaviour or mild problems at 14–15 months were reported to behave relatively typically as toddlers at 36–37 months. A similar percentage of infants with moderate communication problems outgrew their problems by the time they were toddlers. However, infants with severe problems had mild to severe problems as toddlers, and did not show completely normal behaviour. Improvement over time occurred more often in children with negative and demanding behaviour than in children with communication and interaction problems. The former showed less homotypic continuity than the latter. Conclusions Negative and demanding behaviour is more often transient and a less specific predictor of problems in toddlerhood than communication and interaction problems. PMID:25061477

Maternal communicative behaviours and interaction quality as predictors of language development: findings from a community-based study of slow-to-talk toddlers.

PubMed

Conway, Laura J; Levickis, Penny A; Smith, Jodie; Mensah, Fiona; Wake, Melissa; Reilly, Sheena

2018-03-01

Identifying risk and protective factors for language development informs interventions for children with developmental language disorder (DLD). Maternal responsive and intrusive communicative behaviours are associated with language development. Mother-child interaction quality may influence how children use these behaviours in language learning. To identify (1) communicative behaviours and interaction quality associated with language outcomes; (2) whether the association between a maternal intrusive behaviour (directive) and child language scores changed alongside a maternal responsive behaviour (expansion); and (3) whether interaction quality modified these associations. Language skills were assessed at 24, 36 and 48 months in 197 community-recruited children who were slow to talk at 18 months. Mothers and 24-month-olds were video-recorded playing at home. Maternal praise, missed opportunities, and successful and unsuccessful directives (i.e., whether followed by the child) were coded during a 10-min segment. Interaction quality was rated using a seven-point fluency and connectedness (FC) scale, during a 5-min segment. Linear regressions examined associations between these behaviours/rating and language scores. Interaction analysis and simple slopes explored effect modification by FC. There was no evidence that missed opportunities or praise were associated with language scores. Higher rates of successful directives in the unadjusted model and unsuccessful directives in the adjusted model were associated with lower 24-month-old receptive language scores (e.g., unsuccessful directives effect size (ES) = -0.41). The association between unsuccessful directives and receptive language was weaker when adjusting for co-occurring expansions (ES = -0.34). Both types of directives were associated with poorer receptive and expressive language scores in adjusted models at 36 and 48 months (e.g., unsuccessful directive and 48-month receptive language, ES = -0.66). FC was positively associated with 24-, 36- and 48-month language scores in adjusted models (e.g., receptive language at 24 months, ES = 0.21, at 48 months, ES = 0.18). Interaction analysis showed the negative association between successful directives and 24-month receptive language existed primarily in poorly connected dyads with low FC levels. These findings illustrate the effects of the combined interaction between different maternal communicative behaviours and features of the interaction itself on child language development, and the need to consider both in research and practice. Whilst more intrusive directives were associated with poorer language scores, this association attenuated when adjusting for co-occurring responsive expansions, and the association was strongest for children in lower quality interactions. This work may inform clinical practice by helping clinicians target the most appropriate communicative behaviours for specific mother-child dyads. © 2017 Royal College of Speech and Language Therapists.

A map of abstract relational knowledge in the human hippocampal–entorhinal cortex

PubMed Central

Garvert, Mona M; Dolan, Raymond J; Behrens, Timothy EJ

2017-01-01

The hippocampal–entorhinal system encodes a map of space that guides spatial navigation. Goal-directed behaviour outside of spatial navigation similarly requires a representation of abstract forms of relational knowledge. This information relies on the same neural system, but it is not known whether the organisational principles governing continuous maps may extend to the implicit encoding of discrete, non-spatial graphs. Here, we show that the human hippocampal–entorhinal system can represent relationships between objects using a metric that depends on associative strength. We reconstruct a map-like knowledge structure directly from a hippocampal–entorhinal functional magnetic resonance imaging adaptation signal in a situation where relationships are non-spatial rather than spatial, discrete rather than continuous, and unavailable to conscious awareness. Notably, the measure that best predicted a behavioural signature of implicit knowledge and blood oxygen level-dependent adaptation was a weighted sum of future states, akin to the successor representation that has been proposed to account for place and grid-cell firing patterns. DOI: http://dx.doi.org/10.7554/eLife.17086.001 PMID:28448253

Modelling engagement in dementia through behaviour. Contribution for socially interactive robotics.

PubMed

Perugia, Giulia; Diaz Doladeras, Marta; Mallofre, Andreu Catala; Rauterberg, Matthias; Barakova, Emilia

2017-07-01

In this paper, we present a novel tool to measure engagement in people with dementia playing board games and interacting with a social robot, Pleo. We carried out two studies to reach a comprehensive inventory of behaviours accounting for engagement in dementia. The first one is an exploratory study aimed at modelling engagement in cognitive board games. The second one is a longitudinal study to investigate how people with dementia express engagement in cognitive games and in interactions with social robots. We adopted a technique coming from Ethology to mould behaviour, the ethogram. Ethogram is founded on low level behaviours, and allows hierarchical structuring. Herein, we present preliminary results consisting in the description of two ethograms and in their structuring obtained through thematic analysis. Such results show that an underlying structure of engagement exists across activities, and that different activities trigger different behavioural displays of engagement that adhere to such a structure.

Interpersonal Engagement Mediates the Relation between Maternal Affect and Externalising Behaviour in Young Children with Type 1 Diabetes

PubMed Central

Chisholm, Vivienne; Gonzalez, Andrea; Atkinson, Leslie

2014-01-01

Mother-child interactions around a shared activity have been shown to play a key role in the development of young children’s capacity to interact cooperatively with others. This evidence is particularly germane to type 1 diabetes (T1D) management in younger children where cooperation with parental treatment efforts is crucial for treatment success and where maternal distress and child behavioural problems are risk factors for treatment management, biomedical and psychological outcomes. In 49 4-to-8 year old children with T1D, we investigated whether the association between maternal affect and child problematic behaviour is mediated by mother-child interactions in the context of a T1D-relevant collaborative problem-solving activity. Mothers completed standardised measures of maternal and child psychological adjustment and interacted with their children in the problem-solving activity, analysed for quality of interpersonal engagement based on evaluations of maternal (sensitivity and cognitive stimulation) and dyadic (joint attention and warmth) behaviours. Mediation analyses confirmed the hypothesis that interpersonal engagement mediates the relation between maternal affective state and child behavioural problems. Specifically, more negative maternal affect is associated with lower levels of interpersonal engagement; these less engaged interactions in turn are associated with more behavioural problems in children. These findings are consistent with research involving typically developing children. The implications of our findings are twofold. First, in the context of psychological adjustment to T1D, maternal affect and mother-child interactions are 2 potential targets for interventions which promote cooperative interactions. Second, understanding and caring for children at biological risk requires attention to developmental psychology theory and method; in particular, research addressing parent-child cooperation carries both conceptual and clinical relevance. PMID:24905358

Plasticity of spatial hearing: behavioural effects of cortical inactivation

PubMed Central

Nodal, Fernando R; Bajo, Victoria M; King, Andrew J

2012-01-01

The contribution of auditory cortex to spatial information processing was explored behaviourally in adult ferrets by reversibly deactivating different cortical areas by subdural placement of a polymer that released the GABAA agonist muscimol over a period of weeks. The spatial extent and time course of cortical inactivation were determined electrophysiologically. Muscimol-Elvax was placed bilaterally over the anterior (AEG), middle (MEG) or posterior ectosylvian gyrus (PEG), so that different regions of the auditory cortex could be deactivated in different cases. Sound localization accuracy in the horizontal plane was assessed by measuring both the initial head orienting and approach-to-target responses made by the animals. Head orienting behaviour was unaffected by silencing any region of the auditory cortex, whereas the accuracy of approach-to-target responses to brief sounds (40 ms noise bursts) was reduced by muscimol-Elvax but not by drug-free implants. Modest but significant localization impairments were observed after deactivating the MEG, AEG or PEG, although the largest deficits were produced in animals in which the MEG, where the primary auditory fields are located, was silenced. We also examined experience-induced spatial plasticity by reversibly plugging one ear. In control animals, localization accuracy for both approach-to-target and head orienting responses was initially impaired by monaural occlusion, but recovered with training over the next few days. Deactivating any part of the auditory cortex resulted in less complete recovery than in controls, with the largest deficits observed after silencing the higher-level cortical areas in the AEG and PEG. Although suggesting that each region of auditory cortex contributes to spatial learning, differences in the localization deficits and degree of adaptation between groups imply a regional specialization in the processing of spatial information across the auditory cortex. PMID:22547635

Transition from isotropic to digitated growth modulates network formation in Physarum polycephalum

NASA Astrophysics Data System (ADS)

Vogel, David; Gautrais, Jacques; Perna, Andrea; Sumpter, David J. T.; Deneubourg, Jean-Louis; Dussutour, Audrey

2017-01-01

Some organisms, including fungi, ants, and slime molds, explore their environment and forage by forming interconnected networks. The plasmodium of the slime mold Physarum polycephalum is a large unicellular amoeboid organism that grows a tubular spatial network through which nutrients, body mass, and chemical signals are transported. Individual plasmodia are capable of sophisticated behaviours such as optimizing their network connectivity and dynamics using only decentralized information processing. In this study, we used a population of plasmodia that interconnect through time to analyse the dynamical interactions between growth of individual plasmodia and global network formation. Our results showed how initial conditions, such as the distance between plasmodia, their size, or the presence and quality of food, affect the emerging network connectivity.

Navigational Strategies and Their Neural Correlates

PubMed Central

Deshmukh, Sachin S.

2018-01-01

Animals depend on navigation to find food, water, mate(s), shelter, etc. Different species use diverse strategies that utilise forms of motion- and location-related information derived from the environment to navigate to their goals and back. We start by describing behavioural studies undertaken to unearth different strategies used in navigation. Then we move on to outline what we know about the brain area most associated with spatial navigation, namely the hippocampal formation. While doing so, we first briefly explain the anatomical connections in the area and then proceed to describe the neural correlates that are considered to play a role in navigation. We conclude by looking at how the strategies might interact and complement each other in certain contexts. PMID:29657367

Coulomb engineering of the bandgap and excitons in two-dimensional materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raja, Archana; Chaves, Andrey; Yu, Jaeeun

Here, the ability to control the size of the electronic bandgap is an integral part of solid-state technology. Atomically thin two-dimensional crystals offer a new approach for tuning the energies of the electronic states based on the unusual strength of the Coulomb interaction in these materials and its environmental sensitivity. Here, we show that by engineering the surrounding dielectric environment, one can tune the electronic bandgap and the exciton binding energy in monolayers of WS 2 and WSe 2 by hundreds of meV. We exploit this behaviour to present an in-plane dielectric heterostructure with a spatially dependent bandgap, as anmore » initial step towards the creation of diverse lateral junctions with nanoscale resolution.« less

Coulomb engineering of the bandgap and excitons in two-dimensional materials

DOE PAGES

Raja, Archana; Chaves, Andrey; Yu, Jaeeun; ...

2017-05-04

Here, the ability to control the size of the electronic bandgap is an integral part of solid-state technology. Atomically thin two-dimensional crystals offer a new approach for tuning the energies of the electronic states based on the unusual strength of the Coulomb interaction in these materials and its environmental sensitivity. Here, we show that by engineering the surrounding dielectric environment, one can tune the electronic bandgap and the exciton binding energy in monolayers of WS 2 and WSe 2 by hundreds of meV. We exploit this behaviour to present an in-plane dielectric heterostructure with a spatially dependent bandgap, as anmore » initial step towards the creation of diverse lateral junctions with nanoscale resolution.« less

Scale invariance in natural and artificial collective systems: a review

PubMed Central

Huepe, Cristián

2017-01-01

Self-organized collective coordinated behaviour is an impressive phenomenon, observed in a variety of natural and artificial systems, in which coherent global structures or dynamics emerge from local interactions between individual parts. If the degree of collective integration of a system does not depend on size, its level of robustness and adaptivity is typically increased and we refer to it as scale-invariant. In this review, we first identify three main types of self-organized scale-invariant systems: scale-invariant spatial structures, scale-invariant topologies and scale-invariant dynamics. We then provide examples of scale invariance from different domains in science, describe their origins and main features and discuss potential challenges and approaches for designing and engineering artificial systems with scale-invariant properties. PMID:29093130

Coulomb engineering of the bandgap and excitons in two-dimensional materials

PubMed Central

Raja, Archana; Chaves, Andrey; Yu, Jaeeun; Arefe, Ghidewon; Hill, Heather M.; Rigosi, Albert F.; Berkelbach, Timothy C.; Nagler, Philipp; Schüller, Christian; Korn, Tobias; Nuckolls, Colin; Hone, James; Brus, Louis E.; Heinz, Tony F.; Reichman, David R.; Chernikov, Alexey

2017-01-01

The ability to control the size of the electronic bandgap is an integral part of solid-state technology. Atomically thin two-dimensional crystals offer a new approach for tuning the energies of the electronic states based on the unusual strength of the Coulomb interaction in these materials and its environmental sensitivity. Here, we show that by engineering the surrounding dielectric environment, one can tune the electronic bandgap and the exciton binding energy in monolayers of WS2 and WSe2 by hundreds of meV. We exploit this behaviour to present an in-plane dielectric heterostructure with a spatially dependent bandgap, as an initial step towards the creation of diverse lateral junctions with nanoscale resolution. PMID:28469178

De Haas-van Alphen effect of a two-dimensional ultracold atomic gas

NASA Astrophysics Data System (ADS)

Farias, B.; Furtado, C.

2016-01-01

In this paper, we show how the ultracold atom analogue of the two-dimensional de Haas-van Alphen effect in electronic condensed matter systems can be induced by optical fields in a neutral atomic system. The interaction between the suitable spatially varying laser fields and tripod-type trapped atoms generates a synthetic magnetic field which leads the particles to organize themselves in Landau levels. Initially, with the atomic gas in a regime of lowest Landau level, we display the oscillatory behaviour of the atomic energy and its derivative with respect to the effective magnetic field (B) as a function of 1/B. Furthermore, we estimate the area of the Fermi circle of the two-dimensional atomic gas.

Integrating ecology, psychology and neurobiology within a food-hoarding paradigm

PubMed Central

Pravosudov, Vladimir V.; Smulders, Tom V.

2010-01-01

Many animals regularly hoard food for future use, which appears to be an important adaptation to a seasonally and/or unpredictably changing environment. This food-hoarding paradigm is an excellent example of a natural system that has broadly influenced both theoretical and empirical work in the field of biology. The food-hoarding paradigm has played a major role in the conceptual framework of numerous fields from ecology (e.g. plant–animal interactions) and evolution (e.g. the coevolution of caching, spatial memory and the hippocampus) to psychology (e.g. memory and cognition) and neurobiology (e.g. neurogenesis and the neurobiology of learning and memory). Many food-hoarding animals retrieve caches by using spatial memory. This memory-based behavioural system has the inherent advantage of being tractable for study in both the field and laboratory and has been shaped by natural selection, which produces variation with strong fitness consequences in a variety of taxa. Thus, food hoarding is an excellent model for a highly integrative approach to understanding numerous questions across a variety of disciplines. Recently, there has been a surge of interest in the complexity of animal cognition such as future planning and episodic-like-memory as well as in the relationship between memory, the environment and the brain. In addition, new breakthroughs in neurobiology have enhanced our ability to address the mechanisms underlying these behaviours. Consequently, the field is necessarily becoming more integrative by assessing behavioural questions in the context of natural ecological systems and by addressing mechanisms through neurobiology and psychology, but, importantly, within an evolutionary and ecological framework. In this issue, we aim to bring together a series of papers providing a modern synthesis of ecology, psychology, physiology and neurobiology and identifying new directions and developments in the use of food-hoarding animals as a model system. PMID:20156812

Multi-Dimensional Analysis of Large, Complex Slope Instability: Case study of Downie Slide, British Columbia, Canada. (Invited)

NASA Astrophysics Data System (ADS)

Kalenchuk, K. S.; Hutchinson, D.; Diederichs, M. S.

2013-12-01

Downie Slide, one of the world's largest landslides, is a massive, active, composite, extremely slow rockslide located on the west bank of the Revelstoke Reservoir in British Columbia. It is a 1.5 billion m3 rockslide measuring 2400 m along the river valley, 3300m from toe to headscarp and up to 245 m thick. Significant contributions to the field of landslide geomechanics have been made by analyses of spatially and temporally discriminated slope deformations, and how these are controlled by complex geological and geotechnical factors. Downie Slide research demonstrates the importance of delineating massive landslides into morphological regions in order to characterize global slope behaviour and identify localized events, which may or may not influence the overall slope deformation patterns. Massive slope instabilities do not behave as monolithic masses, rather, different landslide zones can display specific landslide processes occurring at variable rates of deformation. The global deformation of Downie Slide is extremely slow moving; however localized regions of the slope incur moderate to high rates of movement. Complex deformation processes and composite failure mechanism are contributed to by topography, non-uniform shear surfaces, heterogeneous rockmass and shear zone strength and stiffness characteristics. Further, from the analysis of temporal changes in landslide behaviour it has been clearly recognized that different regions of the slope respond differently to changing hydrogeological boundary conditions. State-of-the-art methodologies have been developed for numerical simulation of large landslides; these provide important tools for investigating dynamic landslide systems which account for complex three-dimensional geometries, heterogenous shear zone strength parameters, internal shear zones, the interaction of discrete landslide zones and piezometric fluctuations. Numerical models of Downie Slide have been calibrated to reproduce observed slope behaviour, and the calibration process has provided important insight to key factors controlling massive slope mechanics. Through numerical studies it has been shown that the three-dimensional interpretation of basal slip surface geometry and spatial heterogeneity in shear zone stiffness are important factors controlling large-scale slope deformation processes. The role of secondary internal shears and the interaction between landslide morphological zones has also been assessed. Further, numerical simulation of changing groundwater conditions has produced reasonable correlation with field observations. Calibrated models are valuable tools for the forward prediction of landslide dynamics. Calibrated Downie Slide models have been used to investigate how trigger scenarios may accelerate deformations at Downie Slide. The ability to reproduce observed behaviour and forward test hypothesized changes to boundary conditions has valuable application in hazard management of massive landslides. The capacity of decision makers to interpret large amounts of data, respond to rapid changes in a system and understand complex slope dynamics has been enhanced.

Repeatability and consistency of individual behaviour in juvenile and adult Eurasian harvest mice

NASA Astrophysics Data System (ADS)

Schuster, Andrea C.; Carl, Teresa; Foerster, Katharina

2017-04-01

Knowledge on animal personality has provided new insights into evolutionary biology and animal ecology, as behavioural types have been shown to affect fitness. Animal personality is characterized by repeatable and consistent between-individual behavioural differences throughout time and across different situations. Behavioural repeatability within life history stages and consistency between life history stages should be checked for the independence of sex and age, as recent data have shown that males and females in some species may differ in the repeatability of behavioural traits, as well as in their consistency. We measured the repeatability and consistency of three behavioural and one cognitive traits in juvenile and adult Eurasian harvest mice ( Micromys minutus). We found that exploration, activity and boldness were repeatable in juveniles and adults. Spatial recognition measured in a Y Maze was only repeatable in adult mice. Exploration, activity and boldness were consistent before and after maturation, as well as before and after first sexual contact. Data on spatial recognition provided little evidence for consistency. Further, we found some evidence for a litter effect on behaviours by comparing different linear mixed models. We concluded that harvest mice express animal personality traits as behaviours were repeatable across sexes and consistent across life history stages. The tested cognitive trait showed low repeatability and was less consistent across life history stages. Given the rising interest in individual variation in cognitive performance, and in its relationship to animal personality, we suggest that it is important to gather more data on the repeatability and consistency of cognitive traits.

Towards a framework in interaction training for staff working with clients with intellectual disabilities and challenging behaviour.

PubMed

Willems, A; Embregts, P; Hendriks, L; Bosman, A

2016-02-01

Training support staff in dealing with challenging behaviour in clients with intellectual disabilities (ID) is needed. The goal of this study is to determine which elements need to be incorporated in a training on staff interactions with these clients, building upon a framework and an interpersonal model. As in functional analysis, this study tests the influence of client interpersonal behaviour, three types of staff reactions to challenging behaviour, two types of staff psychological resources and staff team climate on four styles of staff interpersonal behaviour. A total of 318 support staff members completed a questionnaire on staff interpersonal behaviour for 44 clients with ID and challenging behaviour, as well as seven questionnaires on client interpersonal behaviour, staff emotions, attributions, self-efficacy, self-reflection, coping styles and team climate. The influence of these seven factors on four staff interpersonal behaviours was examined using multilevel multiple regression analysis. Friendly-warm and dominant client interpersonal behaviour had a significant positive impact on friendly and assertive control staff behaviour, respectively. Also, there was a strong influence of staff negative and positive emotions, as well as their self-efficacy, on most of the staff interpersonal behaviours. Staff self-reflection, insight and avoidance-focused coping style had an impact on some staff interpersonal behaviours. Staff team climate only predicted higher support-seeking staff behaviour. In conducting a functional analysis of staff interpersonal behaviour, the results of this study can be used both as a framework in staff-client interaction training and in clinical practice for treating challenging behaviour. The emphasis in training and practice should not only be on the bidirectional dynamics of control and affiliation between staff and clients, but also - in order of importance - on the impact of staff emotions, self-efficacy, self-reflection and insight, coping style, team climate and attributions on staff interpersonal behaviour. © 2015 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

Who do you trust? The impact of facial emotion and behaviour on decision making

PubMed Central

Campellone, Timothy R.; Kring, Ann M.

2014-01-01

During social interactions, we use available information to guide our decisions, including behaviour and emotional displays. In some situations, behaviour and emotional displays may be incongruent, complicating decision making. This study had two main aims: first, to investigate the independent contributions of behaviour and facial displays of emotion on decisions to trust, and, second, to examine what happens when the information being signalled by a facial display is incongruent with behaviour. Participants played a modified version of the Trust Game in which they learned simulated players’ behaviour with or without concurrent displays of facial emotion. Results indicated that displays of anger, but not happiness, influenced decisions to trust during initial encounters. Over the course of repeated interactions, however, emotional displays consistent with an established pattern of behaviour made independent contributions to decision making, strengthening decisions to trust. When facial display and behaviour were incongruent, participants used current behaviour to inform decision making. PMID:23017055

A specific pathway can be identified between genetic characteristics and behaviour profiles in Prader-Willi syndrome via cognitive, environmental and physiological mechanisms.

PubMed

Woodcock, K A; Oliver, C; Humphreys, G W

2009-06-01

Behavioural phenotypes associated with genetic syndromes have been extensively investigated in order to generate rich descriptions of phenomenology, determine the degree of specificity of behaviours for a particular syndrome, and examine potential interactions between genetic predispositions for behaviour and environmental influences. However, relationships between different aspects of behavioural phenotypes have been less frequently researched and although recent interest in potential cognitive phenotypes or endophenotypes has increased, these are frequently studied independently of the behavioural phenotypes. Taking Prader-Willi syndrome (PWS) as an example, we discuss evidence suggesting specific relationships between apparently distinct aspects of the PWS behavioural phenotype and relate these to specific endophenotypic characteristics. The framework we describe progresses through biological, cognitive, physiological and behavioural levels to develop a pathway from genetic characteristics to behaviour with scope for interaction with the environment at any stage. We propose this multilevel approach as useful in setting out hypotheses in order to structure research that can more rapidly advance theory.

A strong genetic correlation underlying a behavioural syndrome disappears during development because of genotype–age interactions

PubMed Central

Class, Barbara; Brommer, Jon E.

2015-01-01

In animal populations, as in humans, behavioural differences between individuals that are consistent over time and across contexts are considered to reflect personality, and suites of correlated behaviours expressed by individuals are known as behavioural syndromes. Lifelong stability of behavioural syndromes is often assumed, either implicitly or explicitly. Here, we use a quantitative genetic approach to study the developmental stability of a behavioural syndrome in a wild population of blue tits. We find that a behavioural syndrome formed by a strong genetic correlation of two personality traits in nestlings disappears in adults, and we demonstrate that genotype–age interaction is the likely mechanism underlying this change during development. A behavioural syndrome may hence change during organismal development, even when personality traits seem to be strongly physiologically or functionally linked in one age group. We outline how such developmental plasticity has important ramifications for understanding the mechanistic basis as well as the evolutionary consequences of behavioural syndromes. PMID:26041348

Detecting effects of the indicated prevention Programme for Externalizing Problem behaviour (PEP) on child symptoms, parenting, and parental quality of life in a randomized controlled trial.

PubMed

Hanisch, Charlotte; Freund-Braier, Inez; Hautmann, Christopher; Jänen, Nicola; Plück, Julia; Brix, Gabriele; Eichelberger, Ilka; Döpfner, Manfred

2010-01-01

Behavioural parent training is effective in improving child disruptive behavioural problems in preschool children by increasing parenting competence. The indicated Prevention Programme for Externalizing Problem behaviour (PEP) is a group training programme for parents and kindergarten teachers of children aged 3-6 years with externalizing behavioural problems. To evaluate the effects of PEP on child problem behaviour, parenting practices, parent-child interactions, and parental quality of life. Parents and kindergarten teachers of 155 children were randomly assigned to an intervention group (n = 91) and a nontreated control group (n = 64). They rated children's problem behaviour before and after PEP training; parents also reported on their parenting practices and quality of life. Standardized play situations were video-taped and rated for parent-child interactions, e.g. parental warmth. In the intention to treat analysis, mothers of the intervention group described less disruptive child behaviour and better parenting strategies, and showed more parental warmth during a standardized parent-child interaction. Dosage analyses confirmed these results for parents who attended at least five training sessions. Children were also rated to show less behaviour problems by their kindergarten teachers. Training effects were especially positive for parents who attended at least half of the training sessions. CBCL: Child Behaviour Checklist; CII: Coder Impressions Inventory; DASS: Depression anxiety Stress Scale; HSQ: Home-situation Questionnaire; LSS: Life Satisfaction Scale; OBDT: observed behaviour during the test; PCL: Problem Checklist; PEP: prevention programme for externalizing problem behaviour; PPC: Parent Problem Checklist; PPS: Parent Practices Scale; PS: Parenting Scale; PSBC: Problem Setting and Behaviour checklist; QJPS: Questionnaire on Judging Parental Strains; SEFS: Self-Efficacy Scale; SSC: Social Support Scale; TRF: Caregiver-Teacher Report Form.

Ecohydrology and tipping points in semiarid australian rangelands

NASA Astrophysics Data System (ADS)

Saco, P. M.; Azadi, S.; Moreno de las Heras, M.; Willgoose, G. R.

2017-12-01

Semiarid landscapes are often characterised by a spatially heterogeneous vegetation cover forming mosaics of patches with dense vegetation within bare soil. This patchy vegetation cover, which is linked to the healthy function of these ecosystems, is sensitive to human disturbances that can lead to degradation. Previous work suggests that vegetation loss below a critical value can lead to a sudden decrease in landscape functionality following threshold behaviour. The decrease in vegetation cover is linked to erosion and substantial water losses by increasing landscape hydrological connectivity. We study these interactions and the possible existence of tipping points in the Mulga land bioregion, by combining remote sensing observations and results from an eco-geomorphologic model to investigate changes in ecosystem connectivity and the existence of threshold behaviour. More than 30 sites were selected along a precipitation gradient spanning a range from approximately 250 to 500 mm annual rainfall. The analysis of vegetation patterns is derived from high resolution remote sensing images (IKONOS, QuickBird, Pleiades) and MODIS NDVI, which combined with local precipitation data is used to compute rainfall use efficiency to assess the ecosystem function. A critical tipping point associated to loss of vegetation cover appears in the sites with lower annual precipitation. We found that this tipping point behaviour decreases for sites with higher rainfall. We use the model to investigate the relation between structural and functional connectivity and the emergence of threshold behaviour for selected plots along this precipitation gradient. Both observations and modelling results suggest that sites with higher rainfall are more resilient to changes in surface connectivity. The implications for ecosystem resilience and land management are discussed

Using probability modelling and genetic parentage assignment to test the role of local mate availability in mating system variation.

PubMed

Blyton, Michaela D J; Banks, Sam C; Peakall, Rod; Lindenmayer, David B

2012-02-01

The formal testing of mating system theories with empirical data is important for evaluating the relative importance of different processes in shaping mating systems in wild populations. Here, we present a generally applicable probability modelling framework to test the role of local mate availability in determining a population's level of genetic monogamy. We provide a significance test for detecting departures in observed mating patterns from model expectations based on mate availability alone, allowing the presence and direction of behavioural effects to be inferred. The assessment of mate availability can be flexible and in this study it was based on population density, sex ratio and spatial arrangement. This approach provides a useful tool for (1) isolating the effect of mate availability in variable mating systems and (2) in combination with genetic parentage analyses, gaining insights into the nature of mating behaviours in elusive species. To illustrate this modelling approach, we have applied it to investigate the variable mating system of the mountain brushtail possum (Trichosurus cunninghami) and compared the model expectations with the outcomes of genetic parentage analysis over an 18-year study. The observed level of monogamy was higher than predicted under the model. Thus, behavioural traits, such as mate guarding or selective mate choice, may increase the population level of monogamy. We show that combining genetic parentage data with probability modelling can facilitate an improved understanding of the complex interactions between behavioural adaptations and demographic dynamics in driving mating system variation. © 2011 Blackwell Publishing Ltd.

Interaction effects in the theory of planned behaviour: Predicting fruit and vegetable consumption in three prospective cohorts.

PubMed

Kothe, Emily J; Mullan, Barbara A

2015-09-01

The theory of planned behaviour (TPB) has been criticized for not including interactions between major constructs thought to underlie behaviour. This study investigated the application of the TPB to the prediction of fruit and vegetable consumption across three prospective cohorts. The primary aim of the study was to investigate whether interactions between major constructs in the theory would increase the ability of the model to predict intention to consume fruit and vegetables (i.e., attitude × perceived behavioural control [PBC], subjective norm × PBC, subjective norm × attitude) and self-reported fruit and vegetable intake (i.e., PBC × intention). Secondary data analysis from three cohorts: One predictive study (cohort 1) and two intervention studies (cohorts 2 and 3). Participants completed a TPB measure at baseline and a measure of fruit and vegetable intake at 1 week (cohort 1; n = 90) or 1 month (cohorts 2 and 3; n = 296). Attitude moderated the impact of PBC on intention. PBC moderated the impact of intention on behaviour at 1 week but not 1 month. The variance accounted for by the interactions was small. However, the presence of interactions between constructs within the TPB demonstrates a need to consider interactions between variables within the TPB in both theoretical and applied research using the model. © 2014 The British Psychological Society.

Preliminary evidence that abscisic acid improves spatial memory in rats.

PubMed

Qi, Cong-Cong; Ge, Jin-Fang; Zhou, Jiang-Ning

2015-02-01

Abscisic acid (ABA) is a crucial phytohormone that exists in a wide range of animals, including humans, and has multiple bioactivities. As direct derivatives of carotenoids, ABA and retinoic acid (RA) share similar molecular structures, and RA has been reported to improve spatial memory in rodents. To explore the potential effects of ABA on spatial learning and memory in rodents, 20mg/kg ABA was administered to young rats for 6weeks, and its effects on behaviour performance were evaluated through a series of behavioural tests. ABA pharmacokinetic analysis revealed that the exogenous ABA was distributed widely in the rat brain, characterised by rapid absorption and slow elimination. The behavioural tests showed that ABA increased both the duration spent in the target quadrant and the frequency it was entered in the probe test of the Morris water maze (MWM) and decreased the latency to locate the target quadrant. Moreover, ABA decreased the latency to enter the novel arm in the Y-maze test, accompanied by increases in the total entries and distance travelled in the three arms. However, there were no significant differences between the ABA-treated and control rats in the open field test and elevated plus-maze test. These results preliminarily indicate that ABA improves spatial memory in MWM and exploratory activity in Y-maze in young rats. Copyright © 2014 Elsevier Inc. All rights reserved.

Mechanosensory Interactions Drive Collective Behaviour in Drosophila

PubMed Central

Ramdya, Pavan; Lichocki, Pawel; Cruchet, Steeve; Frisch, Lukas; Tse, Winnie; Floreano, Dario; Benton, Richard

2014-01-01

Collective behaviour enhances environmental sensing and decision-making in groups of animals1,2. Experimental and theoretical investigations of schooling fish, flocking birds and human crowds have demonstrated that simple interactions between individuals can explain emergent group dynamics3,4. These findings imply the existence of neural circuits that support distributed behaviours, but the molecular and cellular identities of relevant sensory pathways are unknown. Here we show that Drosophila melanogaster exhibits collective responses to an aversive odour: individual flies weakly avoid the stimulus, but groups show enhanced escape reactions. Using high-resolution behavioural tracking, computational simulations, genetic perturbations, neural silencing and optogenetic activation we demonstrate that this collective odour avoidance arises from cascades of appendage touch interactions between pairs of flies. Inter-fly touch sensing and collective behaviour require the activity of distal leg mechanosensory sensilla neurons and the mechanosensory channel NOMPC5,6. Remarkably, through these inter-fly encounters, wild-type flies can elicit avoidance behaviour in mutant animals that cannot sense the odour – a basic form of communication. Our data highlight the unexpected importance of social context in the sensory responses of a solitary species and open the door to a neural circuit level understanding of collective behaviour in animal groups. PMID:25533959

Non-verbal communication in meetings of psychiatrists and patients with schizophrenia.

