Sample records for modeling animal movement

  1. Stochastic modelling of animal movement.

    PubMed

    Smouse, Peter E; Focardi, Stefano; Moorcroft, Paul R; Kie, John G; Forester, James D; Morales, Juan M

    2010-07-27

    Modern animal movement modelling derives from two traditions. Lagrangian models, based on random walk behaviour, are useful for multi-step trajectories of single animals. Continuous Eulerian models describe expected behaviour, averaged over stochastic realizations, and are usefully applied to ensembles of individuals. We illustrate three modern research arenas. (i) Models of home-range formation describe the process of an animal 'settling down', accomplished by including one or more focal points that attract the animal's movements. (ii) Memory-based models are used to predict how accumulated experience translates into biased movement choices, employing reinforced random walk behaviour, with previous visitation increasing or decreasing the probability of repetition. (iii) Lévy movement involves a step-length distribution that is over-dispersed, relative to standard probability distributions, and adaptive in exploring new environments or searching for rare targets. Each of these modelling arenas implies more detail in the movement pattern than general models of movement can accommodate, but realistic empiric evaluation of their predictions requires dense locational data, both in time and space, only available with modern GPS telemetry.

  2. Hierarchical animal movement models for population-level inference

    USGS Publications Warehouse

    Hooten, Mevin B.; Buderman, Frances E.; Brost, Brian M.; Hanks, Ephraim M.; Ivans, Jacob S.

    2016-01-01

    New methods for modeling animal movement based on telemetry data are developed regularly. With advances in telemetry capabilities, animal movement models are becoming increasingly sophisticated. Despite a need for population-level inference, animal movement models are still predominantly developed for individual-level inference. Most efforts to upscale the inference to the population level are either post hoc or complicated enough that only the developer can implement the model. Hierarchical Bayesian models provide an ideal platform for the development of population-level animal movement models but can be challenging to fit due to computational limitations or extensive tuning required. We propose a two-stage procedure for fitting hierarchical animal movement models to telemetry data. The two-stage approach is statistically rigorous and allows one to fit individual-level movement models separately, then resample them using a secondary MCMC algorithm. The primary advantages of the two-stage approach are that the first stage is easily parallelizable and the second stage is completely unsupervised, allowing for an automated fitting procedure in many cases. We demonstrate the two-stage procedure with two applications of animal movement models. The first application involves a spatial point process approach to modeling telemetry data, and the second involves a more complicated continuous-time discrete-space animal movement model. We fit these models to simulated data and real telemetry data arising from a population of monitored Canada lynx in Colorado, USA.

  3. Imputation approaches for animal movement modeling

    USGS Publications Warehouse

    Scharf, Henry; Hooten, Mevin B.; Johnson, Devin S.

    2017-01-01

    The analysis of telemetry data is common in animal ecological studies. While the collection of telemetry data for individual animals has improved dramatically, the methods to properly account for inherent uncertainties (e.g., measurement error, dependence, barriers to movement) have lagged behind. Still, many new statistical approaches have been developed to infer unknown quantities affecting animal movement or predict movement based on telemetry data. Hierarchical statistical models are useful to account for some of the aforementioned uncertainties, as well as provide population-level inference, but they often come with an increased computational burden. For certain types of statistical models, it is straightforward to provide inference if the latent true animal trajectory is known, but challenging otherwise. In these cases, approaches related to multiple imputation have been employed to account for the uncertainty associated with our knowledge of the latent trajectory. Despite the increasing use of imputation approaches for modeling animal movement, the general sensitivity and accuracy of these methods have not been explored in detail. We provide an introduction to animal movement modeling and describe how imputation approaches may be helpful for certain types of models. We also assess the performance of imputation approaches in two simulation studies. Our simulation studies suggests that inference for model parameters directly related to the location of an individual may be more accurate than inference for parameters associated with higher-order processes such as velocity or acceleration. Finally, we apply these methods to analyze a telemetry data set involving northern fur seals (Callorhinus ursinus) in the Bering Sea. Supplementary materials accompanying this paper appear online.

  4. Animal movement: Statistical models for telemetry data

    USGS Publications Warehouse

    Hooten, Mevin B.; Johnson, Devin S.; McClintock, Brett T.; Morales, Juan M.

    2017-01-01

    The study of animal movement has always been a key element in ecological science, because it is inherently linked to critical processes that scale from individuals to populations and communities to ecosystems. Rapid improvements in biotelemetry data collection and processing technology have given rise to a variety of statistical methods for characterizing animal movement. The book serves as a comprehensive reference for the types of statistical models used to study individual-based animal movement

  5. Reflected stochastic differential equation models for constrained animal movement

    USGS Publications Warehouse

    Hanks, Ephraim M.; Johnson, Devin S.; Hooten, Mevin B.

    2017-01-01

    Movement for many animal species is constrained in space by barriers such as rivers, shorelines, or impassable cliffs. We develop an approach for modeling animal movement constrained in space by considering a class of constrained stochastic processes, reflected stochastic differential equations. Our approach generalizes existing methods for modeling unconstrained animal movement. We present methods for simulation and inference based on augmenting the constrained movement path with a latent unconstrained path and illustrate this augmentation with a simulation example and an analysis of telemetry data from a Steller sea lion (Eumatopias jubatus) in southeast Alaska.

  6. Continuous-time discrete-space models for animal movement

    USGS Publications Warehouse

    Hanks, Ephraim M.; Hooten, Mevin B.; Alldredge, Mat W.

    2015-01-01

    The processes influencing animal movement and resource selection are complex and varied. Past efforts to model behavioral changes over time used Bayesian statistical models with variable parameter space, such as reversible-jump Markov chain Monte Carlo approaches, which are computationally demanding and inaccessible to many practitioners. We present a continuous-time discrete-space (CTDS) model of animal movement that can be fit using standard generalized linear modeling (GLM) methods. This CTDS approach allows for the joint modeling of location-based as well as directional drivers of movement. Changing behavior over time is modeled using a varying-coefficient framework which maintains the computational simplicity of a GLM approach, and variable selection is accomplished using a group lasso penalty. We apply our approach to a study of two mountain lions (Puma concolor) in Colorado, USA.

  7. A dynamic Brownian bridge movement model to estimate utilization distributions for heterogeneous animal movement.

    PubMed

    Kranstauber, Bart; Kays, Roland; Lapoint, Scott D; Wikelski, Martin; Safi, Kamran

    2012-07-01

    1. The recently developed Brownian bridge movement model (BBMM) has advantages over traditional methods because it quantifies the utilization distribution of an animal based on its movement path rather than individual points and accounts for temporal autocorrelation and high data volumes. However, the BBMM assumes unrealistic homogeneous movement behaviour across all data. 2. Accurate quantification of the utilization distribution is important for identifying the way animals use the landscape. 3. We improve the BBMM by allowing for changes in behaviour, using likelihood statistics to determine change points along the animal's movement path. 4. This novel extension, outperforms the current BBMM as indicated by simulations and examples of a territorial mammal and a migratory bird. The unique ability of our model to work with tracks that are not sampled regularly is especially important for GPS tags that have frequent failed fixes or dynamic sampling schedules. Moreover, our model extension provides a useful one-dimensional measure of behavioural change along animal tracks. 5. This new method provides a more accurate utilization distribution that better describes the space use of realistic, behaviourally heterogeneous tracks. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

  8. Mapping behavioral landscapes for animal movement: a finite mixture modeling approach

    USGS Publications Warehouse

    Tracey, Jeff A.; Zhu, Jun; Boydston, Erin E.; Lyren, Lisa M.; Fisher, Robert N.; Crooks, Kevin R.

    2013-01-01

    Because of its role in many ecological processes, movement of animals in response to landscape features is an important subject in ecology and conservation biology. In this paper, we develop models of animal movement in relation to objects or fields in a landscape. We take a finite mixture modeling approach in which the component densities are conceptually related to different choices for movement in response to a landscape feature, and the mixing proportions are related to the probability of selecting each response as a function of one or more covariates. We combine particle swarm optimization and an Expectation-Maximization (EM) algorithm to obtain maximum likelihood estimates of the model parameters. We use this approach to analyze data for movement of three bobcats in relation to urban areas in southern California, USA. A behavioral interpretation of the models revealed similarities and differences in bobcat movement response to urbanization. All three bobcats avoided urbanization by moving either parallel to urban boundaries or toward less urban areas as the proportion of urban land cover in the surrounding area increased. However, one bobcat, a male with a dispersal-like large-scale movement pattern, avoided urbanization at lower densities and responded strictly by moving parallel to the urban edge. The other two bobcats, which were both residents and occupied similar geographic areas, avoided urban areas using a combination of movements parallel to the urban edge and movement toward areas of less urbanization. However, the resident female appeared to exhibit greater repulsion at lower levels of urbanization than the resident male, consistent with empirical observations of bobcats in southern California. Using the parameterized finite mixture models, we mapped behavioral states to geographic space, creating a representation of a behavioral landscape. This approach can provide guidance for conservation planning based on analysis of animal movement data using

  9. Analyzing animal movements using Brownian bridges.

    PubMed

    Horne, Jon S; Garton, Edward O; Krone, Stephen M; Lewis, Jesse S

    2007-09-01

    By studying animal movements, researchers can gain insight into many of the ecological characteristics and processes important for understanding population-level dynamics. We developed a Brownian bridge movement model (BBMM) for estimating the expected movement path of an animal, using discrete location data obtained at relatively short time intervals. The BBMM is based on the properties of a conditional random walk between successive pairs of locations, dependent on the time between locations, the distance between locations, and the Brownian motion variance that is related to the animal's mobility. We describe two critical developments that enable widespread use of the BBMM, including a derivation of the model when location data are measured with error and a maximum likelihood approach for estimating the Brownian motion variance. After the BBMM is fitted to location data, an estimate of the animal's probability of occurrence can be generated for an area during the time of observation. To illustrate potential applications, we provide three examples: estimating animal home ranges, estimating animal migration routes, and evaluating the influence of fine-scale resource selection on animal movement patterns.

  10. Advancing research on animal-transported subsidies by integrating animal movement and ecosystem modelling.

    PubMed

    Earl, Julia E; Zollner, Patrick A

    2017-09-01

    Connections between ecosystems via animals (active subsidies) support ecosystem services and contribute to numerous ecological effects. Thus, the ability to predict the spatial distribution of active subsidies would be useful for ecology and conservation. Previous work modelling active subsidies focused on implicit space or static distributions, which treat passive and active subsidies similarly. Active subsidies are fundamentally different from passive subsidies, because animals can respond to the process of subsidy deposition and ecosystem changes caused by subsidy deposition. We propose addressing this disparity by integrating animal movement and ecosystem ecology to advance active subsidy investigations, make more accurate predictions of subsidy spatial distributions, and enable a mechanistic understanding of subsidy spatial distributions. We review selected quantitative techniques that could be used to accomplish integration and lead to novel insights. The ultimate objective for these types of studies is predictions of subsidy spatial distributions from characteristics of the subsidy and the movement strategy employed by animals that transport subsidies. These advances will be critical in informing the management of ecosystem services, species conservation and ecosystem degradation related to active subsidies. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  11. Basis function models for animal movement

    USGS Publications Warehouse

    Hooten, Mevin B.; Johnson, Devin S.

    2017-01-01

    Advances in satellite-based data collection techniques have served as a catalyst for new statistical methodology to analyze these data. In wildlife ecological studies, satellite-based data and methodology have provided a wealth of information about animal space use and the investigation of individual-based animal–environment relationships. With the technology for data collection improving dramatically over time, we are left with massive archives of historical animal telemetry data of varying quality. While many contemporary statistical approaches for inferring movement behavior are specified in discrete time, we develop a flexible continuous-time stochastic integral equation framework that is amenable to reduced-rank second-order covariance parameterizations. We demonstrate how the associated first-order basis functions can be constructed to mimic behavioral characteristics in realistic trajectory processes using telemetry data from mule deer and mountain lion individuals in western North America. Our approach is parallelizable and provides inference for heterogenous trajectories using nonstationary spatial modeling techniques that are feasible for large telemetry datasets. Supplementary materials for this article are available online.

  12. 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.

  13. Maximum-entropy description of animal movement.

    PubMed

    Fleming, Chris H; Subaşı, Yiğit; Calabrese, Justin M

    2015-03-01

    We introduce a class of maximum-entropy states that naturally includes within it all of the major continuous-time stochastic processes that have been applied to animal movement, including Brownian motion, Ornstein-Uhlenbeck motion, integrated Ornstein-Uhlenbeck motion, a recently discovered hybrid of the previous models, and a new model that describes central-place foraging. We are also able to predict a further hierarchy of new models that will emerge as data quality improves to better resolve the underlying continuity of animal movement. Finally, we also show that Langevin equations must obey a fluctuation-dissipation theorem to generate processes that fall from this class of maximum-entropy distributions when the constraints are purely kinematic.

  14. What is the animal doing? Tools for exploring behavioural structure in animal movements.

    PubMed

    Gurarie, Eliezer; Bracis, Chloe; Delgado, Maria; Meckley, Trevor D; Kojola, Ilpo; Wagner, C Michael

    2016-01-01

    Movement data provide a window - often our only window - into the cognitive, social and biological processes that underlie the behavioural ecology of animals in the wild. Robust methods for identifying and interpreting distinct modes of movement behaviour are of great importance, but complicated by the fact that movement data are complex, multivariate and dependent. Many different approaches to exploratory analysis of movement have been developed to answer similar questions, and practitioners are often at a loss for how to choose an appropriate tool for a specific question. We apply and compare four methodological approaches: first passage time (FPT), Bayesian partitioning of Markov models (BPMM), behavioural change point analysis (BCPA) and a fitted multistate random walk (MRW) to three simulated tracks and two animal trajectories - a sea lamprey (Petromyzon marinus) tracked for 12 h and a wolf (Canis lupus) tracked for 1 year. The simulations - in which, respectively, velocity, tortuosity and spatial bias change - highlight the sensitivity of all methods to model misspecification. Methods that do not account for autocorrelation in the movement variables lead to spurious change points, while methods that do not account for spatial bias completely miss changes in orientation. When applied to the animal data, the methods broadly agree on the structure of the movement behaviours. Important discrepancies, however, reflect differences in the assumptions and nature of the outputs. Important trade-offs are between the strength of the a priori assumptions (low in BCPA, high in MRW), complexity of output (high in the BCPA, low in the BPMM and MRW) and explanatory potential (highest in the MRW). The animal track analysis suggests some general principles for the exploratory analysis of movement data, including ways to exploit the strengths of the various methods. We argue for close and detailed exploratory analysis of movement before fitting complex movement models. © 2015

  15. On modeling animal movements using Brownian motion with measurement error.

    PubMed

    Pozdnyakov, Vladimir; Meyer, Thomas; Wang, Yu-Bo; Yan, Jun

    2014-02-01

    Modeling animal movements with Brownian motion (or more generally by a Gaussian process) has a long tradition in ecological studies. The recent Brownian bridge movement model (BBMM), which incorporates measurement errors, has been quickly adopted by ecologists because of its simplicity and tractability. We discuss some nontrivial properties of the discrete-time stochastic process that results from observing a Brownian motion with added normal noise at discrete times. In particular, we demonstrate that the observed sequence of random variables is not Markov. Consequently the expected occupation time between two successively observed locations does not depend on just those two observations; the whole path must be taken into account. Nonetheless, the exact likelihood function of the observed time series remains tractable; it requires only sparse matrix computations. The likelihood-based estimation procedure is described in detail and compared to the BBMM estimation.

  16. 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.

  17. Partial differential equation techniques for analysing animal movement: A comparison of different methods.

    PubMed

    Wang, Yi-Shan; Potts, Jonathan R

    2017-03-07

    Recent advances in animal tracking have allowed us to uncover the drivers of movement in unprecedented detail. This has enabled modellers to construct ever more realistic models of animal movement, which aid in uncovering detailed patterns of space use in animal populations. Partial differential equations (PDEs) provide a popular tool for mathematically analysing such models. However, their construction often relies on simplifying assumptions which may greatly affect the model outcomes. Here, we analyse the effect of various PDE approximations on the analysis of some simple movement models, including a biased random walk, central-place foraging processes and movement in heterogeneous landscapes. Perhaps the most commonly-used PDE method dates back to a seminal paper of Patlak from 1953. However, our results show that this can be a very poor approximation in even quite simple models. On the other hand, more recent methods, based on transport equation formalisms, can provide more accurate results, as long as the kernel describing the animal's movement is sufficiently smooth. When the movement kernel is not smooth, we show that both the older and newer methods can lead to quantitatively misleading results. Our detailed analysis will aid future researchers in the appropriate choice of PDE approximation for analysing models of animal movement. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. When to be discrete: the importance of time formulation in understanding animal movement.

    PubMed

    McClintock, Brett T; Johnson, Devin S; Hooten, Mevin B; Ver Hoef, Jay M; Morales, Juan M

    2014-01-01

    Animal movement is essential to our understanding of population dynamics, animal behavior, and the impacts of global change. Coupled with high-resolution biotelemetry data, exciting new inferences about animal movement have been facilitated by various specifications of contemporary models. These approaches differ, but most share common themes. One key distinction is whether the underlying movement process is conceptualized in discrete or continuous time. This is perhaps the greatest source of confusion among practitioners, both in terms of implementation and biological interpretation. In general, animal movement occurs in continuous time but we observe it at fixed discrete-time intervals. Thus, continuous time is conceptually and theoretically appealing, but in practice it is perhaps more intuitive to interpret movement in discrete intervals. With an emphasis on state-space models, we explore the differences and similarities between continuous and discrete versions of mechanistic movement models, establish some common terminology, and indicate under which circumstances one form might be preferred over another. Counter to the overly simplistic view that discrete- and continuous-time conceptualizations are merely different means to the same end, we present novel mathematical results revealing hitherto unappreciated consequences of model formulation on inferences about animal movement. Notably, the speed and direction of movement are intrinsically linked in current continuous-time random walk formulations, and this can have important implications when interpreting animal behavior. We illustrate these concepts in the context of state-space models with multiple movement behavior states using northern fur seal (Callorhinus ursinus) biotelemetry data.

  19. When to be discrete: The importance of time formulation in understanding animal movement

    USGS Publications Warehouse

    McClintock, Brett T.; Johnson, Devin S.; Hooten, Mevin B.; Ver Hoef, Jay M.; Morales, Juan M.

    2014-01-01

    Animal movement is essential to our understanding of population dynamics, animal behavior, and the impacts of global change. Coupled with high-resolution biotelemetry data, exciting new inferences about animal movement have been facilitated by various specifications of contemporary models. These approaches differ, but most share common themes. One key distinction is whether the underlying movement process is conceptualized in discrete or continuous time. This is perhaps the greatest source of confusion among practitioners, both in terms of implementation and biological interpretation. In general, animal movement occurs in continuous time but we observe it at fixed discrete-time intervals. Thus, continuous time is conceptually and theoretically appealing, but in practice it is perhaps more intuitive to interpret movement in discrete intervals. With an emphasis on state-space models, we explore the differences and similarities between continuous and discrete versions of mechanistic movement models, establish some common terminology, and indicate under which circumstances one form might be preferred over another. Counter to the overly simplistic view that discrete- and continuous-time conceptualizations are merely different means to the same end, we present novel mathematical results revealing hitherto unappreciated consequences of model formulation on inferences about animal movement. Notably, the speed and direction of movement are intrinsically linked in current continuous-time random walk formulations, and this can have important implications when interpreting animal behavior. We illustrate these concepts in the context of state-space models with multiple movement behavior states using northern fur seal (Callorhinus ursinus) biotelemetry data.

  20. Uniting Statistical and Individual-Based Approaches for Animal Movement Modelling

    PubMed Central

    Latombe, Guillaume; Parrott, Lael; Basille, Mathieu; Fortin, Daniel

    2014-01-01

    The dynamic nature of their internal states and the environment directly shape animals' spatial behaviours and give rise to emergent properties at broader scales in natural systems. However, integrating these dynamic features into habitat selection studies remains challenging, due to practically impossible field work to access internal states and the inability of current statistical models to produce dynamic outputs. To address these issues, we developed a robust method, which combines statistical and individual-based modelling. Using a statistical technique for forward modelling of the IBM has the advantage of being faster for parameterization than a pure inverse modelling technique and allows for robust selection of parameters. Using GPS locations from caribou monitored in Québec, caribou movements were modelled based on generative mechanisms accounting for dynamic variables at a low level of emergence. These variables were accessed by replicating real individuals' movements in parallel sub-models, and movement parameters were then empirically parameterized using Step Selection Functions. The final IBM model was validated using both k-fold cross-validation and emergent patterns validation and was tested for two different scenarios, with varying hardwood encroachment. Our results highlighted a functional response in habitat selection, which suggests that our method was able to capture the complexity of the natural system, and adequately provided projections on future possible states of the system in response to different management plans. This is especially relevant for testing the long-term impact of scenarios corresponding to environmental configurations that have yet to be observed in real systems. PMID:24979047

  1. Uniting statistical and individual-based approaches for animal movement modelling.

    PubMed

    Latombe, Guillaume; Parrott, Lael; Basille, Mathieu; Fortin, Daniel

    2014-01-01

    The dynamic nature of their internal states and the environment directly shape animals' spatial behaviours and give rise to emergent properties at broader scales in natural systems. However, integrating these dynamic features into habitat selection studies remains challenging, due to practically impossible field work to access internal states and the inability of current statistical models to produce dynamic outputs. To address these issues, we developed a robust method, which combines statistical and individual-based modelling. Using a statistical technique for forward modelling of the IBM has the advantage of being faster for parameterization than a pure inverse modelling technique and allows for robust selection of parameters. Using GPS locations from caribou monitored in Québec, caribou movements were modelled based on generative mechanisms accounting for dynamic variables at a low level of emergence. These variables were accessed by replicating real individuals' movements in parallel sub-models, and movement parameters were then empirically parameterized using Step Selection Functions. The final IBM model was validated using both k-fold cross-validation and emergent patterns validation and was tested for two different scenarios, with varying hardwood encroachment. Our results highlighted a functional response in habitat selection, which suggests that our method was able to capture the complexity of the natural system, and adequately provided projections on future possible states of the system in response to different management plans. This is especially relevant for testing the long-term impact of scenarios corresponding to environmental configurations that have yet to be observed in real systems.

  2. Using GIS to analyze animal movements in the marine environment

    USGS Publications Warehouse

    Hooge, Philip N.; Eichenlaub, William M.; Solomon, Elizabeth K.; Kruse, Gordon H.; Bez, Nicolas; Booth, Anthony; Dorn, Martin W.; Hills, Susan; Lipcius, Romuald N.; Pelletier, Dominique; Roy, Claude; Smith, Stephen J.; Witherell, David B.

    2001-01-01

    Advanced methods for analyzing animal movements have been little used in the aquatic research environment compared to the terrestrial. In addition, despite obvious advantages of integrating geographic information systems (GIS) with spatial studies of animal movement behavior, movement analysis tools have not been integrated into GIS for either aquatic or terrestrial environments. We therefore developed software that integrates one of the most commonly used GIS programs (ArcView®) with a large collection of animal movement analysis tools. This application, the Animal Movement Analyst Extension (AMAE), can be loaded as an extension to ArcView® under multiple operating system platforms (PC, Unix, and Mac OS). It contains more than 50 functions, including parametric and nonparametric home range analyses, random walk models, habitat analyses, point and circular statistics, tests of complete spatial randomness, tests for autocorrelation and sample size, point and line manipulation tools, and animation tools. This paper describes the use of these functions in analyzing animal location data; some limited examples are drawn from a sonic-tracking study of Pacific halibut (Hippoglossus stenolepis) in Glacier Bay, Alaska. The extension is available on the Internet at www.absc.usgs.gov/glba/gistools/index.htm.

  3. The importance of individual variation in the dynamics of animal collective movements.

    PubMed

    Del Mar Delgado, Maria; Miranda, Maria; Alvarez, Silvia J; Gurarie, Eliezer; Fagan, William F; Penteriani, Vincenzo; di Virgilio, Agustina; Morales, Juan Manuel

    2018-05-19

    Animal collective movements are a key example of a system that links two clearly defined levels of organization: the individual and the group. Most models investigating collective movements have generated coherent collective behaviours without the inclusion of individual variability. However, new individual-based models, together with emerging empirical information, emphasize that within-group heterogeneity may strongly influence collective movement behaviour. Here we (i) review the empirical evidence for individual variation in animal collective movements, (ii) explore how theoretical investigations have represented individual heterogeneity when modelling collective movements and (iii) present a model to show how within-group heterogeneity influences the collective properties of a group. Our review underscores the need to consider variability at the level of the individual to improve our understanding of how individual decision rules lead to emergent movement patterns, and also to yield better quantitative predictions of collective behaviour.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Author(s).

  4. Memory Effects on Movement Behavior in Animal Foraging.

    PubMed

    Bracis, Chloe; Gurarie, Eliezer; Van Moorter, Bram; Goodwin, R Andrew

    2015-01-01

    An individual's choices are shaped by its experience, a fundamental property of behavior important to understanding complex processes. Learning and memory are observed across many taxa and can drive behaviors, including foraging behavior. To explore the conditions under which memory provides an advantage, we present a continuous-space, continuous-time model of animal movement that incorporates learning and memory. Using simulation models, we evaluate the benefit memory provides across several types of landscapes with variable-quality resources and compare the memory model within a nested hierarchy of simpler models (behavioral switching and random walk). We find that memory almost always leads to improved foraging success, but that this effect is most marked in landscapes containing sparse, contiguous patches of high-value resources that regenerate relatively fast and are located in an otherwise devoid landscape. In these cases, there is a large payoff for finding a resource patch, due to size, value, or locational difficulty. While memory-informed search is difficult to differentiate from other factors using solely movement data, our results suggest that disproportionate spatial use of higher value areas, higher consumption rates, and consumption variability all point to memory influencing the movement direction of animals in certain ecosystems.

  5. Novel technology for measuring animal movement on rangelands

    USDA-ARS?s Scientific Manuscript database

    Previous comparisons of animal responses to grazing management have largely focused on animal weight gains. As a result, we have an incomplete understanding of the effects of grazing management on attributes such as animal movement. Moreover, the influence of animal movement such as the distance tra...

  6. Combining High-Speed Cameras and Stop-Motion Animation Software to Support Students' Modeling of Human Body Movement

    NASA Astrophysics Data System (ADS)

    Lee, Victor R.

    2015-04-01

    Biomechanics, and specifically the biomechanics associated with human movement, is a potentially rich backdrop against which educators can design innovative science teaching and learning activities. Moreover, the use of technologies associated with biomechanics research, such as high-speed cameras that can produce high-quality slow-motion video, can be deployed in such a way to support students' participation in practices of scientific modeling. As participants in classroom design experiment, fifteen fifth-grade students worked with high-speed cameras and stop-motion animation software (SAM Animation) over several days to produce dynamic models of motion and body movement. The designed series of learning activities involved iterative cycles of animation creation and critique and use of various depictive materials. Subsequent analysis of flipbooks of human jumping movements created by the students at the beginning and end of the unit revealed a significant improvement in both the epistemic fidelity of students' representations. Excerpts from classroom observations highlight the role that the teacher plays in supporting students' thoughtful reflection of and attention to slow-motion video. In total, this design and research intervention demonstrates that the combination of technologies, activities, and teacher support can lead to improvements in some of the foundations associated with students' modeling.

  7. Memory Effects on Movement Behavior in Animal Foraging

    PubMed Central

    Bracis, Chloe; Gurarie, Eliezer; Van Moorter, Bram; Goodwin, R. Andrew

    2015-01-01

    An individual’s choices are shaped by its experience, a fundamental property of behavior important to understanding complex processes. Learning and memory are observed across many taxa and can drive behaviors, including foraging behavior. To explore the conditions under which memory provides an advantage, we present a continuous-space, continuous-time model of animal movement that incorporates learning and memory. Using simulation models, we evaluate the benefit memory provides across several types of landscapes with variable-quality resources and compare the memory model within a nested hierarchy of simpler models (behavioral switching and random walk). We find that memory almost always leads to improved foraging success, but that this effect is most marked in landscapes containing sparse, contiguous patches of high-value resources that regenerate relatively fast and are located in an otherwise devoid landscape. In these cases, there is a large payoff for finding a resource patch, due to size, value, or locational difficulty. While memory-informed search is difficult to differentiate from other factors using solely movement data, our results suggest that disproportionate spatial use of higher value areas, higher consumption rates, and consumption variability all point to memory influencing the movement direction of animals in certain ecosystems. PMID:26288228

  8. Estimating abundance of an open population with an N-mixture model using auxiliary data on animal movements.

    PubMed

    Ketz, Alison C; Johnson, Therese L; Monello, Ryan J; Mack, John A; George, Janet L; Kraft, Benjamin R; Wild, Margaret A; Hooten, Mevin B; Hobbs, N Thompson

    2018-04-01

    Accurate assessment of abundance forms a central challenge in population ecology and wildlife management. Many statistical techniques have been developed to estimate population sizes because populations change over time and space and to correct for the bias resulting from animals that are present in a study area but not observed. The mobility of individuals makes it difficult to design sampling procedures that account for movement into and out of areas with fixed jurisdictional boundaries. Aerial surveys are the gold standard used to obtain data of large mobile species in geographic regions with harsh terrain, but these surveys can be prohibitively expensive and dangerous. Estimating abundance with ground-based census methods have practical advantages, but it can be difficult to simultaneously account for temporary emigration and observer error to avoid biased results. Contemporary research in population ecology increasingly relies on telemetry observations of the states and locations of individuals to gain insight on vital rates, animal movements, and population abundance. Analytical models that use observations of movements to improve estimates of abundance have not been developed. Here we build upon existing multi-state mark-recapture methods using a hierarchical N-mixture model with multiple sources of data, including telemetry data on locations of individuals, to improve estimates of population sizes. We used a state-space approach to model animal movements to approximate the number of marked animals present within the study area at any observation period, thereby accounting for a frequently changing number of marked individuals. We illustrate the approach using data on a population of elk (Cervus elaphus nelsoni) in Northern Colorado, USA. We demonstrate substantial improvement compared to existing abundance estimation methods and corroborate our results from the ground based surveys with estimates from aerial surveys during the same seasons. We develop a

  9. Animal movement constraints improve resource selection inference in the presence of telemetry error

    USGS Publications Warehouse

    Brost, Brian M.; Hooten, Mevin B.; Hanks, Ephraim M.; Small, Robert J.

    2016-01-01

    Multiple factors complicate the analysis of animal telemetry location data. Recent advancements address issues such as temporal autocorrelation and telemetry measurement error, but additional challenges remain. Difficulties introduced by complicated error structures or barriers to animal movement can weaken inference. We propose an approach for obtaining resource selection inference from animal location data that accounts for complicated error structures, movement constraints, and temporally autocorrelated observations. We specify a model for telemetry data observed with error conditional on unobserved true locations that reflects prior knowledge about constraints in the animal movement process. The observed telemetry data are modeled using a flexible distribution that accommodates extreme errors and complicated error structures. Although constraints to movement are often viewed as a nuisance, we use constraints to simultaneously estimate and account for telemetry error. We apply the model to simulated data, showing that it outperforms common ad hoc approaches used when confronted with measurement error and movement constraints. We then apply our framework to an Argos satellite telemetry data set on harbor seals (Phoca vitulina) in the Gulf of Alaska, a species that is constrained to move within the marine environment and adjacent coastlines.

  10. Integrating animal movement with habitat suitability for estimating dynamic landscape connectivity

    USGS Publications Warehouse

    van Toor, Mariëlle L.; Kranstauber, Bart; Newman, Scott H.; Prosser, Diann J.; Takekawa, John Y.; Technitis, Georgios; Weibel, Robert; Wikelski, Martin; Safi, Kamran

    2018-01-01

    Context High-resolution animal movement data are becoming increasingly available, yet having a multitude of empirical trajectories alone does not allow us to easily predict animal movement. To answer ecological and evolutionary questions at a population level, quantitative estimates of a species’ potential to link patches or populations are of importance. Objectives We introduce an approach that combines movement-informed simulated trajectories with an environment-informed estimate of the trajectories’ plausibility to derive connectivity. Using the example of bar-headed geese we estimated migratory connectivity at a landscape level throughout the annual cycle in their native range. Methods We used tracking data of bar-headed geese to develop a multi-state movement model and to estimate temporally explicit habitat suitability within the species’ range. We simulated migratory movements between range fragments, and calculated a measure we called route viability. The results are compared to expectations derived from published literature. Results Simulated migrations matched empirical trajectories in key characteristics such as stopover duration. The viability of the simulated trajectories was similar to that of the empirical trajectories. We found that, overall, the migratory connectivity was higher within the breeding than in wintering areas, corroborating previous findings for this species. Conclusions We show how empirical tracking data and environmental information can be fused for meaningful predictions of animal movements throughout the year and even outside the spatial range of the available data. Beyond predicting migratory connectivity, our framework will prove useful for modelling ecological processes facilitated by animal movement, such as seed dispersal or disease ecology.

  11. Mechanistic movement models to understand epidemic spread.

    PubMed

    Fofana, Abdou Moutalab; Hurford, Amy

    2017-05-05

    An overlooked aspect of disease ecology is considering how and why animals come into contact with one and other resulting in disease transmission. Mathematical models of disease spread frequently assume mass-action transmission, justified by stating that susceptible and infectious hosts mix readily, and foregoing any detailed description of host movement. Numerous recent studies have recorded, analysed and modelled animal movement. These movement models describe how animals move with respect to resources, conspecifics and previous movement directions and have been used to understand the conditions for the occurrence and the spread of infectious diseases when hosts perform a type of movement. Here, we summarize the effect of the different types of movement on the threshold conditions for disease spread. We identify gaps in the literature and suggest several promising directions for future research. The mechanistic inclusion of movement in epidemic models may be beneficial for the following two reasons. Firstly, the estimation of the transmission coefficient in an epidemic model is possible because animal movement data can be used to estimate the rate of contacts between conspecifics. Secondly, unsuccessful transmission events, where a susceptible host contacts an infectious host but does not become infected can be quantified. Following an outbreak, this enables disease ecologists to identify 'near misses' and to explore possible alternative epidemic outcomes given shifts in ecological or immunological parameters.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'. © 2017 The Author(s).

  12. Animal movement in the absence of predation: environmental drivers of movement strategies in a partial migration system

    USGS Publications Warehouse

    Bastille-Rousseau, Guillaume; Gibbs, James P.; Yackulic, Charles B.; Frair, Jacqueline L.; Cabrera, Fredy; Rousseau, Louis-Philippe

    2016-01-01

    Animal movement strategies including migration, dispersal, nomadism, and residency are shaped by broad-scale spatial-temporal structuring of the environment, including factors such as the degrees of spatial variation, seasonality and inter-annual predictability. Animal movement strategies, in turn, interact with the characteristics of individuals and the local distribution of resources to determine local patterns of resource selection with complex and poorly understood implications for animal fitness. Here we present a multi-scale investigation of animal movement strategies and resource selection. We consider the degree to which spatial variation, seasonality, and inter-annual predictability in resources drive migration patterns among different taxa and how movement strategies in turn shape local resource selection patterns. We focus on adult Galapagos giant tortoises Chelonoidis spp. as a model system since they display many movement strategies and evolved in the absence of predators of adults. Specifically, our analysis is based on 63 individuals among four taxa tracked on three islands over six years and almost 106 tortoise re-locations. Tortoises displayed a continuum of movement strategies from migration to sedentarism that were linked to the spatio-temporal scale and predictability of resource distributions. Movement strategies shaped patterns of resource selection. Specifically, migratory individuals displayed stronger selection toward areas where resources were more predictable among years than did non-migratory individuals, which indicates a selective advantage for migrants in seasonally structured, more predictable environments. Our analytical framework combines large-scale predictions for movement strategies, based on environmental structuring, with finer-scale analysis of space-use. Integrating different organizational levels of analysis provides a deeper understanding of the eco-evolutionary dynamics at play in the emergence and maintenance of

  13. Can orchards help connect Mediterranean ecosystems? Animal movement data alter conservation priorities

    USGS Publications Warehouse

    Nogeire, Theresa M.; Davis, Frank W.; Crooks, Kevin R.; McRae, Brad H.; Lyren, Lisa M.; Boydston, Erin E.

    2015-01-01

    As natural habitats become fragmented by human activities, animals must increasingly move through human-dominated systems, particularly agricultural landscapes. Mapping areas important for animal movement has therefore become a key part of conservation planning. Models of landscape connectivity are often parameterized using expert opinion and seldom distinguish between the risks and barriers presented by different crop types. Recent research, however, suggests different crop types, such as row crops and orchards, differ in the degree to which they facilitate or impede species movements. Like many mammalian carnivores, bobcats (Lynx rufus) are sensitive to fragmentation and loss of connectivity between habitat patches. We investigated how distinguishing between different agricultural land covers might change conclusions about the relative conservation importance of different land uses in a Mediterranean ecosystem. Bobcats moved relatively quickly in row crops but relatively slowly in orchards, at rates similar to those in natural habitats of woodlands and scrub. We found that parameterizing a connectivity model using empirical data on bobcat movements in agricultural lands and other land covers, instead of parameterizing the model using habitat suitability indices based on expert opinion, altered locations of predicted animal movement routes. These results emphasize that differentiating between types of agriculture can alter conservation planning outcomes.

  14. Spatiotemporal Variation in Distance Dependent Animal Movement Contacts: One Size Doesn’t Fit All

    PubMed Central

    Brommesson, Peter; Wennergren, Uno; Lindström, Tom

    2016-01-01

    The structure of contacts that mediate transmission has a pronounced effect on the outbreak dynamics of infectious disease and simulation models are powerful tools to inform policy decisions. Most simulation models of livestock disease spread rely to some degree on predictions of animal movement between holdings. Typically, movements are more common between nearby farms than between those located far away from each other. Here, we assessed spatiotemporal variation in such distance dependence of animal movement contacts from an epidemiological perspective. We evaluated and compared nine statistical models, applied to Swedish movement data from 2008. The models differed in at what level (if at all), they accounted for regional and/or seasonal heterogeneities in the distance dependence of the contacts. Using a kernel approach to describe how probability of contacts between farms changes with distance, we developed a hierarchical Bayesian framework and estimated parameters by using Markov Chain Monte Carlo techniques. We evaluated models by three different approaches of model selection. First, we used Deviance Information Criterion to evaluate their performance relative to each other. Secondly, we estimated the log predictive posterior distribution, this was also used to evaluate their relative performance. Thirdly, we performed posterior predictive checks by simulating movements with each of the parameterized models and evaluated their ability to recapture relevant summary statistics. Independent of selection criteria, we found that accounting for regional heterogeneity improved model accuracy. We also found that accounting for seasonal heterogeneity was beneficial, in terms of model accuracy, according to two of three methods used for model selection. Our results have important implications for livestock disease spread models where movement is an important risk factor for between farm transmission. We argue that modelers should refrain from using methods to simulate

  15. Modeling animal movements using stochastic differential equations

    Treesearch

    Haiganoush K. Preisler; Alan A. Ager; Bruce K. Johnson; John G. Kie

    2004-01-01

    We describe the use of bivariate stochastic differential equations (SDE) for modeling movements of 216 radiocollared female Rocky Mountain elk at the Starkey Experimental Forest and Range in northeastern Oregon. Spatially and temporally explicit vector fields were estimated using approximating difference equations and nonparametric regression techniques. Estimated...

  16. Coupling movement and landscape ecology for animal conservation in production landscapes.

    PubMed

    Doherty, Tim S; Driscoll, Don A

    2018-01-10

    Habitat conversion in production landscapes is among the greatest threats to biodiversity, not least because it can disrupt animal movement. Using the movement ecology framework, we review animal movement in production landscapes, including areas managed for agriculture and forestry. We consider internal and external drivers of altered animal movement and how this affects navigation and motion capacities and population dynamics. Conventional management approaches in fragmented landscapes focus on promoting connectivity using structural changes in the landscape. However, a movement ecology perspective emphasizes that manipulating the internal motivations or navigation capacity of animals represents untapped opportunities to improve movement and the effectiveness of structural connectivity investments. Integrating movement and landscape ecology opens new opportunities for conservation management in production landscapes. © 2018 The Authors.

  17. Predicting oscillatory dynamics in the movement of territorial animals.

    PubMed

    Giuggioli, L; Potts, J R; Harris, S

    2012-07-07

    Understanding ecological processes relies upon the knowledge of the dynamics of each individual component. In the context of animal population ecology, the way animals move and interact is of fundamental importance in explaining a variety of observed patterns. Here, we present a theoretical investigation on the movement dynamics of interacting scent-marking animals. We study how the movement statistics of territorial animals is responsible for the appearance of damped oscillations in the mean square displacement (MSD) of the animals. This non-monotonicity is shown to depend on one dimensionless parameter, given by the ratio of the correlation distance between successive steps to the size of the territory. As that parameter increases, the time dependence of the animal's MSD displays a transition from monotonic, characteristic of Brownian walks, to non-monotonic, characteristic of highly correlated walks. The results presented here represent a novel way of determining the degree of persistence in animal movement processes within confined regions.

  18. Predicting oscillatory dynamics in the movement of territorial animals

    PubMed Central

    Giuggioli, L.; Potts, J. R.; Harris, S.

    2012-01-01

    Understanding ecological processes relies upon the knowledge of the dynamics of each individual component. In the context of animal population ecology, the way animals move and interact is of fundamental importance in explaining a variety of observed patterns. Here, we present a theoretical investigation on the movement dynamics of interacting scent-marking animals. We study how the movement statistics of territorial animals is responsible for the appearance of damped oscillations in the mean square displacement (MSD) of the animals. This non-monotonicity is shown to depend on one dimensionless parameter, given by the ratio of the correlation distance between successive steps to the size of the territory. As that parameter increases, the time dependence of the animal's MSD displays a transition from monotonic, characteristic of Brownian walks, to non-monotonic, characteristic of highly correlated walks. The results presented here represent a novel way of determining the degree of persistence in animal movement processes within confined regions. PMID:22262814

  19. Role of animal movement and indirect contact among farms in transmission of porcine epidemic diarrhea virus.

    PubMed

    VanderWaal, Kimberly; Perez, Andres; Torremorrell, Montse; Morrison, Robert M; Craft, Meggan

    2018-04-12

    Epidemiological models of the spread of pathogens in livestock populations primarily focus on direct contact between farms based on animal movement data, and in some cases, local spatial spread based on proximity between premises. The roles of other types of indirect contact among farms is rarely accounted for. In addition, data on animal movements is seldom available in the United States. However, the spread of porcine epidemic diarrhea virus (PEDv) in U.S. swine represents one of the best documented emergences of a highly infectious pathogen in the U.S. livestock industry, providing an opportunity to parameterize models of pathogen spread via direct and indirect transmission mechanisms in swine. Using observed data on pig movements during the initial phase of the PEDv epidemic, we developed a network-based and spatially explicit epidemiological model that simulates the spread of PEDv via both indirect and direct movement-related contact in order to answer unresolved questions concerning factors facilitating between-farm transmission. By modifying the likelihood of each transmission mechanism and fitting this model to observed epidemiological dynamics, our results suggest that between-farm transmission was primarily driven by direct mechanisms related to animal movement and indirect mechanisms related to local spatial spread based on geographic proximity. However, other forms of indirect transmission among farms, including contact via contaminated vehicles and feed, were responsible for high consequence transmission events resulting in the introduction of the virus into new geographic areas. This research is among the first reports of farm-level animal movements in the U.S. swine industry and, to our knowledge, represents the first epidemiological model of commercial U.S. swine using actual data on farm-level animal movement. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Error in telemetry studies: Effects of animal movement on triangulation

    USGS Publications Warehouse

    Schmutz, Joel A.; White, Gary C.

    1990-01-01

    We used Monte Carlo simulations to investigate the effects of animal movement on error of estimated animal locations derived from radio-telemetry triangulation of sequentially obtained bearings. Simulated movements of 0-534 m resulted in up to 10-fold increases in average location error but <10% decreases in location precision when observer-to-animal distances were <1,000 m. Location error and precision were minimally affected by censorship of poor locations with Chi-square goodness-of-fit tests. Location error caused by animal movement can only be eliminated by taking simultaneous bearings.

  1. Understanding how animal groups achieve coordinated movement

    PubMed Central

    Herbert-Read, J. E.

    2016-01-01

    ABSTRACT Moving animal groups display remarkable feats of coordination. This coordination is largely achieved when individuals adjust their movement in response to their neighbours' movements and positions. Recent advancements in automated tracking technologies, including computer vision and GPS, now allow researchers to gather large amounts of data on the movements and positions of individuals in groups. Furthermore, analytical techniques from fields such as statistical physics now allow us to identify the precise interaction rules used by animals on the move. These interaction rules differ not only between species, but also between individuals in the same group. These differences have wide-ranging implications, affecting how groups make collective decisions and driving the evolution of collective motion. Here, I describe how trajectory data can be used to infer how animals interact in moving groups. I give examples of the similarities and differences in the spatial and directional organisations of animal groups between species, and discuss the rules that animals use to achieve this organisation. I then explore how groups of the same species can exhibit different structures, and ask whether this results from individuals adapting their interaction rules. I then examine how the interaction rules between individuals in the same groups can also differ, and discuss how this can affect ecological and evolutionary processes. Finally, I suggest areas of future research. PMID:27707862

  2. Understanding how animal groups achieve coordinated movement.

    PubMed

    Herbert-Read, J E

    2016-10-01

    Moving animal groups display remarkable feats of coordination. This coordination is largely achieved when individuals adjust their movement in response to their neighbours' movements and positions. Recent advancements in automated tracking technologies, including computer vision and GPS, now allow researchers to gather large amounts of data on the movements and positions of individuals in groups. Furthermore, analytical techniques from fields such as statistical physics now allow us to identify the precise interaction rules used by animals on the move. These interaction rules differ not only between species, but also between individuals in the same group. These differences have wide-ranging implications, affecting how groups make collective decisions and driving the evolution of collective motion. Here, I describe how trajectory data can be used to infer how animals interact in moving groups. I give examples of the similarities and differences in the spatial and directional organisations of animal groups between species, and discuss the rules that animals use to achieve this organisation. I then explore how groups of the same species can exhibit different structures, and ask whether this results from individuals adapting their interaction rules. I then examine how the interaction rules between individuals in the same groups can also differ, and discuss how this can affect ecological and evolutionary processes. Finally, I suggest areas of future research. © 2016. Published by The Company of Biologists Ltd.

  3. Ocean Tracking Network (OTN): Development of Oceanographic Data Integration with Animal Movement

    NASA Astrophysics Data System (ADS)

    Bajona, L.

    2016-02-01

    OTN is a $168-million ocean research and technology development platform headquartered at Dalhousie University, Canada. Using acoustic and satellite telemetry to globally document the movements and survival of aquatic animals, and their environmental correlates. The OTN Mission: to foster conservation and sustainability of valued species by generating knowledge on the movement patterns of aquatic species in their changing environment. OTN's ever-expanding global network of acoustic receivers listening for over 90 different key animal species is providing for the data needed in working in collaboration with researchers for the development of oceanographic data integration with animal movement. Presented here is Data Management's work to date, status and challenges in OTN's move towards a community standard to enable sharing between projects nationally and internationally; permitting inter-operability with other large national (e.g. CHONe, ArcticNET) and international (IOOS, IMOS) networks. This work includes co-development of Animal Acoustic Telemetry (AAT) metadata standard and implementation using an ERDDAP data server (NOAA, Environmental Research Division's Data Access Program) facilitating ingestion for modelers (eg. netcdf).

  4. Velocity-based movement modeling for individual and population level inference

    USGS Publications Warehouse

    Hanks, Ephraim M.; Hooten, Mevin B.; Johnson, Devin S.; Sterling, Jeremy T.

    2011-01-01

    Understanding animal movement and resource selection provides important information about the ecology of the animal, but an animal's movement and behavior are not typically constant in time. We present a velocity-based approach for modeling animal movement in space and time that allows for temporal heterogeneity in an animal's response to the environment, allows for temporal irregularity in telemetry data, and accounts for the uncertainty in the location information. Population-level inference on movement patterns and resource selection can then be made through cluster analysis of the parameters related to movement and behavior. We illustrate this approach through a study of northern fur seal (Callorhinus ursinus) movement in the Bering Sea, Alaska, USA. Results show sex differentiation, with female northern fur seals exhibiting stronger response to environmental variables.

  5. Velocity-Based Movement Modeling for Individual and Population Level Inference

    PubMed Central

    Hanks, Ephraim M.; Hooten, Mevin B.; Johnson, Devin S.; Sterling, Jeremy T.

    2011-01-01

    Understanding animal movement and resource selection provides important information about the ecology of the animal, but an animal's movement and behavior are not typically constant in time. We present a velocity-based approach for modeling animal movement in space and time that allows for temporal heterogeneity in an animal's response to the environment, allows for temporal irregularity in telemetry data, and accounts for the uncertainty in the location information. Population-level inference on movement patterns and resource selection can then be made through cluster analysis of the parameters related to movement and behavior. We illustrate this approach through a study of northern fur seal (Callorhinus ursinus) movement in the Bering Sea, Alaska, USA. Results show sex differentiation, with female northern fur seals exhibiting stronger response to environmental variables. PMID:21931584

  6. Equivalence between Step Selection Functions and Biased Correlated Random Walks for Statistical Inference on Animal Movement.

    PubMed

    Duchesne, Thierry; Fortin, Daniel; Rivest, Louis-Paul

    2015-01-01

    Animal movement has a fundamental impact on population and community structure and dynamics. Biased correlated random walks (BCRW) and step selection functions (SSF) are commonly used to study movements. Because no studies have contrasted the parameters and the statistical properties of their estimators for models constructed under these two Lagrangian approaches, it remains unclear whether or not they allow for similar inference. First, we used the Weak Law of Large Numbers to demonstrate that the log-likelihood function for estimating the parameters of BCRW models can be approximated by the log-likelihood of SSFs. Second, we illustrated the link between the two approaches by fitting BCRW with maximum likelihood and with SSF to simulated movement data in virtual environments and to the trajectory of bison (Bison bison L.) trails in natural landscapes. Using simulated and empirical data, we found that the parameters of a BCRW estimated directly from maximum likelihood and by fitting an SSF were remarkably similar. Movement analysis is increasingly used as a tool for understanding the influence of landscape properties on animal distribution. In the rapidly developing field of movement ecology, management and conservation biologists must decide which method they should implement to accurately assess the determinants of animal movement. We showed that BCRW and SSF can provide similar insights into the environmental features influencing animal movements. Both techniques have advantages. BCRW has already been extended to allow for multi-state modeling. Unlike BCRW, however, SSF can be estimated using most statistical packages, it can simultaneously evaluate habitat selection and movement biases, and can easily integrate a large number of movement taxes at multiple scales. SSF thus offers a simple, yet effective, statistical technique to identify movement taxis.

  7. Animal perception of seasonal thresholds: changes in elephant movement in relation to rainfall patterns.

    PubMed

    Birkett, Patricia J; Vanak, Abi T; Muggeo, Vito M R; Ferreira, Salamon M; Slotow, Rob

    2012-01-01

    The identification of temporal thresholds or shifts in animal movement informs ecologists of changes in an animal's behaviour, which contributes to an understanding of species' responses in different environments. In African savannas, rainfall, temperature and primary productivity influence the movements of large herbivores and drive changes at different scales. Here, we developed a novel approach to define seasonal shifts in movement behaviour by examining the movements of a highly mobile herbivore (elephant; Loxodonta africana), in relation to local and regional rainfall patterns. We used speed to determine movement changes of between 8 and 14 GPS-collared elephant cows, grouped into five spatial clusters, in Kruger National Park, South Africa. To detect broad-scale patterns of movement, we ran a three-year daily time-series model for each individual (2007-2009). Piecewise regression models provided the best fit for elephant movement, which exhibited a segmented, waveform pattern over time. Major breakpoints in speed occurred at the end of the dry and wet seasons of each year. During the dry season, female elephant are constrained by limited forage and thus the distances they cover are shorter and less variable. Despite the inter-annual variability of rainfall, speed breakpoints were strongly correlated with both local and regional rainfall breakpoints across all three years. Thus, at a multi-year scale, rainfall patterns significantly affect the movements of elephant. The variability of both speed and rainfall breakpoints across different years highlights the need for an objective definition of seasonal boundaries. By using objective criteria to determine behavioural shifts, we identified a biologically meaningful indicator of major changes in animal behaviour in different years. We recommend the use of such criteria, from an animal's perspective, for delineating seasons or other extrinsic shifts in ecological studies, rather than arbitrarily fixed definitions

  8. Simple models for studying complex spatiotemporal patterns of animal behavior

    NASA Astrophysics Data System (ADS)

    Tyutyunov, Yuri V.; Titova, Lyudmila I.

    2017-06-01

    Minimal mathematical models able to explain complex patterns of animal behavior are essential parts of simulation systems describing large-scale spatiotemporal dynamics of trophic communities, particularly those with wide-ranging species, such as occur in pelagic environments. We present results obtained with three different modelling approaches: (i) an individual-based model of animal spatial behavior; (ii) a continuous taxis-diffusion-reaction system of partial-difference equations; (iii) a 'hybrid' approach combining the individual-based algorithm of organism movements with explicit description of decay and diffusion of the movement stimuli. Though the models are based on extremely simple rules, they all allow description of spatial movements of animals in a predator-prey system within a closed habitat, reproducing some typical patterns of the pursuit-evasion behavior observed in natural populations. In all three models, at each spatial position the animal movements are determined by local conditions only, so the pattern of collective behavior emerges due to self-organization. The movement velocities of animals are proportional to the density gradients of specific cues emitted by individuals of the antagonistic species (pheromones, exometabolites or mechanical waves of the media, e.g., sound). These cues play a role of taxis stimuli: prey attract predators, while predators repel prey. Depending on the nature and the properties of the movement stimulus we propose using either a simplified individual-based model, a continuous taxis pursuit-evasion system, or a little more detailed 'hybrid' approach that combines simulation of the individual movements with the continuous model describing diffusion and decay of the stimuli in an explicit way. These can be used to improve movement models for many species, including large marine predators.

  9. A functional model for characterizing long-distance movement behaviour

    USGS Publications Warehouse

    Buderman, Frances E.; Hooten, Mevin B.; Ivan, Jacob S.; Shenk, Tanya M.

    2016-01-01

    Advancements in wildlife telemetry techniques have made it possible to collect large data sets of highly accurate animal locations at a fine temporal resolution. These data sets have prompted the development of a number of statistical methodologies for modelling animal movement.Telemetry data sets are often collected for purposes other than fine-scale movement analysis. These data sets may differ substantially from those that are collected with technologies suitable for fine-scale movement modelling and may consist of locations that are irregular in time, are temporally coarse or have large measurement error. These data sets are time-consuming and costly to collect but may still provide valuable information about movement behaviour.We developed a Bayesian movement model that accounts for error from multiple data sources as well as movement behaviour at different temporal scales. The Bayesian framework allows us to calculate derived quantities that describe temporally varying movement behaviour, such as residence time, speed and persistence in direction. The model is flexible, easy to implement and computationally efficient.We apply this model to data from Colorado Canada lynx (Lynx canadensis) and use derived quantities to identify changes in movement behaviour.

  10. Homogenization of a Directed Dispersal Model for Animal Movement in a Heterogeneous Environment.

    PubMed

    Yurk, Brian P

    2016-10-01

    The dispersal patterns of animals moving through heterogeneous environments have important ecological and epidemiological consequences. In this work, we apply the method of homogenization to analyze an advection-diffusion (AD) model of directed movement in a one-dimensional environment in which the scale of the heterogeneity is small relative to the spatial scale of interest. We show that the large (slow) scale behavior is described by a constant-coefficient diffusion equation under certain assumptions about the fast-scale advection velocity, and we determine a formula for the slow-scale diffusion coefficient in terms of the fast-scale parameters. We extend the homogenization result to predict invasion speeds for an advection-diffusion-reaction (ADR) model with directed dispersal. For periodic environments, the homogenization approximation of the solution of the AD model compares favorably with numerical simulations. Invasion speed approximations for the ADR model also compare favorably with numerical simulations when the spatial period is sufficiently small.

  11. Joint estimation over multiple individuals improves behavioural state inference from animal movement data.

    PubMed

    Jonsen, Ian

    2016-02-08

    State-space models provide a powerful way to scale up inference of movement behaviours from individuals to populations when the inference is made across multiple individuals. Here, I show how a joint estimation approach that assumes individuals share identical movement parameters can lead to improved inference of behavioural states associated with different movement processes. I use simulated movement paths with known behavioural states to compare estimation error between nonhierarchical and joint estimation formulations of an otherwise identical state-space model. Behavioural state estimation error was strongly affected by the degree of similarity between movement patterns characterising the behavioural states, with less error when movements were strongly dissimilar between states. The joint estimation model improved behavioural state estimation relative to the nonhierarchical model for simulated data with heavy-tailed Argos location errors. When applied to Argos telemetry datasets from 10 Weddell seals, the nonhierarchical model estimated highly uncertain behavioural state switching probabilities for most individuals whereas the joint estimation model yielded substantially less uncertainty. The joint estimation model better resolved the behavioural state sequences across all seals. Hierarchical or joint estimation models should be the preferred choice for estimating behavioural states from animal movement data, especially when location data are error-prone.

  12. Understanding the dynamical control of animal movement

    NASA Astrophysics Data System (ADS)

    Edwards, Donald

    2008-03-01

    Over the last 50 years, neurophysiologists have described many neural circuits that transform sensory input into motor commands, while biomechanicians and behavioral biologists have described many patterns of animal movement that occur in response to sensory input. Attempts to link these two have been frustrated by our technical inability to record from the necessary neurons in a freely behaving animal. As a result, we don't know how these neural circuits function in the closed loop context of free behavior, where the sensory and motor context changes on a millisecond time-scale. To address this problem, we have developed a software package, AnimatLab (www.AnimatLab.com), that enables users to reconstruct an animal's body and its relevant neural circuits, to link them at the sensory and motor ends, and through simulation, to test their ability to reproduce appropriate patterns of the animal's movements in a simulated Newtonian world. A Windows-based program, AnimatLab consists of a neural editor, a body editor, a world editor, stimulus and recording facilities, neural and physics engines, and an interactive 3-D graphical display. We have used AnimatLab to study three patterns of behavior: the grasshopper jump, crayfish escape, and crayfish leg movements used in postural control, walking, reaching and grasping. In each instance, the simulation helped identify constraints on both nervous function and biomechanical performance that have provided the basis for new experiments. Colleagues elsewhere have begun to use AnimatLab to study control of paw movements in cats and postural control in humans. We have also used AnimatLab simulations to guide the development of an autonomous hexapod robot in which the neural control circuitry is downloaded to the robot from the test computer.

  13. Group navigation and the "many-wrongs principle" in models of animal movement.

    PubMed

    Codling, E A; Pitchford, J W; Simpson, S D

    2007-07-01

    Traditional studies of animal navigation over both long and short distances have usually considered the orientation ability of the individual only, without reference to the implications of group membership. However, recent work has suggested that being in a group can significantly improve the ability of an individual to align toward and reach a target direction or point, even when all group members have limited navigational ability and there are no leaders. This effect is known as the "many-wrongs principle" since the large number of individual navigational errors across the group are suppressed by interactions and group cohesion. In this paper, we simulate the many-wrongs principle using a simple individual-based model of movement based on a biased random walk that includes group interactions. We study the ability of the group as a whole to reach a target given different levels of individual navigation error, group size, interaction radius, and environmental turbulence. In scenarios with low levels of environmental turbulence, simulation results demonstrate a navigational benefit from group membership, particularly for small group sizes. In contrast, when movement takes place in a highly turbulent environment, simulation results suggest that the best strategy is to navigate as individuals rather than as a group.

  14. Old models explain new observations of butterfly movement at patch edges.

    PubMed

    Crone, Elizabeth E; Schultz, Cheryl B

    2008-07-01

    Understanding movement in heterogeneous environments is central to predicting how landscape changes affect animal populations. Several recent studies point out an intriguing and distinctive looping behavior by butterflies at habitat patch edges and hypothesize that this behavior requires a new framework for analyzing animal movement. We show that this looping behavior could be caused by a longstanding movement model, biased correlated random walk, with bias toward habitat patches. The ability of this longstanding model to explain recent observations reinforces the point that butterflies respond to habitat heterogeneity and do not move randomly through heterogeneous environments. We discuss the implications of different movement models for predicting butterfly responses to landscape change, and our rationale for retaining longstanding movement models, rather than developing new modeling frameworks for looping behavior at patch edges.

  15. From moonlight to movement and synchronized randomness: Fourier and wavelet analyses of animal location time series data

    PubMed Central

    Polansky, Leo; Wittemyer, George; Cross, Paul C.; Tambling, Craig J.; Getz, Wayne M.

    2011-01-01

    High-resolution animal location data are increasingly available, requiring analytical approaches and statistical tools that can accommodate the temporal structure and transient dynamics (non-stationarity) inherent in natural systems. Traditional analyses often assume uncorrelated or weakly correlated temporal structure in the velocity (net displacement) time series constructed using sequential location data. We propose that frequency and time–frequency domain methods, embodied by Fourier and wavelet transforms, can serve as useful probes in early investigations of animal movement data, stimulating new ecological insight and questions. We introduce a novel movement model with time-varying parameters to study these methods in an animal movement context. Simulation studies show that the spectral signature given by these methods provides a useful approach for statistically detecting and characterizing temporal dependency in animal movement data. In addition, our simulations provide a connection between the spectral signatures observed in empirical data with null hypotheses about expected animal activity. Our analyses also show that there is not a specific one-to-one relationship between the spectral signatures and behavior type and that departures from the anticipated signatures are also informative. Box plots of net displacement arranged by time of day and conditioned on common spectral properties can help interpret the spectral signatures of empirical data. The first case study is based on the movement trajectory of a lion (Panthera leo) that shows several characteristic daily activity sequences, including an active–rest cycle that is correlated with moonlight brightness. A second example based on six pairs of African buffalo (Syncerus caffer) illustrates the use of wavelet coherency to show that their movements synchronize when they are within ∼1 km of each other, even when individual movement was best described as an uncorrelated random walk, providing an

  16. Applying Movement Ecology to Marine Animals with Complex Life Cycles.

    PubMed

    Allen, Richard M; Metaxas, Anna; Snelgrove, Paul V R

    2018-01-03

    Marine animals with complex life cycles may move passively or actively for fertilization, dispersal, predator avoidance, resource acquisition, and migration, and over scales from micrometers to thousands of kilometers. This diversity has catalyzed idiosyncratic and unfocused research, creating unsound paradigms regarding the role of movement in ecology and evolution. The emerging movement ecology paradigm offers a framework to consolidate movement research independent of taxon, life-history stage, scale, or discipline. This review applies the framework to movement among life-history stages in marine animals with complex life cycles to consolidate marine movement research and offer insights for scientists working in aquatic and terrestrial realms. Irrespective of data collection or simulation strategy, breaking each life-history stage down into the fundamental units of movement allows each unit to be studied independently or interactively with other units. Understanding these underlying mechanisms of movement within each life-history stage can then be used to construct lifetime movement paths. These paths can allow further investigation of the relative contributions and interdependencies of steps and phases across a lifetime and how these paths influence larger research topics, such as population-level movements.