PubMed

Lavelle, M; Dimic, S; Wildgrube, C; McCabe, R; Priebe, S

2015-03-01

Recent evidence found that patients with schizophrenia display non-verbal behaviour designed to avoid social engagement during the opening moments of their meetings with psychiatrists. This study aimed to replicate, and build on, this finding, assessing the non-verbal behaviour of patients and psychiatrists during meetings, exploring changes over time and its association with patients' symptoms and the quality of the therapeutic relationship. 40-videotaped routine out-patient consultations, involving patients with schizophrenia, were analysed. Non-verbal behaviour of patients and psychiatrists was assessed during three fixed, 2-min intervals using a modified Ethological Coding System for Interviews. Symptoms, satisfaction with communication and the quality of the therapeutic relationship were also measured. Over time, patients' non-verbal behaviour remained stable, whilst psychiatrists' flight behaviour decreased. Patients formed two groups based on their non-verbal profiles, one group (n = 25) displaying pro-social behaviour, inviting interaction and a second (n = 15) displaying flight behaviour, avoiding interaction. Psychiatrists interacting with pro-social patients displayed more pro-social behaviours (P < 0.001). Patients' pro-social profile was associated reduced symptom severity (P < 0.05), greater satisfaction with communication (P < 0.001) and positive therapeutic relationships (P < 0.05). Patients' non-verbal behaviour during routine psychiatric consultations remains unchanged, and is linked to both their psychiatrist's non-verbal behaviour and the quality of the therapeutic relationship. © 2014 The Authors. Acta Psychiatrica Scandinavica Published by John Wiley & Sons Ltd.

Projecting changes in the distribution and productivity of living marine resources: A critical review of the suite of modelling approaches used in the large European project VECTORS

NASA Astrophysics Data System (ADS)

Peck, Myron A.; Arvanitidis, Christos; Butenschön, Momme; Canu, Donata Melaku; Chatzinikolaou, Eva; Cucco, Andrea; Domenici, Paolo; Fernandes, Jose A.; Gasche, Loic; Huebert, Klaus B.; Hufnagl, Marc; Jones, Miranda C.; Kempf, Alexander; Keyl, Friedemann; Maar, Marie; Mahévas, Stéphanie; Marchal, Paul; Nicolas, Delphine; Pinnegar, John K.; Rivot, Etienne; Rochette, Sébastien; Sell, Anne F.; Sinerchia, Matteo; Solidoro, Cosimo; Somerfield, Paul J.; Teal, Lorna R.; Travers-Trolet, Morgan; van de Wolfshaar, Karen E.

2018-02-01

We review and compare four broad categories of spatially-explicit modelling approaches currently used to understand and project changes in the distribution and productivity of living marine resources including: 1) statistical species distribution models, 2) physiology-based, biophysical models of single life stages or the whole life cycle of species, 3) food web models, and 4) end-to-end models. Single pressures are rare and, in the future, models must be able to examine multiple factors affecting living marine resources such as interactions between: i) climate-driven changes in temperature regimes and acidification, ii) reductions in water quality due to eutrophication, iii) the introduction of alien invasive species, and/or iv) (over-)exploitation by fisheries. Statistical (correlative) approaches can be used to detect historical patterns which may not be relevant in the future. Advancing predictive capacity of changes in distribution and productivity of living marine resources requires explicit modelling of biological and physical mechanisms. New formulations are needed which (depending on the question) will need to strive for more realism in ecophysiology and behaviour of individuals, life history strategies of species, as well as trophodynamic interactions occurring at different spatial scales. Coupling existing models (e.g. physical, biological, economic) is one avenue that has proven successful. However, fundamental advancements are needed to address key issues such as the adaptive capacity of species/groups and ecosystems. The continued development of end-to-end models (e.g., physics to fish to human sectors) will be critical if we hope to assess how multiple pressures may interact to cause changes in living marine resources including the ecological and economic costs and trade-offs of different spatial management strategies. Given the strengths and weaknesses of the various types of models reviewed here, confidence in projections of changes in the distribution and productivity of living marine resources will be increased by assessing model structural uncertainty through biological ensemble modelling.

Stereo vision for ecohydraulic research: Seashell reconstruction

NASA Astrophysics Data System (ADS)

Friedrich, H.; Bertin, S.; Montgomery, J. C.; Thrush, S. F.; Delmas, P.

2016-12-01

3D information of underwater topographies can be obtained more easily nowadays. In general, those measurements do not provide the spatial nor temporal detail for more specific research of dynamic processes, such as sediment transport. More recently, we have seen the advance of true interdisciplinary ecohydraulics research initiatives. One important research avenue is the interaction of organisms with flow and sediment. We have used stereo vision substantially for fluvial morphology studies over the last years, and will present and discuss the use of stereo vision in ecohydraulic research. The work is undertaken in the laboratory, and we present a workflow of reconstructing seashells. We obtain shape and dimensional information, which are important to better understand the organism's interaction in the natural water environment. Although we find that stereo vision is suitable to capture our studied organisms, the challenge of studying organisms in their natural environments persists. We discuss the limitations of our approach, and the need to fuse technical and behavioural knowledge to better manage our ecosystems.

Enhanced spin-phonon-electronic coupling in a 5d oxide

DOE PAGES

Calder, Stuart A.; Yamaura, K.; Tsujimoto, Y.; ...

2015-11-26

Enhanced coupling of material properties offers new fundamental insights and routes to multifunctional devices. In this context 5d oxides provide new paradigms of cooperative interactions that drive novel emergent behaviour. This is exemplified in osmates that host metal insulator transitions where magnetic order appears intimately entwined. Here we consider such a material, the 5d perovskite NaOsO 3, and observe a coupling between spin and phonon manifested in a frequency shift of 40 cm 1, the largest measured in any material. The anomalous modes are shown to involve solely Os O interactions and magnetism is revealed as the driving microscopic mechanismmore » for the phonon renormalization. The magnitude of the coupling in NaOsO 3 is primarily due to a property common to all 5d materials: the large spatial extent of the ion. This allows magnetism to couple to phonons on an unprecedented scale and in general offers multiple new routes to enhanced coupled phenomena in 5d materials.« less

New insights into the multi-scale climatic drivers of the "Karakoram anomaly"

NASA Astrophysics Data System (ADS)

Collier, S.; Moelg, T.; Nicholson, L. I.; Maussion, F.; Scherer, D.; Bush, A. B.

2012-12-01

Glacier behaviour in the Karakoram region of the northwestern Himalaya shows strong spatial and temporal heterogeneity and, in some basins, anomalous trends compared with glaciers elsewhere in High Asia. Our knowledge of the mass balance fluctuations of Karakoram glaciers as well as of the important driving factors and interactions between them is limited by a scarcity of in-situ measurements and other studies. Here we employ a novel approach to simulating atmosphere-cryosphere interactions - coupled high-resolution atmospheric and physically-based surface mass balance modelling - to examine the surface energy and mass fluxes of glaciers in this region. We discuss the mesoscale climatic drivers behind surface mass balance fluctuations as well as the influence of local forcing factors, such as debris cover and feedbacks from the glacier surface to the atmosphere. The coupled modelling approach therefore provides an innovative, multi-scale solution to the paucity of information we have to date on the much-debated "Karakoram anomaly."

Dynamic density functional theory with hydrodynamic interactions: theoretical development and application in the study of phase separation in gas-liquid systems.

PubMed

Kikkinides, E S; Monson, P A

2015-03-07

Building on recent developments in dynamic density functional theory, we have developed a version of the theory that includes hydrodynamic interactions. This is achieved by combining the continuity and momentum equations eliminating velocity fields, so the resulting model equation contains only terms related to the fluid density and its time and spatial derivatives. The new model satisfies simultaneously continuity and momentum equations under the assumptions of constant dynamic or kinematic viscosity and small velocities and/or density gradients. We present applications of the theory to spinodal decomposition of subcritical temperatures for one-dimensional and three-dimensional density perturbations for both a van der Waals fluid and for a lattice gas model in mean field theory. In the latter case, the theory provides a hydrodynamic extension to the recently studied dynamic mean field theory. We find that the theory correctly describes the transition from diffusive phase separation at short times to hydrodynamic behaviour at long times.

Dynamic density functional theory with hydrodynamic interactions: Theoretical development and application in the study of phase separation in gas-liquid systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kikkinides, E. S.; Monson, P. A.

Building on recent developments in dynamic density functional theory, we have developed a version of the theory that includes hydrodynamic interactions. This is achieved by combining the continuity and momentum equations eliminating velocity fields, so the resulting model equation contains only terms related to the fluid density and its time and spatial derivatives. The new model satisfies simultaneously continuity and momentum equations under the assumptions of constant dynamic or kinematic viscosity and small velocities and/or density gradients. We present applications of the theory to spinodal decomposition of subcritical temperatures for one-dimensional and three-dimensional density perturbations for both a van dermore » Waals fluid and for a lattice gas model in mean field theory. In the latter case, the theory provides a hydrodynamic extension to the recently studied dynamic mean field theory. We find that the theory correctly describes the transition from diffusive phase separation at short times to hydrodynamic behaviour at long times.« less

The Relation between Intrapersonal and Interpersonal Staff Behaviour towards Clients with ID and Challenging Behaviour: A Validation Study of the Staff-Client Interactive Behaviour Inventory

ERIC Educational Resources Information Center

Willems, A. P. A. M.; Embregts, P. J. C. M.; Stams, G. J. J. M.; Moonen, X. M. H.

2010-01-01

Background: Interpersonal staff behaviour is one of the instigating factors associated with challenging behaviour in clients with intellectual disabilities (ID). There are several studies focusing on the influence of intrapersonal staff characteristics--such as beliefs, attributions and emotional reactions--on staff behaviour. Little is known,…

Staff Variables Associated with the Challenging Behaviour of Clients with Severe or Profound Intellectual Disabilities

ERIC Educational Resources Information Center

Lambrechts, G.; Kuppens, S.; Maes, B.

2009-01-01

Background: Previous research has identified that staff-client interactions play an important role in the origin and maintenance of challenging behaviour. Particularly, the reciprocity between staff behaviour and client behaviour has been considered a key issue. Furthermore, severe challenging behaviour has been found to elicit negative emotional…

Emotion, working memory task demands and individual differences predict behavior, cognitive effort and negative affect.

PubMed

Storbeck, Justin; Davidson, Nicole A; Dahl, Chelsea F; Blass, Sara; Yung, Edwin

2015-01-01

We examined whether positive and negative affect motivates verbal and spatial working memory processes, respectively, which have implications for the expenditure of mental effort. We argue that when emotion promotes cognitive tendencies that are goal incompatible with task demands, greater cognitive effort is required to perform well. We sought to investigate whether this increase in cognitive effort impairs behavioural control over a broad domain of self-control tasks. Moreover, we predicted that individuals with higher behavioural inhibition system (BIS) sensitivities would report more negative affect within the goal incompatible conditions because such individuals report higher negative affect during cognitive challenge. Positive or negative affective states were induced followed by completing a verbal or spatial 2-back working memory task. All participants then completed one of three self-control tasks. Overall, we observed that conditions of emotion and working memory incompatibility (positive/spatial and negative/verbal) performed worse on the self-control tasks, and within the incompatible conditions individuals with higher BIS sensitivities reported more negative affect at the end of the study. The combination of findings suggests that emotion and working memory compatibility reduces cognitive effort and impairs behavioural control.

Spatial location in brief, free-viewing face encoding modulates contextual face recognition

PubMed Central

Felisberti, Fatima M.; McDermott, Mark R.

2013-01-01

The effect of the spatial location of faces in the visual field during brief, free-viewing encoding in subsequent face recognition is not known. This study addressed this question by tagging three groups of faces with cheating, cooperating or neutral behaviours and presenting them for encoding in two visual hemifields (upper vs. lower or left vs. right). Participants then had to indicate if a centrally presented face had been seen before or not. Head and eye movements were free in all phases. Findings showed that the overall recognition of cooperators was significantly better than cheaters, and it was better for faces encoded in the upper hemifield than in the lower hemifield, both in terms of a higher d′ and faster reaction time (RT). The d′ for any given behaviour in the left and right hemifields was similar. The RT in the left hemifield did not vary with tagged behaviour, whereas the RT in the right hemifield was longer for cheaters than for cooperators. The results showed that memory biases in contextual face recognition were modulated by the spatial location of briefly encoded faces and are discussed in terms of scanning reading habits, top-left bias in lighting preference and peripersonal space. PMID:24349694

Biological influences on inter- and intraspecific isotopic variability among paired chondrostome fishes.

PubMed

Durbec, Martial; The, Bénédicte Nguyen; Grey, Jonathan; Harrod, Christopher; Stolzenberg, Nicolas; Chappaz, Rémi; Cavalli, Laurent

2010-08-01

This study aimed at examining resource partitioning both at the inter- and intraspecific levels between paired chondrostome fishes: Chondrostoma nasus, the nase, C. toxostoma, the sofie, and their hybrid. The study was performed in the south of France and concerned a main river (the Durance River) and a tributary (the Buech River). In these rivers, C. nasus was an introduced species, originating in central Europe, and C. toxostoma was an endemic congener, in the south of France. Stable isotope analysis was used to analyse trophic and spatial niches. Isotopic differences indicated that individuals from the three taxa (C. nasus, C. toxostoma and their hybrid) have different spatial origins. At the interspecific level, the different chondrostomes originating from the Buech River showed a high level of trophic niche overlap. At the intraspecific level, nase individuals originating from the different spatial origins showed a resource polymorphism; differences in morphology were associated with variation in behaviour and life history traits. Their coexistence was a likely outcome of resource polymorphism. This study provides an example of the importance of considering the link between intra- and interspecific interactions to gain an understanding of the mechanisms driving the coexistence of species-pairs. Copyright 2010 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Accounting for Negative Automaintenance in Pigeons: A Dual Learning Systems Approach and Factored Representations

PubMed Central

Lesaint, Florian; Sigaud, Olivier; Khamassi, Mehdi

2014-01-01

Animals, including Humans, are prone to develop persistent maladaptive and suboptimal behaviours. Some of these behaviours have been suggested to arise from interactions between brain systems of Pavlovian conditioning, the acquisition of responses to initially neutral stimuli previously paired with rewards, and instrumental conditioning, the acquisition of active behaviours leading to rewards. However the mechanics of these systems and their interactions are still unclear. While extensively studied independently, few models have been developed to account for these interactions. On some experiment, pigeons have been observed to display a maladaptive behaviour that some suggest to involve conflicts between Pavlovian and instrumental conditioning. In a procedure referred as negative automaintenance, a key light is paired with the subsequent delivery of food, however any peck towards the key light results in the omission of the reward. Studies showed that in such procedure some pigeons persisted in pecking to a substantial level despite its negative consequence, while others learned to refrain from pecking and maximized their cumulative rewards. Furthermore, the pigeons that were unable to refrain from pecking could nevertheless shift their pecks towards a harmless alternative key light. We confronted a computational model that combines dual-learning systems and factored representations, recently developed to account for sign-tracking and goal-tracking behaviours in rats, to these negative automaintenance experimental data. We show that it can explain the variability of the observed behaviours and the capacity of alternative key lights to distract pigeons from their detrimental behaviours. These results confirm the proposed model as an interesting tool to reproduce experiments that could involve interactions between Pavlovian and instrumental conditioning. The model allows us to draw predictions that may be experimentally verified, which could help further investigate the neural mechanisms underlying theses interactions. PMID:25347531

Influence of the rotor-stator interaction on the dynamic stresses of Francis runners

NASA Astrophysics Data System (ADS)

Guillaume, R.; Deniau, J. L.; Scolaro, D.; Colombet, C.

2012-11-01

Thanks to advances in computing capabilities and Computational Fluid Dynamics (CFD) techniques, it is now possible to calculate realistic unsteady pressure fields in Francis turbines. This paper will explain methods to calculate the structural loads and the dynamic behaviour in order to optimize the turbine design and maximize its reliability and lifetime. Depending on the operating conditions of a Francis turbine, different hydraulic phenomena may impact the mechanical behaviour of the structure. According to their nature, these highly variable phenomena should be treated differently and specifically in order to estimate the potential risks arising on submerged structures, in particular the runner. The operating condition studied thereafter is the point at maximum power with the maximum head. Under this condition, the runner is excited by only one dynamic phenomenon named the Rotor-Stator Interaction (RSI). The origin of the phenomenon is located on the radial gap of the turbine and is the source of pressure fluctuations. A fluid-structure analysis is performed to observe the influence of that dynamic pressure field on the runner behaviour. The first part of the paper deals with the unsteady fluid computation. The RSI phenomenon is totally unsteady so the fluid simulation must take into account the entire machine and its rotation movement, in order to obtain a dynamic pressure field. In the second part of the paper, a method suitable for the RSI study is developed. It is known that the fluctuating pressure in this gap can be described as a sum of spatial components. By evaluating these components in the CFD results and on the scale model, it is possible to assess the relevance of the numerical results on the whole runner. After this step, the numerical pressure field can be used as the dynamic load of the structure. The final part of the paper presentsthe mechanical finite element calculations. A modal analysis of the runner in water and a harmonic analysis of its dynamic behaviour using the CFD results are carried out. These calculations will show that the RSI on the medium head Francis runner does not create damage on the runner even if the natural frequencies are closed to the wicket gates passing frequency. The numerical results are reinforced by experimental observations done on runner prototypes showing that the wicket gates passing frequency does not have significant influence on low and medium head Francis runner behaviour.

Visual adaptation dominates bimodal visual-motor action adaptation

PubMed Central

de la Rosa, Stephan; Ferstl, Ylva; Bülthoff, Heinrich H.

2016-01-01

A long standing debate revolves around the question whether visual action recognition primarily relies on visual or motor action information. Previous studies mainly examined the contribution of either visual or motor information to action recognition. Yet, the interaction of visual and motor action information is particularly important for understanding action recognition in social interactions, where humans often observe and execute actions at the same time. Here, we behaviourally examined the interaction of visual and motor action recognition processes when participants simultaneously observe and execute actions. We took advantage of behavioural action adaptation effects to investigate behavioural correlates of neural action recognition mechanisms. In line with previous results, we find that prolonged visual exposure (visual adaptation) and prolonged execution of the same action with closed eyes (non-visual motor adaptation) influence action recognition. However, when participants simultaneously adapted visually and motorically – akin to simultaneous execution and observation of actions in social interactions - adaptation effects were only modulated by visual but not motor adaptation. Action recognition, therefore, relies primarily on vision-based action recognition mechanisms in situations that require simultaneous action observation and execution, such as social interactions. The results suggest caution when associating social behaviour in social interactions with motor based information. PMID:27029781

A Framework for Spatial Interaction Analysis Based on Large-Scale Mobile Phone Data

PubMed Central

Li, Weifeng; Cheng, Xiaoyun; Guo, Gaohua

2014-01-01

The overall understanding of spatial interaction and the exact knowledge of its dynamic evolution are required in the urban planning and transportation planning. This study aimed to analyze the spatial interaction based on the large-scale mobile phone data. The newly arisen mass dataset required a new methodology which was compatible with its peculiar characteristics. A three-stage framework was proposed in this paper, including data preprocessing, critical activity identification, and spatial interaction measurement. The proposed framework introduced the frequent pattern mining and measured the spatial interaction by the obtained association. A case study of three communities in Shanghai was carried out as verification of proposed method and demonstration of its practical application. The spatial interaction patterns and the representative features proved the rationality of the proposed framework. PMID:25435865

To be so bold: boldness is repeatable and related to within individual behavioural variability in North Island robins.

PubMed

He, Ruchuan; Pagani-Núñez, Emilio; Chevallier, Clément; Barnett, Craig R A

2017-07-01

Behavioural research traditionally focusses on the mean responses of a group of individuals rather than variation in behaviour around the mean or among individuals. However, examining the variation in behaviour among and within individuals may also yield important insights into the evolution and maintenance of behaviour. Repeatability is the most commonly used measure of variability among individuals in behavioural research. However, there are other forms of variation within populations that have received less attention. One such measure is intraindividual variation in behaviour (IIV), which is a short-term fluctuation of within-individual behaviour. Such variation in behaviour might be important during interactions because it could decrease the ability of conspecific and heterospecific individuals to predict the behaviour of the subject, thus increasing the cost of the interaction. In this experiment, we made repeated measures of the latency of North Island robins to attack a prey in a novel situation (a form of boldness) and examined (i) repeatability of boldness (the propensity to take a risk), (ii) IIV of boldness, and (iii) whether there was a significant relationship between these two traits (a behavioural syndrome). We found that boldness was highly repeatable, that there were high levels of IIV in boldness, and that there was a negative relationship between boldness and IIV in boldness. This suggests that despite high levels of repeatability for this behaviour, there were also still significant differences in IIV among different individuals within the population. Moreover, bolder individuals had significantly less IIV in their boldness, which suggests that they were forming routines (which reduces behavioural variability) compared to shyer individuals. Our results definitively demonstrate that IIV itself varies across individuals and is linked with key behavioural traits, and we argue for the importance of future studies aimed at understanding its causes and consequences for behavioural interactions. Copyright © 2017 Elsevier B.V. All rights reserved.

FIND: difFerential chromatin INteractions Detection using a spatial Poisson process

PubMed Central

Chen, Yang; Zhang, Michael Q.

2018-01-01

Polymer-based simulations and experimental studies indicate the existence of a spatial dependency between the adjacent DNA fibers involved in the formation of chromatin loops. However, the existing strategies for detecting differential chromatin interactions assume that the interacting segments are spatially independent from the other segments nearby. To resolve this issue, we developed a new computational method, FIND, which considers the local spatial dependency between interacting loci. FIND uses a spatial Poisson process to detect differential chromatin interactions that show a significant difference in their interaction frequency and the interaction frequency of their neighbors. Simulation and biological data analysis show that FIND outperforms the widely used count-based methods and has a better signal-to-noise ratio. PMID:29440282

Modeling Warfare in Social Animals: A "Chemical" Approach

PubMed Central

Santarlasci, Alisa; Martelloni, Gianluca; Frizzi, Filippo; Santini, Giacomo; Bagnoli, Franco

2014-01-01

We present here a general method for modelling the dynamics of battles among social animals. The proposed method exploits the procedures widely used to model chemical reactions, but still uncommon in behavioural studies. We applied this methodology to the interpretation of experimental observations of battles between two species of ants (Lasius neglectus and Lasius paralienus), but this scheme may have a wider applicability and can be extended to other species as well. We performed two types of experiment labelled as interaction and mortality. The interaction experiments are designed to obtain information on the combat dynamics and lasted one hour. The mortality ones provide information on the casualty rates of the two species and lasted five hours. We modelled the interactions among ants using a chemical model which considers the single ant individuals and fighting groups analogously to atoms and molecules. The mean-field behaviour of the model is described by a set of non-linear differential equations. We also performed stochastic simulations of the corresponding agent-based model by means of the Gillespie event-driven integration scheme. By fitting the stochastic trajectories with the deterministic model, we obtained the probability distribution of the reaction parameters. The main result that we obtained is a dominance phase diagram, that gives the average trajectory of a generic battle, for an arbitrary number of opponents. This phase diagram was validated with some extra experiments. With respect to other war models (e.g., Lanchester's ones), our chemical model considers all phases of the battle and not only casualties. This allows a more detailed description of the battle (with a larger number of parameters), allowing the development of more sophisticated models (e.g., spatial ones), with the goal of distinguishing collective effects from the strategic ones. PMID:25369269

Modeling warfare in social animals: a "chemical" approach.

PubMed

Santarlasci, Alisa; Martelloni, Gianluca; Frizzi, Filippo; Santini, Giacomo; Bagnoli, Franco

2014-01-01

We present here a general method for modelling the dynamics of battles among social animals. The proposed method exploits the procedures widely used to model chemical reactions, but still uncommon in behavioural studies. We applied this methodology to the interpretation of experimental observations of battles between two species of ants (Lasius neglectus and Lasius paralienus), but this scheme may have a wider applicability and can be extended to other species as well. We performed two types of experiment labelled as interaction and mortality. The interaction experiments are designed to obtain information on the combat dynamics and lasted one hour. The mortality ones provide information on the casualty rates of the two species and lasted five hours. We modelled the interactions among ants using a chemical model which considers the single ant individuals and fighting groups analogously to atoms and molecules. The mean-field behaviour of the model is described by a set of non-linear differential equations. We also performed stochastic simulations of the corresponding agent-based model by means of the Gillespie event-driven integration scheme. By fitting the stochastic trajectories with the deterministic model, we obtained the probability distribution of the reaction parameters. The main result that we obtained is a dominance phase diagram, that gives the average trajectory of a generic battle, for an arbitrary number of opponents. This phase diagram was validated with some extra experiments. With respect to other war models (e.g., Lanchester's ones), our chemical model considers all phases of the battle and not only casualties. This allows a more detailed description of the battle (with a larger number of parameters), allowing the development of more sophisticated models (e.g., spatial ones), with the goal of distinguishing collective effects from the strategic ones.

Measuring directional urban spatial interaction in China: A migration perspective

PubMed Central

Li, Fangzhou; Feng, Zhiming; Li, Peng; You, Zhen

2017-01-01

The study of urban spatial interaction is closely linked to that of economic geography, urban planning, regional development, and so on. Currently, this topic is generating a great deal of interest among researchers who are striving to find accurate ways to measure urban spatial interaction. Classical spatial interaction models lack theoretical guidance and require complicated parameter-adjusting processes. The radiation model, however, as proposed by Simini et al. with rigorous formula derivation, can simulate directional urban spatial interaction. We applied the radiation model in China to simulate the directional migration number among 337 nationwide research units, comprising 4 municipalities and 333 prefecture-level cities. We then analyzed the overall situation in Chinese cities, the interaction intensity hierarchy, and the prime urban agglomerations from the perspective of migration. This was done to ascertain China’s urban spatial interaction and regional development from 2000 to 2010 to reveal ground realities. PMID:28141853

Measuring directional urban spatial interaction in China: A migration perspective.

PubMed

Li, Fangzhou; Feng, Zhiming; Li, Peng; You, Zhen

2017-01-01

The study of urban spatial interaction is closely linked to that of economic geography, urban planning, regional development, and so on. Currently, this topic is generating a great deal of interest among researchers who are striving to find accurate ways to measure urban spatial interaction. Classical spatial interaction models lack theoretical guidance and require complicated parameter-adjusting processes. The radiation model, however, as proposed by Simini et al. with rigorous formula derivation, can simulate directional urban spatial interaction. We applied the radiation model in China to simulate the directional migration number among 337 nationwide research units, comprising 4 municipalities and 333 prefecture-level cities. We then analyzed the overall situation in Chinese cities, the interaction intensity hierarchy, and the prime urban agglomerations from the perspective of migration. This was done to ascertain China's urban spatial interaction and regional development from 2000 to 2010 to reveal ground realities.

Mule deer spatial association patterns and potential implications for transmission of an epizootic disease.

PubMed

Mejía-Salazar, María Fernanda; Goldizen, Anne W; Menz, Clementine S; Dwyer, Ross G; Blomberg, Simon P; Waldner, Cheryl L; Cullingham, Catherine I; Bollinger, Trent K

2017-01-01

Animal social behaviour can have important effects on the long-term dynamics of diseases. In particular, preferential spatial relationships between individuals can lead to differences in the rates of disease spread within a population. We examined the concurrent influence of genetic relatedness, sex, age, home range overlap, time of year, and prion disease status on proximal associations of adult Rocky Mountain mule deer (Odocoileus hemionus hemionus) in a chronic wasting disease endemic area. We also quantified the temporal stability of these associations across different sex, age, and disease status classes. We used three years of high frequency telemetry data from 74 individuals to record encounters within 25 m of each other, and to calculate seasonal home range overlap measured by volume of intersection (VI). The strength of pairwise spatial association between adult mule deer was independent of genetic relatedness, age and disease status. Seasonal variation in association strength was not consistent across years, perhaps due to annual changes in weather conditions. The influence of home range overlap on association strength varied seasonally, whereby associations were stronger in pre-rut and fawning than in the rest of the seasons. The sexes of individuals also interacted with both VI and season. At increasing levels of VI, associations were stronger between females than between males and between females and males. The strongest associations in pre-rut were between males, while the strongest in rut were between females and males. The temporal stability of associations was markedly dependant on the sex and the diagnosis of the associating pair. Our findings highlight the importance of considering concurrent effects of biological and environmental factors when seeking to understand the role of social preference in behavioural ecology and disease spread. Applying this knowledge in epidemiological modelling will shed light on the dynamics of disease transmission among mule deer.

Mule deer spatial association patterns and potential implications for transmission of an epizootic disease

PubMed Central

Goldizen, Anne W.; Menz, Clementine S.; Dwyer, Ross G.; Blomberg, Simon P.; Waldner, Cheryl L.; Cullingham, Catherine I.; Bollinger, Trent K.

2017-01-01

Animal social behaviour can have important effects on the long-term dynamics of diseases. In particular, preferential spatial relationships between individuals can lead to differences in the rates of disease spread within a population. We examined the concurrent influence of genetic relatedness, sex, age, home range overlap, time of year, and prion disease status on proximal associations of adult Rocky Mountain mule deer (Odocoileus hemionus hemionus) in a chronic wasting disease endemic area. We also quantified the temporal stability of these associations across different sex, age, and disease status classes. We used three years of high frequency telemetry data from 74 individuals to record encounters within 25 m of each other, and to calculate seasonal home range overlap measured by volume of intersection (VI). The strength of pairwise spatial association between adult mule deer was independent of genetic relatedness, age and disease status. Seasonal variation in association strength was not consistent across years, perhaps due to annual changes in weather conditions. The influence of home range overlap on association strength varied seasonally, whereby associations were stronger in pre-rut and fawning than in the rest of the seasons. The sexes of individuals also interacted with both VI and season. At increasing levels of VI, associations were stronger between females than between males and between females and males. The strongest associations in pre-rut were between males, while the strongest in rut were between females and males. The temporal stability of associations was markedly dependant on the sex and the diagnosis of the associating pair. Our findings highlight the importance of considering concurrent effects of biological and environmental factors when seeking to understand the role of social preference in behavioural ecology and disease spread. Applying this knowledge in epidemiological modelling will shed light on the dynamics of disease transmission among mule deer. PMID:28388681

Numerical Modelling of Fire-Atmosphere Interactions and the 2003 Canberra Bushfires

NASA Astrophysics Data System (ADS)

Simpson, C.; Sturman, A.; Zawar-Reza, P.

2010-12-01

It is well known that the behaviour of a wildland fire is strongly associated with the conditions of its surrounding atmosphere. However, the two-way interactions between fire behaviour and the atmospheric conditions are not well understood. A numerical model is used to simulate wildland fires so that the nature of these fire-atmosphere interactions, and how they might affect fire behaviour, can be further investigated. The 2003 Canberra bushfires are used as a case study due to their highly destructive and unusual behaviour. On the 18th January 2003, these fires spread to the urban suburbs of Canberra, resulting in the loss of four lives and the destruction of over 500 homes. Fire-atmosphere interactions are believed to have played an important role in making these fires so destructive. WRF-Fire is used to perform real data simulations of the 2003 Canberra bushfires. WRF-Fire is a coupled fire-atmosphere model, which combines a semi-empirical fire spread model with an atmospheric model, allowing it to directly simulate the two-way interactions between a fire and its surrounding atmosphere. These simulations show the impact of the presence of a fire on conditions within the atmospheric boundary layer. This modification of the atmosphere, resulting from the injection of heat and moisture released by the fire, appears to have a direct feedback onto the overall fire behaviour. The bushfire simulations presented in this paper provide important scientific insights into the nature of fire-atmosphere interactions for a real situation. It is expected that they will also help fire managers in Australia to better understand why the 2003 Canberra bushfires were so destructive, as well as to gain improved insight into bushfire behaviour in general.

Vast assembly of vocal marine mammals from diverse species on fish spawning ground.

PubMed

Wang, Delin; Garcia, Heriberto; Huang, Wei; Tran, Duong D; Jain, Ankita D; Yi, Dong Hoon; Gong, Zheng; Jech, J Michael; Godø, Olav Rune; Makris, Nicholas C; Ratilal, Purnima

2016-03-17

Observing marine mammal (MM) populations continuously in time and space over the immense ocean areas they inhabit is challenging but essential for gathering an unambiguous record of their distribution, as well as understanding their behaviour and interaction with prey species. Here we use passive ocean acoustic waveguide remote sensing (POAWRS) in an important North Atlantic feeding ground to instantaneously detect, localize and classify MM vocalizations from diverse species over an approximately 100,000 km(2) region. More than eight species of vocal MMs are found to spatially converge on fish spawning areas containing massive densely populated herring shoals at night-time and diffuse herring distributions during daytime. We find the vocal MMs divide the enormous fish prey field into species-specific foraging areas with varying degrees of spatial overlap, maintained for at least two weeks of the herring spawning period. The recorded vocalization rates are diel (24 h)-dependent for all MM species, with some significantly more vocal at night and others more vocal during the day. The four key baleen whale species of the region: fin, humpback, blue and minke have vocalization rate trends that are highly correlated to trends in fish shoaling density and to each other over the diel cycle. These results reveal the temporospatial dynamics of combined multi-species MM foraging activities in the vicinity of an extensive fish prey field that forms a massive ecological hotspot, and would be unattainable with conventional methodologies. Understanding MM behaviour and distributions is essential for management of marine ecosystems and for accessing anthropogenic impacts on these protected marine species.