  17. Applying Movement Ecology to Marine Animals with Complex Life Cycles

    NASA Astrophysics Data System (ADS)

    Allen, Richard M.; Metaxas, Anna; Snelgrove, Paul V. R.

    2018-01-01

    Marine animals with complex life cycles may move passively or actively for fertilization, dispersal, predator avoidance, resource acquisition, and migration, and over scales from micrometers to thousands of kilometers. This diversity has catalyzed idiosyncratic and unfocused research, creating unsound paradigms regarding the role of movement in ecology and evolution. The emerging movement ecology paradigm offers a framework to consolidate movement research independent of taxon, life-history stage, scale, or discipline. This review applies the framework to movement among life-history stages in marine animals with complex life cycles to consolidate marine movement research and offer insights for scientists working in aquatic and terrestrial realms. Irrespective of data collection or simulation strategy, breaking each life-history stage down into the fundamental units of movement allows each unit to be studied independently or interactively with other units. Understanding these underlying mechanisms of movement within each life-history stage can then be used to construct lifetime movement paths. These paths can allow further investigation of the relative contributions and interdependencies of steps and phases across a lifetime and how these paths influence larger research topics, such as population-level movements.

  18. Predicting the continuum between corridors and barriers to animal movements using Step Selection Functions and Randomized Shortest Paths.

    PubMed

    Panzacchi, Manuela; Van Moorter, Bram; Strand, Olav; Saerens, Marco; Kivimäki, Ilkka; St Clair, Colleen C; Herfindal, Ivar; Boitani, Luigi

    2016-01-01

    The loss, fragmentation and degradation of habitat everywhere on Earth prompts increasing attention to identifying landscape features that support animal movement (corridors) or impedes it (barriers). Most algorithms used to predict corridors assume that animals move through preferred habitat either optimally (e.g. least cost path) or as random walkers (e.g. current models), but neither extreme is realistic. We propose that corridors and barriers are two sides of the same coin and that animals experience landscapes as spatiotemporally dynamic corridor-barrier continua connecting (separating) functional areas where individuals fulfil specific ecological processes. Based on this conceptual framework, we propose a novel methodological approach that uses high-resolution individual-based movement data to predict corridor-barrier continua with increased realism. Our approach consists of two innovations. First, we use step selection functions (SSF) to predict friction maps quantifying corridor-barrier continua for tactical steps between consecutive locations. Secondly, we introduce to movement ecology the randomized shortest path algorithm (RSP) which operates on friction maps to predict the corridor-barrier continuum for strategic movements between functional areas. By modulating the parameter Ѳ, which controls the trade-off between exploration and optimal exploitation of the environment, RSP bridges the gap between algorithms assuming optimal movements (when Ѳ approaches infinity, RSP is equivalent to LCP) or random walk (when Ѳ → 0, RSP → current models). Using this approach, we identify migration corridors for GPS-monitored wild reindeer (Rangifer t. tarandus) in Norway. We demonstrate that reindeer movement is best predicted by an intermediate value of Ѳ, indicative of a movement trade-off between optimization and exploration. Model calibration allows identification of a corridor-barrier continuum that closely fits empirical data and demonstrates that RSP

  19. Movement rules for individual-based models of stream fish

    Treesearch

    Steven F. Railsback; Roland H. Lamberson; Bret C. Harvey; Walter E. Duffy

    1999-01-01

    Abstract - Spatially explicit individual-based models (IBMs) use movement rules to determine when an animal departs its current location and to determine its movement destination; these rules are therefore critical to accurate simulations. Movement rules typically define some measure of how an individual's expected fitness varies among locations, under the...

  20. Movement of regulatory RNA between animal cells.

    PubMed

    Jose, Antony M

    2015-07-01

    Recent studies suggest that RNA can move from one cell to another and regulate genes through specific base-pairing. Mechanisms that modify or select RNA for secretion from a cell are unclear. Secreted RNA can be stable enough to be detected in the extracellular environment and can enter the cytosol of distant cells to regulate genes. Mechanisms that import RNA into the cytosol of an animal cell can enable uptake of RNA from many sources including other organisms. This role of RNA is akin to that of steroid hormones, which cross cell membranes to regulate genes. The potential diagnostic use of RNA in human extracellular fluids has ignited interest in understanding mechanisms that enable the movement of RNA between animal cells. Genetic model systems will be essential to gain more confidence in proposed mechanisms of RNA transport and to connect an extracellular RNA with a specific biological function. Studies in the worm C. elegans and in other animals have begun to reveal parts of this novel mechanism of cell-to-cell communication. Here, I summarize the current state of this nascent field, highlight the many unknowns, and suggest future directions. © 2015 Wiley Periodicals, Inc.

  1. 9 CFR 94.15 - Animal products and materials; movement and handling.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Animal products and materials; movement and handling. 94.15 Section 94.15 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL...

  2. 9 CFR 94.15 - Animal products and materials; movement and handling.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Animal products and materials; movement and handling. 94.15 Section 94.15 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL...

  3. Accounting for animal movement in estimation of resource selection functions: sampling and data analysis.

    PubMed

    Forester, James D; Im, Hae Kyung; Rathouz, Paul J

    2009-12-01

    Patterns of resource selection by animal populations emerge as a result of the behavior of many individuals. Statistical models that describe these population-level patterns of habitat use can miss important interactions between individual animals and characteristics of their local environment; however, identifying these interactions is difficult. One approach to this problem is to incorporate models of individual movement into resource selection models. To do this, we propose a model for step selection functions (SSF) that is composed of a resource-independent movement kernel and a resource selection function (RSF). We show that standard case-control logistic regression may be used to fit the SSF; however, the sampling scheme used to generate control points (i.e., the definition of availability) must be accommodated. We used three sampling schemes to analyze simulated movement data and found that ignoring sampling and the resource-independent movement kernel yielded biased estimates of selection. The level of bias depended on the method used to generate control locations, the strength of selection, and the spatial scale of the resource map. Using empirical or parametric methods to sample control locations produced biased estimates under stronger selection; however, we show that the addition of a distance function to the analysis substantially reduced that bias. Assuming a uniform availability within a fixed buffer yielded strongly biased selection estimates that could be corrected by including the distance function but remained inefficient relative to the empirical and parametric sampling methods. As a case study, we used location data collected from elk in Yellowstone National Park, USA, to show that selection and bias may be temporally variable. Because under constant selection the amount of bias depends on the scale at which a resource is distributed in the landscape, we suggest that distance always be included as a covariate in SSF analyses. This approach to

  4. Discovering loose group movement patterns from animal trajectories

    USGS Publications Warehouse

    Wang, Yuwei; Luo, Ze; Xiong, Yan; Prosser, Diann J.; Newman, Scott H.; Takekawa, John Y.; Yan, Baoping

    2015-01-01

    The technical advances of positioning technologies enable us to track animal movements at finer spatial and temporal scales, and further help to discover a variety of complex interactive relationships. In this paper, considering the loose gathering characteristics of the real-life groups' members during the movements, we propose two kinds of loose group movement patterns and corresponding discovery algorithms. Firstly, we propose the weakly consistent group movement pattern which allows the gathering of a part of the members and individual temporary leave from the whole during the movements. To tolerate the high dispersion of the group at some moments (i.e. to adapt the discontinuity of the group's gatherings), we further scheme the weakly consistent and continuous group movement pattern. The extensive experimental analysis and comparison with the real and synthetic data shows that the group pattern discovery algorithms proposed in this paper are similar to the the real-life frequent divergences of the members during the movements, can discover more complete memberships, and have considerable performance.

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

    PubMed

    Tilles, Paulo F C; Petrovskii, Sergei V

    2016-07-01

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

  6. Classification of Animal Movement Behavior through Residence in Space and Time.

    PubMed

    Torres, Leigh G; Orben, Rachael A; Tolkova, Irina; Thompson, David R

    2017-01-01

    Identification and classification of behavior states in animal movement data can be complex, temporally biased, time-intensive, scale-dependent, and unstandardized across studies and taxa. Large movement datasets are increasingly common and there is a need for efficient methods of data exploration that adjust to the individual variability of each track. We present the Residence in Space and Time (RST) method to classify behavior patterns in movement data based on the concept that behavior states can be partitioned by the amount of space and time occupied in an area of constant scale. Using normalized values of Residence Time and Residence Distance within a constant search radius, RST is able to differentiate behavior patterns that are time-intensive (e.g., rest), time & distance-intensive (e.g., area restricted search), and transit (short time and distance). We use grey-headed albatross (Thalassarche chrysostoma) GPS tracks to demonstrate RST's ability to classify behavior patterns and adjust to the inherent scale and individuality of each track. Next, we evaluate RST's ability to discriminate between behavior states relative to other classical movement metrics. We then temporally sub-sample albatross track data to illustrate RST's response to less resolved data. Finally, we evaluate RST's performance using datasets from four taxa with diverse ecology, functional scales, ecosystems, and data-types. We conclude that RST is a robust, rapid, and flexible method for detailed exploratory analysis and meta-analyses of behavioral states in animal movement data based on its ability to integrate distance and time measurements into one descriptive metric of behavior groupings. Given the increasing amount of animal movement data collected, it is timely and useful to implement a consistent metric of behavior classification to enable efficient and comparative analyses. Overall, the application of RST to objectively explore and compare behavior patterns in movement data can

  7. 9 CFR 71.16 - Inspection and certification of poultry or other animals for interstate movement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... poultry or other animals for interstate movement. 71.16 Section 71.16 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS GENERAL PROVISIONS § 71.16 Inspection and certification of poultry or other animals for interstate movement. (a) Assistance and facilities. When poultry or other animals are...

  8. 9 CFR 72.1 - Interstate movement of infested or exposed animals prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Interstate movement of infested or exposed animals prohibited. 72.1 Section 72.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND...

  9. Generation of animation sequences of three dimensional models

    NASA Technical Reports Server (NTRS)

    Poi, Sharon (Inventor); Bell, Brad N. (Inventor)

    1990-01-01

    The invention is directed toward a method and apparatus for generating an animated sequence through the movement of three-dimensional graphical models. A plurality of pre-defined graphical models are stored and manipulated in response to interactive commands or by means of a pre-defined command file. The models may be combined as part of a hierarchical structure to represent physical systems without need to create a separate model which represents the combined system. System motion is simulated through the introduction of translation, rotation and scaling parameters upon a model within the system. The motion is then transmitted down through the system hierarchy of models in accordance with hierarchical definitions and joint movement limitations. The present invention also calls for a method of editing hierarchical structure in response to interactive commands or a command file such that a model may be included, deleted, copied or moved within multiple system model hierarchies. The present invention also calls for the definition of multiple viewpoints or cameras which may exist as part of a system hierarchy or as an independent camera. The simulated movement of the models and systems is graphically displayed on a monitor and a frame is recorded by means of a video controller. Multiple movement and hierarchy manipulations are then recorded as a sequence of frames which may be played back as an animation sequence on a video cassette recorder.

  10. MOAB: a spatially explicit, individual-based expert system for creating animal foraging models

    USGS Publications Warehouse

    Carter, J.; Finn, John T.

    1999-01-01

    We describe the development, structure, and corroboration process of a simulation model of animal behavior (MOAB). MOAB can create spatially explicit, individual-based animal foraging models. Users can create or replicate heterogeneous landscape patterns, and place resources and individual animals of a goven species on that landscape to simultaneously simulate the foraging behavior of multiple species. The heuristic rules for animal behavior are maintained in a user-modifiable expert system. MOAB can be used to explore hypotheses concerning the influence of landscape patttern on animal movement and foraging behavior. A red fox (Vulpes vulpes L.) foraging and nest predation model was created to test MOAB's capabilities. Foxes were simulated for 30-day periods using both expert system and random movement rules. Home range size, territory formation and other available simulation studies. A striped skunk (Mephitis mephitis L.) model also was developed. The expert system model proved superior to stochastic in respect to territory formation, general movement patterns and home range size.

  11. Apparent power-law distributions in animal movements can arise from intraspecific interactions

    PubMed Central

    Breed, Greg A.; Severns, Paul M.; Edwards, Andrew M.

    2015-01-01

    Lévy flights have gained prominence for analysis of animal movement. In a Lévy flight, step-lengths are drawn from a heavy-tailed distribution such as a power law (PL), and a large number of empirical demonstrations have been published. Others, however, have suggested that animal movement is ill fit by PL distributions or contend a state-switching process better explains apparent Lévy flight movement patterns. We used a mix of direct behavioural observations and GPS tracking to understand step-length patterns in females of two related butterflies. We initially found movement in one species (Euphydryas editha taylori) was best fit by a bounded PL, evidence of a Lévy flight, while the other (Euphydryas phaeton) was best fit by an exponential distribution. Subsequent analyses introduced additional candidate models and used behavioural observations to sort steps based on intraspecific interactions (interactions were rare in E. phaeton but common in E. e. taylori). These analyses showed a mixed-exponential is favoured over the bounded PL for E. e. taylori and that when step-lengths were sorted into states based on the influence of harassing conspecific males, both states were best fit by simple exponential distributions. The direct behavioural observations allowed us to infer the underlying behavioural mechanism is a state-switching process driven by intraspecific interactions rather than a Lévy flight. PMID:25519992

  12. Estimating the scale of adverse animal welfare consequences of movement restriction and mitigation strategies in a classical swine fever outbreak.

    PubMed

    Yadav, Shankar; Weng, Hsin-Yi

    2017-04-04

    The study aim was to quantify the impact of movement restriction on the well-being of pigs and the associated mitigation responses during a classical swine fever (CSF) outbreak. We developed a stochastic risk assessment model and incorporated Indiana swine industry statistics to estimate the timing and number of swine premises that would encounter overcrowding or feed interruption resulting from movement restriction. Our model also quantified the amount of on-farm euthanasia and movement of pigs to slaughter plants required to alleviate those conditions. We simulated various single-site (i.e., an outbreak initiated from one location) and multiple-site (i.e., an outbreak initiated from more than one location) outbreak scenarios in Indiana to estimate outputs. The study estimated that 14% of the swine premises in Indiana would encounter overcrowding or feed interruption due to movement restriction implemented during a CSF outbreak. The number of premises that would experience animal welfare conditions was about 2.5 fold of the number of infected premises. On-farm euthanasia needed to be performed on 33% of those swine premises to alleviate adverse animal welfare conditions, and more than 90% of on-farm euthanasia had to be carried out within 2 weeks after the implementation of movement restriction. Conversely, movement of pigs to slaughter plants could alleviate 67% of adverse animal welfare conditions due to movement restriction, and only less than 1% of movement of pigs to slaughter plants had to be initiated in the first 2 weeks of movement restrictions. The risk of secondary outbreaks due to movement of pigs from movement restriction areas to slaughter plants was low and only seven pigs from each shipment needed to be tested for CSF infection to prevent a secondary outbreak. We found that the scale of adverse animal welfare consequences of movement restriction during a CSF outbreak in Indiana was substantial, and controlled movement of pigs to slaughter plants

  13. 9 CFR 71.2 - Secretary to issue rule governing quarantine and interstate movement of diseased animals...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... quarantine and interstate movement of diseased animals, including poultry. 71.2 Section 71.2 Animals and... TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS GENERAL PROVISIONS § 71.2 Secretary to issue rule governing quarantine and interstate movement of diseased animals, including poultry. When the...

  14. Agent Based Model of Livestock Movements

    NASA Astrophysics Data System (ADS)

    Miron, D. J.; Emelyanova, I. V.; Donald, G. E.; Garner, G. M.

    The modelling of livestock movements within Australia is of national importance for the purposes of the management and control of exotic disease spread, infrastructure development and the economic forecasting of livestock markets. In this paper an agent based model for the forecasting of livestock movements is presented. This models livestock movements from farm to farm through a saleyard. The decision of farmers to sell or buy cattle is often complex and involves many factors such as climate forecast, commodity prices, the type of farm enterprise, the number of animals available and associated off-shore effects. In this model the farm agent's intelligence is implemented using a fuzzy decision tree that utilises two of these factors. These two factors are the livestock price fetched at the last sale and the number of stock on the farm. On each iteration of the model farms choose either to buy, sell or abstain from the market thus creating an artificial supply and demand. The buyers and sellers then congregate at the saleyard where livestock are auctioned using a second price sealed bid. The price time series output by the model exhibits properties similar to those found in real livestock markets.

  15. 9 CFR 71.3 - Interstate movement of diseased animals and poultry generally prohibited.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Interstate movement of diseased animals and poultry generally prohibited. 71.3 Section 71.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING...

  16. 9 CFR 71.3 - Interstate movement of diseased animals and poultry generally prohibited.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Interstate movement of diseased animals and poultry generally prohibited. 71.3 Section 71.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING...

  17. Dissemination of parasites by animal movements in small ruminant farms.

    PubMed

    Vasileiou, N G C; Fthenakis, G C; Papadopoulos, E

    2015-09-30

    The present paper discusses the spread of parasites by animal movements in small ruminant farms; it focuses in dissemination of parasitic forms that would lead to subsequent infection of sheep or goats. Systems of small ruminant production involve a component of animal movement (e.g., grazing) as part of routine husbandry, which favors spread of parasitic forms; that refers mainly to parasites of the digestive system (nematodes, trematodes, cestodes, protozoa), as well as helminthes of the respiratory system, although dissemination of the various parasitic forms in the environment would not always result to subsequent infection; external parasites may also be disseminated during movements, e.g., to inhabit wooden poles used in fencing. New livestock into a farm constitutes a biosecurity hazard and the most common means to introducing new parasitic pathogens into a farm; in contemporary small ruminant health management, this contributes in dissemination of anthelmintic resistant parasitic strains; other parasitic disease agents (e.g., mange mites, ticks) may also be spread into a farm that way. Often, especially in small scale farming, visits of rams or bucks take place from one farm to another during the mating season; in such cases, ectoparasites (e.g., mange mites) can be disseminated through direct contact of animals, as well other pathogens (e.g., Toxoplasma gondii, Neospora caninum) via the semen. During transportation of sheep/goats, parasitic forms can also spread, as well as during movement of sheep or goats to slaughterhouses, in which case dogs present in these places would contribute to their dissemination. Spread of life forms of various parasites can also occur from animal species present in the environment of sheep or goats; these include animals present within a farm, stray dogs roaming around a farm (e.g., for spread of Multiceps multiceps, Echinococcus granulosus, Taenia hydatigena, N. caninum), cats commanding the environment of a farm (e.g., for

  18. Deriving movement properties and the effect of the environment from the Brownian bridge movement model in monkeys and birds.

    PubMed

    Buchin, Kevin; Sijben, Stef; van Loon, E Emiel; Sapir, Nir; Mercier, Stéphanie; Marie Arseneau, T Jean; Willems, Erik P

    2015-01-01

    The Brownian bridge movement model (BBMM) provides a biologically sound approximation of the movement path of an animal based on discrete location data, and is a powerful method to quantify utilization distributions. Computing the utilization distribution based on the BBMM while calculating movement parameters directly from the location data, may result in inconsistent and misleading results. We show how the BBMM can be extended to also calculate derived movement parameters. Furthermore we demonstrate how to integrate environmental context into a BBMM-based analysis. We develop a computational framework to analyze animal movement based on the BBMM. In particular, we demonstrate how a derived movement parameter (relative speed) and its spatial distribution can be calculated in the BBMM. We show how to integrate our framework with the conceptual framework of the movement ecology paradigm in two related but acutely different ways, focusing on the influence that the environment has on animal movement. First, we demonstrate an a posteriori approach, in which the spatial distribution of average relative movement speed as obtained from a "contextually naïve" model is related to the local vegetation structure within the monthly ranging area of a group of wild vervet monkeys. Without a model like the BBMM it would not be possible to estimate such a spatial distribution of a parameter in a sound way. Second, we introduce an a priori approach in which atmospheric information is used to calculate a crucial parameter of the BBMM to investigate flight properties of migrating bee-eaters. This analysis shows significant differences in the characteristics of flight modes, which would have not been detected without using the BBMM. Our algorithm is the first of its kind to allow BBMM-based computation of movement parameters beyond the utilization distribution, and we present two case studies that demonstrate two fundamentally different ways in which our algorithm can be applied to

  19. Understanding movement data and movement processes: current and emerging directions.

    PubMed

    Schick, Robert S; Loarie, Scott R; Colchero, Fernando; Best, Benjamin D; Boustany, Andre; Conde, Dalia A; Halpin, Patrick N; Joppa, Lucas N; McClellan, Catherine M; Clark, James S

    2008-12-01

    Animal movement has been the focus on much theoretical and empirical work in ecology over the last 25 years. By studying the causes and consequences of individual movement, ecologists have gained greater insight into the behavior of individuals and the spatial dynamics of populations at increasingly higher levels of organization. In particular, ecologists have focused on the interaction between individuals and their environment in an effort to understand future impacts from habitat loss and climate change. Tools to examine this interaction have included: fractal analysis, first passage time, Lévy flights, multi-behavioral analysis, hidden markov models, and state-space models. Concurrent with the development of movement models has been an increase in the sophistication and availability of hierarchical bayesian models. In this review we bring these two threads together by using hierarchical structures as a framework for reviewing individual models. We synthesize emerging themes in movement ecology, and propose a new hierarchical model for animal movement that builds on these emerging themes. This model moves away from traditional random walks, and instead focuses inference on how moving animals with complex behavior interact with their landscape and make choices about its suitability.

  20. 9 CFR 80.4 - Segregation of animals positive to an official Johne's disease test during interstate movement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... official Johne's disease test during interstate movement. 80.4 Section 80.4 Animals and Animal Products... ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.4 Segregation of animals positive to an official Johne's disease test during interstate movement. Animals that are positive...

  1. 9 CFR 80.4 - Segregation of animals positive to an official Johne's disease test during interstate movement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... official Johne's disease test during interstate movement. 80.4 Section 80.4 Animals and Animal Products... ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.4 Segregation of animals positive to an official Johne's disease test during interstate movement. Animals that are positive...

  2. 9 CFR 80.4 - Segregation of animals positive to an official Johne's disease test during interstate movement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... official Johne's disease test during interstate movement. 80.4 Section 80.4 Animals and Animal Products... ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.4 Segregation of animals positive to an official Johne's disease test during interstate movement. Animals that are positive...

  3. 9 CFR 80.4 - Segregation of animals positive to an official Johne's disease test during interstate movement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... official Johne's disease test during interstate movement. 80.4 Section 80.4 Animals and Animal Products... ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.4 Segregation of animals positive to an official Johne's disease test during interstate movement. Animals that are positive...

  4. 9 CFR 80.4 - Segregation of animals positive to an official Johne's disease test during interstate movement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... official Johne's disease test during interstate movement. 80.4 Section 80.4 Animals and Animal Products... ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.4 Segregation of animals positive to an official Johne's disease test during interstate movement. Animals that are positive...

  5. 9 CFR 78.2 - Handling of certificates, permits, and “S” brand permits for interstate movement of animals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... âSâ brand permits for interstate movement of animals. 78.2 Section 78.2 Animals and Animal Products... certificates, permits, and “S” brand permits for interstate movement of animals. (a) Any certificate, permit, or “S” brand permit required by this part for the interstate movement of animals shall be delivered...

  6. Computer-animated model of accommodation and presbyopia.

    PubMed

    Goldberg, Daniel B

    2015-02-01

    To understand, demonstrate, and further research the mechanisms of accommodation and presbyopia. Private practice, Little Silver, New Jersey, USA. Experimental study. The CAMA 2.0 computer-animated model of accommodation and presbyopia was produced in collaboration with an experienced medical animator using Autodesk Maya animation software and Adobe After Effects. The computer-animated model demonstrates the configuration and synchronous movements of all accommodative elements. A new classification of the zonular apparatus based on structure and function is proposed. There are 3 divisions of zonular fibers; that is, anterior, crossing, and posterior. The crossing zonular fibers form a scaffolding to support the lens; the anterior and posterior zonular fibers work reciprocally to achieve focused vision. The model demonstrates the important support function of Weiger ligament. Dynamic movement of the ora serrata demonstrates that the forces of ciliary muscle contraction store energy for disaccommodation in the elastic choroid. The flow of aqueous and vitreous provides strong evidence for our understanding of the hydrodynamic interactions during the accommodative cycle. The interaction may result from the elastic stretch in the choroid transmitted to the vitreous rather than from vitreous pressue. The model supports the concept that presbyopia results from loss of elasticity and increasing ocular rigidity in both the lenticular and extralenticular structures. The computer-animated model demonstrates the structures of accommodation moving in synchrony and might enhance understanding of the mechanisms of accommodation and presbyopia. Dr. Goldberg is a consultant to Acevision, Inc., and Bausch & Lomb. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  7. 9 CFR 80.3 - Movement of domestic animals that are positive to an official Johne's disease test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... positive to an official Johne's disease test. 80.3 Section 80.3 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.3 Movement of domestic animals that are positive to an official Johne's disease test. (a) Movement of domestic animals for...

  8. 9 CFR 80.3 - Movement of domestic animals that are positive to an official Johne's disease test.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... positive to an official Johne's disease test. 80.3 Section 80.3 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.3 Movement of domestic animals that are positive to an official Johne's disease test. (a) Movement of domestic animals for...

  9. 9 CFR 80.3 - Movement of domestic animals that are positive to an official Johne's disease test.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... positive to an official Johne's disease test. 80.3 Section 80.3 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.3 Movement of domestic animals that are positive to an official Johne's disease test. (a) Movement of domestic animals for...

  10. 9 CFR 80.3 - Movement of domestic animals that are positive to an official Johne's disease test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... positive to an official Johne's disease test. 80.3 Section 80.3 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.3 Movement of domestic animals that are positive to an official Johne's disease test. (a) Movement of domestic animals for...

  11. 9 CFR 80.3 - Movement of domestic animals that are positive to an official Johne's disease test.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... positive to an official Johne's disease test. 80.3 Section 80.3 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS JOHNE'S DISEASE IN DOMESTIC ANIMALS § 80.3 Movement of domestic animals that are positive to an official Johne's disease test. (a) Movement of domestic animals for...

  12. Relationship of trade patterns of the Danish swine industry animal movements network to potential disease spread.

    PubMed

    Bigras-Poulin, Michel; Barfod, Kristen; Mortensen, Sten; Greiner, Matthias

    2007-07-16

    The movements of animals were analysed under the conceptual framework of graph theory in mathematics. The swine production related premises of Denmark were considered to constitute the nodes of a network and the links were the animal movements. In this framework, each farm will have a network of other premises to which it will be linked. A premise was a farm (breeding, rearing or slaughter pig), an abattoir or a trade market. The overall network was divided in premise specific subnets that linked the other premises from and to which animals were moved. This approach allowed us to visualise and analyse the three levels of organization related to animal movements that existed in the Danish swine production registers: the movement of animals between two premises, the premise specific networks, and the industry network. The analyses of animal movements were done using these three levels of organisation. The movements of swine were studied for the period September 30, 2002 to May 22, 2003. For daily movements of swine between two slaughter pig premises, the median number of pigs moved was 130 pigs with a maximum of 3306. For movements between a slaughter pig premise and an abattoir, the median number of pigs was 24. The largest percentage of movements was from farm to abattoir (82.5%); the median number of pigs per movement was 24 and the maximum number was 2018. For the whole period the median and maximum Euclidean distances observed in farm-to-farm movements were 22 km and 289 km respectively, while in the farm-to-abattoir movements, they were 36.2 km and 285 km. The network related to one specific premise showed that the median number of premises was mainly away from slaughter pig farms (3) or breeder farms (26) and mainly to an abattoir (1535). The assumption that animal movements can be randomly generated on the basis of farm density of the surrounding area of any farm is not correct since the patterns of animal movements have the topology of a scale-free network

  13. Dystonia and Paroxysmal Dyskinesias: Under-Recognized Movement Disorders in Domestic Animals? A Comparison with Human Dystonia/Paroxysmal Dyskinesias

    PubMed Central

    Richter, Angelika; Hamann, Melanie; Wissel, Jörg; Volk, Holger A.

    2015-01-01

    Dystonia is defined as a neurological syndrome characterized by involuntary sustained or intermittent muscle contractions causing twisting, often repetitive movements, and postures. Paroxysmal dyskinesias are episodic movement disorders encompassing dystonia, chorea, athetosis, and ballism in conscious individuals. Several decades of research have enhanced the understanding of the etiology of human dystonia and dyskinesias that are associated with dystonia, but the pathophysiology remains largely unknown. The spontaneous occurrence of hereditary dystonia and paroxysmal dyskinesia is well documented in rodents used as animal models in basic dystonia research. Several hyperkinetic movement disorders, described in dogs, horses and cattle, show similarities to these human movement disorders. Although dystonia is regarded as the third most common movement disorder in humans, it is often misdiagnosed because of the heterogeneity of etiology and clinical presentation. Since these conditions are poorly known in veterinary practice, their prevalence may be underestimated in veterinary medicine. In order to attract attention to these movement disorders, i.e., dystonia and paroxysmal dyskinesias associated with dystonia, and to enhance interest in translational research, this review gives a brief overview of the current literature regarding dystonia/paroxysmal dyskinesia in humans and summarizes similar hereditary movement disorders reported in domestic animals. PMID:26664992

  14. Dystonia and Paroxysmal Dyskinesias: Under-Recognized Movement Disorders in Domestic Animals? A Comparison with Human Dystonia/Paroxysmal Dyskinesias.

    PubMed

    Richter, Angelika; Hamann, Melanie; Wissel, Jörg; Volk, Holger A

    2015-01-01

    Dystonia is defined as a neurological syndrome characterized by involuntary sustained or intermittent muscle contractions causing twisting, often repetitive movements, and postures. Paroxysmal dyskinesias are episodic movement disorders encompassing dystonia, chorea, athetosis, and ballism in conscious individuals. Several decades of research have enhanced the understanding of the etiology of human dystonia and dyskinesias that are associated with dystonia, but the pathophysiology remains largely unknown. The spontaneous occurrence of hereditary dystonia and paroxysmal dyskinesia is well documented in rodents used as animal models in basic dystonia research. Several hyperkinetic movement disorders, described in dogs, horses and cattle, show similarities to these human movement disorders. Although dystonia is regarded as the third most common movement disorder in humans, it is often misdiagnosed because of the heterogeneity of etiology and clinical presentation. Since these conditions are poorly known in veterinary practice, their prevalence may be underestimated in veterinary medicine. In order to attract attention to these movement disorders, i.e., dystonia and paroxysmal dyskinesias associated with dystonia, and to enhance interest in translational research, this review gives a brief overview of the current literature regarding dystonia/paroxysmal dyskinesia in humans and summarizes similar hereditary movement disorders reported in domestic animals.

  15. Toward the quantification of a conceptual framework for movement ecology using circular statistical modeling.

    PubMed

    Shimatani, Ichiro Ken; Yoda, Ken; Katsumata, Nobuhiro; Sato, Katsufumi

    2012-01-01

    To analyze an animal's movement trajectory, a basic model is required that satisfies the following conditions: the model must have an ecological basis and the parameters used in the model must have ecological interpretations, a broad range of movement patterns can be explained by that model, and equations and probability distributions in the model should be mathematically tractable. Random walk models used in previous studies do not necessarily satisfy these requirements, partly because movement trajectories are often more oriented or tortuous than expected from the models. By improving the modeling for turning angles, this study aims to propose a basic movement model. On the basis of the recently developed circular auto-regressive model, we introduced a new movement model and extended its applicability to capture the asymmetric effects of external factors such as wind. The model was applied to GPS trajectories of a seabird (Calonectris leucomelas) to demonstrate its applicability to various movement patterns and to explain how the model parameters are ecologically interpreted under a general conceptual framework for movement ecology. Although it is based on a simple extension of a generalized linear model to circular variables, the proposed model enables us to evaluate the effects of external factors on movement separately from the animal's internal state. For example, maximum likelihood estimates and model selection suggested that in one homing flight section, the seabird intended to fly toward the island, but misjudged its navigation and was driven off-course by strong winds, while in the subsequent flight section, the seabird reset the focal direction, navigated the flight under strong wind conditions, and succeeded in approaching the island.

  16. Quantifying animal movement for caching foragers: the path identification index (PII) and cougars, Puma concolor.

    PubMed

    Ironside, Kirsten E; Mattson, David J; Theimer, Tad; Jansen, Brian; Holton, Brandon; Arundel, Terence; Peters, Michael; Sexton, Joseph O; Edwards, Thomas C

    2017-01-01

    Many studies of animal movement have focused on directed versus area-restricted movement, which rely on correlations between step-length and turn-angles and on stationarity through time to define behavioral states. Although these approaches might apply well to grazing in patchy landscapes, species that either feed for short periods on large, concentrated food sources or cache food exhibit movements that are difficult to model using the traditional metrics of turn-angle and step-length alone. We used GPS telemetry collected from a prey-caching predator, the cougar ( Puma concolor, Linnaeus ), to test whether combining metrics of site recursion, spatiotemporal clustering, speed, and turning into an index of movement using partial sums, improves the ability to identify caching behavior. The index was used to identify changes in movement characteristics over time and segment paths into behavioral classes. The identification of behaviors from the Path Identification Index (PII) was evaluated using field investigations of cougar activities at GPS locations. We tested for statistical stationarity across behaviors for use of topographic view-sheds. Changes in the frequency and duration of PII were useful for identifying seasonal activities such as migration, gestation, and denning. The comparison of field investigations of cougar activities to behavioral PII classes resulted in an overall classification accuracy of 81%. Changes in behaviors were reflected in cougars' use of topographic view-sheds, resulting in statistical nonstationarity over time, and revealed important aspects of hunting behavior. Incorporating metrics of site recursion and spatiotemporal clustering revealed the temporal structure in movements of a caching forager. The movement index PII, shows promise for identifying behaviors in species that frequently return to specific locations such as food caches, watering holes, or dens, and highlights the potential role memory and cognitive abilities play in

  17. 9 CFR 71.16 - Inspection and certification of poultry or other animals for interstate movement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Inspection and certification of poultry or other animals for interstate movement. 71.16 Section 71.16 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS...

  18. 9 CFR 71.16 - Inspection and certification of poultry or other animals for interstate movement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Inspection and certification of poultry or other animals for interstate movement. 71.16 Section 71.16 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS...

  19. 9 CFR 71.16 - Inspection and certification of poultry or other animals for interstate movement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Inspection and certification of poultry or other animals for interstate movement. 71.16 Section 71.16 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS...

  20. 9 CFR 71.16 - Inspection and certification of poultry or other animals for interstate movement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Inspection and certification of poultry or other animals for interstate movement. 71.16 Section 71.16 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS...

  1. An individual-based model of skipjack tuna (Katsuwonus pelamis) movement in the tropical Pacific ocean

    NASA Astrophysics Data System (ADS)

    Scutt Phillips, Joe; Sen Gupta, Alex; Senina, Inna; van Sebille, Erik; Lange, Michael; Lehodey, Patrick; Hampton, John; Nicol, Simon

    2018-05-01

    The distribution of marine species is often modeled using Eulerian approaches, in which changes to population density or abundance are calculated at fixed locations in space. Conversely, Lagrangian, or individual-based, models simulate the movement of individual particles moving in continuous space, with broader-scale patterns such as distribution being an emergent property of many, potentially adaptive, individuals. These models offer advantages in examining dynamics across spatiotemporal scales and making comparisons with observations from individual-scale data. Here, we introduce and describe such a model, the Individual-based Kinesis, Advection and Movement of Ocean ANimAls model (Ikamoana), which we use to replicate the movement processes of an existing Eulerian model for marine predators (the Spatial Ecosystem and Population Dynamics Model, SEAPODYM). Ikamoana simulates the movement of either individual or groups of animals by physical ocean currents, habitat-dependent stochastic movements (kinesis), and taxis movements representing active searching behaviours. Applying our model to Pacific skipjack tuna (Katsuwonus pelamis), we show that it accurately replicates the evolution of density distribution simulated by SEAPODYM with low time-mean error and a spatial correlation of density that exceeds 0.96 at all times. We demonstrate how the Lagrangian approach permits easy tracking of individuals' trajectories for examining connectivity between different regions, and show how the model can provide independent estimates of transfer rates between commonly used assessment regions. In particular, we find that retention rates in most assessment regions are considerably smaller (up to a factor of 2) than those estimated by this population of skipjack's primary assessment model. Moreover, these rates are sensitive to ocean state (e.g. El Nino vs La Nina) and so assuming fixed transfer rates between regions may lead to spurious stock estimates. A novel feature of the

  2. Satellite Animation Shows Movement and Landfall of Hurricane Nate

    NASA Image and Video Library

    2017-10-08

    This animation of NOAA's GOES East and West satellite imagery from Oct. 1 at 3:30 a.m. EDT (0730 UTC) to Oct 8 at 8 a.m. EDT (1200 UTC) shows the movement, development and landfall of Hurricane Nate at the mouth of the Mississippi River on Oct. 7 at 8 p.m. EDT.

  3. Optimal orientation in flows: providing a benchmark for animal movement strategies.

    PubMed

    McLaren, James D; Shamoun-Baranes, Judy; Dokter, Adriaan M; Klaassen, Raymond H G; Bouten, Willem

    2014-10-06

    Animal movements in air and water can be strongly affected by experienced flow. While various flow-orientation strategies have been proposed and observed, their performance in variable flow conditions remains unclear. We apply control theory to establish a benchmark for time-minimizing (optimal) orientation. We then define optimal orientation for movement in steady flow patterns and, using dynamic wind data, for short-distance mass movements of thrushes (Turdus sp.) and 6000 km non-stop migratory flights by great snipes, Gallinago media. Relative to the optimal benchmark, we assess the efficiency (travel speed) and reliability (success rate) of three generic orientation strategies: full compensation for lateral drift, vector orientation (single-heading movement) and goal orientation (continually heading towards the goal). Optimal orientation is characterized by detours to regions of high flow support, especially when flow speeds approach and exceed the animal's self-propelled speed. In strong predictable flow (short distance thrush flights), vector orientation adjusted to flow on departure is nearly optimal, whereas for unpredictable flow (inter-continental snipe flights), only goal orientation was near-optimally reliable and efficient. Optimal orientation provides a benchmark for assessing efficiency of responses to complex flow conditions, thereby offering insight into adaptive flow-orientation across taxa in the light of flow strength, predictability and navigation capacity.

  4. Optimal orientation in flows: providing a benchmark for animal movement strategies

    PubMed Central

    McLaren, James D.; Shamoun-Baranes, Judy; Dokter, Adriaan M.; Klaassen, Raymond H. G.; Bouten, Willem

    2014-01-01

    Animal movements in air and water can be strongly affected by experienced flow. While various flow-orientation strategies have been proposed and observed, their performance in variable flow conditions remains unclear. We apply control theory to establish a benchmark for time-minimizing (optimal) orientation. We then define optimal orientation for movement in steady flow patterns and, using dynamic wind data, for short-distance mass movements of thrushes (Turdus sp.) and 6000 km non-stop migratory flights by great snipes, Gallinago media. Relative to the optimal benchmark, we assess the efficiency (travel speed) and reliability (success rate) of three generic orientation strategies: full compensation for lateral drift, vector orientation (single-heading movement) and goal orientation (continually heading towards the goal). Optimal orientation is characterized by detours to regions of high flow support, especially when flow speeds approach and exceed the animal's self-propelled speed. In strong predictable flow (short distance thrush flights), vector orientation adjusted to flow on departure is nearly optimal, whereas for unpredictable flow (inter-continental snipe flights), only goal orientation was near-optimally reliable and efficient. Optimal orientation provides a benchmark for assessing efficiency of responses to complex flow conditions, thereby offering insight into adaptive flow-orientation across taxa in the light of flow strength, predictability and navigation capacity. PMID:25056213

  5. A new method for discovering behavior patterns among animal movements

    USGS Publications Warehouse

    Wang, Y.; Luo, Ze; Takekawa, John Y.; Prosser, Diann J.; Xiong, Y.; Newman, S.; Xiao, X.; Batbayar, N.; Spragens, Kyle A.; Balachandran, S.; Yan, B.

    2016-01-01

    Advanced satellite tracking technologies enable biologists to track animal movements at fine spatial and temporal scales. The resultant data present opportunities and challenges for understanding animal behavioral mechanisms. In this paper, we develop a new method to elucidate animal movement patterns from tracking data. Here, we propose the notion of continuous behavior patterns as a concise representation of popular migration routes and underlying sequential behaviors during migration. Each stage in the pattern is characterized in terms of space (i.e., the places traversed during movements) and time (i.e. the time spent in those places); that is, the behavioral state corresponding to a stage is inferred according to the spatiotemporal and sequential context. Hence, the pattern may be interpreted predictably. We develop a candidate generation and refinement framework to derive all continuous behavior patterns from raw trajectories. In the framework, we first define the representative spots to denote the underlying potential behavioral states that are extracted from individual trajectories according to the similarity of relaxed continuous locations in certain distinct time intervals. We determine the common behaviors of multiple individuals according to the spatiotemporal proximity of representative spots and apply a projection-based extension approach to generate candidate sequential behavior sequences as candidate patterns. Finally, the candidate generation procedure is combined with a refinement procedure to derive continuous behavior patterns. We apply an ordered processing strategy to accelerate candidate refinement. The proposed patterns and discovery framework are evaluated through conceptual experiments on both real GPS-tracking and large synthetic datasets.

  6. A new method for discovering behavior patterns among animal movements.

    PubMed

    Wang, Yuwei; Luo, Ze; Takekawa, John; Prosser, Diann; Xiong, Yan; Newman, Scott; Xiao, Xiangming; Batbayar, Nyambayar; Spragens, Kyle; Balachandran, Sivananinthaperumal; Yan, Baoping

    Advanced satellite tracking technologies enable biologists to track animal movements at fine spatial and temporal scales. The resultant data present opportunities and challenges for understanding animal behavioral mechanisms. In this paper, we develop a new method to elucidate animal movement patterns from tracking data. Here, we propose the notion of continuous behavior patterns as a concise representation of popular migration routes and underlying sequential behaviors during migration. Each stage in the pattern is characterized in terms of space (i.e., the places traversed during movements) and time (i.e. the time spent in those places); that is, the behavioral state corresponding to a stage is inferred according to the spatiotemporal and sequential context. Hence, the pattern may be interpreted predictably. We develop a candidate generation and refinement framework to derive all continuous behavior patterns from raw trajectories. In the framework, we first define the representative spots to denote the underlying potential behavioral states that are extracted from individual trajectories according to the similarity of relaxed continuous locations in certain distinct time intervals. We determine the common behaviors of multiple individuals according to the spatiotemporal proximity of representative spots and apply a projection-based extension approach to generate candidate sequential behavior sequences as candidate patterns. Finally, the candidate generation procedure is combined with a refinement procedure to derive continuous behavior patterns. We apply an ordered processing strategy to accelerate candidate refinement. The proposed patterns and discovery framework are evaluated through conceptual experiments on both real GPS-tracking and large synthetic datasets.

  7. A new method for discovering behavior patterns among animal movements

    PubMed Central

    Wang, Yuwei; Luo, Ze; Takekawa, John; Prosser, Diann; Xiong, Yan; Newman, Scott; Xiao, Xiangming; Batbayar, Nyambayar; Spragens, Kyle; Balachandran, Sivananinthaperumal; Yan, Baoping

    2016-01-01

    Advanced satellite tracking technologies enable biologists to track animal movements at fine spatial and temporal scales. The resultant data present opportunities and challenges for understanding animal behavioral mechanisms. In this paper, we develop a new method to elucidate animal movement patterns from tracking data. Here, we propose the notion of continuous behavior patterns as a concise representation of popular migration routes and underlying sequential behaviors during migration. Each stage in the pattern is characterized in terms of space (i.e., the places traversed during movements) and time (i.e. the time spent in those places); that is, the behavioral state corresponding to a stage is inferred according to the spatiotemporal and sequential context. Hence, the pattern may be interpreted predictably. We develop a candidate generation and refinement framework to derive all continuous behavior patterns from raw trajectories. In the framework, we first define the representative spots to denote the underlying potential behavioral states that are extracted from individual trajectories according to the similarity of relaxed continuous locations in certain distinct time intervals. We determine the common behaviors of multiple individuals according to the spatiotemporal proximity of representative spots and apply a projection-based extension approach to generate candidate sequential behavior sequences as candidate patterns. Finally, the candidate generation procedure is combined with a refinement procedure to derive continuous behavior patterns. We apply an ordered processing strategy to accelerate candidate refinement. The proposed patterns and discovery framework are evaluated through conceptual experiments on both real GPS-tracking and large synthetic datasets. PMID:27217810

  8. A random walk description of individual animal movement accounting for periods of rest

    NASA Astrophysics Data System (ADS)

    Tilles, Paulo F. C.; Petrovskii, Sergei V.; Natti, Paulo L.

    2016-11-01

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

  9. A random walk description of individual animal movement accounting for periods of rest.

    PubMed

    Tilles, Paulo F C; Petrovskii, Sergei V; Natti, Paulo L

    2016-11-01

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

  10. A random walk description of individual animal movement accounting for periods of rest

    PubMed Central

    Tilles, Paulo F. C.

    2016-01-01

    Animals do not move all the time but alternate the period of actual movement (foraging) with periods of rest (e.g. eating or sleeping). Although the existence of rest times is widely acknowledged in the literature and has even become a focus of increased attention recently, the theoretical approaches to describe animal movement by calculating the dispersal kernel and/or the mean squared displacement (MSD) rarely take rests into account. In this study, we aim to bridge this gap. We consider a composite stochastic process where the periods of active dispersal or ‘bouts’ (described by a certain baseline probability density function (pdf) of animal dispersal) alternate with periods of immobility. For this process, we derive a general equation that determines the pdf of this composite movement. The equation is analysed in detail in two special but important cases such as the standard Brownian motion described by a Gaussian kernel and the Levy flight described by a Cauchy distribution. For the Brownian motion, we show that in the large-time asymptotics the effect of rests results in a rescaling of the diffusion coefficient. The movement occurs as a subdiffusive transition between the two diffusive asymptotics. Interestingly, the Levy flight case shows similar properties, which indicates a certain universality of our findings. PMID:28018645

  11. 9 CFR 71.2 - Secretary to issue rule governing quarantine and interstate movement of diseased animals...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Secretary to issue rule governing quarantine and interstate movement of diseased animals, including poultry. 71.2 Section 71.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE...

  12. 9 CFR 71.2 - Secretary to issue rule governing quarantine and interstate movement of diseased animals...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Secretary to issue rule governing quarantine and interstate movement of diseased animals, including poultry. 71.2 Section 71.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE...

  13. 9 CFR 71.2 - Secretary to issue rule governing quarantine and interstate movement of diseased animals...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Secretary to issue rule governing quarantine and interstate movement of diseased animals, including poultry. 71.2 Section 71.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE...

  14. 9 CFR 71.2 - Secretary to issue rule governing quarantine and interstate movement of diseased animals...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Secretary to issue rule governing quarantine and interstate movement of diseased animals, including poultry. 71.2 Section 71.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE...

  15. Building an archive of Arctic-Boreal animal movements and links to remote sensing data

    NASA Astrophysics Data System (ADS)

    Bohrer, G.; Handler, M.; Davidson, S. C.; Boelman, N.

    2017-12-01

    Climate is changing in the Arctic and Boreal regions of North America more quickly than anywhere else on the planet. The impact of climate changes on wildlife in the region is difficult to assess, as they occur over decades, while wildlife monitoring programs have been in place for relatively short periods, have used a variety of data collection methods, and are not integrated across studies and governmental agencies. Further, linking wildlife movements to measures of weather and climate is impeded by the challenge of accessing environmental data products and differences in spatiotemporal scale. To analyze the impact of long-term changes in weather and habitat conditions on wildlife movements, we built an archive of avian, predator and ungulate movements throughout the Arctic-Boreal region. The archive is compiled and hosted in Movebank, a free, web-based service for managing animal movement data. Using Movebank allows us to securely manage data within a single database while supporting project-specific terms of use and access rights. By importing the data to the Movebank database, they are converted to a standard data format, reviewed for quality and completeness, and made easily accessible for analysis through the R package 'move'. In addition, the Env-DATA System in Movebank allows easy annotation of these and related time-location records with hundreds of environmental variables provided by global remote sensing and weather data products, including MODIS Land, Snow and Ice products, the ECMWF and NARR weather reanalyses, and others. The ABoVE Animal Movement Archive includes 6.6 million locations of over 3,000 animals collected by 50 programs and studies, contributed by over 25 collaborating institutions, with data extending from 1988 to the present. Organizing the data on Movebank has enabled collaboration and metaanalysis and has also improved their quality and completeness. The ABoVE Animal Movement Archive provides a platform actively used by data

  16. A hidden Markov model for reconstructing animal paths from solar geolocation loggers using templates for light intensity.

    PubMed

    Rakhimberdiev, Eldar; Winkler, David W; Bridge, Eli; Seavy, Nathaniel E; Sheldon, Daniel; Piersma, Theunis; Saveliev, Anatoly

    2015-01-01

    Solar archival tags (henceforth called geolocators) are tracking devices deployed on animals to reconstruct their long-distance movements on the basis of locations inferred post hoc with reference to the geographical and seasonal variations in the timing and speeds of sunrise and sunset. The increased use of geolocators has created a need for analytical tools to produce accurate and objective estimates of migration routes that are explicit in their uncertainty about the position estimates. We developed a hidden Markov chain model for the analysis of geolocator data. This model estimates tracks for animals with complex migratory behaviour by combining: (1) a shading-insensitive, template-fit physical model, (2) an uncorrelated random walk movement model that includes migratory and sedentary behavioural states, and (3) spatially explicit behavioural masks. The model is implemented in a specially developed open source R package FLightR. We used the particle filter (PF) algorithm to provide relatively fast model posterior computation. We illustrate our modelling approach with analysis of simulated data for stationary tags and of real tracks of both a tree swallow Tachycineta bicolor migrating along the east and a golden-crowned sparrow Zonotrichia atricapilla migrating along the west coast of North America. We provide a model that increases accuracy in analyses of noisy data and movements of animals with complicated migration behaviour. It provides posterior distributions for the positions of animals, their behavioural states (e.g., migrating or sedentary), and distance and direction of movement. Our approach allows biologists to estimate locations of animals with complex migratory behaviour based on raw light data. This model advances the current methods for estimating migration tracks from solar geolocation, and will benefit a fast-growing number of tracking studies with this technology.

  17. A generalised random encounter model for estimating animal density with remote sensor data.

    PubMed

    Lucas, Tim C D; Moorcroft, Elizabeth A; Freeman, Robin; Rowcliffe, J Marcus; Jones, Kate E

    2015-05-01

    Wildlife monitoring technology is advancing rapidly and the use of remote sensors such as camera traps and acoustic detectors is becoming common in both the terrestrial and marine environments. Current methods to estimate abundance or density require individual recognition of animals or knowing the distance of the animal from the sensor, which is often difficult. A method without these requirements, the random encounter model (REM), has been successfully applied to estimate animal densities from count data generated from camera traps. However, count data from acoustic detectors do not fit the assumptions of the REM due to the directionality of animal signals.We developed a generalised REM (gREM), to estimate absolute animal density from count data from both camera traps and acoustic detectors. We derived the gREM for different combinations of sensor detection widths and animal signal widths (a measure of directionality). We tested the accuracy and precision of this model using simulations of different combinations of sensor detection widths and animal signal widths, number of captures and models of animal movement.We find that the gREM produces accurate estimates of absolute animal density for all combinations of sensor detection widths and animal signal widths. However, larger sensor detection and animal signal widths were found to be more precise. While the model is accurate for all capture efforts tested, the precision of the estimate increases with the number of captures. We found no effect of different animal movement models on the accuracy and precision of the gREM.We conclude that the gREM provides an effective method to estimate absolute animal densities from remote sensor count data over a range of sensor and animal signal widths. The gREM is applicable for count data obtained in both marine and terrestrial environments, visually or acoustically (e.g. big cats, sharks, birds, echolocating bats and cetaceans). As sensors such as camera traps and acoustic

  18. Quantifying animal movement for caching foragers: the path identification index (PII) and cougars, Puma concolor

    USGS Publications Warehouse

    Ironside, Kirsten E.; Mattson, David J.; Theimer, Tad; Jansen, Brian; Holton, Brandon; Arundel, Terry; Peters, Michael; Sexton, Joseph O.; Edwards, Thomas C.

    2017-01-01

    Relocation studies of animal movement have focused on directed versus area restricted movement, which rely on correlations between step-length and turn angles, along with a degree of stationarity through time to define behavioral states. Although these approaches may work well for grazing foraging strategies in a patchy landscape, species that do not spend a significant amount of time searching out and gathering small dispersed food items, but instead feed for short periods on large, concentrated sources or cache food result in movements that maybe difficult to analyze using turning and velocity alone. We use GPS telemetry collected from a prey-caching predator, the cougar (Puma concolor), to test whether adding additional movement metrics capturing site recursion, to the more traditional velocity and turning, improve the ability to identify behaviors. We evaluated our movement index’s ability to identify behaviors using field investigations. We further tested for statistical stationarity across behaviors for use of topographic view-sheds. We found little correlation between turn angle, velocity, tortuosity, and site fidelity and combined them into a movement index used to identify movement paths (temporally autocorrelated movements) related to fast directed movements (taxis), area restricted movements (search), and prey caching (foraging). Changes in the frequency and duration of these movements were helpful for identifying seasonal activities such as migration and denning in females. Comparison of field investigations of cougar activities to behavioral classes defined using the movement index and found an overall classification accuracy of 81%. Changes in behaviors resulted in changes in how cougars used topographic view-sheds, showing statistical non-stationarity over time. The movement index shows promise for identifying behaviors in species that frequently return to specific locations such as food caches, watering holes, or dens, and highlights the role

  19. Applying network theory to animal movements to identify properties of landscape space use.

    PubMed

    Bastille-Rousseau, Guillaume; Douglas-Hamilton, Iain; Blake, Stephen; Northrup, Joseph M; Wittemyer, George

    2018-04-01

    Network (graph) theory is a popular analytical framework to characterize the structure and dynamics among discrete objects and is particularly effective at identifying critical hubs and patterns of connectivity. The identification of such attributes is a fundamental objective of animal movement research, yet network theory has rarely been applied directly to animal relocation data. We develop an approach that allows the analysis of movement data using network theory by defining occupied pixels as nodes and connection among these pixels as edges. We first quantify node-level (local) metrics and graph-level (system) metrics on simulated movement trajectories to assess the ability of these metrics to pull out known properties in movement paths. We then apply our framework to empirical data from African elephants (Loxodonta africana), giant Galapagos tortoises (Chelonoidis spp.), and mule deer (Odocoileous hemionus). Our results indicate that certain node-level metrics, namely degree, weight, and betweenness, perform well in capturing local patterns of space use, such as the definition of core areas and paths used for inter-patch movement. These metrics were generally applicable across data sets, indicating their robustness to assumptions structuring analysis or strategies of movement. Other metrics capture local patterns effectively, but were sensitive to specified graph properties, indicating case specific applications. Our analysis indicates that graph-level metrics are unlikely to outperform other approaches for the categorization of general movement strategies (central place foraging, migration, nomadism). By identifying critical nodes, our approach provides a robust quantitative framework to identify local properties of space use that can be used to evaluate the effect of the loss of specific nodes on range wide connectivity. Our network approach is intuitive, and can be implemented across imperfectly sampled or large-scale data sets efficiently, providing a

  20. Homogenization of Large-Scale Movement Models in Ecology

    USGS Publications Warehouse

    Garlick, M.J.; Powell, J.A.; Hooten, M.B.; McFarlane, L.R.

    2011-01-01

    A difficulty in using diffusion models to predict large scale animal population dispersal is that individuals move differently based on local information (as opposed to gradients) in differing habitat types. This can be accommodated by using ecological diffusion. However, real environments are often spatially complex, limiting application of a direct approach. Homogenization for partial differential equations has long been applied to Fickian diffusion (in which average individual movement is organized along gradients of habitat and population density). We derive a homogenization procedure for ecological diffusion and apply it to a simple model for chronic wasting disease in mule deer. Homogenization allows us to determine the impact of small scale (10-100 m) habitat variability on large scale (10-100 km) movement. The procedure generates asymptotic equations for solutions on the large scale with parameters defined by small-scale variation. The simplicity of this homogenization procedure is striking when compared to the multi-dimensional homogenization procedure for Fickian diffusion,and the method will be equally straightforward for more complex models. ?? 2010 Society for Mathematical Biology.

  1. Optimizing surveillance for livestock disease spreading through animal movements

    PubMed Central

    Bajardi, Paolo; Barrat, Alain; Savini, Lara; Colizza, Vittoria

    2012-01-01

    The spatial propagation of many livestock infectious diseases critically depends on the animal movements among premises; so the knowledge of movement data may help us to detect, manage and control an outbreak. The identification of robust spreading features of the system is however hampered by the temporal dimension characterizing population interactions through movements. Traditional centrality measures do not provide relevant information as results strongly fluctuate in time and outbreak properties heavily depend on geotemporal initial conditions. By focusing on the case study of cattle displacements in Italy, we aim at characterizing livestock epidemics in terms of robust features useful for planning and control, to deal with temporal fluctuations, sensitivity to initial conditions and missing information during an outbreak. Through spatial disease simulations, we detect spreading paths that are stable across different initial conditions, allowing the clustering of the seeds and reducing the epidemic variability. Paths also allow us to identify premises, called sentinels, having a large probability of being infected and providing critical information on the outbreak origin, as encoded in the clusters. This novel procedure provides a general framework that can be applied to specific diseases, for aiding risk assessment analysis and informing the design of optimal surveillance systems. PMID:22728387

  2. Low relative error in consumer-grade GPS units make them ideal for measuring small-scale animal movement patterns

    PubMed Central

    Severns, Paul M.

    2015-01-01

    Consumer-grade GPS units are a staple of modern field ecology, but the relatively large error radii reported by manufacturers (up to 10 m) ostensibly precludes their utility in measuring fine-scale movement of small animals such as insects. Here we demonstrate that for data collected at fine spatio-temporal scales, these devices can produce exceptionally accurate data on step-length and movement patterns of small animals. With an understanding of the properties of GPS error and how it arises, it is possible, using a simple field protocol, to use consumer grade GPS units to collect step-length data for the movement of small animals that introduces a median error as small as 11 cm. These small error rates were measured in controlled observations of real butterfly movement. Similar conclusions were reached using a ground-truth test track prepared with a field tape and compass and subsequently measured 20 times using the same methodology as the butterfly tracking. Median error in the ground-truth track was slightly higher than the field data, mostly between 20 and 30 cm, but even for the smallest ground-truth step (70 cm), this is still a signal-to-noise ratio of 3:1, and for steps of 3 m or more, the ratio is greater than 10:1. Such small errors relative to the movements being measured make these inexpensive units useful for measuring insect and other small animal movements on small to intermediate scales with budgets orders of magnitude lower than survey-grade units used in past studies. As an additional advantage, these units are simpler to operate, and insect or other small animal trackways can be collected more quickly than either survey-grade units or more traditional ruler/gird approaches. PMID:26312190

  3. Low relative error in consumer-grade GPS units make them ideal for measuring small-scale animal movement patterns.

    PubMed

    Breed, Greg A; Severns, Paul M

    2015-01-01

    Consumer-grade GPS units are a staple of modern field ecology, but the relatively large error radii reported by manufacturers (up to 10 m) ostensibly precludes their utility in measuring fine-scale movement of small animals such as insects. Here we demonstrate that for data collected at fine spatio-temporal scales, these devices can produce exceptionally accurate data on step-length and movement patterns of small animals. With an understanding of the properties of GPS error and how it arises, it is possible, using a simple field protocol, to use consumer grade GPS units to collect step-length data for the movement of small animals that introduces a median error as small as 11 cm. These small error rates were measured in controlled observations of real butterfly movement. Similar conclusions were reached using a ground-truth test track prepared with a field tape and compass and subsequently measured 20 times using the same methodology as the butterfly tracking. Median error in the ground-truth track was slightly higher than the field data, mostly between 20 and 30 cm, but even for the smallest ground-truth step (70 cm), this is still a signal-to-noise ratio of 3:1, and for steps of 3 m or more, the ratio is greater than 10:1. Such small errors relative to the movements being measured make these inexpensive units useful for measuring insect and other small animal movements on small to intermediate scales with budgets orders of magnitude lower than survey-grade units used in past studies. As an additional advantage, these units are simpler to operate, and insect or other small animal trackways can be collected more quickly than either survey-grade units or more traditional ruler/gird approaches.

  4. A likelihood-based biostatistical model for analyzing consumer movement in simultaneous choice experiments

    USDA-ARS?s Scientific Manuscript database

    Measures of animal movement versus consumption rates can provide valuable, ecologically relevant information on feeding preference, specifically estimates of attraction rate, leaving rate, tenure time, or measures of flight/walking path. Here, we develop a simple biostatistical model to analyze repe...