Paths and patterns: the biology and physics of swimming bacterial populations

NASA Technical Reports Server (NTRS)

Kessler, J. O.; Strittmatter, R. P.; Swartz, D. L.; Wiseley, D. A.; Wojciechowski, M. F.

1995-01-01

The velocity distribution of swimming micro-organisms depends on directional cues supplied by the environment. Directional swimming within a bounded space results in the accumulation of organisms near one or more surfaces. Gravity, gradients of chemical concentration and illumination affect the motile behaviour of individual swimmers. Concentrated populations of organisms scatter and absorb light or consume molecules, such as oxygen. When supply is one-sided, consumption creates gradients; the presence of the population alters the intensity and the symmetry of the environmental cues. Patterns of cues interact dynamically with patterns of the consumer population. In suspensions, spatial variations in the concentration of organisms are equivalent to variations of mean mass density of the fluid. When organisms accumulate in one region whilst moving away from another region, the force of gravity causes convection that translocates both organisms and dissolved substances. The geometry of the resulting concentration-convection patterns has features that are remarkably reproducible. Of interest for biology are (1) the long-range organisation achieved by organisms that do not communicate, and (2) that the entire system, consisting of fluid, cells, directional supply of consumables, boundaries and gravity, generates a dynamic that improves the organisms' habitat by enhancing transport and mixing. Velocity distributions of the bacterium Bacillus subtilis have been measured within the milieu of the spatially and temporally varying oxygen concentration which they themselves create. These distributions of swimming speed and direction are the fundamental ingredients required for a quantitative mathematical treatment of the patterns. The quantitative measurement of swimming behaviour also contributes to our understanding of aerotaxis of individual cells.

Quantum-mechanical elaboration for the description of low- and high-order harmonics generated by extended gas media: prospects to the efficiency enhancement in spatially modulated media

NASA Astrophysics Data System (ADS)

Stremoukhov, Sergey Yu; Andreev, Anatoly V.

2018-03-01

A simple model fully matching the description of the low- and high-order harmonic generation in extended media interacting with multicolor laser fields is proposed. The extended atomic media is modeled by a 1D chain of atoms, the number of atoms and the distance between them depend on the pressure of the gas and the length of the gas cell. The response of the individual atoms is calculated accurately in the frame of the non-perturbative theory where the driving field for each atom is calculated with account of dispersion properties of any multicolor field component. In spite of the simplicity of the proposed model it provides the detailed description of behaviour of harmonic spectra under variation of the gas pressure and medium length, it also predicts a scaling law for harmonic generation (an invariant). To demonstrate the wide range of applications of the model we have simulated the results of recent experiments dealing with spatially modulated media and obtained good coincidence between the numerical results and the experimental ones.

The interplay between human population dynamics and flooding in Bangladesh: a spatial analysis

NASA Astrophysics Data System (ADS)

di Baldassarre, G.; Yan, K.; Ferdous, MD. R.; Brandimarte, L.

2014-09-01

In Bangladesh, socio-economic and hydrological processes are both extremely dynamic and inter-related. Human population patterns are often explained as a response, or adaptation strategy, to physical events, e.g. flooding, salt-water intrusion, and erosion. Meanwhile, these physical processes are exacerbated, or mitigated, by diverse human interventions, e.g. river diversion, levees and polders. In this context, this paper describes an attempt to explore the complex interplay between floods and societies in Bangladeshi floodplains. In particular, we performed a spatially-distributed analysis of the interactions between the dynamics of human settlements and flood inundation patterns. To this end, we used flooding simulation results from inundation modelling, LISFLOOD-FP, as well as global datasets of population distribution data, such as the Gridded Population of the World (20 years, from 1990 to 2010) and HYDE datasets (310 years, from 1700 to 2010). The outcomes of this work highlight the behaviour of Bangladeshi floodplains as complex human-water systems and indicate the need to go beyond the traditional narratives based on one-way cause-effects, e.g. climate change leading to migrations.

Examining Associations of Environmental Characteristics with Recreational Cycling Behaviour by Street-Level Strava Data

PubMed Central

Sun, Yeran; Du, Yunyan; Wang, Yu; Zhuang, Liyuan

2017-01-01

Policymakers pay much attention to effectively increasing frequency of people’s cycling in the context of developing sustainable and green cities. Investigating associations of environmental characteristics and cycling behaviour could offer implications for changing urban infrastructure aiming at encouraging active travel. However, earlier examinations of associations between environmental characteristics and active travel behaviour are limited by low spatial granularity and coverage of traditional data. Crowdsourced geographic information offers an opportunity to determine the fine-grained travel patterns of people. Particularly, Strava Metro data offer a good opportunity for studies of recreational cycling behaviour as they can offer hourly, daily or annual cycling volumes with different purposes (commuting or recreational) in each street across a city. Therefore, in this study, we utilised Strava Metro data for investigating associations between environmental characteristics and recreational cycling behaviour at a large spatial scale (street level). In this study, we took account of population density, employment density, road length, road connectivity, proximity to public transit services, land use mix, proximity to green space, volume of motor vehicles and traffic accidents in an empirical investigation over Glasgow. Empirical results reveal that Strava cyclists are more likely to cycle for recreation on streets with short length, large connectivity or low volume of motor vehicles or on streets surrounded by residential land. PMID:28617345

Examining Associations of Environmental Characteristics with Recreational Cycling Behaviour by Street-Level Strava Data.

PubMed

Sun, Yeran; Du, Yunyan; Wang, Yu; Zhuang, Liyuan

2017-06-15

Policymakers pay much attention to effectively increasing frequency of people's cycling in the context of developing sustainable and green cities. Investigating associations of environmental characteristics and cycling behaviour could offer implications for changing urban infrastructure aiming at encouraging active travel. However, earlier examinations of associations between environmental characteristics and active travel behaviour are limited by low spatial granularity and coverage of traditional data. Crowdsourced geographic information offers an opportunity to determine the fine-grained travel patterns of people. Particularly, Strava Metro data offer a good opportunity for studies of recreational cycling behaviour as they can offer hourly, daily or annual cycling volumes with different purposes (commuting or recreational) in each street across a city. Therefore, in this study, we utilised Strava Metro data for investigating associations between environmental characteristics and recreational cycling behaviour at a large spatial scale (street level). In this study, we took account of population density, employment density, road length, road connectivity, proximity to public transit services, land use mix, proximity to green space, volume of motor vehicles and traffic accidents in an empirical investigation over Glasgow. Empirical results reveal that Strava cyclists are more likely to cycle for recreation on streets with short length, large connectivity or low volume of motor vehicles or on streets surrounded by residential land.

Encouraging Spatial Talk: Using Children's Museums to Bolster Spatial Reasoning

ERIC Educational Resources Information Center

Polinsky, Naomi; Perez, Jasmin; Grehl, Mora; McCrink, Koleen

2017-01-01

Longitudinal spatial language intervention studies have shown that greater exposure to spatial language improves children's performance on spatial tasks. Can short naturalistic, spatial language interactions also evoke improved spatial performance? In this study, parents were asked to interact with their child at a block wall exhibit in a…

a Multidisciplinary Analytical Framework for Studying Active Mobility Patterns

NASA Astrophysics Data System (ADS)

Orellana, D.; Hermida, C.; Osorio, P.

2016-06-01

Intermediate cities are urged to change and adapt their mobility systems from a high energy-demanding motorized model to a sustainable low-motorized model. In order to accomplish such a model, city administrations need to better understand active mobility patterns and their links to socio-demographic and cultural aspects of the population. During the last decade, researchers have demonstrated the potential of geo-location technologies and mobile devices to gather massive amounts of data for mobility studies. However, the analysis and interpretation of this data has been carried out by specialized research groups with relatively narrow approaches from different disciplines. Consequently, broader questions remain less explored, mainly those relating to spatial behaviour of individuals and populations with their geographic environment and the motivations and perceptions shaping such behaviour. Understanding sustainable mobility and exploring new research paths require an interdisciplinary approach given the complex nature of mobility systems and their social, economic and environmental impacts. Here, we introduce the elements for a multidisciplinary analytical framework for studying active mobility patterns comprised of three components: a) Methodological, b) Behavioural, and c) Perceptual. We demonstrate the applicability of the framework by analysing mobility patterns of cyclists and pedestrians in an intermediate city integrating a range of techniques, including: GPS tracking, spatial analysis, auto-ethnography, and perceptual mapping. The results demonstrated the existence of non-evident spatial behaviours and how perceptual features affect mobility. This knowledge is useful for developing policies and practices for sustainable mobility planning.

Spatial forms and mental imagery.

PubMed

Price, Mark C

2009-01-01

Four studies investigated how general mental imagery might be involved in mediating the phenomenon of 'synaesthetic' spatial forms - i.e., the experience that sequences such as months or numbers have spatial locations. In Study 1, people with spatial forms scored higher than controls on visual imagery self-report scales. This is consistent with the suggestion that strong general imagery is at least a necessary condition to experience spatial forms. However self-reported spatial imagery did not differ between groups, suggesting either that the spatial nature of forms is mediated by special synaesthetic mechanisms, or that forms are depictive visual images rather than explicit spatial models. A methodological implication of Study 1 was that a general tendency for people with spatial forms to use imagery strategies might account for some of their previously-reported behavioural differences with control groups. This concern was supported by Studies 2-4. Normal participants were encouraged to visually image the months in various spatial layouts, and spatial associations for months were tested using left/right key presses to classify month names as belonging to the first or second half of the year (Studies 2-3) or as odd/even (Study 4). Reaction times showed month-SNARC (Spatial Numerical Association of Response Codes) effects of similar magnitude to previously-reported data from spatial form participants (Price and Mentzoni, 2008). Additionally, reversing the spatial associations within instructed images was sufficient to reverse the direction of observed month-SNARC effects (i.e., positive vs negative slope), just as different spatial forms were previously shown to modulate the direction of effects (ibid.). Results challenge whether previously observed behavioural differences between spatial form and control groups need to be explained in terms of special synaesthetic mechanisms rather than intentional imagery strategies. It is argued that usually strong general imagery processes should complement synaesthetic mechanisms as possible explanations of spatial forms.

Mind-mindedness and maternal responsiveness in infant-mother interactions in mothers with severe mental illness.

PubMed

Pawlby, S; Fernyhough, C; Meins, E; Pariante, C M; Seneviratne, G; Bentall, R P

2010-11-01

Previous cross-diagnosis studies of interaction between mothers with severe mental illness and their babies have concluded that mothers with schizophrenia have deficits in interaction, but these studies have not included healthy controls. In-patients on a mother and baby unit, with diagnoses of schizophrenia (n=15), depressive mood disorders with or without psychosis (n=23), or mood disorders where mania was the predominant feature, with or without psychosis (n=12), were observed interacting with their infants on admission and discharge. Mothers' mind-mindedness and other measures of the quality of maternal and infant behaviour were coded. Findings from this sample were compared with those from healthy mothers and their infants (n=49). Compared with healthy controls, on admission depressed mothers were marginally less likely to comment appropriately on their infants' mental states. Both the depressed and mania groups were more likely to touch their babies and engage in attention-seeking behaviours. Interactional behaviours of mothers in the schizophrenia group were not markedly different from healthy controls. On discharge there were fewer differences between the clinical and healthy groups, although the depressed group continued to engage in more attention-seeking and touching behaviour and the mania group continued to touch their infants more. Only mothers in the schizophrenia group showed changes in interactional behaviours between admission and discharge, talking more to their infants. The findings challenge previous conclusions that mothers with schizophrenia have deficits in their interactions with their babies, and demonstrate that mothers with severe mental illness are able to respond appropriately to their infants' cues.

The three-body problem with short-range interactions

NASA Astrophysics Data System (ADS)

Nielsen, E.; Fedorov, D. V.; Jensen, A. S.; Garrido, E.

2001-06-01

The quantum mechanical three-body problem is studied for general short-range interactions. We work in coordinate space to facilitate accurate computations of weakly bound and spatially extended systems. Hyperspherical coordinates are used in both the interpretation and as an integral part of the numerical method. Universal properties and model independence are discussed throughout the report. We present an overview of the hyperspherical adiabatic Faddeev equations. The wave function is expanded on hyperspherical angular eigenfunctions which in turn are found numerically using the Faddeev equations. We generalize the formalism to any dimension of space d greater or equal to two. We present two numerical techniques for solving the Faddeev equations on the hypersphere. These techniques are effective for short and intermediate/large distances including use for hard core repulsive potentials. We study the asymptotic limit of large hyperradius and derive the analytic behaviour of the angular eigenvalues and eigenfunctions. We discuss four applications of the general method. We first analyze the Efimov and Thomas effects for arbitrary angular momenta and for arbitrary dimensions d. Second we apply the method to extract the general behaviour of weakly bound three-body systems in two dimensions. Third we illustrate the method in three dimensions by structure computations of Borromean halo nuclei, the hypertriton and helium molecules. Fourth we investigate in three dimensions three-body continuum properties of Borromean halo nuclei and recombination reactions of helium atoms as an example of direct relevance for the stability of Bose-Einstein condensates.

Selective Coupling between Theta Phase and Neocortical Fast Gamma Oscillations during REM-Sleep in Mice

PubMed Central

Scheffzük, Claudia; Kukushka, Valeriy I.; Vyssotski, Alexei L.; Draguhn, Andreas

2011-01-01

Background The mammalian brain expresses a wide range of state-dependent network oscillations which vary in frequency and spatial extension. Such rhythms can entrain multiple neurons into coherent patterns of activity, consistent with a role in behaviour, cognition and memory formation. Recent evidence suggests that locally generated fast network oscillations can be systematically aligned to long-range slow oscillations. It is likely that such cross-frequency coupling supports specific tasks including behavioural choice and working memory. Principal Findings We analyzed temporal coupling between high-frequency oscillations and EEG theta activity (4–12 Hz) in recordings from mouse parietal neocortex. Theta was exclusively present during active wakefulness and REM-sleep. Fast oscillations occurred in two separate frequency bands: gamma (40–100 Hz) and fast gamma (120–160 Hz). Theta, gamma and fast gamma were more prominent during active wakefulness as compared to REM-sleep. Coupling between theta and the two types of fast oscillations, however, was more pronounced during REM-sleep. This state-dependent cross-frequency coupling was particularly strong for theta-fast gamma interaction which increased 9-fold during REM as compared to active wakefulness. Theta-gamma coupling increased only by 1.5-fold. Significance State-dependent cross-frequency-coupling provides a new functional characteristic of REM-sleep and establishes a unique property of neocortical fast gamma oscillations. Interactions between defined patterns of slow and fast network oscillations may serve selective functions in sleep-dependent information processing. PMID:22163023

Early gestational exposure to moderate concentrations of ethanol alters adult behaviour in C57BL/6J mice.

PubMed

Sanchez Vega, Michelle C; Chong, Suyinn; Burne, Thomas H J

2013-09-01

Alcohol consumption during pregnancy has deleterious effects on the developing foetus ranging from subtle physical deficits to severe behavioural abnormalities and is encompassed under a broad umbrella term, foetal alcohol spectrum disorders (FASD). High levels of exposure show distinct effects, whereas the consequences of moderate exposures have been less well studied. The aim of this study was to examine the effects of a moderate dose ethanol exposure using an ad libitum drinking procedure during the first eight days of gestation in mice on the behavioural phenotype of adult offspring. Adult female C57Bl/6J mice were mated and exposed to either 10% (v/v) ethanol or water for the first 8 days of gestation (GD 0-8), and then offered water for the rest of gestation. Early developmental milestone achievement was assessed in offspring at postnatal days (P) 7, 14 and 21. Adult offspring underwent a comprehensive battery of behavioural tests to examine a range of behavioural domains including locomotion, exploration, anxiety, social behaviour, learned helplessness, sensorimotor gating, and nociception, as well as spatial memory in a water maze. Ethanol-exposed mice had similar postnatal developmental trajectories to water-exposed mice. However, the ethanol-exposed mice showed increased hyperlocomotion at P 14, 21 and 70 (p<0.05). Increased exploration and heightened motivation were also observed in adult mice. Furthermore, ethanol-exposed mice showed a significant improvement in memory in the water maze. The main findings were that mice had persistent and long lasting alterations in behaviour, including hyperactivity and enhanced spatial memory. These data suggest that even moderate dose ethanol exposure in early gestation has long term consequences on brain function and behaviour in mice. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Nutrition information-seeking behaviour of low-income pregnant Maghrebian women.

PubMed

Legault, Anik; Marquis, Marie

2014-01-01

Nutrition information-seeking behaviour was explored among low-income pregnant Maghrebian women living in Montreal. Environmental factors likely to influence nutrition information-seeking behaviour during pregnancy are discussed. Data were collected in face-to-face interviews with 14 primigravid pregnant women recruited via the Montreal Diet Dispensary, a nonprofit agency with the mission of promoting health among low-income pregnant women. Data collection was part of a larger project on pregnant women's nutrition decision-making. Environmental factors likely to influence information-seeking behaviour were identified. They were grouped within two major themes: culture and interactions with individuals from the social environment. The culture theme was divided into three minor themes: eating habits, food beliefs, and religious beliefs. The interactions with individuals from the social environment theme was divided into two minor themes: interactions with health care providers and interactions with family members. Understanding the influence of these environmental factors should help registered dietitians tailor communication strategies to pregnant immigrant women's specific information needs.

Spatial variability of surface fuels in treated and untreated ponderosa pine forests of the southern Rocky Mountains

Treesearch

Emma Vakili; Chad M. Hoffman; Robert E. Keane; Wade T. Tinkham; Yvette Dickinson

2016-01-01

There is growing consensus that spatial variability in fuel loading at scales down to 0.5 m may govern fire behaviour and effects. However, there remains a lack of understanding of how fuels vary through space in wildland settings. This study quantifies surface fuel loading and its spatial variability in ponderosa pine sites before and after fuels treatment in the...

Parent-child interaction: Does parental language matter?

PubMed

Menashe, Atara; Atzaba-Poria, Naama

2016-11-01

Although parental language and behaviour have been widely investigated, few studies have examined their unique and interactive contribution to the parent-child relationship. The current study explores how parental behaviour (sensitivity and non-intrusiveness) and the use of parental language (exploring and control languages) correlate with parent-child dyadic mutuality. Specifically, we investigated the following questions: (1) 'Is parental language associated with parent-child dyadic mutuality above and beyond parental behaviour?' (2) 'Does parental language moderate the links between parental behaviour and the parent-child dyadic mutuality?' (3) 'Do these differences vary between mothers and fathers?' The sample included 65 children (M age  = 1.97 years, SD = 0.86) and their parents. We observed parental behaviour, parent-child dyadic mutuality, and the type of parental language used during videotaped in-home observations. The results indicated that parental language and behaviours are distinct components of the parent-child interaction. Parents who used higher levels of exploring language showed higher levels of parent-child dyadic mutuality, even when accounting for parental behaviour. Use of controlling language, however, was not found to be related to the parent-child dyadic mutuality. Different moderation models were found for mothers and fathers. These results highlight the need to distinguish parental language and behaviour when assessing their contribution to the parent-child relationship. © 2016 The British Psychological Society.

Foetal Testosterone, Social Relationships, and Restricted Interests in Children

ERIC Educational Resources Information Center

Knickmeyer, Rebecca; Baron-Cohen, Simon; Raggatt, Peter; Taylor, Kevin

2005-01-01

Background: Sex-differences exist in some areas of human social behaviour. In animals, foetal testosterone (fT) plays a central role in organising the brain and in later social behaviour. fT has also been implicated in language development, eye-contact, and spatial ability in humans. Methods: Fifty-eight children (35 male and 23 female), whose fT…

The multidimensional behavioural hypervolumes of two interacting species predict their space use and survival

PubMed Central

Lichtenstein, James L. L.; Wright, Colin M; McEwen, Brendan; Pinter-Wollman, Noa; Pruitt, Jonathan N.

2018-01-01

Individual animals differ consistently in their behaviour, thus impacting a wide variety of ecological outcomes. Recent advances in animal personality research have established the ecological importance of the multidimensional behavioural volume occupied by individuals and by multispecies communities. Here, we examine the degree to which the multidimensional behavioural volume of a group predicts the outcome of both intra- and interspecific interactions. In particular, we test the hypothesis that a population of conspecifics will experience low intraspecific competition when the population occupies a large volume in behavioural space. We further hypothesize that populations of interacting species will exhibit greater interspecific competition when one or both species occupy large volumes in behavioural space. We evaluate these hypotheses by studying groups of katydids (Scudderia nymphs) and froghoppers (Philaenus spumarius), which compete for food and space on their shared host plant, Solidago canadensis. We found that individuals in single-species groups of katydids positioned themselves closer to one another, suggesting reduced competition, when groups occupied a large behavioural volume. When both species were placed together, we found that the survival of froghoppers was greatest when both froghoppers and katydids occupied a small volume in behavioural space, particularly at high froghopper densities. These results suggest that groups that occupy large behavioural volumes can have low intraspecific competition but high interspecific competition. Thus, behavioural hypervolumes appear to have ecological consequences at both the level of the population and the community and may help to predict the intensity of competition both within and across species. PMID:29681647

Insights into a spatially embedded social network from a large-scale snowball sample

NASA Astrophysics Data System (ADS)

Illenberger, J.; Kowald, M.; Axhausen, K. W.; Nagel, K.

2011-12-01

Much research has been conducted to obtain insights into the basic laws governing human travel behaviour. While the traditional travel survey has been for a long time the main source of travel data, recent approaches to use GPS data, mobile phone data, or the circulation of bank notes as a proxy for human travel behaviour are promising. The present study proposes a further source of such proxy-data: the social network. We collect data using an innovative snowball sampling technique to obtain details on the structure of a leisure-contacts network. We analyse the network with respect to its topology, the individuals' characteristics, and its spatial structure. We further show that a multiplication of the functions describing the spatial distribution of leisure contacts and the frequency of physical contacts results in a trip distribution that is consistent with data from the Swiss travel survey.

FIND: difFerential chromatin INteractions Detection using a spatial Poisson process.

PubMed

Djekidel, Mohamed Nadhir; Chen, Yang; Zhang, Michael Q

2018-02-12

Polymer-based simulations and experimental studies indicate the existence of a spatial dependency between the adjacent DNA fibers involved in the formation of chromatin loops. However, the existing strategies for detecting differential chromatin interactions assume that the interacting segments are spatially independent from the other segments nearby. To resolve this issue, we developed a new computational method, FIND, which considers the local spatial dependency between interacting loci. FIND uses a spatial Poisson process to detect differential chromatin interactions that show a significant difference in their interaction frequency and the interaction frequency of their neighbors. Simulation and biological data analysis show that FIND outperforms the widely used count-based methods and has a better signal-to-noise ratio. © 2018 Djekidel et al.; Published by Cold Spring Harbor Laboratory Press.

Physiological State Influences the Social Interactions of Two Honeybee Nest Mates

PubMed Central

Wright, Geraldine A.; Lillvis, Joshua L.; Bray, Helen J.; Mustard, Julie A.

2012-01-01

Physiological state profoundly influences the expression of the behaviour of individuals and can affect social interactions between animals. How physiological state influences food sharing and social behaviour in social insects is poorly understood. Here, we examined the social interactions and food sharing behaviour of honeybees with the aim of developing the honeybee as a model for understanding how an individual's state influences its social interactions. The state of individual honeybees was manipulated by either starving donor bees or feeding them sucrose or low doses of ethanol to examine how a change in hunger or inebriation state affected the social behaviours exhibited by two closely-related nestmates. Using a lab-based assay for measuring individual motor behaviour and social behaviour, we found that behaviours such as antennation, willingness to engage in trophallaxis, and mandible opening were affected by both hunger and ethanol intoxication. Inebriated bees were more likely to exhibit mandible opening, which may represent a form of aggression, than bees fed sucrose alone. However, intoxicated bees were as willing to engage in trophallaxis as the sucrose-fed bees. The effects of ethanol on social behaviors were dose-dependent, with higher doses of ethanol producing larger effects on behaviour. Hungry donor bees, on the other hand, were more likely to engage in begging for food and less likely to antennate and to display mandible opening. We also found that when nestmates received food from donors previously fed ethanol, they began to display evidence of inebriation, indicating that ethanol can be retained in the crop for several hours and that it can be transferred between honeybee nestmates during trophallaxis. PMID:22427864

Differential impact of student behaviours on group interaction and collaborative learning: medical students' and tutors' perspectives.

PubMed

Iqbal, Maha; Velan, Gary M; O'Sullivan, Anthony J; Balasooriya, Chinthaka

2016-08-22

Collaboration is of increasing importance in medical education and medical practice. Students' and tutors' perceptions about small group learning are valuable to inform the development of strategies to promote group dynamics and collaborative learning. This study investigated medical students' and tutors' views on competencies and behaviours which promote effective learning and interaction in small group settings. This study was conducted at UNSW Australia. Five focus group discussions were conducted with first and second year medical students and eight small group tutors were interviewed. Data were transcribed verbatim and thematic analysis was conducted. Students and tutors identified a range of behaviours that influenced collaborative learning. The main themes that emerged included: respectfulness; dominance, strong opinions and openness; constructiveness of feedback; active listening and contribution; goal orientation; acceptance of roles and responsibilities; engagement and enthusiasm; preparedness; self- awareness and positive personal attributes. An important finding was that some of these student behaviours were found to have a differential impact on group interaction compared with collaborative learning. This information could be used to promote higher quality learning in small groups. This study has identified medical students' and tutors' perceptions regarding interactional behaviours in small groups, as well as behaviours which lead to more effective learning in those settings. This information could be used to promote learning in small groups.

Increasing Responsive Parent–Child Interactions and Joint Engagement: Comparing the Influence of Parent-Mediated Intervention and Parent Psychoeducation

PubMed Central

Gulsrud, Amanda; Kasari, Connie

2016-01-01

Enhancing immediate and contingent responding by caregivers to children’s signals is an important strategy to support social interactions between caregivers and their children with autism. Yet, there has been limited examination of parents’ responsive behaviour in association with children’s social behaviour post caregiver-mediated intervention. Eighty-five dyads were randomized to one of two 10-week caregiver-training interventions. Parent–child play interactions were coded for parental responsivity and children’s joint engagement. Significant gains in responsivity and time jointly engaged were found post JASPER parent-mediated intervention over a psychoeducation intervention. Further, combining higher levels of responsive behaviour with greater adoption of intervention strategies was associated with greater time jointly engaged. Findings encourage a focus on enhancing responsive behaviour in parent-mediated intervention models. PMID:26797940

The relation between intrapersonal and interpersonal staff behaviour towards clients with ID and challenging behaviour: a validation study of the Staff-Client Interactive Behaviour Inventory.

PubMed

Willems, A P A M; Embregts, P J C M; Stams, G J J M; Moonen, X M H

2010-01-01

Interpersonal staff behaviour is one of the instigating factors associated with challenging behaviour in clients with intellectual disabilities (ID). There are several studies focusing on the influence of intrapersonal staff characteristics - such as beliefs, attributions and emotional reactions - on staff behaviour. Little is known, however, about interpersonal staff behaviour itself. This study describes the development and validation of the Staff-Client Interactive Behaviour Inventory (SCIBI), measuring both intrapersonal and interpersonal staff behaviour in response to challenging behaviour in clients with ID. A total of 292 staff members, employed in residential and community services, completed the SCIBI for 34 clients with ID and challenging behaviour. Confirmatory factor analysis of a seven-factor model - with assertive control, hostile, friendly and support-seeking interpersonal behaviour; proactive thinking; self-reflection; and critical expressed emotion as reliable factors - showed an exact fit to the data, indicating construct validity and reliability of the SCIBI. A series of multilevel regression analyses showed higher age of the client to be negatively associated with assertive control. Job experience, level of education, type and sex of staff predicted interpersonal behaviour. Also, intrapersonal staff behaviour, including critical expressed emotion, proactive thinking and self-reflection, predicted interpersonal behaviour. The SCIBI can be used to identify staff intrapersonal and interpersonal behaviour towards clients with ID and challenging behaviour. Results obtained with the SCIBI can provide new directions for individual client treatment plans and staff training programmes.

Effect of drugs of abuse on social behaviour: a review of animal models.

PubMed

Blanco-Gandía, Maria C; Mateos-García, Ana; García-Pardo, Maria P; Montagud-Romero, Sandra; Rodríguez-Arias, Marta; Miñarro, José; Aguilar, María A

2015-09-01

Social behaviour is disturbed in many substance abuse and psychiatric disorders. Given the consensus that social behaviours of lower mammals may help to understand some human emotional reactions, the aim of the present work was to provide an up-to-date review of studies on the changes in social behaviour induced by drugs of abuse. Various animal models have been used to study the relationship between drugs of abuse and social behaviour. Herein, we describe the effects of different substances of abuse on the three most commonly used animal models of social behaviour: the social play test, the social interaction test and the resident-intruder paradigm. The first is the most widely used test to assess adolescent behaviour in rodents, the second is generally used to evaluate a wide repertoire of behaviours in adulthood and the latter is specific to aggressive behaviour. Throughout the review we will explore the most relevant studies carried out to date to evaluate the effects of alcohol, cocaine, opioids, 3,4-methylenedioxymethamphetamine (MDMA), cannabinoids, nicotine and other drugs of abuse on these three paradigms, taking into account the influence of different variables, such as social history, age and type of exposure. Drugs of diverse pharmacological classes induce alterations in social behaviour, although they can be contrasting depending on several factors (drug, individual differences and environmental conditions). Ethanol and nicotine increase social interaction at low doses but reduce it at high doses. Psychostimulants, MDMA and cannabinoids reduce social interaction, whereas opiates increase it. Ethanol and psychostimulants enhance aggression, whereas MDMA, opiates, cannabinoids and nicotine reduce it. Prenatal drug exposure alters social behaviour, whereas drug withdrawal decreases sociability and enhances aggression. As a whole, this evidence has improved our understanding of the social dimension of drug addiction.

Human-directed social behaviour in dogs shows significant heritability.

PubMed

Persson, M E; Roth, L S V; Johnsson, M; Wright, D; Jensen, P

2015-04-01

Through domestication and co-evolution with humans, dogs have developed abilities to attract human attention, e.g. in a manner of seeking assistance when faced with a problem solving task. The aims of this study were to investigate within breed variation in human-directed contact seeking in dogs and to estimate its genetic basis. To do this, 498 research beagles, bred and kept under standardized conditions, were tested in an unsolvable problem task. Contact seeking behaviours recorded included both eye contact and physical interactions. Behavioural data was summarized through a principal component analysis, resulting in four components: test interactions, social interactions, eye contact and physical contact. Females scored significantly higher on social interactions and physical contact and age had an effect on eye contact scores. Narrow sense heritabilities (h(2) ) of the two largest components were estimated at 0.32 and 0.23 but were not significant for the last two components. These results show that within the studied dog population, behavioural variation in human-directed social behaviours was sex dependent and that the utilization of eye contact seeking increased with age and experience. Hence, heritability estimates indicate a significant genetic contribution to the variation found in human-directed social interactions, suggesting that social skills in dogs have a genetic basis, but can also be shaped and enhanced through individual experiences. This research gives the opportunity to further investigate the genetics behind dogs' social skills, which could also play a significant part into research on human social disorders such as autism. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Planned e-Learning Adoption and Occupational Socialisation in Brazilian Higher Education

ERIC Educational Resources Information Center

Renda dos Santos, Luiz Miguel; Okazaki, Shintaro

2016-01-01

This study applies the decomposed theory of planned behaviour to explore university faculty members' e-learning adoption in Brazil. Attitude (perceived usefulness, ease of use, compatibility, and relative advantage), subjective norms (external influence and student-instructor interaction), and behavioural control (level of interactivity and…

Social behaviour and illness information interact to influence the peer acceptance of children with chronic illness.