  5. Movement to curtail animal dissections in zoology curriculum: review of the Indian experience.

    PubMed

    Akbarsha, Mohammad Abdulkader

    2007-01-01

    Animal dissections have been dropped from the curriculum in several developed countries, and virtual laboratories are taking their place, or at least the concept of the "three R's" is becoming accepted. Yet, the scenario in the developing countries in this regard has been dismal. However, recently, a movement has started in India in this area, thanks to the aggressive approach of PfA, I-CARE and InterNICHE, supported by a few zoology educators and policy makers, who joined this movement as freelancers. The aggressive campaigners against animal dissections put up convincing arguments to the orthodox zoology educators and higher education planners with such veracity that the arguments cannot be ignored. The arguments, to be presented in detail at the conference, and the campaign have been rewarded with success such that a few universities and autonomous colleges have revamped their zoology curricula so as to dispense with or reduce animal dissections. The Bharathidasan University, Tiruchirappalli, Tamil Nadu, India, has been the trendsetter, evolving what is known as the "Bharathidasan University Model". A memorandum from I-CARE and PfA to the University Grants Commission, Government of India, New Delhi, was sent out by the UGC to the universities with a request to consider the points positively. However, there is still a need to bring about an attitudinal change in the zoology educators and higher education planners such that they participate willingly in this endeavour. The role-players at all levels are identified and approached with a language that is understandable to each and are adequately supported by hands-on training in the alternative methods. Ultimately, the responsibility in this regard lies with the educators themselves, since they are the ones who, working in the academic committees that design the curricula, can cut down on the requirement for dissections.

  6. Plasma iron levels appraised 15 days after spinal cord injury in a limb movement animal model.

    PubMed

    Reis, F M; Esteves, A M; Tufik, S; de Mello, M T

    2011-03-01

    Experimental, controlled trial. The purpose of this study was to evaluate plasma iron and transferrin levels in a limb movement animal model with spinal cord injury (SCI). Universidade Federal de São Paulo, Departamento de Psicobiologia. In all, 72 male Wistar rats aged 90 days were divided into four groups: (1) acute SCI (1 day, SCI1), (2) 3 days post-SCI (SCI3), (3) 7 days post-SCI (SCI7) and (4) 15 days post-SCI (SCI15). Each of these groups had corresponding control (CTRL) and SHAM groups. Plasma iron and transferrin levels of the different groups were analyzed using a one-way analysis of variance (ANOVA) followed by Tukey's test. We found a significant reduction in iron plasma levels after SCI compared with the CTRL group: SCI1 (CTRL: 175±10.58 μg dl(-1); SCI: 108.28±11.7 μg dl(-1)), SCI3 (CTRL: 195.5±11.00 μg dl(-1); SCI: 127.88±12.63 μg dl(-1)), SCI7 (CTRL: 186±2.97 μg dl(-1); SCI: 89.2±15.39 μg dl(-1)) and SCI15 (CTRL: 163±5.48 μg dl(-1); SCI: 124.44±10.30 μg dl(-1)) (P<0.05; ANOVA). The SHAM1 group demonstrated a reduction in iron plasma after acute SCI (CTRL: 175±10.58 μg dl(-1); SHAM: 114.60±7.81 μg dl(-1)) (P<0.05; ANOVA). Reduced iron metabolism after SCI may be one of the mechanisms involved in the pathogenesis of sleep-related movement disorders.

  7. Uncertainty in spatially explicit animal dispersal models

    USGS Publications Warehouse

    Mooij, Wolf M.; DeAngelis, Donald L.

    2003-01-01

    Uncertainty in estimates of survival of dispersing animals is a vexing difficulty in conservation biology. The current notion is that this uncertainty decreases the usefulness of spatially explicit population models in particular. We examined this problem by comparing dispersal models of three levels of complexity: (1) an event-based binomial model that considers only the occurrence of mortality or arrival, (2) a temporally explicit exponential model that employs mortality and arrival rates, and (3) a spatially explicit grid-walk model that simulates the movement of animals through an artificial landscape. Each model was fitted to the same set of field data. A first objective of the paper is to illustrate how the maximum-likelihood method can be used in all three cases to estimate the means and confidence limits for the relevant model parameters, given a particular set of data on dispersal survival. Using this framework we show that the structure of the uncertainty for all three models is strikingly similar. In fact, the results of our unified approach imply that spatially explicit dispersal models, which take advantage of information on landscape details, suffer less from uncertainly than do simpler models. Moreover, we show that the proposed strategy of model development safeguards one from error propagation in these more complex models. Finally, our approach shows that all models related to animal dispersal, ranging from simple to complex, can be related in a hierarchical fashion, so that the various approaches to modeling such dispersal can be viewed from a unified perspective.

  8. Robustness of movement models: can models bridge the gap between temporal scales of data sets and behavioural processes?

    PubMed

    Schlägel, Ulrike E; Lewis, Mark A

    2016-12-01

    Discrete-time random walks and their extensions are common tools for analyzing animal movement data. In these analyses, resolution of temporal discretization is a critical feature. Ideally, a model both mirrors the relevant temporal scale of the biological process of interest and matches the data sampling rate. Challenges arise when resolution of data is too coarse due to technological constraints, or when we wish to extrapolate results or compare results obtained from data with different resolutions. Drawing loosely on the concept of robustness in statistics, we propose a rigorous mathematical framework for studying movement models' robustness against changes in temporal resolution. In this framework, we define varying levels of robustness as formal model properties, focusing on random walk models with spatially-explicit component. With the new framework, we can investigate whether models can validly be applied to data across varying temporal resolutions and how we can account for these different resolutions in statistical inference results. We apply the new framework to movement-based resource selection models, demonstrating both analytical and numerical calculations, as well as a Monte Carlo simulation approach. While exact robustness is rare, the concept of approximate robustness provides a promising new direction for analyzing movement models.

  9. A Guide to Neurotoxic Animal Models of Parkinson’s Disease

    PubMed Central

    Tieu, Kim

    2011-01-01

    Parkinson’s disease (PD) is a neurological movement disorder primarily resulting from damage to the nigrostriatal dopaminergic pathway. To elucidate the pathogenesis, mechanisms of cell death, and to evaluate therapeutic strategies for PD, numerous animal models have been developed. Understanding the strengths and limitations of these models can significantly impact the choice of model, experimental design, and data interpretation. The primary objectives of this article are twofold: First, to assist new investigators who are contemplating embarking on PD research to navigate through the available animal models. Emphasis will be placed on common neurotoxic murine models in which toxic molecules are used to lesion the nigrostriatal dopaminergic system. And second, to provide an overview of basic technical requirements for assessing the pathology, structure, and function of the nigrostriatal pathway. PMID:22229125

  10. Implications of movement for species distribution models - Rethinking environmental data tools.

    PubMed

    Bruneel, Stijn; Gobeyn, Sacha; Verhelst, Pieterjan; Reubens, Jan; Moens, Tom; Goethals, Peter

    2018-07-01

    Movement is considered an essential process in shaping the distributions of species. Nevertheless, most species distribution models (SDMs) still focus solely on environment-species relationships to predict the occurrence of species. Furthermore, the currently used indirect estimates of movement allow to assess habitat accessibility, but do not provide an accurate description of movement. Better proxies of movement are needed to assess the dispersal potential of individual species and to gain a more practical insight in the interconnectivity of communities. Telemetry techniques are rapidly evolving and highly capable to provide explicit descriptions of movement, but their usefulness for SDMs will mainly depend on the ability of these models to deal with hitherto unconsidered ecological processes. More specifically, the integration of movement is likely to affect the environmental data requirements as the connection between environmental and biological data is crucial to provide reliable results. Mobility implies the occupancy of a continuum of space, hence an adequate representation of both geographical and environmental space is paramount to study mobile species distributions. In this context, environmental models, remote sensing techniques and animal-borne environmental sensors are discussed as potential techniques to obtain suitable environmental data. In order to provide an in-depth review of the aforementioned methods, we have chosen to use the modelling of fish distributions as a case study. The high mobility of fish and the often highly variable nature of the aquatic environment generally complicate model development, making it an adequate subject for research. Furthermore, insight into the distribution of fish is of great interest for fish stock assessments and water management worldwide, underlining its practical relevance. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Use, misuse and extensions of "ideal gas" models of animal encounter.

    PubMed

    Hutchinson, John M C; Waser, Peter M

    2007-08-01

    Biologists have repeatedly rediscovered classical models from physics predicting collision rates in an ideal gas. These models, and their two-dimensional analogues, have been used to predict rates and durations of encounters among animals or social groups that move randomly and independently, given population density, velocity, and distance at which an encounter occurs. They have helped to separate cases of mixed-species association based on behavioural attraction from those that simply reflect high population densities, and to detect cases of attraction or avoidance among conspecifics. They have been used to estimate the impact of population density, speeds of movement and size on rates of encounter between members of the opposite sex, between gametes, between predators and prey, and between observers and the individuals that they are counting. One limitation of published models has been that they predict rates of encounter, but give no means of determining whether observations differ significantly from predictions. Another uncertainty is the robustness of the predictions when animal movements deviate from the model's assumptions in specific, biologically relevant ways. Here, we review applications of the ideal gas model, derive extensions of the model to cover some more realistic movement patterns, correct several errors that have arisen in the literature, and show how to generate confidence limits for expected rates of encounter among independently moving individuals. We illustrate these results using data from mangabey monkeys originally used along with the ideal gas model to argue that groups avoid each other. Although agent-based simulations provide a more flexible alternative approach, the ideal gas model remains both a valuable null model and a useful, less onerous, approximation to biological reality.

  12. Impact of Bisphosphonate on Orthodontic tooth movement and osteoclastic count: An Animal Study

    PubMed Central

    Venkataramana, V; Chidambaram, S; Reddy, B Vishnuvardhan; Goud, E V Soma Shekara; Arafath, Mohammed; Krishnan, Santhana

    2014-01-01

    Background : The aim of the current study is to examine the effect of systemically administered BP-Pamidronate, on Orthodontic Tooth Movement (OTM) along with osteoclastic quantification in New Zealand white rabbits. Materials & Methods : Twenty rabbits used in the study, were equally divided into 2 groups ; Group-1 as Control & Group-2 as Experimental. A sentalloy NITI closed coil spring (GAC International, USA) of 100 gram force, ligated between the lower first molar and the anterior most incisors of the rabbit has served as orthodontic force element. The BP- Pamidronate was administered at the dosage of 1.5 mg/kg body intra-peritonially, on the 1st, 7th and 14th day of the experiment. On the 21st day both group of animals were sacrificed, mandibles were dissected. The formed diastema between the 1st and 2nd molar was measured on the dissected mandibles using standard metric scale, which is considered as the OTM in the mesial direction. Next, the alveolar bone regions along with intact mesial surfaces were processed for histological investigation (osteoclastic count). Results : The student ‘t’ test has been done to compare the mean values of molar tooth movement and osteoclastic count. Parameter :1 molar tooth movement has shown a significant difference between the control (3.750 ± 0.548 mm) and the experimental group (3.050 ± 0.556 mm) with calculated ‘p’ value (p-value <0.05) is significant at 0.0110 level. Parameter : 2 osteoclastic count has shown a significant difference between the control (13.335000 ± 0.735856 per square mm.) and the experimental group (11.426900 ± 1.49369 per square mm) calculated ‘p’ value (p-value <0.05) is significant at 0.003 level. Conclusion : The molar tooth movement and the osteoclastic count were significantly reduced in BP – Pamidronate administered animals than non-drug recipients. How to cite the article: Venkataramana V, Chidambaram S, Reddy BV, Goud EV, Arafath M, Krishnan S. Impact of Bisphosphonate on

  13. Impact of Bisphosphonate on Orthodontic tooth movement and osteoclastic count: An Animal Study.

    PubMed

    Venkataramana, V; Chidambaram, S; Reddy, B Vishnuvardhan; Goud, E V Soma Shekara; Arafath, Mohammed; Krishnan6, Santhana

    2014-04-01

    Background : The aim of the current study is to examine the effect of systemically administered BP-Pamidronate, on Orthodontic Tooth Movement (OTM) along with osteoclastic quantification in New Zealand white rabbits. Materials & Methods : Twenty rabbits used in the study, were equally divided into 2 groups ; Group-1 as Control & Group-2 as Experimental. A sentalloy NITI closed coil spring (GAC International, USA) of 100 gram force, ligated between the lower first molar and the anterior most incisors of the rabbit has served as orthodontic force element. The BP- Pamidronate was administered at the dosage of 1.5 mg/kg body intra-peritonially, on the 1st, 7th and 14th day of the experiment. On the 21st day both group of animals were sacrificed, mandibles were dissected. The formed diastema between the 1st and 2nd molar was measured on the dissected mandibles using standard metric scale, which is considered as the OTM in the mesial direction. Next, the alveolar bone regions along with intact mesial surfaces were processed for histological investigation (osteoclastic count). Results : The student 't' test has been done to compare the mean values of molar tooth movement and osteoclastic count. Parameter :1 molar tooth movement has shown a significant difference between the control (3.750 ± 0.548 mm) and the experimental group (3.050 ± 0.556 mm) with calculated 'p' value (p-value <0.05) is significant at 0.0110 level. Parameter : 2 osteoclastic count has shown a significant difference between the control (13.335000 ± 0.735856 per square mm.) and the experimental group (11.426900 ± 1.49369 per square mm) calculated 'p' value (p-value <0.05) is significant at 0.003 level. Conclusion : The molar tooth movement and the osteoclastic count were significantly reduced in BP - Pamidronate administered animals than non-drug recipients. How to cite the article: Venkataramana V, Chidambaram S, Reddy BV, Goud EV, Arafath M, Krishnan S. Impact of Bisphosphonate on Orthodontic tooth

  14. Effects of Number of Animals Monitored on Representations of Cattle Group Movement Characteristics and Spatial Occupancy

    PubMed Central

    Liu, Tong; Green, Angela R.; Rodríguez, Luis F.; Ramirez, Brett C.; Shike, Daniel W.

    2015-01-01

    The number of animals required to represent the collective characteristics of a group remains a concern in animal movement monitoring with GPS. Monitoring a subset of animals from a group instead of all animals can reduce costs and labor; however, incomplete data may cause information losses and inaccuracy in subsequent data analyses. In cattle studies, little work has been conducted to determine the number of cattle within a group needed to be instrumented considering subsequent analyses. Two different groups of cattle (a mixed group of 24 beef cows and heifers, and another group of 8 beef cows) were monitored with GPS collars at 4 min intervals on intensively managed pastures and corn residue fields in 2011. The effects of subset group size on cattle movement characterization and spatial occupancy analysis were evaluated by comparing the results between subset groups and the entire group for a variety of summarization parameters. As expected, more animals yield better results for all parameters. Results show the average group travel speed and daily travel distances are overestimated as subset group size decreases, while the average group radius is underestimated. Accuracy of group centroid locations and group radii are improved linearly as subset group size increases. A kernel density estimation was performed to quantify the spatial occupancy by cattle via GPS location data. Results show animals among the group had high similarity of spatial occupancy. Decisions regarding choosing an appropriate subset group size for monitoring depend on the specific use of data for subsequent analysis: a small subset group may be adequate for identifying areas visited by cattle; larger subset group size (e.g. subset group containing more than 75% of animals) is recommended to achieve better accuracy of group movement characteristics and spatial occupancy for the use of correlating cattle locations with other environmental factors. PMID:25647571

  15. Modelling gait transition in two-legged animals

    NASA Astrophysics Data System (ADS)

    Pinto, Carla M. A.; Santos, Alexandra P.

    2011-12-01

    The study of locomotor patterns has been a major research goal in the last decades. Understanding how intralimb and interlimb coordination works out so well in animals' locomotion is a hard and challenging task. Many models have been proposed to model animal's rhythms. These models have also been applied to the control of rhythmic movements of adaptive legged robots, namely biped, quadruped and other designs. In this paper we study gait transition in a central pattern generator (CPG) model for bipeds, the 4-cells model. This model is proposed by Golubitsky, Stewart, Buono and Collins and is studied further by Pinto and Golubitsky. We briefly resume the work done by Pinto and Golubitsky. We compute numerically gait transition in the 4-cells CPG model for bipeds. We use Morris-Lecar equations and Wilson-Cowan equations as the internal dynamics for each cell. We also consider two types of coupling between the cells: diffusive and synaptic. We obtain secondary gaits by bifurcation of primary gaits, by varying the coupling strengths. Nevertheless, some bifurcating branches could not be obtained, emphasizing the fact that despite analytically those bifurcations exist, finding them is a hard task and requires variation of other parameters of the equations. We note that the type of coupling did not influence the results.

  16. The mathematics of movement

    USGS Publications Warehouse

    Johnson, D.H.

    1999-01-01

    Review of: Quantitative Analysis of Movement: Measuring and Modeling Population Redistribution in Animals and Plants. Peter Turchin. 1998. Sinauer Associates, Sunderland, MA. 306 pages. $38.95 (paper).

  17. A Physics-Inspired Mechanistic Model of Migratory Movement Patterns in Birds.

    PubMed

    Revell, Christopher; Somveille, Marius

    2017-08-29

    In this paper, we introduce a mechanistic model of migratory movement patterns in birds, inspired by ideas and methods from physics. Previous studies have shed light on the factors influencing bird migration but have mainly relied on statistical correlative analysis of tracking data. Our novel method offers a bottom up explanation of population-level migratory movement patterns. It differs from previous mechanistic models of animal migration and enables predictions of pathways and destinations from a given starting location. We define an environmental potential landscape from environmental data and simulate bird movement within this landscape based on simple decision rules drawn from statistical mechanics. We explore the capacity of the model by qualitatively comparing simulation results to the non-breeding migration patterns of a seabird species, the Black-browed Albatross (Thalassarche melanophris). This minimal, two-parameter model was able to capture remarkably well the previously documented migration patterns of the Black-browed Albatross, with the best combination of parameter values conserved across multiple geographically separate populations. Our physics-inspired mechanistic model could be applied to other bird and highly-mobile species, improving our understanding of the relative importance of various factors driving migration and making predictions that could be useful for conservation.

  18. A Model of Loggerhead Sea Turtle (Caretta caretta) Habitat and Movement in the Oceanic North Pacific

    PubMed Central

    Abecassis, Melanie; Senina, Inna; Lehodey, Patrick; Gaspar, Philippe; Parker, Denise; Balazs, George; Polovina, Jeffrey

    2013-01-01

    Habitat preferences for juvenile loggerhead turtles in the North Pacific were investigated with data from two several-year long tagging programs, using 224 satellite transmitters deployed on wild and captive-reared turtles. Animals ranged between 23 and 81 cm in straight carapace length. Tracks were used to investigate changes in temperature preferences and speed of the animals with size. Average sea surface temperatures along the tracks ranged from 18 to 23 °C. Bigger turtles generally experienced larger temperature ranges and were encountered in warmer surface waters. Seasonal differences between small and big turtles suggest that the larger ones dive deeper than the mixed layer and subsequently target warmer surface waters to rewarm. Average swimming speeds were under 1 km/h and increased with size for turtles bigger than 30 cm. However, when expressed in body lengths per second (bl s−1), smaller turtles showed much higher swimming speeds (>1 bl s −1) than bigger ones (0.5 bl s−1). Temperature and speed values at size estimated from the tracks were used to parameterize a habitat-based Eulerian model to predict areas of highest probability of presence in the North Pacific. The model-generated habitat index generally matched the tracks closely, capturing the north-south movements of tracked animals, but the model failed to replicate observed east-west movements, suggesting temperature and foraging preferences are not the only factors driving large-scale loggerhead movements. Model outputs could inform potential bycatch reduction strategies. PMID:24039901

  19. Minimally Invasive Techniques to Accelerate the Orthodontic Tooth Movement: A Systematic Review of Animal Studies

    PubMed Central

    Qamruddin, Irfan; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli; Husein, Adam

    2015-01-01

    Objective. To evaluate various noninvasive and minimally invasive procedures for the enhancement of orthodontic tooth movement in animals. Materials and Methods. Literature was searched using NCBI (PubMed, PubMed Central, and PubMed Health), MedPilot (Medline, Catalogue ZB MED, Catalogue Medicine Health, and Excerpta Medica Database (EMBASE)), and Google Scholar from January 2009 till 31 December 2014. We included original articles related to noninvasive and minimally invasive procedures to enhance orthodontic tooth movement in animals. Extraction of data and quality assessments were carried out by two observers independently. Results. The total number of hits was 9195 out of which just 11 fulfilled the inclusion criteria. Nine articles were good and 5 articles were moderate in quality. Low level laser therapy (LLLT) was among the most common noninvasive techniques whereas flapless corticision using various instruments was among the commonest minimally invasive procedures to enhance velocity of tooth movement. Conclusions. LLLT, low intensity pulsed ultrasound (LIPUS), mechanical vibration, and flapless corticision are emerging noninvasive and minimally invasive techniques which need further researches to establish protocols to use them clinically with conviction. PMID:26881201

  20. A Sensory-Motor Control Model of Animal Flight Explains Why Bats Fly Differently in Light Versus Dark

    PubMed Central

    Bar, Nadav S.; Skogestad, Sigurd; Marçal, Jose M.; Ulanovsky, Nachum; Yovel, Yossi

    2015-01-01

    Animal flight requires fine motor control. However, it is unknown how flying animals rapidly transform noisy sensory information into adequate motor commands. Here we developed a sensorimotor control model that explains vertebrate flight guidance with high fidelity. This simple model accurately reconstructed complex trajectories of bats flying in the dark. The model implies that in order to apply appropriate motor commands, bats have to estimate not only the angle-to-target, as was previously assumed, but also the angular velocity (“proportional-derivative” controller). Next, we conducted experiments in which bats flew in light conditions. When using vision, bats altered their movements, reducing the flight curvature. This change was explained by the model via reduction in sensory noise under vision versus pure echolocation. These results imply a surprising link between sensory noise and movement dynamics. We propose that this sensory-motor link is fundamental to motion control in rapidly moving animals under different sensory conditions, on land, sea, or air. PMID:25629809

  1. Energy efficiency and allometry of movement of swimming and flying animals.

    PubMed

    Bale, Rahul; Hao, Max; Bhalla, Amneet Pal Singh; Patankar, Neelesh A

    2014-05-27

    Which animals use their energy better during movement? One metric to answer this question is the energy cost per unit distance per unit weight. Prior data show that this metric decreases with mass, which is considered to imply that massive animals are more efficient. Although useful, this metric also implies that two dynamically equivalent animals of different sizes will not be considered equally efficient. We resolve this longstanding issue by first determining the scaling of energy cost per unit distance traveled. The scale is found to be M(2/3) or M(1/2), where M is the animal mass. Second, we introduce an energy-consumption coefficient (CE) defined as energy per unit distance traveled divided by this scale. CE is a measure of efficiency of swimming and flying, analogous to how drag coefficient quantifies aerodynamic drag on vehicles. Derivation of the energy-cost scale reveals that the assumption that undulatory swimmers spend energy to overcome drag in the direction of swimming is inappropriate. We derive allometric scalings that capture trends in data of swimming and flying animals over 10-20 orders of magnitude by mass. The energy-consumption coefficient reveals that swimmers beyond a critical mass, and most fliers are almost equally efficient as if they are dynamically equivalent; increasingly massive animals are not more efficient according to the proposed metric. Distinct allometric scalings are discovered for large and small swimmers. Flying animals are found to require relatively more energy compared with swimmers.

  2. Energy efficiency and allometry of movement of swimming and flying animals

    PubMed Central

    Bale, Rahul; Hao, Max; Bhalla, Amneet Pal Singh; Patankar, Neelesh A.

    2014-01-01

    Which animals use their energy better during movement? One metric to answer this question is the energy cost per unit distance per unit weight. Prior data show that this metric decreases with mass, which is considered to imply that massive animals are more efficient. Although useful, this metric also implies that two dynamically equivalent animals of different sizes will not be considered equally efficient. We resolve this longstanding issue by first determining the scaling of energy cost per unit distance traveled. The scale is found to be M2/3 or M1/2, where M is the animal mass. Second, we introduce an energy-consumption coefficient (CE) defined as energy per unit distance traveled divided by this scale. CE is a measure of efficiency of swimming and flying, analogous to how drag coefficient quantifies aerodynamic drag on vehicles. Derivation of the energy-cost scale reveals that the assumption that undulatory swimmers spend energy to overcome drag in the direction of swimming is inappropriate. We derive allometric scalings that capture trends in data of swimming and flying animals over 10–20 orders of magnitude by mass. The energy-consumption coefficient reveals that swimmers beyond a critical mass, and most fliers are almost equally efficient as if they are dynamically equivalent; increasingly massive animals are not more efficient according to the proposed metric. Distinct allometric scalings are discovered for large and small swimmers. Flying animals are found to require relatively more energy compared with swimmers. PMID:24821764

  3. The Effect of Map Boundary on Estimates of Landscape Resistance to Animal Movement

    PubMed Central

    Koen, Erin L.; Garroway, Colin J.; Wilson, Paul J.; Bowman, Jeff

    2010-01-01

    Background Artificial boundaries on a map occur when the map extent does not cover the entire area of study; edges on the map do not exist on the ground. These artificial boundaries might bias the results of animal dispersal models by creating artificial barriers to movement for model organisms where there are no barriers for real organisms. Here, we characterize the effects of artificial boundaries on calculations of landscape resistance to movement using circuit theory. We then propose and test a solution to artificially inflated resistance values whereby we place a buffer around the artificial boundary as a substitute for the true, but unknown, habitat. Methodology/Principal Findings We randomly assigned landscape resistance values to map cells in the buffer in proportion to their occurrence in the known map area. We used circuit theory to estimate landscape resistance to organism movement and gene flow, and compared the output across several scenarios: a habitat-quality map with artificial boundaries and no buffer, a map with a buffer composed of randomized habitat quality data, and a map with a buffer composed of the true habitat quality data. We tested the sensitivity of the randomized buffer to the possibility that the composition of the real but unknown buffer is biased toward high or low quality. We found that artificial boundaries result in an overestimate of landscape resistance. Conclusions/Significance Artificial map boundaries overestimate resistance values. We recommend the use of a buffer composed of randomized habitat data as a solution to this problem. We found that resistance estimated using the randomized buffer did not differ from estimates using the real data, even when the composition of the real data was varied. Our results may be relevant to those interested in employing Circuitscape software in landscape connectivity and landscape genetics studies. PMID:20668690

  4. 9 CFR 71.17 - Interstate movement of dead poultry or other animals prohibited in same car with live poultry or...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement of dead poultry or other animals prohibited in same car with live poultry or other animals. 71.17 Section 71.17 Animals and... of dead poultry or other animals prohibited in same car with live poultry or other animals. No dead...

  5. 9 CFR 71.17 - Interstate movement of dead poultry or other animals prohibited in same car with live poultry or...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Interstate movement of dead poultry or other animals prohibited in same car with live poultry or other animals. 71.17 Section 71.17 Animals and... of dead poultry or other animals prohibited in same car with live poultry or other animals. No dead...

  6. 9 CFR 71.17 - Interstate movement of dead poultry or other animals prohibited in same car with live poultry or...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Interstate movement of dead poultry or other animals prohibited in same car with live poultry or other animals. 71.17 Section 71.17 Animals and... of dead poultry or other animals prohibited in same car with live poultry or other animals. No dead...

  7. 9 CFR 71.17 - Interstate movement of dead poultry or other animals prohibited in same car with live poultry or...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Interstate movement of dead poultry or other animals prohibited in same car with live poultry or other animals. 71.17 Section 71.17 Animals and... of dead poultry or other animals prohibited in same car with live poultry or other animals. No dead...

  8. 9 CFR 71.17 - Interstate movement of dead poultry or other animals prohibited in same car with live poultry or...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Interstate movement of dead poultry or other animals prohibited in same car with live poultry or other animals. 71.17 Section 71.17 Animals and... of dead poultry or other animals prohibited in same car with live poultry or other animals. No dead...

  9. Animal Movement and Establishment of Vaccinia Virus Cantagalo Strain in Amazon Biome, Brazil

    PubMed Central

    Quixabeira-Santos, Jociane Cristina; Medaglia, Maria Luiza G.; Pescador, Caroline A.

    2011-01-01

    To understand the emergence of vaccinia virus Cantagalo strain in the Amazon biome of Brazil, during 2008–2010 we conducted a molecular and epidemiologic survey of poxvirus outbreaks. Data indicate that animal movement was the major cause of virus dissemination within Rondônia State, leading to the establishment and spread of this pathogen. PMID:21470472

  10. Assessing the impact of a cattle risk-based trading scheme on the movement of bovine tuberculosis infected animals in England and Wales.

    PubMed

    Adkin, A; Brouwer, A; Downs, S H; Kelly, L

    2016-01-01

    The adoption of bovine tuberculosis (bTB) risk-based trading (RBT) schemes has the potential to reduce the risk of bTB spread. However, any scheme will have cost implications that need to be balanced against its likely success in reducing bTB. This paper describes the first stochastic quantitative model assessing the impact of the implementation of a cattle risk-based trading scheme to inform policy makers and contribute to cost-benefit analyses. A risk assessment for England and Wales was developed to estimate the number of infected cattle traded using historic movement data recorded between July 2010 and June 2011. Three scenarios were implemented: cattle traded with no RBT scheme in place, voluntary provision of the score and a compulsory, statutory scheme applying a bTB risk score to each farm. For each scenario, changes in trade were estimated due to provision of the risk score to potential purchasers. An estimated mean of 3981 bTB infected animals were sold to purchasers with no RBT scheme in place in one year, with 90% confidence the true value was between 2775 and 5288. This result is dependent on the estimated between herd prevalence used in the risk assessment which is uncertain. With the voluntary provision of the risk score by farmers, on average, 17% of movements was affected (purchaser did not wish to buy once the risk score was available), with a reduction of 23% in infected animals being purchased initially. The compulsory provision of the risk score in a statutory scheme resulted in an estimated mean change to 26% of movements, with a reduction of 37% in infected animals being purchased initially, increasing to a 53% reduction in infected movements from higher risk sellers (score 4 and 5). The estimated mean reduction in infected animals being purchased could be improved to 45% given a 10% reduction in risky purchase behaviour by farmers which may be achieved through education programmes, or to an estimated mean of 49% if a rule was implemented

  11. Modelling the Constraints of Spatial Environment in Fauna Movement Simulations: Comparison of a Boundaries Accurate Function and a Cost Function

    NASA Astrophysics Data System (ADS)

    Jolivet, L.; Cohen, M.; Ruas, A.

    2015-08-01

    Landscape influences fauna movement at different levels, from habitat selection to choices of movements' direction. Our goal is to provide a development frame in order to test simulation functions for animal's movement. We describe our approach for such simulations and we compare two types of functions to calculate trajectories. To do so, we first modelled the role of landscape elements to differentiate between elements that facilitate movements and the ones being hindrances. Different influences are identified depending on landscape elements and on animal species. Knowledge were gathered from ecologists, literature and observation datasets. Second, we analysed the description of animal movement recorded with GPS at fine scale, corresponding to high temporal frequency and good location accuracy. Analysing this type of data provides information on the relation between landscape features and movements. We implemented an agent-based simulation approach to calculate potential trajectories constrained by the spatial environment and individual's behaviour. We tested two functions that consider space differently: one function takes into account the geometry and the types of landscape elements and one cost function sums up the spatial surroundings of an individual. Results highlight the fact that the cost function exaggerates the distances travelled by an individual and simplifies movement patterns. The geometry accurate function represents a good bottom-up approach for discovering interesting areas or obstacles for movements.

  12. 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.

  13. Dynamics of animal movement in an ecological context: dragonfly wing damage reduces flight performance and predation success.

    PubMed

    Combes, S A; Crall, J D; Mukherjee, S

    2010-06-23

    Much of our understanding of the control and dynamics of animal movement derives from controlled laboratory experiments. While many aspects of animal movement can be probed only in these settings, a more complete understanding of animal locomotion may be gained by linking experiments on relatively simple motions in the laboratory to studies of more complex behaviours in natural settings. To demonstrate the utility of this approach, we examined the effects of wing damage on dragonfly flight performance in both a laboratory drop-escape response and the more natural context of aerial predation. The laboratory experiment shows that hindwing area loss reduces vertical acceleration and average flight velocity, and the predation experiment demonstrates that this type of wing damage results in a significant decline in capture success. Taken together, these results suggest that wing damage may take a serious toll on wild dragonflies, potentially reducing both reproductive success and survival.

  14. Dynamics of animal movement in an ecological context: dragonfly wing damage reduces flight performance and predation success

    PubMed Central

    Combes, S. A.; Crall, J. D.; Mukherjee, S.

    2010-01-01

    Much of our understanding of the control and dynamics of animal movement derives from controlled laboratory experiments. While many aspects of animal movement can be probed only in these settings, a more complete understanding of animal locomotion may be gained by linking experiments on relatively simple motions in the laboratory to studies of more complex behaviours in natural settings. To demonstrate the utility of this approach, we examined the effects of wing damage on dragonfly flight performance in both a laboratory drop–escape response and the more natural context of aerial predation. The laboratory experiment shows that hindwing area loss reduces vertical acceleration and average flight velocity, and the predation experiment demonstrates that this type of wing damage results in a significant decline in capture success. Taken together, these results suggest that wing damage may take a serious toll on wild dragonflies, potentially reducing both reproductive success and survival. PMID:20236968

  15. Urban landscape features influencing rodent control and animal movement in two urban areas of California

    EPA Science Inventory

    “Pest” control of both native (e.g., gophers) and exotic (e.g., black rats, house mice) species may impact populations of non-target species inadvertently. We evaluated relationships among animal movement, rodent control, and landscape features in two urban locations in Californ...

  16. Landscape features influencing residential rodent control and animal movement in two urban areas of California

    EPA Science Inventory

    Residential “pest” control of both native (e.g., gophers, rabbits) and exotic (e.g., black and Norway rats, house mice) species may impact populations of non-target species inadvertently. We evaluated relationships among animal movement, rodent control, and landscape features in...

  17. A Novel Rat Model of Orthodontic Tooth Movement Using Temporary Skeletal Anchorage Devices: 3D Finite Element Analysis and In Vivo Validation

    PubMed Central

    Stevenson, Thomas; Doschak, Michael

    2014-01-01

    The aim of this animal study was to develop a model of orthodontic tooth movement using a microimplant as a TSAD in rodents. A finite element model of the TSAD in alveolar bone was built using μCT images of rat maxilla to determine the von Mises stresses and displacement in the alveolar bone surrounding the TSAD. For in vivo validation of the FE model, Sprague-Dawley rats (n = 25) were used and a Stryker 1.2 × 3 mm microimplant was inserted in the right maxilla and used to protract the right first permanent molar using a NiTi closed coil spring. Tooth movement measurements were taken at baseline, 4 and 8 weeks. At 8 weeks, animals were euthanized and tissues were analyzed by histology and EPMA. FE modeling showed maximum von Mises stress of 45 Mpa near the apex of TSAD but the average von Mises stress was under 25 Mpa. Appreciable tooth movement of 0.62 ± 0.04 mm at 4 weeks and 1.99 ± 0.14 mm at 8 weeks was obtained. Histological and EPMA results demonstrated no active bone remodeling around the TSAD at 8 weeks depicting good secondary stability. This study provided evidence that protracted tooth movement is achieved in small animals using TSADs. PMID:25295060

  18. Animal models of tic disorders: a translational perspective.

    PubMed

    Godar, Sean C; Mosher, Laura J; Di Giovanni, Giuseppe; Bortolato, Marco

    2014-12-30

    Tics are repetitive, sudden movements and/or vocalizations, typically enacted as maladaptive responses to intrusive premonitory urges. The most severe tic disorder, Tourette syndrome (TS), is a childhood-onset condition featuring multiple motor and at least one phonic tic for a duration longer than 1 year. The pharmacological treatment of TS is mainly based on antipsychotic agents; while these drugs are often effective in reducing tic severity and frequency, their therapeutic compliance is limited by serious motor and cognitive side effects. The identification of novel therapeutic targets and development of better treatments for tic disorders is conditional on the development of animal models with high translational validity. In addition, these experimental tools can prove extremely useful to test hypotheses on the etiology and neurobiological bases of TS and related conditions. In recent years, the translational value of these animal models has been enhanced, thanks to a significant re-organization of our conceptual framework of neuropsychiatric disorders, with a greater focus on endophenotypes and quantitative indices, rather than qualitative descriptors. Given the complex and multifactorial nature of TS and other tic disorders, the selection of animal models that can appropriately capture specific symptomatic aspects of these conditions can pose significant theoretical and methodological challenges. In this article, we will review the state of the art on the available animal models of tic disorders, based on genetic mutations, environmental interventions as well as pharmacological manipulations. Furthermore, we will outline emerging lines of translational research showing how some of these experimental preparations have led to significant progress in the identification of novel therapeutic targets for tic disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Animal models of tic disorders: A translational perspective

    PubMed Central

    Godar, Sean C.; Mosher, Laura J.; Di Giovanni, Giuseppe; Bortolato, Marco

    2014-01-01

    Tics are repetitive, sudden movements and/or vocalizations, typically enacted as maladaptive responses to intrusive premonitory urges. The most severe tic disorder, Tourette syndrome (TS), is a childhood-onset condition featuring multiple motor and at least one phonic tic for a duration longer than 1 year. The pharmacological treatment of TS is mainly based on antipsychotic agents; while these drugs are often effective in reducing tic severity and frequency, their therapeutic compliance is limited by serious motor and cognitive side effects. The identification of novel therapeutic targets and development of better treatments for tic disorders is conditional on the development of animal models with high translational validity. In addition, these experimental tools can prove extremely useful to test hypotheses on the etiology and neurobiological bases of TS and related conditions. In recent years, the translational value of these animal models has been enhanced, thanks to a significant re-organization of our conceptual framework of neuropsychiatric disorders, with a greater focus on endophenotypes and quantitative indices, rather than qualitative descriptors. Given the complex and multifactorial nature of TS and other tic disorders, the selection of animal models that can appropriately capture specific symptomatic aspects of these conditions can pose significant theoretical and methodological challenges. In this article, we will review the state of the art on the available animal models of tic disorders, based on genetic mutations, environmental interventions as well as pharmacological manipulations. Furthermore, we will outline emerging lines of translational research showing how some of these experimental preparations have led to significant progress in the identification of novel therapeutic targets for tic disorders. PMID:25244952

  20. System identification of perilymphatic fistula in an animal model

    NASA Technical Reports Server (NTRS)

    Wall, C. 3rd; Casselbrant, M. L.

    1992-01-01

    An acute animal model has been developed in the chinchilla for the study of perilymphatic fistulas. Micropunctures were made in three sites to simulate bony, round window, and oval window fistulas. The eye movements in response to pressure applied to the external auditory canal were recorded after micropuncture induction and in preoperative controls. The main pressure stimulus was a pseudorandom binary sequence (PRBS) that rapidly changed between plus and minus 200 mm of water. The PRBS stimulus, with its wide frequency bandwidth, produced responses clearly above the preoperative baseline in 78 percent of the runs. The response was better between 0.5 and 3.3 Hz than it was below 0.5 Hz. The direction of horizontal eye movement was toward the side of the fistula with positive pressure applied in 92 percent of the runs. Vertical eye movements were also observed. The ratio of vertical eye displacement to horizontal eye displacement depended upon the site of the micropuncture induction. Thus, such a ratio measurement may be clinically useful in the noninvasive localization of perilymphatic fistulas in humans.

  1. Animal models of gastrointestinal and liver diseases. Animal models of acute and chronic pancreatitis

    PubMed Central

    Zhan, Xianbao; Wang, Fan; Bi, Yan

    2016-01-01

    Animal models of pancreatitis are useful for elucidating the pathogenesis of pancreatitis and developing and testing novel interventions. In this review, we aim to summarize the most commonly used animal models, overview their pathophysiology, and discuss their strengths and limitations. We will also briefly describe common animal study procedures and refer readers to more detailed protocols in the literature. Although animal models include pigs, dogs, opossums, and other animals, we will mainly focus on rodent models because of their popularity. Autoimmune pancreatitis and genetically engineered animal models will be reviewed elsewhere. PMID:27418683

  2. Image motion environments: background noise for movement-based animal signals.

    PubMed

    Peters, Richard; Hemmi, Jan; Zeil, Jochen

    2008-05-01

    Understanding the evolution of animal signals has to include consideration of the structure of signal and noise, and the sensory mechanisms that detect the signals. Considerable progress has been made in understanding sounds and colour signals, however, the degree to which movement-based signals are constrained by the particular patterns of environmental image motion is poorly understood. Here we have quantified the image motion generated by wind-blown plants at 12 sites in the coastal habitat of the Australian lizard Amphibolurus muricatus. Sampling across different plant communities and meteorological conditions revealed distinct image motion environments. At all locations, image motion became more directional and apparent speed increased as wind speeds increased. The magnitude of these changes and the spatial distribution of image motion, however, varied between locations probably as a function of plant structure and the topographic location. In addition, we show that the background motion noise depends strongly on the particular depth-structure of the environment and argue that such micro-habitat differences suggest specific strategies to preserve signal efficacy. Movement-based signals and motion processing mechanisms, therefore, may reveal the same type of habitat specific structural variation that we see for signals from other modalities.

  3. Mapping migratory flyways in Asia using dynamic Brownian bridge movement models.

    PubMed

    Palm, Eric C; Newman, Scott H; Prosser, Diann J; Xiao, Xiangming; Ze, Luo; Batbayar, Nyambayar; Balachandran, Sivananinthaperumal; Takekawa, John Y

    2015-01-01

    Identifying movement routes and stopover sites is necessary for developing effective management and conservation strategies for migratory animals. In the case of migratory birds, a collection of migration routes, known as a flyway, is often hundreds to thousands of kilometers long and can extend across political boundaries. Flyways encompass the entire geographic range between the breeding and non-breeding areas of a population, species, or a group of species, and they provide spatial frameworks for management and conservation across international borders. Existing flyway maps are largely qualitative accounts based on band returns and survey data rather than observed movement routes. In this study, we use satellite and GPS telemetry data and dynamic Brownian bridge movement models to build upon existing maps and describe waterfowl space use probabilistically in the Central Asian and East Asian-Australasian Flyways. Our approach provided new information on migratory routes that was not easily attainable with existing methods to describe flyways. Utilization distributions from dynamic Brownian bridge movement models identified key staging and stopover sites, migration corridors and general flyway outlines in the Central Asian and East Asian-Australasian Flyways. A map of space use from ruddy shelducks depicted two separate movement corridors within the Central Asian Flyway, likely representing two distinct populations that show relatively strong connectivity between breeding and wintering areas. Bar-headed geese marked at seven locations in the Central Asian Flyway showed heaviest use at several stopover sites in the same general region of high-elevation lakes along the eastern Qinghai-Tibetan Plateau. Our analysis of data from multiple Anatidae species marked at sites throughout Asia highlighted major movement corridors across species and confirmed that the Central Asian and East Asian-Australasian Flyways were spatially distinct. The dynamic Brownian bridge

  4. Expanding Panjabi's stability model to express movement: a theoretical model.

    PubMed

    Hoffman, J; Gabel, P

    2013-06-01

    Novel theoretical models of movement have historically inspired the creation of new methods for the application of human movement. The landmark theoretical model of spinal stability by Panjabi in 1992 led to the creation of an exercise approach to spinal stability. This approach however was later challenged, most significantly due to a lack of favourable clinical effect. The concepts explored in this paper address and consider the deficiencies of Panjabi's model then propose an evolution and expansion from a special model of stability to a general one of movement. It is proposed that two body-wide symbiotic elements are present within all movement systems, stability and mobility. The justification for this is derived from the observable clinical environment. It is clinically recognised that these two elements are present and identifiable throughout the body in different joints and muscles, and the neural conduction system. In order to generalise the Panjabi model of stability to include and illustrate movement, a matching parallel mobility system with the same subsystems was conceptually created. In this expanded theoretical model, the new mobility system is placed beside the existing stability system and subsystems. The ability of both stability and mobility systems to work in harmony will subsequently determine the quality of movement. Conversely, malfunction of either system, or their subsystems, will deleteriously affect all other subsystems and consequently overall movement quality. For this reason, in the rehabilitation exercise environment, focus should be placed on the simultaneous involvement of both the stability and mobility systems. It is suggested that the individual's relevant functional harmonious movements should be challenged at the highest possible level without pain or discomfort. It is anticipated that this conceptual expansion of the theoretical model of stability to one with the symbiotic inclusion of mobility, will provide new understandings

  5. Three-dimensional temporomandibular joint modeling and animation.

    PubMed

    Cascone, Piero; Rinaldi, Fabrizio; Pagnoni, Mario; Marianetti, Tito Matteo; Tedaldi, Massimiliano

    2008-11-01

    The three-dimensional (3D) temporomandibular joint (TMJ) model derives from a study of the cranium by 3D virtual reality and mandibular function animation. The starting point of the project is high-fidelity digital acquisition of a human dry skull. The cooperation between the maxillofacial surgeon and the cartoonist enables the reconstruction of the fibroconnective components of the TMJ that are the keystone for comprehension of the anatomic and functional features of the mandible. The skeletal model is customized with the apposition of the temporomandibular ligament, the articular disk, the retrodiskal tissue, and the medial and the lateral ligament of the disk. The simulation of TMJ movement is the result of the integration of up-to-date data on the biomechanical restrictions. The 3D TMJ model is an easy-to-use application that may be run on a personal computer for the study of the TMJ and its biomechanics.

  6. Modeling white sturgeon movement in a reservoir: The effect of water quality and sturgeon density

    USGS Publications Warehouse

    Sullivan, A.B.; Jager, H.I.; Myers, R.

    2003-01-01

    We developed a movement model to examine the distribution and survival of white sturgeon (Acipenser transmontanus) in a reservoir subject to large spatial and temporal variation in dissolved oxygen and temperature. Temperature and dissolved oxygen were simulated by a CE-QUAL-W2 model of Brownlee Reservoir, Idaho for a typical wet, normal, and dry hydrologic year. We compared current water quality conditions to scenarios with reduced nutrient inputs to the reservoir. White sturgeon habitat quality was modeled as a function of temperature, dissolved oxygen and, in some cases, suitability for foraging and depth. We assigned a quality index to each cell along the bottom of the reservoir. The model simulated two aspects of daily movement. Advective movement simulated the tendency for animals to move toward areas with high habitat quality, and diffusion simulated density dependent movement away from areas with high sturgeon density in areas with non-lethal habitat conditions. Mortality resulted when sturgeon were unable to leave areas with lethal temperature or dissolved oxygen conditions. Water quality was highest in winter and early spring and lowest in mid to late summer. Limiting nutrient inputs reduced the area of Brownlee Reservoir with lethal conditions for sturgeon and raised the average habitat suitability throughout the reservoir. Without movement, simulated white sturgeon survival ranged between 45 and 89%. Allowing movement raised the predicted survival of sturgeon under all conditions to above 90% as sturgeon avoided areas with low habitat quality. ?? 2003 Elsevier B.V. All rights reserved.

  7. Model of Emotional Expressions in Movements

    ERIC Educational Resources Information Center

    Rozaliev, Vladimir L.; Orlova, Yulia A.

    2013-01-01

    This paper presents a new approach to automated identification of human emotions based on analysis of body movements, a recognition of gestures and poses. Methodology, models and automated system for emotion identification are considered. To characterize the person emotions in the model, body movements are described with linguistic variables and a…

  8. Animal models of gastrointestinal and liver diseases. Animal models of acute and chronic pancreatitis.

    PubMed

    Zhan, Xianbao; Wang, Fan; Bi, Yan; Ji, Baoan

    2016-09-01

    Animal models of pancreatitis are useful for elucidating the pathogenesis of pancreatitis and developing and testing novel interventions. In this review, we aim to summarize the most commonly used animal models, overview their pathophysiology, and discuss their strengths and limitations. We will also briefly describe common animal study procedures and refer readers to more detailed protocols in the literature. Although animal models include pigs, dogs, opossums, and other animals, we will mainly focus on rodent models because of their popularity. Autoimmune pancreatitis and genetically engineered animal models will be reviewed elsewhere. Copyright © 2016 the American Physiological Society.

  9. GPS measurement error gives rise to spurious 180 degree turning angles and strong directional biases in animal movement data.

    PubMed

    Hurford, Amy

    2009-05-20

    Movement data are frequently collected using Global Positioning System (GPS) receivers, but recorded GPS locations are subject to errors. While past studies have suggested methods to improve location accuracy, mechanistic movement models utilize distributions of turning angles and directional biases and these data present a new challenge in recognizing and reducing the effect of measurement error. I collected locations from a stationary GPS collar, analyzed a probabilistic model and used Monte Carlo simulations to understand how measurement error affects measured turning angles and directional biases. Results from each of the three methods were in complete agreement: measurement error gives rise to a systematic bias where a stationary animal is most likely to be measured as turning 180 degrees or moving towards a fixed point in space. These spurious effects occur in GPS data when the measured distance between locations is <20 meters. Measurement error must be considered as a possible cause of 180 degree turning angles in GPS data. Consequences of failing to account for measurement error are predicting overly tortuous movement, numerous returns to previously visited locations, inaccurately predicting species range, core areas, and the frequency of crossing linear features. By understanding the effect of GPS measurement error, ecologists are able to disregard false signals to more accurately design conservation plans for endangered wildlife.

  10. Real-time animation software for customized training to use motor prosthetic systems.

    PubMed

    Davoodi, Rahman; Loeb, Gerald E

    2012-03-01

    Research on control of human movement and development of tools for restoration and rehabilitation of movement after spinal cord injury and amputation can benefit greatly from software tools for creating precisely timed animation sequences of human movement. Despite their ability to create sophisticated animation and high quality rendering, existing animation software are not adapted for application to neural prostheses and rehabilitation of human movement. We have developed a software tool known as MSMS (MusculoSkeletal Modeling Software) that can be used to develop models of human or prosthetic limbs and the objects with which they interact and to animate their movement using motion data from a variety of offline and online sources. The motion data can be read from a motion file containing synthesized motion data or recordings from a motion capture system. Alternatively, motion data can be streamed online from a real-time motion capture system, a physics-based simulation program, or any program that can produce real-time motion data. Further, animation sequences of daily life activities can be constructed using the intuitive user interface of Microsoft's PowerPoint software. The latter allows expert and nonexpert users alike to assemble primitive movements into a complex motion sequence with precise timing by simply arranging the order of the slides and editing their properties in PowerPoint. The resulting motion sequence can be played back in an open-loop manner for demonstration and training or in closed-loop virtual reality environments where the timing and speed of animation depends on user inputs. These versatile animation utilities can be used in any application that requires precisely timed animations but they are particularly suited for research and rehabilitation of movement disorders. MSMS's modeling and animation tools are routinely used in a number of research laboratories around the country to study the control of movement and to develop and test

  11. Animal models of addiction

    PubMed Central

    Spanagel, Rainer

    2017-01-01

    In recent years, animal models in psychiatric research have been criticized for their limited translational value to the clinical situation. Failures in clinical trials have thus often been attributed to the lack of predictive power of preclinical animal models. Here, I argue that animal models of voluntary drug intake—under nonoperant and operant conditions—and addiction models based on the Diagnostic and Statistical Manual of Mental Disorders are crucial and informative tools for the identification of pathological mechanisms, target identification, and drug development. These models provide excellent face validity, and it is assumed that the neurochemical and neuroanatomical substrates involved in drug-intake behavior are similar in laboratory rodents and humans. Consequently, animal models of drug consumption and addiction provide predictive validity. This predictive power is best illustrated in alcohol research, in which three approved medications—acamprosate, naltrexone, and nalmefene—were developed by means of animal models and then successfully translated into the clinical situation. PMID:29302222

  12. Modelling the variation in skin-test tuberculin reactions, post-mortem lesion counts and case pathology in tuberculosis-exposed cattle: Effects of animal characteristics, histories and co-infection.

    PubMed

    Byrne, A W; Graham, J; Brown, C; Donaghy, A; Guelbenzu-Gonzalo, M; McNair, J; Skuce, R A; Allen, A; McDowell, S W

    2018-06-01

    Correctly identifying bovine tuberculosis (bTB) in cattle remains a significant problem in endemic countries. We hypothesized that animal characteristics (sex, age, breed), histories (herd effects, testing, movement) and potential exposure to other pathogens (co-infection; BVDV, liver fluke and Mycobacterium avium reactors) could significantly impact the immune responsiveness detected at skin testing and the variation in post-mortem pathology (confirmation) in bTB-exposed cattle. Three model suites were developed using a retrospective observational data set of 5,698 cattle culled during herd breakdowns in Northern Ireland. A linear regression model suggested that antemortem tuberculin reaction size (difference in purified protein derivative avium [PPDa] and bovine [PPDb] reactions) was significantly positively associated with post-mortem maximum lesion size and the number of lesions found. This indicated that reaction size could be considered a predictor of both the extent (number of lesions/tissues) and the pathological progression of infection (maximum lesion size). Tuberculin reaction size was related to age class, and younger animals (<2.85 years) displayed larger reaction sizes than older animals. Tuberculin reaction size was also associated with breed and animal movement and increased with the time between the penultimate and disclosing tests. A negative binomial random-effects model indicated a significant increase in lesion counts for animals with M. avium reactions (PPDb-PPDa < 0) relative to non-reactors (PPDb-PPDa = 0). Lesion counts were significantly increased in animals with previous positive severe interpretation skin-test results. Animals with increased movement histories, young animals and non-dairy breed animals also had significantly increased lesion counts. Animals from herds that had BVDV-positive cattle had significantly lower lesion counts than animals from herds without evidence of BVDV infection. Restricting the data set to only

  13. Verification of models for ballistic movement time and endpoint variability.

    PubMed

    Lin, Ray F; Drury, Colin G

    2013-01-01

    A hand control movement is composed of several ballistic movements. The time required in performing a ballistic movement and its endpoint variability are two important properties in developing movement models. The purpose of this study was to test potential models for predicting these two properties. Twelve participants conducted ballistic movements of specific amplitudes using a drawing tablet. The measured data of movement time and endpoint variability were then used to verify the models. This study was successful with Hoffmann and Gan's movement time model (Hoffmann, 1981; Gan and Hoffmann 1988) predicting more than 90.7% data variance for 84 individual measurements. A new theoretically developed ballistic movement variability model, proved to be better than Howarth, Beggs, and Bowden's (1971) model, predicting on average 84.8% of stopping-variable error and 88.3% of aiming-variable errors. These two validated models will help build solid theoretical movement models and evaluate input devices. This article provides better models for predicting end accuracy and movement time of ballistic movements that are desirable in rapid aiming tasks, such as keying in numbers on a smart phone. The models allow better design of aiming tasks, for example button sizes on mobile phones for different user populations.

  14. Population consequences of aggregative movement

    Treesearch

    Peter Turchin

    1989-01-01

    Gregarious behaviour is an important factor influencing survival and reproduction of animals, as well as population interactions. In this paper I develop a model of movement with attraction or repulsion between conspecifics. To facilitate its use in empirical studies, the model is based on experimentally measurable features of individual behaviour.

  15. Comparative study between two animal models of extrapyramidal movement disorders: prevention and reversion by pecan nut shell aqueous extract.

    PubMed

    Trevizol, Fabiola; Benvegnú, Dalila M; Barcelos, Raquel C S; Pase, Camila S; Segat, Hecson J; Dias, Verônica Tironi; Dolci, Geisa S; Boufleur, Nardeli; Reckziegel, Patrícia; Bürger, Marilise E

    2011-08-01

    Acute reserpine and subchronic haloperidol are animal models of extrapyramidal disorders often used to study parkinsonism, akinesia and tardive dyskinesia. In humans, these usually irreversible and disabling extrapyramidal disorders are developed by typical antipsychotic treatment, whose pathophysiology has been related to oxidative damages development. So far, there is no treatment to prevent these problems of the psychiatric clinic, and therefore further studies are needed. Here we used the animal models of extrapyramidal disorders cited above, which were performed in two distinct experiments: orofacial dyskinesia (OD)/catalepsy induced by acute reserpine and subchronic haloperidol after (experiment 1) and before (experiment 2) oral treatment with pecan shell aqueous extract (AE), a natural and promissory antioxidant. When administered previously (exp.1), the AE prevented OD and catalepsy induced by both reserpine and haloperidol. When reserpine and haloperidol were administered before the extract (exp.2), the animals developed OD and catalepsy all the same. However, the orofacial parameter (but not catalepsy) in both animal models was reversed after 7 and 14 days of AE treatment. These results indicate that, acute reserpine and subchronic haloperidol administrations induced similar motor disorders, although through different mechanisms, and therefore are important animal models to study the physiopathology of extrapyramidal disorders. Comparatively, the pecan shell AE was able to both prevent and reverse OD but only to prevent catalepsy. These results reinforce the role of oxidative stress and validate the two animal models used here. Our findings also favor the idea of prevention of extrapyramidal disorders, rather than their reversal. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. A Heterogeneous Wireless Identification Network for the Localization of Animals Based on Stochastic Movements

    PubMed Central

    Gutiérrez, Álvaro; González, Carlos; Jiménez-Leube, Javier; Zazo, Santiago; Dopico, Nelson; Raos, Ivana

    2009-01-01

    The improvement in the transmission range in wireless applications without the use of batteries remains a significant challenge in identification applications. In this paper, we describe a heterogeneous wireless identification network mostly powered by kinetic energy, which allows the localization of animals in open environments. The system relies on radio communications and a global positioning system. It is made up of primary and secondary nodes. Secondary nodes are kinetic-powered and take advantage of animal movements to activate the node and transmit a specific identifier, reducing the number of batteries of the system. Primary nodes are battery-powered and gather secondary-node transmitted information to provide it, along with position and time data, to a final base station in charge of the animal monitoring. The system allows tracking based on contextual information obtained from statistical data. PMID:22412344

  17. Experimental Animal Models for Studies on the Mechanisms of Blast-Induced Neurotrauma

    PubMed Central

    Risling, Mårten; Davidsson, Johan

    2012-01-01

    A blast injury is a complex type of physical trauma resulting from the detonation of explosive compounds and has become an important issue due to the use of improvised explosive devices (IED) in current military conflicts. Blast-induced neurotrauma (BINT) is a major concern in contemporary military medicine and includes a variety of injuries that range from mild to lethal. Extreme forces and their complex propagation characterize BINT. Modern body protection and the development of armored military vehicles can be assumed to have changed the outcome of BINT. Primary blast injuries are caused by overpressure waves whereas secondary, tertiary, and quaternary blast injuries can have more varied origins such as the impact of fragments, abnormal movements, or heat. The characteristics of the blast wave can be assumed to be significantly different in open field detonations compared to explosions in a confined space, such an armored vehicle. Important parameters include peak pressure, duration, and shape of the pulse. Reflections from walls and armor can make the prediction of effects in individual cases very complex. Epidemiological data do not contain information of the comparative importance of the different blast mechanisms. It is therefore important to generate data in carefully designed animal models. Such models can be selective reproductions of a primary blast, penetrating injuries from fragments, acceleration movements, or combinations of such mechanisms. It is of crucial importance that the physical parameters of the employed models are well characterized so that the experiments can be reproduced in different laboratory settings. Ideally, pressure recordings should be calibrated by using the same equipment in several laboratories. With carefully designed models and thoroughly evaluated animal data it should be possible to achieve a translation of data between animal and clinical data. Imaging and computer simulation represent a possible link between experiments

  18. Modelling Farm Animal Welfare

    PubMed Central

    Collins, Lisa M.; Part, Chérie E.

    2013-01-01

    Simple Summary In this review paper we discuss the different modeling techniques that have been used in animal welfare research to date. We look at what questions they have been used to answer, the advantages and pitfalls of the methods, and how future research can best use these approaches to answer some of the most important upcoming questions in farm animal welfare. Abstract The use of models in the life sciences has greatly expanded in scope and advanced in technique in recent decades. However, the range, type and complexity of models used in farm animal welfare is comparatively poor, despite the great scope for use of modeling in this field of research. In this paper, we review the different modeling approaches used in farm animal welfare science to date, discussing the types of questions they have been used to answer, the merits and problems associated with the method, and possible future applications of each technique. We find that the most frequently published types of model used in farm animal welfare are conceptual and assessment models; two types of model that are frequently (though not exclusively) based on expert opinion. Simulation, optimization, scenario, and systems modeling approaches are rarer in animal welfare, despite being commonly used in other related fields. Finally, common issues such as a lack of quantitative data to parameterize models, and model selection and validation are discussed throughout the review, with possible solutions and alternative approaches suggested. PMID:26487411

  19. An information maximization model of eye movements

    NASA Technical Reports Server (NTRS)

    Renninger, Laura Walker; Coughlan, James; Verghese, Preeti; Malik, Jitendra

    2005-01-01

    We propose a sequential information maximization model as a general strategy for programming eye movements. The model reconstructs high-resolution visual information from a sequence of fixations, taking into account the fall-off in resolution from the fovea to the periphery. From this framework we get a simple rule for predicting fixation sequences: after each fixation, fixate next at the location that minimizes uncertainty (maximizes information) about the stimulus. By comparing our model performance to human eye movement data and to predictions from a saliency and random model, we demonstrate that our model is best at predicting fixation locations. Modeling additional biological constraints will improve the prediction of fixation sequences. Our results suggest that information maximization is a useful principle for programming eye movements.

  20. Animal Model of Dermatophytosis

    PubMed Central

    Shimamura, Tsuyoshi; Kubota, Nobuo; Shibuya, Kazutoshi

    2012-01-01

    Dermatophytosis is superficial fungal infection caused by dermatophytes that invade the keratinized tissue of humans and animals. Lesions from dermatophytosis exhibit an inflammatory reaction induced to eliminate the invading fungi by using the host's normal immune function. Many scientists have attempted to establish an experimental animal model to elucidate the pathogenesis of human dermatophytosis and evaluate drug efficacy. However, current animal models have several issues. In the present paper, we surveyed reports about the methodology of the dermatophytosis animal model for tinea corporis, tinea pedis, and tinea unguium and discussed future prospects. PMID:22619489

  1. Animal models of human immunodeficiency virus infection. Public Health Service Animal Models Committee.

    PubMed

    Spertzel, R O

    1989-12-01

    The search for a model of HIV infection continues. While much of the initial work focussed on animal models of AIDS, more recent efforts have sought animal models of HIV infection in which one or more signs of AIDS may be reproduced. Most initial small animal modelling efforts were negative and many such efforts remain unpublished. In 1988, the Public Health Service (PHS) AIDS Animal Model Committee conducted a survey among PHS agencies to identify published and unpublished data on animal models of HIV. To date, the chimpanzee is the only animal to be reliably infected with HIV albeit without development of signs and symptoms normally associated with human AIDS. One recent study has shown the gibbon to be similarly susceptible to infection with HIV. Mice carrying a chimera of elements of the human immune system have been shown to support the growth of HIV and F1 progeny of transgenic mice containing intact copies of HIV proviral DNA, have developed a disease that resembles some aspects of human AIDS. Rabbits, baboons and rhesus monkeys have also been shown to be infected under certain conditions and/or with selected strains of HIV but again without the development of AIDS symptomatology. This report briefly summarizes published and available unpublished data on these efforts to develop an animal model of HIV infection.

  2. The virtual craniofacial patient: 3D jaw modeling and animation.

    PubMed

    Enciso, Reyes; Memon, Ahmed; Fidaleo, Douglas A; Neumann, Ulrich; Mah, James

    2003-01-01

    In this paper, we present new developments in the area of 3D human jaw modeling and animation. CT (Computed Tomography) scans have traditionally been used to evaluate patients with dental implants, assess tumors, cysts, fractures and surgical procedures. More recently this data has been utilized to generate models. Researchers have reported semi-automatic techniques to segment and model the human jaw from CT images and manually segment the jaw from MRI images. Recently opto-electronic and ultrasonic-based systems (JMA from Zebris) have been developed to record mandibular position and movement. In this research project we introduce: (1) automatic patient-specific three-dimensional jaw modeling from CT data and (2) three-dimensional jaw motion simulation using jaw tracking data from the JMA system (Zebris).

  3. Scripting human animations in a virtual environment

    NASA Technical Reports Server (NTRS)

    Goldsby, Michael E.; Pandya, Abhilash K.; Maida, James C.

    1994-01-01

    The current deficiencies of virtual environment (VE) are well known: annoying lag time in drawing the current view, drastically simplified environments to reduce that time lag, low resolution and narrow field of view. Animation scripting is an application of VE technology which can be carried out successfully despite these deficiencies. The final product is a smoothly moving high resolution animation displaying detailed models. In this system, the user is represented by a human computer model with the same body proportions. Using magnetic tracking, the motions of the model's upper torso, head and arms are controlled by the user's movements (18 degrees of freedom). The model's lower torso and global position and orientation are controlled by a spaceball and keypad (12 degrees of freedom). Using this system human motion scripts can be extracted from the user's movements while immersed in a simplified virtual environment. Recorded data is used to define key frames; motion is interpolated between them and post processing adds a more detailed environment. The result is a considerable savings in time and a much more natural-looking movement of a human figure in a smooth and seamless animation.

  4. Nicolaus Steno's new myology (1667): rather than muscle, the motorfibre should be called animal's organ of movement.

    PubMed

    Kardel, Troels

    2008-01-01

    Muscular movement is the result of fibre shortening. How did this basic insight arise? Based on several of his observations, Nicolaus Steno in 1664 and 1667 proposed that muscles shorten when fibres shorten, and that skeletal muscles consist of uniform motor fibres layered as pennate structures. The basis for a new myology was provided in a geometrical model of the movement of the muscles. But fibre shortening was incompatible with the dominant ancient theory of contraction by inflation that was favoured by Descartes and by Steno's contemporaries William Croone, Thomas Willis, John Mayow, and Giovanni Borelli due to their adherence to the Aristotelian axiom: "Anything which moves is moved by something else". The inflation theory blindfolded researchers well into the eighteenth century for skeletal and heart muscles. When the shortening of motor fibres was eventually visualised by microscopy, this inflation theory was no longer tenable. Steno's structural claim on skeletal muscles was also rejected by Borelli and by later commentators. Pennate muscles were only rarely displayed until 1981 when macro-anatomical studies showed the morphology of most skeletal muscles to be similar to that described by Steno. Steno's proposals on muscles have since become a common-place in computer models applied in the study of human and animal motion.

  5. Tremorolytic effects of safinamide in animal models of drug-induced parkinsonian tremor.

    PubMed

    Podurgiel, Samantha; Collins-Praino, Lyndsey E; Yohn, Samantha; Randall, Patrick A; Roach, Arthur; Lobianco, Christophe; Salamone, John D

    2013-04-01

    Safinamide is an α-aminoamide derivative that is currently in Phase III clinical trial development as an add-on therapy to levodopa or dopamine agonists for patients with Parkinson's disease. Safinamide is a monoamine oxidase B inhibitor with additional non-dopaminergic actions. The present experiments were performed to evaluate the ability of safinamide to attenuate parkinsonian motor impairments using the tremulous jaw movement model, an animal model of parkinsonian tremor. In rats, tremulous jaw movements can be induced with dopamine (DA) antagonists, DA depletion, and cholinomimetics, and can be reversed by various antiparkinsonian drugs, including L-DOPA, DA agonists, anticholinergics and adenosine A2A antagonists. In these present experiments, tremulous jaw movements were induced with the anticholinesterase galantamine (3.0mg/kg IP), the muscarinic agonist pilocarpine (0.5mg/kg IP), and the dopamine D2 antagonist pimozide (1.0mg/kg IP). Safinamide significantly reduced the number of tremulous jaw movements induced by galantamine, pilocarpine, and pimozide, with consistent effects across all three drugs at a dose range of 5.0-10.0mg/kg. The results of this study support the use of safinamide as a treatment for parkinsonian tremor. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Animal welfare and use of silkworm as a model animal.

    PubMed

    Sekimizu, N; Paudel, A; Hamamoto, H

    2012-08-01

    Sacrificing model animals is required for developing effective drugs before being used in human beings. In Japan today, at least 4,210,000 mice and other mammals are sacrificed to a total of 6,140,000 per year for the purpose of medical studies. All the animals treated in Japan, including test animals, are managed under control of "Act on Welfare and Management of Animals". Under the principle of this Act, no person shall kill, injure, or inflict cruelty on animals without due cause. "Animal" addressed in the Act can be defined as a "vertebrate animal". If we can make use of invertebrate animals in testing instead of vertebrate ones, that would be a remarkable solution for the issue of animal welfare. Furthermore, there are numerous advantages of using invertebrate animal models: less space and small equipment are enough for taking care of a large number of animals and thus are cost-effective, they can be easily handled, and many biological processes and genes are conserved between mammals and invertebrates. Today, many invertebrates have been used as animal models, but silkworms have many beneficial traits compared to mammals as well as other insects. In a Genome Pharmaceutical Institute's study, we were able to achieve a lot making use of silkworms as model animals. We would like to suggest that pharmaceutical companies and institutes consider the use of the silkworm as a model animal which is efficacious both for financial value by cost cutting and ethical aspects in animals' welfare.

  7. Myeloproliferative Neoplasm Animal Models

    PubMed Central

    Mullally, Ann; Lane, Steven W.; Brumme, Kristina; Ebert, Benjamin L.

    2012-01-01

    Synopsis Myeloproliferative neoplasm (MPN) animal models accurately re-capitulate human disease in mice and have been an important tool for the study of MPN biology and therapy. Transplantation of BCR-ABL transduced bone marrow cells into irradiated syngeneic mice established the field of MPN animal modeling and the retroviral bone marrow transplantation (BMT) assay has been used extensively since. Genetically engineered MPN animal models have enabled detailed characterization of the effects of specific MPN associated genetic abnormalities on the hematopoietic stem and progenitor cell (HSPC) compartment and xenograft models have allowed the study of primary human MPN-propagating cells in vivo. All models have facilitated the pre-clinical development of MPN therapies. JAK2V617F, the most common molecular abnormality in BCR-ABL negative MPN, has been extensively studied using retroviral, transgenic, knock-in and xenograft models. MPN animal models have also been used to investigate additional genetic lesions found in human MPN and to evaluate the bone marrow microenvironment in these diseases. Finally, several genetic lesions, although not common, somatically mutated drivers of MPN in humans induce a MPN phenotype in mice. Future uses for MPN animal models will include modeling compound genetic lesions in MPN and studying myelofibrotic transformation. PMID:23009938

  8. Piperidine, pyridine alkaloid inhibition of fetal movement in a day 40 pregnant goat model.

    PubMed

    Green, Benedict T; Lee, Stephen T; Welch, Kevin D; Pfister, James A; Panter, Kip E

    2013-08-01

    Inhibition of fetal movement is one mechanism behind the development of multiple congenital contracture-type defects in developing fetuses of humans and animals. We tested the alkaloids anabasine, lobeline, and myosmine for agonist actions, and sensitivity to alpha conotoxins EI and GI blockade at fetal muscle-type nicotinic acetylcholine receptors (nAChR) expressed by TE-671 cells. We also determined if the alkaloids decreased fetal movement in an IV dosed, day 40 pregnant goat model. In TE-671 cells, all three alkaloids elicited concentration-dependent changes in membrane potential sensing dye fluorescence. 1.0 μM alpha conotoxin GI shifted the concentration-effect curves of anabasine and myosmine to the right, and decreased maximal responses. Neither of the conotoxins blocked the actions of lobeline in TE-671 cells. In the day 40 pregnant goats, 0.8 mg/kg anabasine abolished fetal movement at 30 and 60 min after dosing and fetal movement was reduced by lobeline and myosmine. The blockade of anabasine and myosmine actions in TE-671 cells by alpha conotoxin GI indicates that they are agonists at fetal muscle-type nAChR. All three alkaloids did significantly decrease fetal movement in the day 40 pregnant goat model suggesting a potential for these alkaloids to cause multiple congenital contracture-type defects in developing fetuses. Published by Elsevier Ltd.

  9. Implementing a modeling software for animated protein-complex interactions using a physics simulation library.

    PubMed

    Ueno, Yutaka; Ito, Shuntaro; Konagaya, Akihiko

    2014-12-01

    To better understand the behaviors and structural dynamics of proteins within a cell, novel software tools are being developed that can create molecular animations based on the findings of structural biology. This study proposes our method developed based on our prototypes to detect collisions and examine the soft-body dynamics of molecular models. The code was implemented with a software development toolkit for rigid-body dynamics simulation and a three-dimensional graphics library. The essential functions of the target software system included the basic molecular modeling environment, collision detection in the molecular models, and physical simulations of the movement of the model. Taking advantage of recent software technologies such as physics simulation modules and interpreted scripting language, the functions required for accurate and meaningful molecular animation were implemented efficiently.

  10. DynAOI: a tool for matching eye-movement data with dynamic areas of interest in animations and movies.

    PubMed

    Papenmeier, Frank; Huff, Markus

    2010-02-01

    Analyzing gaze behavior with dynamic stimulus material is of growing importance in experimental psychology; however, there is still a lack of efficient analysis tools that are able to handle dynamically changing areas of interest. In this article, we present DynAOI, an open-source tool that allows for the definition of dynamic areas of interest. It works automatically with animations that are based on virtual three-dimensional models. When one is working with videos of real-world scenes, a three-dimensional model of the relevant content needs to be created first. The recorded eye-movement data are matched with the static and dynamic objects in the model underlying the video content, thus creating static and dynamic areas of interest. A validation study asking participants to track particular objects demonstrated that DynAOI is an efficient tool for handling dynamic areas of interest.

  11. Collective movement in ecology: from emerging technologies to conservation and management.

    PubMed

    Westley, Peter A H; Berdahl, Andrew M; Torney, Colin J; Biro, Dora

    2018-05-19

    Recent advances in technology and quantitative methods have led to the emergence of a new field of study that stands to link insights of researchers from two closely related, but often disconnected disciplines: movement ecology and collective animal behaviour. To date, the field of movement ecology has focused on elucidating the internal and external drivers of animal movement and the influence of movement on broader ecological processes. Typically, tracking and/or remote sensing technology is employed to study individual animals in natural conditions. By contrast, the field of collective behaviour has quantified the significant role social interactions play in the decision-making of animals within groups and, to date, has predominantly relied on controlled laboratory-based studies and theoretical models owing to the constraints of studying interacting animals in the field. This themed issue is intended to formalize the burgeoning field of collective movement ecology which integrates research from both movement ecology and collective behaviour. In this introductory paper, we set the stage for the issue by briefly examining the approaches and current status of research in these areas. Next, we outline the structure of the theme issue and describe the obstacles collective movement researchers face, from data acquisition in the field to analysis and problems of scale, and highlight the key contributions of the assembled papers. We finish by presenting research that links individual and broad-scale ecological and evolutionary processes to collective movement, and finally relate these concepts to emerging challenges for the management and conservation of animals on the move in a world that is increasingly impacted by human activity.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Author(s).

  12. 9 CFR 78.34 - Other movements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Other movements. 78.34 Section 78.34... Interstate Movement of Swine Because of Brucellosis § 78.34 Other movements. The Administrator may, upon request in specific cases, permit the movement in interstate commerce of swine not otherwise provided for...

  13. 9 CFR 78.25 - Other movements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Other movements. 78.25 Section 78.25... Interstate Movement of Bison Because of Brucellosis § 78.25 Other movements. The Administrator may, upon request in specific cases, permit the interstate movement of bison not otherwise provided for in this...

  14. 9 CFR 78.13 - Other movements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Other movements. 78.13 Section 78.13... Interstate Movement of Cattle Because of Brucellosis § 78.13 Other movements. The Administrator may, upon request in specific cases, permit the interstate movement of cattle not otherwise provided for in this...

  15. Realistic facial animation generation based on facial expression mapping

    NASA Astrophysics Data System (ADS)

    Yu, Hui; Garrod, Oliver; Jack, Rachael; Schyns, Philippe

    2014-01-01

    Facial expressions reflect internal emotional states of a character or in response to social communications. Though much effort has been taken to generate realistic facial expressions, it still remains a challenging topic due to human being's sensitivity to subtle facial movements. In this paper, we present a method for facial animation generation, which reflects true facial muscle movements with high fidelity. An intermediate model space is introduced to transfer captured static AU peak frames based on FACS to the conformed target face. And then dynamic parameters derived using a psychophysics method is integrated to generate facial animation, which is assumed to represent natural correlation of multiple AUs. Finally, the animation sequence in the intermediate model space is mapped to the target face to produce final animation.

  16. A method to quantify movement activity of groups of animals using automated image analysis

    NASA Astrophysics Data System (ADS)

    Xu, Jianyu; Yu, Haizhen; Liu, Ying

    2009-07-01

    Most physiological and environmental changes are capable of inducing variations in animal behavior. The behavioral parameters have the possibility to be measured continuously in-situ by a non-invasive and non-contact approach, and have the potential to be used in the actual productions to predict stress conditions. Most vertebrates tend to live in groups, herds, flocks, shoals, bands, packs of conspecific individuals. Under culture conditions, the livestock or fish are in groups and interact on each other, so the aggregate behavior of the group should be studied rather than that of individuals. This paper presents a method to calculate the movement speed of a group of animal in a enclosure or a tank denoted by body length speed that correspond to group activity using computer vision technique. Frame sequences captured at special time interval were subtracted in pairs after image segmentation and identification. By labeling components caused by object movement in difference frame, the projected area caused by the movement of every object in the capture interval was calculated; this projected area was divided by the projected area of every object in the later frame to get body length moving distance of each object, and further could obtain the relative body length speed. The average speed of all object can well respond to the activity of the group. The group activity of a tilapia (Oreochromis niloticus) school to high (2.65 mg/L) levels of unionized ammonia (UIA) concentration were quantified based on these methods. High UIA level condition elicited a marked increase in school activity at the first hour (P<0.05) exhibiting an avoidance reaction (trying to flee from high UIA condition), and then decreased gradually.

  17. feedr and animalnexus.ca: A paired R package and user-friendly Web application for transforming and visualizing animal movement data from static stations.

    PubMed

    LaZerte, Stefanie E; Reudink, Matthew W; Otter, Ken A; Kusack, Jackson; Bailey, Jacob M; Woolverton, Austin; Paetkau, Mark; de Jong, Adriaan; Hill, David J

    2017-10-01

    Radio frequency identification (RFID) provides a simple and inexpensive approach for examining the movements of tagged animals, which can provide information on species behavior and ecology, such as habitat/resource use and social interactions. In addition, tracking animal movements is appealing to naturalists, citizen scientists, and the general public and thus represents a tool for public engagement in science and science education. Although a useful tool, the large amount of data collected using RFID may quickly become overwhelming. Here, we present an R package (feedr) we have developed for loading, transforming, and visualizing time-stamped, georeferenced data, such as RFID data collected from static logger stations. Using our package, data can be transformed from raw RFID data to visits, presence (regular detections by a logger over time), movements between loggers, displacements, and activity patterns. In addition, we provide several conversion functions to allow users to format data for use in functions from other complementary R packages. Data can also be visualized through static or interactive maps or as animations over time. To increase accessibility, data can be transformed and visualized either through R directly, or through the companion site: http://animalnexus.ca, an online, user-friendly, R-based Shiny Web application. This system can be used by professional and citizen scientists alike to view and study animal movements. We have designed this package to be flexible and to be able to handle data collected from other stationary sources (e.g., hair traps, static very high frequency (VHF) telemetry loggers, observations of marked individuals in colonies or staging sites), and we hope this framework will become a meeting point for science, education, and community awareness of the movements of animals. We aim to inspire citizen engagement while simultaneously enabling robust scientific analysis.

  18. [The three-dimensional simulation of arytenoid cartilage movement].

    PubMed

    Zhang, Jun; Wang, Xuefeng

    2011-08-01

    Exploring the characteristics of arytenoid cartilage movement. Using Pro/ENGINEER (Pro/E) software, the cricoid cartilage, arytenoid cartilage and vocal cords were simulated to the three-dimensional reconstruction, by analyzing the trajectory of arytenoid cartilage in the joint surface from the cricoid cartilage and arytenoid cartilage composition. The 3D animation simulation showed the normal movement patterns of the vocal cords and the characteristics of vocal cords movement in occasion of arytenoid cartilage dislocation vividly. The three-dimensional model has clinical significance for arytenoid cartilage movement disorders.

  19. 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

  20. Animal Models of Colorectal Cancer

    PubMed Central

    Johnson, Robert L.; Fleet, James C.

    2012-01-01

    Colorectal cancer is a heterogeneous disease that afflicts a large number of people in the United States. The use of animal models has the potential to increase our understanding of carcinogenesis, tumor biology, and the impact of specific molecular events on colon biology. In addition, animal models with features of specific human colorectal cancers can be used to test strategies for cancer prevention and treatment. In this review we provide an overview of the mechanisms driving human cancer, we discuss the approaches one can take to model colon cancer in animals, and we describe a number of specific animal models that have been developed for the study of colon cancer. We believe that there are many valuable animal models to study various aspects of human colorectal cancer. However, opportunities for improving upon these models exist. PMID:23076650

  1. Animal models of tinnitus.

    PubMed

    Brozoski, Thomas J; Bauer, Carol A

    2016-08-01

    Presented is a thematic review of animal tinnitus models from a functional perspective. Chronic tinnitus is a persistent subjective sound sensation, emergent typically after hearing loss. Although the sensation is experientially simple, it appears to have central a nervous system substrate of unexpected complexity that includes areas outside of those classically defined as auditory. Over the past 27 years animal models have significantly contributed to understanding tinnitus' complex neurophysiology. In that time, a diversity of models have been developed, each with its own strengths and limitations. None has clearly become a standard. Animal models trace their origin to the 1988 experiments of Jastreboff and colleagues. All subsequent models derive some of their features from those experiments. Common features include behavior-dependent psychophysical determination, acoustic conditions that contrast objective sound and silence, and inclusion of at least one normal-hearing control group. In the present review, animal models have been categorized as either interrogative or reflexive. Interrogative models use emitted behavior under voluntary control to indicate hearing. An example would be pressing a lever to obtain food in the presence of a particular sound. In this type of model animals are interrogated about their auditory sensations, analogous to asking a patient, "What do you hear?" These models require at least some training and motivation management, and reflect the perception of tinnitus. Reflexive models, in contrast, employ acoustic modulation of an auditory reflex, such as the acoustic startle response. An unexpected loud sound will elicit a reflexive motor response from many species, including humans. Although involuntary, acoustic startle can be modified by a lower-level preceding event, including a silent sound gap. Sound-gap modulation of acoustic startle appears to discriminate tinnitus in animals as well as humans, and requires no training or

  2. 9 CFR 78.34 - Other movements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.34 Other movements. The Administrator may, upon... spread of brucellosis. The Administrator shall promptly notify the State animal health officials of the...

  3. 9 CFR 78.25 - Other movements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.25 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  4. 9 CFR 78.13 - Other movements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.13 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  5. 9 CFR 78.25 - Other movements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.25 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  6. 9 CFR 78.34 - Other movements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.34 Other movements. The Administrator may, upon... spread of brucellosis. The Administrator shall promptly notify the State animal health officials of the...

  7. 9 CFR 78.13 - Other movements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.13 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  8. 9 CFR 78.13 - Other movements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.13 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  9. 9 CFR 78.25 - Other movements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.25 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  10. 9 CFR 78.25 - Other movements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.25 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  11. 9 CFR 78.34 - Other movements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.34 Other movements. The Administrator may, upon... spread of brucellosis. The Administrator shall promptly notify the State animal health officials of the...

  12. 9 CFR 78.34 - Other movements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.34 Other movements. The Administrator may, upon... spread of brucellosis. The Administrator shall promptly notify the State animal health officials of the...

  13. 9 CFR 78.13 - Other movements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.13 Other movements. The Administrator may, upon... brucellosis. The Administrator shall promptly notify the State animal health officials of the States involved...

  14. What is the philosophy of modelling soil moisture movement?

    NASA Astrophysics Data System (ADS)

    Chen, J.; Wu, Y.

    2009-12-01

    In laboratory, the soil moisture movement in the different soil textures has been analysed. From field investigation, at a spot, the soil moisture movement in the root zone, vadose zone and shallow aquifer has been explored. In addition, on ground slopes, the interflow in the near surface soil layers has been studied. Along the regions near river reaches, the expansion and shrink of the saturated area due to rainfall occurrences have been observed. From those previous explorations regarding soil moisture movement, numerical models to represent this hydrologic process have been developed. However, generally, due to high heterogeneity and stratification of soil in a basin, modelling soil moisture movement is rather challenging. Normally, some empirical equations or artificial manipulation are employed to adjust the soil moisture movement in various numerical models. In this study, we inspect the soil moisture movement equations used in a watershed model, SWAT (Soil and Water Assessment Tool) (Neitsch et al., 2005), to examine the limitations of our knowledge in such a hydrologic process. Then, we adopt the features of a topographic-information based on a hydrologic model, TOPMODEL (Beven and Kirkby, 1979), to enhance the representation of soil moisture movement in SWAT. Basically, the results of the study reveal, to some extent, the philosophy of modelling soil moisture movement in numerical models, which will be presented in the conference. Beven, K.J. and Kirkby, M.J., 1979. A physically based variable contributing area model of basin hydrology. Hydrol. Science Bulletin, 24: 43-69. Neitsch, S.L., Arnold, J.G., Kiniry, J.R., Williams, J.R. and King, K.W., 2005. Soil and Water Assessment Tool Theoretical Documentation, Grassland, soil and research service, Temple, TX.

  15. Animal models for osteoporosis

    NASA Technical Reports Server (NTRS)

    Turner, R. T.; Maran, A.; Lotinun, S.; Hefferan, T.; Evans, G. L.; Zhang, M.; Sibonga, J. D.

    2001-01-01

    Animal models will continue to be important tools in the quest to understand the contribution of specific genes to establishment of peak bone mass and optimal bone architecture, as well as the genetic basis for a predisposition toward accelerated bone loss in the presence of co-morbidity factors such as estrogen deficiency. Existing animal models will continue to be useful for modeling changes in bone metabolism and architecture induced by well-defined local and systemic factors. However, there is a critical unfulfilled need to develop and validate better animal models to allow fruitful investigation of the interaction of the multitude of factors which precipitate senile osteoporosis. Well characterized and validated animal models that can be recommended for investigation of the etiology, prevention and treatment of several forms of osteoporosis have been listed in Table 1. Also listed are models which are provisionally recommended. These latter models have potential but are inadequately characterized, deviate significantly from the human response, require careful choice of strain or age, or are not practical for most investigators to adopt. It cannot be stressed strongly enough that the enormous potential of laboratory animals as models for osteoporosis can only be realized if great care is taken in the choice of an appropriate species, age, experimental design, and measurements. Poor choices will results in misinterpretation of results which ultimately can bring harm to patients who suffer from osteoporosis by delaying advancement of knowledge.

  16. Modeling discrete and rhythmic movements through motor primitives: a review.

    PubMed

    Degallier, Sarah; Ijspeert, Auke

    2010-10-01

    Rhythmic and discrete movements are frequently considered separately in motor control, probably because different techniques are commonly used to study and model them. Yet the increasing interest in finding a comprehensive model for movement generation requires bridging the different perspectives arising from the study of those two types of movements. In this article, we consider discrete and rhythmic movements within the framework of motor primitives, i.e., of modular generation of movements. In this way we hope to gain an insight into the functional relationships between discrete and rhythmic movements and thus into a suitable representation for both of them. Within this framework we can define four possible categories of modeling for discrete and rhythmic movements depending on the required command signals and on the spinal processes involved in the generation of the movements. These categories are first discussed in terms of biological concepts such as force fields and central pattern generators and then illustrated by several mathematical models based on dynamical system theory. A discussion on the plausibility of theses models concludes the work.

  17. Control of movement initiation underlies the development of balance

    PubMed Central

    Ehrlich, David E.; Schoppik, David

    2017-01-01

    Summary Balance arises from the interplay of external forces acting on the body and internally generated movements. Many animal bodies are inherently unstable, necessitating corrective locomotion to maintain stability. Understanding how developing animals come to balance remains a challenge. Here we study the interplay between environment, sensation, and action as balance develops in larval zebrafish. We first model the physical forces that challenge underwater balance and experimentally confirm that larvae are subject to constant destabilization. Larvae propel in swim bouts that, we find, tend to stabilize the body. We confirm the relationship between locomotion and balance by changing larval body composition, exacerbating instability and eliciting more frequent swimming. Intriguingly, developing zebrafish come to control the initiation of locomotion, swimming preferentially when unstable, thus restoring preferred postures. To test the sufficiency of locomotor-driven stabilization and the developing control of movement timing, we incorporate both into a generative model of swimming. Simulated larvae recapitulate observed postures and movement timing across early development, but only when locomotor-driven stabilization and control of movement initiation are both utilized. We conclude the ability to move when unstable is the key developmental improvement to balance in larval zebrafish. Our work informs how emerging sensorimotor ability comes to impact how and why animals move when they do. PMID:28111151

  18. Should I Stay or Should I Go? A Habitat-Dependent Dispersal Kernel Improves Prediction of Movement

    PubMed Central

    Vinatier, Fabrice; Lescourret, Françoise; Duyck, Pierre-François; Martin, Olivier; Senoussi, Rachid; Tixier, Philippe

    2011-01-01

    The analysis of animal movement within different landscapes may increase our understanding of how landscape features affect the perceptual range of animals. Perceptual range is linked to movement probability of an animal via a dispersal kernel, the latter being generally considered as spatially invariant but could be spatially affected. We hypothesize that spatial plasticity of an animal's dispersal kernel could greatly modify its distribution in time and space. After radio tracking the movements of walking insects (Cosmopolites sordidus) in banana plantations, we considered the movements of individuals as states of a Markov chain whose transition probabilities depended on the habitat characteristics of current and target locations. Combining a likelihood procedure and pattern-oriented modelling, we tested the hypothesis that dispersal kernel depended on habitat features. Our results were consistent with the concept that animal dispersal kernel depends on habitat features. Recognizing the plasticity of animal movement probabilities will provide insight into landscape-level ecological processes. PMID:21765890

  19. Should I stay or should I go? A habitat-dependent dispersal kernel improves prediction of movement.

    PubMed

    Vinatier, Fabrice; Lescourret, Françoise; Duyck, Pierre-François; Martin, Olivier; Senoussi, Rachid; Tixier, Philippe

    2011-01-01

    The analysis of animal movement within different landscapes may increase our understanding of how landscape features affect the perceptual range of animals. Perceptual range is linked to movement probability of an animal via a dispersal kernel, the latter being generally considered as spatially invariant but could be spatially affected. We hypothesize that spatial plasticity of an animal's dispersal kernel could greatly modify its distribution in time and space. After radio tracking the movements of walking insects (Cosmopolites sordidus) in banana plantations, we considered the movements of individuals as states of a Markov chain whose transition probabilities depended on the habitat characteristics of current and target locations. Combining a likelihood procedure and pattern-oriented modelling, we tested the hypothesis that dispersal kernel depended on habitat features. Our results were consistent with the concept that animal dispersal kernel depends on habitat features. Recognizing the plasticity of animal movement probabilities will provide insight into landscape-level ecological processes.

  20. A general scaling law reveals why the largest animals are not the fastest.

    PubMed

    Hirt, Myriam R; Jetz, Walter; Rall, Björn C; Brose, Ulrich

    2017-08-01

    Speed is the fundamental constraint on animal movement, yet there is no general consensus on the determinants of maximum speed itself. Here, we provide a general scaling model of maximum speed with body mass, which holds across locomotion modes, ecosystem types and taxonomic groups. In contrast to traditional power-law scaling, we predict a hump-shaped relationship resulting from a finite acceleration time for animals, which explains why the largest animals are not the fastest. This model is strongly supported by extensive empirical data (474 species, with body masses ranging from 30 μg to 100 tonnes) from terrestrial as well as aquatic ecosystems. Our approach unravels a fundamental constraint on the upper limit of animal movement, thus enabling a better understanding of realized movement patterns in nature and their multifold ecological consequences.

  1. Animal models of sarcoidosis.

    PubMed

    Hu, Yijie; Yibrehu, Betel; Zabini, Diana; Kuebler, Wolfgang M

    2017-03-01

    Sarcoidosis is a debilitating, inflammatory, multiorgan, granulomatous disease of unknown cause, commonly affecting the lung. In contrast to other chronic lung diseases such as interstitial pulmonary fibrosis or pulmonary arterial hypertension, there is so far no widely accepted or implemented animal model for this disease. This has hampered our insights into the etiology of sarcoidosis, the mechanisms of its pathogenesis, the identification of new biomarkers and diagnostic tools and, last not least, the development and implementation of novel treatment strategies. Over past years, however, a number of new animal models have been described that may provide useful tools to fill these critical knowledge gaps. In this review, we therefore outline the present status quo for animal models of sarcoidosis, comparing their pros and cons with respect to their ability to mimic the etiological, clinical and histological hallmarks of human disease and discuss their applicability for future research. Overall, the recent surge in animal models has markedly expanded our options for translational research; however, given the relative early stage of most animal models for sarcoidosis, appropriate replication of etiological and histological features of clinical disease, reproducibility and usefulness in terms of identification of new therapeutic targets and biomarkers, and testing of new treatments should be prioritized when considering the refinement of existing or the development of new models.

  2. Animal models in burn research.

    PubMed

    Abdullahi, A; Amini-Nik, S; Jeschke, M G

    2014-09-01

    Burn injury is a severe form of trauma affecting more than 2 million people in North America each year. Burn trauma is not a single pathophysiological event but a devastating injury that causes structural and functional deficits in numerous organ systems. Due to its complexity and the involvement of multiple organs, in vitro experiments cannot capture this complexity nor address the pathophysiology. In the past two decades, a number of burn animal models have been developed to replicate the various aspects of burn injury, to elucidate the pathophysiology, and to explore potential treatment interventions. Understanding the advantages and limitations of these animal models is essential for the design and development of treatments that are clinically relevant to humans. This review aims to highlight the common animal models of burn injury in order to provide investigators with a better understanding of the benefits and limitations of these models for translational applications. While many animal models of burn exist, we limit our discussion to the skin healing of mouse, rat, and pig. Additionally, we briefly explain hypermetabolic characteristics of burn injury and the animal model utilized to study this phenomena. Finally, we discuss the economic costs associated with each of these models in order to guide decisions of choosing the appropriate animal model for burn research.

  3. Modelling Fine Scale Movement Corridors for the Tricarinate Hill Turtle

    NASA Astrophysics Data System (ADS)

    Mondal, I.; Kumar, R. S.; Habib, B.; Talukdar, G.

    2016-06-01

    Habitat loss and the destruction of habitat connectivity can lead to species extinction by isolation of population. Identifying important habitat corridors to enhance habitat connectivity is imperative for species conservation by preserving dispersal pattern to maintain genetic diversity. Circuit theory is a novel tool to model habitat connectivity as it considers habitat as an electronic circuit board and species movement as a certain amount of current moving around through different resistors in the circuit. Most studies involving circuit theory have been carried out at small scales on large ranging animals like wolves or pumas, and more recently on tigers. This calls for a study that tests circuit theory at a large scale to model micro-scale habitat connectivity. The present study on a small South-Asian geoemydid, the Tricarinate Hill-turtle (Melanochelys tricarinata), focuses on habitat connectivity at a very fine scale. The Tricarinate has a small body size (carapace length: 127-175 mm) and home range (8000-15000 m2), with very specific habitat requirements and movement patterns. We used very high resolution Worldview satellite data and extensive field observations to derive a model of landscape permeability at 1 : 2,000 scale to suit the target species. Circuit theory was applied to model potential corridors between core habitat patches for the Tricarinate Hill-turtle. The modelled corridors were validated by extensive ground tracking data collected using thread spool technique and found to be functional. Therefore, circuit theory is a promising tool for accurately identifying corridors, to aid in habitat studies of small species.

  4. Multi-hierarchical movements in self-avoiding walks

    NASA Astrophysics Data System (ADS)

    Sakiyama, Tomoko; Gunji, Yukio-Pegio

    2017-07-01

    A self-avoiding walk (SAW) is a series of moves on a lattice that visit the same place only once. Several studies reported that repellent reactions of foragers to previously visited sites induced power-law tailed SAWs in animals. In this paper, we show that modelling the agent's multi-avoidance reactions to its trails enables it to show ballistic movements which result in heavy-tailed movements. There is no literature showing emergent ballistic movements in SAWs. While following SAWs, the agent in my model changed its reactions to marked patches (visited sites) by considering global trail patterns based on local trail patterns when the agent was surrounded by previously visited sites. As a result, we succeeded in producing ballistic walks by the agents which exhibited emergent power-law tailed movements.

  5. Does movement behaviour predict population densities? A test with 25 butterfly species.

    PubMed

    Schultz, Cheryl B; Pe'er, B Guy; Damiani, Christine; Brown, Leone; Crone, Elizabeth E

    2017-03-01

    Diffusion, which approximates a correlated random walk, has been used by ecologists to describe movement, and forms the basis for many theoretical models. However, it is often criticized as too simple a model to describe animal movement in real populations. We test a key prediction of diffusion models, namely, that animals should be more abundant in land cover classes through which they move more slowly. This relationship between density and diffusion has rarely been tested across multiple species within a given landscape. We estimated diffusion rates and corresponding densities of 25 Israeli butterfly species from flight path data and visual surveys. The data were collected across 19 sites in heterogeneous landscapes with four land cover classes: semi-natural habitat, olive groves, wheat fields and field margins. As expected from theory, species tended to have higher densities in land cover classes through which they moved more slowly and lower densities in land cover classes through which they moved more quickly. Two components of movement (move length and turning angle) were not associated with density, nor was expected net squared displacement. Move time, however, was associated with density, and animals spent more time per move step in areas with higher density. The broad association we document between movement behaviour and density suggests that diffusion is a good first approximation of movement in butterflies. Moreover, our analyses demonstrate that dispersal is not a species-invariant trait, but rather one that depends on landscape context. Thus, land cover classes with high diffusion rates are likely to have low densities and be effective conduits for movement. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

  6. Prediction of Pig Trade Movements in Different European Production Systems Using Exponential Random Graph Models.

    PubMed

    Relun, Anne; Grosbois, Vladimir; Alexandrov, Tsviatko; Sánchez-Vizcaíno, Jose M; Waret-Szkuta, Agnes; Molia, Sophie; Etter, Eric Marcel Charles; Martínez-López, Beatriz

    2017-01-01

    In most European countries, data regarding movements of live animals are routinely collected and can greatly aid predictive epidemic modeling. However, the use of complete movements' dataset to conduct policy-relevant predictions has been so far limited by the massive amount of data that have to be processed (e.g., in intensive commercial systems) or the restricted availability of timely and updated records on animal movements (e.g., in areas where small-scale or extensive production is predominant). The aim of this study was to use exponential random graph models (ERGMs) to reproduce, understand, and predict pig trade networks in different European production systems. Three trade networks were built by aggregating movements of pig batches among premises (farms and trade operators) over 2011 in Bulgaria, Extremadura (Spain), and Côtes-d'Armor (France), where small-scale, extensive, and intensive pig production are predominant, respectively. Three ERGMs were fitted to each network with various demographic and geographic attributes of the nodes as well as six internal network configurations. Several statistical and graphical diagnostic methods were applied to assess the goodness of fit of the models. For all systems, both exogenous (attribute-based) and endogenous (network-based) processes appeared to govern the structure of pig trade network, and neither alone were capable of capturing all aspects of the network structure. Geographic mixing patterns strongly structured pig trade organization in the small-scale production system, whereas belonging to the same company or keeping pigs in the same housing system appeared to be key drivers of pig trade, in intensive and extensive production systems, respectively. Heterogeneous mixing between types of production also explained a part of network structure, whichever production system considered. Limited information is thus needed to capture most of the global structure of pig trade networks. Such findings will be useful

  7. Logical fallacies in animal model research.

    PubMed

    Sjoberg, Espen A

    2017-02-15

    Animal models of human behavioural deficits involve conducting experiments on animals with the hope of gaining new knowledge that can be applied to humans. This paper aims to address risks, biases, and fallacies associated with drawing conclusions when conducting experiments on animals, with focus on animal models of mental illness. Researchers using animal models are susceptible to a fallacy known as false analogy, where inferences based on assumptions of similarities between animals and humans can potentially lead to an incorrect conclusion. There is also a risk of false positive results when evaluating the validity of a putative animal model, particularly if the experiment is not conducted double-blind. It is further argued that animal model experiments are reconstructions of human experiments, and not replications per se, because the animals cannot follow instructions. This leads to an experimental setup that is altered to accommodate the animals, and typically involves a smaller sample size than a human experiment. Researchers on animal models of human behaviour should increase focus on mechanistic validity in order to ensure that the underlying causal mechanisms driving the behaviour are the same, as relying on face validity makes the model susceptible to logical fallacies and a higher risk of Type 1 errors. We discuss measures to reduce bias and risk of making logical fallacies in animal research, and provide a guideline that researchers can follow to increase the rigour of their experiments.

  8. Animal Models in Burn Research

    PubMed Central

    Abdullahi, A.; Amini-Nik, S.; Jeschke, M.G

    2014-01-01

    Burn injury is a severe form of trauma affecting more than two million people in North America each year. Burn trauma is not a single pathophysiological event but a devastating injury that causes structural and functional deficits in numerous organ systems. Due to its complexity and the involvement of multiple organs, in vitro experiments cannot capture this complexity nor address the pathophysiology. In the past two decades, a number of burn animal models have been developed to replicate the various aspects of burn injury; to elucidate the pathophysiology and explore potential treatment interventions. Understanding the advantages and limitations of these animal models is essential for the design and development of treatments that are clinically relevant to humans. This review paper aims to highlight the common animal models of burn injury in order to provide investigators with a better understanding of the benefits and limitations of these models for translational applications. While many animal models of burn exist, we limit our discussion to the skin healing of mouse, rat, and pig. Additionally, we briefly explain hypermetabolic characteristics of burn injury and the animal model utilized to study this phenomena. Finally, we discuss the economic costs associated with each of these models in order to guide decisions of choosing the appropriate animal model for burn research. PMID:24714880

  9. Size Matters: Observed and Modeled Camouflage Response of European Cuttlefish (Sepia officinalis) to Different Substrate Patch Sizes during Movement

    PubMed Central

    Josef, Noam; Berenshtein, Igal; Rousseau, Meghan; Scata, Gabriella; Fiorito, Graziano; Shashar, Nadav

    2017-01-01

    Camouflage is common throughout the phylogenetic tree and is largely used to minimize detection by predator or prey. Cephalopods, and in particular Sepia officinalis cuttlefish, are common models for camouflage studies. Predator avoidance behavior is particularly important in this group of soft-bodied animals that lack significant physical defenses. While previous studies have suggested that immobile cephalopods selectively camouflage to objects in their immediate surroundings, the camouflage characteristics of cuttlefish during movement are largely unknown. In a heterogenic environment, the visual background and substrate feature changes quickly as the animal swim across it, wherein substrate patch is a distinctive and high contrast patch of substrate in the animal's trajectory. In the current study, we examine the effect of substrate patch size on cuttlefish camouflage, and specifically the minimal size of an object for eliciting intensity matching response while moving. Our results indicated that substrate patch size has a positive effect on animal's reflectance change, and that the threshold patch size resulting in camouflage response falls between 10 and 19 cm (width). These observations suggest that the animal's length (7.2–12.3 cm mantle length in our case) serves as a possible threshold filter below which objects are considered irrelevant for camouflage, reducing the frequency of reflectance changes—which may lead to detection. Accordingly, we have constructed a computational model capturing the main features of the observed camouflaging behavior, provided for cephalopod camouflage during movement. PMID:28144221

  10. Size Matters: Observed and Modeled Camouflage Response of European Cuttlefish (Sepia officinalis) to Different Substrate Patch Sizes during Movement.

    PubMed

    Josef, Noam; Berenshtein, Igal; Rousseau, Meghan; Scata, Gabriella; Fiorito, Graziano; Shashar, Nadav

    2016-01-01

    Camouflage is common throughout the phylogenetic tree and is largely used to minimize detection by predator or prey. Cephalopods, and in particular Sepia officinalis cuttlefish, are common models for camouflage studies. Predator avoidance behavior is particularly important in this group of soft-bodied animals that lack significant physical defenses. While previous studies have suggested that immobile cephalopods selectively camouflage to objects in their immediate surroundings, the camouflage characteristics of cuttlefish during movement are largely unknown. In a heterogenic environment, the visual background and substrate feature changes quickly as the animal swim across it, wherein substrate patch is a distinctive and high contrast patch of substrate in the animal's trajectory. In the current study, we examine the effect of substrate patch size on cuttlefish camouflage, and specifically the minimal size of an object for eliciting intensity matching response while moving. Our results indicated that substrate patch size has a positive effect on animal's reflectance change, and that the threshold patch size resulting in camouflage response falls between 10 and 19 cm (width). These observations suggest that the animal's length (7.2-12.3 cm mantle length in our case) serves as a possible threshold filter below which objects are considered irrelevant for camouflage, reducing the frequency of reflectance changes-which may lead to detection. Accordingly, we have constructed a computational model capturing the main features of the observed camouflaging behavior, provided for cephalopod camouflage during movement.

  11. From sensor data to animal behaviour: an oystercatcher example.

    PubMed

    Shamoun-Baranes, Judy; Bom, Roeland; van Loon, E Emiel; Ens, Bruno J; Oosterbeek, Kees; Bouten, Willem

    2012-01-01

    Animal-borne sensors enable researchers to remotely track animals, their physiological state and body movements. Accelerometers, for example, have been used in several studies to measure body movement, posture, and energy expenditure, although predominantly in marine animals. In many studies, behaviour is often inferred from expert interpretation of sensor data and not validated with direct observations of the animal. The aim of this study was to derive models that could be used to classify oystercatcher (Haematopus ostralegus) behaviour based on sensor data. We measured the location, speed, and tri-axial acceleration of three oystercatchers using a flexible GPS tracking system and conducted simultaneous visual observations of the behaviour of these birds in their natural environment. We then used these data to develop three supervised classification trees of behaviour and finally applied one of the models to calculate time-activity budgets. The model based on accelerometer data developed to classify three behaviours (fly, terrestrial locomotion, and no movement) was much more accurate (cross-validation error = 0.14) than the model based on GPS-speed alone (cross-validation error = 0.35). The most parsimonious acceleration model designed to classify eight behaviours could distinguish five: fly, forage, body care, stand, and sit (cross-validation error = 0.28); other behaviours that were observed, such as aggression or handling of prey, could not be distinguished. Model limitations and potential improvements are discussed. The workflow design presented in this study can facilitate model development, be adapted to a wide range of species, and together with the appropriate measurements, can foster the study of behaviour and habitat use of free living animals throughout their annual routine.

  12. Modeling loggerhead turtle movement in the Mediterranean: importance of body size and oceanography.

    PubMed

    Eckert, Scott A; Moore, Jeffrey E; Dunn, Daniel C; van Buiten, Ricardo Sagarminaga; Eckert, Karen L; Halpin, Patrick N

    2008-03-01

    Adapting state-space models (SSMs) to telemetry data has been helpful for dealing with location error and for modeling animal movements. We used a combination of two hierarchical Bayesian SSMs to estimate movement pathways from Argos satellite-tag data for 15 juvenile loggerhead turtles (Caretta caretta) in the western Mediterranean Sea, and to probabilistically assign locations to one of two behavioral movement types and relate those behaviors to environmental features. A Monte Carlo procedure helped propagate location uncertainty from the first SSM into the estimation of behavioral states and environment--behavior relationships in the second SSM. Turtles using oceanic habitats of the Balearic Sea (n = 9 turtles) within the western Mediterranean were more likely to exhibit "intensive search" behavior as might occur during foraging, but only larger turtles responded to variations in sea-surface height. This suggests that they were better able than smaller turtles to cue on environmental features that concentrate prey resources or were more dependent on high-quality feeding areas. These findings stress the importance of individual heterogeneity in the analysis of movement behavior and, taken in concert with descriptive studies of Pacific loggerheads, suggest that directed movements toward patchy ephemeral resources may be a general property of larger juvenile loggerheads in different populations. We discovered size-based variation in loggerhead distribution and documented use of the western Mediterranean Sea by turtles larger than previously thought to occur there. With one exception, only individuals > 57 cm curved carapace length used the most westerly basin in the Mediterranean (western Alborán Sea). These observations shed new light on loggerhead migration phenology.

  13. Animal models of transcranial direct current stimulation: Methods and mechanisms.

    PubMed

    Jackson, Mark P; Rahman, Asif; Lafon, Belen; Kronberg, Gregory; Ling, Doris; Parra, Lucas C; Bikson, Marom

    2016-11-01

    complexity of normal and pathological brain function, and how recent studies have already indicated more sophisticated approaches are necessary. One tDCS theory regarding "functional targeting" suggests the specificity of tDCS effects are possible by modulating ongoing function (plasticity). Use of animal models of disease are summarized including pain, movement disorders, stroke, and epilepsy. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  14. Animal Models of transcranial Direct Current Stimulation: Methods and Mechanisms

    PubMed Central

    Jackson, Mark P.; Rahman, Asif; Lafon, Belen; Kronberg, Gregory; Ling, Doris; Parra, Lucas C.; Bikson, Marom

    2016-01-01

    complexity of normal and pathological brain function, and how recent studies have already indicated more sophisticated approaches are necessary. One tDCS theory regarding “functional targeting” suggests the specificity of tDCS effects are possible by modulating ongoing function (plasticity). Use of animal models of disease are summarized including pain, movement disorders, stroke, and epilepsy. PMID:27693941

  15. Animal models of cerebral ischemia

    NASA Astrophysics Data System (ADS)

    Khodanovich, M. Yu.; Kisel, A. A.

    2015-11-01

    Cerebral ischemia remains one of the most frequent causes of death and disability worldwide. Animal models are necessary to understand complex molecular mechanisms of brain damage as well as for the development of new therapies for stroke. This review considers a certain range of animal models of cerebral ischemia, including several types of focal and global ischemia. Since animal models vary in specificity for the human disease which they reproduce, the complexity of surgery, infarct size, reliability of reproduction for statistical analysis, and adequate models need to be chosen according to the aim of a study. The reproduction of a particular animal model needs to be evaluated using appropriate tools, including the behavioral assessment of injury and non-invasive and post-mortem control of brain damage. These problems also have been summarized in the review.

  16. Tracking boundary movement and exterior shape modelling in lung EIT imaging.

    PubMed

    Biguri, A; Grychtol, B; Adler, A; Soleimani, M

    2015-06-01

    Electrical impedance tomography (EIT) has shown significant promise for lung imaging. One key challenge for EIT in this application is the movement of electrodes during breathing, which introduces artefacts in reconstructed images. Various approaches have been proposed to compensate for electrode movement, but no comparison of these approaches is available. This paper analyses boundary model mismatch and electrode movement in lung EIT. The aim is to evaluate the extent to which various algorithms tolerate movement, and to determine if a patient specific model is required for EIT lung imaging. Movement data are simulated from a CT-based model, and image analysis is performed using quantitative figures of merit. The electrode movement is modelled based on expected values of chest movement and an extended Jacobian method is proposed to make use of exterior boundary tracking. Results show that a dynamical boundary tracking is the most robust method against any movement, but is computationally more expensive. Simultaneous electrode movement and conductivity reconstruction algorithms show increased robustness compared to only conductivity reconstruction. The results of this comparative study can help develop a better understanding of the impact of shape model mismatch and electrode movement in lung EIT.

  17. REPETETIVE HINDLIMB MOVEMENT USING INTERMITTENT ADAPTIVE NEUROMUSCULAR ELECTRICAL STIMULATION IN AN INCOMPLETE SPINAL CORD INJURY RODENT MODEL

    PubMed Central

    Fairchild, Mallika; Kim, Seung-Jae; Iarkov, Alex; Abbas, James J.; Jung, Ranu

    2010-01-01

    The long-term objective of this work is to understand the mechanisms by which electrical stimulation based movement therapies may harness neural plasticity to accelerate and enhance sensorimotor recovery after incomplete spinal cord injury (iSCI). An adaptive neuromuscular electrical stimulation (aNMES) paradigm was implemented in adult Long Evans rats with thoracic contusion injury (T8 vertebral level, 155±2 Kdyne). In lengthy sessions with lightly anesthetized animals, hip flexor and extensor muscles were stimulated using an aNMES control system in order to generate desired hip movements. The aNMES control system, which used a pattern generator/pattern shaper structure, adjusted pulse amplitude to modulate muscle force in order to control hip movement. An intermittent stimulation paradigm was used (5-cycles/set; 20-second rest between sets; 100 sets). In each cycle, hip rotation caused the foot plantar surface to contact a stationary brush for appropriately timed cutaneous input. Sessions were repeated over several days while the animals recovered from injury. Results indicated that aNMES automatically and reliably tracked the desired hip trajectory with low error and maintained range of motion with only gradual increase in stimulation during the long sessions. Intermittent aNMES thus accounted for the numerous factors that can influence the response to NMES: electrode stability, excitability of spinal neural circuitry, non-linear muscle recruitment, fatigue, spinal reflexes due to cutaneous input, and the endogenous recovery of the animals. This novel aNMES application in the iSCI rodent model can thus be used in chronic stimulation studies to investigate the mechanisms of neuroplasticity targeted by NMES-based repetitive movement therapy. PMID:20206164

  18. 9 CFR 91.4 - Other movements and conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Other movements and conditions. 91.4 Section 91.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... HANDLING OF LIVESTOCK FOR EXPORTATION General Provisions § 91.4 Other movements and conditions. The...

  19. 9 CFR 85.4 - Interstate movement of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement of livestock. 85.4 Section 85.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... Interstate movement of livestock. (a) Livestock showing clinical evidence of pseudorabies shall not be moved...

  20. Animal models in myopia research.

    PubMed

    Schaeffel, Frank; Feldkaemper, Marita

    2015-11-01

    Our current understanding of the development of refractive errors, in particular myopia, would be substantially limited had Wiesel and Raviola not discovered by accident that monkeys develop axial myopia as a result of deprivation of form vision. Similarly, if Josh Wallman and colleagues had not found that simple plastic goggles attached to the chicken eye generate large amounts of myopia, the chicken model would perhaps not have become such an important animal model. Contrary to previous assumptions about the mechanisms of myopia, these animal models suggested that eye growth is visually controlled locally by the retina, that an afferent connection to the brain is not essential and that emmetropisation uses more sophisticated cues than just the magnitude of retinal blur. While animal models have shown that the retina can determine the sign of defocus, the underlying mechanism is still not entirely clear. Animal models have also provided knowledge about the biochemical nature of the signal cascade converting the output of retinal image processing to changes in choroidal thickness and scleral growth; however, a critical question was, and still is, can the results from animal models be applied to myopia in children? While the basic findings from chickens appear applicable to monkeys, some fundamental questions remain. If eye growth is guided by visual feedback, why is myopic development not self-limiting? Why does undercorrection not arrest myopic progression even though positive lenses induce myopic defocus, which leads to the development of hyperopia in emmetropic animals? Why do some spectacle or contact lens designs reduce myopic progression and others not? It appears that some major differences exist between animals reared with imposed defocus and children treated with various optical corrections, although without the basic knowledge obtained from animal models, we would be lost in an abundance of untestable hypotheses concerning human myopia. © 2015 Optometry

  1. 9 CFR 73.1 - Interstate movement prohibited.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement prohibited. 73.1... § 73.1 Interstate movement prohibited. (a) Cattle affected with scabies. No cattle affected with... movement, were affected with or exposed to scabies shall be shipped, trailed, driven, or otherwise moved...

  2. 9 CFR 85.9 - Other interstate movements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Other interstate movements. 85.9... Other interstate movements. The Administrator may, upon request in specific cases, permit the interstate movement of livestock not otherwise provided for in this part under such conditions as he may prescribe to...

  3. Using Machine Learning to Predict Swine Movements within a Regional Program to Improve Control of Infectious Diseases in the US.

    PubMed

    Valdes-Donoso, Pablo; VanderWaal, Kimberly; Jarvis, Lovell S; Wayne, Spencer R; Perez, Andres M

    2017-01-01

    Between-farm animal movement is one of the most important factors influencing the spread of infectious diseases in food animals, including in the US swine industry. Understanding the structural network of contacts in a food animal industry is prerequisite to planning for efficient production strategies and for effective disease control measures. Unfortunately, data regarding between-farm animal movements in the US are not systematically collected and thus, such information is often unavailable. In this paper, we develop a procedure to replicate the structure of a network, making use of partial data available, and subsequently use the model developed to predict animal movements among sites in 34 Minnesota counties. First, we summarized two networks of swine producing facilities in Minnesota, then we used a machine learning technique referred to as random forest, an ensemble of independent classification trees, to estimate the probability of pig movements between farms and/or markets sites located in two counties in Minnesota. The model was calibrated and tested by comparing predicted data and observed data in those two counties for which data were available. Finally, the model was used to predict animal movements in sites located across 34 Minnesota counties. Variables that were important in predicting pig movements included between-site distance, ownership, and production type of the sending and receiving farms and/or markets. Using a weighted-kernel approach to describe spatial variation in the centrality measures of the predicted network, we showed that the south-central region of the study area exhibited high aggregation of predicted pig movements. Our results show an overlap with the distribution of outbreaks of porcine reproductive and respiratory syndrome, which is believed to be transmitted, at least in part, though animal movements. While the correspondence of movements and disease is not a causal test, it suggests that the predicted network may approximate

  4. Animal models in peritoneal dialysis.

    PubMed

    Nikitidou, Olga; Peppa, Vasiliki I; Leivaditis, Konstantinos; Eleftheriadis, Theodoros; Zarogiannis, Sotirios G; Liakopoulos, Vassilios

    2015-01-01

    Peritoneal dialysis (PD) has been extensively used over the past years as a method of kidney replacement therapy for patients with end stage renal disease (ESRD). In an attempt to better understand the properties of the peritoneal membrane and the mechanisms involved in major complications associated with PD, such as inflammation, peritonitis and peritoneal injury, both in vivo and ex vivo animal models have been used. The aim of the present review is to briefly describe the animal models that have been used, and comment on the main problems encountered while working with these models. Moreover, the differences characterizing these animal models, as well as, the differences with humans are highlighted. Finally, it is suggested that the use of standardized protocols is a necessity in order to take full advantage of animal models, extrapolate their results in humans, overcome the problems related to PD and help promote its use.

  5. Temporal segmentation of animal trajectories informed by habitat use

    USGS Publications Warehouse

    van Toor, Marielle L.; Newman, Scott H.; Takekawa, John Y.; Wegmann, Martin; Safi, Kamran

    2016-01-01

    Most animals live in seasonal environments and experience very different conditions throughout the year. Behavioral strategies like migration, hibernation, and a life cycle adapted to the local seasonality help to cope with fluctuations in environmental conditions. Thus, how an individual utilizes the environment depends both on the current availability of habitat and the behavioral prerequisites of the individual at that time. While the increasing availability and richness of animal movement data has facilitated the development of algorithms that classify behavior by movement geometry, changes in the environmental correlates of animal movement have so far not been exploited for a behavioral annotation. Here, we suggest a method that uses these changes in individual–environment associations to divide animal location data into segments of higher ecological coherence, which we term niche segmentation. We use time series of random forest models to evaluate the transferability of habitat use over time to cluster observational data accordingly. We show that our method is able to identify relevant changes in habitat use corresponding to both changes in the availability of habitat and how it was used using simulated data, and apply our method to a tracking data set of common teal (Anas crecca). The niche segmentation proved to be robust, and segmented habitat suitability outperformed models neglecting the temporal dynamics of habitat use. Overall, we show that it is possible to classify animal trajectories based on changes of habitat use similar to geometric segmentation algorithms. We conclude that such an environmentally informed classification of animal trajectories can provide new insights into an individuals' behavior and enables us to make sensible predictions of how suitable areas might be connected by movement in space and time.

  6. Overview of Animal Models of Obesity

    PubMed Central

    Lutz, Thomas A.; Woods, Stephen C.

    2012-01-01

    This is a review of animal models of obesity currently used in research. We have focused upon more commonly utilized models since there are far too many newly created models to consider, especially those caused by selective molecular genetic approaches modifying one or more genes in specific populations of cells. Further, we will not discuss the generation and use of inducible transgenic animals (induced knock-out or knock-in) even though they often bear significant advantages compared to traditional transgenic animals; influences of the genetic modification during the development of the animals can be minimized. The number of these animal models is simply too large to be covered in this chapter. PMID:22948848

  7. A search theory model of patch-to-patch forager movement with application to pollinator-mediated gene flow.

    PubMed

    Hoyle, Martin; Cresswell, James E

    2007-09-07

    We present a spatially implicit analytical model of forager movement, designed to address a simple scenario common in nature. We assume minimal depression of patch resources, and discrete foraging bouts, during which foragers fill to capacity. The model is particularly suitable for foragers that search systematically, foragers that deplete resources in a patch only incrementally, and for sit-and-wait foragers, where harvesting does not affect the rate of arrival of forage. Drawing on the theory of job search from microeconomics, we estimate the expected number of patches visited as a function of just two variables: the coefficient of variation of the rate of energy gain among patches, and the ratio of the expected time exploiting a randomly chosen patch and the expected time travelling between patches. We then consider the forager as a pollinator and apply our model to estimate gene flow. Under model assumptions, an upper bound for animal-mediated gene flow between natural plant populations is approximately proportional to the probability that the animal rejects a plant population. In addition, an upper bound for animal-mediated gene flow in any animal-pollinated agricultural crop from a genetically modified (GM) to a non-GM field is approximately proportional to the proportion of fields that are GM and the probability that the animal rejects a field.

  8. Modelling eye movements in a categorical search task

    PubMed Central

    Zelinsky, Gregory J.; Adeli, Hossein; Peng, Yifan; Samaras, Dimitris

    2013-01-01

    We introduce a model of eye movements during categorical search, the task of finding and recognizing categorically defined targets. It extends a previous model of eye movements during search (target acquisition model, TAM) by using distances from an support vector machine classification boundary to create probability maps indicating pixel-by-pixel evidence for the target category in search images. Other additions include functionality enabling target-absent searches, and a fixation-based blurring of the search images now based on a mapping between visual and collicular space. We tested this model on images from a previously conducted variable set-size (6/13/20) present/absent search experiment where participants searched for categorically defined teddy bear targets among random category distractors. The model not only captured target-present/absent set-size effects, but also accurately predicted for all conditions the numbers of fixations made prior to search judgements. It also predicted the percentages of first eye movements during search landing on targets, a conservative measure of search guidance. Effects of set size on false negative and false positive errors were also captured, but error rates in general were overestimated. We conclude that visual features discriminating a target category from non-targets can be learned and used to guide eye movements during categorical search. PMID:24018720

  9. Ophiuroid robot that self-organizes periodic and non-periodic arm movements.

    PubMed

    Kano, Takeshi; Suzuki, Shota; Watanabe, Wataru; Ishiguro, Akio

    2012-09-01

    Autonomous decentralized control is a key concept for understanding the mechanism underlying adaptive and versatile locomotion of animals. Although the design of an autonomous decentralized control system that ensures adaptability by using coupled oscillators has been proposed previously, it cannot comprehensively reproduce the versatility of animal behaviour. To tackle this problem, we focus on using ophiuroids as a simple model that exhibits versatile locomotion including periodic and non-periodic arm movements. Our existing model for ophiuroid locomotion uses an active rotator model that describes both oscillatory and excitatory properties. In this communication, we develop an ophiuroid robot to confirm the validity of this proposed model in the real world. We show that the robot travels by successfully coordinating periodic and non-periodic arm movements in response to external stimuli.

  10. Modeling movement and fidelity of American black ducks

    USGS Publications Warehouse

    Zimpfer, N.L.; Conroy, M.J.