PubMed

Alderfer, M A; Wiebe, D J; Hartmann, D P

2001-09-01

Social behaviour was investigated as a contributor to the peer acceptance of children with chronic illness. We predicted that children with illness would receive less acceptance than children without illness, and that prosocial behaviour would improve acceptance, while aggressive behaviour would hamper it. Based upon attribution and cognitive bias theories, we also predicted that prosocial behaviour would be more beneficial and aggressive behaviour less damaging to the acceptance of children with illness compared to healthy children. A 3 (social behaviour: prosocial, aggressive, no information) x 2 (physical status: chronically ill, healthy) within-subjects analogue design was used. Preadolescents (N = 149) indicated social acceptance of hypothetical children portrayed in vignettes as either chronically ill or healthy with prosocial, aggressive, or no social behaviour. A 13-item social intentions scale gauged acceptance. The hypotheses were supported. Although children described as ill received lower acceptance ratings than healthy children, prosocial/ill children were more accepted than aggressive/ill children. Social behaviour interacted with physical status to affect acceptance. Social behaviour influences the peer acceptance of hypothetical children with chronic illness. Prosocial behaviour enhances acceptance of children described with illness, while aggressive behaviour hampers it. Additionally, prosocial behaviour is more beneficial, and aggressive behaviour is less damaging for children described as ill versus healthy. The potential processes by which peers judge acceptance of children with illness are discussed.

Reflective mirrors: perspective-taking in autoscopic phenomena.

PubMed

Brugger, Peter

2002-08-01

''Autoscopic phenomena refer to different illusory reduplications of one's own body and self. This article proposes a phenomenological differentiation of autoscopic reduplication into three distinct classes, i.e., autoscopic hallucinations, heautoscopy, and out-of-body experiences (OBEs). Published cases are analysed with special emphasis on the subject's point of view from which the reduplication is observed. In an autoscopic hallucination the observer's perspective is clearly body-centred, and the visual image of one's own body appears as a mirror reversal. Heautoscopy (i.e., the encounter with an alter ego or doppelgänger), is defined as a reduplication not only of bodily appearance, but also of aspects of one's psychological self. The observer's perspective may alternate between egocentric and ''alter-ego-centred''. As a consequence of the projection of bodily feelings into the doppelgänger (implying a mental rotation of one's own body along the vertical axis), original and reduplicated bodies are not mirror images of one another. This also holds for OBEs, where one's self is not reduplicated but appears to be completely dissociated from the body and observing it from a location in extracorporeal space. It is argued that perspective-taking in a spatial sense may be meaningfully related to perspective-taking in a psychological sense. The mirror in the autoscopic hallucination is a ''cognitively nonreflective mirror'' (Jean Cocteau), both spatially and psychologically. The reflective abilities of the heautoscopic mirror are better developed, yet frequent shifts in the observer's spatial perspective render the nature of psychological interactions between self and alter ego highly unpredictable. The doppelgänger may serve a transitivistic (i.e., own suffering is transferred to the alter ego) or aggressive function when this behaviour is directed against a patient. The mirror in an OBE is always reflective: It allows the self to view both space and one's psychological state from a detached but stable perspective. Spatial perspective-taking should be more thoroughly assessed in patients reporting autoscopic phenomena. By elucidating the interactions between spatial phenomenology and psychological function, we may gain important insights into the relationships between the self, its body, and phenomenal space.

The clock gene Period1 regulates innate routine behaviour in mice

PubMed Central

Bechstein, Philipp; Rehbach, Nils-Jörn; Yuhasingham, Gowzekan; Schürmann, Christoph; Göpfert, Melanie; Kössl, Manfred; Maronde, Erik

2014-01-01

Laboratory mice are well capable of performing innate routine behaviour programmes necessary for courtship, nest-building and exploratory activities although housed for decades in animal facilities. We found that in mice inactivation of the clock gene Period1 profoundly changes innate routine behaviour programmes like those necessary for courtship, nest building, exploration and learning. These results in wild-type and Period1 mutant mice, together with earlier findings on courtship behaviour in wild-type and period-mutant Drosophila melanogaster, suggest a conserved role of Period-genes on innate routine behaviour. Additionally, both per-mutant flies and Period1-mutant mice display spatial learning and memory deficits. The profound influence of Period1 on routine behaviour programmes in mice, including female partner choice, may be independent of its function as a circadian clock gene, since Period1-deficient mice display normal circadian behaviour. PMID:24598427

The clock gene Period1 regulates innate routine behaviour in mice.

PubMed

Bechstein, Philipp; Rehbach, Nils-Jörn; Yuhasingham, Gowzekan; Schürmann, Christoph; Göpfert, Melanie; Kössl, Manfred; Maronde, Erik

2014-04-22

Laboratory mice are well capable of performing innate routine behaviour programmes necessary for courtship, nest-building and exploratory activities although housed for decades in animal facilities. We found that in mice inactivation of the clock gene Period1 profoundly changes innate routine behaviour programmes like those necessary for courtship, nest building, exploration and learning. These results in wild-type and Period1 mutant mice, together with earlier findings on courtship behaviour in wild-type and period-mutant Drosophila melanogaster, suggest a conserved role of Period-genes on innate routine behaviour. Additionally, both per-mutant flies and Period1-mutant mice display spatial learning and memory deficits. The profound influence of Period1 on routine behaviour programmes in mice, including female partner choice, may be independent of its function as a circadian clock gene, since Period1-deficient mice display normal circadian behaviour.

Affective Interface Adaptations in the Musickiosk Interactive Entertainment Application

NASA Astrophysics Data System (ADS)

Malatesta, L.; Raouzaiou, A.; Pearce, L.; Karpouzis, K.

The current work presents the affective interface adaptations in the Musickiosk application. Adaptive interaction poses several open questions since there is no unique way of mapping affective factors of user behaviour to the output of the system. Musickiosk uses a non-contact interface and implicit interaction through emotional affect rather than explicit interaction where a gesture, sound or other input directly maps to an output behaviour - as in traditional entertainment applications. PAD model is used for characterizing the different affective states and emotions.

[Fathers of children born to adolescent mothers and their interactive behavior].

PubMed

Lehmann, Eva; Bergmann, Sarah; Klein, Annette M; von Klitzing, Kai

2011-01-01

Adolescent mothers and their children received much scientific attention in the past. Some studies also looked at characteristics of the interaction between mother and child. However, little is known about the interaction between children of adolescent mothers and their fathers, as research to date has focussed on paternal psychosocial aspects. The present study examines 19 partners of adolescent mothers in the interaction with their four-months-old infants. Results indicate that fathers of this sample--despite a sufficiently large intuitive repertoire--mainly relate to their infants with tactile stimulation and behaviours that facilitate eye contact. Most fathers succeed in adjusting their behaviour to their child's state. Fathers who are able to adjust their behaviour to their child's state show a larger repertoire of intuitive capacity. The infant's readiness to interact is associated with successful paternal adjustment. We discuss implications for involving fathers in the clinical work with children of adolescent mothers.

Investigating the limits of filopodial sensing: a brief report using SEM to image the interaction between 10 nm high nano-topography and fibroblast filopodia.

PubMed

Dalby, M J; Riehle, M O; Johnstone, H; Affrossman, S; Curtis, A S G

2004-01-01

Having the ability to control cell behaviour would be of great advantage in tissue engineering. One method of gaining control over cell adhesion, proliferation, guidance and differentiation is use of topography. Whilst it has be known for some time that cells can be guided by micro-topography, it is only recently becoming clear that cells will respond strongly to nano-scale topography. The fact that cells will take cues from their micro- and nano-environment suggests that the cells are in some way 'spatially aware'. It is likely that cells probe the shape of their surroundings using filopodia, and that this initial filopodia/topography interaction may be critical to down-stream cell reactions to biomaterials, or indeed, the extracellular matrix. One intriguing question is how small a feature can cells sense? In order to investigate the limits of cell sensing, high-resolution scanning electron microscopy has been used to simultaneously view cell filopodia and 10 nm high nano-islands. Fluorescence microscopy has also been used to look at adhesion formation. The results showed distinct filopodial/nano-island interaction and changes in adhesion morphology.

The study of the behaviour of a disturbed semi-infinite liquid jet using a spatial instability method

NASA Astrophysics Data System (ADS)

Basu (‧nee De), Shukla

2001-11-01

A study has been made of the behaviour of a disturbed semi-infinite liquid jet using a spatial instability method. A sinusoidal disturbance in the axial component of jet velocity at the nozzle is considered which resulted in an elliptic free surface boundary value problem with two non-linear boundary conditions. The system is linearised using perturbation techniques and the first order solution resulted in the dispersion relation. The jet stability is found to depend explicitly on the frequency of the disturbance and the Weber number. The second and third order solutions have been derived analytically which are used to predict on jet break-up and satellite formation.

Potential for using visual, auditory, and olfactory cues to manage foraging behaviour and spatial distribution of rangeland livestock

USDA-ARS?s Scientific Manuscript database

This paper reviews the literature and reports on the current state of knowledge regarding the potential for managers to use visual (VC), auditory (AC), and olfactory (OC) cues to manage foraging behavior and spatial distribution of rangeland livestock. We present evidence that free-ranging livestock...

A Choice of Terminals: Spatial Patterning in Computer Laboratories

ERIC Educational Resources Information Center

Spennemann, Dirk; Cornforth, David; Atkinson, John

2007-01-01

Purpose: This paper seeks to examine the spatial patterns of student use of machines in each laboratory to whether there are underlying commonalities. Design/methodology/approach: The research was carried out by assessing the user behaviour in 16 computer laboratories at a regional university in Australia. Findings: The study found that computers…

Long-term moderate elevation of corticosterone facilitates avian food-caching behaviour and enhances spatial memory.

PubMed

Pravosudov, Vladimir V

2003-12-22

It is widely assumed that chronic stress and corresponding chronic elevations of glucocorticoid levels have deleterious effects on animals' brain functions such as learning and memory. Some animals, however, appear to maintain moderately elevated levels of glucocorticoids over long periods of time under natural energetically demanding conditions, and it is not clear whether such chronic but moderate elevations may be adaptive. I implanted wild-caught food-caching mountain chickadees (Poecile gambeli), which rely at least in part on spatial memory to find their caches, with 90-day continuous time-release corticosterone pellets designed to approximately double the baseline corticosterone levels. Corticosterone-implanted birds cached and consumed significantly more food and showed more efficient cache recovery and superior spatial memory performance compared with placebo-implanted birds. Thus, contrary to prevailing assumptions, long-term moderate elevations of corticosterone appear to enhance spatial memory in food-caching mountain chickadees. These results suggest that moderate chronic elevation of corticosterone may serve as an adaptation to unpredictable environments by facilitating feeding and food-caching behaviour and by improving cache-retrieval efficiency in food-caching birds.

Effectiveness of small-group interactive education vs. lecture-based information-only programs on motivation to change and lifestyle behaviours. A prospective controlled trial of rehabilitation inpatients.

PubMed

Reusch, Andrea; Ströbl, Veronika; Ellgring, Heiner; Faller, Hermann

2011-02-01

Although patient education may promote motivation to change health behaviours, the most effective method has not yet been determined. This prospective, controlled trial compared an interactive, patient-oriented group program with lectures providing only information. We evaluated motivational stages of change and self-reported behaviours in three domains (sports, diet, relaxation) at four times up to one year (60% complete data) among 753 German rehabilitation inpatients (mean age 50 years, 52% male) with orthopaedic (59%) or cardiologic disorders (10%) or diabetes mellitus (31%). We found improvements between baseline and follow up regarding each outcome (p<.001) in both groups. At the end of rehabilitation, participants of the interactive group, as compared to the lectures, showed more advanced motivation regarding diet (p<.10) and sports (p=.006). Interactive group patients reported healthier diets both after 3 months (p=0.013) and 12 months (p=0.047), more relaxation behaviours (p=.029) after 3 months and higher motivation for sports after 12 months (p=.08). The superior effectiveness of the interactive group was only partly confirmed. This short, 5-session interactive program may not be superior to lectures to induce major sustainable changes in motivation. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Comparison of dogs and humans in visual scanning of social interaction.

PubMed

Törnqvist, Heini; Somppi, Sanni; Koskela, Aija; Krause, Christina M; Vainio, Outi; Kujala, Miiamaaria V

2015-09-01

Previous studies have demonstrated similarities in gazing behaviour of dogs and humans, but comparisons under similar conditions are rare, and little is known about dogs' visual attention to social scenes. Here, we recorded the eye gaze of dogs while they viewed images containing two humans or dogs either interacting socially or facing away: the results were compared with equivalent data measured from humans. Furthermore, we compared the gazing behaviour of two dog and two human populations with different social experiences: family and kennel dogs; dog experts and non-experts. Dogs' gazing behaviour was similar to humans: both species gazed longer at the actors in social interaction than in non-social images. However, humans gazed longer at the actors in dog than human social interaction images, whereas dogs gazed longer at the actors in human than dog social interaction images. Both species also made more saccades between actors in images representing non-conspecifics, which could indicate that processing social interaction of non-conspecifics may be more demanding. Dog experts and non-experts viewed the images very similarly. Kennel dogs viewed images less than family dogs, but otherwise their gazing behaviour did not differ, indicating that the basic processing of social stimuli remains similar regardless of social experiences.

An Automated, Adaptive Framework for Optimizing Preprocessing Pipelines in Task-Based Functional MRI

PubMed Central

Churchill, Nathan W.; Spring, Robyn; Afshin-Pour, Babak; Dong, Fan; Strother, Stephen C.

2015-01-01

BOLD fMRI is sensitive to blood-oxygenation changes correlated with brain function; however, it is limited by relatively weak signal and significant noise confounds. Many preprocessing algorithms have been developed to control noise and improve signal detection in fMRI. Although the chosen set of preprocessing and analysis steps (the “pipeline”) significantly affects signal detection, pipelines are rarely quantitatively validated in the neuroimaging literature, due to complex preprocessing interactions. This paper outlines and validates an adaptive resampling framework for evaluating and optimizing preprocessing choices by optimizing data-driven metrics of task prediction and spatial reproducibility. Compared to standard “fixed” preprocessing pipelines, this optimization approach significantly improves independent validation measures of within-subject test-retest, and between-subject activation overlap, and behavioural prediction accuracy. We demonstrate that preprocessing choices function as implicit model regularizers, and that improvements due to pipeline optimization generalize across a range of simple to complex experimental tasks and analysis models. Results are shown for brief scanning sessions (<3 minutes each), demonstrating that with pipeline optimization, it is possible to obtain reliable results and brain-behaviour correlations in relatively small datasets. PMID:26161667

Building the bridge between animal movement and population dynamics.

PubMed

Morales, Juan M; Moorcroft, Paul R; Matthiopoulos, Jason; Frair, Jacqueline L; Kie, John G; Powell, Roger A; Merrill, Evelyn H; Haydon, Daniel T

2010-07-27

While the mechanistic links between animal movement and population dynamics are ecologically obvious, it is much less clear when knowledge of animal movement is a prerequisite for understanding and predicting population dynamics. GPS and other technologies enable detailed tracking of animal location concurrently with acquisition of landscape data and information on individual physiology. These tools can be used to refine our understanding of the mechanistic links between behaviour and individual condition through 'spatially informed' movement models where time allocation to different behaviours affects individual survival and reproduction. For some species, socially informed models that address the movements and average fitness of differently sized groups and how they are affected by fission-fusion processes at relevant temporal scales are required. Furthermore, as most animals revisit some places and avoid others based on their previous experiences, we foresee the incorporation of long-term memory and intention in movement models. The way animals move has important consequences for the degree of mixing that we expect to find both within a population and between individuals of different species. The mixing rate dictates the level of detail required by models to capture the influence of heterogeneity and the dynamics of intra- and interspecific interaction.

Learning where to feed: the use of social information in flower-visiting Pallas' long-tongued bats (Glossophaga soricina).

PubMed

Rose, Andreas; Kolar, Miriam; Tschapka, Marco; Knörnschild, Mirjam

2016-03-01

Social learning is a widespread phenomenon among vertebrates that influences various patterns of behaviour and is often reported with respect to foraging behaviour. The use of social information by foraging bats was documented in insectivorous, carnivorous and frugivorous species, but there are little data whether flower-visiting nectarivorous bats (Phyllostomidae: Glossophaginae) can acquire information about food from other individuals. In this study, we conducted an experiment with a demonstrator-observer paradigm to investigate whether flower-visiting Pallas' long-tongued bats (Glossophaga soricina) are able to socially learn novel flower positions via observation of, or interaction with, knowledgeable conspecifics. The results demonstrate that flower-visiting G. soricina are able to use social information for the location of novel flower positions and can thereby reduce energy-costly search efforts. This social transmission is explainable as a result of local enhancement; learning bats might rely on both visual and echo-acoustical perception and are likely to eavesdrop on auditory cues that are emitted by feeding conspecifics. We additionally tested the spatial memory capacity of former demonstrator bats when retrieving a learned flower position, and the results indicate that flower-visiting bats remember a learned flower position after several weeks.

Droplets and the three-phase contact line at the nano-scale. Statics and dynamics

NASA Astrophysics Data System (ADS)

Yatsyshin, Petr; Sibley, David; Savva, Nikos; Kalliadasis, Serafim

2014-11-01

Understanding the behaviour of the solid-liquid-vapour contact line at the scale of several tens of molecular diameters is important in wetting hydrodynamics with applications in micro- and nano-fluidics, including the design of lab-on-a-chip devices and surfaces with specific wetting properties. Due to the fluid inhomogeneity at the nano-scale, the application of continuum-mechanical approaches is limited, and a natural way to remedy this is to seek descriptions accounting for the non-local molecular-level interactions. Density Functional Theory (DFT) for fluids offers a statistical-mechanical framework based on expressing the free energy of the fluid-solid pair as a functional of the spatially varying fluid density. DFT allows us to investigate small drops deposited on planar substrates whilst keeping track of the microscopic structural details of the fluid. Starting from a model of intermolecular forces, we systematically obtain interfaces, surface tensions, and the microscopic contact angle. Using a dynamic extension of equilibrium DFT, we investigate the diffusion-driven evolution of the three-phase contact line to gain insight into the dynamic behaviour of the microscopic contact angle, which is still under debate.

The influence of selective attention to auditory and visual speech on the integration of audiovisual speech information.

PubMed

Buchan, Julie N; Munhall, Kevin G

2011-01-01

Conflicting visual speech information can influence the perception of acoustic speech, causing an illusory percept of a sound not present in the actual acoustic speech (the McGurk effect). We examined whether participants can voluntarily selectively attend to either the auditory or visual modality by instructing participants to pay attention to the information in one modality and to ignore competing information from the other modality. We also examined how performance under these instructions was affected by weakening the influence of the visual information by manipulating the temporal offset between the audio and video channels (experiment 1), and the spatial frequency information present in the video (experiment 2). Gaze behaviour was also monitored to examine whether attentional instructions influenced the gathering of visual information. While task instructions did have an influence on the observed integration of auditory and visual speech information, participants were unable to completely ignore conflicting information, particularly information from the visual stream. Manipulating temporal offset had a more pronounced interaction with task instructions than manipulating the amount of visual information. Participants' gaze behaviour suggests that the attended modality influences the gathering of visual information in audiovisual speech perception.

Identifying individual male reproductive consistency in Drosophila melanogaster: The importance of controlling female behaviour.

PubMed

Balaban-Feld, Jesse; Valone, Thomas J

2017-09-01

Work on the repeatability of reproductive behaviour has mainly focused on the consistency of female preferences. We characterised the consistency of individual male Drosophila melanogaster reproductive behaviour in two experiments. In the first experiment, we allowed males to interact with a pair of live females that differed in body size. We then controlled female behaviour in a second experiment by examining the courtship behaviour of individual males interacting with a pair of decapitated females that varied in body size. In both experiments, we examined the consistency of individual male reproductive behaviour across two repeated trials on the same day. Males did not exhibit a courtship preference for the larger female in either experiment, but, in experiment 1, males did exhibit post-copulatory choice by copulating for longer durations with the large female, and males that mated with the same type of female in both trials exhibited repeatable behaviour. In general, we found weak evidence of consistent male courtship behaviour in the presence of behaving females. However, when female behaviour was controlled in experiment 2, we found that male courtship behaviour was highly repeatable. These results indicate that individual male D. melanogaster exhibit consistent reproductive behaviour and demonstrate the importance of controlling female behaviour when attempting to characterise the repeatability of male reproductive behaviour. Copyright © 2017 Elsevier B.V. All rights reserved.

The psychobiology of aggression and violence: bioethical implications.

PubMed

Díaz, José Luis

2010-01-01

Bioethics is concerned with the moral aspects of biology and medicine. The bioethical relevance of aggression and violence is clear, as very different moral and legal responsibilities may apply depending on whether aggression and violence are forms of behaviour that are innate or acquired, deliberate or automatic or not, or understandable and justifiable based on causes. Biological research and natural science theories are a basic ingredient for reflections, arguments and decisions on such matters. This study presents the problem of the causes of aggressive behaviour, the evolutionary understanding and definition of aggressive behaviour, the biological basis for this behaviour and the link between emotions and aggression. A growing body of evidence suggests that innate factors of behaviour (be they genetic or neurobiological) do not by themselves define behaviour and nor do acquired factors such as learning, cultural norms or worldviews. Both types of factor interact from the outset to shape a development process that mutually interacts to define beliefs or behaviour.

Linking models of human behaviour and climate alters projected climate change

DOE PAGES

Beckage, Brian; Gross, Louis J.; Lacasse, Katherine; ...

2018-01-01

Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioural changes that alter greenhouse gas emissions. Here, we link the C-ROADS climate model to a social model of behavioural change to examine how interactions between perceived risk and emissions behaviour influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4–6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioural uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with themore » largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioural control with perceived social norms, and behaviours leading to sustained emissions reductions. Lastly, our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.« less

Linking models of human behaviour and climate alters projected climate change

NASA Astrophysics Data System (ADS)

Beckage, Brian; Gross, Louis J.; Lacasse, Katherine; Carr, Eric; Metcalf, Sara S.; Winter, Jonathan M.; Howe, Peter D.; Fefferman, Nina; Franck, Travis; Zia, Asim; Kinzig, Ann; Hoffman, Forrest M.

2018-01-01

Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioural changes that alter greenhouse gas emissions. Here, we link the C-ROADS climate model to a social model of behavioural change to examine how interactions between perceived risk and emissions behaviour influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4-6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioural uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with the largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioural control with perceived social norms, and behaviours leading to sustained emissions reductions. Our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.

Linking models of human behaviour and climate alters projected climate change

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beckage, Brian; Gross, Louis J.; Lacasse, Katherine

Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioural changes that alter greenhouse gas emissions. Here, we link the C-ROADS climate model to a social model of behavioural change to examine how interactions between perceived risk and emissions behaviour influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4–6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioural uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with themore » largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioural control with perceived social norms, and behaviours leading to sustained emissions reductions. Lastly, our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.« less

Disruption of the Zdhhc9 intellectual disability gene leads to behavioural abnormalities in a mouse model.

PubMed

Kouskou, Marianna; Thomson, David M; Brett, Ros R; Wheeler, Lee; Tate, Rothwelle J; Pratt, Judith A; Chamberlain, Luke H

2018-06-23

Protein S-acylation is a widespread post-translational modification that regulates the trafficking and function of a diverse array of proteins. This modification is catalysed by a family of twenty-three zDHHC enzymes that exhibit both specific and overlapping substrate interactions. Mutations in the gene encoding zDHHC9 cause mild-to-moderate intellectual disability, seizures, speech and language impairment, hypoplasia of the corpus callosum and reduced volume of sub-cortical structures. In this study, we have undertaken behavioural phenotyping, magnetic resonance imaging (MRI) and isolation of S-acylated proteins to investigate the effect of disruption of the Zdhhc9 gene in mice in a C57BL/6 genetic background. Zdhhc9 mutant male mice exhibit a range of abnormalities compared with their wild-type littermates: altered behaviour in the open-field test, elevated plus maze and acoustic startle test that is consistent with a reduced anxiety level; a reduced hang time in the hanging wire test that suggests underlying hypotonia but which may also be linked to reduced anxiety; deficits in the Morris water maze test of hippocampal-dependent spatial learning and memory; and a 36% reduction in corpus callosum volume revealed by MRI. Surprisingly, membrane association and S-acylation of H-Ras was not disrupted in either whole brain or hippocampus of Zdhhc9 mutant mice, suggesting that other substrates of this enzyme are linked to the observed changes. Overall, this study highlights a key role for zDHHC9 in brain development and behaviour, and supports the utility of the Zdhhc9 mutant mouse line to investigate molecular and cellular changes linked to intellectual disability and other deficits in the human population. Copyright © 2018. Published by Elsevier Inc.

The Roles of Innate Information, Learning Rules and Plasticity in Migratory Bird Orientation

NASA Astrophysics Data System (ADS)

Able, Kenneth P.; Able, Mary A.

This paper and the following three papers were presented at the RIN97 Conference held in Oxford under the auspices of the Animal Navigation Special Interest Group, April 1997. The full proceedings, under the title Orientation and Navigation - Birds, Humans and Other Animals, can be obtained from the Director (£30 to Members, £50 to non-Members).Studies of the compass mechanisms involved in the migratory orientation of birds have revealed a complex web of interactions, both during the development of orientation behaviour in young birds and in mature individuals exhibiting migratory activity. In young birds, the acquisition of compass orientation capabilities involves the interplay of apparently genetically programmed information with a suite of innate learning rules. The latter canalise the ways in which experience with relevant orientation information from the environment impinges on development. There are many general similarities with the development of singing behaviour in songbirds, although that system is more thoroughly understood, especially at the neuronal level.Here we shall attempt to synthesise what is known about the development of compass mechanisms in a framework of innate information and learning rules. The way in which orientation behaviour develops leaves open the possibility for plasticity that enables birds to compensate for variability in the environmental cues that form the basis of their compasses. For at least some components of the system, behavioural plasticity remains into adulthood, allowing the bird on migration to respond in apparently adaptive ways to spatial and temporal variability in orientation information that it may encounter while enroute. We have studied these questions in the Savannah sparrow (Passerculus sandwichensis), a medium-distance North American emberizine nocturnal migrant. We will focus on that species, relating the results of our work to relevant studies on others.

Social behaviour of domestic dogs (Canis familiaris) in a public off-leash dog park.

PubMed

Howse, Melissa S; Anderson, Rita E; Walsh, Carolyn J

2018-03-13

This study examines the activity budgets and social behaviours initiated and received by 69 focal dogs in an off-leash dog park for 400 s after entry, a time of high activity about which little is known. Using motivationally-neutral labels for social behaviour categories, we describe the frequency of behaviours, and correlations among them. We then examine these relationships in the context of proposed functions for some behaviours in dogs, in terms of information gathering and communication, including visual and tactile signalling. Time spent with other dogs decreased rapidly over the visit, and much of this early interaction involved greeting the park newcomer. Snout-muzzle contact behaviours were ubiquitous, while other behaviours were rarely observed, including aggressive behaviours. Correlations among certain non-contact behaviours initiated and received by focal dogs are consistent with their function as visual signals that may influence the continuation and form of social interactions, and their possible role in social mimicry (i.e., play bow and pull-rear away). Age, sex, and number of dogs present in the park influenced specific aspects of dogs' activity budgets, and a few behaviours. This ethological study provides fundamental data on dog social behaviour in dog parks, about which surprisingly little has been published. Copyright © 2018 Elsevier B.V. All rights reserved.

The Interactive Minority Game: a Web-based investigation of human market interactions

NASA Astrophysics Data System (ADS)

Laureti, Paolo; Ruch, Peter; Wakeling, Joseph; Zhang, Yi-Cheng

2004-01-01

The unprecedented access offered by the World Wide Web brings with it the potential to gather huge amounts of data on human activities. Here we exploit this by using a toy model of financial markets, the Minority Game (MG), to investigate human speculative trading behaviour and information capacity. Hundreds of individuals have played a total of tens of thousands of game turns against computer-controlled agents in the Web-based Interactive Minority Game. The analytical understanding of the MG permits fine-tuning of the market situations encountered, allowing for investigation of human behaviour in a variety of controlled environments. In particular, our results indicate a transition in players’ decision-making, as the markets become more difficult, between deductive behaviour making use of short-term trends in the market, and highly repetitive behaviour that ignores entirely the market history, yet outperforms random decision-making.

Motivating forces of human actions. Neuroimaging reward and social interaction.

PubMed

Walter, Henrik; Abler, Birgit; Ciaramidaro, Angela; Erk, Susanne

2005-11-15

In neuroeconomics, reward and social interaction are central concepts to understand what motivates human behaviour. Both concepts are investigated in humans using neuroimaging methods. In this paper, we provide an overview about these results and discuss their relevance for economic behaviour. For reward it has been shown that a system exists in humans that is involved in predicting rewards and thus guides behaviour, involving a circuit including the striatum, the orbitofrontal cortex and the amygdala. Recent studies on social interaction revealed a mentalizing system representing the mental states of others. A central part of this system is the medial prefrontal cortex, in particular the anterior paracingulate cortex. The reward as well as the mentalizing system is engaged in economic decision-making. We will discuss implications of this study for neuromarketing as well as general implications of these results that may help to provide deeper insights into the motivating forces of human behaviour.

Masculinized female yellow-bellied marmots initiate more social interactions.

PubMed

Monclús, Raquel; Cook, Taylor; Blumstein, Daniel T

2012-04-23

The presence of male siblings in utero influences female morphology and life-history traits because testosterone transferred among foetuses may masculinize females. Similarly, litter sex composition might alter the display of sexually dimorphic behaviour, such as play and allogrooming, since they are modulated by androgens. We explored whether masculinization alters the frequency of play and sociopositive behaviour in female yellow-bellied marmots (Marmota flaviventris). We found that masculinized juvenile females were more likely to initiate play and allogrooming, but yearling females exhibited higher levels of oestrogen-modulated sociopositive behaviours. Additionally, the more they interacted, the greater number of different partners they interacted with. Our results suggest that masculinization increases the rate of age-dependent social behaviour. This probably works by increasing exploration that predisposes individuals to higher encounter rates. Further support comes from previous findings showing that masculinized females were more likely to disperse. Our study stresses the importance of considering litter sex composition as a fitness modulator.

Measuring Team Learning Behaviours through Observing Verbal Team Interaction

ERIC Educational Resources Information Center

Raes, Elisabeth; Boon, Anne; Kyndt, Eva; Dochy, Filip

2015-01-01

Purpose: This study aims to explore, as an answer to the observed lack of knowledge about actual team learning behaviours, the characteristics of the actual observed basic team learning behaviours and facilitating team learning behaviours more in-depth of three project teams. Over time, team learning in an organisational context has been…

The medical student as a patient: attitudes towards involvement in the quality and safety of health care.

PubMed

Davis, Rachel E; Joshi, Devavrata; Patel, Krishan; Briggs, M; Vincent, Charles A

2013-10-01

In recent years, factors that affect patients' willingness and ability to participate in safety-relevant behaviours have been investigated. However, how trained healthcare professionals or medical students would feel participating in safety-relevant behaviours as a patient in hospital remains largely unexplored. To investigate medical students' willingness to participate in behaviours related to the quality and safety of their health care. A cross-sectional exploratory study using a survey that addressed willingness to participate in different behaviours recommended by current patient safety initiatives. Three types of interactional behaviours (asking factual or challenging questions, notifying doctors or nurses of errors/problems) and three non-interactional behaviours (choosing a hospital based on the safety record, bringing medicines and a list of allergies into hospital, and reporting an error to a national reporting system) were assessed. One hundred and seventy-nine medical students from an inner city London teaching hospital participated in the study. Students' willingness to participate was affected (P < 0.05) by the action required by the patient and (for interactional behaviours) whether the patient was engaging in the specific action with a doctor or nurse. Students were least willing to ask 'challenging' questions to doctors and nurses and to report errors to a national reporting system. Doctors' and nurses' encouragement appeared to increase self-reported willingness to participate in behaviours where baseline willingness was low. Similar to research on lay patient populations; medical students do not view involvement in safety-related behaviours equally. Interventions should be tailored at encouraging students to participate in behaviours they are less inclined to take on an active role in. Future research is required to examine students' motivations for participation in this important but heavily under-researched area. © 2012 John Wiley & Sons Ltd.

Risk behaviours among early adolescents: risk and protective factors.

PubMed

Wang, Ruey-Hsia; Hsu, Hsiu-Yueh; Lin, Shu-Yuan; Cheng, Chung-Ping; Lee, Shu-Li

2010-02-01

This paper is a report of a study conducted to examine the influence of risk/protective factors on risk behaviours of early adolescents and whether protective factors moderate their impact. An understanding of how risk and protective factors operate to influence risk behaviours of early adolescents will better prepare nurses to perform interventions appropriately to reduce risk behaviours of early adolescents. A cross-sectional study was carried out, based on a sample of public junior high schools (from 7th to 9th grades) in one city and one county in Taiwan. An anonymous questionnaire designed to measure five risk factors, six protective factors and risk behaviours was administered from October 2006 to March 2007. Data from 878 students were used for the present analysis. Pearson's correlations, anova with random effect models, and generalized linear models were used to analyse the statistically significant explanatory variables for risk behaviours. Gender, perceived father's risk behaviour, perceived mother's risk behaviour, health self-efficacy, interaction of health self-efficacy and perceived peers' risk behaviour, and interaction of emotional regulation and perceived peers' risk behaviour were statistically significant explanatory variables of risk behaviours. Health self-efficacy and emotional regulation moderated the negative effects of peers' perceived risk behaviour on risk behaviours. All protective factors were negative statistically correlated with risk behaviours, and all risk factors positively statistically correlated with risk behaviours. Male adolescents should be considered an at-risk group for risk behaviour intervention. Nurses could provide early adolescents with training regarding health self-efficacy improvement, self-esteem enhancement, emotional regulation skills to reduce their risk behaviours.