    2006-01-01

    Spatial relationships among stocks of breeding waterfowl can be an important component of harvest management. Prediction and optimal harvest management under adaptive harvest management (AHM) requires information on the spatial relationships among breeding populations (fidelity and inter-year exchange), as well as rates of movements from breeding to harvest regions. We used band-recovery data to develop a model to estimate probabilities of movement for American black ducks (Anas rubripes) among 3 Canadian breeding strata and 6 harvest regions (3 in Canada, and 3 in the United States) over the period 1965-1998. Model selection criteria suggested that models containing area-, year-, and age-specific recovery rates with area- and sex-specific movement rates were the best for modeling movement. Movement by males to southern harvest areas was variable depending on the originating area. Males from the western breeding area predominantly moved to the Mississippi Flyway or southern Atlantic Flyway (??ij = 0.353, SE = 0.0187 and ??ij = 0.473, SE = 0.037, respectively), whereas males that originated in the eastern and central breeding strata moved to the northern Atlantic flyway (??ij = 0.842, SE = 0.010 and ??ij = 0.578, SE = 0.0222, respectively). We used combined recoveries and recaptures in Program MARK to estimate fidelity to the 3 Canadian breeding strata. Information criteria identified a model containing sex- and age-specific fidelity for black ducks. Estimates of fidelity were 0.9695 (SE = 0.0249) and 0.9554 (SE = 0.0434) for adult males and females, respectively. Estimates of fidelity for juveniles were slightly lower at 0.9210 (SE = 0.0931) and 0.8870 (SE = 0.0475) for males and females, respectively. These models have application to the development of spatially stratified black duck harvest management models for use in AHM.

  11. [Role of stress in depression insomnia and sleep characteristics of commonly used animal stress models].

    PubMed

    Li, Yi-Ying; Hu, Zhen-Zhen; Huang, Zhi-Li; Yang, Su-Rong

    2012-01-01

    Depression and insomnia are intimately related. Depressed patients usually manifest sleep discontinuity and early awakening, reduced or no slow wave sleep (SWS) and shortened latency of rapid eye movement (REM) sleep. These sleep abnormalities are very similar to those caused by over activated hypothalamic-pituitary-adrenal (HPA) axis with stress. Therefore, the animal models developed by post-traumatic stress disorder or chronic unpredictable mild stress could be used to evaluate drugs which have effects of both anti-depression and improvement of sleep quality, and to provide a more reliable platform for further studis on the mechanisms of depression and accompanied insomnia. This review mainly focuses on the typical features of sleep disturbance of depression, possible pathophysiological mechanisms, establishment of animal stress models and analysis of their abnormal sleep characteristics.

  12. Modeling Caribou Movements: Seasonal Ranges and Migration Routes of the Central Arctic Herd

    PubMed Central

    Nicholson, Kerry L.; Arthur, Stephen M.; Horne, Jon S.; Garton, Edward O.; Del Vecchio, Patricia A.

    2016-01-01

    Migration is an important component of the life history of many animals, but persistence of large-scale terrestrial migrations is being challenged by environmental changes that fragment habitats and create obstacles to animal movements. In northern Alaska, the Central Arctic herd (CAH) of barren-ground caribou (Rangifer tarandus granti) is known to migrate over large distances, but the herd’s seasonal distributions and migratory movements are not well documented. From 2003–2007, we used GPS radio-collars to determine seasonal ranges and migration routes of 54 female caribou from the CAH. We calculated Brownian bridges to model fall and spring migrations for each year and used the mean of these over all 4 years to identify areas that were used repeatedly. Annual estimates of sizes of seasonal ranges determined by 90% fixed kernel utilization distributions were similar between summer and winter (X̅ = 27,929 SE = 1,064 and X̅ = 26,585 SE = 4912 km2, respectively). Overlap between consecutive summer and winter ranges varied from 3.3–18.3%. Percent overlap between summer ranges used during consecutive years (X̅ = 62.4% SE = 3.7%) was higher than for winter ranges (X̅ = 42.8% SE = 5.9%). Caribou used multiple migration routes each year, but some areas were used by caribou during all years, suggesting that these areas should be managed to allow for continued utilization by caribou. Restoring migration routes after they have been disturbed or fragmented is challenging. However, prior knowledge of movements and threats may facilitate maintenance of migratory paths and seasonal ranges necessary for long-term persistence of migratory species. PMID:27045587

  13. Heterogeneous movement of insectivorous Amazonian birds through primary and secondary forest: A case study using multistate models with radiotelemetry data

    Treesearch

    Luke L. Powell; Jared D. Wolfe; Erik I. Johnson; James E. Hines; James D. Nichols; Philip C Stouffer

    2015-01-01

    Given rates of deforestation, disturbance, and secondary forest accumulation in tropical rainforests, there is a great need to quantify habitat use and movement among different habitats. This need is particularly pronounced for animals most sensitive to disturbance, such as insectivorous understory birds. Here we use multistate capture–recapture models with...

  14. The utility of modeling word identification from visual input within models of eye movements in reading

    PubMed Central

    Bicknell, Klinton; Levy, Roger

    2012-01-01

    Decades of empirical work have shown that a range of eye movement phenomena in reading are sensitive to the details of the process of word identification. Despite this, major models of eye movement control in reading do not explicitly model word identification from visual input. This paper presents a argument for developing models of eye movements that do include detailed models of word identification. Specifically, we argue that insights into eye movement behavior can be gained by understanding which phenomena naturally arise from an account in which the eyes move for efficient word identification, and that one important use of such models is to test which eye movement phenomena can be understood this way. As an extended case study, we present evidence from an extension of a previous model of eye movement control in reading that does explicitly model word identification from visual input, Mr. Chips (Legge, Klitz, & Tjan, 1997), to test two proposals for the effect of using linguistic context on reading efficiency. PMID:23074362

  15. Covering Ground: Movement Patterns and Random Walk Behavior in Aquilonastra anomala Sea Stars.

    PubMed

    Lohmann, Amanda C; Evangelista, Dennis; Waldrop, Lindsay D; Mah, Christopher L; Hedrick, Tyson L

    2016-10-01

    The paths animals take while moving through their environments affect their likelihood of encountering food and other resources; thus, models of foraging behavior abound. To collect movement data appropriate for comparison with these models, we used time-lapse photography to track movements of a small, hardy, and easy-to-obtain organism, Aquilonastra anomala sea stars. We recorded the sea stars in a tank over many hours, with and without a food cue. With food present, they covered less distance, as predicted by theory; this strategy would allow them to remain near food. We then compared the paths of the sea stars to three common models of animal movement: Brownian motion, Lévy walks, and correlated random walks; we found that the sea stars' movements most closely resembled a correlated random walk. Additionally, we compared the search performance of models of Brownian motion, a Lévy walk, and a correlated random walk to that of a model based on the sea stars' movements. We found that the behavior of the modeled sea star walk was similar to that of the modeled correlated random walk and the Brownian motion model, but that the sea star walk was slightly more likely than the other walks to find targets at intermediate distances. While organisms are unlikely to follow an idealized random walk in all details, our data suggest that comparing the effectiveness of an organism's paths to those from theory can give insight into the organism's actual movement strategy. Finally, automated optical tracking of invertebrates proved feasible, and A. anomala was revealed to be a tractable, 2D-movement study system.

  16. Using dynamic Brownian bridge movement modelling to measure temporal patterns of habitat selection.

    PubMed

    Byrne, Michael E; Clint McCoy, J; Hinton, Joseph W; Chamberlain, Michael J; Collier, Bret A

    2014-09-01

    Accurately describing animal space use is vital to understanding how wildlife use habitat. Improvements in GPS technology continue to facilitate collection of telemetry data at high spatial and temporal resolutions. Application of the recently introduced dynamic Brownian bridge movement model (dBBMM) to such data is promising as the method explicitly incorporates the behavioural heterogeneity of a movement path into the estimated utilization distribution (UD). Utilization distributions defining space use are normally estimated for time-scales ranging from weeks to months, obscuring much of the fine-scale information available from high-volume GPS data sets. By accounting for movement heterogeneity, the dBBMM provides a rigorous, behaviourally based estimate of space use between each set of relocations. Focusing on UDs generated between individual sets of locations allows us to quantify fine-scale circadian variation in habitat use. We used the dBBMM to estimate UDs bounding individual time steps for three terrestrial species with different life histories to illustrate how the method can be used to identify fine-scale variations in habitat use. We also demonstrate how dBBMMs can be used to characterize circadian patterns of habitat selection and link fine-scale patterns of habitat use to behaviour. We observed circadian patterns of habitat use that varied seasonally for a white-tailed deer (Odocoileus virginianus) and coyote (Canis latrans). We found seasonal patterns in selection by the white-tailed deer and were able to link use of conifer forests and agricultural fields to behavioural state of the coyote. Additionally, we were able to quantify the date in which a Rio Grande wild turkey (Meleagris gallopavo intermedia) initiated laying as well as when during the day, she was most likely to visit the nest site to deposit eggs. The ability to quantify circadian patterns of habitat use may have important implications for research and management of wildlife

  17. Pharmacokinetic modeling in aquatic animals. 1. Models and concepts

    USGS Publications Warehouse

    Barron, M.G.; Stehly, Guy R.; Hayton, W.L.

    1990-01-01

    While clinical and toxicological applications of pharmacokinetics have continued to evolve both conceptually and experimentally, pharmacokinetics modeling in aquatic animals has not progressed accordingly. In this paper we present methods and concepts of pharmacokinetic modeling in aquatic animals using multicompartmental, clearance-based, non-compartmental and physiologically-based pharmacokinetic models. These models should be considered as alternatives to traditional approaches, which assume that the animal acts as a single homogeneous compartment based on apparent monoexponential elimination.

  18. Animal Models for Periodontal Disease

    PubMed Central

    Oz, Helieh S.; Puleo, David A.

    2011-01-01

    Animal models and cell cultures have contributed new knowledge in biological sciences, including periodontology. Although cultured cells can be used to study physiological processes that occur during the pathogenesis of periodontitis, the complex host response fundamentally responsible for this disease cannot be reproduced in vitro. Among the animal kingdom, rodents, rabbits, pigs, dogs, and nonhuman primates have been used to model human periodontitis, each with advantages and disadvantages. Periodontitis commonly has been induced by placing a bacterial plaque retentive ligature in the gingival sulcus around the molar teeth. In addition, alveolar bone loss has been induced by inoculation or injection of human oral bacteria (e.g., Porphyromonas gingivalis) in different animal models. While animal models have provided a wide range of important data, it is sometimes difficult to determine whether the findings are applicable to humans. In addition, variability in host responses to bacterial infection among individuals contributes significantly to the expression of periodontal diseases. A practical and highly reproducible model that truly mimics the natural pathogenesis of human periodontal disease has yet to be developed. PMID:21331345

  19. Evaluation of animal models of neurobehavioral disorders

    PubMed Central

    van der Staay, F Josef; Arndt, Saskia S; Nordquist, Rebecca E

    2009-01-01

    Animal models play a central role in all areas of biomedical research. The process of animal model building, development and evaluation has rarely been addressed systematically, despite the long history of using animal models in the investigation of neuropsychiatric disorders and behavioral dysfunctions. An iterative, multi-stage trajectory for developing animal models and assessing their quality is proposed. The process starts with defining the purpose(s) of the model, preferentially based on hypotheses about brain-behavior relationships. Then, the model is developed and tested. The evaluation of the model takes scientific and ethical criteria into consideration. Model development requires a multidisciplinary approach. Preclinical and clinical experts should establish a set of scientific criteria, which a model must meet. The scientific evaluation consists of assessing the replicability/reliability, predictive, construct and external validity/generalizability, and relevance of the model. We emphasize the role of (systematic and extended) replications in the course of the validation process. One may apply a multiple-tiered 'replication battery' to estimate the reliability/replicability, validity, and generalizability of result. Compromised welfare is inherent in many deficiency models in animals. Unfortunately, 'animal welfare' is a vaguely defined concept, making it difficult to establish exact evaluation criteria. Weighing the animal's welfare and considerations as to whether action is indicated to reduce the discomfort must accompany the scientific evaluation at any stage of the model building and evaluation process. Animal model building should be discontinued if the model does not meet the preset scientific criteria, or when animal welfare is severely compromised. The application of the evaluation procedure is exemplified using the rat with neonatal hippocampal lesion as a proposed model of schizophrenia. In a manner congruent to that for improving animal

  20. 9 CFR 93.410 - Movement from conveyances to quarantine station.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Movement from conveyances to... PRODUCTS; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.410 Movement from... transportation of animals or their fresh products. When movement of the aforesaid ruminants upon or across a...

  1. Animal models.

    PubMed

    Walker, Ellen A

    2010-01-01

    As clinical studies reveal that chemotherapeutic agents may impair several different cognitive domains in humans, the development of preclinical animal models is critical to assess the degree of chemotherapy-induced learning and memory deficits and to understand the underlying neural mechanisms. In this chapter, the effects of various cancer chemotherapeutic agents in rodents on sensory processing, conditioned taste aversion, conditioned emotional response, passive avoidance, spatial learning, cued memory, discrimination learning, delayed-matching-to-sample, novel-object recognition, electrophysiological recordings and autoshaping is reviewed. It appears at first glance that the effects of the cancer chemotherapy agents in these many different models are inconsistent. However, a literature is emerging that reveals subtle or unique changes in sensory processing, acquisition, consolidation and retrieval that are dose- and time-dependent. As more studies examine cancer chemotherapeutic agents alone and in combination during repeated treatment regimens, the animal models will become more predictive tools for the assessment of these impairments and the underlying neural mechanisms. The eventual goal is to collect enough data to enable physicians to make informed choices about therapeutic regimens for their patients and discover new avenues of alternative or complementary therapies that reduce or eliminate chemotherapy-induced cognitive deficits.

  2. A unifying framework for quantifying the nature of animal interactions.

    PubMed

    Potts, Jonathan R; Mokross, Karl; Lewis, Mark A

    2014-07-06

    Collective phenomena, whereby agent-agent interactions determine spatial patterns, are ubiquitous in the animal kingdom. On the other hand, movement and space use are also greatly influenced by the interactions between animals and their environment. Despite both types of interaction fundamentally influencing animal behaviour, there has hitherto been no unifying framework for the models proposed in both areas. Here, we construct a general method for inferring population-level spatial patterns from underlying individual movement and interaction processes, a key ingredient in building a statistical mechanics for ecological systems. We show that resource selection functions, as well as several examples of collective motion models, arise as special cases of our framework, thus bringing together resource selection analysis and collective animal behaviour into a single theory. In particular, we focus on combining the various mechanistic models of territorial interactions in the literature with step selection functions, by incorporating interactions into the step selection framework and demonstrating how to derive territorial patterns from the resulting models. We demonstrate the efficacy of our model by application to a population of insectivore birds in the Amazon rainforest. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  3. Animal models of middle ear cholesteatoma.

    PubMed

    Yamamoto-Fukuda, Tomomi; Takahashi, Haruo; Koji, Takehiko

    2011-01-01

    Middle ear acquired cholesteatoma is a pathological condition associated with otitis media, which may be associated with temporal bone resorption, otorrhea and hearing loss, and occasionally various other complications. Cholesteatoma is characterized by the enhanced proliferation of epithelial cells with aberrant morphologic characteristics. Unfortunately, our understanding of the mechanism underlying its pathogenesis is limited. To investigate its pathogenesis, different animal models have been used. This paper provides a brief overview of the current status of research in the field of pathogenesis of middle ear acquired cholesteatoma, four types of animal models previously reported on, up-to-date cholesteatoma research using these animal models, our current studies of the local hybrid ear model, and the future prospect of new animal models of middle ear cholesteatoma.

  4. Animal Models of Middle Ear Cholesteatoma

    PubMed Central

    Yamamoto-Fukuda, Tomomi; Takahashi, Haruo; Koji, Takehiko

    2011-01-01

    Middle ear acquired cholesteatoma is a pathological condition associated with otitis media, which may be associated with temporal bone resorption, otorrhea and hearing loss, and occasionally various other complications. Cholesteatoma is characterized by the enhanced proliferation of epithelial cells with aberrant morphologic characteristics. Unfortunately, our understanding of the mechanism underlying its pathogenesis is limited. To investigate its pathogenesis, different animal models have been used. This paper provides a brief overview of the current status of research in the field of pathogenesis of middle ear acquired cholesteatoma, four types of animal models previously reported on, up-to-date cholesteatoma research using these animal models, our current studies of the local hybrid ear model, and the future prospect of new animal models of middle ear cholesteatoma. PMID:21541229

  5. An animal model for tinnitus.

    PubMed

    Jastreboff, P J; Brennan, J F; Sasaki, C T

    1988-03-01

    Subjective tinnitus remains obscure, widespread, and without apparent cure. In the absence of a suitable animal model, past investigations took place in humans, resulting in studies that were understandably restricted by the nature of human investigation. Within this context, the development of a valid animal model would be considered a major breakthrough in this field of investigation. Our results showed changes in the spontaneous activity of single neurons in the inferior colliculus, consistent with abnormally increased neuronal activity within the auditory pathways after manipulations known to produce tinnitus in man. A procedure based on a Pavlovian conditioned suppression paradigm was recently developed that allows us to measure tinnitus behaviorally in conscious animals. Accordingly, an animal model of tinnitus is proposed that permits tests of hypotheses relating to tinnitus generation, allowing the accommodation of interventional strategies for the treatment of this widespread auditory disorder.

  6. What's Wrong with "Animal Rights"?

    ERIC Educational Resources Information Center

    Morrison, Adrian R.

    1992-01-01

    School leaders must withstand the pressures of the animal rights movement to disrupt the science curriculum. It would be tragic if this movement succeeded in turning a large number of students against the legitimate use of animals and, ultimately, against biomedical research. (MLF)

  7. Seasonal climate variation and caribou availability: Modeling sequential movement using satellite-relocation data

    USGS Publications Warehouse

    Nicolson, Craig; Berman, Matthew; West, Colin Thor; Kofinas, Gary P.; Griffith, Brad; Russell, Don; Dugan, Darcy

    2013-01-01

    Livelihood systems that depend on mobile resources must constantly adapt to change. For people living in permanent settlements, environmental changes that affect the distribution of a migratory species may reduce the availability of a primary food source, with the potential to destabilize the regional social-ecological system. Food security for Arctic indigenous peoples harvesting barren ground caribou (Rangifer tarandus granti) depends on movement patterns of migratory herds. Quantitative assessments of physical, ecological, and social effects on caribou distribution have proven difficult because of the significant interannual variability in seasonal caribou movement patterns. We developed and evaluated a modeling approach for simulating the distribution of a migratory herd throughout its annual cycle over a multiyear period. Beginning with spatial and temporal scales developed in previous studies of the Porcupine Caribou Herd of Canada and Alaska, we used satellite collar locations to compute and analyze season-by-season probabilities of movement of animals between habitat zones under two alternative weather conditions for each season. We then built a set of transition matrices from these movement probabilities, and simulated the sequence of movements across the landscape as a Markov process driven by externally imposed seasonal weather states. Statistical tests showed that the predicted distributions of caribou were consistent with observed distributions, and significantly correlated with subsistence harvest levels for three user communities. Our approach could be applied to other caribou herds and could be adapted for simulating the distribution of other ungulates and species with similarly large interannual variability in the use of their range.

  8. Animal models of fibromyalgia

    PubMed Central

    2013-01-01

    Animal models of disease states are valuable tools for developing new treatments and investigating underlying mechanisms. They should mimic the symptoms and pathology of the disease and importantly be predictive of effective treatments. Fibromyalgia is characterized by chronic widespread pain with associated co-morbid symptoms that include fatigue, depression, anxiety and sleep dysfunction. In this review, we present different animal models that mimic the signs and symptoms of fibromyalgia. These models are induced by a wide variety of methods that include repeated muscle insults, depletion of biogenic amines, and stress. All potential models produce widespread and long-lasting hyperalgesia without overt peripheral tissue damage and thus mimic the clinical presentation of fibromyalgia. We describe the methods for induction of the model, pathophysiological mechanisms for each model, and treatment profiles. PMID:24314231

  9. Trackable life: Data, sequence, and organism in movement ecology.

    PubMed

    Benson, Etienne S

    2016-06-01

    Over the past decade an increasing number of ecologists have begun to frame their work as a contribution to the emerging research field of movement ecology. This field's primary object of research is the movement track, which is usually operationalized as a series of discrete "steps and stops" that represent a portion of an animal's "lifetime track." Its practitioners understand their field as dependent on recent technical advances in tracking organisms and analyzing their movements. By making movement their primary object of research, rather than simply an expression of deeper biological phenomena, movement ecologists are able to generalize across the movement patterns of a wide variety of species and to draw on statistical techniques developed to model the movements of non-living things. Although it can trace its roots back to a long tradition of statistical models of movement, the field relies heavily on metaphors from genomics; in particular, movement tracks have been seen as similar to DNA sequences. Though this has helped movement ecology consolidate around a shared understanding of movement, the field may need to broaden its understanding of movement beyond the sequence if it is to realize its potential to address urgent concerns such as biodiversity loss. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Effects of Land Cover on the Movement of Frugivorous Birds in a Heterogeneous Landscape.

    PubMed

    Da Silveira, Natalia Stefanini; Niebuhr, Bernardo Brandão S; Muylaert, Renata de Lara; Ribeiro, Milton Cezar; Pizo, Marco Aurélio

    2016-01-01

    Movement is a key spatiotemporal process that enables interactions between animals and other elements of nature. The understanding of animal trajectories and the mechanisms that influence them at the landscape level can yield insight into ecological processes and potential solutions to specific ecological problems. Based upon optimal foraging models and empirical evidence, we hypothesized that movement by thrushes is highly tortuous (low average movement speeds and homogeneous distribution of turning angles) inside forests, moderately tortuous in urban areas, which present intermediary levels of resources, and minimally tortuous (high movement speeds and turning angles next to 0 radians) in open matrix types (e.g., crops and pasture). We used data on the trajectories of two common thrush species (Turdus rufiventris and Turdus leucomelas) collected by radio telemetry in a fragmented region in Brazil. Using a maximum likelihood model selection approach we fit four probability distribution models to average speed data, considering short-tailed, long-tailed, and scale-free distributions (to represent different regimes of movement variation), and one distribution to relative angle data. Models included land cover type and distance from forest-matrix edges as explanatory variables. Speed was greater farther away from forest edges and increased faster inside forest habitat compared to urban and open matrices. However, turning angle was not influenced by land cover. Thrushes presented a very tortuous trajectory, with many displacements followed by turns near 180 degrees. Thrush trajectories resembled habitat and edge dependent, tortuous random walks, with a well-defined movement scale inside each land cover type. Although thrushes are habitat generalists, they showed a greater preference for forest edges, and thus may be considered edge specialists. Our results reinforce the importance of studying animal movement patterns in order to understand ecological processes such as

  11. Rapid eye movements during sleep in mice: High trait-like stability qualifies rapid eye movement density for characterization of phenotypic variation in sleep patterns of rodents

    PubMed Central

    2011-01-01

    Background In humans, rapid eye movements (REM) density during REM sleep plays a prominent role in psychiatric diseases. Especially in depression, an increased REM density is a vulnerability marker for depression. In clinical practice and research measurement of REM density is highly standardized. In basic animal research, almost no tools are available to obtain and systematically evaluate eye movement data, although, this would create increased comparability between human and animal sleep studies. Methods We obtained standardized electroencephalographic (EEG), electromyographic (EMG) and electrooculographic (EOG) signals from freely behaving mice. EOG electrodes were bilaterally and chronically implanted with placement of the electrodes directly between the musculus rectus superior and musculus rectus lateralis. After recovery, EEG, EMG and EOG signals were obtained for four days. Subsequent to the implantation process, we developed and validated an Eye Movement scoring in Mice Algorithm (EMMA) to detect REM as singularities of the EOG signal, based on wavelet methodology. Results The distribution of wakefulness, non-REM (NREM) sleep and rapid eye movement (REM) sleep was typical of nocturnal rodents with small amounts of wakefulness and large amounts of NREM sleep during the light period and reversed proportions during the dark period. REM sleep was distributed correspondingly. REM density was significantly higher during REM sleep than NREM sleep. REM bursts were detected more often at the end of the dark period than the beginning of the light period. During REM sleep REM density showed an ultradian course, and during NREM sleep REM density peaked at the beginning of the dark period. Concerning individual eye movements, REM duration was longer and amplitude was lower during REM sleep than NREM sleep. The majority of single REM and REM bursts were associated with micro-arousals during NREM sleep, but not during REM sleep. Conclusions Sleep-stage specific

  12. Animal models of sepsis.

    PubMed

    Fink, Mitchell P

    2014-01-01

    Sepsis remains a common, serious, and heterogeneous clinical entity that is difficult to define adequately. Despite its importance as a public health problem, efforts to develop and gain regulatory approval for a specific therapeutic agent for the adjuvant treatment of sepsis have been remarkably unsuccessful. One step in the critical pathway for the development of a new agent for adjuvant treatment of sepsis is evaluation in an appropriate animal model of the human condition. Unfortunately, the animal models that have been used for this purpose have often yielded misleading findings. It is likely that there are multiple reasons for the discrepancies between the results obtained in tests of pharmacological agents in animal models of sepsis and the outcomes of human clinical trials. One of important reason may be that the changes in gene expression, which are triggered by trauma or infection, are different in mice, a commonly used species for preclinical testing, and humans. Additionally, many species, including mice and baboons, are remarkably resistant to the toxic effects of bacterial lipopolysaccharide, whereas humans are exquisitely sensitive. New approaches toward the use of animals for sepsis research are being investigated. But, at present, results from preclinical studies of new therapeutic agents for sepsis must be viewed with a degree of skepticism.

  13. Spatial ecology and movement of reintroduced Canada lynx

    USGS Publications Warehouse

    Buderman, Frances E.; Hooten, Mevin B.; Ivan, Jacob S.; Shenk, Tanya

    2017-01-01

    Understanding movement behavior and identifying areas of landscape connectivity is critical for the conservation of many species. However, collecting fine‐scale movement data can be prohibitively time consuming and costly, especially for rare or endangered species, whereas existing data sets may provide the best available information on animal movement. Contemporary movement models may not be an option for modeling existing data due to low temporal resolution and large or unusual error structures, but inference can still be obtained using a functional movement modeling approach. We use a functional movement model to perform a population‐level analysis of telemetry data collected during the reintroduction of Canada lynx to Colorado. Little is known about southern lynx populations compared to those in Canada and Alaska, and inference is often limited to a few individuals due to their low densities. Our analysis of a population of Canada lynx fills significant gaps in the knowledge of Canada lynx behavior at the southern edge of its historical range. We analyzed functions of individual‐level movement paths, such as speed, residence time, and tortuosity, and identified a region of connectivity that extended north from the San Juan Mountains, along the continental divide, and terminated in Wyoming at the northern edge of the Southern Rocky Mountains. Individuals were able to traverse large distances across non‐boreal habitat, including exploratory movements to the Greater Yellowstone area and beyond. We found evidence for an effect of seasonality and breeding status on many of the movement quantities and documented a potential reintroduction effect. Our findings provide the first analysis of Canada lynx movement in Colorado and substantially augment the information available for conservation and management decisions. The functional movement framework can be extended to other species and demonstrates that information on movement behavior can be obtained using

  14. A holistic measurement model of movement competency in children.

    PubMed

    Rudd, J; Butson, M L; Barnett, L; Farrow, D; Berry, J; Borkoles, E; Polman, R

    2016-01-01

    Different countries have different methods for assessing movement competence in children; however, it is unclear whether the test batteries that are used measure the same aspects of movement competence. The aim of this paper was to (1) investigate whether the Test of Gross Motor Development (TGMD-2) and Körperkoordinations Test für Kinder (KTK) measure the same aspects of children's movement competence and (2) examine the factorial structure of the TGMD-2 and KTK in a sample of Australian children. A total of 158 children participated (M age = 9.5; SD = 2.2). First, confirmatory factor analysis examined the independent factorial structure of the KTK and TGMD-2. Second, it was investigated whether locomotor, object control and body coordination loaded on the latent variable Movement Competency. Confirmatory factor analysis indicated an adequate fit for both the KTK and TGMD-2. An adequate fit was also achieved for the final model. In this model, locomotor (r = .86), object control (r = .71) and body coordination (r = .52) loaded on movement competence. Findings support our hypothesis that the TGMD-2 and KTK measure discrete aspects of movement competence. Future researchers and practitioners should consider using a wider range of test batteries to assess movement competence.

  15. Analysis of Transforming Growth Factor- β1 Expression in Resorptive Lacunae following Orthodontic Tooth Movement in An Animal Model.

    PubMed

    Seifi, Massoud; Kazemi, Bahram; Kabiri, Sattar; Badiee, Mohammadreza

    2017-01-01

    Root resorption is a complication of orthodontic treatment and till date, there is a dearth of information regarding this issue. The aim of this study was to determine whether the expression of transforming growth factor-β1 (TGF-β1, an inflammatory cytokine) is related to orthodontic force. Moreover, if associated, the expression level may be helpful in differential diagnosis, control and ultimate treatment of the disease. In this experimental study, a total of 24 eight-week-old male Wistar rats were selected randomly. On day 0, an orthodontic appliance, which consisted of a closed coil spring, was ligated to the upper right first molar and incisor. The upper left first molar in these animals was not placed under orthodontic force, thus serving as the control group. On day 21, after anesthesia, the animals were sacrificed. The rats were then divided into two equal groups where the first group was subjected to histological evaluation and the second group to reverse transcriptase-polymerase chain reaction (RT-PCR). Orthodontic tooth movement was measured in both groups to determine the influence of the applied force. Statistical analysis of data showed a significant root resorption between the experimental group and control group (P<0.05), however, there was no significant difference in the expression level of the inflammatory cytokine, TGF-β1 . Based on the findings of this study, we suggest that there is a direct relationship between orthodontic force and orthodontic induced inflammatory root resorption. In addition, no relationship is likely to exist between root resorption and TGF-β1 expression in the resorptive lacunae.

  16. Animal models for rotator cuff repair.

    PubMed

    Lebaschi, Amir; Deng, Xiang-Hua; Zong, Jianchun; Cong, Guang-Ting; Carballo, Camila B; Album, Zoe M; Camp, Christopher; Rodeo, Scott A

    2016-11-01

    Rotator cuff (RC) injuries represent a significant source of pain, functional impairment, and morbidity. The large disease burden of RC pathologies necessitates rapid development of research methodologies to treat these conditions. Given their ability to model anatomic, biomechanical, cellular, and molecular aspects of the human RC, animal models have played an indispensable role in reducing injury burden and advancing this field of research for many years. The development of animal models in the musculoskeletal (MSK) research arena is uniquely different from that in other fields in that the similarity of macrostructures and functions is as critical to replicate as cellular and molecular functions. Traditionally, larger animals have been used because of their anatomic similarity to humans and the ease of carrying out realistic surgical procedures. However, refinement of current molecular methods, introduction of novel research tools, and advancements in microsurgical techniques have increased the applicability of small animal models in MSK research. In this paper, we review RC animal models and emphasize a murine model that may serve as a valuable instrument for future RC tendon repair investigations. © 2016 New York Academy of Sciences.

  17. Social network models predict movement and connectivity in ecological landscapes

    USGS Publications Warehouse

    Fletcher, R.J.; Acevedo, M.A.; Reichert, Brian E.; Pias, Kyle E.; Kitchens, W.M.

    2011-01-01

    Network analysis is on the rise across scientific disciplines because of its ability to reveal complex, and often emergent, patterns and dynamics. Nonetheless, a growing concern in network analysis is the use of limited data for constructing networks. This concern is strikingly relevant to ecology and conservation biology, where network analysis is used to infer connectivity across landscapes. In this context, movement among patches is the crucial parameter for interpreting connectivity but because of the difficulty of collecting reliable movement data, most network analysis proceeds with only indirect information on movement across landscapes rather than using observed movement to construct networks. Statistical models developed for social networks provide promising alternatives for landscape network construction because they can leverage limited movement information to predict linkages. Using two mark-recapture datasets on individual movement and connectivity across landscapes, we test whether commonly used network constructions for interpreting connectivity can predict actual linkages and network structure, and we contrast these approaches to social network models. We find that currently applied network constructions for assessing connectivity consistently, and substantially, overpredict actual connectivity, resulting in considerable overestimation of metapopulation lifetime. Furthermore, social network models provide accurate predictions of network structure, and can do so with remarkably limited data on movement. Social network models offer a flexible and powerful way for not only understanding the factors influencing connectivity but also for providing more reliable estimates of connectivity and metapopulation persistence in the face of limited data.

  18. Is that really my movement? - Students' experiences of a video-supported interactive learning model for movement awareness.

    PubMed

    Backåberg, Sofia; Gummesson, Christina; Brunt, David; Rask, Mikael

    2015-01-01

    Healthcare staff and students have a great risk of developing musculoskeletal symptoms. One cause of this is heavy load related work activities such as manual handling, in which the quality of individual work technique may play a major role. Preventive interventions and well-defined educational strategies to support movement awareness and long-lasting movement changes need to be developed. The aim of the present study was to explore nursing students' experiences of a newly developed interactive learning model for movement awareness. The learning model, which is based on a life-world perspective with focus on interpersonal interaction, has been used with 11 undergraduate students from the second and final year. Each student participated in three individual video sessions with a facilitator. Two individual interviews were carried out with each student during the learning process and one interview 12-18 months after the last session. The interviews were audio-recorded and transcribed verbatim, and a phenomenological hermeneutic method inspired by Paul Ricoeur and described by Lindseth and Norberg was used to interpret the interviews and diary notes. The interpretation resulted in three key themes and nine subthemes. The key themes were; "Obtaining better preconditions for bodily awareness," "Experiencing changes in one's own movement," and "Experiencing challenges in the learning process." The interactive learning model entails a powerful and challenging experience that develops movement awareness. The experience of meaningfulness and usefulness emerges increasingly and alternates with a feeling of discomfort. The learning model may contribute to the body of knowledge of well-defined educational strategies in movement awareness and learning in, for example, preventive interventions and ergonomic education. It may also be valuable in other practical learning situations where movement awareness is required.

  19. 9 CFR 82.24 - Other interstate movements and special permits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Other interstate movements and special... NEWCASTLE DIS- EASE (END) AND CHLAMYDIOSIS Chlamydiosis in Poultry § 82.24 Other interstate movements and special permits. (a) A special permit is required for the interstate movement of items whose movement...

  20. Modeling individual movement decisions of brown hare (Lepus europaeus) as a key concept for realistic spatial behavior and exposure: A population model for landscape-level risk assessment.

    PubMed

    Kleinmann, Joachim U; Wang, Magnus

    2017-09-01

    Spatial behavior is of crucial importance for the risk assessment of pesticides and for the assessment of effects of agricultural practice or multiple stressors, because it determines field use, exposition, and recovery. Recently, population models have increasingly been used to understand the mechanisms driving risk and recovery or to conduct landscape-level risk assessments. To include spatial behavior appropriately in population models for use in risk assessments, a new method, "probabilistic walk," was developed, which simulates the detailed daily movement of individuals by taking into account food resources, vegetation cover, and the presence of conspecifics. At each movement step, animals decide where to move next based on probabilities being determined from this information. The model was parameterized to simulate populations of brown hares (Lepus europaeus). A detailed validation of the model demonstrated that it can realistically reproduce various natural patterns of brown hare ecology and behavior. Simulated proportions of time animals spent in fields (PT values) were also comparable to field observations. It is shown that these important parameters for the risk assessment may, however, vary in different landscapes. The results demonstrate the value of using population models to reduce uncertainties in risk assessment and to better understand which factors determine risk in a landscape context. Environ Toxicol Chem 2017;36:2299-2307. © 2017 SETAC. © 2017 SETAC.

  1. Animal models for filovirus infections.

    PubMed

    Siragam, Vinayakumar; Wong, Gary; Qiu, Xiang-Guo

    2018-01-18

    The family Filoviridae , which includes the genera Marburgvirus and Ebolavirus , contains some of the most pathogenic viruses in humans and non-human primates (NHPs), causing severe hemorrhagic fevers with high fatality rates. Small animal models against filoviruses using mice, guinea pigs, hamsters, and ferrets have been developed with the goal of screening candidate vaccines and antivirals, before testing in the gold standard NHP models. In this review, we summarize the different animal models used to understand filovirus pathogenesis, and discuss the advantages and disadvantages of each model with respect to filovirus disease research.

  2. Animal models for filovirus infections

    PubMed Central

    Siragam, Vinayakumar; Wong, Gary; Qiu, Xiang-Guo

    2018-01-01

    The family Filoviridae, which includes the genera Marburgvirus and Ebolavirus, contains some of the most pathogenic viruses in humans and non-human primates (NHPs), causing severe hemorrhagic fevers with high fatality rates. Small animal models against filoviruses using mice, guinea pigs, hamsters, and ferrets have been developed with the goal of screening candidate vaccines and antivirals, before testing in the gold standard NHP models. In this review, we summarize the different animal models used to understand filovirus pathogenesis, and discuss the advantages and disadvantages of each model with respect to filovirus disease research. PMID:29511141

  3. Animal models for testing anti-prion drugs.

    PubMed

    Fernández-Borges, Natalia; Elezgarai, Saioa R; Eraña, Hasier; Castilla, Joaquín

    2013-01-01

    Prion diseases belong to a group of fatal infectious diseases with no effective therapies available. Throughout the last 35 years, less than 50 different drugs have been tested in different experimental animal models without hopeful results. An important limitation when searching for new drugs is the existence of appropriate models of the disease. The three different possible origins of prion diseases require the existence of different animal models for testing anti-prion compounds. Wild type, over-expressing transgenic mice and other more sophisticated animal models have been used to evaluate a diversity of compounds which some of them were previously tested in different in vitro experimental models. The complexity of prion diseases will require more pre-screening studies, reliable sporadic (or spontaneous) animal models and accurate chemical modifications of the selected compounds before having an effective therapy against human prion diseases. This review is intended to put on display the more relevant animal models that have been used in the search of new antiprion therapies and describe some possible procedures when handling chemical compounds presumed to have anti-prion activity prior to testing them in animal models.

  4. A review on animal models and treatments for the reconstruction of Achilles and flexor tendons.

    PubMed

    Bottagisio, Marta; Lovati, Arianna B

    2017-03-01

    Tendon is a connective tissue mainly composed of collagen fibers with peculiar mechanical properties essential to functional movements. The increasing incidence of tendon traumatic injuries and ruptures-associated or not with the loss of tissue-falls on the growing interest in the field of tissue engineering and regenerative medicine. The use of animal models is mandatory to deepen the knowledge of the tendon healing response to severe damages or acute transections. Thus, the selection of preclinical models is crucial to ensure a successful translation of effective and safe innovative treatments to the clinical practice. The current review is focused on animal models of tendon ruptures and lacerations or defective injuries with large tissue loss that require surgical approaches or grafting procedures. Data published between 2000 and 2016 were examined. The analyzed articles were compiled from Pub Med-NCBI using search terms, including animal model(s) AND tendon augmentation OR tendon substitute(s) OR tendon substitution OR tendon replacement OR tendon graft(s) OR tendon defect(s) OR tendon rupture(s). This article presents the existing preclinical models - considering their advantages and disadvantages-in which translational progresses have been made by using bioactive sutures or tissue engineering that combines biomaterials with cells and growth factors to efficiently treat transections or large defects of Achilles and flexor tendons.

  5. Animal Models of Bone Metastasis

    PubMed Central

    Simmons, J. K.; Hildreth, B. E.; Supsavhad, W.; Elshafae, S. M.; Hassan, B. B.; Dirksen, W. P.; Toribio, R. E.; Rosol, T. J.

    2015-01-01

    Bone is one of the most common sites of cancer metastasis in humans and is a significant source of morbidity and mortality. Bone metastases are considered incurable and result in pain, pathologic fracture, and decreased quality of life. Animal models of skeletal metastases are essential to improve the understanding of the molecular pathways of cancer metastasis and growth in bone and to develop new therapies to inhibit and prevent bone metastases. The ideal animal model should be clinically relevant, reproducible, and representative of human disease. Currently, an ideal model does not exist; however, understanding the strengths and weaknesses of the available models will lead to proper study design and successful cancer research. This review provides an overview of the current in vivo animal models used in the study of skeletal metastases or local tumor invasion into bone and focuses on mammary and prostate cancer, lymphoma, multiple myeloma, head and neck squamous cell carcinoma, and miscellaneous tumors that metastasize to bone. PMID:26021553

  6. Simplification of the kinematic model of human movement

    NASA Astrophysics Data System (ADS)

    Dusza, Jacek J.; Wawrzyniak, Zbigniew M.; del Prado Martinez, David

    2013-10-01

    The paper presents a methods of simplification of the human gait model. The experimental data were obtained in the laboratory of the group SATI in the Electronics Engineering Department of the University of Valencia. As a result of the Mean Double Step (MDS) procedure, the human motion were described by a matrix containing the Cartesian coordinates of 26 markers placed on the human body recorded in the 100 time points. With these data it has been possible to develop an software application which performs a wide diversity of tasks like array simplification, mask calculation for the simplification, error calculation as well as tools for signals comparison and movement animation of the markers. Simplifications were made by the spectral analysis of signals and calculating the standard deviation of the differences between the signal and its approximation. Using this method the signals of displacement could be written as the time series limited to a small number of harmonic signals. This approach allows us for a high degree of data compression. The model presented in this work can be applied into the context of medical diagnostics or rehabilitation because for a given approximation error and a large number of harmonics may demonstrate some abnormalities (of orthopaedic symptoms) in the gait cycle analysis.

  7. Animal Models of Hemophilia

    PubMed Central

    Sabatino, Denise E.; Nichols, Timothy C.; Merricks, Elizabeth; Bellinger, Dwight A.; Herzog, Roland W.; Monahan, Paul E.

    2013-01-01

    The X-linked bleeding disorder hemophilia is caused by mutations in coagulation factor VIII (hemophilia A) or factor IX (hemophilia B). Unless prophylactic treatment is provided, patients with severe disease (less than 1% clotting activity) typically experience frequent spontaneous bleeds. Current treatment is largely based on intravenous infusion of recombinant or plasma-derived coagulation factor concentrate. More effective factor products are being developed. Moreover, gene therapies for sustained correction of hemophilia are showing much promise in pre-clinical studies and in clinical trials. These advances in molecular medicine heavily depend on availability of well-characterized small and large animal models of hemophilia, primarily hemophilia mice and dogs. Experiments in these animals represent important early and intermediate steps of translational research aimed at development of better and safer treatments for hemophilia, such a protein and gene therapies or immune tolerance protocols. While murine models are excellent for studies of large groups of animals using genetically defined strains, canine models are important for testing scale-up and for longer-term follow-up as well as for studies that require larger blood volumes. PMID:22137432

  8. Animal models of exercise and obesity.

    PubMed

    Kasper, Christine E

    2013-01-01

    Animal models have been invaluable in the conduct of nursing research for the past 40 years. This review will focus on specific animal models that can be used in nursing research to study the physiologic phenomena of exercise and obesity when the use of human subjects is either scientifically premature or inappropriate because of the need for sampling tissue or the conduct of longitudinal studies of aging. There exists an extensive body of literature reporting the experimental use of various animal models, in both exercise science and the study of the mechanisms of obesity. Many of these studies are focused on the molecular and genetic mechanisms of organ system adaptation and plasticity in response to exercise, obesity, or both. However, this review will narrowly focus on the models useful to nursing research in the study of exercise in the clinical context of increasing performance and mobility, atrophy and bedrest, fatigue, and aging. Animal models of obesity focus on those that best approximate clinical pathology.

  9. Using Computational and Mechanical Models to Study Animal Locomotion

    PubMed Central

    Miller, Laura A.; Goldman, Daniel I.; Hedrick, Tyson L.; Tytell, Eric D.; Wang, Z. Jane; Yen, Jeannette; Alben, Silas

    2012-01-01

    Recent advances in computational methods have made realistic large-scale simulations of animal locomotion possible. This has resulted in numerous mathematical and computational studies of animal movement through fluids and over substrates with the purpose of better understanding organisms’ performance and improving the design of vehicles moving through air and water and on land. This work has also motivated the development of improved numerical methods and modeling techniques for animal locomotion that is characterized by the interactions of fluids, substrates, and structures. Despite the large body of recent work in this area, the application of mathematical and numerical methods to improve our understanding of organisms in the context of their environment and physiology has remained relatively unexplored. Nature has evolved a wide variety of fascinating mechanisms of locomotion that exploit the properties of complex materials and fluids, but only recently are the mathematical, computational, and robotic tools available to rigorously compare the relative advantages and disadvantages of different methods of locomotion in variable environments. Similarly, advances in computational physiology have only recently allowed investigators to explore how changes at the molecular, cellular, and tissue levels might lead to changes in performance at the organismal level. In this article, we highlight recent examples of how computational, mathematical, and experimental tools can be combined to ultimately answer the questions posed in one of the grand challenges in organismal biology: “Integrating living and physical systems.” PMID:22988026

  10. Animal models: an important tool in mycology.

    PubMed

    Capilla, Javier; Clemons, Karl V; Stevens, David A

    2007-12-01

    Animal models of fungal infections are, and will remain, a key tool in the advancement of the medical mycology. Many different types of animal models of fungal infection have been developed, with murine models the most frequently used, for studies of pathogenesis, virulence, immunology, diagnosis, and therapy. The ability to control numerous variables in performing the model allows us to mimic human disease states and quantitatively monitor the course of the disease. However, no single model can answer all questions and different animal species or different routes of infection can show somewhat different results. Thus, the choice of which animal model to use must be made carefully, addressing issues of the type of human disease to mimic, the parameters to follow and collection of the appropriate data to answer those questions being asked. This review addresses a variety of uses for animal models in medical mycology. It focuses on the most clinically important diseases affecting humans and cites various examples of the different types of studies that have been performed. Overall, animal models of fungal infection will continue to be valuable tools in addressing questions concerning fungal infections and contribute to our deeper understanding of how these infections occur, progress and can be controlled and eliminated.

  11. A model for nonexercising hindlimb muscles in exercising animals.

    PubMed

    Bonen, A; Blewett, C; McDermott, J C; Elder, G C

    1990-07-01

    Nonexercising muscles appear to be metabolically active during exercise. Animal models for this purpose have not been established. However, we have been able to teach animals to run on their forelimbs while their hindlimbs are suspended above the treadmill with no visible limb movement. To document that indeed this mode of exercise does not provoke additional muscle activity, we have compared the levels of neural activation of the soleus and plantaris muscles using a computer analysis of the electromyographic interference pattern, recorded from bipolar fine wire electrodes implanted across each muscle. Via computer analyses of the electromyographic interference patterns the frequencies and amplitudes of motor unit action potentials were obtained. The data were sampled during 20 s of every minute of observation. Comparisons were made in four conditions: (i) resting on the treadmill while bearing weight on the hindlimbs (normal rest), (ii) running on the treadmill (15 m/min, 8% grade) on all four limbs (normal exercise), (iii) resting while the hindlimbs were suspended in a harness above the treadmill (suspended rest), and (iv) exercising with the forelimbs (15 m/min, 8% grade) while the hindlimbs were suspended above the treadmill (suspended exercise). All four experimental conditions were carried out for 90 min each and were performed by each animal. The results clearly show that muscle activities (frequencies and amplitudes), when the hindlimbs are suspended above the treadmill, at rest or during exercise, are lower than the activities in these same muscles when the animals are at rest, supporting only their body weight. Activities in the same muscles during exercise were from 300 to 2000% greater than during hindlimb suspension.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. An ocular biomechanic model for dynamic simulation of different eye movements.

    PubMed

    Iskander, J; Hossny, M; Nahavandi, S; Del Porto, L

    2018-04-11

    Simulating and analysing eye movement is useful for assessing visual system contribution to discomfort with respect to body movements, especially in virtual environments where simulation sickness might occur. It can also be used in the design of eye prosthesis or humanoid robot eye. In this paper, we present two biomechanic ocular models that are easily integrated into the available musculoskeletal models. The model was previously used to simulate eye-head coordination. The models are used to simulate and analyse eye movements. The proposed models are based on physiological and kinematic properties of the human eye. They incorporate an eye-globe, orbital suspension tissues and six muscles with their connective tissues (pulleys). Pulleys were incorporated in rectus and inferior oblique muscles. The two proposed models are the passive pulleys and the active pulleys models. Dynamic simulations of different eye movements, including fixation, saccade and smooth pursuit, are performed to validate both models. The resultant force-length curves of the models were similar to the experimental data. The simulation results show that the proposed models are suitable to generate eye movement simulations with results comparable to other musculoskeletal models. The maximum kinematic root mean square error (RMSE) is 5.68° and 4.35° for the passive and active pulley models, respectively. The analysis of the muscle forces showed realistic muscle activation with increased muscle synergy in the active pulley model. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Moving in the Anthropocene: Global reductions in terrestrial mammalian movements

    USGS Publications Warehouse

    Tucker, Marlee A.; Böhning-Gaese, Katrin; Fagan, William F.; Fryxell, John; Van Moorter, Bram; Alberts, Susan C; Ali, Abdullahi H.; Allen, Andrew M.; Attias, Nina; Avgar, Tal; Bartlam-Brooks, Hattie; Bayarbaatar, Buuveibaatar; Belant, Jerrold L.; Bertassoni, Alessandra; Beyer, Dean; Bidner, Laura; M. van Beest, Floris; Blake, Stephen; Blaum, Niels; Bracis, Chloe; Brown, Danielle; Nico de Bruyn, P. J.; Cagnacci, Francesca; Calabrese, J.M.; Camilo-Alves, Constança; Chamaillé-Jammes, Simon; Chiaradia, Andre; Davidson, Sarah C.; Dennis, Todd; DeStefano, Stephen; Diefenbach, Duane R.; Douglas-Hamilton, Iain; Fennessy, Julian; Fichtel, Claudia; Fiedler, Wolfgang; Fischer, Christina; Fischhoff, Ilya; Fleming, Christen H.; Ford, Adam T.; Fritz, Susanne A.; Gehr, Benedikt; Goheen, Jacob R.; Gurarie, Eliezer; Hebblewhite, Mark; Heurich, Marco; Mark Hewison, A.J.; Hof, Christian; Hurme, Edward; Isbell, Lynne A.; Janssen, René; Jeltsch, Florian; Kaczensky, Petra; Kane, Adam; Kappeler, Peter M.; Kauffman, Matthew J.; Kays, Roland; Kimuyu, Duncan; Koch, Flavia; Kranstauber, Bart; LaPoint, Scott; Leimgruber, Peter; Linnell, John D. C.; López-López, Pascual; Markham, A. Catherine; Mattisson, Jenny; Medici, Emilia Patricia; Mellone, Ugo; Merrill, E.; de Miranda Mourão, Guilherme; Morato, Ronaldo G.; Morellet, Nicolas; Morrison, Thomas A.; Díaz-Muñoz, Samuel L.; Mysterud, Atle; Nandintsetseg, Dejid; Nathan, Ran; Niamir, Aidin; Odden, John; O'Hara, Robert B.; Oliveira-Santos, Luiz G. R.; Olson, Kirk A.; Patterson, Bruce D.; Cunha de Paula, Rogerio; Pedrotti, Luca; Reineking, Björn; Rimmler, Martin; Rogers, T.L.; Rolandsen, Christer Moe; Rosenberry, Christopher S.; Rubenstein, Daniel I.; Safi, Kamran; Saïd, Sonia; Sapir, Nir; Sawyer, Hall; Schmidt, Niels Martin; Selva, Nuria; Sergiel, Agnieszka; Shiilegdamba, Enkhtuvshin; Silva, João Paulo; Singh, N.; Solberg, Erling J.; Spiegel, Orr; Strand, Olav; Sundaresan, S.R.; Ullmann, Wiebke; Voigt, Ulrich; Wall, J.; Wattles, David W.; Wikelski, Martin; Wilmers, Christopher C.; Wilson, Jon W.; Wittemyer, George; Zięba, Filip; Zwijacz-Kozica, Tomasz; Mueller, Thomas

    2018-01-01

    Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission.

  14. An Explanatory Model of Teacher Movement within Ontario School Boards

    ERIC Educational Resources Information Center

    Sibbald, Timothy M.

    2017-01-01

    Teacher movement within school boards is examined using multiple case study. Emergent themes achieved theoretical saturation and are consistent with the research literature. In this paper, the relationships between the themes are used to develop a substantive theoretical model of teacher movement within school boards. The model uses a two-phase…

  15. Analysis of Transforming Growth Factor- β1 Expression in Resorptive Lacunae following Orthodontic Tooth Movement in An Animal Model

    PubMed Central

    Seifi, Massoud; Kazemi, Bahram; Kabiri, Sattar; Badiee, Mohammadreza

    2017-01-01

    Objective Root resorption is a complication of orthodontic treatment and till date, there is a dearth of information regarding this issue. The aim of this study was to determine whether the expression of transforming growth factor-β1 (TGF-β1, an inflammatory cytokine) is related to orthodontic force. Moreover, if associated, the expression level may be helpful in differential diagnosis, control and ultimate treatment of the disease. Materials and Methods In this experimental study, a total of 24 eight-week-old male Wistar rats were selected randomly. On day 0, an orthodontic appliance, which consisted of a closed coil spring, was ligated to the upper right first molar and incisor. The upper left first molar in these animals was not placed under orthodontic force, thus serving as the control group. On day 21, after anesthesia, the animals were sacrificed. The rats were then divided into two equal groups where the first group was subjected to histological evaluation and the second group to reverse transcriptase-polymerase chain reaction (RT-PCR). Orthodontic tooth movement was measured in both groups to determine the influence of the applied force. Results Statistical analysis of data showed a significant root resorption between the experimental group and control group (P<0.05), however, there was no significant difference in the expression level of the inflammatory cytokine, TGF-β1. Conclusion Based on the findings of this study, we suggest that there is a direct relationship between orthodontic force and orthodontic induced inflammatory root resorption. In addition, no relationship is likely to exist between root resorption and TGF-β1 expression in the resorptive lacunae. PMID:28670520

  16. Animal models of pituitary neoplasia

    PubMed Central

    Lines, K.E.; Stevenson, M.; Thakker, R.V.

    2016-01-01

    Pituitary neoplasias can occur as part of a complex inherited disorder, or more commonly as sporadic (non-familial) disease. Studies of the molecular and genetic mechanisms causing such pituitary tumours have identified dysregulation of >35 genes, with many revealed by studies in mice, rats and zebrafish. Strategies used to generate these animal models have included gene knockout, gene knockin and transgenic over-expression, as well as chemical mutagenesis and drug induction. These animal models provide an important resource for investigation of tissue-specific tumourigenic mechanisms, and evaluations of novel therapies, illustrated by studies into multiple endocrine neoplasia type 1 (MEN1), a hereditary syndrome in which ∼30% of patients develop pituitary adenomas. This review describes animal models of pituitary neoplasia that have been generated, together with some recent advances in gene editing technologies, and an illustration of the use of the Men1 mouse as a pre clinical model for evaluating novel therapies. PMID:26320859

  17. Food allergy animal models: an overview.

    PubMed

    Helm, Ricki M

    2002-05-01

    Specific food allergy is characterized by sensitization to innocuous food proteins with production of allergen-specific IgE that binds to receptors on basophils and mast cells. Upon recurrent exposure to the same allergen, an allergic response is induced by mediator release following cross-linking of cell-bound allergen-specific IgE. The determination of what makes an innocuous food protein an allergen in predisposed individuals is unknown; however, mechanistic and protein allergen predictive models are being actively investigated in a number of animal models. Currently, there is no animal model that will actively profile known food allergens, predict the allergic potential of novel food proteins, or demonstrate clinically the human food allergic sensitization/allergic response. Animal models under investigation include mice, rats, the guinea pig, atopic dog, and neonatal swine. These models are being assessed for production of IgE, clinical responses to re-exposure, and a ranking of food allergens (based on potency) including a nonfood allergen protein source. A selection of animal models actively being investigated that will contribute to our understanding of what makes a protein an allergen and future predictive models for assessing the allergenicity of novel proteins is presented in this review.

  18. Animal models of Parkinson's disease: limits and relevance to neuroprotection studies.

    PubMed

    Bezard, Erwan; Yue, Zhenyu; Kirik, Deniz; Spillantini, Maria Grazia

    2013-01-01

    Over the last two decades, significant strides has been made toward acquiring a better knowledge of both the etiology and pathogenesis of Parkinson's disease (PD). Experimental models are of paramount importance to obtain greater insights into the pathogenesis of the disease. Thus far, neurotoxin-based animal models have been the most popular tools employed to produce selective neuronal death in both in vitro and in vivo systems. These models have been commonly referred to as the pathogenic models. The current trend in modeling PD revolves around what can be called the disease gene-based models or etiologic models. The value of utilizing multiple models with a different mechanism of insult rests on the premise that dopamine-producing neurons die by stereotyped cascades that can be activated by a range of insults, from neurotoxins to downregulation and overexpression of disease-related genes. In this position article, we present the relevance of both pathogenic and etiologic models as well as the concept of clinically relevant designs that, we argue, should be utilized in the preclinical development phase of new neuroprotective therapies before embarking into clinical trials. Copyright © 2013 Movement Disorders Society.

  19. The therapeutic potential of cannabinoids for movement disorders.

    PubMed

    Kluger, Benzi; Triolo, Piera; Jones, Wallace; Jankovic, Joseph

    2015-03-01

    There is growing interest in the therapeutic potential of marijuana (cannabis) and cannabinoid-based chemicals within the medical community and, particularly, for neurological conditions. This interest is driven both by changes in the legal status of cannabis in many areas and increasing research into the roles of endocannabinoids within the central nervous system and their potential as symptomatic and/or neuroprotective therapies. We review basic science as well as preclinical and clinical studies on the therapeutic potential of cannabinoids specifically as it relates to movement disorders. The pharmacology of cannabis is complex, with over 60 neuroactive chemicals identified to date. The endocannabinoid system modulates neurotransmission involved in motor function, particularly within the basal ganglia. Preclinical research in animal models of several movement disorders have shown variable evidence for symptomatic benefits, but more consistently suggest potential neuroprotective effects in several animal models of Parkinson's (PD) and Huntington's disease (HD). Clinical observations and clinical trials of cannabinoid-based therapies suggests a possible benefit of cannabinoids for tics and probably no benefit for tremor in multiple sclerosis or dyskinesias or motor symptoms in PD. Data are insufficient to draw conclusions regarding HD, dystonia, or ataxia and nonexistent for myoclonus or RLS. Despite the widespread publicity about the medical benefits of cannabinoids, further preclinical and clinical research is needed to better characterize the pharmacological, physiological, and therapeutic effects of this class of drugs in movement disorders. © 2015 International Parkinson and Movement Disorder Society.

  20. Animal Models of Ebolavirus Infection

    PubMed Central

    Claire, Marisa C St; Ragland, Dan R; Bollinger, Laura; Jahrling, Peter B

    2017-01-01

    Ebola virus is a highly pathogenic member of the family Filoviridae that causes a severe hemorrhagic disease in humans and NHP. The 2013–2016 West African outbreak has increased interest in the development and refinement of animal models of Ebola virus disease. These models are used to test countermeasures and vaccines, gain scientific insights into the mechanisms of disease progression and transmission, and study key correlates of immunology. Ebola virus is classified as a BSL4 pathogen and Category A agent, for which the United States government requires preparedness in case of bioterrorism. Rodents, such as Syrian golden hamsters (Mesocricetus auratus), mice (Mus musculus), and guinea pigs (Cavia porcellus), are the most common research species. However, NHP, especially macaques, are favored for Ebola virus disease research due to similarities with humans regarding the pathogenesis, clinical presentation, laboratory findings, and causes of fatality. To satisfy the regulatory requirements for approval of countermeasures against high-consequence pathogens, the FDA instituted the Animal Rule, which permits efficacy studies in animal models in place of human clinical data when such studies are not feasible or ethical. This review provides a comprehensive summary of various animal models and their use in Ebola virus disease research. PMID:28662754

  1. 9 CFR 85.9 - Other interstate movements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Other interstate movements. 85.9 Section 85.9 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS PSEUDORABIES § 85.9...

  2. Movement ecology: size-specific behavioral response of an invasive snail to food availability.

    PubMed

    Snider, Sunny B; Gilliam, James F

    2008-07-01

    movement and enhance our ability to accurately model ecological processes that depend on animal movement.

  3. 9 CFR 72.7 - Interstate movement of cattle from cooperating States.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement of cattle from cooperating States. 72.7 Section 72.7 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... (SPLENETIC) FEVER IN CATTLE § 72.7 Interstate movement of cattle from cooperating States. Cattle in areas...

  4. Animal Models for HIV Cure Research.

    PubMed

    Policicchio, Benjamin B; Pandrea, Ivona; Apetrei, Cristian

    2016-01-01

    The HIV-1/AIDS pandemic continues to spread unabated worldwide, and no vaccine exists within our grasp. Effective antiretroviral therapy (ART) has been developed, but ART cannot clear the virus from the infected patient. A cure for HIV-1 is badly needed to stop both the spread of the virus in human populations and disease progression in infected individuals. A safe and effective cure strategy for human immunodeficiency virus (HIV) infection will require multiple tools, and appropriate animal models are tools that are central to cure research. An ideal animal model should recapitulate the essential aspects of HIV pathogenesis and associated immune responses, while permitting invasive studies, thus allowing a thorough evaluation of strategies aimed at reducing the size of the reservoir (functional cure) or eliminating the reservoir altogether (sterilizing cure). Since there is no perfect animal model for cure research, multiple models have been tailored and tested to address specific quintessential questions of virus persistence and eradication. The development of new non-human primate and mouse models, along with a certain interest in the feline model, has the potential to fuel cure research. In this review, we highlight the major animal models currently utilized for cure research and the contributions of each model to this goal.

  5. Animal Models for HIV Cure Research

    PubMed Central

    Policicchio, Benjamin B.; Pandrea, Ivona; Apetrei, Cristian

    2016-01-01

    The HIV-1/AIDS pandemic continues to spread unabated worldwide, and no vaccine exists within our grasp. Effective antiretroviral therapy (ART) has been developed, but ART cannot clear the virus from the infected patient. A cure for HIV-1 is badly needed to stop both the spread of the virus in human populations and disease progression in infected individuals. A safe and effective cure strategy for human immunodeficiency virus (HIV) infection will require multiple tools, and appropriate animal models are tools that are central to cure research. An ideal animal model should recapitulate the essential aspects of HIV pathogenesis and associated immune responses, while permitting invasive studies, thus allowing a thorough evaluation of strategies aimed at reducing the size of the reservoir (functional cure) or eliminating the reservoir altogether (sterilizing cure). Since there is no perfect animal model for cure research, multiple models have been tailored and tested to address specific quintessential questions of virus persistence and eradication. The development of new non-human primate and mouse models, along with a certain interest in the feline model, has the potential to fuel cure research. In this review, we highlight the major animal models currently utilized for cure research and the contributions of each model to this goal. PMID:26858716

  6. Temporal variation and scale in movement-based resource selection functions

    USGS Publications Warehouse

    Hooten, M.B.; Hanks, E.M.; Johnson, D.S.; Alldredge, M.W.

    2013-01-01

    A common population characteristic of interest in animal ecology studies pertains to the selection of resources. That is, given the resources available to animals, what do they ultimately choose to use? A variety of statistical approaches have been employed to examine this question and each has advantages and disadvantages with respect to the form of available data and the properties of estimators given model assumptions. A wealth of high resolution telemetry data are now being collected to study animal population movement and space use and these data present both challenges and opportunities for statistical inference. We summarize traditional methods for resource selection and then describe several extensions to deal with measurement uncertainty and an explicit movement process that exists in studies involving high-resolution telemetry data. Our approach uses a correlated random walk movement model to obtain temporally varying use and availability distributions that are employed in a weighted distribution context to estimate selection coefficients. The temporally varying coefficients are then weighted by their contribution to selection and combined to provide inference at the population level. The result is an intuitive and accessible statistical procedure that uses readily available software and is computationally feasible for large datasets. These methods are demonstrated using data collected as part of a large-scale mountain lion monitoring study in Colorado, USA.

  7. 9 CFR 93.509 - Movement from conveyances to quarantine station.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Movement from conveyances to... PRODUCTS; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Swine § 93.509 Movement from... fresh products. When movement of the aforesaid swine upon or across a public highway is unavoidable, it...

  8. Art In Movement: New Directions in Animation.

    ERIC Educational Resources Information Center

    Halas, John; Manvell, Roger

    Thanks to film, graphic artists can now create over time as well as in space. An essay discusses the influence of cinema on still paintings (e.g., Duchamp's "Nude Descending a Staircase" and the increasing combination of animation and live action in films. New techniques that are available in animation and in special visual effects are explained,…

  9. Ethical guidelines, animal profile, various animal models used in periodontal research with alternatives and future perspectives.

    PubMed

    Pasupuleti, Mohan Kumar; Molahally, Subramanya Shetty; Salwaji, Supraja

    2016-01-01

    Laboratory animal models serve as a facilitator to investigate the etiopathogenesis of periodontal disease, are used to know the efficacy of reconstructive and regenerative procedures, and are also helpful in evaluation of newer therapeutic techniques including laser and implant therapies prior to application in the human beings. The aim of this review is to know the different animal models used in various specialties of dental research and to know the ethical guidelines prior to the usage of experimental models with main emphasis on how to refine, replace, and reduce the number of animal models usage in the laboratory. An online search for experimental animal models used in dental research was performed using MEDLINE/PubMed database. Publications from 2009 to May 2013 in the specialty of periodontics were included in writing this review. A total of 652 references were published in PubMed/MEDLINE databases based on the search terms used. Out of 245 studies, 241 were related to the periodontal research published in English from 2009 to 2013. Relevant papers were chosen according to the inclusion and exclusion criteria. After extensive electronic and hand search on animal models, it has been observed that various animal models were used in dental research. Search on animal models used for dental research purpose revealed that various animals such as rats, mice, guinea pigs, rabbit, beagle dogs, goats, and nonhuman primates were extensively used. However, with the new advancement of ex vivo animal models, it has become easy to investigate disease pathogenesis and to test the efficacy of newer therapeutic modalities with the reduced usage of animal models. This review summarized the large amount of literature on animal models used in periodontal research with main emphasis on ethical guidelines and on reducing the animal model usage in future perspective.

  10. Ethical guidelines, animal profile, various animal models used in periodontal research with alternatives and future perspectives

    PubMed Central

    Pasupuleti, Mohan Kumar; Molahally, Subramanya Shetty; Salwaji, Supraja

    2016-01-01

    Laboratory animal models serve as a facilitator to investigate the etiopathogenesis of periodontal disease, are used to know the efficacy of reconstructive and regenerative procedures, and are also helpful in evaluation of newer therapeutic techniques including laser and implant therapies prior to application in the human beings. The aim of this review is to know the different animal models used in various specialties of dental research and to know the ethical guidelines prior to the usage of experimental models with main emphasis on how to refine, replace, and reduce the number of animal models usage in the laboratory. An online search for experimental animal models used in dental research was performed using MEDLINE/PubMed database. Publications from 2009 to May 2013 in the specialty of periodontics were included in writing this review. A total of 652 references were published in PubMed/MEDLINE databases based on the search terms used. Out of 245 studies, 241 were related to the periodontal research published in English from 2009 to 2013. Relevant papers were chosen according to the inclusion and exclusion criteria. After extensive electronic and hand search on animal models, it has been observed that various animal models were used in dental research. Search on animal models used for dental research purpose revealed that various animals such as rats, mice, guinea pigs, rabbit, beagle dogs, goats, and nonhuman primates were extensively used. However, with the new advancement of ex vivo animal models, it has become easy to investigate disease pathogenesis and to test the efficacy of newer therapeutic modalities with the reduced usage of animal models. This review summarized the large amount of literature on animal models used in periodontal research with main emphasis on ethical guidelines and on reducing the animal model usage in future perspective. PMID:28298815

  11. Power and Vision: Group-Process Models Evolving from Social-Change Movements.

    ERIC Educational Resources Information Center

    Morrow, Susan L.; Hawxhurst, Donna M.

    1988-01-01

    Explores evolution of group process in social change movements, including the evolution of the new left, the cooperative movement,and the women's liberation movement. Proposes a group-process model that encourages people to share power and live their visions. (Author/NB)

  12. Animal Models of Subjective Tinnitus

    PubMed Central

    2014-01-01

    Tinnitus is one of the major audiological diseases, affecting a significant portion of the ageing society. Despite its huge personal and presumed economic impact there are only limited therapeutic options available. The reason for this deficiency lies in the very nature of the disease as it is deeply connected to elementary plasticity of auditory processing in the central nervous system. Understanding these mechanisms is essential for developing a therapy that reverses the plastic changes underlying the pathogenesis of tinnitus. This requires experiments that address individual neurons and small networks, something usually not feasible in human patients. However, in animals such invasive experiments on the level of single neurons with high spatial and temporal resolution are possible. Therefore, animal models are a very critical element in the combined efforts for engineering new therapies. This review provides an overview over the most important features of animal models of tinnitus: which laboratory species are suitable, how to induce tinnitus, and how to characterize the perceived tinnitus by behavioral means. In particular, these aspects of tinnitus animal models are discussed in the light of transferability to the human patients. PMID:24829805

  13. Understanding eye movements in face recognition using hidden Markov models.

    PubMed

    Chuk, Tim; Chan, Antoni B; Hsiao, Janet H

    2014-09-16

    We use a hidden Markov model (HMM) based approach to analyze eye movement data in face recognition. HMMs are statistical models that are specialized in handling time-series data. We conducted a face recognition task with Asian participants, and model each participant's eye movement pattern with an HMM, which summarized the participant's scan paths in face recognition with both regions of interest and the transition probabilities among them. By clustering these HMMs, we showed that participants' eye movements could be categorized into holistic or analytic patterns, demonstrating significant individual differences even within the same culture. Participants with the analytic pattern had longer response times, but did not differ significantly in recognition accuracy from those with the holistic pattern. We also found that correct and wrong recognitions were associated with distinctive eye movement patterns; the difference between the two patterns lies in the transitions rather than locations of the fixations alone. © 2014 ARVO.

  14. Small Animal Models for Evaluating Filovirus Countermeasures.

    PubMed

    Banadyga, Logan; Wong, Gary; Qiu, Xiangguo

    2018-05-11

    The development of novel therapeutics and vaccines to treat or prevent disease caused by filoviruses, such as Ebola and Marburg viruses, depends on the availability of animal models that faithfully recapitulate clinical hallmarks of disease as it is observed in humans. In particular, small animal models (such as mice and guinea pigs) are historically and frequently used for the primary evaluation of antiviral countermeasures, prior to testing in nonhuman primates, which represent the gold-standard filovirus animal model. In the past several years, however, the filovirus field has witnessed the continued refinement of the mouse and guinea pig models of disease, as well as the introduction of the hamster and ferret models. We now have small animal models for most human-pathogenic filoviruses, many of which are susceptible to wild type virus and demonstrate key features of disease, including robust virus replication, coagulopathy, and immune system dysfunction. Although none of these small animal model systems perfectly recapitulates Ebola virus disease or Marburg virus disease on its own, collectively they offer a nearly complete set of tools in which to carry out the preclinical development of novel antiviral drugs.

  15. Age-Related Changes in Centripetal Ciliary Body Movement Relative to Centripetal Lens Movement in Monkeys

    PubMed Central

    Croft, Mary Ann; McDonald, Jared P.; Nadkarni, Nivedita V.; Lin, Ting-Li; Kaufman, Paul L.

    2009-01-01

    The goal was to determine the age-related changes in accommodative movements of the lens and ciliary body in rhesus monkeys. Varying levels of accommodation were stimulated via the Edinger-Westphal (E-W) nucleus in 26 rhesus monkeys, aged 6-27 years, and the refractive changes were measured by coincidence refractometry. Centripetal ciliary process (CP) and lens movements were measured by computerized image analysis of goniovideographic images. Ultrasound biomicroscopy (UBM) at 50 MHz was used to visualize and measure accommodative forward movements of the ciliary body in relation to age, accommodative amplitude, and centripetal CP and lens movements. At ∼3 diopters of accommodation, the amount of centripetal lens movement required did not significantly change with age (p=0.10; n=18 monkeys); however, the amount of centripetal CP movement required significantly increased with age (p=0.01; n=18 monkeys), while the amount of forward ciliary body movement significantly decreased with age (p=0.007; n=11 monkeys). In the middle-aged animals (12-16.5 years), a greater amount of centripetal CP movement was required to induce a given level of lens movement and thereby a given level of accommodation (p=0.01), compared to the young animals (6-10 yrs). Collectively, the data suggests that, with age, the accommodative system may be attempting to compensate for the loss of forward ciliary body movement by increasing the amount of centripetal CP movement. This, in turn, would allow enough zonular relaxation to achieve the magnitude of centripetal lens movement necessary for a given amplitude of accommodation. PMID:19635475

  16. Animal models of external traumatic wound infections

    PubMed Central

    Dai, Tianhong; Kharkwal, Gitika B; Tanaka, Masamitsu; Huang, Ying-Ying; Bil de Arce, Vida J

    2011-01-01

    Background: Despite advances in traumatic wound care and management, infections remain a leading cause of mortality, morbidity and economic disruption in millions of wound patients around the world. Animal models have become standard tools for studying a wide array of external traumatic wound infections and testing new antimicrobial strategies. Results: Animal models of external traumatic wound infections reported by different investigators vary in animal species used, microorganism strains, the number of microorganisms applied, the size of the wounds and for burn infections, the length of time the heated object or liquid is in contact with the skin. Methods: This review covers experimental infections in animal models of surgical wounds, skin abrasions, burns, lacerations, excisional wounds and open fractures. Conclusions: As antibiotic resistance continues to increase, more new antimicrobial approaches are urgently needed. These should be tested using standard protocols for infections in external traumatic wounds in animal models. PMID:21701256

  17. Effects of some antipsychotics and a benzodiazepine hypnotic on the sleep-wake pattern in an animal model of schizophrenia.

    PubMed

    Ishida, Takayuki; Obara, Yoshihito; Kamei, Chiaki

    2009-09-01

    We studied the effects of antipsychotics and a hypnotic on sleep disturbance in schizophrenia using an animal model of the disease. Electrodes for the electroencephalogram (EEG) and electromyogram (EMG) were chronically implanted into the cortex and the dorsal neck muscle of rats. EEG and EMG were recorded with an electroencephalograph for 6 h (10:00 - 16:00). SleepSign ver. 2.0 was used for EEG and EMG analysis. Haloperidol and olanzapine had an antagonizing effect on the increases in sleep latency and total awake time and the decrease in total non-rapid eye movement (NREM) sleep time induced by MK-801. Olanzapine also antagonized the decrease in total rapid eye movement (REM) sleep time induced by MK-801. Aripiprazole antagonized only the increase in sleep latency induced by MK-801, whereas, risperidone, quetiapine, and flunitrazepam had no effect in the changes of sleep-wake pattern induced by MK-801. Olanzapine increased delta activity and decreased beta activity during NREM sleep. In contrast, flunitrazepam had an opposite effect. It was clarified that haloperidol and olanzapine were effective for decrease of sleep time in this animal model of schizophrenia. In addition, aripiprazole showed a sleep-inducing effect in schizophrenia model rat. On the other hand, flunitrazepam showed no beneficial effect on sleep disturbance in schizophrenia model rat.

  18. Animation control of surface motion capture.

    PubMed

    Tejera, Margara; Casas, Dan; Hilton, Adrian

    2013-12-01

    Surface motion capture (SurfCap) of actor performance from multiple view video provides reconstruction of the natural nonrigid deformation of skin and clothing. This paper introduces techniques for interactive animation control of SurfCap sequences which allow the flexibility in editing and interactive manipulation associated with existing tools for animation from skeletal motion capture (MoCap). Laplacian mesh editing is extended using a basis model learned from SurfCap sequences to constrain the surface shape to reproduce natural deformation. Three novel approaches for animation control of SurfCap sequences, which exploit the constrained Laplacian mesh editing, are introduced: 1) space–time editing for interactive sequence manipulation; 2) skeleton-driven animation to achieve natural nonrigid surface deformation; and 3) hybrid combination of skeletal MoCap driven and SurfCap sequence to extend the range of movement. These approaches are combined with high-level parametric control of SurfCap sequences in a hybrid surface and skeleton-driven animation control framework to achieve natural surface deformation with an extended range of movement by exploiting existing MoCap archives. Evaluation of each approach and the integrated animation framework are presented on real SurfCap sequences for actors performing multiple motions with a variety of clothing styles. Results demonstrate that these techniques enable flexible control for interactive animation with the natural nonrigid surface dynamics of the captured performance and provide a powerful tool to extend current SurfCap databases by incorporating new motions from MoCap sequences.

  19. Transferring of speech movements from video to 3D face space.

    PubMed

    Pei, Yuru; Zha, Hongbin

    2007-01-01

    We present a novel method for transferring speech animation recorded in low quality videos to high resolution 3D face models. The basic idea is to synthesize the animated faces by an interpolation based on a small set of 3D key face shapes which span a 3D face space. The 3D key shapes are extracted by an unsupervised learning process in 2D video space to form a set of 2D visemes which are then mapped to the 3D face space. The learning process consists of two main phases: 1) Isomap-based nonlinear dimensionality reduction to embed the video speech movements into a low-dimensional manifold and 2) K-means clustering in the low-dimensional space to extract 2D key viseme frames. Our main contribution is that we use the Isomap-based learning method to extract intrinsic geometry of the speech video space and thus to make it possible to define the 3D key viseme shapes. To do so, we need only to capture a limited number of 3D key face models by using a general 3D scanner. Moreover, we also develop a skull movement recovery method based on simple anatomical structures to enhance 3D realism in local mouth movements. Experimental results show that our method can achieve realistic 3D animation effects with a small number of 3D key face models.

  20. An extensible simulation environment and movement metrics for testing walking behavior in agent-based models

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

    Paul M. Torrens; Atsushi Nara; Xun Li

    2012-01-01

    Human movement is a significant ingredient of many social, environmental, and technical systems, yet the importance of movement is often discounted in considering systems complexity. Movement is commonly abstracted in agent-based modeling (which is perhaps the methodological vehicle for modeling complex systems), despite the influence of movement upon information exchange and adaptation in a system. In particular, agent-based models of urban pedestrians often treat movement in proxy form at the expense of faithfully treating movement behavior with realistic agency. There exists little consensus about which method is appropriate for representing movement in agent-based schemes. In this paper, we examine popularly-usedmore » methods to drive movement in agent-based models, first by introducing a methodology that can flexibly handle many representations of movement at many different scales and second, introducing a suite of tools to benchmark agent movement between models and against real-world trajectory data. We find that most popular movement schemes do a relatively poor job of representing movement, but that some schemes may well be 'good enough' for some applications. We also discuss potential avenues for improving the representation of movement in agent-based frameworks.« less

  1. Social defeat models in animal science: What we have learned from rodent models.

    PubMed

    Toyoda, Atsushi

    2017-07-01

    Studies on stress and its impacts on animals are very important in many fields of science, including animal science, because various stresses influence animal production and animal welfare. In particular, the social stresses within animal groups have profound impact on animals, with the potential to induce abnormal behaviors and health problems. In humans, social stress induces several health problems, including psychiatric disorders. In animal stress models, social defeat models are well characterized and used in various research fields, particularly in studies concerning mental disorders. Recently, we have focused on behavior, nutrition and metabolism in rodent models of social defeat to elucidate how social stresses affect animals. In this review, recent significant progress in studies related to animal social defeat models are described. In the field of animal science, these stress models may contribute to advances in the development of functional foods and in the management of animal welfare. © 2017 The Authors. Animal Science Journal published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Animal Science.

  2. Current status: Animal models of nausea

    NASA Technical Reports Server (NTRS)

    Fox, Robert A.

    1991-01-01

    The advantages, and possible benefits of a valid, reliable animal model for nausea are discussed, and difficulties inherent to the development of a model are considered. A principle problem for developing models arises because nausea is a subjective sensation that can be identified only in humans. Several putative measures of nausea in animals are considered, with more detailed consideration directed to variation in cardiac rate, levels of vasopressin, and conditioned taste aversion. Demonstration that putative measures are associated with reported nausea in humans is proposed as a requirement for validating measures to be used in animal models. The necessity for a 'real-time' measure of nausea is proposed as an important factor for future research; and the need for improved understanding of the neuroanatomy underlying the emetic syndrome is discussed.

  3. Quantitative model of transport-aperture coordination during reach-to-grasp movements.

    PubMed

    Rand, Miya K; Shimansky, Y P; Hossain, Abul B M I; Stelmach, George E

    2008-06-01

    It has been found in our previous studies that the initiation of aperture closure during reach-to-grasp movements occurs when the hand distance to target crosses a threshold that is a function of peak aperture amplitude, hand velocity, and hand acceleration. Thus, a stable relationship between those four movement parameters is observed at the moment of aperture closure initiation. Based on the concept of optimal control of movements (Naslin 1969) and its application for reach-to-grasp movement regulation (Hoff and Arbib 1993), it was hypothesized that the mathematical equation expressing that relationship can be generalized to describe coordination between hand transport and finger aperture during the entire reach-to-grasp movement by adding aperture velocity and acceleration to the above four movement parameters. The present study examines whether this hypothesis is supported by the data obtained in experiments in which young adults performed reach-to-grasp movements in eight combinations of two reach-amplitude conditions and four movement-speed conditions. It was found that linear approximation of the mathematical model described the relationship among the six movement parameters for the entire aperture-closure phase with very high precision for each condition, thus supporting the hypothesis for that phase. Testing whether one mathematical model could approximate the data across all the experimental conditions revealed that it was possible to achieve the same high level of data-fitting precision only by including in the model two additional, condition-encoding parameters and using a nonlinear, artificial neural network-based approximator with two hidden layers comprising three and two neurons, respectively. This result indicates that transport-aperture coordination, as a specific relationship between the parameters of hand transport and finger aperture, significantly depends on the condition-encoding variables. The data from the aperture-opening phase also fit a

  4. Animal Models in Cardiovascular Research: Hypertension and Atherosclerosis

    PubMed Central

    Ng, Chun-Yi; Jaarin, Kamsiah

    2015-01-01

    Hypertension and atherosclerosis are among the most common causes of mortality in both developed and developing countries. Experimental animal models of hypertension and atherosclerosis have become a valuable tool for providing information on etiology, pathophysiology, and complications of the disease and on the efficacy and mechanism of action of various drugs and compounds used in treatment. An animal model has been developed to study hypertension and atherosclerosis for several reasons. Compared to human models, an animal model is easily manageable, as compounding effects of dietary and environmental factors can be controlled. Blood vessels and cardiac tissue samples can be taken for detailed experimental and biomolecular examination. Choice of animal model is often determined by the research aim, as well as financial and technical factors. A thorough understanding of the animal models used and complete analysis must be validated so that the data can be extrapolated to humans. In conclusion, animal models for hypertension and atherosclerosis are invaluable in improving our understanding of cardiovascular disease and developing new pharmacological therapies. PMID:26064920

  5. Osteoarthritis: new insights in animal models.

    PubMed

    Longo, Umile Giuseppe; Loppini, Mattia; Fumo, Caterina; Rizzello, Giacomo; Khan, Wasim Sardar; Maffulli, Nicola; Denaro, Vincenzo

    2012-01-01

    Osteoarthritis (OA) is the most frequent and symptomatic health problem in the middle-aged and elderly population, with over one-half of all people over the age of 65 showing radiographic changes in painful knees. The aim of the present study was to perform an overview on the available animal models used in the research field on the OA. Discrepancies between the animal models and the human disease are present. As regards human 'idiopathic' OA, with late onset and slow progression, it is perhaps wise not to be overly enthusiastic about animal models that show severe chondrodysplasia and very early OA. Advantage by using genetically engineered mouse models, in comparison with other surgically induced models, is that molecular etiology is known. Find potential molecular markers for the onset of the disease and pay attention to the role of gender and environmental factors should be very helpful in the study of mice that acquire premature OA. Surgically induced destabilization of joint is the most widely used induction method. These models allow the temporal control of disease induction and follow predictable progression of the disease. In animals, ACL transection and meniscectomy show a speed of onset and severity of disease higher than in humans after same injury.

  6. Animal models of traumatic brain injury

    PubMed Central

    Xiong, Ye; Mahmood, Asim; Chopp, Michael

    2014-01-01

    Traumatic brain injury (TBI) is a leading cause of mortality and morbidity in both civilian life and the battlefield worldwide. Survivors of TBI frequently experience long-term disabling changes in cognition, sensorimotor function and personality. Over the past three decades, animal models have been developed to replicate the various aspects of human TBI, to better understand the underlying pathophysiology and to explore potential treatments. Nevertheless, promising neuroprotective drugs, which were identified to be effective in animal TBI models, have all failed in phase II or phase III clinical trials. This failure in clinical translation of preclinical studies highlights a compelling need to revisit the current status of animal models of TBI and therapeutic strategies. PMID:23329160

  7. Teaching animal welfare in the land grant universities.

    PubMed

    Friend, T H

    1990-10-01

    Colleges and universities have an obligation to teach the basis of animal husbandry and welfare and must prepare students so that they can respond effectively to challenges by proponents of the animal welfare and animal rights movements. Veterinary curricula must now contain formal instruction in professional ethics and humane stewardship of animals for accreditation by the American Veterinary Medical Association. It is helpful if students have an understanding of farm animal behavior, stress physiology and methods of assessing welfare prior to learning about the animal welfare/rights movement's philosophies and issues. A review of early judicial practices, "classical" Judeo-Christian philosophy, the philosophy of Rene Descartes, Jeremy Bentham, Albert Schweitzer, and current philosophers and the entertainment media places the movements in perspective. Students should be familiar with such concepts as the mind-body controversy, equality of suffering, self-awareness or intelligence, and speciesism. After acquiring an appreciation of the basics, a knowledge of the issues facing animal agriculture and the arguments for and against each issue are necessary. Graduates of colleges of agriculture need to realize the potential effects the movements can have and take the initiative to improve the image of animal agriculture.

  8. Predictive control of intersegmental tarsal movements in an insect.

    PubMed

    Costalago-Meruelo, Alicia; Simpson, David M; Veres, Sandor M; Newland, Philip L

    2017-08-01

    In many animals intersegmental reflexes are important for postural and movement control but are still poorly undesrtood. Mathematical methods can be used to model the responses to stimulation, and thus go beyond a simple description of responses to specific inputs. Here we analyse an intersegmental reflex of the foot (tarsus) of the locust hind leg, which raises the tarsus when the tibia is flexed and depresses it when the tibia is extended. A novel method is described to measure and quantify the intersegmental responses of the tarsus to a stimulus to the femoro-tibial chordotonal organ. An Artificial Neural Network, the Time Delay Neural Network, was applied to understand the properties and dynamics of the reflex responses. The aim of this study was twofold: first to develop an accurate method to record and analyse the movement of an appendage and second, to apply methods to model the responses using Artificial Neural Networks. The results show that Artificial Neural Networks provide accurate predictions of tarsal movement when trained with an average reflex response to Gaussian White Noise stimulation compared to linear models. Furthermore, the Artificial Neural Network model can predict the individual responses of each animal and responses to others inputs such as a sinusoid. A detailed understanding of such a reflex response could be included in the design of orthoses or functional electrical stimulation treatments to improve walking in patients with neurological disorders as well as the bio/inspired design of robots.

  9. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine or...

  10. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine or...

  11. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine or...

  12. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine or...

  13. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine or...

  14. Animal models for microbicide safety and efficacy testing.

    PubMed

    Veazey, Ronald S

    2013-07-01

    Early studies have cast doubt on the utility of animal models for predicting success or failure of HIV-prevention strategies, but results of multiple human phase 3 microbicide trials, and interrogations into the discrepancies between human and animal model trials, indicate that animal models were, and are, predictive of safety and efficacy of microbicide candidates. Recent studies have shown that topically applied vaginal gels, and oral prophylaxis using single or combination antiretrovirals are indeed effective in preventing sexual HIV transmission in humans, and all of these successes were predicted in animal models. Further, prior discrepancies between animal and human results are finally being deciphered as inadequacies in study design in the model, or quite often, noncompliance in human trials, the latter being increasingly recognized as a major problem in human microbicide trials. Successful microbicide studies in humans have validated results in animal models, and several ongoing studies are further investigating questions of tissue distribution, duration of efficacy, and continued safety with repeated application of these, and other promising microbicide candidates in both murine and nonhuman primate models. Now that we finally have positive correlations with prevention strategies and protection from HIV transmission, we can retrospectively validate animal models for their ability to predict these results, and more importantly, prospectively use these models to select and advance even safer, more effective, and importantly, more durable microbicide candidates into human trials.

  15. Startle stimuli reduce the internal model control in discrete movements.

    PubMed

    Wright, Zachary A; Rogers, Mark W; MacKinnon, Colum D; Patton, James L

    2009-01-01

    A well known and major component of movement control is the feedforward component, also known as the internal model. This model predicts and compensates for expected forces seen during a movement, based on recent experience, so that a well-learned task such as reaching to a target can be executed in a smooth straight manner. It has recently been shown that the state of preparation of planned movements can be tested using a startling acoustic stimulus (SAS). SAS, presented 500, 250 or 0 ms before the expected "go" cue resulted in the early release of the movement trajectory associated with the after-effects of the force field training (i.e. the internal model). In a typical motor adaptation experiment with a robot-applied force field, we tested if a SAS stimulus influences the size of after-effects that are typically seen. We found that in all subjects the after-effect magnitudes were significantly reduced when movements were released by SAS, although this effect was not further modulated by the timing of SAS. Reduced after-effects reveal at least partial existence of learned preparatory control, and identify startle effects that could influence performance in tasks such as piloting, teleoperation, and sports.

  16. Bridging Animal and Human Models

    PubMed Central

    Barkley-Levenson, Amanda M.; Crabbe, John C.

    2012-01-01

    Genetics play an important role in the development and course of alcohol abuse, and understanding genetic contributions to this disorder may lead to improved preventative and therapeutic strategies in the future. Studies both in humans and in animal models are necessary to fully understand the neurobiology of alcoholism from the molecular to the cognitive level. By dissecting the complex facets of alcoholism into discrete, well-defined phenotypes that are measurable in both human populations and animal models of the disease, researchers will be better able to translate findings across species and integrate the knowledge obtained from various disciplines. Some of the key areas of alcoholism research where consilience between human and animal studies is possible are alcohol withdrawal severity, sensitivity to rewards, impulsivity, and dysregulated alcohol consumption. PMID:23134048

  17. Moving in the Anthropocene: Global reductions in terrestrial mammalian movements.

    PubMed

    Tucker, Marlee A; Böhning-Gaese, Katrin; Fagan, William F; Fryxell, John M; Van Moorter, Bram; Alberts, Susan C; Ali, Abdullahi H; Allen, Andrew M; Attias, Nina; Avgar, Tal; Bartlam-Brooks, Hattie; Bayarbaatar, Buuveibaatar; Belant, Jerrold L; Bertassoni, Alessandra; Beyer, Dean; Bidner, Laura; van Beest, Floris M; Blake, Stephen; Blaum, Niels; Bracis, Chloe; Brown, Danielle; de Bruyn, P J Nico; Cagnacci, Francesca; Calabrese, Justin M; Camilo-Alves, Constança; Chamaillé-Jammes, Simon; Chiaradia, Andre; Davidson, Sarah C; Dennis, Todd; DeStefano, Stephen; Diefenbach, Duane; Douglas-Hamilton, Iain; Fennessy, Julian; Fichtel, Claudia; Fiedler, Wolfgang; Fischer, Christina; Fischhoff, Ilya; Fleming, Christen H; Ford, Adam T; Fritz, Susanne A; Gehr, Benedikt; Goheen, Jacob R; Gurarie, Eliezer; Hebblewhite, Mark; Heurich, Marco; Hewison, A J Mark; Hof, Christian; Hurme, Edward; Isbell, Lynne A; Janssen, René; Jeltsch, Florian; Kaczensky, Petra; Kane, Adam; Kappeler, Peter M; Kauffman, Matthew; Kays, Roland; Kimuyu, Duncan; Koch, Flavia; Kranstauber, Bart; LaPoint, Scott; Leimgruber, Peter; Linnell, John D C; López-López, Pascual; Markham, A Catherine; Mattisson, Jenny; Medici, Emilia Patricia; Mellone, Ugo; Merrill, Evelyn; de Miranda Mourão, Guilherme; Morato, Ronaldo G; Morellet, Nicolas; Morrison, Thomas A; Díaz-Muñoz, Samuel L; Mysterud, Atle; Nandintsetseg, Dejid; Nathan, Ran; Niamir, Aidin; Odden, John; O'Hara, Robert B; Oliveira-Santos, Luiz Gustavo R; Olson, Kirk A; Patterson, Bruce D; Cunha de Paula, Rogerio; Pedrotti, Luca; Reineking, Björn; Rimmler, Martin; Rogers, Tracey L; Rolandsen, Christer Moe; Rosenberry, Christopher S; Rubenstein, Daniel I; Safi, Kamran; Saïd, Sonia; Sapir, Nir; Sawyer, Hall; Schmidt, Niels Martin; Selva, Nuria; Sergiel, Agnieszka; Shiilegdamba, Enkhtuvshin; Silva, João Paulo; Singh, Navinder; Solberg, Erling J; Spiegel, Orr; Strand, Olav; Sundaresan, Siva; Ullmann, Wiebke; Voigt, Ulrich; Wall, Jake; Wattles, David; Wikelski, Martin; Wilmers, Christopher C; Wilson, John W; Wittemyer, George; Zięba, Filip; Zwijacz-Kozica, Tomasz; Mueller, Thomas

    2018-01-26

    Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission. Copyright © 2018, The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  18. Animal models for dengue vaccine development and testing

    PubMed Central

    2017-01-01

    Dengue fever is a tropical endemic disease; however, because of climate change, it may become a problem in South Korea in the near future. Research on vaccines for dengue fever and outbreak preparedness are currently insufficient. In addition, because there are no appropriate animal models, controversial results from vaccine efficacy assessments and clinical trials have been reported. Therefore, to study the mechanism of dengue fever and test the immunogenicity of vaccines, an appropriate animal model is urgently needed. In addition to mouse models, more suitable models using animals that can be humanized will need to be constructed. In this report, we look at the current status of model animal construction and discuss which models require further development. PMID:28775974

  19. Animal models for dengue vaccine development and testing.

    PubMed

    Na, Woonsung; Yeom, Minjoo; Choi, Il-Kyu; Yook, Heejun; Song, Daesub

    2017-07-01

    Dengue fever is a tropical endemic disease; however, because of climate change, it may become a problem in South Korea in the near future. Research on vaccines for dengue fever and outbreak preparedness are currently insufficient. In addition, because there are no appropriate animal models, controversial results from vaccine efficacy assessments and clinical trials have been reported. Therefore, to study the mechanism of dengue fever and test the immunogenicity of vaccines, an appropriate animal model is urgently needed. In addition to mouse models, more suitable models using animals that can be humanized will need to be constructed. In this report, we look at the current status of model animal construction and discuss which models require further development.

  20. Allometric and temporal scaling of movement characteristics in Galapagos tortoises.

    PubMed

    Bastille-Rousseau, Guillaume; Yackulic, Charles B; Frair, Jacqueline L; Cabrera, Freddy; Blake, Stephen

    2016-09-01

    Understanding how individual movement scales with body size is of fundamental importance in predicting ecological relationships for diverse species. One-dimensional movement metrics scale consistently with body size yet vary over different temporal scales. Knowing how temporal scale influences the relationship between animal body size and movement would better inform hypotheses about the efficiency of foraging behaviour, the ontogeny of energy budgets, and numerous life-history trade-offs. We investigated how the temporal scaling of allometric patterns in movement varies over the course of a year, specifically during periods of motivated (directional and fast movement) and unmotivated (stationary and tortuous movement) behaviour. We focused on a recently diverged group of species that displays wide variation in movement behaviour - giant Galapagos tortoises (Chelonoidis spp.) - to test how movement metrics estimated on a monthly basis scaled with body size. We used state-space modelling to estimate seven different movement metrics of Galapagos tortoises. We used log-log regression of the power law to evaluate allometric scaling for these movement metrics and contrasted relationships by species and sex. Allometric scaling of movement was more apparent during motivated periods of movement. During this period, allometry was revealed at multiple temporal intervals (hourly, daily and monthly), with values observed at daily and monthly intervals corresponding most closely to the expected one-fourth scaling coefficient, albeit with wide credible intervals. We further detected differences in the magnitude of scaling among taxa uncoupled from observed differences in the temporal structuring of their movement rates. Our results indicate that the definition of temporal scales is fundamental to the detection of allometry of movement and should be given more attention in movement studies. Our approach not only provides new conceptual insights into temporal attributes in one

  1. Feed-forward motor control of ultrafast, ballistic movements.

    PubMed

    Kagaya, K; Patek, S N

    2016-02-01

    To circumvent the limits of muscle, ultrafast movements achieve high power through the use of springs and latches. The time scale of these movements is too short for control through typical neuromuscular mechanisms, thus ultrafast movements are either invariant or controlled prior to movement. We tested whether mantis shrimp (Stomatopoda: Neogonodactylus bredini) vary their ultrafast smashing strikes and, if so, how this control is achieved prior to movement. We collected high-speed images of strike mechanics and electromyograms of the extensor and flexor muscles that control spring compression and latch release. During spring compression, lateral extensor and flexor units were co-activated. The strike initiated several milliseconds after the flexor units ceased, suggesting that flexor activity prevents spring release and determines the timing of strike initiation. We used linear mixed models and Akaike's information criterion to serially evaluate multiple hypotheses for control mechanisms. We found that variation in spring compression and strike angular velocity were statistically explained by spike activity of the extensor muscle. The results show that mantis shrimp can generate kinematically variable strikes and that their kinematics can be changed through adjustments to motor activity prior to the movement, thus supporting an upstream, central-nervous-system-based control of ultrafast movement. Based on these and other findings, we present a shishiodoshi model that illustrates alternative models of control in biological ballistic systems. The discovery of feed-forward control in mantis shrimp sets the stage for the assessment of targets, strategic variation in kinematics and the role of learning in ultrafast animals. © 2016. Published by The Company of Biologists Ltd.

  2. Pain assessment in animal models of osteoarthritis.

    PubMed

    Piel, Margaret J; Kroin, Jeffrey S; van Wijnen, Andre J; Kc, Ranjan; Im, Hee-Jeong

    2014-03-10

    Assessment of pain in animal models of osteoarthritis is integral to interpretation of a model's utility in representing the clinical condition, and enabling accurate translational medicine. Here we describe behavioral pain assessments available for small and large experimental osteoarthritic pain animal models. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Animal models of cardiac cachexia.

    PubMed

    Molinari, Francesca; Malara, Natalia; Mollace, Vincenzo; Rosano, Giuseppe; Ferraro, Elisabetta

    2016-09-15

    Cachexia is the loss of body weight associated with several chronic diseases including chronic heart failure (CHF). The cachectic condition is mainly due to loss of skeletal muscle mass and adipose tissue depletion. The majority of experimental in vivo studies on cachexia rely on animal models of cancer cachexia while a reliable and appropriate model for cardiac cachexia has not yet been established. A critical issue in generating a cardiac cachexia model is that genetic modifications or pharmacological treatments impairing the heart functionality and used to obtain the heart failure model might likely impair the skeletal muscle, this also being a striated muscle and sharing with the myocardium several molecular and physiological mechanisms. On the other hand, often, the induction of heart damage in the several existing models of heart failure does not necessarily lead to skeletal muscle loss and cachexia. Here we describe the main features of cardiac cachexia and illustrate some animal models proposed for cardiac cachexia studies; they include the genetic calsequestrin and Dahl salt-sensitive models, the monocrotaline model and the surgical models obtained by left anterior descending (LAD) ligation, transverse aortic constriction (TAC) and ascending aortic banding. The availability of a specific animal model for cardiac cachexia is a crucial issue since, besides the common aspects of cachexia in the different syndromes, each disease has some peculiarities in its etiology and pathophysiology leading to cachexia. Such peculiarities need to be unraveled in order to find new targets for effective therapies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Model of head-neck joint fast movements in the frontal plane.

    PubMed

    Pedrocchi, A; Ferrigno, G

    2004-06-01

    The objective of this work is to develop a model representing the physiological systems driving fast head movements in frontal plane. All the contributions occurring mechanically in the head movement are considered: damping, stiffness, physiological limit of range of motion, gravitational field, and muscular torques due to voluntary activation as well as to stretch reflex depending on fusal afferences. Model parameters are partly derived from the literature, when possible, whereas undetermined block parameters are determined by optimising the model output, fitting to real kinematics data acquired by a motion capture system in specific experimental set-ups. The optimisation for parameter identification is performed by genetic algorithms. Results show that the model represents very well fast head movements in the whole range of inclination in the frontal plane. Such a model could be proposed as a tool for transforming kinematics data on head movements in 'neural equivalent data', especially for assessing head control disease and properly planning the rehabilitation process. In addition, the use of genetic algorithms seems to fit well the problem of parameter identification, allowing for the use of a very simple experimental set-up and granting model robustness.

  5. Latest animal models for anti-HIV drug discovery.

    PubMed

    Sliva, Katja

    2015-02-01

    HIV research is limited by the fact that lentiviruses are highly species specific. The need for appropriate models to promote research has led to the development of many elaborate surrogate animal models. This review looks at the history of animal models for HIV research. Although natural animal lentivirus infections and chimeric viruses such as chimera between HIV and simian immunodeficiency virus and simian-tropic HIV are briefly discussed, the main focus is on small animal models, including the complex design of the 'humanized' mouse. The review also traces the historic evolution and milestones as well as depicting current models and future prospects for HIV research. HIV research is a complex and challenging task that is highly manpower-, money- and time-consuming. Besides factors such as hypervariability and latency, the lack of appropriate animal models that exhibit and recapitulate the entire infectious process of HIV, is one of the reasons behind the failure to eliminate the lentivirus from the human population. This obstacle has led to the exploitation and further development of many sophisticated surrogate animal models for HIV research. While there is no animal model that perfectly mirrors and mimics HIV infections in humans, there are a variety of host species and viruses that complement each other. Combining the insights from each model, and critically comparing the results obtained with data from human clinical trials should help expand our understanding of HIV pathogenesis and drive future drug development.

  6. Animal models in motion sickness research

    NASA Technical Reports Server (NTRS)

    Daunton, Nancy G.

    1990-01-01

    Practical information on candidate animal models for motion sickness research and on methods used to elicit and detect motion sickness in these models is provided. Four good potential models for use in motion sickness experiments include the dog, cat, squirrel monkey, and rat. It is concluded that the appropriate use of the animal models, combined with exploitation of state-of-the-art biomedical techniques, should generate a great step forward in the understanding of motion sickness mechanisms and in the development of efficient and effective approaches to its prevention and treatment in humans.

  7. Animal models of gastrointestinal and liver diseases. Animal models of cystic fibrosis: gastrointestinal, pancreatic, and hepatobiliary disease and pathophysiology

    PubMed Central

    Olivier, Alicia K.; Gibson-Corley, Katherine N.

    2015-01-01

    Multiple organ systems, including the gastrointestinal tract, pancreas, and hepatobiliary systems, are affected by cystic fibrosis (CF). Many of these changes begin early in life and are difficult to study in young CF patients. Recent development of novel CF animal models has expanded opportunities in the field to better understand CF pathogenesis and evaluate traditional and innovative therapeutics. In this review, we discuss manifestations of CF disease in gastrointestinal, pancreatic, and hepatobiliary systems of humans and animal models. We also compare the similarities and limitations of animal models and discuss future directions for modeling CF. PMID:25591863

  8. Animal Models of Atherosclerosis

    PubMed Central

    Getz, Godfrey S.; Reardon, Catherine A.

    2012-01-01

    Atherosclerosis is a chronic inflammatory disorder that is the underlying cause of most cardiovascular disease. Both cells of the vessel wall and cells of the immune system participate in atherogenesis. This process is heavily influenced by plasma lipoproteins, genetics and the hemodynamics of the blood flow in the artery. A variety of small and large animal models have been used to study the atherogenic process. No model is ideal as each has its own advantages and limitations with respect to manipulation of the atherogenic process and modeling human atherosclerosis or lipoprotein profile. Useful large animal models include pigs, rabbits and non-human primates. Due in large part to the relative ease of genetic manipulation and the relatively short time frame for the development of atherosclerosis, murine models are currently the most extensively used. While not all aspects of murine atherosclerosis are identical to humans, studies using murine models have suggested potential biological processes and interactions that underlie this process. As it becomes clear that different factors may influence different stages of lesion development, the use of mouse models with the ability to turn on or delete proteins or cells in tissue specific and temporal manner will be very valuable. PMID:22383700

  9. Fragmentation of Rapid Eye Movement and Nonrapid Eye Movement Sleep without Total Sleep Loss Impairs Hippocampus-Dependent Fear Memory Consolidation

    PubMed Central

    Lee, Michael L.; Katsuyama, Ângela M.; Duge, Leanne S.; Sriram, Chaitra; Krushelnytskyy, Mykhaylo; Kim, Jeansok J.; de la Iglesia, Horacio O.

    2016-01-01

    Study Objectives: Sleep is important for consolidation of hippocampus-dependent memories. It is hypothesized that the temporal sequence of nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep is critical for the weakening of nonadaptive memories and the subsequent transfer of memories temporarily stored in the hippocampus to more permanent memories in the neocortex. A great body of evidence supporting this hypothesis relies on behavioral, pharmacological, neural, and/or genetic manipulations that induce sleep deprivation or stage-specific sleep deprivation. Methods: We exploit an experimental model of circadian desynchrony in which intact animals are not deprived of any sleep stage but show fragmentation of REM and NREM sleep within nonfragmented sleep bouts. We test the hypothesis that the shortening of NREM and REM sleep durations post-training will impair memory consolidation irrespective of total sleep duration. Results: When circadian-desynchronized animals are trained in a hippocampus-dependent contextual fear-conditioning task they show normal short-term memory but impaired long-term memory consolidation. This impairment in memory consolidation is positively associated with the post-training fragmentation of REM and NREM sleep but is not significantly associated with the fragmentation of total sleep or the total amount of delta activity. We also show that the sleep stage fragmentation resulting from circadian desynchrony has no effect on hippocampus-dependent spatial memory and no effect on hippocampus-independent cued fear-conditioning memory. Conclusions: Our findings in an intact animal model, in which sleep deprivation is not a confounding factor, support the hypothesis that the stereotypic sequence and duration of sleep stages play a specific role in long-term hippocampus-dependent fear memory consolidation. Citation: Lee ML, Katsuyama AM, Duge LS, Sriram C, Krushelnytskyy M, Kim JJ, de la Iglesia HO. Fragmentation of rapid eye movement

  10. Animal models of schizophrenia

    PubMed Central

    Jones, CA; Watson, DJG; Fone, KCF

    2011-01-01

    Developing reliable, predictive animal models for complex psychiatric disorders, such as schizophrenia, is essential to increase our understanding of the neurobiological basis of the disorder and for the development of novel drugs with improved therapeutic efficacy. All available animal models of schizophrenia fit into four different induction categories: developmental, drug-induced, lesion or genetic manipulation, and the best characterized examples of each type are reviewed herein. Most rodent models have behavioural phenotype changes that resemble ‘positive-like’ symptoms of schizophrenia, probably reflecting altered mesolimbic dopamine function, but fewer models also show altered social interaction, and learning and memory impairment, analogous to negative and cognitive symptoms of schizophrenia respectively. The negative and cognitive impairments in schizophrenia are resistant to treatment with current antipsychotics, even after remission of the psychosis, which limits their therapeutic efficacy. The MATRICS initiative developed a consensus on the core cognitive deficits of schizophrenic patients, and recommended a standardized test battery to evaluate them. More recently, work has begun to identify specific rodent behavioural tasks with translational relevance to specific cognitive domains affected in schizophrenia, and where available this review focuses on reporting the effect of current and potential antipsychotics on these tasks. The review also highlights the need to develop more comprehensive animal models that more adequately replicate deficits in negative and cognitive symptoms. Increasing information on the neurochemical and structural CNS changes accompanying each model will also help assess treatments that prevent the development of schizophrenia rather than treating the symptoms, another pivotal change required to enable new more effective therapeutic strategies to be developed. LINKED ARTICLES This article is part of a themed issue on

  11. Rainfall-ground movement modelling for natural gas pipelines through landslide terrain

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

    O`Neil, G.D.; Simmonds, G.R.; Grivas, D.A.

    1996-12-31

    Perhaps the greatest challenge to geotechnical engineers is to maintain the integrity of pipelines at river crossings where landslide terrain dominates the approach slopes. The current design process at NOVA Gas Transmission Ltd. (NGTL) has developed to the point where this impact can be reasonably estimated using in-house models of pipeline-soil interaction. To date, there has been no method to estimate ground movements within unexplored slopes at the outset of the design process. To address this problem, rainfall and slope instrumentation data have been processed to derive rainfall-ground movement relationships. Early results indicate that the ground movements exhibit two components:more » a steady, small rate of movement independent of the rainfall, and, increased rates over short periods of time following heavy amounts of rainfall. Evidence exists of a definite threshold value of rainfall which has to be exceeded before any incremental movement is induced. Additional evidence indicates a one-month lag between rainfall and ground movement. While these models are in the preliminary stage, results indicate a potential to estimate ground movements for both initial design and planned maintenance actions.« less

  12. The necessity of animal models in pain research.

    PubMed

    Mogil, Jeffrey S; Davis, Karen D; Derbyshire, Stuart W

    2010-10-01

    There exists currently a fair degree of introspection in the pain research community about the value of animal research. This review represents a defense of animal research in pain. We discuss the inherent advantage of animal models over human research as well as the crucial complementary roles animal studies play vis-à-vis human imaging and genetic studies. Finally, we discuss recent developments in animal models of pain that should improve the relevance and translatability of findings using laboratory animals. We believe that pain research using animal models is a continuing necessity-to understand fundamental mechanisms, identify new analgesic targets, and inform, guide and follow up human studies-if novel analgesics are to be developed for the treatment of chronic pain. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  13. 9 CFR 85.4 - Interstate movement of livestock.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Interstate movement of livestock. 85.4 Section 85.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS PSEUDORABIES § 85.4...

  14. 9 CFR 85.4 - Interstate movement of livestock.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Interstate movement of livestock. 85.4 Section 85.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS PSEUDORABIES § 85.4...

  15. 9 CFR 85.4 - Interstate movement of livestock.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Interstate movement of livestock. 85.4 Section 85.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS PSEUDORABIES § 85.4...

  16. 9 CFR 85.4 - Interstate movement of livestock.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Interstate movement of livestock. 85.4 Section 85.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS PSEUDORABIES § 85.4...

  17. Acute and Chronic Exercise in Animal Models.

    PubMed

    Thu, Vu Thi; Kim, Hyoung Kyu; Han, Jin

    2017-01-01

    Numerous animal cardiac exercise models using animal subjects have been established to uncover the cardiovascular physiological mechanism of exercise or to determine the effects of exercise on cardiovascular health and disease. In most cases, animal-based cardiovascular exercise modalities include treadmill running, swimming, and voluntary wheel running with a series of intensities, times, and durations. Those used animals include small rodents (e.g., mice and rats) and large animals (e.g., rabbits, dogs, goats, sheep, pigs, and horses). Depending on the research goal, each experimental protocol should also describe whether its respective exercise treatment can produce the anticipated acute or chronic cardiovascular adaptive response. In this chapter, we will briefly describe the most common kinds of animal models of acute and chronic cardiovascular exercises that are currently being conducted and are likely to be chosen in the near future. Strengths and weakness of animal-based cardiac exercise modalities are also discussed.

  18. Modeling of human movement monitoring using Bluetooth Low Energy technology.

    PubMed

    Mokhtari, G; Zhang, Q; Karunanithi, M

    2015-01-01

    Bluetooth Low Energy (BLE) is a wireless communication technology which can be used to monitor human movements. In this monitoring system, a BLE signal scanner scans signal strength of BLE tags carried by people, to thus infer human movement patterns within its monitoring zone. However to the extent of our knowledge one main aspect of this monitoring system which has not yet been thoroughly investigated in literature is how to build a sound theoretical model, based on tunable BLE communication parameters such as scanning time interval and advertising time interval, to enable the study and design of effective and efficient movement monitoring systems. In this paper, we proposed and developed a statistical model based on Monte-Carlo simulation, which can be utilized to assess impacts of BLE technology parameters in terms of latency and efficiency, on a movement monitoring system, and can thus benefit a more efficient system design.

  19. Animal Models of Human Granulocyte Diseases

    PubMed Central

    Schäffer, Alejandro A.; Klein, Christoph

    2012-01-01

    In vivo animal models have proven very useful to understand basic biological pathways of the immune system, a prerequisite for the development of innovate therapies. This manuscript addresses currently available models for defined human monogenetic defects of neutrophil granulocytes, including murine, zebrafish and larger mammalian species. Strengths and weaknesses of each system are summarized, and clinical investigators may thus be inspired to develop further lines of research to improve diagnosis and therapy by use of the appropriate animal model system. PMID:23351993

  20. Bridging the gulf between correlated random walks and Lévy walks: autocorrelation as a source of Lévy walk movement patterns.

    PubMed

    Reynolds, Andy M

    2010-12-06

    For many years, the dominant conceptual framework for describing non-oriented animal movement patterns has been the correlated random walk (CRW) model in which an individual's trajectory through space is represented by a sequence of distinct, independent randomly oriented 'moves'. It has long been recognized that the transformation of an animal's continuous movement path into a broken line is necessarily arbitrary and that probability distributions of move lengths and turning angles are model artefacts. Continuous-time analogues of CRWs that overcome this inherent shortcoming have appeared in the literature and are gaining prominence. In these models, velocities evolve as a Markovian process and have exponential autocorrelation. Integration of the velocity process gives the position process. Here, through a simple scaling argument and through an exact analytical analysis, it is shown that autocorrelation inevitably leads to Lévy walk (LW) movement patterns on timescales less than the autocorrelation timescale. This is significant because over recent years there has been an accumulation of evidence from a variety of experimental and theoretical studies that many organisms have movement patterns that can be approximated by LWs, and there is now intense debate about the relative merits of CRWs and LWs as representations of non-orientated animal movement patterns.

  1. Verification by Remote Sensing of an Oil Slick Movement Prediction Model

    NASA Technical Reports Server (NTRS)

    Klemas, V. (Principal Investigator); Davis, G.; Wang, H.

    1975-01-01

    The author has identified the following significant results. LANDSAT, aircraft, ships, and air-dropped current drogues were deployed to determine current circulation and to track oil slick movement on four different dates in Delaware Bay. Results were used to verify a predictive model for oil slick movement and dispersion. The model predicts the behavior of oil slicks given their size, location, tidal stage (current), weather (wind), and nature of crude. Both LANDSAT satellites provided valuable data on gross circulation patterns and convergent coastal fronts which by capturing oil slicks significantly influence their movement and dispersion.

  2. Low-level laser therapy stimulates bone metabolism and inhibits root resorption during tooth movement in a rodent model.

    PubMed

    Suzuki, Selly Sayuri; Garcez, Aguinaldo Silva; Suzuki, Hideo; Ervolino, Edilson; Moon, Won; Ribeiro, Martha Simões

    2016-12-01

    This study evaluated the biological effects of low-level laser therapy (LLLT) on bone remodeling, tooth displacement and root resorption, occurred during the orthodontic tooth movement. Upper first molars of a total of sixty-eight male rats were subjected to orthodontic tooth movement and euthanized on days 3, 6, 9, 14 and 21 days and divided as negative control, control and LLLT group. Tooth displacement and histomorphometric analysis were performed in all animals; scanning electron microscopy analysis was done on days 3, 6 and 9, as well as the immunohistochemistry analysis of RANKL/OPG and TRAP markers. Volumetric changes in alveolar bone were analyzed using MicroCT images on days 14 and 21. LLLT influenced bone resorption by increasing the number of TRAP-positive osteoclasts and the RANKL expression at the compression side. This resulted in less alveolar bone and hyalinization areas on days 6, 9 and 14. LLLT also induced less bone volume and density, facilitating significant acceleration of tooth movement and potential reduction in root resorption besides stimulating bone formation at the tension side by enhancing OPG expression, increasing trabecular thickness and bone volume on day 21. Taken together, our results indicate that LLLT can stimulate bone remodeling reducing root resorption in a rat model. LLLT improves tooth movement via bone formation and bone resorption in a rat model. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Hierarchical models of animal abundance and occurrence

    USGS Publications Warehouse

    Royle, J. Andrew; Dorazio, R.M.

    2006-01-01

    Much of animal ecology is devoted to studies of abundance and occurrence of species, based on surveys of spatially referenced sample units. These surveys frequently yield sparse counts that are contaminated by imperfect detection, making direct inference about abundance or occurrence based on observational data infeasible. This article describes a flexible hierarchical modeling framework for estimation and inference about animal abundance and occurrence from survey data that are subject to imperfect detection. Within this framework, we specify models of abundance and detectability of animals at the level of the local populations defined by the sample units. Information at the level of the local population is aggregated by specifying models that describe variation in abundance and detection among sites. We describe likelihood-based and Bayesian methods for estimation and inference under the resulting hierarchical model. We provide two examples of the application of hierarchical models to animal survey data, the first based on removal counts of stream fish and the second based on avian quadrat counts. For both examples, we provide a Bayesian analysis of the models using the software WinBUGS.

  4. A Dynamic Spatio-Temporal Model to Investigate the Effect of Cattle Movements on the Spread of Bluetongue BTV-8 in Belgium

    PubMed Central

    Ensoy, Chellafe; Aerts, Marc; Welby, Sarah; Van der Stede, Yves; Faes, Christel

    2013-01-01

    When Bluetongue Virus Serotype 8 (BTV-8) was first detected in Northern Europe in 2006, several guidelines were immediately put into place with the goal to protect farms and stop the spreading of the disease. This however did not prevent further rapid spread of BTV-8 across Northern Europe. Using information on the 2006 Bluetongue outbreak in cattle farms in Belgium, a spatio-temporal transmission model was formulated. The model quantifies the local transmission of the disease between farms within a municipality, the short-distance transmission between farms across neighbouring municipalities and the transmission as a result of cattle movement. Different municipality-level covariates such as farm density, land composition variables, temperature and precipitation, were assessed as possibly influencing each component of the transmission process. Results showed a significant influence of the different covariates in each model component, particularly the significant effect of temperature and precipitation values in the number of infected farms. The model which allowed us to predict the dynamic spreading of BTV for different movement restriction scenarios, also affirmed the significant impact of cattle movement in the 2006 BTV outbreak pattern. Simulation results further showed the importance of considering the size of restriction zones in the formulation of guidelines for animal infectious diseases. PMID:24244324

  5. A dynamic spatio-temporal model to investigate the effect of cattle movements on the spread of bluetongue BTV-8 in Belgium.

    PubMed

    Ensoy, Chellafe; Aerts, Marc; Welby, Sarah; Van der Stede, Yves; Faes, Christel

    2013-01-01

    When Bluetongue Virus Serotype 8 (BTV-8) was first detected in Northern Europe in 2006, several guidelines were immediately put into place with the goal to protect farms and stop the spreading of the disease. This however did not prevent further rapid spread of BTV-8 across Northern Europe. Using information on the 2006 Bluetongue outbreak in cattle farms in Belgium, a spatio-temporal transmission model was formulated. The model quantifies the local transmission of the disease between farms within a municipality, the short-distance transmission between farms across neighbouring municipalities and the transmission as a result of cattle movement. Different municipality-level covariates such as farm density, land composition variables, temperature and precipitation, were assessed as possibly influencing each component of the transmission process. Results showed a significant influence of the different covariates in each model component, particularly the significant effect of temperature and precipitation values in the number of infected farms. The model which allowed us to predict the dynamic spreading of BTV for different movement restriction scenarios, also affirmed the significant impact of cattle movement in the 2006 BTV outbreak pattern. Simulation results further showed the importance of considering the size of restriction zones in the formulation of guidelines for animal infectious diseases.

  6. Animal models for acute radiation syndrome drug discovery.

    PubMed

    Singh, Vijay K; Newman, Victoria L; Berg, Allison N; MacVittie, Thomas J

    2015-05-01

    Although significant scientific advances have been made over the past six decades in developing safe, nontoxic and effective radiation/medical countermeasures (MCMs) for acute radiation syndrome (ARS), no drug has been approved by the US FDA. The availability of adequate animal models is a prime requisite under the criteria established by the FDA 'animal rule' for the development of novel MCMs for ARS and the discovery of biomarkers for radiation exposure. This article reviews the developments of MCMs to combat ARS, with particular reference to the various animal models (rodents: mouse and rat; canine: beagle; minipigs and nonhuman primates [NHPs]) utilized for the in-depth evaluation. The objective, pathways and challenges of the FDA Animal Efficacy Rule are also discussed. There are a number of well-defined animal models, the mouse, canine and NHP, that are being used for the development of MCMs. Additional animal models, such as the minipig, are under development to further assist in the identification, efficacy testing and approval of MCMs under the FDA Animal Efficacy Rule.

  7. An MR-compatible gyroscope-based arm movement tracking system.

    PubMed

    Shirinbayan, S Iman; Rieger, Jochem W

    2017-03-15

    Functional magnetic resonance imaging is well suited to link neural population activation with movement parameters of complex natural arm movements. However, currently existing MR-compatible arm tracking devices are not constructed to measure arm joint movement parameters of unrestricted movements. Therefore, to date most research focuses on simple arm movements or includes very little knowledge about the actual movement kinematics. We developed a low cost gyroscope-based arm movement tracking system (GAMTS) that features MR-compatibility. The system consists of dual-axis analogue gyroscopes that measure rotations of upper and lower arm joints. After MR artifact reduction, the rotation angles of the individual arm joints are calculated and used to animate a realistic arm model that is implemented in the OpenSim platform. The OpenSim platform can then provide the kinematics of any point on the arm model. In order to demonstrate the capabilities of the system, we first assessed the quality of reconstructed wrist movements in a low-noise environment where typical MR-related problems are absent and finally, we validated the reconstruction in the MR environment. The system provides the kinematics of the whole arm when natural unrestricted arm movements are performed inside the MR-scanner. The GAMTS is reliably capable of reconstructing the kinematics of trajectories and the reconstruction error is small in comparison with the movement induced variation of speed, displacement, and rotation. Moreover, the system can be used to probe brain areas for their correlation with movement kinematics. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Animation Augmented Reality Book Model (AAR Book Model) to Enhance Teamwork

    ERIC Educational Resources Information Center

    Chujitarom, Wannaporn; Piriyasurawong, Pallop

    2017-01-01

    This study aims to synthesize an Animation Augmented Reality Book Model (AAR Book Model) to enhance teamwork and to assess the AAR Book Model to enhance teamwork. Samples are five specialists that consist of one animation specialist, two communication and information technology specialists, and two teaching model design specialists, selected by…

  9. Piperidine, pyridine alkaloid inhibition of fetal movement in a day 40 pregnant goat model

    USDA-ARS?s Scientific Manuscript database

    The inhibition of fetal movement is one mechanism behind the development of multiple congenital contracture-type defects and cleft palate in developing fetuses of humans and animals. In this study, we tested the alkaloids anabasine, lobeline, and myosmine for agonist actions, and sensitivity to alp...

  10. An empirical test of a diffusion model: predicting clouded apollo movements in a novel environment.

    PubMed

    Ovaskainen, Otso; Luoto, Miska; Ikonen, Iiro; Rekola, Hanna; Meyke, Evgeniy; Kuussaari, Mikko

    2008-05-01

    Functional connectivity is a fundamental concept in conservation biology because it sets the level of migration and gene flow among local populations. However, functional connectivity is difficult to measure, largely because it is hard to acquire and analyze movement data from heterogeneous landscapes. Here we apply a Bayesian state-space framework to parameterize a diffusion-based movement model using capture-recapture data on the endangered clouded apollo butterfly. We test whether the model is able to disentangle the inherent movement behavior of the species from landscape structure and sampling artifacts, which is a necessity if the model is to be used to examine how movements depend on landscape structure. We show that this is the case by demonstrating that the model, parameterized with data from a reference landscape, correctly predicts movements in a structurally different landscape. In particular, the model helps to explain why a movement corridor that was constructed as a management measure failed to increase movement among local populations. We illustrate how the parameterized model can be used to derive biologically relevant measures of functional connectivity, thus linking movement data with models of spatial population dynamics.