Patterns of contribution to citizen science biodiversity projects increase understanding of volunteers' recording behaviour.

PubMed

Boakes, Elizabeth H; Gliozzo, Gianfranco; Seymour, Valentine; Harvey, Martin; Smith, Chloë; Roy, David B; Haklay, Muki

2016-09-13

The often opportunistic nature of biological recording via citizen science leads to taxonomic, spatial and temporal biases which add uncertainty to biodiversity estimates. However, such biases may also give valuable insight into volunteers' recording behaviour. Using Greater London as a case-study we examined the composition of three citizen science datasets - from Greenspace Information for Greater London CIC, iSpot and iRecord - with respect to recorder contribution and spatial and taxonomic biases, i.e. when, where and what volunteers record. We found most volunteers contributed few records and were active for just one day. Each dataset had its own taxonomic and spatial signature suggesting that volunteers' personal recording preferences may attract them towards particular schemes. There were also patterns across datasets: species' abundance and ease of identification were positively associated with number of records, as was plant height. We found clear hotspots of recording activity, the 10 most popular sites containing open water. We note that biases are accrued as part of the recording process (e.g. species' detectability) as well as from volunteer preferences. An increased understanding of volunteer behaviour gained from analysing the composition of records could thus enhance the fit between volunteers' interests and the needs of scientific projects.

Population-Scale Foraging Segregation in an Apex Predator of the North Atlantic

PubMed Central

Paiva, Vitor H.; Fagundes, Ana I.; Romão, Vera; Gouveia, Cátia; Ramos, Jaime A.

2016-01-01

In this work we investigated the between-colony spatial, behavioural and trophic segregation of two sub-populations of the elusive Macaronesian shearwaters Puffinus baroli breeding only ~340 km apart in Cima Islet (Porto Santo Island) and Selvagem Grande Island. Global location sensing (gls) loggers were used in combination with the trophic ecology of tracked individuals, inferred from the isotopic signatures of wing feathers. Results suggest that these two Macaronesian shearwater sub-populations do segregate during the non-breeding period in some ‘sub-population-specific’ regions, by responding to different oceanographic characteristics (habitat modelling). Within these disparate areas, both sub-populations behave differently (at-sea activity) and prey on disparate trophic niches (stable isotope analysis). One hypothesis would be that each sub-population have evolved and adapted to feed on particular and ‘sub-population-specific’ resources, and the segregation observed at the three different levels (spatial, behavioural and trophic) might be in fact a result of such adaptation, from the emergence of ‘cultural foraging patterns’. Finally, when comparing to the results of former studies reporting on the spatial, behavioural and trophic choices of Macaronesian shearwater populations breeding on Azores and Canary Islands, we realized the high ecological plasticity of this species inhabiting and foraging over the North-East Atlantic Ocean. PMID:27003687

Patterns of contribution to citizen science biodiversity projects increase understanding of volunteers’ recording behaviour

PubMed Central

Boakes, Elizabeth H.; Gliozzo, Gianfranco; Seymour, Valentine; Harvey, Martin; Smith, Chloë; Roy, David B.; Haklay, Muki

2016-01-01

The often opportunistic nature of biological recording via citizen science leads to taxonomic, spatial and temporal biases which add uncertainty to biodiversity estimates. However, such biases may also give valuable insight into volunteers’ recording behaviour. Using Greater London as a case-study we examined the composition of three citizen science datasets – from Greenspace Information for Greater London CIC, iSpot and iRecord - with respect to recorder contribution and spatial and taxonomic biases, i.e. when, where and what volunteers record. We found most volunteers contributed few records and were active for just one day. Each dataset had its own taxonomic and spatial signature suggesting that volunteers’ personal recording preferences may attract them towards particular schemes. There were also patterns across datasets: species’ abundance and ease of identification were positively associated with number of records, as was plant height. We found clear hotspots of recording activity, the 10 most popular sites containing open water. We note that biases are accrued as part of the recording process (e.g. species’ detectability) as well as from volunteer preferences. An increased understanding of volunteer behaviour gained from analysing the composition of records could thus enhance the fit between volunteers’ interests and the needs of scientific projects. PMID:27619155

Conservation physiology of animal migration

PubMed Central

Lennox, Robert J.; Chapman, Jacqueline M.; Souliere, Christopher M.; Tudorache, Christian; Wikelski, Martin; Metcalfe, Julian D.; Cooke, Steven J.

2016-01-01

Migration is a widespread phenomenon among many taxa. This complex behaviour enables animals to exploit many temporally productive and spatially discrete habitats to accrue various fitness benefits (e.g. growth, reproduction, predator avoidance). Human activities and global environmental change represent potential threats to migrating animals (from individuals to species), and research is underway to understand mechanisms that control migration and how migration responds to modern challenges. Focusing on behavioural and physiological aspects of migration can help to provide better understanding, management and conservation of migratory populations. Here, we highlight different physiological, behavioural and biomechanical aspects of animal migration that will help us to understand how migratory animals interact with current and future anthropogenic threats. We are in the early stages of a changing planet, and our understanding of how physiology is linked to the persistence of migratory animals is still developing; therefore, we regard the following questions as being central to the conservation physiology of animal migrations. Will climate change influence the energetic costs of migration? Will shifting temperatures change the annual clocks of migrating animals? Will anthropogenic influences have an effect on orientation during migration? Will increased anthropogenic alteration of migration stopover sites/migration corridors affect the stress physiology of migrating animals? Can physiological knowledge be used to identify strategies for facilitating the movement of animals? Our synthesis reveals that given the inherent challenges of migration, additional stressors derived from altered environments (e.g. climate change, physical habitat alteration, light pollution) or interaction with human infrastructure (e.g. wind or hydrokinetic turbines, dams) or activities (e.g. fisheries) could lead to long-term changes to migratory phenotypes. However, uncertainty remains because of the complexity of biological systems, the inherently dynamic nature of the environment and the scale at which many migrations occur and associated threats operate, necessitating improved integration of physiological approaches to the conservation of migratory animals. PMID:27293751

Addressing population heterogeneity and distribution in epidemics models using a cellular automata approach

PubMed Central

2014-01-01

Background The spread of an infectious disease is determined by biological and social factors. Models based on cellular automata are adequate to describe such natural systems consisting of a massive collection of simple interacting objects. They characterize the time evolution of the global system as the emergent behaviour resulting from the interaction of the objects, whose behaviour is defined through a set of simple rules that encode the individual behaviour and the transmission dynamic. Methods An epidemic is characterized trough an individual–based–model built upon cellular automata. In the proposed model, each individual of the population is represented by a cell of the automata. This way of modeling an epidemic situation allows to individually define the characteristic of each individual, establish different scenarios and implement control strategies. Results A cellular automata model to study the time evolution of a heterogeneous populations through the various stages of disease was proposed, allowing the inclusion of individual heterogeneity, geographical characteristics and social factors that determine the dynamic of the desease. Different assumptions made to built the classical model were evaluated, leading to following results: i) for low contact rate (like in quarantine process or low density population areas) the number of infective individuals is lower than other areas where the contact rate is higher, and ii) for different initial spacial distributions of infected individuals different epidemic dynamics are obtained due to its influence on the transition rate and the reproductive ratio of disease. Conclusions The contact rate and spatial distributions have a central role in the spread of a disease. For low density populations the spread is very low and the number of infected individuals is lower than in highly populated areas. The spacial distribution of the population and the disease focus as well as the geographical characteristic of the area play a central role in the dynamics of the desease. PMID:24725804

Addressing population heterogeneity and distribution in epidemics models using a cellular automata approach.

PubMed

López, Leonardo; Burguerner, Germán; Giovanini, Leonardo

2014-04-12

The spread of an infectious disease is determined by biological and social factors. Models based on cellular automata are adequate to describe such natural systems consisting of a massive collection of simple interacting objects. They characterize the time evolution of the global system as the emergent behaviour resulting from the interaction of the objects, whose behaviour is defined through a set of simple rules that encode the individual behaviour and the transmission dynamic. An epidemic is characterized trough an individual-based-model built upon cellular automata. In the proposed model, each individual of the population is represented by a cell of the automata. This way of modeling an epidemic situation allows to individually define the characteristic of each individual, establish different scenarios and implement control strategies. A cellular automata model to study the time evolution of a heterogeneous populations through the various stages of disease was proposed, allowing the inclusion of individual heterogeneity, geographical characteristics and social factors that determine the dynamic of the desease. Different assumptions made to built the classical model were evaluated, leading to following results: i) for low contact rate (like in quarantine process or low density population areas) the number of infective individuals is lower than other areas where the contact rate is higher, and ii) for different initial spacial distributions of infected individuals different epidemic dynamics are obtained due to its influence on the transition rate and the reproductive ratio of disease. The contact rate and spatial distributions have a central role in the spread of a disease. For low density populations the spread is very low and the number of infected individuals is lower than in highly populated areas. The spacial distribution of the population and the disease focus as well as the geographical characteristic of the area play a central role in the dynamics of the desease.

Conservation physiology of animal migration.

PubMed

Lennox, Robert J; Chapman, Jacqueline M; Souliere, Christopher M; Tudorache, Christian; Wikelski, Martin; Metcalfe, Julian D; Cooke, Steven J

2016-01-01

Migration is a widespread phenomenon among many taxa. This complex behaviour enables animals to exploit many temporally productive and spatially discrete habitats to accrue various fitness benefits (e.g. growth, reproduction, predator avoidance). Human activities and global environmental change represent potential threats to migrating animals (from individuals to species), and research is underway to understand mechanisms that control migration and how migration responds to modern challenges. Focusing on behavioural and physiological aspects of migration can help to provide better understanding, management and conservation of migratory populations. Here, we highlight different physiological, behavioural and biomechanical aspects of animal migration that will help us to understand how migratory animals interact with current and future anthropogenic threats. We are in the early stages of a changing planet, and our understanding of how physiology is linked to the persistence of migratory animals is still developing; therefore, we regard the following questions as being central to the conservation physiology of animal migrations. Will climate change influence the energetic costs of migration? Will shifting temperatures change the annual clocks of migrating animals? Will anthropogenic influences have an effect on orientation during migration? Will increased anthropogenic alteration of migration stopover sites/migration corridors affect the stress physiology of migrating animals? Can physiological knowledge be used to identify strategies for facilitating the movement of animals? Our synthesis reveals that given the inherent challenges of migration, additional stressors derived from altered environments (e.g. climate change, physical habitat alteration, light pollution) or interaction with human infrastructure (e.g. wind or hydrokinetic turbines, dams) or activities (e.g. fisheries) could lead to long-term changes to migratory phenotypes. However, uncertainty remains because of the complexity of biological systems, the inherently dynamic nature of the environment and the scale at which many migrations occur and associated threats operate, necessitating improved integration of physiological approaches to the conservation of migratory animals.

Trapping and desorption of complex organic molecules in water at 20 K

NASA Astrophysics Data System (ADS)

Burke, Daren J.; Puletti, Fabrizio; Woods, Paul M.; Viti, Serena; Slater, Ben; Brown, Wendy A.

2015-10-01

The formation, chemical, and thermal processing of complex organic molecules (COMs) is currently a topic of much interest in interstellar chemistry. The isomers glycolaldehyde, methyl formate, and acetic acid are particularly important because of their role as pre-biotic species. It is becoming increasingly clear that many COMs are formed within interstellar ices which are dominated by water. Hence, the interaction of these species with water ice is crucially important in dictating their behaviour. Here, we present the first detailed comparative study of the adsorption and thermal processing of glycolaldehyde, methyl formate, and acetic acid adsorbed on and in water ices at astrophysically relevant temperatures (20 K). We show that the functional group of the isomer dictates the strength of interaction with water ice, and hence the resulting desorption and trapping behaviour. Furthermore, the strength of this interaction directly affects the crystallization of water, which in turn affects the desorption behaviour. Our detailed coverage and composition dependent data allow us to categorize the desorption behaviour of the three isomers on the basis of the strength of intermolecular and intramolecular interactions, as well as the natural sublimation temperature of the molecule. This categorization is extended to other C, H, and O containing molecules in order to predict and describe the desorption behaviour of COMs from interstellar ices.

The interplay of gender and social background: A longitudinal study of interaction effects in reading attitudes and behaviour.

PubMed

Becker, Michael; McElvany, Nele

2017-11-15

Researchers often report and discuss gender differences. However, recent research has drawn attention to interaction effects between gender and other social categories. This study analysed the development of disparities in students' reading-related self-concept, intrinsic motivation, and behaviour, as they relate to differences in gender and socio-economic family background. Drawing on expectancy-value theory, we regarded reading-related self-concept, motivation, and behaviour as key to explaining the growing differences between boys and girls in adolescence. Specifically, we focused on the interaction between gender and socio-economic background in children, which has been discussed in the context of moderating gender differences but not in the context of reading-related attitudes and behaviour. The investigation is based on a longitudinal sample of N = 717 German students between third and sixth grades. We used questionnaire data from both students and parents. To compare students' development across time, we applied multigroup latent growth curve models. We found evidence of increasing gender differences, which were also moderated by the socio-economic status (SES) of parents: a gender gap either already existed (intrinsic motivation and reading behaviour) or intensified (reading self-concept and reading behaviour) between third and sixth grades. The interaction of gender and SES seemed particularly important for reading self-concept, with the gender gap growing less substantially for higher-SES children. Moreover, this pattern persisted for reading self-concept, even when controlling for achievement differences. The results provide evidence that gender, social background, and the interaction of the two are relevant for development in the domain of reading, even in young children. © 2017 The British Psychological Society.

Skeletal trauma reflects hunting behaviour in extinct sabre-tooth cats and dire wolves.

PubMed

Brown, Caitlin; Balisi, Mairin; Shaw, Christopher A; Van Valkenburgh, Blaire

2017-04-10

Skeletal-injury frequency and distribution are likely to reflect hunting behaviour in predatory vertebrates and might therefore differ between species with distinct hunting modes. Two Pleistocene predators from the Rancho La Brea asphalt seeps, the sabre-tooth cat, Smilodon fatalis, and dire wolf, Canis dirus, represent ambush and pursuit predators, respectively. On the basis of a collection of over 1,900 pathological elements, the frequency of traumatic injury across skeletal elements in these two species was calculated. Here we show that the frequency of trauma in the sabre-tooth cat exceeds that of the dire wolf (4.3% compared to 2.8%), implying that the killing behaviour of S. fatalis entailed greater risk of injury. The distribution of traumatic injuries also differed between the two species. S. fatalis, an ambush predator, was injured more often than expected across the lumbar vertebrae and shoulders whereas C. dirus, a pursuit predator, had higher than expected levels of injury in the limbs and cervical vertebrae. Spatial analysis was used to quantify differences in the distribution of putative hunting injuries. Analysis of injury locations discriminated true hotspots from injury-dense areas and facilitated interpretation of predatory behaviour, demonstrating the use of spatial analyses in the study of vertebrate behaviour and evolution. These results suggest that differences in trauma distribution reflect distinct hazards of each species' hunting mode.

Kinematic behaviour of a large earthflow defined by surface displacement monitoring, DEM differencing, and ERT imaging

NASA Astrophysics Data System (ADS)

Prokešová, Roberta; Kardoš, Miroslav; Tábořík, Petr; Medveďová, Alžbeta; Stacke, Václav; Chudý, František

2014-11-01

Large earthflow-type landslides are destructive mass movement phenomena with highly unpredictable behaviour. Knowledge of earthflow kinematics is essential for understanding the mechanisms that control its movements. The present paper characterises the kinematic behaviour of a large earthflow near the village of Ľubietová in Central Slovakia over a period of 35 years following its most recent reactivation in 1977. For this purpose, multi-temporal spatial data acquired by point-based in-situ monitoring and optical remote sensing methods have been used. Quantitative data analyses including strain modelling and DEM differencing techniques have enabled us to: (i) calculate the annual landslide movement rates; (ii) detect the trend of surface displacements; (iii) characterise spatial variability of movement rates; (iv) measure changes in the surface topography on a decadal scale; and (v) define areas with distinct kinematic behaviour. The results also integrate the qualitative characteristics of surface topography, in particular the distribution of surface structures as defined by a high-resolution DEM, and the landslide subsurface structure, as revealed by 2D resistivity imaging. Then, the ground surface kinematics of the landslide is evaluated with respect to the specific conditions encountered in the study area including slope morphology, landslide subsurface structure, and local geological and hydrometeorological conditions. Finally, the broader implications of the presented research are discussed with particular focus on the role that strain-related structures play in landslide kinematic behaviour.

The role of genes in talking about overweight: An analysis of discourse on genetics, overweight and health risks in relation to nutrigenomics.

PubMed

Komduur, Rixt; Te Molder, Hedwig

2014-11-01

This study examines whether the assumptions embedded in nutrigenomics, especially the alleged relation between information about personal health risks and healthy behaviour, match how people account for the relation between food, health and genes in everyday life. We draw on discourse analysis to study accounts of overweight in six group interviews with people who are and who are not overweight. The results show potentially contradictory normative orientations towards behavioural explanations of (over)weight. Overt gene accounts are interactionally problematic (in contrast to more indirect accounts such as 'build'), indicating that participants treat 'behaviour' as the normatively appropriate explanation for overweight. At the same time, however, healthy behaviour is an accountable matter, i.e. it is dealt with in interaction as behaviour that is not self-evidently right but requires an explanation. It is discussed how bringing these interactional concerns to the surface is essential for understanding future users' response to nutrigenomics and emergent technologies more in general. © The Author(s) 2013.

Oxytocin, brain physiology, and functional connectivity: a review of intranasal oxytocin fMRI studies.

PubMed

Bethlehem, Richard A I; van Honk, Jack; Auyeung, Bonnie; Baron-Cohen, Simon

2013-07-01

In recent years the neuropeptide oxytocin (OT) has become one of the most studied peptides of the human neuroendocrine system. Research has shown widespread behavioural effects and numerous potential therapeutic benefits. However, little is known about how OT triggers these effects in the brain. Here, we discuss some of the physiological properties of OT in the human brain including the long half-life of neuropeptides, the diffuse projections of OT throughout the brain and interactions with other systems such as the dopaminergic system. These properties indicate that OT acts without clear spatial and temporal specificity. Therefore, it is likely to have widespread effects on the brain's intrinsic functioning. Additionally, we review studies that have used functional magnetic resonance imaging (fMRI) concurrently with OT administration. These studies reveal a specific set of 'social' brain regions that are likely to be the strongest targets for OT's potential to influence human behaviour. On the basis of the fMRI literature and the physiological properties of the neuropeptide, we argue that OT has the potential to not only modulate activity in a set of specific brain regions, but also the functional connectivity between these regions. In light of the increasing knowledge of the behavioural effects of OT in humans, studies of the effects of OT administration on brain function can contribute to our understanding of the neural networks in the social brain. Copyright © 2012 Elsevier Ltd. All rights reserved.

Automatic Visual Tracking and Social Behaviour Analysis with Multiple Mice

PubMed Central

Giancardo, Luca; Sona, Diego; Huang, Huiping; Sannino, Sara; Managò, Francesca; Scheggia, Diego; Papaleo, Francesco; Murino, Vittorio

2013-01-01

Social interactions are made of complex behavioural actions that might be found in all mammalians, including humans and rodents. Recently, mouse models are increasingly being used in preclinical research to understand the biological basis of social-related pathologies or abnormalities. However, reliable and flexible automatic systems able to precisely quantify social behavioural interactions of multiple mice are still missing. Here, we present a system built on two components. A module able to accurately track the position of multiple interacting mice from videos, regardless of their fur colour or light settings, and a module that automatically characterise social and non-social behaviours. The behavioural analysis is obtained by deriving a new set of specialised spatio-temporal features from the tracker output. These features are further employed by a learning-by-example classifier, which predicts for each frame and for each mouse in the cage one of the behaviours learnt from the examples given by the experimenters. The system is validated on an extensive set of experimental trials involving multiple mice in an open arena. In a first evaluation we compare the classifier output with the independent evaluation of two human graders, obtaining comparable results. Then, we show the applicability of our technique to multiple mice settings, using up to four interacting mice. The system is also compared with a solution recently proposed in the literature that, similarly to us, addresses the problem with a learning-by-examples approach. Finally, we further validated our automatic system to differentiate between C57B/6J (a commonly used reference inbred strain) and BTBR T+tf/J (a mouse model for autism spectrum disorders). Overall, these data demonstrate the validity and effectiveness of this new machine learning system in the detection of social and non-social behaviours in multiple (>2) interacting mice, and its versatility to deal with different experimental settings and scenarios. PMID:24066146

Developmental Perspectives on Prosocial and Aggressive Motives in Preschoolers' Peer Interactions

ERIC Educational Resources Information Center

Persson, Gun E. B.

2005-01-01

Preschoolers' prosocial and aggressive behaviours were explored longitudinally, with a focus on the inferred underlying motives of these behaviours. Forty-four children (initially 22-40 months of age) were observed in naturalistic interactions with peers, during a 2-month period, for each of three consecutive years. Three categories of prosocial…

Peer Interactions among Children with Profound Intellectual and Multiple Disabilities during Group Activities

ERIC Educational Resources Information Center

Nijs, Sara; Penne, Anneleen; Vlaskamp, Carla; Maes, Bea

2016-01-01

Background: Children with profound intellectual and multiple disabilities (PIMD) meet other children with PIMD in day care centres or schools. This study explores the peer-directed behaviours of children with PIMD, the peer interaction-influencing behaviour of the direct support workers and the children's positioning. Method: Group activities for…

The Intersubjective and Transitional Function of Imitation in Early Grandparent-Infant Grandchild Interaction

ERIC Educational Resources Information Center

Kokkinaki, Theano; Pratikaki, Anastasia

2014-01-01

Primary objective: Research has provided evidence of the intersubjective function of imitation in grandparent-infant interaction based on the basic aspects of imitation. This lacks the systematic investigation of behaviour dynamics framing spontaneous imitation. The aim of this study was to compare the dyadic expressive behaviours (vocal, kinetic…

Monte Carlo Planning Method Estimates Planning Horizons during Interactive Social Exchange.

PubMed

Hula, Andreas; Montague, P Read; Dayan, Peter

2015-06-01

Reciprocating interactions represent a central feature of all human exchanges. They have been the target of various recent experiments, with healthy participants and psychiatric populations engaging as dyads in multi-round exchanges such as a repeated trust task. Behaviour in such exchanges involves complexities related to each agent's preference for equity with their partner, beliefs about the partner's appetite for equity, beliefs about the partner's model of their partner, and so on. Agents may also plan different numbers of steps into the future. Providing a computationally precise account of the behaviour is an essential step towards understanding what underlies choices. A natural framework for this is that of an interactive partially observable Markov decision process (IPOMDP). However, the various complexities make IPOMDPs inordinately computationally challenging. Here, we show how to approximate the solution for the multi-round trust task using a variant of the Monte-Carlo tree search algorithm. We demonstrate that the algorithm is efficient and effective, and therefore can be used to invert observations of behavioural choices. We use generated behaviour to elucidate the richness and sophistication of interactive inference.

Social interaction-induced activation of RNA splicing in the amygdala of microbiome-deficient mice.

PubMed

Stilling, Roman M; Moloney, Gerard M; Ryan, Feargal J; Hoban, Alan E; Bastiaanssen, Thomaz Fs; Shanahan, Fergus; Clarke, Gerard; Claesson, Marcus J; Dinan, Timothy G; Cryan, John F

2018-05-29

Social behaviour is regulated by activity of host-associated microbiota across multiple species. However, the molecular mechanisms mediating this relationship remain elusive. We therefore determined the dynamic, stimulus-dependent transcriptional regulation of germ-free (GF) and GF mice colonised post weaning (exGF) in the amygdala, a brain region critically involved in regulating social interaction. In GF mice the dynamic response seen in controls was attenuated and replaced by a marked increase in expression of splicing factors and alternative exon usage in GF mice upon stimulation, which was even more pronounced in exGF mice. In conclusion, we demonstrate a molecular basis for how the host microbiome is crucial for a normal behavioural response during social interaction. Our data further suggest that social behaviour is correlated with the gene-expression response in the amygdala, established during neurodevelopment as a result of host-microbe interactions. Our findings may help toward understanding neurodevelopmental events leading to social behaviour dysregulation, such as those found in autism spectrum disorders (ASDs). © 2018, Stilling et al.

Monte Carlo Planning Method Estimates Planning Horizons during Interactive Social Exchange

PubMed Central

Hula, Andreas; Montague, P. Read; Dayan, Peter

2015-01-01

Reciprocating interactions represent a central feature of all human exchanges. They have been the target of various recent experiments, with healthy participants and psychiatric populations engaging as dyads in multi-round exchanges such as a repeated trust task. Behaviour in such exchanges involves complexities related to each agent’s preference for equity with their partner, beliefs about the partner’s appetite for equity, beliefs about the partner’s model of their partner, and so on. Agents may also plan different numbers of steps into the future. Providing a computationally precise account of the behaviour is an essential step towards understanding what underlies choices. A natural framework for this is that of an interactive partially observable Markov decision process (IPOMDP). However, the various complexities make IPOMDPs inordinately computationally challenging. Here, we show how to approximate the solution for the multi-round trust task using a variant of the Monte-Carlo tree search algorithm. We demonstrate that the algorithm is efficient and effective, and therefore can be used to invert observations of behavioural choices. We use generated behaviour to elucidate the richness and sophistication of interactive inference. PMID:26053429

Is it safe to nest near conspicuous neighbours? Spatial patterns in predation risk associated with the density of American Golden-Plover nests.

PubMed

Giroux, Marie-Andrée; Trottier-Paquet, Myriam; Bêty, Joël; Lamarre, Vincent; Lecomte, Nicolas

2016-01-01

Predation is one of the main factors explaining nesting mortality in most bird species. Birds can avoid nest predation or reduce predation pressure by breeding at higher latitude, showing anti-predator behaviour, selecting nest sites protected from predators, and nesting in association with protective species. American Golden-Plovers (Pluvialis dominica) defend their territory by using various warning and distraction behaviours displayed at varying levels of intensity (hereafter "conspicuous behaviour"), as well as more aggressive behaviours such as aerial attacks, but only in some populations. Such antipredator behaviour has the potential to repel predators and thus benefit the neighbouring nests by decreasing their predation risk. Yet, conspicuous behaviour could also attract predators by signalling the presence of a nest. To test for the existence of a protective effect associated with the conspicuous antipredator behaviour of American Golden-Plovers, we studied the influence of proximity to plover nests on predation risk of artificial nests on Igloolik Island (Nunavut, Canada) in July 2014. We predicted that the predation risk of artificial nests would decrease with proximity to and density of plover nests. We monitored 18 plover nests and set 35 artificial nests at 30, 50, 100, 200, and 500 m from seven of those plover nests. We found that the predation risk of artificial nests increases with the density of active plover nests. We also found a significant negative effect of the distance to the nearest active protector nest on predation risk of artificial nests. Understanding how the composition and structure of shorebird communities generate spatial patterns in predation risks represents a key step to better understand the importance of these species of conservation concern in tundra food webs.

Local overfishing may be avoided by examining parameters of a spatio-temporal model

PubMed Central

Shackell, Nancy; Mills Flemming, Joanna

2017-01-01

Spatial erosion of stock structure through local overfishing can lead to stock collapse because fish often prefer certain locations, and fisheries tend to focus on those locations. Fishery managers are challenged to maintain the integrity of the entire stock and require scientific approaches that provide them with sound advice. Here we propose a Bayesian hierarchical spatio-temporal modelling framework for fish abundance data to estimate key parameters that define spatial stock structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). The consideration of these spatial parameters in the stock assessment process can help identify the erosion of structure and assist in preventing local overfishing. We use Atlantic cod (Gadus morhua) in eastern Canada as a case study an examine the behaviour of these parameters from the height of the fishery through its collapse. We identify clear signals in parameter behaviour under circumstances of destructive stock erosion as well as for recovery of spatial structure even when combined with a non-recovery in abundance. Further, our model reveals the spatial pattern of areas of high and low density persists over the 41 years of available data and identifies the remnant patches. Models of this sort are crucial to recovery plans if we are to identify and protect remaining sources of recolonization for Atlantic cod. Our method is immediately applicable to other exploited species. PMID:28886179

Local overfishing may be avoided by examining parameters of a spatio-temporal model.

PubMed

Carson, Stuart; Shackell, Nancy; Mills Flemming, Joanna

2017-01-01

Spatial erosion of stock structure through local overfishing can lead to stock collapse because fish often prefer certain locations, and fisheries tend to focus on those locations. Fishery managers are challenged to maintain the integrity of the entire stock and require scientific approaches that provide them with sound advice. Here we propose a Bayesian hierarchical spatio-temporal modelling framework for fish abundance data to estimate key parameters that define spatial stock structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). The consideration of these spatial parameters in the stock assessment process can help identify the erosion of structure and assist in preventing local overfishing. We use Atlantic cod (Gadus morhua) in eastern Canada as a case study an examine the behaviour of these parameters from the height of the fishery through its collapse. We identify clear signals in parameter behaviour under circumstances of destructive stock erosion as well as for recovery of spatial structure even when combined with a non-recovery in abundance. Further, our model reveals the spatial pattern of areas of high and low density persists over the 41 years of available data and identifies the remnant patches. Models of this sort are crucial to recovery plans if we are to identify and protect remaining sources of recolonization for Atlantic cod. Our method is immediately applicable to other exploited species.

Moderating role of the MAOA genotype in antisocial behaviour.

PubMed

Fergusson, David M; Boden, Joseph M; Horwood, L John; Miller, Allison; Kennedy, Martin A

2012-02-01

Recent studies have examined gene×environment (G×E) interactions involving the monoamine oxidase A (MAOA) gene in moderating the associations between exposure to adversity and antisocial behaviour. The present study examined a novel method for assessing interactions between a single gene and multiple risk factors related to environmental and personal adversity. To test the hypothesis that the presence of the low-activity MAOA genotype was associated with an increased response to a series of risk factors. Participants were 399 males from the Christchurch Health and Development Study who had complete data on: (a) MAOA promoter region variable number tandem repeat genotype; (b) antisocial behaviour (criminal offending) to age 30 and convictions to age 21; and (c) maternal smoking during pregnancy, IQ, childhood maltreatment and school failure. Poisson regression models were fitted to three antisocial behaviour outcomes (property/violent offending ages 15-30; and convictions ages 17-21), using measures of exposure to adverse childhood circumstances. The analyses revealed consistent evidence of G x E interactions, such that those with the low-activity MAOA variant who were exposed to adversity in childhood were significantly more likely to report offending in late adolescence and early adulthood. The present findings add to the evidence suggesting that there is a stable G x E interaction involving MAOA, a range of adverse environmental and personal factors, and antisocial behaviour across the life course. These analyses also demonstrate the utility of using multiple environmental/personal exposures to test G×E interactions.

Behavioural conditioning of immune functions: how the central nervous system controls peripheral immune responses by evoking associative learning processes.

PubMed

Riether, Carsten; Doenlen, Raphaël; Pacheco-López, Gustavo; Niemi, Maj-Britt; Engler, Andrea; Engler, Harald; Schedlowski, Manfred

2008-01-01

During the last 30 years of psychoneuroimmunology research the intense bi-directional communication between the central nervous system (CNS) and the immune system has been demonstrated in studies on the interaction between the nervous-endocrine-immune systems. One of the most intriguing examples of such interaction is the capability of the CNS to associate an immune status with specific environmental stimuli. In this review, we systematically summarize experimental evidence demonstrating the behavioural conditioning of peripheral immune functions. In particular, we focus on the mechanisms underlying the behavioural conditioning process and provide a theoretical framework that indicates the potential feasibility of behaviourally conditioned immune changes in clinical situations.

Contaminant mixtures interact to impair predator-avoidance behaviours and survival in a larval amphibian.

PubMed

Sievers, Michael; Hale, Robin; Swearer, Stephen E; Parris, Kirsten M

2018-06-14

Global declines in amphibian populations are a significant conservation concern, and environmental contamination is likely a contributing driver. Although direct toxicity may be partly responsible, contaminants are often present at sub-lethal concentrations in the wild. Behavioural end-points are becoming an increasingly useful method to estimate the impact of contaminants, particularly if the behavioural responses manifest to affect individual fitness (i.e. survival, growth, or reproduction). In the wild, most animals are affected by multiple stressors, and determining how these interact to affect behaviour is critical for understanding the ecological implications of contaminant exposure. Here, we examined the individual and interactive effect of the heavy metal copper and the insecticide imidacloprid on mortality rates and anti-predator behaviours of spotted marsh frog (Limnodynastes tasmaniensis) tadpoles. This common species frequently occupies and breeds in contaminated stormwater and agricultural wetlands, where copper and imidacloprid are often present. These contaminants may alter behaviour via physiological and neurological pathways, as well as affecting how tadpoles respond to chemical cues. Tadpoles suffered unexpectedly high mortality rates when exposed to imidacloprid concentrations well below published LC50 concentrations. Only unexposed tadpoles significantly avoided predator cues. Copper and imidacloprid reduced swimming speed and distance, and escape responses, while increasing erratic swimming. We observed an interactive effect of imidacloprid and copper on erratic swimming, but in general imidacloprid and copper did not act synergistically. Our results suggest that as contaminants enter waterbodies, tadpoles will suffer considerable direct mortality, reduced foraging capacity, and increased susceptibility to predation. Our results provide the first evidence of imidacloprid affecting amphibian behaviour, and highlight both the adverse effects of copper and imidacloprid, and the importance of exploring the effect of multiple contaminants simultaneously. Copyright © 2018 Elsevier Inc. All rights reserved.