  11. Assessing habitat connectivity for ground-dwelling animals in an urban environment.

    PubMed

    Braaker, S; Moretti, M; Boesch, R; Ghazoul, J; Obrist, M K; Bontadina, F

    To ensure viable species populations in fragmented landscapes, individuals must be able to move between suitable habitat patches. Despite the increased interest in biodiversity assessment in urban environments, the ecological relevance of habitat connectivity in highly fragmented landscapes remains largely unknown. The first step to understanding the role of habitat connectivity in urban ecology is the challenging task of assessing connectivity in the complex patchwork of contrasting habitats that is found in cities. We developed a data-based framework, minimizing the use of subjective assumptions, to assess habitat connectivity that consists of the following sequential steps: (1) identification of habitat preference based on empirical habitat-use data; (2) derivation of habitat resistance surfaces evaluating various transformation functions; (3) modeling of different connectivity maps with electrical circuit theory (Circuitscape), a method considering all possible pathways across the landscape simultaneously; and (4) identification of the best connectivity map with information-theoretic model selection. We applied this analytical framework to assess habitat connectivity for the European hedgehog Erinaceus europaeus, a model species for ground-dwelling animals, in the city of Zurich, Switzerland, using GPS track points from 40 individuals. The best model revealed spatially explicit connectivity “pinch points,” as well as multiple habitat connections. Cross-validation indicated the general validity of the selected connectivity model. The results show that both habitat connectivity and habitat quality affect the movement of urban hedgehogs (relative importance of the two variables was 19.2% and 80.8%, respectively), and are thus both relevant for predicting urban animal movements. Our study demonstrates that even in the complex habitat patchwork of cities, habitat connectivity plays a major role for ground-dwelling animal movement. Data-based habitat connectivity

  12. Role of Animal Models in Coronary Stenting.

    PubMed

    Iqbal, Javaid; Chamberlain, Janet; Francis, Sheila E; Gunn, Julian

    2016-02-01

    Coronary angioplasty initially employed balloon dilatation only. This technique revolutionized the treatment of coronary artery disease, although outcomes were compromised by acute vessel closure, late constrictive remodeling, and restenosis due to neointimal proliferation. These processes were studied in animal models, which contributed to understanding the biology of endovascular arterial injury. Coronary stents overcome acute recoil, with improvements in the design and metallurgy since then, leading to the development of drug-eluting stents and bioresorbable scaffolds. These devices now undergo computer modeling and benchtop and animal testing before evaluation in clinical trials. Animal models, including rabbit, sheep, dog and pig are available, all with individual benefits and limitations. In smaller mammals, such as mouse and rabbit, the target for stenting is generally the aorta; whereas in larger animals, such as the pig, it is generally the coronary artery. The pig coronary stenting model is a gold-standard for evaluating safety; but insights into biomechanical properties, the biology of stenting, and efficacy in controlling neointimal proliferation can also be gained. Intra-coronary imaging modalities such as intravascular ultrasound and optical coherence tomography allow precise serial evaluation in vivo, and recent developments in genetically modified animal models of atherosclerosis provide realistic test beds for future stents and scaffolds.

  13. Simplified model of mean double step (MDS) in human body movement

    NASA Astrophysics Data System (ADS)

    Dusza, Jacek J.; Wawrzyniak, Zbigniew M.; Mugarra González, C. Fernando

    In this paper we present a simplified and useful model of the human body movement based on the full gait cycle description, called the Mean Double Step (MDS). It enables the parameterization and simplification of the human movement. Furthermore it allows a description of the gait cycle by providing standardized estimators to transform the gait cycle into a periodical movement process. Moreover the method of simplifying the MDS model and its compression are demonstrated. The simplification is achieved by reducing the number of bars of the spectrum and I or by reducing the number of samples describing the MDS both in terms of reducing their computational burden and their resources for the data storage. Our MDS model, which is applicable to the gait cycle method for examining patients, is non-invasive and provides the additional advantage of featuring a functional characterization of the relative or absolute movement of any part of the body.

  14. Simulation of between-farm transmission of porcine reproductive and respiratory syndrome virus in Ontario, Canada using the North American Animal Disease Spread Model.

    PubMed

    Thakur, Krishna K; Revie, Crawford W; Hurnik, Daniel; Poljak, Zvonimir; Sanchez, Javier

    2015-03-01

    Porcine reproductive and respiratory syndrome (PRRS), a viral disease of swine, has major economic impacts on the swine industry. The North American Animal Disease Spread Model (NAADSM) is a spatial, stochastic, farm level state-transition modeling framework originally developed to simulate highly contagious and foreign livestock diseases. The objectives of this study were to develop a model to simulate between-farm spread of a homologous strain of PRRS virus in Ontario swine farms via direct (animal movement) and indirect (sharing of trucks between farms) contacts using the NAADSM and to compare the patterns and extent of outbreak under different simulated conditions. A total of 2552 swine farms in Ontario province were allocated to each census division of Ontario and geo-locations of the farms were randomly generated within the agriculture land of each Census Division. Contact rates among different production types were obtained using pig movement information from four regions in Canada. A total of 24 scenarios were developed involving various direct (movement of infected animals) and indirect (pig transportation trucks) contact parameters in combination with alternating the production type of the farm in which the infection was seeded. Outbreaks were simulated for one year with 1000 replications. The median number of farms infected, proportion of farms with multiple outbreaks and time to reach the peak epidemic were used to compare the size, progression and extent of outbreaks. Scenarios involving spread only by direct contact between farms resulted in outbreaks where the median percentage of infected farms ranged from 31.5 to 37% of all farms. In scenarios with both direct and indirect contact, the median percentage of infected farms increased to a range from 41.6 to 48.6%. Furthermore, scenarios with both direct and indirect contact resulted in a 44% increase in median epidemic size when compared to the direct contact scenarios. Incorporation of both animal

  15. Movement impairment: Focus on the brain.

    PubMed

    Adami, Raffaella; Bottai, Daniele

    2016-04-01

    The saying "mens sana in corpore sano" has a particular resonance these days because, for the majority who have a very sedentary occupation, the everyday rhythms of life do not compel us to do much physical exercise. Recently published data indicate that exercise can counteract the effects of neurological diseases such as Alzheimer's disease and have prompted research on the beneficial effects of movement on the brain and brain neurogenesis. This might lead us to hypothesize that the absence or reduction of movements, especially those with antigravity effects, could induce a deterioration of the brain. This Review discusses current knowledge of the relationship between neurogenic capacity and the lack of motor activity in human and animal models. © 2016 Wiley Periodicals, Inc.

  16. Sensor-based animal tracking

    NASA Astrophysics Data System (ADS)

    Hunter, Andrew

    The advent of Global Positioning System (GPS) technologies has provided wildlife researchers with new insights into the movement and habitat utilization patterns of wildlife species by being able to provide vast quantities of detailed location data. However, current wildlife tracking techniques have numerous limitations, as GPS locations can be biased to an unknown extent because animals move through habitats that are often denied GPS signals. This can result in some habitat types being under sampled or not sampled at all. Additionally, researchers using GPS tracking systems cannot understand what behaviour an animal is exhibiting at each GPS position without either relying on extensive field data or statistical techniques that may infer behaviour. Overall these issues, and others, limit the knowledge that can be derived from the data currently being collected by GPS collars alone. To address these limitations, a dead reckoning solution (called the NavAid) has been developed to augment GPS tracking collars, which enables both the acquisition of continuous movement trajectories for animals under study, and the collection of digital images on a user-defined schedule along travel routes. Analysis of an animal's velocity allows one to identify different types of movement behaviours that can be associated with foraging, searching for food, and locomotion between patches. In addition, the ability to capture continuous paths allows researchers to identify habitat that is important to a species, and habitat that is not---something that is not possible when relying solely on GPS. This new system weighs approximately 220 g and can be deployed on most conventional collar systems for a wide range of species. This thesis presents the research and development of this new system over the past four years, along with preliminary findings from field work carried out on grizzly bears (Ursus arctos) in the foothills of the Canadian Rocky Mountains. Analysis of tracking data suggests

  17. Systematic Reviews of Animal Models: Methodology versus Epistemology

    PubMed Central

    Greek, Ray; Menache, Andre

    2013-01-01

    Systematic reviews are currently favored methods of evaluating research in order to reach conclusions regarding medical practice. The need for such reviews is necessitated by the fact that no research is perfect and experts are prone to bias. By combining many studies that fulfill specific criteria, one hopes that the strengths can be multiplied and thus reliable conclusions attained. Potential flaws in this process include the assumptions that underlie the research under examination. If the assumptions, or axioms, upon which the research studies are based, are untenable either scientifically or logically, then the results must be highly suspect regardless of the otherwise high quality of the studies or the systematic reviews. We outline recent criticisms of animal-based research, namely that animal models are failing to predict human responses. It is this failure that is purportedly being corrected via systematic reviews. We then examine the assumption that animal models can predict human outcomes to perturbations such as disease or drugs, even under the best of circumstances. We examine the use of animal models in light of empirical evidence comparing human outcomes to those from animal models, complexity theory, and evolutionary biology. We conclude that even if legitimate criticisms of animal models were addressed, through standardization of protocols and systematic reviews, the animal model would still fail as a predictive modality for human response to drugs and disease. Therefore, systematic reviews and meta-analyses of animal-based research are poor tools for attempting to reach conclusions regarding human interventions. PMID:23372426

  18. Modeling potential movements of the emerald ash borer: the model framework

    Treesearch

    Louis R. Iverson; Anantha Prasad; Jonathan Bossenbroek; Davis Sydnor; Mark W. Schwartz

    2010-01-01

    The emerald ash borer (EAB, Agrilus planipennis Fairmaire) is threatening to decimate native ashes (Fraxinus spp.) across North America and, so far, has devastated ash populations across sections of Michigan, Ohio, Indiana, and Ontario. We are attempting to develop a computer model that will predict EAB future movement by adapting a model developed...

  19. Animal rights and animal experimentation. Implications for physicians.

    PubMed Central

    Gelpi, A. P.

    1991-01-01

    Practicing physicians are just becoming aware of the animal rights movement, which during the 1980s spawned numerous acts of violence against research facilities throughout the United States. The animal rightists are challenging physicians to show moral justification for the human exploitation of nature and the world of subhuman species. They have aroused public interest in animal welfare, sparked protective legislation for experimental animals, and indirectly encouraged the creation of committees to oversee the conduct of animal experimentation and the conditions of animal confinement. This controversy has necessitated a closer look at the questions of animal experimentation and animal rights against the backdrop of human experimentation and human rights. Physicians and specialists in animal care seek to alleviate suffering and anxiety, and, as moderates, they may be able to bring both sides of the animal rights controversy together in a spirit of mutual tolerance and in the common cause of promoting both human and animal welfare. PMID:1949772

  20. Large animal models for vaccine development and testing.

    PubMed

    Gerdts, Volker; Wilson, Heather L; Meurens, Francois; van Drunen Littel-van den Hurk, Sylvia; Wilson, Don; Walker, Stewart; Wheler, Colette; Townsend, Hugh; Potter, Andrew A

    2015-01-01

    The development of human vaccines continues to rely on the use of animals for research. Regulatory authorities require novel vaccine candidates to undergo preclinical assessment in animal models before being permitted to enter the clinical phase in human subjects. Substantial progress has been made in recent years in reducing and replacing the number of animals used for preclinical vaccine research through the use of bioinformatics and computational biology to design new vaccine candidates. However, the ultimate goal of a new vaccine is to instruct the immune system to elicit an effective immune response against the pathogen of interest, and no alternatives to live animal use currently exist for evaluation of this response. Studies identifying the mechanisms of immune protection; determining the optimal route and formulation of vaccines; establishing the duration and onset of immunity, as well as the safety and efficacy of new vaccines, must be performed in a living system. Importantly, no single animal model provides all the information required for advancing a new vaccine through the preclinical stage, and research over the last two decades has highlighted that large animals more accurately predict vaccine outcome in humans than do other models. Here we review the advantages and disadvantages of large animal models for human vaccine development and demonstrate that much of the success in bringing a new vaccine to market depends on choosing the most appropriate animal model for preclinical testing. © The Author 2015. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  1. Artificial pigs in space: using artificial intelligence and artificial life techniques to design animal housing.

    PubMed

    Stricklin, W R; de Bourcier, P; Zhou, J Z; Gonyou, H W

    1998-10-01

    Computer simulations have been used by us since the early 1970s to gain an understanding of the spacing and movement patterns of confined animals. The work has progressed from the early stages, in which we used randomly positioned points, to current investigations of animats (computer-simulated animals), which show low levels of learning via artificial neural networks. We have determined that 1) pens of equal floor area but of different shape result in different spatial and movement patterns for randomly positioned and moving animats; 2) when group size increases under constant density, freedom of movement approaches an asymptote at approximately six animats; 3) matching the number of animats with the number of corners results in optimal freedom of movement for small groups of animats; and 4) perimeter positioning occurs in groups of animats that maximize their distance to first- and second-nearest neighbors. Recently, we developed animats that move, compete for social dominance, and are motivated to obtain resources (food, resting sites, etc.). We are currently developing an animat that learns its behavior from the spatial and movement data collected on live pigs. The animat model is then used to pretest pen designs, followed by new pig spatial data fed into the animat model, resulting in a new pen design to be tested, and the steps are repeated. We believe that methodologies from artificial-life and artificial intelligence can contribute to the understanding of basic animal behavior principles, as well as to the solving of problems in production agriculture in areas such as animal housing design.

  2. Elements of episodic-like memory in animal models.

    PubMed

    Crystal, Jonathon D

    2009-03-01

    Representations of unique events from one's past constitute the content of episodic memories. A number of studies with non-human animals have revealed that animals remember specific episodes from their past (referred to as episodic-like memory). The development of animal models of memory holds enormous potential for gaining insight into the biological bases of human memory. Specifically, given the extensive knowledge of the rodent brain, the development of rodent models of episodic memory would open new opportunities to explore the neuroanatomical, neurochemical, neurophysiological, and molecular mechanisms of memory. Development of such animal models holds enormous potential for studying functional changes in episodic memory in animal models of Alzheimer's disease, amnesia, and other human memory pathologies. This article reviews several approaches that have been used to assess episodic-like memory in animals. The approaches reviewed include the discrimination of what, where, and when in a radial arm maze, dissociation of recollection and familiarity, object recognition, binding, unexpected questions, and anticipation of a reproductive state. The diversity of approaches may promote the development of converging lines of evidence on the difficult problem of assessing episodic-like memory in animals.

  3. Chimeric animal models in human stem cell biology.

    PubMed

    Glover, Joel C; Boulland, Jean-Luc; Halasi, Gabor; Kasumacic, Nedim

    2009-01-01

    The clinical use of stem cells for regenerative medicine is critically dependent on preclinical studies in animal models. In this review we examine some of the key issues and challenges in the use of animal models to study human stem cell biology-experimental standardization, body size, immunological barriers, cell survival factors, fusion of host and donor cells, and in vivo imaging and tracking. We focus particular attention on the various imaging modalities that can be used to track cells in living animals, comparing their strengths and weaknesses and describing technical developments that are likely to lead to new opportunities for the dynamic assessment of stem cell behavior in vivo. We then provide an overview of some of the most commonly used animal models, their advantages and disadvantages, and examples of their use for xenotypic transplantation of human stem cells, with separate reviews of models involving rodents, ungulates, nonhuman primates, and the chicken embryo. As the use of human somatic, embryonic, and induced pluripotent stem cells increases, so too will the range of applications for these animal models. It is likely that increasingly sophisticated uses of human/animal chimeric models will be developed through advances in genetic manipulation, cell delivery, and in vivo imaging.

  4. Effect of fluoxetine on induced tooth movement in rats.

    PubMed

    Franzon Frigotto, Giovana Carla; Miranda de Araujo, Cristiano; Guariza Filho, Odilon; Tanaka, Orlando Motohiro; Batista Rodrigues Johann, Aline Cristina; Camargoa, Elisa Souza

    2015-09-01

    Fluoxetine is a widely used antidepressant. Its various effects on bone mineral density are well described. The aim of this study was to evaluate the effect of fluoxetine on induced tooth movement. Seventy-two Wistar rats were divided into 3 groups: M (n = 24; 0.9% saline solution and induced tooth movement), FM (n = 24; fluoxetine, 10 mg/kg, and induced tooth movement), and F (n = 24; fluoxetine, 10 mg/kg only). After 30 days of daily saline solution or fluoxetine administration, an orthodontic appliance (30 cN) was used to displace the first molar mesially in groups M and FM. The animals were killed 3, 7, and 14 days after placement of the orthodontic appliances. The animals in group F did not receive induced tooth movement but were killed at the same times. We evaluated tooth movement rates, collagen neoformation rates by polarization microscopy, numbers of osteoclast by tartrate-resistant acid phosphatase, and trabecular bone modeling by microcomputed tomography of the femur. The tooth movement rates were similar in groups M and FM at all studied time points (P >0.05). The rate of newly formed collagen had a reverse pattern in groups M and FM, but the difference was not statistically significant (P >0.05). There were significantly more osteoclasts in group FM than in group F on day 3 (P <0.01). The trabecular spacing was significantly larger in group F compared with group M on day 14 (P <0.05). Fluoxetine did not interfere with induced tooth movement or trabecular bone in rats. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  5. Features of microscopic pedestrian movement in a panic situation based on cellular automata model

    NASA Astrophysics Data System (ADS)

    Ibrahim, Najihah; Hassan, Fadratul Hafinaz

    2017-10-01

    Pedestrian movement is the one of the subset for the crowd management under simulation objective. During panic situation, pedestrian usually will create a microscopic movement that lead towards the self-organization. During self-organizing, the behavioral and physical factors had caused the mass effect on the pedestrian movement. The basic CA model will create a movement path for each pedestrian over a time step. However, due to the factors immerge, the CA model needs some enhancement that will establish a real simulation state. Hence, this concept paper will discuss on the enhanced features of CA model for microscopic pedestrian movement during panic situation for a better pedestrian simulation.

  6. Movement is the glue connecting home ranges and habitat selection.

    PubMed

    Van Moorter, Bram; Rolandsen, Christer M; Basille, Mathieu; Gaillard, Jean-Michel

    2016-01-01

    Animal space use has been studied by focusing either on geographic (e.g. home ranges, species' distribution) or on environmental (e.g. habitat use and selection) space. However, all patterns of space use emerge from individual movements, which are the primary means by which animals change their environment. Individuals increase their use of a given area by adjusting two key movement components: the duration of their visit and/or the frequency of revisits. Thus, in spatially heterogeneous environments, animals exploit known, high-quality resource areas by increasing their residence time (RT) in and/or decreasing their time to return (TtoR) to these areas. We expected that spatial variation in these two movement properties should lead to observed patterns of space use in both geographic and environmental spaces. We derived a set of nine predictions linking spatial distribution of movement properties to emerging space-use patterns. We predicted that, at a given scale, high variation in RT and TtoR among habitats leads to strong habitat selection and that long RT and short TtoR result in a small home range size. We tested these predictions using moose (Alces alces) GPS tracking data. We first modelled the relationship between landscape characteristics and movement properties. Then, we investigated how the spatial distribution of predicted movement properties (i.e. spatial autocorrelation, mean, and variance of RT and TtoR) influences home range size and hierarchical habitat selection. In landscapes with high spatial autocorrelation of RT and TtoR, a high variation in both RT and TtoR occurred in home ranges. As expected, home range location was highly selective in such landscapes (i.e. second-order habitat selection); RT was higher and TtoR lower within the selected home range than outside, and moose home ranges were small. Within home ranges, a higher variation in both RT and TtoR was associated with higher selectivity among habitat types (i.e. third-order habitat

  7. Microbicide safety/efficacy studies in animals: macaques and small animal models.

    PubMed

    Veazey, Ronald S

    2008-09-01

    A number of microbicide candidates have failed to prevent HIV transmission in human clinical trials, and there is uncertainty as to how many additional trials can be supported by the field. Regardless, there are far too many microbicide candidates in development, and a logical and consistent method for screening and selecting candidates for human clinical trials is desperately needed. The unique host and cell specificity of HIV, however, provides challenges for microbicide safety and efficacy screening, that can only be addressed by rigorous testing in relevant laboratory animal models. A number of laboratory animal model systems ranging from rodents to nonhuman primates, and single versus multiple dose challenges have recently been developed to test microbicide candidates. These models have shed light on both the safety and efficacy of candidate microbicides as well as the early mechanisms involved in transmission. This article summarizes the major advantages and disadvantages of the relevant animal models for microbicide safety and efficacy testing. Currently, nonhuman primates are the only relevant and effective laboratory model for screening microbicide candidates. Given the consistent failures of prior strategies, it is now clear that rigorous safety and efficacy testing in nonhuman primates should be a prerequisite for advancing additional microbicide candidates to human clinical trials.

  8. Microbicide Safety/Efficacy studies in animals -macaques and small animal models

    PubMed Central

    Veazey, Ronald S.

    2009-01-01

    Purpose of review A number of microbicide candidates have failed to prevent HIV transmission in human clinical trials, and there is uncertainty as to how many additional trials can be supported by the field. Regardless, there are far too many microbicide candidates in development, and a logical and consistent method for screening and selecting candidates for human clinical trials is desperately needed. However, the unique host and cell specificity of HIV provides challenges for microbicide safety and efficacy screening, that can only be addressed by rigorous testing in relevant laboratory animal models. Recent findings A number of laboratory animal model systems ranging from rodents to nonhuman primates, and single versus multiple dose challenges have recently been developed to test microbicide candidates. These models have shed light on both the safety and efficacy of candidate microbicides as well as the early mechanisms involved in transmission. This article summarizes the major advantages and disadvantages of the relevant animal models for microbicide safety and efficacy testing. Summary Currently, nonhuman primates are the only relevant and effective laboratory model for screening microbicide candidates. Given the consistent failures of prior strategies, it is now clear that rigorous safety and efficacy testing in nonhuman primates should be a pre-requisite for advancing additional microbicide candidates to human clinical trials. PMID:19373023

  9. Animal Models of Zika Virus.

    PubMed

    Bradley, Michael P; Nagamine, Claude M

    2017-06-01

    Zika virus has garnered great attention over the last several years, as outbreaks of the disease have emerged throughout the Western Hemisphere. Until quite recently Zika virus was considered a fairly benign virus, with limited clinical severity in both people and animals. The size and scope of the outbreak in the Western Hemisphere has allowed for the identification of severe clinical disease that is associated with Zika virus infection, most notably microcephaly among newborns, and an association with Guillian-Barré syndrome in adults. This recent association with severe clinical disease, of which further analysis strongly suggested causation by Zika virus, has resulted in a massive increase in the amount of both basic and applied research of this virus. Both small and large animal models are being used to uncover the pathogenesis of this emerging disease and to develop vaccine and therapeutic strategies. Here we review the animal-model-based Zika virus research that has been performed to date.

  10. 9 CFR 72.2 - Restrictions on movement of cattle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Restrictions on movement of cattle. 72.2 Section 72.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BOVINE BABESIOSIS...

  11. Animal models of asthma: utility and limitations.

    PubMed

    Aun, Marcelo Vivolo; Bonamichi-Santos, Rafael; Arantes-Costa, Fernanda Magalhães; Kalil, Jorge; Giavina-Bianchi, Pedro

    2017-01-01

    Clinical studies in asthma are not able to clear up all aspects of disease pathophysiology. Animal models have been developed to better understand these mechanisms and to evaluate both safety and efficacy of therapies before starting clinical trials. Several species of animals have been used in experimental models of asthma, such as Drosophila , rats, guinea pigs, cats, dogs, pigs, primates and equines. However, the most common species studied in the last two decades is mice, particularly BALB/c. Animal models of asthma try to mimic the pathophysiology of human disease. They classically include two phases: sensitization and challenge. Sensitization is traditionally performed by intraperitoneal and subcutaneous routes, but intranasal instillation of allergens has been increasingly used because human asthma is induced by inhalation of allergens. Challenges with allergens are performed through aerosol, intranasal or intratracheal instillation. However, few studies have compared different routes of sensitization and challenge. The causative allergen is another important issue in developing a good animal model. Despite being more traditional and leading to intense inflammation, ovalbumin has been replaced by aeroallergens, such as house dust mites, to use the allergens that cause human disease. Finally, researchers should define outcomes to be evaluated, such as serum-specific antibodies, airway hyperresponsiveness, inflammation and remodeling. The present review analyzes the animal models of asthma, assessing differences between species, allergens and routes of allergen administration.

  12. Animal Models for Salmonellosis: Applications in Vaccine Research

    PubMed Central

    Higginson, Ellen E.; Simon, Raphael

    2016-01-01

    Salmonellosis remains an important cause of human disease worldwide. While there are several licensed vaccines for Salmonella enterica serovar Typhi, these vaccines are generally ineffective against other Salmonella serovars. Vaccines that target paratyphoid and nontyphoidal Salmonella serovars are very much in need. Preclinical evaluation of candidate vaccines is highly dependent on the availability of appropriate scientific tools, particularly animal models. Many different animal models exist for various Salmonella serovars, from whole-animal models to smaller models, such as those recently established in insects. Here, we discuss various mouse, rat, rabbit, calf, primate, and insect models for Salmonella infection, all of which have their place in research. However, choosing the right model is imperative in selecting the best vaccine candidates for further clinical testing. In this minireview, we summarize the various animal models that are used to assess salmonellosis, highlight some of the advantages and disadvantages of each, and discuss their value in vaccine development. PMID:27413068

  13. An indexing and price movement model for managing pension funds.

    PubMed

    Freeman, H R

    1994-10-01

    A model for the investment of pension funds has been created that combines passive and active portfolio management strategies. The model uses a passive index fund to reduce the amount spent in transaction costs. It applies a percentage band that identifies the portion of the portfolio that should be committed to equity investments at various stages of the market movement cycle. Finally, it uses price movement trigger points to dictate when pension funds should be moved into and withdrawn from stock market investments.

  14. Dynamic model of the octopus arm. I. Biomechanics of the octopus reaching movement.

    PubMed

    Yekutieli, Yoram; Sagiv-Zohar, Roni; Aharonov, Ranit; Engel, Yaakov; Hochner, Binyamin; Flash, Tamar

    2005-08-01

    The octopus arm requires special motor control schemes because it consists almost entirely of muscles and lacks a rigid skeletal support. Here we present a 2D dynamic model of the octopus arm to explore possible strategies of movement control in this muscular hydrostat. The arm is modeled as a multisegment structure, each segment containing longitudinal and transverse muscles and maintaining a constant volume, a prominent feature of muscular hydrostats. The input to the model is the degree of activation of each of its muscles. The model includes the external forces of gravity, buoyancy, and water drag forces (experimentally estimated here). It also includes the internal forces generated by the arm muscles and the forces responsible for maintaining a constant volume. Using this dynamic model to investigate the octopus reaching movement and to explore the mechanisms of bend propagation that characterize this movement, we found the following. 1) A simple command producing a wave of muscle activation moving at a constant velocity is sufficient to replicate the natural reaching movements with similar kinematic features. 2) The biomechanical mechanism that produces the reaching movement is a stiffening wave of muscle contraction that pushes a bend forward along the arm. 3) The perpendicular drag coefficient for an octopus arm is nearly 50 times larger than the tangential drag coefficient. During a reaching movement, only a small portion of the arm is oriented perpendicular to the direction of movement, thus minimizing the drag force.

  15. The Therapeutic Potential of Cannabinoids for Movement Disorders

    PubMed Central

    Kluger, Benzi; Triolo, Piera; Jones, Wallace; Jankovic, Joseph

    2014-01-01

    Background There is growing interest in the therapeutic potential of marijuana (cannabis) and cannabinoid-based chemicals within the medical community and particularly for neurologic conditions. This interest is driven both by changes in the legal status of cannabis in many areas and increasing research into the roles of endocannabinoids within the central nervous system and their potential as symptomatic and/or neuroprotective therapies. We review basic science, preclinical and clinical studies on the therapeutic potential of cannabinoids specifically as it relates to movement disorders. Results The pharmacology of cannabis is complex with over 60 neuroactive chemicals identified to date. The endocannabinoid system modulates neurotransmission involved in motor function, particularly within the basal ganglia. Preclinical research in animal models of several movement disorders have shown variable evidence for symptomatic benefits but more consistently suggest potential neuroprotective effects in several animal models of Parkinson’s (PD) and Huntington’s disease (HD). Clinical observations and clinical trials of cannabinoid-based therapies suggests a possible benefit of cannabinoids for tics and probably no benefit for tremor in multiple sclerosis or dyskinesias or motor symptoms in PD. Data are insufficient to draw conclusions regarding HD, dystonia or ataxia and nonexistent for myoclonus or restless legs syndrome. Conclusions Despite the widespread publicity about the medical benefits of cannabinoids, further preclinical and clinical research is needed to better characterize the pharmacological, physiological and therapeutic effects of this class of drugs in movement disorders. PMID:25649017

  16. [Thoughts on the complex relationship between medicine and animals: a death prayer for a loyal cat].

    PubMed

    Cabello C, Felipe

    2013-11-01

    From its basis in the writings of the philosopher Peter Singer and the bioethical shortcomings of animal experimentation and animal husbandry, the animal rights movement has evolved into an important societal movement critical of animal experimentation in biomedical research. A lack of dialogue and transparency, an absence of understanding and an unreasonable radicalization of different positions regarding animal experimentation has frequently resulted in an adversarial relationship between some members of the scientific community and societal groups aggressively protecting animal rights. In response to this problem, both the bioethical regulations pertaining to biomedical experimentation with animals and the powers of animal care committees (IACUCs) have been strengthened. Careful analysis of the relevance of animal models to human conditions, replacement of these models with non-animal models when possible, adequate re-examination of existing knowledge before undertaking new experimental projects involving animals, and the improvement of methods to avoid animal stress and pain have further strengthened the bioethical basis of animal experimentation. To improve the ethical integrity of research conducted with animals, it is also necessary to increase the editorial scrutiny of the bioethical standards of potentially publishable research utilizing animals. Of note is also the recent use of animals in alternative animal associated therapies (AAT) to ameliorate several medical conditions. Education of the biomedical community, including students and professionals, and of societal groups concerned about this issue as well as directness and continuous dialogue among all the stakeholders are essential to insure the wellbeing of animals and the ethical integrity of biomedical research.

  17. Modeling Lithium Movement over Multiple Cycles in a Lithium-Metal Battery

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

    Ferrese, A; Newman, J

    This paper builds on the work by Ferrese et al. [J. Electrochem., 159, A1615 (2012)], where a model of a lithium-metal battery with a LiyCoO2 positive electrode was created in order to predict the movement of lithium in the negative electrode along the negative electrode/separator interface during cell cycling. In this paper, the model is expanded to study the movement of lithium along the lithium-metal anode over multiple cycles. From this model, it is found that when a low percentage of lithium at the negative electrode is utilized, the movement of lithium along the negative electrode/separator interface reaches a quasimore » steady state after multiple cycles. This steady state is affected by the slope of the open-circuit-potential function in the positive electrode, the rate of charge and discharge, the depth of discharge, and the length of the rest periods. However, when a high percent of the lithium at the negative electrode is utilized during cycling, the movement does not reach a steady state and pinching can occur, where the lithium nearest the negative tab becomes progressively thinner after cycling. This is another nonlinearity that leads to a progression of the movement of lithium over multiple cycles. (C) 2014 The Electrochemical Society.« less

  18. Suspended animation in C. elegans requires the spindle checkpoint.

    PubMed

    Nystul, Todd G; Goldmark, Jesse P; Padilla, Pamela A; Roth, Mark B

    2003-11-07

    In response to environmental signals such as anoxia, many organisms enter a state of suspended animation, an extreme form of quiescence in which microscopically visible movement ceases. We have identified a gene, san-1, that is required for suspended animation in Caenorhabditis elegans embryos. We show that san-1 functions as a spindle checkpoint component in C. elegans. During anoxia-induced suspended animation, embryos lacking functional SAN-1 or a second spindle checkpoint component, MDF-2, failed to arrest the cell cycle, exhibited chromosome missegregation, and showed reduced viability. These data provide a model for how a dynamic biological process is arrested in suspended animation.

  19. A new physical model with multilayer architecture for facial expression animation using dynamic adaptive mesh.

    PubMed

    Zhang, Yu; Prakash, Edmond C; Sung, Eric

    2004-01-01

    This paper presents a new physically-based 3D facial model based on anatomical knowledge which provides high fidelity for facial expression animation while optimizing the computation. Our facial model has a multilayer biomechanical structure, incorporating a physically-based approximation to facial skin tissue, a set of anatomically-motivated facial muscle actuators, and underlying skull structure. In contrast to existing mass-spring-damper (MSD) facial models, our dynamic skin model uses the nonlinear springs to directly simulate the nonlinear visco-elastic behavior of soft tissue and a new kind of edge repulsion spring is developed to prevent collapse of the skin model. Different types of muscle models have been developed to simulate distribution of the muscle force applied on the skin due to muscle contraction. The presence of the skull advantageously constrain the skin movements, resulting in more accurate facial deformation and also guides the interactive placement of facial muscles. The governing dynamics are computed using a local semi-implicit ODE solver. In the dynamic simulation, an adaptive refinement automatically adapts the local resolution at which potential inaccuracies are detected depending on local deformation. The method, in effect, ensures the required speedup by concentrating computational time only where needed while ensuring realistic behavior within a predefined error threshold. This mechanism allows more pleasing animation results to be produced at a reduced computational cost.

  20. Establishing a laboratory animal model from a transgenic animal: RasH2 mice as a model for carcinogenicity studies in regulatory science.

    PubMed

    Urano, K; Tamaoki, N; Nomura, T

    2012-01-01

    Transgenic animal models have been used in small numbers in gene function studies in vivo for a period of time, but more recently, the use of a single transgenic animal model has been approved as a second species, 6-month alternative (to the routine 2-year, 2-animal model) used in short-term carcinogenicity studies for generating regulatory application data of new drugs. This article addresses many of the issues associated with the creation and use of one of these transgenic models, the rasH2 mouse, for regulatory science. The discussion includes strategies for mass producing mice with the same stable phenotype, including constructing the transgene, choosing a founder mouse, and controlling both the transgene and background genes; strategies for developing the model for regulatory science, including measurements of carcinogen susceptibility, stability of a large-scale production system, and monitoring for uniform carcinogenicity responses; and finally, efficient use of the transgenic animal model on study. Approximately 20% of mouse carcinogenicity studies for new drug applications in the United States currently use transgenic models, typically the rasH2 mouse. The rasH2 mouse could contribute to animal welfare by reducing the numbers of animals used as well as reducing the cost of carcinogenicity studies. A better understanding of the advantages and disadvantages of the transgenic rasH2 mouse will result in greater and more efficient use of this animal model in the future.

  1. Animal Models of Hemophilia and Related Bleeding Disorders

    PubMed Central

    Lozier, Jay N.; Nichols, Timothy C.

    2013-01-01

    Animal models of hemophilia and related diseases are important for development of novel treatments and to understand the pathophysiology of bleeding disorders in humans. Testing in animals with the equivalent human disorder provides informed estimates of doses and measures of efficacy, which aids in design of human trials. Many models of hemophilia A, hemophilia B, and von Willebrand disease have been developed from animals with spontaneous mutations (hemophilia A dogs, rats, sheep; hemophilia B dogs; and von Willebrand disease pigs and dogs), or by targeted gene disruption in mice to create hemophilia A, B, or VWD models. Animal models have been used to generate new insights into the pathophysiology of each bleeding disorder and also to perform pre-clinical assessments of standard protein replacement therapies as well as novel gene transfer technology. Both the differences between species and differences in underlying causative mutations must be considered in choosing the best animal for a specific scientific study PMID:23956467

  2. An inverse dynamics approach to face animation.

    PubMed

    Pitermann, M; Munhall, K G

    2001-09-01

    Muscle-based models of the human face produce high quality animation but rely on recorded muscle activity signals or synthetic muscle signals that are often derived by trial and error. This paper presents a dynamic inversion of a muscle-based model (Lucero and Munhall, 1999) that permits the animation to be created from kinematic recordings of facial movements. Using a nonlinear optimizer (Powell's algorithm), the inversion produces a muscle activity set for seven muscles in the lower face that minimize the root mean square error between kinematic data recorded with OPTOTRAK and the corresponding nodes of the modeled facial mesh. This inverted muscle activity is then used to animate the facial model. In three tests of the inversion, strong correlations were observed for kinematics produced from synthetic muscle activity, for OPTOTRAK kinematics recorded from a talker for whom the facial model is morphologically adapted and finally for another talker with the model morphology adapted to a different individual. The correspondence between the animation kinematics and the three-dimensional OPTOTRAK data are very good and the animation is of high quality. Because the kinematic to electromyography (EMG) inversion is ill posed, there is no relation between the actual EMG and the inverted EMG. The overall redundancy of the motor system means that many different EMG patterns can produce the same kinematic output.

  3. Animal Models of Suicide Trait-Related Behaviors

    PubMed Central

    Malkesman, Oz; Pine, Daniel; Tragon, Tyson; Austin, Daniel R.; Henter, Ioline D.; Chen, Guang; Manji, Husseini K.

    2009-01-01

    Although antidepressants are at least moderately effective in treating major depressive disorder (MDD), concerns have arisen that selective serotonin reuptake inhibitors (SSRIs) are associated with suicidal thinking and behavior, especially in children, adolescents, and young adults. Virtually no experimental research in model systems has considered the mechanisms by which SSRIs may be associated with this potential side effect in some susceptible individuals. Suicide is a complex behavior that is, at best, complicated to study in humans and impossible to fully reproduce in an animal model. However, by investigating traits that show strong cross-species parallels as well as associations with suicide in humans, animal models may elucidate the mechanisms by which SSRIs are associated with suicidal thinking and behavior in the young. Traits linked with suicide in humans that can be successfully modeled in rodents include aggression, impulsivity, irritability, and hopelessness/helplessness. Differences in animal response to particular paradigms and to SSRIs across the lifespan are also discussed. Modeling these relevant traits in animals can help clarify the impact of SSRIs on these traits, suggesting avenues for reducing suicide risk in this vulnerable population. PMID:19269045

  4. Continuous movement decoding using a target-dependent model with EMG inputs.

    PubMed

    Sachs, Nicholas A; Corbett, Elaine A; Miller, Lee E; Perreault, Eric J

    2011-01-01

    Trajectory-based models that incorporate target position information have been shown to accurately decode reaching movements from bio-control signals, such as muscle (EMG) and cortical activity (neural spikes). One major hurdle in implementing such models for neuroprosthetic control is that they are inherently designed to decode single reaches from a position of origin to a specific target. Gaze direction can be used to identify appropriate targets, however information regarding movement intent is needed to determine when a reach is meant to begin and when it has been completed. We used linear discriminant analysis to classify limb states into movement classes based on recorded EMG from a sparse set of shoulder muscles. We then used the detected state transitions to update target information in a mixture of Kalman filters that incorporated target position explicitly in the state, and used EMG activity to decode arm movements. Updating the target position initiated movement along new trajectories, allowing a sequence of appropriately timed single reaches to be decoded in series and enabling highly accurate continuous control.

  5. Animal models for percutaneous-device-related infections: a review.

    PubMed

    Shao, Jinlong; Kolwijck, Eva; Jansen, John A; Yang, Fang; Walboomers, X Frank

    2017-06-01

    This review focuses on the construction of animal models for percutaneous-device-related infections, and specifically the role of inoculation of bacteria in such models. Infections around percutaneous devices, such as catheters, dental implants and limb prostheses, are a recurrent and persistent clinical problem. To promote the research on this clinical problem, the establishment of a reliable and validated animal model would be of keen interest. In this review, literature related to percutaneous devices was evaluated, and particular attention was paid to studies involving the use of bacteria. The design of percutaneous devices, susceptibility of various animal species, bacterial strains, amounts of bacteria, method of inoculation and methods for subsequent evaluation of the infection are discussed in detail. Given that an ideal animal model for study of percutaneous-device-related infection is still not existent, this article presents the basis for the construction of such a standardized animal model for percutaneous-device-related infection studies. The inoculation of bacteria is critical to obtain an animal model for standardized studies for percutaneous-device-related infections. Copyright © 2017. Published by Elsevier B.V.

  6. Sex differences in animal models of psychiatric disorders

    PubMed Central

    Kokras, N; Dalla, C

    2014-01-01

    Psychiatric disorders are characterized by sex differences in their prevalence, symptomatology and treatment response. Animal models have been widely employed for the investigation of the neurobiology of such disorders and the discovery of new treatments. However, mostly male animals have been used in preclinical pharmacological studies. In this review, we highlight the need for the inclusion of both male and female animals in experimental studies aiming at gender-oriented prevention, diagnosis and treatment of psychiatric disorders. We present behavioural findings on sex differences from animal models of depression, anxiety, post-traumatic stress disorder, substance-related disorders, obsessive–compulsive disorder, schizophrenia, bipolar disorder and autism. Moreover, when available, we include studies conducted across different stages of the oestrous cycle. By inspection of the relevant literature, it is obvious that robust sex differences exist in models of all psychiatric disorders. However, many times results are conflicting, and no clear conclusion regarding the direction of sex differences and the effect of the oestrous cycle is drawn. Moreover, there is a lack of considerable amount of studies using psychiatric drugs in both male and female animals, in order to evaluate the differential response between the two sexes. Notably, while in most cases animal models successfully mimic drug response in both sexes, test parameters and treatment-sensitive behavioural indices are not always the same for male and female rodents. Thus, there is an increasing need to validate animal models for both sexes and use standard procedures across different laboratories. Linked Articles This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20 PMID:24697577

  7. Animal models of polymicrobial pneumonia

    PubMed Central

    Hraiech, Sami; Papazian, Laurent; Rolain, Jean-Marc; Bregeon, Fabienne

    2015-01-01

    Pneumonia is one of the leading causes of severe and occasionally life-threatening infections. The physiopathology of pneumonia has been extensively studied, providing information for the development of new treatments for this condition. In addition to in vitro research, animal models have been largely used in the field of pneumonia. Several models have been described and have provided a better understanding of pneumonia under different settings and with various pathogens. However, the concept of one pathogen leading to one infection has been challenged, and recent flu epidemics suggest that some pathogens exhibit highly virulent potential. Although “two hits” animal models have been used to study infectious diseases, few of these models have been described in pneumonia. Therefore the aims of this review were to provide an overview of the available literature in this field, to describe well-studied and uncommon pathogen associations, and to summarize the major insights obtained from this information. PMID:26170617

  8. Reproducibility Issues: Avoiding Pitfalls in Animal Inflammation Models.

    PubMed

    Laman, Jon D; Kooistra, Susanne M; Clausen, Björn E

    2017-01-01

    In light of an enhanced awareness of ethical questions and ever increasing costs when working with animals in biomedical research, there is a dedicated and sometimes fierce debate concerning the (lack of) reproducibility of animal models and their relevance for human inflammatory diseases. Despite evident advancements in searching for alternatives, that is, replacing, reducing, and refining animal experiments-the three R's of Russel and Burch (1959)-understanding the complex interactions of the cells of the immune system, the nervous system and the affected tissue/organ during inflammation critically relies on in vivo models. Consequently, scientific advancement and ultimately novel therapeutic interventions depend on improving the reproducibility of animal inflammation models. As a prelude to the remaining hands-on protocols described in this volume, here, we summarize potential pitfalls of preclinical animal research and provide resources and background reading on how to avoid them.

  9. Toward a national animal telemetry network for aquatic observations in the United States

    USGS Publications Warehouse

    Block, Barbara A.; Holbrook, Christopher; Simmons, Samantha E; Holland, Kim N; Ault, Jerald S.; Costa, Daniel P.; Mate, Bruce R; Seitz, Andrew C.; Arendt, Michael D.; Payne, John; Mahmoudi, Behzad; Moore, Peter L.; Price, James; J. J. Levenson,; Wilson, Doug; Kochevar, Randall E

    2016-01-01

    Animal telemetry is the science of elucidating the movements and behavior of animals in relation to their environment or habitat. Here, we focus on telemetry of aquatic species (marine mammals, sharks, fish, sea birds and turtles) and so are concerned with animal movements and behavior as they move through and above the world’s oceans, coastal rivers, estuaries and great lakes. Animal telemetry devices (“tags”) yield detailed data regarding animal responses to the coupled ocean–atmosphere and physical environment through which they are moving. Animal telemetry has matured and we describe a developing US Animal Telemetry Network (ATN) observing system that monitors aquatic life on a range of temporal and spatial scales that will yield both short- and long-term benefits, fill oceanographic observing and knowledge gaps and advance many of the U.S. National Ocean Policy Priority Objectives. ATN has the potential to create a huge impact for the ocean observing activities undertaken by the U.S. Integrated Ocean Observing System (IOOS) and become a model for establishing additional national-level telemetry networks worldwide.

  10. Modeling individual animal histories with multistate capture–recapture models

    USGS Publications Warehouse

    Lebreton, Jean-Dominique; Nichols, James D.; Barker, Richard J.; Pradel, Roger; Spendelow, Jeffrey A.

    2009-01-01

    Many fields of science begin with a phase of exploration and description, followed by investigations of the processes that account for observed patterns. The science of ecology is no exception, and recent decades have seen a focus on understanding key processes underlying the dynamics of ecological systems. In population ecology, emphasis has shifted from the state variable of population size to the demographic processes responsible for changes in this state variable: birth, death, immigration, and emigration. In evolutionary ecology, some of these same demographic processes, rates of birth and death, are also the determinants of fitness. In animal population ecology, the estimation of state variables and their associated vital rates is especially problematic because of the difficulties in sampling such populations and detecting individual animals. Indeed, early capture–recapture models were developed for the purpose of estimating population size, given the reality that all animals are not caught or detected at any sampling occasion. More recently, capture–recapture models for open populations were developed to draw inferences about survival in the face of these same sampling problems. The focus of this paper is on multi‐state mark–recapture models (MSMR), which first appeared in the 1970s but have undergone substantial development in the last 15 years. These models were developed to deal explicitly with biological variation, in that animals in different “states” (classes defined by location, physiology, behavior, reproductive status, etc.) may have different probabilities of survival and detection. Animal transitions between states are also stochastic and themselves of interest. These general models have proven to be extremely useful and provide a way of thinking about a remarkably wide range of important ecological processes. These methods are now at a stage of refinement and sophistication where they can readily be used by biologists to tackle a wide

  11. Diabetic aggravation of stroke and animal models

    PubMed Central

    Rehni, Ashish K.; Liu, Allen; Perez-Pinzon, Miguel A.; Dave, Kunjan R.

    2017-01-01

    Cerebral ischemia in diabetics results in severe brain damage. Different animal models of cerebral ischemia have been used to study the aggravation of ischemic brain damage in the diabetic condition. Since different disease conditions such as diabetes differently affect outcome following cerebral ischemia, the Stroke Therapy Academic Industry Roundtable (STAIR) guidelines recommends use of diseased animals for evaluating neuroprotective therapies targeted to reduce cerebral ischemic damage. The goal of this review is to discuss the technicalities and pros/cons of various animal models of cerebral ischemia currently being employed to study diabetes-related ischemic brain damage. The rational use of such animal systems in studying the disease condition may better help evaluate novel therapeutic approaches for diabetes related exacerbation of ischemic brain damage. PMID:28274862

  12. Animal models of drug addiction.

    PubMed

    García Pardo, María Pilar; Roger Sánchez, Concepción; De la Rubia Ortí, José Enrique; Aguilar Calpe, María Asunción

    2017-09-29

    The development of animal models of drug reward and addiction is an essential factor for progress in understanding the biological basis of this disorder and for the identification of new therapeutic targets. Depending on the component of reward to be studied, one type of animal model or another may be used. There are models of reinforcement based on the primary hedonic effect produced by the consumption of the addictive substance, such as the self-administration (SA) and intracranial self-stimulation (ICSS) paradigms, and there are models based on the component of reward related to associative learning and cognitive ability to make predictions about obtaining reward in the future, such as the conditioned place preference (CPP) paradigm. In recent years these models have incorporated methodological modifications to study extinction, reinstatement and reconsolidation processes, or to model specific aspects of addictive behavior such as motivation to consume drugs, compulsive consumption or drug seeking under punishment situations. There are also models that link different reinforcement components or model voluntary motivation to consume (two-bottle choice, or drinking in the dark tests). In short, innovations in these models allow progress in scientific knowledge regarding the different aspects that lead individuals to consume a drug and develop compulsive consumption, providing a target for future treatments of addiction.

  13. Understanding the spatiotemporal pattern of grazing cattle movement

    NASA Astrophysics Data System (ADS)

    Zhao, Kun; Jurdak, Raja

    2016-08-01

    Understanding the drivers of animal movement is significant for ecology and biology. Yet researchers have so far been unable to fully understand these drivers, largely due to low data resolution. In this study, we analyse a high-frequency movement dataset for a group of grazing cattle and investigate their spatiotemporal patterns using a simple two-state ‘stop-and-move’ mobility model. We find that the dispersal kernel in the moving state is best described by a mixture exponential distribution, indicating the hierarchical nature of the movement. On the other hand, the waiting time appears to be scale-invariant below a certain cut-off and is best described by a truncated power-law distribution, suggesting that the non-moving state is governed by time-varying dynamics. We explore possible explanations for the observed phenomena, covering factors that can play a role in the generation of mobility patterns, such as the context of grazing environment, the intrinsic decision-making mechanism or the energy status of different activities. In particular, we propose a new hypothesis that the underlying movement pattern can be attributed to the most probable observable energy status under the maximum entropy configuration. These results are not only valuable for modelling cattle movement but also provide new insights for understanding the underlying biological basis of grazing behaviour.

  14. Energy-information trade-offs between movement and sensing.

    PubMed

    MacIver, Malcolm A; Patankar, Neelesh A; Shirgaonkar, Anup A

    2010-05-06

    While there is accumulating evidence for the importance of the metabolic cost of information in sensory systems, how these costs are traded-off with movement when sensing is closely linked to movement is poorly understood. For example, if an animal needs to search a given amount of space beyond the range of its vision system, is it better to evolve a higher acuity visual system, or evolve a body movement system that can more rapidly move the body over that space? How is this trade-off dependent upon the three-dimensional shape of the field of sensory sensitivity (hereafter, sensorium)? How is it dependent upon sensorium mobility, either through rotation of the sensorium via muscles at the base of the sense organ (e.g., eye or pinna muscles) or neck rotation, or by whole body movement through space? Here we show that in an aquatic model system, the electric fish, a choice to swim in a more inefficient manner during prey search results in a higher prey encounter rate due to better sensory performance. The increase in prey encounter rate more than counterbalances the additional energy expended in swimming inefficiently. The reduction of swimming efficiency for improved sensing arises because positioning the sensory receptor surface to scan more space per unit time results in an increase in the area of the body pushing through the fluid, increasing wasteful body drag forces. We show that the improvement in sensory performance that occurs with the costly repositioning of the body depends upon having an elongated sensorium shape. Finally, we show that if the fish was able to reorient their sensorium independent of body movement, as fish with movable eyes can, there would be significant energy savings. This provides insight into the ubiquity of sensory organ mobility in animal design. This study exposes important links between the morphology of the sensorium, sensorium mobility, and behavioral strategy for maximally extracting energy from the environment. An

  15. Evaluation of acoustic telemetry grids for determining aquatic animal movement and survival

    USGS Publications Warehouse

    Kraus, Richard T.; Holbrook, Christopher; Vandergoot, Christopher; Stewart, Taylor R.; Faust, Matthew D.; Watkinson, Douglas A.; Charles, Colin; Pegg, Mark; Enders, Eva C.; Krueger, Charles C.

    2018-01-01

    Acoustic telemetry studies have frequently prioritized linear configurations of hydrophone receivers, such as perpendicular from shorelines or across rivers, to detect the presence of tagged aquatic animals. This approach introduces unknown bias when receivers are stationed for convenience at geographic bottlenecks (e.g., at the mouth of an embayment or between islands) as opposed to deployments following a statistical sampling design.We evaluated two-dimensional acoustic receiver arrays (grids: receivers spread uniformly across space) as an alternative approach to provide estimates of survival, movement, and habitat use. Performance of variably-spaced receiver grids (5–25 km spacing) was evaluated by simulating (1) animal tracks as correlated random walks (speed: 0.1–0.9 m/s; turning angle standard deviation: 5–30 degrees); (2) variable tag transmission intervals along each track (nominal delay: 15–300 seconds); and (3) probability of detection of each transmission based on logistic detection range curves (midpoint: 200–1500 m). From simulations, we quantified i) time between successive detections on any receiver (detection time), ii) time between successive detections on different receivers (transit time), and iii) distance between successive detections on different receivers (transit distance).In the most restrictive detection range scenario (200 m), the 95th percentile of transit time was 3.2 days at 5 km grid spacing, 5.7 days at 7 km, and 15.2 days at 25 km; for the 1500 m detection range scenario, it was 0.1 days at 5 km, 0.5 days at 7 km, and 10.8 days at 25 km. These values represented upper bounds on the expected maximum time that an animal could go undetected. Comparison of the simulations with pilot studies on three fishes (walleye Sander vitreus, common carp Cyprinus carpio, and channel catfish Ictalurus punctatus) from two independent large lake ecosystems (lakes Erie and Winnipeg) revealed shorter detection and transit times than what

  16. Quantifying drivers of wild pig movement across multiple spatial and temporal scales.

    PubMed

    Kay, Shannon L; Fischer, Justin W; Monaghan, Andrew J; Beasley, James C; Boughton, Raoul; Campbell, Tyler A; Cooper, Susan M; Ditchkoff, Stephen S; Hartley, Steve B; Kilgo, John C; Wisely, Samantha M; Wyckoff, A Christy; VerCauteren, Kurt C; Pepin, Kim M

    2017-01-01

    The movement behavior of an animal is determined by extrinsic and intrinsic factors that operate at multiple spatio-temporal scales, yet much of our knowledge of animal movement comes from studies that examine only one or two scales concurrently. Understanding the drivers of animal movement across multiple scales is crucial for understanding the fundamentals of movement ecology, predicting changes in distribution, describing disease dynamics, and identifying efficient methods of wildlife conservation and management. We obtained over 400,000 GPS locations of wild pigs from 13 different studies spanning six states in southern U.S.A., and quantified movement rates and home range size within a single analytical framework. We used a generalized additive mixed model framework to quantify the effects of five broad predictor categories on movement: individual-level attributes, geographic factors, landscape attributes, meteorological conditions, and temporal variables. We examined effects of predictors across three temporal scales: daily, monthly, and using all data during the study period. We considered both local environmental factors such as daily weather data and distance to various resources on the landscape, as well as factors acting at a broader spatial scale such as ecoregion and season. We found meteorological variables (temperature and pressure), landscape features (distance to water sources), a broad-scale geographic factor (ecoregion), and individual-level characteristics (sex-age class), drove wild pig movement across all scales, but both the magnitude and shape of covariate relationships to movement differed across temporal scales. The analytical framework we present can be used to assess movement patterns arising from multiple data sources for a range of species while accounting for spatio-temporal correlations. Our analyses show the magnitude by which reaction norms can change based on the temporal scale of response data, illustrating the importance of

  17. Basic mechanisms of MCD in animal models.

    PubMed

    Battaglia, Giorgio; Becker, Albert J; LoTurco, Joseph; Represa, Alfonso; Baraban, Scott C; Roper, Steven N; Vezzani, Annamaria

    2009-09-01

    Epilepsy-associated glioneuronal malformations (malformations of cortical development [MCD]) include focal cortical dysplasias (FCD) and highly differentiated glioneuronal tumors, most frequently gangliogliomas. The neuropathological findings are variable but suggest aberrant proliferation, migration, and differentiation of neural precursor cells as essential pathogenetic elements. Recent advances in animal models for MCDs allow new insights in the molecular pathogenesis of these epilepsy-associated lesions. Novel approaches, presented here, comprise RNA interference strategies to generate and study experimental models of subcortical band heterotopia and study functional aspects of aberrantly shaped and positioned neurons. Exciting analyses address impaired NMDA receptor expression in FCD animal models compared to human FCDs and excitatory imbalances in MCD animal models such as lissencephaly gene ablated mice as well as in utero irradiated rats. An improved understanding of relevant pathomechanisms will advance the development of targeted treatment strategies for epilepsy-associated malformations.

  18. Animating Preservice Teachers' Noticing

    ERIC Educational Resources Information Center

    de Araujo, Zandra; Amador, Julie; Estapa, Anne; Weston, Tracy; Aming-Attai, Rachael; Kosko, Karl W.

    2015-01-01

    The incorporation of animation in mathematics teacher education courses is one method for transforming practices and promoting practice-based education. Animation can be used as an approximation of practice that engages preservice teachers (PSTs) in creating classroom scenes in which they select characters, regulate movement, and construct…

  19. Osteoporotic Animal Models of Bone Healing: Advantages and Pitfalls.

    PubMed

    Calciolari, Elena; Donos, Nikolaos; Mardas, Nikos

    2017-10-01

    The aim of this review was to summarize the advantages and pitfalls of the available osteoporotic animal models of bone healing. A thorough literature search was performed in MEDLINE via OVID and EMBASE to identify animal studies investigating the effect of experimental osteoporosis on bone healing and bone regeneration. The osteotomy model in the proximal tibia is the most popular osseous defect model to study the bone healing process in osteoporotic-like conditions, although other well-characterized models, such as the post-extraction model, might be taken into consideration by future studies. The regenerative potential of osteoporotic bone and its response to biomaterials/regenerative techniques has not been clarified yet, and the critical size defect model might be an appropriate tool to serve this purpose. Since an ideal animal model for simulating osteoporosis does not exist, the type of bone remodeling, the animal lifespan, the age of peak bone mass, and the economic and ethical implications should be considered in our selection process. Furthermore, the influence of animal species, sex, age, and strain on the outcome measurement should be taken into account. In order to make future studies meaningful, standardized international guidelines for osteoporotic animal models of bone healing need to be set up.

  20. Modelling nematode movement using time-fractional dynamics.

    PubMed

    Hapca, Simona; Crawford, John W; MacMillan, Keith; Wilson, Mike J; Young, Iain M

    2007-09-07

    We use a correlated random walk model in two dimensions to simulate the movement of the slug parasitic nematode Phasmarhabditis hermaphrodita in homogeneous environments. The model incorporates the observed statistical distributions of turning angle and speed derived from time-lapse studies of individual nematode trails. We identify strong temporal correlations between the turning angles and speed that preclude the case of a simple random walk in which successive steps are independent. These correlated random walks are appropriately modelled using an anomalous diffusion model, more precisely using a fractional sub-diffusion model for which the associated stochastic process is characterised by strong memory effects in the probability density function.

  1. Dynamic model of the octopus arm. II. Control of reaching movements.

    PubMed

    Yekutieli, Yoram; Sagiv-Zohar, Roni; Hochner, Binyamin; Flash, Tamar

    2005-08-01

    The dynamic model of the octopus arm described in the first paper of this 2-part series was used here to investigate the neural strategies used for controlling the reaching movements of the octopus arm. These are stereotypical extension movements used to reach toward an object. In the dynamic model, sending a simple propagating neural activation signal to contract all muscles along the arm produced an arm extension with kinematic properties similar to those of natural movements. Control of only 2 parameters fully specified the extension movement: the amplitude of the activation signal (leading to the generation of muscle force) and the activation traveling time (the time the activation wave takes to travel along the arm). We found that the same kinematics could be achieved by applying activation signals with different activation amplitudes all exceeding some minimal level. This suggests that the octopus arm could use minimal amplitudes of activation to generate the minimal muscle forces required for the production of the desired kinematics. Larger-amplitude signals would generate larger forces that increase the arm's stability against perturbations without changing the kinematic characteristics. The robustness of this phenomenon was demonstrated by examining activation signals with either a constant or a bell-shaped velocity profile. Our modeling suggests that the octopus arm biomechanics may allow independent control of kinematics and resistance to perturbation during arm extension movements.

  2. A neural command circuit for grooming movement control.

    PubMed

    Hampel, Stefanie; Franconville, Romain; Simpson, Julie H; Seeds, Andrew M

    2015-09-07

    Animals perform many stereotyped movements, but how nervous systems are organized for controlling specific movements remains unclear. Here we use anatomical, optogenetic, behavioral, and physiological techniques to identify a circuit in Drosophila melanogaster that can elicit stereotyped leg movements that groom the antennae. Mechanosensory chordotonal neurons detect displacements of the antennae and excite three different classes of functionally connected interneurons, which include two classes of brain interneurons and different parallel descending neurons. This multilayered circuit is organized such that neurons within each layer are sufficient to specifically elicit antennal grooming. However, we find differences in the durations of antennal grooming elicited by neurons in the different layers, suggesting that the circuit is organized to both command antennal grooming and control its duration. As similar features underlie stimulus-induced movements in other animals, we infer the possibility of a common circuit organization for movement control that can be dissected in Drosophila.

  3. A review of simulation modelling approaches used for the spread of zoonotic influenza viruses in animal and human populations.

    PubMed

    Dorjee, S; Poljak, Z; Revie, C W; Bridgland, J; McNab, B; Leger, E; Sanchez, J

    2013-09-01

    Increasing incidences of emerging and re-emerging diseases that are mostly zoonotic (e.g. severe acute respiratory syndrome, avian influenza H5N1, pandemic influenza) has led to the need for a multidisciplinary approach to tackling these threats to public and animal health. Accordingly, a global movement of 'One-Health/One-Medicine' has been launched to foster collaborative efforts amongst animal and human health officials and researchers to address these problems. Historical evidence points to the fact that pandemics caused by influenza A viruses remain a major zoonotic threat to mankind. Recently, a range of mathematical and computer simulation modelling methods and tools have increasingly been applied to improve our understanding of disease transmission dynamics, contingency planning and to support policy decisions on disease outbreak management. This review provides an overview of methods, approaches and software used for modelling the spread of zoonotic influenza viruses in animals and humans, particularly those related to the animal-human interface. Modelling parameters used in these studies are summarized to provide references for future work. This review highlights the limited application of modelling research to influenza in animals and at the animal-human interface, in marked contrast to the large volume of its research in human populations. Although swine are widely recognized as a potential host for generating novel influenza viruses, and that some of these viruses, including pandemic influenza A/H1N1 2009, have been shown to be readily transmissible between humans and swine, only one study was found related to the modelling of influenza spread at the swine-human interface. Significant gaps in the knowledge of frequency of novel viral strains evolution in pigs, farm-level natural history of influenza infection, incidences of influenza transmission between farms and between swine and humans are clearly evident. Therefore, there is a need to direct

  4. Organization of octopus arm movements: a model system for studying the control of flexible arms.

    PubMed

    Gutfreund, Y; Flash, T; Yarom, Y; Fiorito, G; Segev, I; Hochner, B

    1996-11-15

    Octopus arm movements provide an extreme example of controlled movements of a flexible arm with virtually unlimited degrees of freedom. This study aims to identify general principles in the organization of these movements. Video records of the movements of Octopus vulgaris performing the task of reaching toward a target were studied. The octopus extends its arm toward the target by a wave-like propagation of a bend that travels from the base of the arm toward the tip. Similar bend propagation is seen in other octopus arm movements, such as locomotion and searching. The kinematics (position and velocity) of the midpoint of the bend in three-dimensional space were extracted using the direct linear transformation algorithm. This showed that the bend tends to move within a single linear plane in a simple, slightly curved path connecting the center of the animal's body with the target location. Approximately 70% of the reaching movements demonstrated a stereotyped tangential velocity profile. An invariant profile was observed when movements were normalized for velocity and distance. Two arms, extended together in the same behavioral context, demonstrated identical velocity profiles. The stereotyped features of the movements were also observed in spontaneous arm extensions (not toward an external target). The simple and stereotypic appearance of the bend trajectory suggests that the position of the bend in space and time is the controlled variable. We propose that this strategy reduces the immense redundancy of the octopus arm movements and hence simplifies motor control.