Uncovering Patterns of Inter-Urban Trip and Spatial Interaction from Social Media Check-In Data

PubMed Central

Liu, Yu; Sui, Zhengwei; Kang, Chaogui; Gao, Yong

2014-01-01

The article revisits spatial interaction and distance decay from the perspective of human mobility patterns and spatially-embedded networks based on an empirical data set. We extract nationwide inter-urban movements in China from a check-in data set that covers half a million individuals within 370 cities to analyze the underlying patterns of trips and spatial interactions. By fitting the gravity model, we find that the observed spatial interactions are governed by a power law distance decay effect. The obtained gravity model also closely reproduces the exponential trip displacement distribution. The movement of an individual, however, may not obey the same distance decay effect, leading to an ecological fallacy. We also construct a spatial network where the edge weights denote the interaction strengths. The communities detected from the network are spatially cohesive and roughly consistent with province boundaries. We attribute this pattern to different distance decay parameters between intra-province and inter-province trips. PMID:24465849

Uncovering patterns of inter-urban trip and spatial interaction from social media check-in data.

PubMed

Liu, Yu; Sui, Zhengwei; Kang, Chaogui; Gao, Yong

2014-01-01

The article revisits spatial interaction and distance decay from the perspective of human mobility patterns and spatially-embedded networks based on an empirical data set. We extract nationwide inter-urban movements in China from a check-in data set that covers half a million individuals within 370 cities to analyze the underlying patterns of trips and spatial interactions. By fitting the gravity model, we find that the observed spatial interactions are governed by a power law distance decay effect. The obtained gravity model also closely reproduces the exponential trip displacement distribution. The movement of an individual, however, may not obey the same distance decay effect, leading to an ecological fallacy. We also construct a spatial network where the edge weights denote the interaction strengths. The communities detected from the network are spatially cohesive and roughly consistent with province boundaries. We attribute this pattern to different distance decay parameters between intra-province and inter-province trips.

The building-up of social relationships: behavioural types, social networks and cooperative breeding in a cichlid

PubMed Central

Schürch, Roger; Rothenberger, Susan; Heg, Dik

2010-01-01

Consistent individual differences in behavioural types may not only cause variation in life-history decisions, but may also affect the choice of social partners and sociality in general. Here, we tested whether and how behavioural type influences the establishment of social ties using the cooperatively breeding cichlid, Neolamprologus pulcher. In a habitat saturation experiment with individuals pre-tested for behavioural type, we first analysed whether behavioural type affected the likelihood of settlement (i.e. social status), group sizes, and the types of dominant and subordinate individuals accepted as group members. Corrected for effects of body size and sex, the behavioural type did not affect settlement. However, bold dominant males only accepted smaller females, and grouped with bold subordinates, while shy dominant males accepted larger females than themselves, and grouped with shy subordinates. Second, we analysed the relationships between behavioural type and the aggressiveness or affiliation social network. Behavioural type significantly affected the number and quality of connections within the two networks. We show that behavioural types affect group composition, social networks and status achieved, in interaction with body size. Thus, the interactions within groups may depend not only on age, size and sex, but also on the behavioural type of the individuals involved. PMID:21078660

Negative Symptoms and Avoidance of Social Interaction: A Study of Non-Verbal Behaviour.

PubMed

Worswick, Elizabeth; Dimic, Sara; Wildgrube, Christiane; Priebe, Stefan

2018-01-01

Non-verbal behaviour is fundamental to social interaction. Patients with schizophrenia display an expressivity deficit of non-verbal behaviour, exhibiting behaviour that differs from both healthy subjects and patients with different psychiatric diagnoses. The present study aimed to explore the association between non-verbal behaviour and symptom domains, overcoming methodological shortcomings of previous studies. Standardised interviews with 63 outpatients diagnosed with schizophrenia were videotaped. Symptoms were assessed using the Clinical Assessment Interview for Negative Symptoms (CAINS), the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale. Independent raters later analysed the videos for non-verbal behaviour, using a modified version of the Ethological Coding System for Interviews (ECSI). Patients with a higher level of negative symptoms displayed significantly fewer prosocial (e.g., nodding and smiling), gesture, and displacement behaviours (e.g., fumbling), but significantly more flight behaviours (e.g., looking away, freezing). No gender differences were found, and these associations held true when adjusted for antipsychotic medication dosage. Negative symptoms are associated with both a lower level of actively engaging non-verbal behaviour and an increased active avoidance of social contact. Future research should aim to identify the mechanisms behind flight behaviour, with implications for the development of treatments to improve social functioning. © 2017 S. Karger AG, Basel.

A Specific Pathway Can Be Identified between Genetic Characteristics and Behaviour Profiles in Prader-Willi Syndrome via Cognitive, Environmental and Physiological Mechanisms

ERIC Educational Resources Information Center

Woodcock, K. A.; Oliver, C.; Humphreys, G. W.

2009-01-01

Background: Behavioural phenotypes associated with genetic syndromes have been extensively investigated in order to generate rich descriptions of phenomenology, determine the degree of specificity of behaviours for a particular syndrome, and examine potential interactions between genetic predispositions for behaviour and environmental influences.…

Correlates of Maternal Behaviours in Mothers of Children with Fragile X Syndrome

ERIC Educational Resources Information Center

Wheeler, Anne; Hatton, Deborah; Reichardt, Alison; Bailey, Don

2007-01-01

Background: The behaviours of 24 mothers of children with fragile X syndrome (FXS) with their affected children were examined during planned observations in their homes. The goal of this study was to describe concurrent maternal interactive behaviour and the factors that influence the type and frequency of these behaviours within this group.…

Multicriteria decision model for retrofitting existing buildings

NASA Astrophysics Data System (ADS)

Bostenaru Dan, B.

2003-04-01

In this paper a model to decide which buildings from an urban area should be retrofitted is presented. The model has been cast into existing ones by choosing the decision rule, criterion weighting and decision support system types most suitable for the spatial problem of reducing earthquake risk in urban areas, considering existing spatial multiatributive and multiobjective decision methods and especially collaborative issues. Due to the participative character of the group decision problem "retrofitting existing buildings" the decision making model is based on interactivity. Buildings have been modeled following the criteria of spatial decision support systems. This includes identifying the corresponding spatial elements of buildings according to the information needs of actors from different sphaeres like architects, construction engineers and economists. The decision model aims to facilitate collaboration between this actors. The way of setting priorities interactivelly will be shown, by detailing the two phases: judgemental and computational, in this case site analysis, collection and evaluation of the unmodified data and converting survey data to information with computational methods using additional expert support. Buildings have been divided into spatial elements which are characteristic for the survey, present typical damages in case of an earthquake and are decisive for a better seismic behaviour in case of retrofitting. The paper describes the architectural and engineering characteristics as well as the structural damage for constuctions of different building ages on the example of building types in Bucharest, Romania in compressible and interdependent charts, based on field observation, reports from the 1977 earthquake and detailed studies made by the author together with a local engineer for the EERI Web Housing Encyclopedia. On this base criteria for setting priorities flow into the expert information contained in the system.

Toward a Spatial Perspective on Business Sustainability: The Role of Central Urban and Environmentally Sensitive Areas in Energy Corporates’ Green Behaviours

NASA Astrophysics Data System (ADS)

Wang, Teng; Liu, Zongrui; Zhou, Li

2018-02-01

As one of the most concerned topics in strategic management research, the motivations of energy corporates’ green behaviours are extensively explored by scholars, however, only a few noticed the role of geographic antecedents. To bridge this gap, we argue that energy firms’ green behaviours will be greatly predicted by its location, more specifically, proximity to environmentally sensitive areas and central urban areas. Draw on neo-institutional theory and stakeholder theory, we argue that institutional forces mediate the links between energy corporates’ green behaviours and proximities, while different proximity affects via different institutional logics. The results are discussed along with managerial implications.

Potential clinical relevance of the 'little brain' on the mammalian heart.

PubMed

Armour, J A

2008-02-01

It is hypothesized that the heart possesses a nervous system intrinsic to it that represents the final relay station for the co-ordination of regional cardiac indices. This 'little brain' on the heart is comprised of spatially distributed sensory (afferent), interconnecting (local circuit) and motor (adrenergic and cholinergic efferent) neurones that communicate with others in intrathoracic extracardiac ganglia, all under the tonic influence of central neuronal command and circulating catecholamines. Neurones residing from the level of the heart to the insular cortex form temporally dependent reflexes that control overlapping, spatially determined cardiac indices. The emergent properties that most of its components display depend primarily on sensory transduction of the cardiovascular milieu. It is further hypothesized that the stochastic nature of such neuronal interactions represents a stabilizing feature that matches cardiac output to normal corporal blood flow demands. Thus, with regard to cardiac disease states, one must consider not only cardiac myocyte dysfunction but also the fact that components within this neuroaxis may interact abnormally to alter myocyte function. This review emphasizes the stochastic behaviour displayed by most peripheral cardiac neurones, which appears to be a consequence of their predominant cardiac chemosensory inputs, as well as their complex functional interconnectivity. Despite our limited understanding of the whole, current data indicate that the emergent properties displayed by most neurones comprising the cardiac neuroaxis will have to be taken into consideration when contemplating the targeting of its individual components if predictable, long-term therapeutic benefits are to accrue.

Modelling and testing the x-ray performance of CCD and CMOS APS detectors using numerical finite element simulations

NASA Astrophysics Data System (ADS)

Weatherill, Daniel P.; Stefanov, Konstantin D.; Greig, Thomas A.; Holland, Andrew D.

2014-07-01

Pixellated monolithic silicon detectors operated in a photon-counting regime are useful in spectroscopic imaging applications. Since a high energy incident photon may produce many excess free carriers upon absorption, both energy and spatial information can be recovered by resolving each interaction event. The performance of these devices in terms of both the energy and spatial resolution is in large part determined by the amount of diffusion which occurs during the collection of the charge cloud by the pixels. Past efforts to predict the X-ray performance of imaging sensors have used either analytical solutions to the diffusion equation or simplified monte carlo electron transport models. These methods are computationally attractive and highly useful but may be complemented using more physically detailed models based on TCAD simulations of the devices. Here we present initial results from a model which employs a full transient numerical solution of the classical semiconductor equations to model charge collection in device pixels under stimulation from initially Gaussian photogenerated charge clouds, using commercial TCAD software. Realistic device geometries and doping are included. By mapping the pixel response to different initial interaction positions and charge cloud sizes, the charge splitting behaviour of the model sensor under various illuminations and operating conditions is investigated. Experimental validation of the model is presented from an e2v CCD30-11 device under varying substrate bias, illuminated using an Fe-55 source.

Negotiating behavioural change: therapists' proposal turns in Cognitive Behavioural Therapy.

PubMed

Ekberg, Katie; Lecouteur, Amanda

2012-01-01

Cognitive behavioural therapy (CBT) is an internationally recognised method for treating depression. However, many of the techniques involved in CBT are accomplished within the therapy interaction in diverse ways, and with varying consequences for the trajectory of therapy session. This paper uses conversation analysis to examine some standard ways in which therapists propose suggestions for behavioural change to clients attending CBT sessions for depression in Australia. Therapists' proposal turns displayed their subordinate epistemic authority over the matter at hand, and emphasised a high degree of optionality on behalf of the client in accepting their suggestions. This practice was routinely accomplished via three standard proposal turns: (1) hedged recommendations; (2) interrogatives; and (3) information-giving. These proposal turns will be examined in relation to the negotiation of behavioural change, and the implications for CBT interactions between therapist and client will be discussed.

Late-time behaviour of the Einstein–Boltzmann system with a positive cosmological constant

NASA Astrophysics Data System (ADS)

Lee, Ho; Nungesser, Ernesto

2018-01-01

In this paper we study the Einstein–Boltzmann system for Israel particles with a positive cosmological constant. We consider spatially homogeneous solutions of all Bianchi types except type IX and obtain future global existence and the asymptotic behaviour of solutions to the Einstein–Boltzmann system. The result shows that the solutions converge to the de Sitter solution at late times.

Interactions between dopamine and oxytocin in the control of sexual behaviour.

PubMed

Baskerville, Tracey A; Douglas, Alison J

2008-01-01

Dopamine and oxytocin are two key neuromodulators involved in reproductive behaviours, such as mating and maternal care. Much evidence underlies their separate roles in such behaviours, but particularly in sexual behaviour. It is generally believed that central dopaminergic and oxytocinergic systems work together to regulate the expression of penile erection, but relatively little is known regarding how they interact. Thus, this review aims to discuss neuroanatomical proof, neuromodulator secretory profiles in the hypothalamus and behavioural pharmacological evidence which support a dopamine-oxytocin link in three hypothalamic nuclei that have been implicated in sexual behaviour, namely the medial preoptic nucleus, supraoptic nucleus and paraventricular nucleus (PVN). We also aim to provide an overview of potential dopamine-mediated transduction pathways that occur within these nuclei and are correlated with the exhibition of penile erection. The PVN provides the most convincing evidence for a dopamine-oxytocin link and it is becoming increasingly apparent that parvocellular oxytocinergic neurons in the PVN, in part, mediate the effects of dopamine to elicit penile erection. However, while we show that oxytocin neurons express dopamine receptors, other evidence on whether dopaminergic activation of PVN oxytocin cells involves a direct and/or indirect mechanism is inconclusive and further evidence is required to establish whether the two systems interact synergistically or sequentially in the regulation of penile erection.

Interaction of personality traits with social deprivation in determining mental wellbeing and health behaviours.

PubMed

Packard, Chris J; Cavanagh, Jonathan; McLean, Jennifer S; McConnachie, Alex; Messow, Claudia-Martina; Batty, G David; Burns, Harry; Deans, Kevin A; Sattar, Naveed; Shiels, Paul G; Velupillai, Yoga N; Tannahill, Carol; Millar, Keith

2012-12-01

Associations between personality traits, mental wellbeing and good health behaviours were examined to understand further the social and psychological context of the health divide. In a cross-sectional study, 666 subjects recruited from areas of high and low socioeconomic deprivation had personality traits and mental wellbeing assessed, and lifestyle behaviours quantified. Regression models (using deprivation as a moderating variable) assessed the extent to which personality traits and mental wellbeing predicted health behaviour. Deprived (vs. affluent) subjects exhibited similar levels of extraversion but higher levels of neuroticism and psychoticism, more hopelessness, less sense of coherence, lower self-esteem and lower self-efficacy (all P< 0.001). They ate less fruit and vegetables, smoked more and took less aerobic exercise (all P< 0.001). In the deprived group, personality traits were significantly more important predictors of mental wellbeing than in the least deprived group (P< 0.01 for interaction), and mental wellbeing and extraversion appeared more strongly related to good health behaviours. Persistence of a social divide in health may be related to interactions between personality, mental wellbeing and the adoption of good health behaviours in deprived areas. Effectiveness of health messages may be enhanced by accommodating the variation in the levels of extraversion, neuroticism, hopelessness and sense of coherence.

The Interdependence of Adult Relationship Quality and Parenting Behaviours among African American and European Couples in Rural, Low-Income Communities

PubMed Central

Zvara, Bharathi J.; Mills-Koonce, W. Roger; Heilbron, Nicole; Clincy, Amanda; Cox, Martha J.

2015-01-01

The present study extends the spillover and crossover hypotheses to more carefully model the potential interdependence between parent–parent interaction quality and parent–child interaction quality in family systems. Using propensity score matching, the present study attempted to isolate family processes that are unique across African American and European American couples that are independent of other socio-demographic factors to further clarify how interparental relationships may be related to parenting in a rural, low-income sample. The Actor–Partner Interdependence Model (APIM), a statistical analysis technique that accounts for the interdependence of relationship data, was used with a sample of married and non-married cohabiting African American and European American couples (n = 82 dyads) to evaluate whether mothers' and fathers' observed parenting behaviours are related to their behaviours and their partner's behaviours observed in a couple problem-solving interaction. Findings revealed that interparental withdrawal behaviour, but not conflict behaviour, was associated with less optimal parenting for fathers but not mothers, and specifically so for African American fathers. Our findings support the notion of interdependence across subsystems within the family and suggest that African American fathers may be specifically responsive to variations in interparental relationship quality. PMID:26430390

Niche partitioning of feeding microhabitats produces a unique function for herbivorous rabbitfishes (Perciformes, Siganidae) on coral reefs

NASA Astrophysics Data System (ADS)

Fox, R. J.; Bellwood, D. R.

2013-03-01

Niche theory predicts that coexisting species minimise competition by evolving morphological or behavioural specialisations that allow them to spread out along resource axes such as space, diet and temporal activity. These specialisations define how a species interacts with its environment and, by extension, determine its functional role. Here, we examine the feeding niche of three species of coral reef-dwelling rabbitfishes (Siganidae, Siganus). By comparing aspects of their feeding behaviour (bite location, bite rate, foraging distance) with that of representative species from two other abundant herbivorous fish families, the parrotfishes (Labridae, Scarus) and surgeonfishes (Acanthuridae, Acanthurus), we examine whether rabbitfishes have a feeding niche distinct from other members of the herbivore guild. Measurements of the penetration of the fishes' snouts and bodies into reef concavities when feeding revealed that rabbitfish fed to a greater degree from reef crevices and interstices than other herbivores. There was just a 40 % overlap in the penetration-depth niche between rabbitfish and surgeonfish and a 45 % overlap between rabbitfish and parrotfish, compared with the almost complete niche overlap (95 %) recorded for parrotfish and surgeonfish along this spatial niche axis. Aspects of the morphology of rabbitfish which may contribute to this niche segregation include a comparatively longer, narrower snout and narrower head. Our results suggest that sympatric coexistence of rabbitfish and other reef herbivores is facilitated by segregation along a spatial (and potentially dietary) axis. This segregation results in a unique functional role for rabbitfishes among roving herbivores that of "crevice-browser": a group that specifically feeds on crevice-dwelling algal or benthic organisms. This functional trait may have implications for reef ecosystem processes in terms of controlling the successional development of crevice-based algal communities, reducing their potential to trigger macroalgal outbreaks.

Analysis of Spatio-Temporal Traffic Patterns Based on Pedestrian Trajectories

NASA Astrophysics Data System (ADS)

Busch, S.; Schindler, T.; Klinger, T.; Brenner, C.

2016-06-01

For driver assistance and autonomous driving systems, it is essential to predict the behaviour of other traffic participants. Usually, standard filter approaches are used to this end, however, in many cases, these are not sufficient. For example, pedestrians are able to change their speed or direction instantly. Also, there may be not enough observation data to determine the state of an object reliably, e.g. in case of occlusions. In those cases, it is very useful if a prior model exists, which suggests certain outcomes. For example, it is useful to know that pedestrians are usually crossing the road at a certain location and at certain times. This information can then be stored in a map which then can be used as a prior in scene analysis, or in practical terms to reduce the speed of a vehicle in advance in order to minimize critical situations. In this paper, we present an approach to derive such a spatio-temporal map automatically from the observed behaviour of traffic participants in everyday traffic situations. In our experiments, we use one stationary camera to observe a complex junction, where cars, public transportation and pedestrians interact. We concentrate on the pedestrians trajectories to map traffic patterns. In the first step, we extract trajectory segments from the video data. These segments are then clustered in order to derive a spatial model of the scene, in terms of a spatially embedded graph. In the second step, we analyse the temporal patterns of pedestrian movement on this graph. We are able to derive traffic light sequences as well as the timetables of nearby public transportation. To evaluate our approach, we used a 4 hour video sequence. We show that we are able to derive traffic light sequences as well as time tables of nearby public transportation.

a Geo-Visual Analytics Approach to Biological Shepherding: Modelling Animal Movements and Impacts

NASA Astrophysics Data System (ADS)

Benke, K. K.; Sheth, F.; Betteridge, K.; Pettit, C. J.; Aurambout, J.-P.

2012-07-01

The lamb industry in Victoria is a significant component of the state economy with annual exports in the vicinity of 1 billion. GPS and visualisation tools can be used to monitor grazing animal movements at the farm scale and observe interactions with the environment. Modelling the spatial-temporal movements of grazing animals in response to environmental conditions provides input for the design of paddocks with the aim of improving management procedures, animal performance and animal welfare. The term "biological shepherding" is associated with the re-design of environmental conditions and the analysis of responses from grazing animals. The combination of biological shepherding with geo-visual analytics (geo-spatial data analysis with visualisation) provides a framework for improving landscape design and supports research in grazing behaviour in variable landscapes, heat stress avoidance behaviour during summer months, and modelling excreta distributions (with respect to nitrogen emissions and nitrogen return for fertilising the paddock). Nitrogen losses due to excreta are mainly in the form of gaseous emissions to the atmosphere and leaching into the groundwater. In this study, background and context are provided in the case of biological shepherding and tracking animal movements. Examples are provided of recent applications in regional Australia and New Zealand. Based on experimental data and computer simulation, and using data visualisation and feature extraction, it was demonstrated that livestock excreta are not always randomly located, but concentrated around localised gathering points, sometimes separated by the nature of the excretion. Farmers require information on the nitrogen losses in order to reduce emissions to meet local and international nitrogen leaching and greenhouse gas targets and to improve the efficiency of nutrient management.

Space-time airborne disease mapping applied to detect specific behaviour of varicella in Valencia, Spain.

PubMed

Iftimi, Adina; Montes, Francisco; Santiyán, Ana Míguez; Martínez-Ruiz, Francisco

2015-01-01

Airborne diseases are one of humanity's most feared sicknesses and have regularly caused concern among specialists. Varicella is an airborne disease which usually affects children before the age of 10. Because of its nature, varicella gives rise to interesting spatial, temporal and spatio-temporal patterns. This paper studies spatio-temporal exploratory analysis tools to detect specific behaviour of varicella in the city of Valencia, Spain, from 2008 to 2013. These methods have shown a significant association between the spatial and the temporal component, confirmed by the space-time models applied to the data. High relative risk of varicella is observed in economically disadvantaged regions, areas less involved in vaccination programmes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Urbanisation shapes behavioural responses to a pesticide.

PubMed

Tüzün, Nedim; Debecker, Sara; Op de Beeck, Lin; Stoks, Robby

2015-06-01

The degree of urbanisation is rapidly increasing worldwide. Due to anthropogenic impact, urban populations are exposed to higher levels of contaminants and higher temperatures. Despite this, urbanisation is a largely overlooked spatial component in ecotoxicology. We tested in a common garden rearing experiment whether replicated urban and rural populations of the damselfly Coenagrion puella differ in their vulnerability to sublethal levels of a widespread pesticide, chlorpyrifos, in terms of ecologically relevant behaviours (exploration behaviour, activity, boldness and food intake), and to what extent these patterns are affected by temperature (20 and 24°C). Except boldness, all behaviours were affected by previous pesticide exposure. While the pesticide did not affect exploration behaviour at 20°C, it was associated with increased exploration at 24°C, which may reflect an increased toxicity of chlorpyrifos at higher temperatures. Importantly, rural and urban larvae showed consistently different, sometimes even opposite behavioural responses to pesticide exposure. When exposed to the pesticide, rural larvae decreased activity and food intake at both temperatures; urban larvae instead increased activity at both temperatures and only reduced food intake at the high temperature. This suggests that urban larvae were less affected by the pesticide, which would be consistent with a scenario of local adaptation to higher contaminant levels. Our results highlight that urbanisation may be an important factor to arrive at a spatially explicit ecological risk assessment, and may be an ignored reason why studies on the same species may generate widely different vulnerabilities to pesticides. Copyright © 2015 Elsevier B.V. All rights reserved.

The HealthierU Portal for Supporting Behaviour Change and Diet Programs.

PubMed

Berkovsky, Shlomo; Hendrie, Gilly; Freyne, Jill; Noakes, Manny; Usic, Kathy

2015-01-01

The use of online technologies for supporting participants of behaviour change and diet program is a timely and important research direction. We present HealthierU, adaptive online portal offering a suite of interactive support tools. The portal was evaluated in a 24-week study, which shows that regular reminders trigger increased interaction with the portal. We also analyse interaction patters conducive to weight loss and discuss possible factors of the attrition rates observed in the study.

Requiring collaboration: Hippocampal-prefrontal networks needed in spatial working memory and ageing. A multivariate analysis approach.

PubMed

Zancada-Menendez, C; Alvarez-Suarez, P; Sampedro-Piquero, P; Cuesta, M; Begega, A

2017-04-01

Ageing is characterized by a decline in the processes of retention and storage of spatial information. We have examined the behavioural performance of adult rats (3months old) and aged rats (18months old) in a spatial complex task (delayed match to sample). The spatial task was performed in the Morris water maze and consisted of three sessions per day over a period of three consecutive days. Each session consisted of two trials (one sample and retention) and inter-session intervals of 5min. Behavioural results showed that the spatial task was difficult for middle aged group. This worse execution could be associated with impairments of processing speed and spatial information retention. We examined the changes in the neuronal metabolic activity of different brain regions through cytochrome C oxidase histochemistry. Then, we performed MANOVA and Discriminant Function Analyses to determine the functional profile of the brain networks that are involved in the spatial learning of the adult and middle-aged groups. This multivariate analysis showed two principal functional networks that necessarily participate in this spatial learning. The first network was composed of the supramammillary nucleus, medial mammillary nucleus, CA3, and CA1. The second one included the anterior cingulate, prelimbic, and infralimbic areas of the prefrontal cortex, dentate gyrus, and amygdala complex (basolateral l and central subregions). There was a reduction in the hippocampal-supramammilar network in both learning groups, whilst there was an overactivation in the executive network, especially in the aged group. This response could be due to a higher requirement of the executive control in a complex spatial memory task in older animals. Copyright © 2017 Elsevier Inc. All rights reserved.

Lizard movement tracks: variation in path re-use behaviour is consistent with a scent-marking function

PubMed Central

Jackson, Grant; Roddick, John F.; Bull, C. Michael

2016-01-01

Individual movement influences the spatial and social structuring of a population. Animals regularly use the same paths to move efficiently to familiar places, or to patrol and mark home ranges. We found that Australian sleepy lizards (Tiliqua rugosa), a monogamous species with stable pair-bonds, repeatedly used the same paths within their home ranges and investigated whether path re-use functions as a scent-marking behaviour, or whether it is influenced by site familiarity. Lizards can leave scent trails on the substrate when moving through the environment and have a well-developed vomeronasal system to detect and respond to those scents. Path re-use would allow sleepy lizards to concentrate scent marks along these well-used trails, advertising their presence. Hypotheses of mate attraction and mating competition predict that sleepy lizard males, which experience greater intra-sexual competition, mark more strongly. Consistent with those hypotheses, males re-used their paths more than females, and lizards that showed pairing behaviour with individuals of the opposite sex re-used paths more than unpaired lizards, particularly among females. Hinterland marking is most economic when home ranges are large and mobility is low, as is the case in the sleepy lizard. Consistent with this strategy, re-used paths were predominantly located in the inner 50% home range areas. Together, our detailed movement analyses suggest that path re-use is a scent marking behaviour in the sleepy lizard. We also investigated but found less support for alternative explanations of path re-use behaviour, such as site familiarity and spatial knowledge. Lizards established the same number of paths, and used them as often, whether they had occupied their home ranges for one or for more years. We discuss our findings in relation to maintenance of the monogamous mating system of this species, and the spatial and social structuring of the population. PMID:27019790

The investigation of neonatal MK-801 administration and physical environmental enrichment on emotional and cognitive functions in adult Balb/c mice.

PubMed

Akillioglu, Kubra; Babar Melik, Emine; Melik, Enver; Kocahan, Sayad

2012-09-01

N-methyl-D-aspartate (NMDA) receptors play an important role in brain maturation and developmental processes. It is known that growing up in an enriched environment has effects on emotional and cognitive performance. In our study, we evaluated the effects of physically enriched environment on the emotional and cognitive functions of the adult brain in the setting of previous NMDA receptor hypoactivity during the critical developmental period of the nervous system. In this study, NMDA receptor blockade was induced 5-10 days postnatally (PD5-10) using MK-801 in mice Balb/c (twice a day 0.25 mg/kg, for 5 days, intraperitoneal). MK-801 was given to developing mice living in a standard (SE) and an enrichment environment (EE) and once the animals reached adulthood, emotional behaviors were evaluated using an open field test (OF) and an elevated plus maze (EPM) test whereas cognitive processes were evaluated using the Morris water-maze (MWM). The EE group showed decreased locomotor activity (p<0.05) in the OF and increased exploratory behaviour (p<0.01) and decreased fear of heights/anxiety-like behaviour (p<0.05) in the EPM test. The EE had positive effects on spatial learning in the MWM (p<0.05). Blockade of the NMDA receptor increased the fear of height (p<0.05), decreased exploratory behaviour and locomotor activity (p<0.001). Also, it led to decreased spatial learning (p<0.05). The decreases in spatial learning and exploratory behaviours and the increase in fear of heights/anxiety-like behaviour with NMDA receptor blockade was not reversed by EE. NMDA receptor blockade during the critical period of development led to deterioration in the emotional and cognitive processes during adulthood. An enriched environmental did not reverse the deleterious effects of the NMDA receptor blockade on emotional and cognitive functions. Copyright © 2012. Published by Elsevier Inc.

Lizard movement tracks: variation in path re-use behaviour is consistent with a scent-marking function.

PubMed

Leu, Stephan T; Jackson, Grant; Roddick, John F; Bull, C Michael

2016-01-01

Individual movement influences the spatial and social structuring of a population. Animals regularly use the same paths to move efficiently to familiar places, or to patrol and mark home ranges. We found that Australian sleepy lizards (Tiliqua rugosa), a monogamous species with stable pair-bonds, repeatedly used the same paths within their home ranges and investigated whether path re-use functions as a scent-marking behaviour, or whether it is influenced by site familiarity. Lizards can leave scent trails on the substrate when moving through the environment and have a well-developed vomeronasal system to detect and respond to those scents. Path re-use would allow sleepy lizards to concentrate scent marks along these well-used trails, advertising their presence. Hypotheses of mate attraction and mating competition predict that sleepy lizard males, which experience greater intra-sexual competition, mark more strongly. Consistent with those hypotheses, males re-used their paths more than females, and lizards that showed pairing behaviour with individuals of the opposite sex re-used paths more than unpaired lizards, particularly among females. Hinterland marking is most economic when home ranges are large and mobility is low, as is the case in the sleepy lizard. Consistent with this strategy, re-used paths were predominantly located in the inner 50% home range areas. Together, our detailed movement analyses suggest that path re-use is a scent marking behaviour in the sleepy lizard. We also investigated but found less support for alternative explanations of path re-use behaviour, such as site familiarity and spatial knowledge. Lizards established the same number of paths, and used them as often, whether they had occupied their home ranges for one or for more years. We discuss our findings in relation to maintenance of the monogamous mating system of this species, and the spatial and social structuring of the population.

The Rules Grid: Helping Children with Social Communication and Interaction Needs Manage Social Complexity

ERIC Educational Resources Information Center

Devlin, Niall

2009-01-01

This article introduces a new practical visual approach, the Rules Grid, to support children who have social communication and interaction needs. The Rules Grid involves a system whereby behaviours of concern can be broken down into smaller behavioural manifestations which in turn lead not only to problem identification and specification, but…

Interaction Processes as a Mediating Factor between Children's Externalized Behaviour Difficulties and Engagement in Preschool

ERIC Educational Resources Information Center

Sjöman, Madeleine; Granlund, Mats; Almqvist, Lena

2016-01-01

This study examined social interaction as a mediator between externalized behaviour difficulties and children's engagement in preschool. Data from 663 children (340 boys), aged 18-71 months, were collected at 81 Swedish preschool units in six municipalities to test a path model that included child, teacher, and child groups. The results indicated…

A Culturally-Adaptive Iranian Version of the Questionnaire on Teacher Interaction to Investigate English Teachers' Interpersonal Behaviour

ERIC Educational Resources Information Center

Ahmadi Safa, Mohammad; Doosti, Mehdi

2017-01-01

We investigated Iranian secondary-school English teachers' interpersonal behaviour with a validated culturally-adaptive Iranian version of the Questionnaire on Teacher Interaction. Data were collected from 971 Iranian secondary-school students (398 students participated in the pilot study and 573 students in the main study) and 55 Iranian…

Talk with Me: Student Behaviours and Pronoun Use as Indicators of Discourse Health across Facilitation Methods

ERIC Educational Resources Information Center

Epp, Carrie Demmans; Phirangee, Krystle; Hewitt, Jim

2017-01-01

Identifying which online behaviours and interactions are associated with student perceptions of being supported will enable a deeper understanding of how those activities contribute to learning experiences. Student language is one aspect of their interaction in need of greater exploration within discourse-based online learning environments. As a…

Linking foraging behaviour to physical oceanographic structures: Southern elephant seals and mesoscale eddies east of Kerguelen Islands

NASA Astrophysics Data System (ADS)

Dragon, Anne-Cecile; Monestiez, P.; Bar-Hen, A.; Guinet, C.

2010-10-01

In the Southern Ocean, mesoscale features, such as fronts and eddies, have been shown to have a significant impact in structuring and enhancing primary productivity. They are therefore likely to influence the spatial structure of prey fields and play a key role in the creation of preferred foraging regions for oceanic top-predators. Optimal foraging theory predicts that predators should adjust their movement behaviour in relation to prey density. While crossing areas with sufficient prey density, we expect predators would change their behaviour by, for instance, decreasing their speed and increasing their turning frequency. Diving predators would as well increase the useful part of their dive i.e. increase bottom-time thereby increasing the fraction of time spent capturing prey. Southern elephant seals from the Kerguelen population have several foraging areas: in Antarctic waters, on the Kerguelen Plateau and in the interfrontal zone between the Subtropical and Polar Fronts. This study investigated how the movement and diving behaviour of 22 seals equipped with satellite-relayed data loggers changed in relation to mesoscale structures typical of the interfrontal zone. We studied the links between oceanographic variables including temperature and sea level anomalies, and diving and movement behaviour such as displacement speed, diving duration and bottom-time. Correlation coefficients between each of the time series were calculated and their significance tested with a parametric bootstrap. We focused on oceanographic changes, both temporal and spatial, occurring during behavioural transitions in order to clarify the connections between the behaviour and the marine environment of the animals. We showed that a majority of seals displayed a specific foraging behaviour related to the presence of both cyclonic and anticyclonic eddies. We characterized mesoscale oceanographic zones as either favourable or unfavourable based on the intensity of foraging activity as identified by the behavioural variables. Our findings highlight the importance of mesoscale features for top-predators’ behaviour and introduce a new approach for evaluating the importance to the seals of the origin and intensity of these features.

The Things You Do: Internal Models of Others’ Expected Behaviour Guide Action Observation

PubMed Central

Schenke, Kimberley C.; Wyer, Natalie A.; Bach, Patric

2016-01-01

Predictions allow humans to manage uncertainties within social interactions. Here, we investigate how explicit and implicit person models–how different people behave in different situations–shape these predictions. In a novel action identification task, participants judged whether actors interacted with or withdrew from objects. In two experiments, we manipulated, unbeknownst to participants, the two actors action likelihoods across situations, such that one actor typically interacted with one object and withdrew from the other, while the other actor showed the opposite behaviour. In Experiment 2, participants additionally received explicit information about the two individuals that either matched or mismatched their actual behaviours. The data revealed direct but dissociable effects of both kinds of person information on action identification. Implicit action likelihoods affected response times, speeding up the identification of typical relative to atypical actions, irrespective of the explicit knowledge about the individual’s behaviour. Explicit person knowledge, in contrast, affected error rates, causing participants to respond according to expectations instead of observed behaviour, even when they were aware that the explicit information might not be valid. Together, the data show that internal models of others’ behaviour are routinely re-activated during action observation. They provide first evidence of a person-specific social anticipation system, which predicts forthcoming actions from both explicit information and an individuals’ prior behaviour in a situation. These data link action observation to recent models of predictive coding in the non-social domain where similar dissociations between implicit effects on stimulus identification and explicit behavioural wagers have been reported. PMID:27434265

β-Ocimene, a Key Floral and Foliar Volatile Involved in Multiple Interactions between Plants and Other Organisms.

PubMed

Farré-Armengol, Gerard; Filella, Iolanda; Llusià, Joan; Peñuelas, Josep

2017-07-13

β-Ocimene is a very common plant volatile released in important amounts from the leaves and flowers of many plant species. This acyclic monoterpene can play several biological functions in plants, by potentially affecting floral visitors and also by mediating defensive responses to herbivory. The ubiquity and high relative abundance of β-ocimene in the floral scents of species from most plant families and from different pollination syndromes (ranging from generalism to specialism) strongly suggest that this terpenoid may play an important role in the attraction of pollinators to flowers. We compiled abundant evidence from published studies that supports β-ocimene as a generalist attractant of a wide spectrum of pollinators. We found no studies testing behavioural responses of pollinators to β-ocimene, that could directly demonstrate or deny the function of β-ocimene in pollinator attraction; but several case studies support that the emissions of β-ocimene in flowers of different species follow marked temporal and spatial patterns of emission, which are typical from floral volatile organic compound (VOC) emissions that are involved in pollinator attraction. Furthermore, important β-ocimene emissions are induced from vegetative plant tissues after herbivory in many species, which have relevant functions in the establishment of tritrophic interactions. We thus conclude that β-ocimene is a key plant volatile with multiple relevant functions in plants, depending on the organ and the time of emission. Experimental behavioural studies on pure β-ocimene conducted with pollinating insects will be necessary to prove the assumptions made here.

Spectral enstrophy budget in a shear-less flow with turbulent/non-turbulent interface

NASA Astrophysics Data System (ADS)

Cimarelli, Andrea; Cocconi, Giacomo; Frohnapfel, Bettina; De Angelis, Elisabetta

2015-12-01

A numerical analysis of the interaction between decaying shear free turbulence and quiescent fluid is performed by means of global statistical budgets of enstrophy, both, at the single-point and two point levels. The single-point enstrophy budget allows us to recognize three physically relevant layers: a bulk turbulent region, an inhomogeneous turbulent layer, and an interfacial layer. Within these layers, enstrophy is produced, transferred, and finally destroyed while leading to a propagation of the turbulent front. These processes do not only depend on the position in the flow field but are also strongly scale dependent. In order to tackle this multi-dimensional behaviour of enstrophy in the space of scales and in physical space, we analyse the spectral enstrophy budget equation. The picture consists of an inviscid spatial cascade of enstrophy from large to small scales parallel to the interface moving towards the interface. At the interface, this phenomenon breaks, leaving place to an anisotropic cascade where large scale structures exhibit only a cascade process normal to the interface thus reducing their thickness while retaining their lengths parallel to the interface. The observed behaviour could be relevant for both the theoretical and the modelling approaches to flow with interacting turbulent/nonturbulent regions. The scale properties of the turbulent propagation mechanisms highlight that the inviscid turbulent transport is a large-scale phenomenon. On the contrary, the viscous diffusion, commonly associated with small scale mechanisms, highlights a much richer physics involving small lengths, normal to the interface, but at the same time large scales, parallel to the interface.

Spontaneous assembly of chemically encoded two-dimensional coacervate droplet arrays by acoustic wave patterning

PubMed Central

Tian, Liangfei; Martin, Nicolas; Bassindale, Philip G.; Patil, Avinash J.; Li, Mei; Barnes, Adrian; Drinkwater, Bruce W.; Mann, Stephen

2016-01-01

The spontaneous assembly of chemically encoded, molecularly crowded, water-rich micro-droplets into periodic defect-free two-dimensional arrays is achieved in aqueous media by a combination of an acoustic standing wave pressure field and in situ complex coacervation. Acoustically mediated coalescence of primary droplets generates single-droplet per node micro-arrays that exhibit variable surface-attachment properties, spontaneously uptake dyes, enzymes and particles, and display spatial and time-dependent fluorescence outputs when exposed to a reactant diffusion gradient. In addition, coacervate droplet arrays exhibiting dynamical behaviour and exchange of matter are prepared by inhibiting coalescence to produce acoustically trapped lattices of droplet clusters that display fast and reversible changes in shape and spatial configuration in direct response to modulations in the acoustic frequencies and fields. Our results offer a novel route to the design and construction of ‘water-in-water' micro-droplet arrays with controllable spatial organization, programmable signalling pathways and higher order collective behaviour. PMID:27708286

Polaritonic Rabi and Josephson Oscillations

PubMed Central

Rahmani, Amir; Laussy, Fabrice P.

2016-01-01

The dynamics of coupled condensates is a wide-encompassing problem with relevance to superconductors, BECs in traps, superfluids, etc. Here, we provide a unified picture of this fundamental problem that includes i) detuning of the free energies, ii) different self-interaction strengths and iii) finite lifetime of the modes. At such, this is particularly relevant for the dynamics of polaritons, both for their internal dynamics between their light and matter constituents, as well as for the more conventional dynamics of two spatially separated condensates. Polaritons are short-lived, interact only through their material fraction and are easily detuned. At such, they bring several variations to their atomic counterpart. We show that the combination of these parameters results in important twists to the phenomenology of the Josephson effect, such as the behaviour of the relative phase (running or oscillating) or the occurence of self-trapping. We undertake a comprehensive stability analysis of the fixed points on a normalized Bloch sphere, that allows us to provide a generalized criterion to identify the Rabi and Josephson regimes in presence of detuning and decay. PMID:27452872

Uncertainty about social interactions leads to the evolution of social heuristics.

PubMed

van den Berg, Pieter; Wenseleers, Tom

2018-05-31

Individuals face many types of social interactions throughout their lives, but they often cannot perfectly assess what the consequences of their actions will be. Although it is known that unpredictable environments can profoundly affect the evolutionary process, it remains unclear how uncertainty about the nature of social interactions shapes the evolution of social behaviour. Here, we present an evolutionary simulation model, showing that even intermediate uncertainty leads to the evolution of simple cooperation strategies that disregard information about the social interaction ('social heuristics'). Moreover, our results show that the evolution of social heuristics can greatly affect cooperation levels, nearly doubling cooperation rates in our simulations. These results provide new insight into why social behaviour, including cooperation in humans, is often observed to be seemingly suboptimal. More generally, our results show that social behaviour that seems maladaptive when considered in isolation may actually be well-adapted to a heterogeneous and uncertain world.

Focal adhesion kinase (FAK) perspectives in mechanobiology: implications for cell behaviour.

PubMed

Tomakidi, Pascal; Schulz, Simon; Proksch, Susanne; Weber, Wilfried; Steinberg, Thorsten

2014-09-01

Mechanobiology is a scientific interface discipline emerging from engineering and biology. With regard to tissue-regenerative cell-based strategies, mechanobiological concepts, including biomechanics as a target for cell and human mesenchymal stem cell behaviour, are on the march. Based on the periodontium as a paradigm, this mini-review discusses the key role of focal-adhesion kinase (FAK) in mechanobiology, since it is involved in mediating the transformation of environmental biomechanical signals into cell behavioural responses via mechanotransducing signalling cascades. These processes enable cells to adjust quickly to environmental cues, whereas adjustment itself relies on the specific intramolecular phosphorylation of FAK tyrosine residues and the multiple interactions of FAK with distinct partners. Furthermore, interaction-triggered mechanotransducing pathways govern the dynamics of focal adhesion sites and cell behaviour. Facets of behaviour not only include cell spreading and motility, but also proliferation, differentiation and apoptosis. In translational terms, identified and characterized biomechanical parameters can be incorporated into innovative concepts of cell- and tissue-tailored clinically applied biomaterials controlling cell behaviour as desired.

Behavioural phenotypes predict disease susceptibility and infectiousness

PubMed Central

Araujo, Alessandra; Kirschman, Lucas

2016-01-01

Behavioural phenotypes may provide a means for identifying individuals that disproportionally contribute to disease spread and epizootic outbreaks. For example, bolder phenotypes may experience greater exposure and susceptibility to pathogenic infection because of distinct interactions with conspecifics and their environment. We tested the value of behavioural phenotypes in larval amphibians for predicting ranavirus transmission in experimental trials. We found that behavioural phenotypes characterized by latency-to-food and swimming profiles were predictive of disease susceptibility and infectiousness defined as the capacity of an infected host to transmit an infection by contacts. While viral shedding rates were positively associated with transmission, we also found an inverse relationship between contacts and infections. Together these results suggest intrinsic traits that influence behaviour and the quantity of pathogens shed during conspecific interactions may be an important contributor to ranavirus transmission. These results suggest that behavioural phenotypes provide a means to identify individuals more likely to spread disease and thus give insights into disease outbreaks that threaten wildlife and humans. PMID:27555652

Behavioural phenotypes predict disease susceptibility and infectiousness.

PubMed

Araujo, Alessandra; Kirschman, Lucas; Warne, Robin W

2016-08-01

Behavioural phenotypes may provide a means for identifying individuals that disproportionally contribute to disease spread and epizootic outbreaks. For example, bolder phenotypes may experience greater exposure and susceptibility to pathogenic infection because of distinct interactions with conspecifics and their environment. We tested the value of behavioural phenotypes in larval amphibians for predicting ranavirus transmission in experimental trials. We found that behavioural phenotypes characterized by latency-to-food and swimming profiles were predictive of disease susceptibility and infectiousness defined as the capacity of an infected host to transmit an infection by contacts. While viral shedding rates were positively associated with transmission, we also found an inverse relationship between contacts and infections. Together these results suggest intrinsic traits that influence behaviour and the quantity of pathogens shed during conspecific interactions may be an important contributor to ranavirus transmission. These results suggest that behavioural phenotypes provide a means to identify individuals more likely to spread disease and thus give insights into disease outbreaks that threaten wildlife and humans. © 2016 The Author(s).

Staff in Services for People with Intellectual Disabilities: The Impact of Stress on Attributions of Challenging Behaviour

ERIC Educational Resources Information Center

Rose, D.; Rose, J.

2005-01-01

Background: There is a lack of a conceptual framework as to how stress and attribution variables interact and influence staff behaviour in response to challenging behaviour. To address this, a model is tested examining the impact of stress on attributions of challenging behaviour within Weiner's model of helping. Method: A total of 107 staff…

A general practice-based study of the relationship between indicators of mental illness and challenging behaviour among adults with intellectual disabilities.

PubMed

Felce, D; Kerr, M; Hastings, R P

2009-03-01

Existing studies tend to show a positive association between mental illness and challenging behaviour among adults with intellectual disabilities (ID). However, whether the association is direct or artefactual is less clear. The purpose was to explore the association between psychiatric status and level of challenging behaviour, while controlling for adaptive behaviour and occurrence of autistic spectrum disorders. Data were collected on the age, gender, adaptive and challenging behaviour, social impairment and psychiatric status of 312 adults with ID. Participants were divided according to psychiatric status, group equivalence in adaptive behaviour and the presence of autistic spectrum disorders achieved, and differences in challenging behaviour explored. In addition, multiple regression was used to examine the association between psychiatric status and challenging behaviour after controlling for other participant characteristics and to test whether the interaction between psychiatric status and adaptive behaviour added significantly to explanation. Challenging behaviour was higher among participants meeting threshold levels on the psychiatric screen. The regression analysis confirmed the association and demonstrated an interaction between total score on the psychiatric screen and level of adaptive behaviour. This moderated effect showed the relationship between psychiatric status and challenging behaviour to be stronger at lower adaptive behaviour. This study reinforces previous findings that psychiatric morbidity among people with ID is associated with higher levels of challenging behaviour and supports predictions that this association is more pronounced for people with severe ID. The precise nature and causal direction of the association requires further clarification. However, the understanding of how psychiatric problems might contribute to challenging behaviour needs to be part of the clinical appreciation of such behaviour.

Nutrition, movement and sleep behaviours: their interactions in pathways to obesity and cardiometabolic diseases.

PubMed

Dulloo, A G; Miles-Chan, J L; Montani, J-P

2017-02-01

Among the multitude of dietary and lifestyle behaviours that have been proposed to contribute to the obesity epidemic, those that have generated considerable research scrutiny in the past decade are centred upon sleep behaviours, sedentary behaviours (sitting or lying while awake) and diminished low-level physical activities of everyday life, with each category of behaviours apparently presenting an independent risk for obesity and/or cardiometabolic diseases. These behaviours are highly complex, operate in synergy with each other, disrupt the link between regulation of the circadian clock and metabolic physiology and impact on various components of daily energy expenditure and feeding behaviours to promote obesity and hinder the outcome of obesity therapy. As such, this behavioural triad (nutrition, movement and sleep) presents plenty of scope for intervention and optimization in the context of body weight regulation and lifestyle-related disease prevention. It is against this background that recent advances relevant to the theme of 'Nutrition, Movement & Sleep Behaviors: their interactions in pathways to obesity and cardiometabolic diseases' are addressed in this overview and the nine review articles in this supplement reporting the proceedings of the 8th Fribourg Obesity Research Conference. © 2017 World Obesity Federation.

Atypical Processing of Gaze Cues and Faces Explains Comorbidity between Autism Spectrum Disorder (ASD) and Attention Deficit/Hyperactivity Disorder (ADHD).

PubMed

Groom, Madeleine J; Kochhar, Puja; Hamilton, Antonia; Liddle, Elizabeth B; Simeou, Marina; Hollis, Chris

2017-05-01

This study investigated the neurobiological basis of comorbidity between autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD). We compared children with ASD, ADHD or ADHD+ASD and typically developing controls (CTRL) on behavioural and electrophysiological correlates of gaze cue and face processing. We measured effects of ASD, ADHD and their interaction on the EDAN, an ERP marker of orienting visual attention towards a spatially cued location and the N170, a right-hemisphere lateralised ERP linked to face processing. We identified atypical gaze cue and face processing in children with ASD and ADHD+ASD compared with the ADHD and CTRL groups. The findings indicate a neurobiological basis for the presence of comorbid ASD symptoms in ADHD. Further research using larger samples is needed.

Social behaviour and collective motion in plant-animal worms.

PubMed

Franks, Nigel R; Worley, Alan; Grant, Katherine A J; Gorman, Alice R; Vizard, Victoria; Plackett, Harriet; Doran, Carolina; Gamble, Margaret L; Stumpe, Martin C; Sendova-Franks, Ana B

2016-02-24

Social behaviour may enable organisms to occupy ecological niches that would otherwise be unavailable to them. Here, we test this major evolutionary principle by demonstrating self-organizing social behaviour in the plant-animal, Symsagittifera roscoffensis. These marine aceol flat worms rely for all of their nutrition on the algae within their bodies: hence their common name. We show that individual worms interact with one another to coordinate their movements so that even at low densities they begin to swim in small polarized groups and at increasing densities such flotillas turn into circular mills. We use computer simulations to: (i) determine if real worms interact socially by comparing them with virtual worms that do not interact and (ii) show that the social phase transitions of the real worms can occur based only on local interactions between and among them. We hypothesize that such social behaviour helps the worms to form the dense biofilms or mats observed on certain sun-exposed sandy beaches in the upper intertidal of the East Atlantic and to become in effect a super-organismic seaweed in a habitat where macro-algal seaweeds cannot anchor themselves. Symsagittifera roscoffensis, a model organism in many other areas in biology (including stem cell regeneration), also seems to be an ideal model for understanding how individual behaviours can lead, through collective movement, to social assemblages. © 2016 The Author(s).

Exploring the influence of cultural orientations on assessment of communication behaviours during patient-practitioner interactions.

PubMed

Wilby, Kyle J; Govaerts, Marjan J B; Austin, Zubin; Dolmans, Diana H J M

2017-03-21

Research has shown that patients' and practitioners' cultural orientations affect communication behaviors and interpretations in cross-cultural patient-practitioner interactions. Little is known about the effect of cultural orientations on assessment of communication behaviors in cross-cultural educational settings. The purpose of this study is to explore cultural orientation as a potential source of assessor idiosyncrasy or between-assessor variability in assessment of communication skills. More specifically, we explored if and how (expert) assessors' valuing of communication behaviours aligned with their cultural orientations (power-distance, masculinity-femininity, uncertainty avoidance, and individualism-collectivism). Twenty-five pharmacist-assessors watched 3 videotaped scenarios (patient-pharmacist interactions) and ranked each on a 5-point global rating scale. Videotaped scenarios demonstrated combinations of well-portrayed and borderline examples of instrumental and affective communication behaviours. We used stimulated recall and verbal protocol analysis to investigate assessors' interpretations and evaluations of communication behaviours. Uttered assessments of communication behaviours were coded as instrumental (task-oriented) or affective (socioemotional) and either positive or negative. Cultural orientations were measured using the Individual Cultural Values Scale. Correlations between cultural orientations and global scores, and frequencies of positive, negative, and total utterances of instrumental and affective behaviours were determined. Correlations were found to be scenario specific. In videos with poor or good performance, no differences were found across cultural orientations. When borderline performance was demonstrated, high power-distance and masculinity were significantly associated with higher global ratings (r = .445, and .537 respectively, p < 0.05) as well as with fewer negative utterances regarding instrumental (task focused) behaviours (r = -.533 and - .529, respectively). Higher masculinity scores were furthermore associated with positive utterances of affective (socioemotional) behaviours (r = .441). Our findings thus confirm cultural orientation as a source of assessor idiosyncrasy and meaningful variations in interpretation of communication behaviours. Interestingly, expert assessors generally agreed on scenarios of good or poor performances but borderline performance was influenced by cultural orientation. Contrary to current practices of assessor and assessment instrument standardization, findings support the use of multiple assessors for patient-practitioner interactions and development of qualitative assessment tools to capture these varying, yet valid, interpretations of performance.

Autistic-like behavioural and neurochemical changes in a mouse model of food allergy.

PubMed

de Theije, Caroline G M; Wu, Jiangbo; Koelink, Pim J; Korte-Bouws, Gerdien A H; Borre, Yuliya; Kas, Martien J H; Lopes da Silva, Sofia; Korte, S Mechiel; Olivier, Berend; Garssen, Johan; Kraneveld, Aletta D

2014-03-15

Food allergy has been suggested to contribute to the expression of psychological and psychiatric traits, including disturbed social behaviour and repetitive behaviour inherent in autism spectrum disorders (ASD). Most research in this field receives little attention, since fundamental evidence showing direct effects of food allergic immune responses on social behaviour is very limited. In the present study, we show that a food allergic reaction to cow's milk protein, induced shortly after weaning, reduced social behaviour and increased repetitive behaviour in mice. This food allergic reaction increased levels of serotonin (5-hydroxytryptamine; 5-HT) and the number of 5-HT positive cells, and decreased levels of 5-hydroxyindoleacetic acid (5-HIAA) in the intestine. Behavioural changes in food allergic mice were accompanied by reduced dopaminergic activity in the prefrontal cortex. Furthermore, neuronal activation (c-Fos expression) was increased in the prefrontal cortex and reduced in the paraventricular nucleus of the hypothalamus after exposure to a social target. We hypothesize that an intestinal allergic response regulates complex, but critical, neuroimmune interactions, thereby affecting brain circuits involved in social interaction, repetitive behaviour and cognition. Together with a genetic predisposition and multiple environmental factors, these effects of allergic immune activation may exacerbate behavioural abnormalities in patients with ASD. Copyright © 2013 Elsevier B.V. All rights reserved.

Masculinized female yellow-bellied marmots initiate more social interactions

PubMed Central

Monclús, Raquel; Cook, Taylor; Blumstein, Daniel T.

2012-01-01

The presence of male siblings in utero influences female morphology and life-history traits because testosterone transferred among foetuses may masculinize females. Similarly, litter sex composition might alter the display of sexually dimorphic behaviour, such as play and allogrooming, since they are modulated by androgens. We explored whether masculinization alters the frequency of play and sociopositive behaviour in female yellow-bellied marmots (Marmota flaviventris). We found that masculinized juvenile females were more likely to initiate play and allogrooming, but yearling females exhibited higher levels of oestrogen-modulated sociopositive behaviours. Additionally, the more they interacted, the greater number of different partners they interacted with. Our results suggest that masculinization increases the rate of age-dependent social behaviour. This probably works by increasing exploration that predisposes individuals to higher encounter rates. Further support comes from previous findings showing that masculinized females were more likely to disperse. Our study stresses the importance of considering litter sex composition as a fitness modulator. PMID:21880621

The smell of change: warming affects species interactions mediated by chemical information.

PubMed

Sentis, Arnaud; Ramon-Portugal, Felipe; Brodeur, Jacques; Hemptinne, Jean-Louis

2015-10-01

Knowledge of how temperature influences an organism's physiology and behaviour is of paramount importance for understanding and predicting the impacts of climate change on species' interactions. While the behaviour of many organisms is driven by chemical information on which they rely on to detect resources, conspecifics, natural enemies and competitors, the effects of temperature on infochemical-mediated interactions remain largely unexplored. Here, we experimentally show that temperature strongly influences the emission of infochemicals by ladybeetle larvae, which, in turn, modifies the oviposition behaviour of conspecific females. Temperature also directly affects female perception of infochemicals and their oviposition behaviour. Our results suggest that temperature-mediated effects on chemical communication can influence flows across system boundaries (e.g. immigration and emigration) and thus alter the dynamics and stability of ecological networks. We therefore argue that investigating the effects of temperature on chemical communication is a crucial step towards a better understanding of the functioning of ecological communities facing rapid environmental changes. © 2015 John Wiley & Sons Ltd.

Extraversion, neuroticism, immoral judgment and criminal behaviour.

PubMed

Addad, M; Leslau, A

1989-01-01

The present study examines delinquent behaviour by integrating two approaches until now employed separately: Eysnck's theory linking delinquency to extraversion and neuroticism, and Kohlberg's theory of moral development and its connection to moral behaviour. The study analyzes the relations between extraversion, neuroticism and moral judgment, as well as their independent and/or interactive effect upon the development of anti-social behaviour. The relationships are tested by retrospective measurements of personality traits and moral judgment in three groups: delinquency (N = 203), control (N = 82) and comparative (N = 407) groups. Findings show that criminals are higher than control subjects in neuroticism and immoral judgment but not in extraversion. Similar relationships were found between criminals and the comparative group, with one exception: here extraversion was found to be positively related to delinquency, both independently and interactively with neuroticism. The implications of these results for differential development of anti-social behaviour are discussed.

Inflexibility as an interactional phenomenon: Using conversation analysis to re-examine a symptom of autism.

PubMed

Muskett, Tom; Perkins, Mick; Clegg, Judy; Body, Richard

2010-01-01

Many accounts of autism spectrum disorder (ASD) imply that the condition's behavioural 'symptoms' are direct reflexes of underlying deficits. In doing so, however, they invariably overlook the social contexts in which symptomatic behaviours occur and are identified as pathological. This study addresses this issue, using conversation analysis (CA) to examine the emergence of inflexibility, a behavioural trait symptomatic of ASD, during play involving an adult and diagnosed child. We argue that 'inflexibility' is the product of the child's strategic attempts to retain control over the unfolding interaction, within a context where such attempts breach normative expectations about adult-child play. Furthermore, it demonstrates that the adult does not resist these attempts, on occasion even explicitly providing opportunity for subsequent inflexibility. This challenges the assumption that ASD's behavioural profile solely represents the endpoint of underlying deficit, and demonstrates how 'non-impaired' speakers can be implicated in the manifestation of symptomatic behaviours.

Bee++: An Object-Oriented, Agent-Based Simulator for Honey Bee Colonies

PubMed Central

Betti, Matthew; LeClair, Josh; Wahl, Lindi M.; Zamir, Mair

2017-01-01

We present a model and associated simulation package (www.beeplusplus.ca) to capture the natural dynamics of a honey bee colony in a spatially-explicit landscape, with temporally-variable, weather-dependent parameters. The simulation tracks bees of different ages and castes, food stores within the colony, pollen and nectar sources and the spatial position of individual foragers outside the hive. We track explicitly the intake of pesticides in individual bees and their ability to metabolize these toxins, such that the impact of sub-lethal doses of pesticides can be explored. Moreover, pathogen populations (in particular, Nosema apis, Nosema cerenae and Varroa mites) have been included in the model and may be introduced at any time or location. The ability to study interactions among pesticides, climate, biodiversity and pathogens in this predictive framework should prove useful to a wide range of researchers studying honey bee populations. To this end, the simulation package is written in open source, object-oriented code (C++) and can be easily modified by the user. Here, we demonstrate the use of the model by exploring the effects of sub-lethal pesticide exposure on the flight behaviour of foragers. PMID:28287445

A review of game-theoretic models of road user behaviour.

PubMed

Elvik, Rune

2014-01-01

This paper reviews game-theoretic models that have been developed to explain road user behaviour in situations where road users interact with each other. The paper includes the following game-theoretic models: 1.A general model of the interaction between road users and their possible reaction to measures improving safety (behavioural adaptation).2.Choice of vehicle size as a Prisoners’ dilemma game.3.Speed choice as a co-ordination game.4.Speed compliance as a game between drivers and the police.5.Merging into traffic from an acceleration lane as a mixed-strategy game.6.Choice of level of attention in following situations as an evolutionary game.7.Choice of departure time to avoid congestion as variant of a Prisoners’ dilemma game.8.Interaction between cyclists crossing the road and car drivers.9.Dipping headlights at night well ahead of the point when glare becomes noticeable.10.Choice of evasive action in a situation when cars are on collision course. The models reviewed are different in many respects, but a common feature of the models is that they can explain how informal norms of behaviour can develop among road users and be sustained even if these informal norms violate the formal regulations of the traffic code. Game-theoretic models are not applicable to every conceivable interaction between road users or to situations in which road users choose behaviour without interacting with other road users. Nevertheless, it is likely that game-theoretic models can be applied more widely than they have been until now. Copyright © 2013 Elsevier Ltd. All rights reserved.

Moderating role of the MAOA genotype in antisocial behaviour

PubMed Central

Fergusson, David M.; Boden, Joseph M.; Horwood, L. John; Miller, Allison; Kennedy, Martin A.

2012-01-01

Background Recent studies have examined gene×environment (G×E) interactions involving the monoamine oxidase A (MAOA) gene in moderating the associations between exposure to adversity and antisocial behaviour. The present study examined a novel method for assessing interactions between a single gene and multiple risk factors related to environmental and personal adversity. Aims To test the hypothesis that the presence of the low-activity MAOA genotype was associated with an increased response to a series of risk factors. Method Participants were 399 males from the Christchurch Health and Development Study who had complete data on: (a) MAOA promoter region variable number tandem repeat genotype; (b) antisocial behaviour (criminal offending) to age 30 and convictions to age 21; and (c) maternal smoking during pregnancy, IQ, childhood maltreatment and school failure. Results Poisson regression models were fitted to three antisocial behaviour outcomes (property/violent offending ages 15–30; and convictions ages 17–21), using measures of exposure to adverse childhood circumstances. The analyses revealed consistent evidence of G x E interactions, such that those with the low-activity MAOA variant who were exposed to adversity in childhood were significantly more likely to report offending in late adolescence and early adulthood. Conclusions The present findings add to the evidence suggesting that there is a stable G x E interaction involving MAOA, a range of adverse environmental and personal factors, and antisocial behaviour across the life course. These analyses also demonstrate the utility of using multiple environmental/personal exposures to test G×E interactions. PMID:22297589

Teachers' and students' verbal behaviours during cooperative and small-group learning.

PubMed

Gillies, Robyn M

2006-06-01

Teachers play a critical role in promoting interactions between students and engaging them in the learning process. This study builds on a study by Hertz-Lazarowitz and Shachar (1990) who found that during cooperative learning teachers' verbal behaviours were more helpful to and encouraging of their students' efforts while during whole-class instruction, their verbal behaviours tended to be more authoritarian, rigid, and impersonal. This study seeks to determine if teachers who implement cooperative learning engage in more facilitative learning interactions with their students than teachers who implement group work only. The study also seeks to determine if students in the cooperative groups model their teachers' behaviours and engage in more positive helping interactions with each other than their peers in the group work groups. The study involved 26 teachers and 303 students in Grades 8 to 10 from 4 large high schools in Brisbane, Australia. All teachers agreed to establish cooperative, small-group activities in their classrooms for a unit of work (4 to 6 weeks) once a term for 3 school terms. The teachers were audiotaped twice during these lessons and samples of the students' language, as they worked in their groups, were also collected at the same time. The results show that teachers who implement cooperative learning in their classrooms engage in more mediated-learning interactions and make fewer disciplinary comments than teachers who implement group work only. Furthermore, the students model many of these interactions in their groups. The study shows that when teachers implement cooperative learning, their verbal behaviour is affected by the organizational structure of the classroom.

Mortality, movement and behaviour of native mussels during a planned water-level drawdown in the Upper Mississippi River

USGS Publications Warehouse

Newton, Teresa J.; Zigler, Steven J.; Gray, Brian R.

2015-01-01

Collectively, these data suggest that drawdowns can influence the mortality, movement and behaviour of mussels in the UMR. However, more information on spatial and temporal distributions of mussels is needed to better understand the magnitude of these effects. Results from this study are being used by resource managers to better evaluate the effects of this management tool on native mussel assemblages.

Weakly aggressive behaviour towards nymphs in the cockroach Schultesia nitor (Blattaria: Zetoborinae).

PubMed

Van Baaren, Joan; Deleporte, Pierre; Vimard, Aurélie; Biquand, Véronique; Pierre, Jean-Sebastien

2007-01-01

This paper describes aggressive behaviour in the cockroach Schultesia nitor, a tropical forest species living in bird nests. Young S. nitor nymphs are known to show active dispersal while old nymphs and adults are contrastingly strongly gregarious, a combination of features never observed in other cockroach species. Our laboratory experiments using video recording of confrontations between pairs show that aggressive behaviour towards conspecific nymphs is not exhibited towards nymphs of the species Phoetalia pallida, and thus can be considered species specific in S. nitor. But, it is not kin oriented: the mother and all adults of both sexes in different physiological states exhibit this behaviour as well. Six types of aggressive interactions were discriminated, occurring in age-symmetric pairs of nymphs and adults. Even more frequent aggression was exhibited by adults and last instar nymphs towards younger nymphs of all instars. The frequency of aggressive acts and types of aggressive interactions varied according to sex and size of the two interacting individuals. The possible function and evolution of this behaviour is discussed, with emphasis on the difficulty of interpreting obvious but weak and not kin-biased aggression. 2007 Wiley-Liss, Inc.

Constraints imposed by pollinator behaviour on the ecology and evolution of plant mating systems.

PubMed

Devaux, C; Lepers, C; Porcher, E

2014-07-01

Most flowering plants rely on pollinators for their reproduction. Plant-pollinator interactions, although mutualistic, involve an inherent conflict of interest between both partners and may constrain plant mating systems at multiple levels: the immediate ecological plant selfing rates, their distribution in and contribution to pollination networks, and their evolution. Here, we review experimental evidence that pollinator behaviour influences plant selfing rates in pairs of interacting species, and that plants can modify pollinator behaviour through plastic and evolutionary changes in floral traits. We also examine how theoretical studies include pollinators, implicitly or explicitly, to investigate the role of their foraging behaviour in plant mating system evolution. In doing so, we call for more evolutionary models combining ecological and genetic factors, and additional experimental data, particularly to describe pollinator foraging behaviour. Finally, we show that recent developments in ecological network theory help clarify the impact of community-level interactions on plant selfing rates and their evolution and suggest new research avenues to expand the study of mating systems of animal-pollinated plant species to the level of the plant-pollinator networks. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Host-pathogen interactions in a varying environment: temperature, behavioural fever and fitness.

PubMed Central

Elliot, Sam L; Blanford, Simon; Thomas, Matthew B

2002-01-01

We demonstrate how variable temperatures, mediated by host thermoregulation and behavioural fever, critically affect the interaction between a host (the desert locust, Schistocerca gregaria) and a pathogen (the fungus Metarhizium anisopliae var. acridum). By means of behavioural thermoregulation, infected locusts can raise their body temperatures to fever levels. The adaptive value of this behaviour was examined using three thermal regimes wherein maximum body temperatures achievable were: (i) below, or (ii) at normally preferred temperatures, or were (iii) unrestricted, allowing heightened fever temperatures. All infected locusts ultimately succumbed to disease, with median survival times of 8, 15 and 21 days post-infection, respectively. Crucially, only those locusts able to fever produced viable offspring. This represents, to our knowledge, the first demonstration of the adaptive value of behavioural fever following infection with a naturally occurring pathogen. By contrast, although normal host thermoregulation moderately reduced pathogen reproduction (by 35%), there was no additional negative effect of fever, resulting in an asymmetry in the fitness consequences of fever for the host and the pathogen. The dependency of the host-pathogen interaction upon external abiotic conditions has implications for how virulence and resistance are treated both theoretically and in the management of pests and diseases. PMID:12184830

From global change to a butterfly flapping: biophysics and behaviour affect tropical climate change impacts.

PubMed

Bonebrake, Timothy C; Boggs, Carol L; Stamberger, Jeannie A; Deutsch, Curtis A; Ehrlich, Paul R

2014-10-22

Difficulty in characterizing the relationship between climatic variability and climate change vulnerability arises when we consider the multiple scales at which this variation occurs, be it temporal (from minute to annual) or spatial (from centimetres to kilometres). We studied populations of a single widely distributed butterfly species, Chlosyne lacinia, to examine the physiological, morphological, thermoregulatory and biophysical underpinnings of adaptation to tropical and temperate climates. Microclimatic and morphological data along with a biophysical model documented the importance of solar radiation in predicting butterfly body temperature. We also integrated the biophysics with a physiologically based insect fitness model to quantify the influence of solar radiation, morphology and behaviour on warming impact projections. While warming is projected to have some detrimental impacts on tropical ectotherms, fitness impacts in this study are not as negative as models that assume body and air temperature equivalence would suggest. We additionally show that behavioural thermoregulation can diminish direct warming impacts, though indirect thermoregulatory consequences could further complicate predictions. With these results, at multiple spatial and temporal scales, we show the importance of biophysics and behaviour for studying biodiversity consequences of global climate change, and stress that tropical climate change impacts are likely to be context-dependent. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

The short-term effects of a routine poisoning campaign on the movements and detectability of a social top-predator.

PubMed

Allen, Benjamin L; Engeman, Richard M; Leung, Luke K-P

2014-02-01

Top-predators can be important components of resilient ecosystems, but they are still controlled in many places to mitigate a variety of economic, environmental and/or social impacts. Lethal control is often achieved through the broad-scale application of poisoned baits. Understanding the direct and indirect effects of such lethal control on subsequent movements and behaviour of survivors is an important pre-requisite for interpreting the efficacy and ecological outcomes of top-predator control. In this study, we use GPS tracking collars to investigate the fine-scale and short-term movements of dingoes (Canis lupus dingo and other wild dogs) in response to a routine poison-baiting program as an example of how a common, social top-predator can respond (behaviourally) to moderate levels of population reduction. We found no consistent control-induced differences in home range size or location, daily distance travelled, speed of travel, temporal activity patterns or road/trail usage for the seven surviving dingoes we monitored immediately before and after a typical lethal control event. These data suggest that the spatial behaviour of surviving dingoes was not altered in ways likely to affect their detectability, and if control-induced changes in dingoes' ecological function did occur, these may not be related to altered spatial behaviour or movement patterns.

From global change to a butterfly flapping: biophysics and behaviour affect tropical climate change impacts

PubMed Central

Bonebrake, Timothy C.; Boggs, Carol L.; Stamberger, Jeannie A.; Deutsch, Curtis A.; Ehrlich, Paul R.

2014-01-01

Difficulty in characterizing the relationship between climatic variability and climate change vulnerability arises when we consider the multiple scales at which this variation occurs, be it temporal (from minute to annual) or spatial (from centimetres to kilometres). We studied populations of a single widely distributed butterfly species, Chlosyne lacinia, to examine the physiological, morphological, thermoregulatory and biophysical underpinnings of adaptation to tropical and temperate climates. Microclimatic and morphological data along with a biophysical model documented the importance of solar radiation in predicting butterfly body temperature. We also integrated the biophysics with a physiologically based insect fitness model to quantify the influence of solar radiation, morphology and behaviour on warming impact projections. While warming is projected to have some detrimental impacts on tropical ectotherms, fitness impacts in this study are not as negative as models that assume body and air temperature equivalence would suggest. We additionally show that behavioural thermoregulation can diminish direct warming impacts, though indirect thermoregulatory consequences could further complicate predictions. With these results, at multiple spatial and temporal scales, we show the importance of biophysics and behaviour for studying biodiversity consequences of global climate change, and stress that tropical climate change impacts are likely to be context-dependent. PMID:25165769

Parental prey selection affects risk-taking behaviour and spatial learning in avian offspring

PubMed Central

Arnold, Kathryn E; Ramsay, Scot L; Donaldson, Christine; Adam, Aileen

2007-01-01

Early nutrition shapes life history. Parents should, therefore, provide a diet that will optimize the nutrient intake of their offspring. In a number of passerines, there is an often observed, but unexplained, peak in spider provisioning during chick development. We show that the proportion of spiders in the diet of nestling blue tits, Cyanistes caeruleus, varies significantly with the age of chicks but is unrelated to the timing of breeding or spider availability. Moreover, this parental prey selection supplies nestlings with high levels of taurine particularly at younger ages. This amino acid is known to be both vital and limiting for mammalian development and consequently found in high concentrations in placenta and milk. Based on the known roles of taurine in mammalian brain development and function, we then asked whether by supplying taurine-rich spiders, avian parents influence the stress responsiveness and cognitive function of their offspring. To test this, we provided wild blue tit nestlings with either a taurine supplement or control treatment once daily from the ages of 2–14 days. Then pairs of size- and sex-matched siblings were brought into captivity for behavioural testing. We found that juveniles that had received additional taurine as neonates took significantly greater risks when investigating novel objects than controls. Taurine birds were also more successful at a spatial learning task than controls. Additionally, those individuals that succeeded at a spatial learning task had shown intermediate levels of risk taking. Non-learners were generally very risk-averse controls. Early diet therefore has downstream impacts on behavioural characteristics that could affect fitness via foraging and competitive performance. Fine-scale prey selection is a mechanism by which parents can manipulate the behavioural phenotype of offspring. PMID:17698490

Parental prey selection affects risk-taking behaviour and spatial learning in avian offspring.

PubMed

Arnold, Kathryn E; Ramsay, Scot L; Donaldson, Christine; Adam, Aileen

2007-10-22

Early nutrition shapes life history. Parents should, therefore, provide a diet that will optimize the nutrient intake of their offspring. In a number of passerines, there is an often observed, but unexplained, peak in spider provisioning during chick development. We show that the proportion of spiders in the diet of nestling blue tits, Cyanistes caeruleus, varies significantly with the age of chicks but is unrelated to the timing of breeding or spider availability. Moreover, this parental prey selection supplies nestlings with high levels of taurine particularly at younger ages. This amino acid is known to be both vital and limiting for mammalian development and consequently found in high concentrations in placenta and milk. Based on the known roles of taurine in mammalian brain development and function, we then asked whether by supplying taurine-rich spiders, avian parents influence the stress responsiveness and cognitive function of their offspring. To test this, we provided wild blue tit nestlings with either a taurine supplement or control treatment once daily from the ages of 2-14 days. Then pairs of size- and sex-matched siblings were brought into captivity for behavioural testing. We found that juveniles that had received additional taurine as neonates took significantly greater risks when investigating novel objects than controls. Taurine birds were also more successful at a spatial learning task than controls. Additionally, those individuals that succeeded at a spatial learning task had shown intermediate levels of risk taking. Non-learners were generally very risk-averse controls. Early diet therefore has downstream impacts on behavioural characteristics that could affect fitness via foraging and competitive performance. Fine-scale prey selection is a mechanism by which parents can manipulate the behavioural phenotype of offspring.

Detecting and modelling structures on the micro and the macro scales: Assessing their effects on solute transport behaviour

NASA Astrophysics Data System (ADS)

Haslauer, C. P.; Bárdossy, A.; Sudicky, E. A.

2017-09-01

This paper demonstrates quantitative reasoning to separate the dataset of spatially distributed variables into different entities and subsequently characterize their geostatistical properties, properly. The main contribution of the paper is a statistical based algorithm that matches the manual distinction results. This algorithm is based on measured data and is generally applicable. In this paper, it is successfully applied at two datasets of saturated hydraulic conductivity (K) measured at the Borden (Canada) and the Lauswiesen (Germany) aquifers. The boundary layer was successfully delineated at Borden despite its only mild heterogeneity and only small statistical differences between the divided units. The methods are verified with the more heterogeneous Lauswiesen aquifer K data-set, where a boundary layer has previously been delineated. The effects of the macro- and the microstructure on solute transport behaviour are evaluated using numerical solute tracer experiments. Within the microscale structure, both Gaussian and non-Gaussian models of spatial dependence of K are evaluated. The effects of heterogeneity both on the macro- and the microscale are analysed using numerical tracer experiments based on four scenarios: including or not including the macroscale structures and optimally fitting a Gaussian or a non-Gaussian model for the spatial dependence in the micro-structure. The paper shows that both micro- and macro-scale structures are important, as in each of the four possible geostatistical scenarios solute transport behaviour differs meaningfully.

Localizing the Frequency x Regularity Word Reading Interaction in the Cerebral Cortex

ERIC Educational Resources Information Center

Cummine, Jacqueline; Sarty, Gordon E.; Borowsky, Ron

2010-01-01

The aim of this work is to combine behavioural and functional magnetic resonance imaging (fMRI) data to advance our knowledge of where the Frequency x Regularity interaction on word naming is located in the cerebral cortex. Participants named high and low frequency, regular and exception words in a behavioural lab (Experiment 1) and during an fMRI…

Towards a Framework in Interaction Training for Staff Working with Clients with Intellectual Disabilities and Challenging Behaviour

ERIC Educational Resources Information Center

Willems, A.; Embregts, P.; Hendriks, L.; Bosman, A.

2016-01-01

Background: Training support staff in dealing with challenging behaviour in clients with intellectual disabilities (ID) is needed. The goal of this study is to determine which elements need to be incorporated in a training on staff interactions with these clients, building upon a framework and an interpersonal model. As in functional analysis,…

Collective Behaviour in Video Viewing: A Thermodynamic Analysis of Gaze Position.

PubMed

Burleson-Lesser, Kate; Morone, Flaviano; DeGuzman, Paul; Parra, Lucas C; Makse, Hernán A

2017-01-01

Videos and commercials produced for large audiences can elicit mixed opinions. We wondered whether this diversity is also reflected in the way individuals watch the videos. To answer this question, we presented 65 commercials with high production value to 25 individuals while recording their eye movements, and asked them to provide preference ratings for each video. We find that gaze positions for the most popular videos are highly correlated. To explain the correlations of eye movements, we model them as "interactions" between individuals. A thermodynamic analysis of these interactions shows that they approach a "critical" point such that any stronger interaction would put all viewers into lock-step and any weaker interaction would fully randomise patterns. At this critical point, groups with similar collective behaviour in viewing patterns emerge while maintaining diversity between groups. Our results suggest that popularity of videos is already evident in the way we look at them, and that we maintain diversity in viewing behaviour even as distinct patterns of groups emerge. Our results can be used to predict popularity of videos and commercials at the population level from the collective behaviour of the eye movements of a few viewers.

Quantifying the strength of the associations of prototype perceptions with behaviour, behavioural willingness and intentions: a meta-analysis.

PubMed

van Lettow, Britt; de Vries, Hein; Burdorf, Alex; van Empelen, Pepijn

2016-01-01

Prototypes (i.e., social images representing perceptions of typical persons engaging in or refraining from certain behaviour) have been shown to explain health-related behaviours. The present meta-analysis quantified the strength of the associations of prototype perceptions with health motivation and behaviour. Specifically, the analysis addressed (i) the relationship of prototype favourability (i.e., degree of likability) and similarity (i.e., perceived resemblance to the self) with behaviour, willingness and intentions; (ii) the effect of the interaction between favourability and similarity; and (iii) the extent to which health-risk and health-protective prototypes differed in their association with these outcomes. A total of 80 independent studies were identified based on 69 articles. The results indicated that prototype favourability and similarity were related to behaviour, intentions and willingness with small-to-medium effect sizes (r+ = 0.12-0.43). Direct measures of prototype perceptions generally produced larger effects than indirect measures. The interaction between favourability and similarity produced small-to-large effect sizes (r+ = .22-.54). The results suggest that both health-risk and health-protective prototypes might be useful targets for interventions (r+ = .22-.54). In order to increase health-protective behaviours, intentions and behaviour could be targeted by increasing similarity to health-protective prototypes. Health-risk behaviour might be decreased by targeting willingness by modifying health-risk prototype favourability and similarity.

Enriched environment ameliorates depression-induced cognitive deficits and restores abnormal hippocampal synaptic plasticity.

PubMed

Mahati, K; Bhagya, V; Christofer, T; Sneha, A; Shankaranarayana Rao, B S

2016-10-01

Severe depression compromises structural and functional integrity of the brain and results in impaired learning and memory, maladaptive synaptic plasticity as well as degenerative changes in the hippocampus and amygdala. The precise mechanisms underlying cognitive dysfunctions in depression remain largely unknown. On the other hand, enriched environment (EE) offers beneficial effects on cognitive functions, synaptic plasticity in the hippocampus. However, the effect of EE on endogenous depression associated cognitive dysfunction has not been explored. Accordingly, we have attempted to address this issue by investigating behavioural, structural and synaptic plasticity mechanisms in an animal model of endogenous depression after exposure to enriched environment. Our results demonstrate that depression is associated with impaired spatial learning and enhanced anxiety-like behaviour which is correlated with hypotrophy of the dentate gyrus and amygdalar hypertrophy. We also observed a gross reduction in the hippocampal long-term potentiation (LTP). We report a complete behavioural recovery with reduced indices of anhedonia and behavioural despair, reduced anxiety-like behaviour and improved spatial learning along with a complete restoration of dentate gyrus and amygdalar volumes in depressive rats subjected to EE. Enrichment also facilitated CA3-Schaffer collateral LTP. Our study convincingly proves that depression-induces learning deficits and impairs hippocampal synaptic plasticity. It also highlights the role of environmental stimuli in restoring depression-induced cognitive deficits which might prove vital in outlining more effective strategies to treat major depressive disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

High-sucrose diets in male rats disrupt aspects of decision making tasks, motivation and spatial memory, but not impulsivity measured by operant delay-discounting.

PubMed

Wong, Alanna; Dogra, Vimi R; Reichelt, Amy C

2017-06-01

Excessive consumption of sugar sweetened drinks is proposed to produce functional changes in the hippocampus and prefrontal cortex, leading to perturbations in behavioural control. Impairments in behavioural control have been observed in obese people on tasks that involve making choices, including delay-discounting, indicative of increased impulsivity. In this study we examined the impact of 2h daily access to 10% sucrose (or no sucrose in controls) in young male rats on behavioural tasks reliant on hippocampal function including delay-discounting, T-maze forced choice alternation and place recognition memory, as well as progressive ratio to measure motivation. We observed deficits in place recognition memory and T-maze forced choice alternation, indicative of hippocampal deficits in rats with a history of sucrose consumption. Moreover, rats with a history of sucrose consumption were less motivated to lever press for rewards on a progressive ratio schedule. However, rats with a history of sucrose consumption performed equally to control animals during the delay-discounting task, suggesting that they discounted for reward size over a delay in a manner comparable to control animals. These findings indicate that high-sucrose diets impact on spatial and working memory processes, but do not induce impulsive-like choice behaviours in rats, suggesting that unhealthy diet choices may not influence this aspect of decision-making behaviour. Copyright © 2017 Elsevier B.V. All rights reserved.

FRN and P300 ERP effect modulation in response to feedback sensitivity: the contribution of punishment-reward system (BIS/BAS) and behaviour identification of action.

PubMed

Balconi, Michela; Crivelli, Davide

2010-02-01

Disruption of the sense of being effective and causally determinant in performing an action was explored in the present research by inducing an erroneous external spatial feedback in response to the subject's behaviour. ERPs were recorded from fifteen subjects when they were receiving mismatching/matching feedback information on direction. In addition, subjective sensitivity to the external cues was monitored by Behavioural Inhibition System (BIS) and Behavioural Activation System (BAS) measures, as well as Behaviour Identification process was tested by Behavior Identification Form (BIF). One negative ERP deflections of higher amplitude was revealed in concomitance to false feedback, peaking at about 210ms post-stimulus, more central-posteriorly localized. We supposed that it may represent feedback-error system of which activity might be reflected in FRN, deputed to monitor the unattended feedback furnished by an external system. Moreover, a P3b effect was also observed in great measure for false spatial feedback, more posteriorly (Pz) distributed. According to the context-updating hypothesis, the P3b may reflect the revision of the mental model of the context. BIS showed to be more sensitive to both veridical and false feedback that increased FRN, whereas higher-BAS and BAS-Reward measures revealed an increased proactive attitude to external feedback (higher P3b). Finally, low-level of action representation explained FRN amplitude more than high-level one.

From broadscale patterns to fine-scale processes: habitat structure influences genetic differentiation in the pitcher plant midge across multiple spatial scales.

PubMed

Rasic, Gordana; Keyghobadi, Nusha

2012-01-01

The spatial scale at which samples are collected and analysed influences the inferences that can be drawn from landscape genetic studies. We examined genetic structure and its landscape correlates in the pitcher plant midge, Metriocnemus knabi, an inhabitant of the purple pitcher plant, Sarracenia purpurea, across several spatial scales that are naturally delimited by the midge's habitat (leaf, plant, cluster of plants, bog and system of bogs). We analysed 11 microsatellite loci in 710 M. knabi larvae from two systems of bogs in Algonquin Provincial Park (Canada) and tested the hypotheses that variables related to habitat structure are associated with genetic differentiation in this midge. Up to 54% of variation in individual-based genetic distances at several scales was explained by broadscale landscape variables of bog size, pitcher plant density within bogs and connectivity of pitcher plant clusters. Our results indicate that oviposition behaviour of females at fine scales, as inferred from the spatial locations of full-sib larvae, and spatially limited gene flow at broad scales represent the important processes underlying observed genetic patterns in M. knabi. Broadscale landscape features (bog size and plant density) appear to influence oviposition behaviour of midges, which in turn influences the patterns of genetic differentiation observed at both fine and broad scales. Thus, we inferred linkages among genetic patterns, landscape patterns and ecological processes across spatial scales in M. knabi. Our results reinforce the value of exploring such links simultaneously across multiple spatial scales and landscapes when investigating genetic diversity within a species. © 2011 Blackwell Publishing Ltd.

Spatial Attention and Audiovisual Interactions in Apparent Motion

ERIC Educational Resources Information Center

Sanabria, Daniel; Soto-Faraco, Salvador; Spence, Charles

2007-01-01

In this study, the authors combined the cross-modal dynamic capture task (involving the horizontal apparent movement of visual and auditory stimuli) with spatial cuing in the vertical dimension to investigate the role of spatial attention in cross-modal interactions during motion perception. Spatial attention was manipulated endogenously, either…

Disentangling how landscape spatial and temporal heterogeneity affects Savanna birds.

PubMed

Price, Bronwyn; McAlpine, Clive A; Kutt, Alex S; Ward, Doug; Phinn, Stuart R; Ludwig, John A

2013-01-01

In highly seasonal tropical environments, temporal changes in habitat and resources are a significant determinant of the spatial distribution of species. This study disentangles the effects of spatial and mid to long-term temporal heterogeneity in habitat on the diversity and abundance of savanna birds by testing four competing conceptual models of varying complexity. Focussing on sites in northeast Australia over a 20 year time period, we used ground cover and foliage projected cover surfaces derived from a time series of Landsat Thematic Mapper imagery, rainfall data and site-level vegetation surveys to derive measures of habitat structure at local (1-100 ha) and landscape (100-1000s ha) scales. We used generalised linear models and an information theoretic approach to test the independent effects of spatial and temporal influences on savanna bird diversity and the abundance of eight species with different life-history behaviours. Of four competing models defining influences on assemblages of savanna birds, the most parsimonious included temporal and spatial variability in vegetation cover and site-scale vegetation structure, suggesting savanna bird species respond to spatial and temporal habitat heterogeneity at both the broader landscape scale and at the fine-scale. The relative weight, strength and direction of the explanatory variables changed with each of the eight species, reflecting their different ecology and behavioural traits. This study demonstrates that variations in the spatial pattern of savanna vegetation over periods of 10 to 20 years at the local and landscape scale strongly affect bird diversity and abundance. Thus, it is essential to monitor and manage both spatial and temporal variability in avian habitat to achieve long-term biodiversity outcomes.

Disentangling How Landscape Spatial and Temporal Heterogeneity Affects Savanna Birds

PubMed Central

Price, Bronwyn; McAlpine, Clive A.; Kutt, Alex S.; Ward, Doug; Phinn, Stuart R.; Ludwig, John A.

2013-01-01

In highly seasonal tropical environments, temporal changes in habitat and resources are a significant determinant of the spatial distribution of species. This study disentangles the effects of spatial and mid to long-term temporal heterogeneity in habitat on the diversity and abundance of savanna birds by testing four competing conceptual models of varying complexity. Focussing on sites in northeast Australia over a 20 year time period, we used ground cover and foliage projected cover surfaces derived from a time series of Landsat Thematic Mapper imagery, rainfall data and site-level vegetation surveys to derive measures of habitat structure at local (1–100 ha) and landscape (100–1000s ha) scales. We used generalised linear models and an information theoretic approach to test the independent effects of spatial and temporal influences on savanna bird diversity and the abundance of eight species with different life-history behaviours. Of four competing models defining influences on assemblages of savanna birds, the most parsimonious included temporal and spatial variability in vegetation cover and site-scale vegetation structure, suggesting savanna bird species respond to spatial and temporal habitat heterogeneity at both the broader landscape scale and at the fine-scale. The relative weight, strength and direction of the explanatory variables changed with each of the eight species, reflecting their different ecology and behavioural traits. This study demonstrates that variations in the spatial pattern of savanna vegetation over periods of 10 to 20 years at the local and landscape scale strongly affect bird diversity and abundance. Thus, it is essential to monitor and manage both spatial and temporal variability in avian habitat to achieve long-term biodiversity outcomes. PMID:24066138

On the preservation of cooperation in two-strategy games with nonlocal interactions.

PubMed

Aydogmus, Ozgur; Zhou, Wen; Kang, Yun

2017-03-01

Nonlocal interactions such as spatial interaction are ubiquitous in nature and may alter the equilibrium in evolutionary dynamics. Models including nonlocal spatial interactions can provide a further understanding on the preservation and emergence of cooperation in evolutionary dynamics. In this paper, we consider a variety of two-strategy evolutionary spatial games with nonlocal interactions based on an integro-differential replicator equation. By defining the invasion speed and minimal traveling wave speed for the derived model, we study the effects of the payoffs, the selection pressure and the spatial parameter on the preservation of cooperation. One of our most interesting findings is that, for the Prisoners Dilemma games in which the defection is the only evolutionary stable strategy for unstructured populations, analyses on its asymptotic speed of propagation suggest that, in contrast with spatially homogeneous games, the cooperators can invade the habitat under proper conditions. Other two-strategy evolutionary spatial games are also explored. Both our theoretical and numerical studies show that the nonlocal spatial interaction favors diversity in strategies in a population and is able to preserve cooperation in a competing environment. A real data application in a virus mutation study echoes our theoretical observations. In addition, we compare the results of our model to the partial differential equation approach to demonstrate the importance of including non-local interaction component in evolutionary game models. Copyright © 2016 Elsevier Inc. All rights reserved.

Developmental Path between Language and Autistic-Like Impairments: A Twin Study

ERIC Educational Resources Information Center

Dworzynski, Katharina; Ronald, Angelica; Hayiou-Thomas, Marianna E.; McEwan, Fiona; Happe, Francesca; Bolton, Patrick; Plomin, Robert

2008-01-01

Autism spectrum disorders (ASDs) are diagnosed when individuals show impairments in three behavioural domains: communication, social interactions, and repetitive, restrictive behaviours and interests (RRBIs). Recent data suggest that these three sets of behaviours are genetically heterogeneous. Early language delay is strongly associated with ASD,…

Does the environmental background (intensive v. outdoor systems) influence the behaviour of piglets at weaning?

PubMed

Lau, Y Y W; Pluske, J R; Fleming, P A

2015-08-01

Under intensive pig husbandry, outdoor systems offer a more complex physical and social environment compared with indoor systems (farrowing sheds). As the rearing environment affects behavioural development, it can, therefore, influence behavioural responses of pigs to stressful environments in later stages of production. We tested how the rearing environment influenced behavioural responses to a novel arena test in piglets on the day that they were weaned and mixed into large groups. We recorded video footage and compared the behavioural responses of 30 outdoor-raised and 30 farrowing shed-raised piglets tested in an experimental arena and sequentially exposed to four challenges (each for 5 min) on the day of weaning. Quantitative and qualitative behavioural measures were recorded using time budgets and scoring demeanour or 'qualitative behavioural expression' (using Qualitative Behavioural Assessment (QBA)). When held in isolation (challenge 1), both groups were scored as more 'scared/worried', while outdoor-raised piglets spent more time eating and jumping against the arena walls. Both groups interacted with a plastic ball (challenge 2: exposure to a novel object) during which they were scored as more 'playful/curious' than other challenges. When a food bowl was introduced (challenge 3), farrowing shed-raised piglets were more interested in playing with the food bowl itself, whereas outdoor-raised piglets spent more time eating the feed. Finally, there were no significant differences in social behaviour (challenge 4: introduction of another piglet) between the two groups in terms of the latency to contact each other, amount of time recorded engaged in aggressive/non-aggressive social interactions or QBA scores. Although piglets spent 30% of their time interacting with the other piglet, and half of this time (47%) was engaged in negative interactions (pushing, biting), the levels of aggression were not different between the two groups. Overall, outdoor-raised piglets ate more and were scored as more 'calm/passive', whereas farrowing shed-raised piglets spent more time investigating their environment and were scored as more 'playful/inquisitive'. In conclusion, we did not find differences in behaviour between outdoor-raised and farrowing shed-raised piglets that would highlight welfare issues. The differences found in this study may reflect conflicting affective states, with responses to confinement, neophobia and motivation for exploration evident.

Virtual in Real. Interactive Solutions for Learning and Communication in the National Archaeological Museum of Marche

NASA Astrophysics Data System (ADS)

Clini, P.; Nespeca, R.; Ruggeri, L.

2017-05-01

Today the ICTs are favourable additions to museum exhibitions. This work aims to realize an innovative system of digital exploitation of artefacts in the National Archaeological Museum of Marche (MANaM), in order to create a shared museum that will improve the knowledge of cultural contents through the paradigm "learning by interacting" and "edutainment". The main novelty is the implementation of stand-alone multimedia installations for digital artefacts that combine real and virtual scenarios in order to enrich the experience, the knowledge and the multi-sensory perception. A Digital Library (DL) is created using Close Range Photogrammetry (CRP) techniques applied to 21 archaeological artefacts belonging to different categories. Enriched with other data (texts, images, multimedia), all 3D models flow into the cloud data server from which are recalled in the individual exhibitions. In particular, we have chosen three types of technological solutions: VISUAL, TACTILE, SPATIAL. All the solutions take into account the possibility of group interaction, allowing the participation of the interaction to an appropriate number of users. Sharing the experience enables greater involvement, generating communicative effectiveness much higher than it would get from a lonely visit. From the "Museum Visitors Behaviour Analysis" we obtain a survey about users' needs and efficiency of the interactive solutions. The main result of this work is the educational impact in terms of increase in visitors, specially students, learning increase of historical and cultural content, greater user involvement during the visit to the museum.

MapMySmoke: feasibility of a new quit cigarette smoking mobile phone application using integrated geo-positioning technology, and motivational messaging within a primary care setting.

PubMed

Schick, Robert S; Kelsey, Thomas W; Marston, John; Samson, Kay; Humphris, Gerald W

2018-01-01

Approximately 11,000 people die in Scotland each year as a result of smoking-related causes. Quitting smoking is relatively easy; maintaining a quit attempt is a very difficult task with success rates for unaided quit attempts stubbornly remaining in the single digits. Pharmaceutical treatment can improve these rates by lowering the overall reward factor of nicotine. However, these and related nicotine replacement therapies do not operate on, or address, the spatial and contextual aspects of smoking behaviour. With the ubiquity of smartphones that can log spatial, quantitative and qualitative data related to smoking behaviour, there exists a person-centred clinical opportunity to support smokers attempting to quit by first understanding their smoking behaviour and subsequently sending them dynamic messages to encourage health behaviour change within a situational context. We have built a smartphone app-MapMySmoke-that works on Android and iOS platforms. The deployment of this app within a clinical National Health Service (NHS) setting has two distinct phases: (1) a 2-week logging phase where pre-quit patients log all of their smoking and craving events; and (2) a post-quit phase where users receive dynamic support messages and can continue to log craving events, and should they occur, relapse events. Following the initial logging phase, patients consult with their general practitioner (GP) or healthcare provider to review their smoking patterns and to outline a precise, individualised quit attempt plan. Our feasibility study consists of assessment of an initial app version during and after use by eight patients recruited from an NHS Fife GP practice. In addition to evaluation of the app as a potential smoking cessation aid, we have assessed the user experience, technological requirements and security of the data flow. In an initial feasibility study, we have deployed the app for a small number of patients within one GP practice in NHS Fife. We recruited eight patients within one surgery, four of whom actively logged information about their smoking behaviour. Initial feedback was very positive, and users indicated a willingness to log their craving and smoking events. In addition, two out of three patients who completed follow-up interviews noted that the app helped them reduce the number of cigarettes they smoked per day, while the third indicated that it had helped them quit. The study highlighted the use of pushed notifications as a potential technology for maintaining quit attempts, and the security of collection of data was audited. These initial results influenced the design of a planned second larger study, comprised of 100 patients, the primary objectives of which are to use statistical modelling to identify times and places of probable switches into smoking states, and to target these times with dynamic health behaviour messaging. While the health benefits of quitting smoking are unequivocal, such behaviour change is very difficult to achieve. Many factors are likely to contribute to maintaining smoking behaviour, yet the precise role of cues derived from the spatial environment remains unclear. The rise of smartphones, therefore, allows clinicians the opportunity to better understand the spatial aspects of smoking behaviour and affords them the opportunity to push targeted individualised health support messages at vulnerable times and places. ClinicalTrial.gov, NCT02932917.