  5. Create your own stimulus: Manipulating movements according to social categories

    PubMed Central

    Koppensteiner, Markus; Primes, Georg; Stephan, Pia

    2017-01-01

    People ascribe purposeful behaviour to the movements of artificial objects and social qualities to human body motion. We investigated how people associate simple motion cues with social categories. For a first rating-experiment we converted the body movements of speakers into stick-figure animations; for a second rating-experiment we used animations of one single dot. Rating-experiments were “reversed” because we asked participants to alter the movements (i.e., vertical amplitude, horizontal amplitude, and velocity) of the stimuli according to different instructions (e.g., create a stimulus of high dominance). Participants equipped stick figures and dot animations with expansive movements to represent high dominance. Expansive and fast movements (i.e., high velocity) were mainly associated with high aggressiveness. Fast movements were also associated with low friendliness, low trustworthiness, and low competence. Overall, patterns found for stick figure and dot animations were similar indicating that certain motion cues convey social information even when only a dot and no body form is visible. The “reverse approach” we propose here makes the impact of different components directly observable. The data generated by this method offers better insights into the interplay of these components and the ways in which they form meaningful patterns. The proposed method can be extended to other types of nonverbal cues and a variety of social categories. PMID:28339490

  6. 9 CFR 329.5 - Movement of article or livestock detained; removal of official marks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Movement of article or livestock detained; removal of official marks. 329.5 Section 329.5 Animals and Animal Products FOOD SAFETY AND... it is located when so detained, for refrigeration, freezing, or storage purposes if such movement has...

  7. Reviewing model application to support animal health decision making.

    PubMed

    Singer, Alexander; Salman, Mo; Thulke, Hans-Hermann

    2011-04-01

    Animal health is of societal importance as it affects human welfare, and anthropogenic interests shape decision making to assure animal health. Scientific advice to support decision making is manifold. Modelling, as one piece of the scientific toolbox, is appreciated for its ability to describe and structure data, to give insight in complex processes and to predict future outcome. In this paper we study the application of scientific modelling to support practical animal health decisions. We reviewed the 35 animal health related scientific opinions adopted by the Animal Health and Animal Welfare Panel of the European Food Safety Authority (EFSA). Thirteen of these documents were based on the application of models. The review took two viewpoints, the decision maker's need and the modeller's approach. In the reviewed material three types of modelling questions were addressed by four specific model types. The correspondence between tasks and models underpinned the importance of the modelling question in triggering the modelling approach. End point quantifications were the dominating request from decision makers, implying that prediction of risk is a major need. However, due to knowledge gaps corresponding modelling studies often shed away from providing exact numbers. Instead, comparative scenario analyses were performed, furthering the understanding of the decision problem and effects of alternative management options. In conclusion, the most adequate scientific support for decision making - including available modelling capacity - might be expected if the required advice is clearly stated. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Real Time 3D Facial Movement Tracking Using a Monocular Camera.

    PubMed

    Dong, Yanchao; Wang, Yanming; Yue, Jiguang; Hu, Zhencheng

    2016-07-25

    The paper proposes a robust framework for 3D facial movement tracking in real time using a monocular camera. It is designed to estimate the 3D face pose and local facial animation such as eyelid movement and mouth movement. The framework firstly utilizes the Discriminative Shape Regression method to locate the facial feature points on the 2D image and fuses the 2D data with a 3D face model using Extended Kalman Filter to yield 3D facial movement information. An alternating optimizing strategy is adopted to fit to different persons automatically. Experiments show that the proposed framework could track the 3D facial movement across various poses and illumination conditions. Given the real face scale the framework could track the eyelid with an error of 1 mm and mouth with an error of 2 mm. The tracking result is reliable for expression analysis or mental state inference.

  9. Classic and new animal models of Parkinson's disease.

    PubMed

    Blesa, Javier; Phani, Sudarshan; Jackson-Lewis, Vernice; Przedborski, Serge

    2012-01-01

    Neurological disorders can be modeled in animals so as to recreate specific pathogenic events and behavioral outcomes. Parkinson's Disease (PD) is the second most common neurodegenerative disease of an aging population, and although there have been several significant findings about the PD disease process, much of this process still remains a mystery. Breakthroughs in the last two decades using animal models have offered insights into the understanding of the PD disease process, its etiology, pathology, and molecular mechanisms. Furthermore, while cellular models have helped to identify specific events, animal models, both toxic and genetic, have replicated almost all of the hallmarks of PD and are useful for testing new neuroprotective or neurorestorative strategies. Moreover, significant advances in the modeling of additional PD features have come to light in both classic and newer models. In this review, we try to provide an updated summary of the main characteristics of these models as well as the strengths and weaknesses of what we believe to be the most popular PD animal models. These models include those produced by 6-hydroxydopamine (6-OHDA), 1-methyl-1,2,3,6-tetrahydropiridine (MPTP), rotenone, and paraquat, as well as several genetic models like those related to alpha-synuclein, PINK1, Parkin and LRRK2 alterations.

  10. Using physical models to study the gliding performance of extinct animals.

    PubMed

    Koehl, M A R; Evangelista, Dennis; Yang, Karen

    2011-12-01

    Aerodynamic studies using physical models of fossil organisms can provide quantitative information about how performance of defined activities, such as gliding, depends on specific morphological features. Such analyses allow us to rule out hypotheses about the function of extinct organisms that are not physically plausible and to determine if and how specific morphological features and postures affect performance. The purpose of this article is to provide a practical guide for the design of dynamically scaled physical models to study the gliding of extinct animals using examples from our research on the theropod dinosaur, †Microraptor gui, which had flight feathers on its hind limbs as well as on its forelimbs. Analysis of the aerodynamics of †M. gui can shed light on the design of gliders with large surfaces posterior to the center of mass and provide functional information to evolutionary biologists trying to unravel the origins of flight in the dinosaurian ancestors and sister groups to birds. Measurements of lift, drag, side force, and moments in pitch, roll, and yaw on models in a wind tunnel can be used to calculate indices of gliding and parachuting performance, aerodynamic static stability, and control effectiveness in maneuvering. These indices permit the aerodynamic performance of bodies of different shape, size, stiffness, texture, and posture to be compared and thus can provide insights about the design of gliders, both biological and man-made. Our measurements of maximum lift-to-drag ratios of 2.5-3.1 for physical models of †M. gui suggest that its gliding performance was similar to that of flying squirrels and that the various leg postures that might have been used by †M. gui make little difference to that aspect of aerodynamic performance. We found that body orientation relative to the movement of air past the animal determines whether it is difficult or easy to maneuver.

  11. Pipelines subject to slow landslide movements: Structural modeling vs field measurement

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

    Bruschi, R.; Glavina, S.; Spinazze, M.

    1996-12-01

    In recent years finite element techniques have been increasingly used to investigate the behavior of buried pipelines subject to soil movements. The use of these tools provides a rational basis for the definition of minimum wall thickness requirements in landslide crossings. Furthermore the design of mitigation measures or monitoring systems which control the development of undesirable strains in the pipe wall over time, requires a detailed structural modeling. The scope of this paper is to discuss the use of dedicated structural modeling with relevant calibration to field measurements. The strain measurements used were regularly gathered from pipe sections, in twomore » different sites over a period of time long enough to record changes of axial strain due to soil movement. Detailed structural modeling of pipeline layout in both sites and for operating conditions, is applied. Numerical simulations show the influence of the distribution of soil movement acting on the pipeline with regards to the state of strain which can be developed in certain locations. The role of soil nature and direction of relative movements in the definition of loads transferred to the pipeline, is also discussed.« less

  12. Synapse alterations in autism: Review of animal model findings.

    PubMed

    Zatkova, Martina; Bakos, Jan; Hodosy, Julius; Ostatnikova, Daniela

    2016-06-01

    Recent research has produced an explosion of experimental data on the complex neurobiological mechanisms of developmental disorders including autism. Animal models are one approach to studying the phenotypic features and molecular basis of autism. In this review, we describe progress in understanding synaptogenesis and alterations to this process with special emphasis on the cell adhesion molecules and scaffolding proteins implicated in autism. Genetic mouse model experiments are discussed in relation to alterations to selected synaptic proteins and consequent behavioral deficits measured in animal experiments. Pubmed databases were used to search for original and review articles on animal and human clinical studies on autism. The cell adhesion molecules, neurexin, neurolignin and the Shank family of proteins are important molecular targets associated with autism. The heterogeneity of the autism spectrum of disorders limits interpretation of information acquired from any single animal model or animal test. We showed synapse-specific/ model-specific defects associated with a given genotype in these models. Characterization of mouse models with genetic variations may help study the mechanisms of autism in humans. However, it will be necessary to apply new analytic paradigms in using genetically modified mice for understanding autism etiology in humans. Further studies are needed to create animal models with mutations that match the molecular and neural bases of autism.

  13. Animal models in plastic and reconstructive surgery simulation-a review.

    PubMed

    Loh, Charles Yuen Yung; Wang, Aline Yen Ling; Tiong, Vincent Tze Yang; Athanassopoulos, Thanassi; Loh, Meiling; Lim, Philip; Kao, Huang-Kai

    2018-01-01

    The use of live and cadaveric animal models in surgical training is well established as a means of teaching and improving surgical skill in a controlled setting. We aim to review, evaluate, and summarize the models published in the literature that are applicable to Plastic Surgery training. A PubMed search for keywords relating to animal models in Plastic Surgery and the associated procedures was conducted. Animal models that had cross over between specialties such as microsurgery with Neurosurgery and pinnaplasty with ear, nose, and throat surgery were included as they were deemed to be relevant to our training curriculum. A level of evidence and recommendation assessment was then given to each surgical model. Our review found animal models applicable to plastic surgery training in four major categories namely-microsurgery training, flap raising, facial surgery, and hand surgery. Twenty-four separate articles described various methods of practicing microsurgical techniques on different types of animals. Fourteen different articles each described various methods of conducting flap-based procedures which consisted of either local or perforator flap dissection. Eight articles described different models for practicing hand surgery techniques. Finally, eight articles described animal models that were used for head and neck procedures. A comprehensive summary of animal models related to plastic surgery training has been compiled. Cadaveric animal models provide a readily available introduction to many procedures and ought to be used instead of live models when feasible. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Animal models in the research of abdominal aortic aneurysms development.

    PubMed

    Patelis, N; Moris, D; Schizas, D; Damaskos, C; Perrea, D; Bakoyiannis, C; Liakakos, T; Georgopoulos, S

    2017-12-20

    Abdominal aortic aneurysm (AAA) is a prevalent and potentially life threatening disease. Many animal models have been developed to simulate the natural history of the disease or test preclinical endovascular devices and surgical procedures. The aim of this review is to describe different methods of AAA induction in animal models and report on the effectiveness of the methods described in inducing an analogue of a human AAA. The PubMed database was searched for publications with titles containing the following terms "animal" or "animal model(s)" and keywords "research", "aneurysm(s)", "aorta", "pancreatic elastase", "Angiotensin", "AngII" "calcium chloride" or "CaCl(2)". Starting date for this search was set to 2004, since previously bibliography was already covered by the review of Daugherty and Cassis (2004). We focused on animal studies that reported a model of aneurysm development and progression. A number of different approaches of AAA induction in animal models has been developed, used and combined since the first report in the 1960's. Although specific methods are successful in AAA induction in animal models, it is necessary that these methods and their respective results are in line with the pathophysiology and the mechanisms involved in human AAA development. A researcher should know the advantages/disadvantages of each animal model and choose the appropriate model.

  15. Computational Model-Based Prediction of Human Episodic Memory Performance Based on Eye Movements

    NASA Astrophysics Data System (ADS)

    Sato, Naoyuki; Yamaguchi, Yoko

    Subjects' episodic memory performance is not simply reflected by eye movements. We use a ‘theta phase coding’ model of the hippocampus to predict subjects' memory performance from their eye movements. Results demonstrate the ability of the model to predict subjects' memory performance. These studies provide a novel approach to computational modeling in the human-machine interface.

  16. Animal models of post-traumatic epilepsy.

    PubMed

    Ostergard, Thomas; Sweet, Jennifer; Kusyk, Dorian; Herring, Eric; Miller, Jonathan

    2016-10-15

    Post-traumatic epilepsy (PTE) is defined as the development of unprovoked seizures in a delayed fashion after traumatic brain injury (TBI). PTE lies at the intersection of two distinct fields of study, epilepsy and neurotrauma. TBI is associated with a myriad of both focal and diffuse anatomic injuries, and an ideal animal model of epilepsy after TBI must mimic the characteristics of human PTE. The three most commonly used models of TBI are lateral fluid percussion, controlled cortical injury, and weight drop. Much of what is known about PTE has resulted from use of these models. In this review, we describe the most commonly used animal models of TBI with special attention to their advantages and disadvantages with respect to their use as a model of PTE. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Group choreography: mechanisms orchestrating the collective movement of border cells

    PubMed Central

    Montell, Denise J.; Yoon, Wan Hee; Starz-Gaiano, Michelle

    2014-01-01

    Cell movements are essential for animal development and homeostasis but also contribute to disease. Moving cells typically extend protrusions towards a chemoattractant, adhere to the substrate, contract and detach at the rear. It is less clear how cells that migrate in interconnected groups in vivo coordinate their behaviour and navigate through natural environments. The border cells of the Drosophila melanogaster ovary have emerged as an excellent model for the study of collective cell movement, aided by innovative genetic, live imaging, and photomanipulation techniques. Here we provide an overview of the molecular choreography of border cells and its more general implications. PMID:23000794

  18. Recent advances in animal model experimentation in autism research.

    PubMed

    Tania, Mousumi; Khan, Md Asaduzzaman; Xia, Kun

    2014-10-01

    Autism, a lifelong neuro-developmental disorder is a uniquely human condition. Animal models are not the perfect tools for the full understanding of human development and behavior, but they can be an important place to start. This review focused on the recent updates of animal model research in autism. We have reviewed the publications over the last three decades, which are related to animal model study in autism. Animal models are important because they allow researchers to study the underlying neurobiology in a way that is not possible in humans. Improving the availability of better animal models will help the field to increase the development of medicines that can relieve disabling symptoms. Results from the therapeutic approaches are encouraging remarkably, since some behavioral alterations could be reversed even when treatment was performed on adult mice. Finding an animal model system with similar behavioral tendencies as humans is thus vital for understanding the brain mechanisms, supporting social motivation and attention, and the manner in which these mechanisms break down in autism. The ongoing studies should therefore increase the understanding of the biological alterations associated with autism as well as the development of knowledge-based treatments therapy for those struggling with autism. In this review, we have presented recent advances in research based on animal models of autism, raising hope for understanding the disease biology for potential therapeutic intervention to improve the quality of life of autism individuals.

  19. Movement behavior preceding autumn mortality for white-tailed deer in central New York

    USGS Publications Warehouse

    Whitman, Brigham J.; Porter, W. F.; Dechen Quinn, Amy C.; Williams, David M.; Frair, Jacqueline L.; Underwood, Harold; Crawford, Joanne C.

    2018-01-01

    A common yet largely untested assumption in the theory of animal movements is that increased rates and a wider range of movements, such as occurs during breeding, make animals more vulnerable to mortality. We examined mortality among 34 white-tailed deer (Odocoileus virginianus) wearing GPS collars during the autumn breeding season of 2006 and 2007 in a heavily hunted, forest-agricultural landscape of central New York state. We evaluated whether individuals having higher rates of movement incurred higher rates of mortality and whether mortality risk was higher when deer were in less familiar areas. We used a Cox proportional hazards model to analyze how mortality risk changes with movement rates measured over 3 time periods: < 1 day, up to 2 weeks prior to death, and 3–4 weeks prior to death. Overall, deer increased their movement rates as autumn progressed, males more so than females. However, deer that died moved at a slower rate relative to surviving deer up to 2 weeks prior to death (ß = -2.22 ± 0.81; 95% confidence interval [CI] = -3.91 to -0.51) and a slower rate on their day of death compared to deer that survived (ß = -1.77 ± 0.73; 95% CI = -3.19 to -0.33). Site familiarity was not significantly related to mortality risk. Deer were equally likely to die within their 50% core use area as elsewhere within their autumn home range. We hypothesize that increased sociality associated with breeding may make animals more vulnerable to harvest mortality. Our findings contradict general assumptions about the influences of movement behavior on mortality risk, suggesting that patterns may be sensitive to the spatiotemporal context of the movement analysis.

  20. Models for extracting vertical crustal movements from leveling data

    NASA Technical Reports Server (NTRS)

    Holdahl, S. H.

    1978-01-01

    Various adjustment strategies are being used in North America to obtain vertical crustal movements from repeated leveling. The more successful models utilize polynomials or multiquadric analysis to describe elevation change with a velocity surface. Other features permit determination of nonlinear motions, motions associated with earthquakes or episodes, and vertical motions of blocks where boundaries are prespecified. The preferred models for estimating crustal motions permit the use of detached segments of releveling to govern the shape of a velocity surface and allow for input from nonleveling sources such as tide gages and paired lake gages. Some models for extracting vertical crustal movements from releveling data are also excellent for adjusting leveling networks, and permit mixing old and new data in areas exhibiting vertical motion. The new adjustment techniques are more general than older static models and will undoubtedly be used routinely in the future as the constitution of level networks becomes mainly relevelings.

  1. Cytomegalovirus Antivirals and Development of Improved Animal Models

    PubMed Central

    McGregor, Alistair; Choi, K. Yeon

    2015-01-01

    Introduction Cytomegalovirus (CMV) is a ubiquitous pathogen that establishes a life long asymptomatic infection in healthy individuals. Infection of immunesuppressed individuals causes serious illness. Transplant and AIDS patients are highly susceptible to CMV leading to life threatening end organ disease. Another vulnerable population is the developing fetus in utero, where congenital infection can result in surviving newborns with long term developmental problems. There is no vaccine licensed for CMV and current antivirals suffer from complications associated with prolonged treatment. These include drug toxicity and emergence of resistant strains. There is an obvious need for new antivirals. Candidate intervention strategies are tested in controlled pre-clinical animal models but species specificity of HCMV precludes the direct study of the virus in an animal model. Areas covered This review explores the current status of CMV antivirals and development of new drugs. This includes the use of animal models and the development of new improved models such as humanized animal CMV and bioluminescent imaging of virus in animals in real time. Expert Opinion Various new CMV antivirals are in development, some with greater spectrum of activity against other viruses. Although the greatest need is in the setting of transplant patients there remains an unmet need for a safe antiviral strategy against congenital CMV. This is especially important since an effective CMV vaccine remains an elusive goal. In this capacity greater emphasis should be placed on suitable pre-clinical animal models and greater collaboration between industry and academia. PMID:21883024

  2. Satellite Animation Shows Nate's Landfall and Movement North

    NASA Image and Video Library

    2017-10-09

    This animation of NOAA's GOES East and West satellite imagery from Oct. 9 at 5:30 a.m. EDT (0930 UTC) to Oct 9 at 7:30 a.m. EDT (1130 UTC) shows Hurricane Nate make landfall at the mouth of the Mississippi River on Oct. 7 at 8 p.m. EDT. The animation ends with Post-Tropical Cyclone Nate centered over the Ohio Valley but bringing rainfall to the Mid-Atlantic and the northeastern U.S.

  3. Nonmurine animal models of food allergy.

    PubMed

    Helm, Ricki M; Ermel, Richard W; Frick, Oscar L

    2003-02-01

    Food allergy can present as immediate hypersensitivity [manifestations mediated by immunoglobulin (Ig)E], delayed-type hypersensitivity (reactions associated with specific T lymphocytes), and inflammatory reactions caused by immune complexes. For reasons of ethics and efficacy, investigations in humans to determine sensitization and allergic responses of IgE production to innocuous food proteins are not feasible. Therefore, animal models are used a) to bypass the innate tendency to develop tolerance to food proteins and induce specific IgE antibody of sufficient avidity/affinity to cause sensitization and upon reexposure to induce an allergic response, b) to predict allergenicity of novel proteins using characteristics of known food allergens, and c) to treat food allergy by using immunotherapeutic strategies to alleviate life-threatening reactions. The predominant hypothesis for IgE-mediated food allergy is that there is an adverse reaction to exogenous food proteins or food protein fragments, which escape lumen hydrolysis, and in a polarized helper T cell subset 2 (Th2) environment, immunoglobulin class switching to allergen-specific IgE is generated in the immune system of the gastrointestinal-associated lymphoid tissues. Traditionally, the immunologic characterization and toxicologic studies of small laboratory animals have provided the basis for development of animal models of food allergy; however, the natural allergic response in large animals, which closely mimic allergic diseases in humans, can also be useful as models for investigations involving food allergy.

  4. Use of Animal Models to Develop Antiaddiction Medications

    PubMed Central

    Gardner, Eliot L.

    2008-01-01

    Although addiction is a uniquely human phenomenon, some of its pathognomonic features can be modeled at the animal level. Such features include the euphoric “high” produced by acute administration of addictive drugs; the dysphoric “crash” produced by acute withdrawal, drug-seeking, and drug-taking behaviors; and relapse to drug-seeking behavior after achieving successful abstinence. Animal models exist for each of these features. In this review, I focus on various animal models of addiction and how they can be used to search for clinically effective antiaddiction medications. I conclude by noting some of the new and novel medications that have been developed preclinically using such models and the hope for further developments along such lines. PMID:18803910

  5. Facial movements strategically camouflage involuntary social signals of face morphology.

    PubMed

    Gill, Daniel; Garrod, Oliver G B; Jack, Rachael E; Schyns, Philippe G

    2014-05-01

    Animals use social camouflage as a tool of deceit to increase the likelihood of survival and reproduction. We tested whether humans can also strategically deploy transient facial movements to camouflage the default social traits conveyed by the phenotypic morphology of their faces. We used the responses of 12 observers to create models of the dynamic facial signals of dominance, trustworthiness, and attractiveness. We applied these dynamic models to facial morphologies differing on perceived dominance, trustworthiness, and attractiveness to create a set of dynamic faces; new observers rated each dynamic face according to the three social traits. We found that specific facial movements camouflage the social appearance of a face by modulating the features of phenotypic morphology. A comparison of these facial expressions with those similarly derived for facial emotions showed that social-trait expressions, rather than being simple one-to-one overgeneralizations of emotional expressions, are a distinct set of signals composed of movements from different emotions. Our generative face models represent novel psychophysical laws for social sciences; these laws predict the perception of social traits on the basis of dynamic face identities.

  6. Dynamic social networks based on movement

    USGS Publications Warehouse

    Scharf, Henry; Hooten, Mevin B.; Fosdick, Bailey K.; Johnson, Devin S.; London, Joshua M.; Durban, John W.

    2016-01-01

    Network modeling techniques provide a means for quantifying social structure in populations of individuals. Data used to define social connectivity are often expensive to collect and based on case-specific, ad hoc criteria. Moreover, in applications involving animal social networks, collection of these data is often opportunistic and can be invasive. Frequently, the social network of interest for a given population is closely related to the way individuals move. Thus, telemetry data, which are minimally invasive and relatively inexpensive to collect, present an alternative source of information. We develop a framework for using telemetry data to infer social relationships among animals. To achieve this, we propose a Bayesian hierarchical model with an underlying dynamic social network controlling movement of individuals via two mechanisms: an attractive effect and an aligning effect. We demonstrate the model and its ability to accurately identify complex social behavior in simulation, and apply our model to telemetry data arising from killer whales. Using auxiliary information about the study population, we investigate model validity and find the inferred dynamic social network is consistent with killer whale ecology and expert knowledge.

  7. Incorporating in situ habitat patchiness in site selection models reveals that site fidelity is not always a consequence of animal choice.

    PubMed

    Martinez, Aline S; Queiroz, Eduardo V; Bryson, Mitch; Byrne, Maria; Coleman, Ross A

    2017-07-01

    Understanding site fidelity is important in animal ecology, but evidence is lacking that this behaviour is due to an animal choosing a specific location. To discern site selection behaviour, it is necessary to consider the spatial distribution of habitats that animals can occupy within a landscape. Tracking animals and defining clear habitat boundaries, however, is often difficult. We use in situ habitat distribution data and animal movement simulations to investigate behavioural choice in site fidelity patterns. We resolved the difficulty of gathering data by working with intertidal rock pool systems, which are of manageable size and where boundaries are easy to define. Movements of the intertidal starfish Parvulastra exigua were quantified to test the hypotheses that (1) this species displays fidelity to a particular rock pool and that (2) rock pool fidelity is due to site selection behaviour. Observed patterns of individuals (n = 10 starfish) returning to a previously occupied rock pool (n = 5 pools per location) were tested against an expected null distribution generated through simulations of random movements within their natural patchy environment. Starfish exhibited site selection behaviour at only one location even though site fidelity was high (av. 7·4 starfish out of 10 found in test pools) in two of the three locations. The random chance of a starfish returning to a pool increased 67% for each metre further a rock pool was from the original pool, and 120% for each square metre increase in surface area of an original pool. The decision of returning to an original rock pool was influenced by food availability. When microalgal cover was >60%, there was a c. 50% chance of animals staying faithful to that pool. Our results show the importance to consider spatial distribution of habitats in understanding patterns of animal movement associated with animal choices and site fidelity. Returning to a particular place does not necessarily mean that an animal

  8. Software Validation via Model Animation

    NASA Technical Reports Server (NTRS)

    Dutle, Aaron M.; Munoz, Cesar A.; Narkawicz, Anthony J.; Butler, Ricky W.

    2015-01-01

    This paper explores a new approach to validating software implementations that have been produced from formally-verified algorithms. Although visual inspection gives some confidence that the implementations faithfully reflect the formal models, it does not provide complete assurance that the software is correct. The proposed approach, which is based on animation of formal specifications, compares the outputs computed by the software implementations on a given suite of input values to the outputs computed by the formal models on the same inputs, and determines if they are equal up to a given tolerance. The approach is illustrated on a prototype air traffic management system that computes simple kinematic trajectories for aircraft. Proofs for the mathematical models of the system's algorithms are carried out in the Prototype Verification System (PVS). The animation tool PVSio is used to evaluate the formal models on a set of randomly generated test cases. Output values computed by PVSio are compared against output values computed by the actual software. This comparison improves the assurance that the translation from formal models to code is faithful and that, for example, floating point errors do not greatly affect correctness and safety properties.

  9. A comparative analysis of speed profile models for wrist pointing movements.

    PubMed

    Vaisman, Lev; Dipietro, Laura; Krebs, Hermano Igo

    2013-09-01

    Following two decades of design and clinical research on robot-mediated therapy for the shoulder and elbow, therapeutic robotic devices for other joints are being proposed: several research groups including ours have designed robots for the wrist, either to be used as stand-alone devices or in conjunction with shoulder and elbow devices. However, in contrast with robots for the shoulder and elbow which were able to take advantage of descriptive kinematic models developed in neuroscience for the past 30 years, design of wrist robots controllers cannot rely on similar prior art: wrist movement kinematics has been largely unexplored. This study aimed at examining speed profiles of fast, visually evoked, visually guided, target-directed human wrist pointing movements. One thousand three-hundred ninety-eight (1398) trials were recorded from seven unimpaired subjects who performed center-out flexion/extension and abduction/adduction wrist movements and fitted with 19 models previously proposed for describing reaching speed profiles. A nonlinear, least squares optimization procedure extracted parameters' sets that minimized error between experimental and reconstructed data. Models' performances were compared based on their ability to reconstruct experimental data. Results suggest that the support-bounded lognormal is the best model for speed profiles of fast, wrist pointing movements. Applications include design of control algorithms for therapeutic wrist robots and quantitative metrics of motor recovery.

  10. The effects of systemic stress on orthodontic tooth movement.

    PubMed

    Gameiro, Gustavo Hauber; Nouer, Darcy Flávio; Pereira-Neto, Joáo Sarmento; Urtado, Marília Bertoldo; Novaes, Pedro Duarte; de Castro, Margaret; Veiga, Maria Cecília Ferraz Arruda

    2008-11-01

    To determine if systemic stress affects the biological reactions occurring during orthodontic tooth movement. Four groups of male 10 week-old Wistar rats were used. Group A animals (N=10) were restrained for one hour per day for 40 days; Group B animals (N=10) were restrained for one hour per day for three days; Group C (N=10) and Group D (N=8) animals were unrestrained. The upper left first molars in the rats in Groups A (long-term stress), B (short-term stress) and C (control) were moved mesially during the last 14 days of the experiment. The animals in Group D (N=8) were used for body weight and hormonal dosage comparisons only. They were not subjected to any stress and did not have appliances fitted. All animals were killed at 18 weeks of age and blood collected for measurement of plasma corticosterone. Tooth movement was measured with an electronic caliper. The right and left hemi-maxillae of five rats from each group were removed and the number of tartrate-resistant acid phosphatase (TRAP) positive cells, defined as osteoclasts, adjacent to the mesial roots of the upper first molars counted. The contralateral side in each animal served as the control (split-mouth design). Corticosterone levels were significantly higher in the stressed groups (Groups A and B) than in the control group (Group C). Tooth movement was significantly greater in Group A (long-term stress) compared with Group B (short-term stress) and Group C (control), which did not differ from each other. There were significantly more osteoclasts in the long-term stress group than in the short-term stress and control groups. Persistent systemic stress increases bone resorption during orthodontic tooth movement. Systemic stress may affect the rate of tooth movement during orthodontic treatment.

  11. Combinations of chromosome transfer and genome editing for the development of cell/animal models of human disease and humanized animal models.

    PubMed

    Uno, Narumi; Abe, Satoshi; Oshimura, Mitsuo; Kazuki, Yasuhiro

    2018-02-01

    Chromosome transfer technology, including chromosome modification, enables the introduction of Mb-sized or multiple genes to desired cells or animals. This technology has allowed innovative developments to be made for models of human disease and humanized animals, including Down syndrome model mice and humanized transchromosomic (Tc) immunoglobulin mice. Genome editing techniques are developing rapidly, and permit modifications such as gene knockout and knockin to be performed in various cell lines and animals. This review summarizes chromosome transfer-related technologies and the combined technologies of chromosome transfer and genome editing mainly for the production of cell/animal models of human disease and humanized animal models. Specifically, these include: (1) chromosome modification with genome editing in Chinese hamster ovary cells and mouse A9 cells for efficient transfer to desired cell types; (2) single-nucleotide polymorphism modification in humanized Tc mice with genome editing; and (3) generation of a disease model of Down syndrome-associated hematopoiesis abnormalities by the transfer of human chromosome 21 to normal human embryonic stem cells and the induction of mutation(s) in the endogenous gene(s) with genome editing. These combinations of chromosome transfer and genome editing open up new avenues for drug development and therapy as well as for basic research.

  12. An action potential-driven model of soleus muscle activation dynamics for locomotor-like movements

    NASA Astrophysics Data System (ADS)

    Kim, Hojeong; Sandercock, Thomas G.; Heckman, C. J.

    2015-08-01

    Objective. The goal of this study was to develop a physiologically plausible, computationally robust model for muscle activation dynamics (A(t)) under physiologically relevant excitation and movement. Approach. The interaction of excitation and movement on A(t) was investigated comparing the force production between a cat soleus muscle and its Hill-type model. For capturing A(t) under excitation and movement variation, a modular modeling framework was proposed comprising of three compartments: (1) spikes-to-[Ca2+]; (2) [Ca2+]-to-A; and (3) A-to-force transformation. The individual signal transformations were modeled based on physiological factors so that the parameter values could be separately determined for individual modules directly based on experimental data. Main results. The strong dependency of A(t) on excitation frequency and muscle length was found during both isometric and dynamically-moving contractions. The identified dependencies of A(t) under the static and dynamic conditions could be incorporated in the modular modeling framework by modulating the model parameters as a function of movement input. The new modeling approach was also applicable to cat soleus muscles producing waveforms independent of those used to set the model parameters. Significance. This study provides a modeling framework for spike-driven muscle responses during movement, that is suitable not only for insights into molecular mechanisms underlying muscle behaviors but also for large scale simulations.

  13. Animal Models of Diabetic Retinopathy: Summary and Comparison

    PubMed Central

    Lo, Amy C. Y.

    2013-01-01

    Diabetic retinopathy (DR) is a microvascular complication associated with chronic exposure to hyperglycemia and is a major cause of blindness worldwide. Although clinical assessment and retinal autopsy of diabetic patients provide information on the features and progression of DR, its underlying pathophysiological mechanism cannot be deduced. In order to have a better understanding of the development of DR at the molecular and cellular levels, a variety of animal models have been developed. They include pharmacological induction of hyperglycemia and spontaneous diabetic rodents as well as models of angiogenesis without diabetes (to compensate for the absence of proliferative DR symptoms). In this review, we summarize the existing protocols to induce diabetes using STZ. We also describe and compare the pathological presentations, in both morphological and functional aspects, of the currently available DR animal models. The advantages and disadvantages of using different animals, ranging from zebrafish, rodents to other higher-order mammals, are also discussed. Until now, there is no single model that displays all the clinical features of DR as seen in human. Yet, with the understanding of the pathological findings in these animal models, researchers can select the most suitable models for mechanistic studies or drug screening. PMID:24286086

  14. Animal models of obsessive–compulsive disorder: utility and limitations

    PubMed Central

    Alonso, Pino; López-Solà, Clara; Real, Eva; Segalàs, Cinto; Menchón, José Manuel

    2015-01-01

    Obsessive–compulsive disorder (OCD) is a disabling and common neuropsychiatric condition of poorly known etiology. Many attempts have been made in the last few years to develop animal models of OCD with the aim of clarifying the genetic, neurochemical, and neuroanatomical basis of the disorder, as well as of developing novel pharmacological and neurosurgical treatments that may help to improve the prognosis of the illness. The latter goal is particularly important given that around 40% of patients with OCD do not respond to currently available therapies. This article summarizes strengths and limitations of the leading animal models of OCD including genetic, pharmacologically induced, behavioral manipulation-based, and neurodevelopmental models according to their face, construct, and predictive validity. On the basis of this evaluation, we discuss that currently labeled “animal models of OCD” should be regarded not as models of OCD but, rather, as animal models of different psychopathological processes, such as compulsivity, stereotypy, or perseverance, that are present not only in OCD but also in other psychiatric or neurological disorders. Animal models might constitute a challenging approach to study the neural and genetic mechanism of these phenomena from a trans-diagnostic perspective. Animal models are also of particular interest as tools for developing new therapeutic options for OCD, with the greatest convergence focusing on the glutamatergic system, the role of ovarian and related hormones, and the exploration of new potential targets for deep brain stimulation. Finally, future research on neurocognitive deficits associated with OCD through the use of analogous animal tasks could also provide a genuine opportunity to disentangle the complex etiology of the disorder. PMID:26346234

  15. Model for the prediction of subsurface strata movement due to underground mining

    NASA Astrophysics Data System (ADS)

    Cheng, Jianwei; Liu, Fangyuan; Li, Siyuan

    2017-12-01

    The problem of ground control stability due to large underground mining operations is often associated with large movements and deformations of strata. It is a complicated problem, and can induce severe safety or environmental hazards either at the surface or in strata. Hence, knowing the subsurface strata movement characteristics, and making any subsidence predictions in advance, are desirable for mining engineers to estimate any damage likely to affect the ground surface or subsurface strata. Based on previous research findings, this paper broadly applies a surface subsidence prediction model based on the influence function method to subsurface strata, in order to predict subsurface stratum movement. A step-wise prediction model is proposed, to investigate the movement of underground strata. The model involves a dynamic iteration calculation process to derive the movements and deformations for each stratum layer; modifications to the influence method function are also made for more precise calculations. The critical subsidence parameters, incorporating stratum mechanical properties and the spatial relationship of interest at the mining level, are thoroughly considered, with the purpose of improving the reliability of input parameters. Such research efforts can be very helpful to mining engineers’ understanding of the moving behavior of all strata over underground excavations, and assist in making any damage mitigation plan. In order to check the reliability of the model, two methods are carried out and cross-validation applied. One is to use a borehole TV monitor recording to identify the progress of subsurface stratum bedding and caving in a coal mine, the other is to conduct physical modelling of the subsidence in underground strata. The results of these two methods are used to compare with theoretical results calculated by the proposed mathematical model. The testing results agree well with each other, and the acceptable accuracy and reliability of the

  16. The Effects of Exercise on Cognitive Recovery after Acquired Brain Injury in Animal Models: A Systematic Review

    PubMed Central

    Wogensen, Elise; Malá, Hana

    2015-01-01

    The objective of the present paper is to review the current status of exercise as a tool to promote cognitive rehabilitation after acquired brain injury (ABI) in animal model-based research. Searches were conducted on the PubMed, Scopus, and psycINFO databases in February 2014. Search strings used were: exercise (and) animal model (or) rodent (or) rat (and) traumatic brain injury (or) cerebral ischemia (or) brain irradiation. Studies were selected if they were (1) in English, (2) used adult animals subjected to acquired brain injury, (3) used exercise as an intervention tool after inflicted injury, (4) used exercise paradigms demanding movement of all extremities, (5) had exercise intervention effects that could be distinguished from other potential intervention effects, and (6) contained at least one measure of cognitive and/or emotional function. Out of 2308 hits, 22 publications fulfilled the criteria. The studies were examined relative to cognitive effects associated with three themes: exercise type (forced or voluntary), timing of exercise (early or late), and dose-related factors (intensity, duration, etc.). The studies indicate that exercise in many cases can promote cognitive recovery after brain injury. However, the optimal parameters to ensure cognitive rehabilitation efficacy still elude us, due to considerable methodological variations between studies. PMID:26509085

  17. On the origin of bursts and heavy tails in animal dynamics

    NASA Astrophysics Data System (ADS)

    Reynolds, A. M.

    2011-01-01

    Over recent years there has been an accumulation of evidence that many animal behaviours are characterised by common scale-invariant patterns of switching between two contrasting activities over a period of time. This is evidenced in mammalian wake-sleep patterns, in the intermittent stop-start locomotion of Drosophila fruit flies, and in the Lévy walk movement patterns of a diverse range of animals in which straight-line movements are punctuated by occasional turns. Here it is shown that these dynamics can be modelled by a stochastic variant of Barabási’s model [A.-L. Barabási, The origin of bursts and heavy tails in human dynamics, Nature 435 (2005) 207-211] for bursts and heavy tails in human dynamics. The new model captures a tension between two competing and conflicting activities. The durations of one type of activity are distributed according to an inverse-square power-law, mirroring the ubiquity of inverse-square power-law scaling seen in empirical data. The durations of the second type of activity follow exponential distributions with characteristic timescales that depend on species and metabolic rates. This again is a common feature of animal behaviour. Bursty human dynamics, on the other hand, are characterised by power-law distributions with scaling exponents close to -1 and -3/2.

  18. Learning to See: Guiding Students' Attention via a Model's Eye Movements Fosters Learning

    ERIC Educational Resources Information Center

    Jarodzka, Halszka; van Gog, Tamara; Dorr, Michael; Scheiter, Katharina; Gerjets, Peter

    2013-01-01

    This study investigated how to teach perceptual tasks, that is, classifying fish locomotion, through eye movement modeling examples (EMME). EMME consisted of a replay of eye movements of a didactically behaving domain expert (model), which had been recorded while he executed the task, superimposed onto the video stimulus. Seventy-five students…

  19. Overturning conclusions of Lévy flight movement patterns by fishing boats and foraging animals.

    PubMed

    Edwards, Andrew M

    2011-06-01

    A surprisingly diverse variety of foragers have previously been concluded to exhibit movement patterns known as Lévy flights, a special type of random walk. These foragers range in size from microzooplankton in experiments to fishermen in the Pacific Ocean and the North Sea. The Lévy flight conclusion implies that all the foragers have similar scale-free movement patterns that can be described by a single dimensionless parameter, the exponent micro of a power-law (Pareto) distribution. However, the previous conclusions have been made using methods that have since been shown to be problematic: inaccurate techniques were used to estimate micro, and the power-law distribution was usually assumed to hold without testing any alternative hypotheses. Therefore, I address the open question of whether the previous data still support the Lévy flight hypothesis, and thus determine whether Lévy flights really are so ubiquitous in ecology. I present a comprehensive reanalysis of 17 data sets from seven previous studies for which Lévy flight behavior had been concluded, covering marine, terrestrial, and experimental systems from four continents. I use the modern likelihood and Akaike weights approach to test whether simple alternative models are more supported by the data than Lévy flights. The previously estimated values of the power-law exponent micro do not match those calculated here using the accurate likelihood approach, and almost all of them lie outside of the likelihood-based 95% confidence intervals. Furthermore, the original power-law Lévy flight model is overwhelmingly rejected for 16 out of the 17 data sets when tested against three other simple models. For one data set, the data are consistent with coming from a bounded power-law distribution (a truncated Lévy flight). For three other data sets, an exponential distribution corresponding to a simple Poisson process is suitable. Thus, Lévy flight movement patterns are not the common phenomena that was once

  20. Real Time 3D Facial Movement Tracking Using a Monocular Camera

    PubMed Central

    Dong, Yanchao; Wang, Yanming; Yue, Jiguang; Hu, Zhencheng

    2016-01-01

    The paper proposes a robust framework for 3D facial movement tracking in real time using a monocular camera. It is designed to estimate the 3D face pose and local facial animation such as eyelid movement and mouth movement. The framework firstly utilizes the Discriminative Shape Regression method to locate the facial feature points on the 2D image and fuses the 2D data with a 3D face model using Extended Kalman Filter to yield 3D facial movement information. An alternating optimizing strategy is adopted to fit to different persons automatically. Experiments show that the proposed framework could track the 3D facial movement across various poses and illumination conditions. Given the real face scale the framework could track the eyelid with an error of 1 mm and mouth with an error of 2 mm. The tracking result is reliable for expression analysis or mental state inference. PMID:27463714

  1. Contemporary Animal Models For Human Gene Therapy Applications.

    PubMed

    Gopinath, Chitra; Nathar, Trupti Job; Ghosh, Arkasubhra; Hickstein, Dennis Durand; Nelson, Everette Jacob Remington

    2015-01-01

    Over the past three decades, gene therapy has been making considerable progress as an alternative strategy in the treatment of many diseases. Since 2009, several studies have been reported in humans on the successful treatment of various diseases. Animal models mimicking human disease conditions are very essential at the preclinical stage before embarking on a clinical trial. In gene therapy, for instance, they are useful in the assessment of variables related to the use of viral vectors such as safety, efficacy, dosage and localization of transgene expression. However, choosing a suitable disease-specific model is of paramount importance for successful clinical translation. This review focuses on the animal models that are most commonly used in gene therapy studies, such as murine, canine, non-human primates, rabbits, porcine, and a more recently developed humanized mice. Though small and large animals both have their own pros and cons as disease-specific models, the choice is made largely based on the type and length of study performed. While small animals with a shorter life span could be well-suited for degenerative/aging studies, large animals with longer life span could suit longitudinal studies and also help with dosage adjustments to maximize therapeutic benefit. Recently, humanized mice or mouse-human chimaeras have gained interest in the study of human tissues or cells, thereby providing a more reliable understanding of therapeutic interventions. Thus, animal models are of great importance with regard to testing new vector technologies in vivo for assessing safety and efficacy prior to a gene therapy clinical trial.

  2. A systematic review of animal models for Staphylococcus aureus osteomyelitis

    PubMed Central

    Reizner, W.; Hunter, J.G.; O’Malley, N.T.; Southgate, R.D.; Schwarz, E.M.; Kates, S.L.

    2015-01-01

    Staphylococcus aureus (S. aureus) osteomyelitis is a significant complication for orthopaedic patients undergoing surgery, particularly with fracture fixation and arthroplasty. Given the difficulty in studying S. aureus infections in human subjects, animal models serve an integral role in exploring the pathogenesis of osteomyelitis, and aid in determining the efficacy of prophylactic and therapeutic treatments. Animal models should mimic the clinical scenarios seen in patients as closely as possible to permit the experimental results to be translated to the corresponding clinical care. To help understand existing animal models of S. aureus, we conducted a systematic search of PubMed & Ovid MEDLINE to identify in vivo animal experiments that have investigated the management of S. aureus osteomyelitis in the context of fractures and metallic implants. In this review, experimental studies are categorized by animal species and are further classified by the setting of the infection. Study methods are summarized and the relevant advantages and disadvantages of each species and model are discussed. While no ideal animal model exists, the understanding of a model’s strengths and limitations should assist clinicians and researchers to appropriately select an animal model to translate the conclusions to the clinical setting. PMID:24668594

  3. Effect of supplementary zinc on orthodontic tooth movement in a rat model

    PubMed Central

    Sadegh, Ahmad Akhoundi Mohammad; Rezvaneh, Ghazanfari; Shahroo, Etemad-Moghadam; Mojgan, Alaeddini; Azam, Khorshidian; Shahram, Rabbani; Reza, Shamshiri Ahmad; Nafiseh, Momeni

    2016-01-01

    ABSTRACT Introduction: Osteoclasts and osteoblasts are responsible for regulating bone homeostasis during which the trace element zinc has been shown to exert a cumulative effect on bone mass by stimulating osteoblastic bone formation and inhibiting osteoclastic bone resorption. Objective: The aim of the present study was to investigate the effects of zinc (Zn) on orthodontic tooth movement (OTM) in a rat model. Material and Methods: A total of 44 male Wistar rats were divided into four groups of 11 animals each and received 0, 1.5, 20 and 50 ppm Zn in distilled water for 60 days. In the last 21 days of the study, nickel-titanium closed coil springs were ligated between maxillary right incisors and first molars of all rats, and tooth movement was measured at the end of this period. Histological analysis of hematoxylin/eosin slides was performed to assess root resorption lacunae, osteoclast number and periodontal ligament (PDL) width. Results: Mean OTM was calculated as 51.8, 49.1, 35.5 and 45 µm in the 0, 1.5, 20 and 50 ppm zinc-receiving groups, respectively. There were no significant differences in neither OTM nor histological parameters among the study groups (p > 0.05). Conclusion: According to the results obtained in the current investigation, increase in supplementary zinc up to 50 ppm does not affect the rate of OTM neither bone and root resorption in rats. PMID:27275614

  4. Chest compressions in newborn animal models: A review.

    PubMed

    Solevåg, Anne Lee; Cheung, Po-Yin; Lie, Helene; O'Reilly, Megan; Aziz, Khalid; Nakstad, Britt; Schmölzer, Georg Marcus

    2015-11-01

    Much of the knowledge about the optimal way to perform chest compressions (CC) in newborn infants is derived from animal studies. The objective of this review was to identify studies of CC in newborn term animal models and review the evidence. We also provide an overview of the different models. MEDLINE, EMBASE and CINAHL, until September 29th 2014. Study eligibility criteria and interventions: term newborn animal models where CC was performed. Based on 419 retrieved studies from MEDLINE and 502 from EMBASE, 28 studies were included. No additional studies were identified in CINAHL. Most of the studies were performed in pigs after perinatal transition without long-term follow-up. The models differed widely in methodological aspects, which limits the possibility to compare and synthesize findings. Studies uncommonly reported the method for randomization and allocation concealment, and a limited number were blinded. Only the evidence in favour of the two-thumb encircling hands technique for performing CC, a CC to ventilation ratio of 3:1; and that air can be used for ventilation during CC; was supported by more than one study. Animal studies should be performed and reported with the same rigor as in human randomized trials. Good transitional and survival models are needed to further increase the strength of the evidence derived from animal studies of newborn chest compressions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Animal models of GM2 gangliosidosis: utility and limitations.

    PubMed

    Lawson, Cheryl A; Martin, Douglas R

    2016-01-01

    GM2 gangliosidosis, a subset of lysosomal storage disorders, is caused by a deficiency of the glycohydrolase, β-N-acetylhexosaminidase, and includes the closely related Tay-Sachs and Sandhoff diseases. The enzyme deficiency prevents the normal, stepwise degradation of ganglioside, which accumulates unchecked within the cellular lysosome, particularly in neurons. As a result, individuals with GM2 gangliosidosis experience progressive neurological diseases including motor deficits, progressive weakness and hypotonia, decreased responsiveness, vision deterioration, and seizures. Mice and cats are well-established animal models for Sandhoff disease, whereas Jacob sheep are the only known laboratory animal model of Tay-Sachs disease to exhibit clinical symptoms. Since the human diseases are relatively rare, animal models are indispensable tools for further study of pathogenesis and for development of potential treatments. Though no effective treatments for gangliosidoses currently exist, animal models have been used to test promising experimental therapies. Herein, the utility and limitations of gangliosidosis animal models and how they have contributed to the development of potential new treatments are described.

  6. Animal models of GM2 gangliosidosis: utility and limitations

    PubMed Central

    Lawson, Cheryl A; Martin, Douglas R

    2016-01-01

    GM2 gangliosidosis, a subset of lysosomal storage disorders, is caused by a deficiency of the glycohydrolase, β-N-acetylhexosaminidase, and includes the closely related Tay–Sachs and Sandhoff diseases. The enzyme deficiency prevents the normal, stepwise degradation of ganglioside, which accumulates unchecked within the cellular lysosome, particularly in neurons. As a result, individuals with GM2 gangliosidosis experience progressive neurological diseases including motor deficits, progressive weakness and hypotonia, decreased responsiveness, vision deterioration, and seizures. Mice and cats are well-established animal models for Sandhoff disease, whereas Jacob sheep are the only known laboratory animal model of Tay–Sachs disease to exhibit clinical symptoms. Since the human diseases are relatively rare, animal models are indispensable tools for further study of pathogenesis and for development of potential treatments. Though no effective treatments for gangliosidoses currently exist, animal models have been used to test promising experimental therapies. Herein, the utility and limitations of gangliosidosis animal models and how they have contributed to the development of potential new treatments are described. PMID:27499644

  7. Developing Educational Computer Animation Based on Human Personality Types

    ERIC Educational Resources Information Center

    Musa, Sajid; Ziatdinov, Rushan; Sozcu, Omer Faruk; Griffiths, Carol

    2015-01-01

    Computer animation in the past decade has become one of the most noticeable features of technology-based learning environments. By its definition, it refers to simulated motion pictures showing movement of drawn objects, and is often defined as the art in movement. Its educational application known as educational computer animation is considered…

  8. Modeling potential movements of the emerald ash borer: the model framework

    Treesearch

    Louis R. Iverson; Anantha Prasad; Jonathan Bossenbroek; Davis Sydnor; Mark W. Schwartz

    2010-01-01

    The emerald ash borer (EAB, Agrilus planipennis Fairmaire) is threatening to decimate native ashes (Fraxinus spp.) across North America and, so far, has devastated ash populations across sections of Michigan, Ohio, Indiana, and Ontario. We are attempting to develop a computer model that will predict EAB future movement by adapting...

  9. Animal models of chronic obstructive pulmonary disease.

    PubMed

    Pérez-Rial, Sandra; Girón-Martínez, Álvaro; Peces-Barba, Germán

    2015-03-01

    Animal models of disease have always been welcomed by the scientific community because they provide an approach to the investigation of certain aspects of the disease in question. Animal models of COPD cannot reproduce the heterogeneity of the disease and usually only manage to represent the disease in its milder stages. Moreover, airflow obstruction, the variable that determines patient diagnosis, not always taken into account in the models. For this reason, models have focused on the development of emphysema, easily detectable by lung morphometry, and have disregarded other components of the disease, such as airway injury or associated vascular changes. Continuous, long-term exposure to cigarette smoke is considered the main risk factor for this disease, justifying the fact that the cigarette smoke exposure model is the most widely used. Some variations on this basic model, related to exposure time, the association of other inducers or inhibitors, exacerbations or the use of transgenic animals to facilitate the identification of pathogenic pathways have been developed. Some variations or heterogeneity of this disease, then, can be reproduced and models can be designed for resolving researchers' questions on disease identification or treatment responses. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  10. Computer modeling and simulation of human movement. Applications in sport and rehabilitation.

    PubMed

    Neptune, R R

    2000-05-01

    Computer modeling and simulation of human movement plays an increasingly important role in sport and rehabilitation, with applications ranging from sport equipment design to understanding pathologic gait. The complex dynamic interactions within the musculoskeletal and neuromuscular systems make analyzing human movement with existing experimental techniques difficult but computer modeling and simulation allows for the identification of these complex interactions and causal relationships between input and output variables. This article provides an overview of computer modeling and simulation and presents an example application in the field of rehabilitation.

  11. Animal models for periodontal regeneration and peri-implant responses.

    PubMed

    Kantarci, Alpdogan; Hasturk, Hatice; Van Dyke, Thomas E

    2015-06-01

    Translation of experimental data to the clinical setting requires the safety and efficacy of such data to be confirmed in animal systems before application in humans. In dental research, the animal species used is dependent largely on the research question or on the disease model. Periodontal disease and, by analogy, peri-implant disease, are complex infections that result in a tissue-degrading inflammatory response. It is impossible to explore the complex pathogenesis of periodontitis or peri-implantitis using only reductionist in-vitro methods. Both the disease process and healing of the periodontal and peri-implant tissues can be studied in animals. Regeneration (after periodontal surgery), in response to various biologic materials with potential for tissue engineering, is a continuous process involving various types of tissue, including epithelia, connective tissues and alveolar bone. The same principles apply to peri-implant healing. Given the complexity of the biology, animal models are necessary and serve as the standard for successful translation of regenerative materials and dental implants to the clinical setting. Smaller species of animal are more convenient for disease-associated research, whereas larger animals are more appropriate for studies that target tissue healing as the anatomy of larger animals more closely resembles human dento-alveolar architecture. This review focuses on the animal models available for the study of regeneration in periodontal research and implantology; the advantages and disadvantages of each animal model; the interpretation of data acquired; and future perspectives of animal research, with a discussion of possible nonanimal alternatives. Power calculations in such studies are crucial in order to use a sample size that is large enough to generate statistically useful data, whilst, at the same time, small enough to prevent the unnecessary use of animals. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. 9 CFR 82.8 - Interstate movement of eggs, other than hatching eggs, from a quarantined area.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement of eggs, other than hatching eggs, from a quarantined area. 82.8 Section 82.8 Animals and Animal Products ANIMAL AND... Disease (END) § 82.8 Interstate movement of eggs, other than hatching eggs, from a quarantined area. (a...

  13. 9 CFR 82.8 - Interstate movement of eggs, other than hatching eggs, from a quarantined area.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Interstate movement of eggs, other than hatching eggs, from a quarantined area. 82.8 Section 82.8 Animals and Animal Products ANIMAL AND... Disease (END) § 82.8 Interstate movement of eggs, other than hatching eggs, from a quarantined area. (a...

  14. 9 CFR 118.3 - Movement of detained biological products; Termination of detention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Movement of detained biological... VECTORS DETENTION; SEIZURE AND CONDEMNATION § 118.3 Movement of detained biological products; Termination of detention. Except as provided in paragraphs (a) and (b) of this section, no biological product...

  15. Overview of large animal myocardial infarction models (review).

    PubMed

    Lukács, E; Magyari, B; Tóth, L; Petrási, Zs; Repa, I; Koller, A; Horváth, Iván

    2012-12-01

    There are several experimental models for the in vivo investigation of myocardial infarction (MI) in small (mouse, rat) and large animals (dog, pig, sheep and baboons). The application of large animal models raises ethical concerns, the design of experiments needs longer follow-up times, requiring proper breeding and housing conditions, therefore resulting in higher cost, than in vitro or small animal studies. On the other hand, the relevance of large animal models is very important, since they mostly resemble to human physiological and pathophysiological processes. The first main difference among MI models is the method of induction (open or closed chest, e.g. surgical or catheter based); the second main difference is the presence or absence of reperfusion. The former (i.e. reperfused MI) allows the investigation of reperfusion injury and new catheter based techniques during percutaneous coronary interventions, while the latter (i.e. nonreperfused MI) serves as a traditional coronary occlusion model, to test the effects of new pharmacological agents and biological therapies, as cell therapy. The reperfused and nonreperfused myocardial infarction has different outcomes, regarding left ventricular function, remodelling, subsequent heart failure, aneurysm formation and mortality. Our aim was to review the literature and report our findings regarding experimental MI models, regarding the differences among species, methods, reproducibility and interpretation.

  16. Combining High-Speed Cameras and Stop-Motion Animation Software to Support Students' Modeling of Human Body Movement

    ERIC Educational Resources Information Center

    Lee, Victor R.

    2015-01-01

    Biomechanics, and specifically the biomechanics associated with human movement, is a potentially rich backdrop against which educators can design innovative science teaching and learning activities. Moreover, the use of technologies associated with biomechanics research, such as high-speed cameras that can produce high-quality slow-motion video,…

  17. Bivariate Gaussian bridges: directional factorization of diffusion in Brownian bridge models.

    PubMed

    Kranstauber, Bart; Safi, Kamran; Bartumeus, Frederic

    2014-01-01

    In recent years high resolution animal tracking data has become the standard in movement ecology. The Brownian Bridge Movement Model (BBMM) is a widely adopted approach to describe animal space use from such high resolution tracks. One of the underlying assumptions of the BBMM is isotropic diffusive motion between consecutive locations, i.e. invariant with respect to the direction. Here we propose to relax this often unrealistic assumption by separating the Brownian motion variance into two directional components, one parallel and one orthogonal to the direction of the motion. Our new model, the Bivariate Gaussian bridge (BGB), tracks movement heterogeneity across time. Using the BGB and identifying directed and non-directed movement within a trajectory resulted in more accurate utilisation distributions compared to dynamic Brownian bridges, especially for trajectories with a non-isotropic diffusion, such as directed movement or Lévy like movements. We evaluated our model with simulated trajectories and observed tracks, demonstrating that the improvement of our model scales with the directional correlation of a correlated random walk. We find that many of the animal trajectories do not adhere to the assumptions of the BBMM. The proposed model improves accuracy when describing the space use both in simulated correlated random walks as well as observed animal tracks. Our novel approach is implemented and available within the "move" package for R.

  18. Models for the effects of host movement in vector-borne disease systems.

    PubMed

    Cosner, Chris

    2015-12-01

    Host and/or vector movement patterns have been shown to have significant effects in both empirical studies and mathematical models of vector-borne diseases. The processes of economic development and globalization seem likely to make host movement even more important in the future. This article is a brief survey of some of the approaches that have been used to study the effects of host movement in analytic mathematical models for vector-borne diseases. It describes the formulation and interpretation of various types of spatial models and describes a few of the conclusions that can be drawn from them. It is not intended to be comprehensive but rather to provide sufficient background material and references to the literature to serve as an entry point into this area of research for interested readers. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Animated Randomness, Avatars, Movement, and Personalization in Risk Graphics

    PubMed Central

    Fuhrel-Forbis, Andrea; Wijeysundera, Harindra C; Exe, Nicole; Dickson, Mark; Holtzman, Lisa; Kahn, Valerie C; Zikmund-Fisher, Brian J

    2014-01-01

    Background Risk communication involves conveying two inherently difficult concepts about the nature of risk: the underlying random distribution of outcomes and how a population-based proportion applies to an individual. Objective The objective of this study was to test whether 4 design factors in icon arrays—animated random dispersal of risk events, avatars to represent an individual, personalization (operationalized as choosing the avatar’s color), and a moving avatar—might help convey randomness and how a given risk applies to an individual, thereby better aligning risk perceptions with risk estimates. Methods A diverse sample of 3630 adults with no previous heart disease or stroke completed an online nested factorial experiment in which they entered personal health data into a risk calculator that estimated 10-year risk of cardiovascular disease based on a robust and validated model. We randomly assigned them to view their results in 1 of 10 risk graphics that used different combinations of the 4 design factors. We measured participants’ risk perceptions as our primary outcome, as well as behavioral intentions and recall of the risk estimate. We also assessed subjective numeracy, whether or not participants knew anyone who had died of cardiovascular causes, and whether or not they knew their blood pressure and cholesterol as potential moderators. Results Animated randomness was associated with better alignment between risk estimates and risk perceptions (F 1,3576=6.12, P=.01); however, it also led to lower scores on healthy lifestyle intentions (F 1,3572=11.1, P<.001). Using an avatar increased risk perceptions overall (F 1,3576=4.61, P=.03) and most significantly increased risk perceptions among those who did not know a particular person who had experienced the grave outcomes of cardiovascular disease (F 1,3576=5.88, P=.02). Using an avatar also better aligned actual risk estimates with intentions to see a doctor (F 1,3556=6.38, P=.01). No design

  20. The movement ecology of seagrasses

    PubMed Central

    McMahon, Kathryn; van Dijk, Kor-jent; Ruiz-Montoya, Leonardo; Kendrick, Gary A.; Krauss, Siegfried L.; Waycott, Michelle; Verduin, Jennifer; Lowe, Ryan; Statton, John; Brown, Eloise; Duarte, Carlos

    2014-01-01

    A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and demographic connectivity over multiple timeframes is the novel feature of the movement ecology of seagrasses with significant evolutionary and ecological consequences. The space–time movement footprint of different life-history stages varies. For example, the distance moved by reproductive propagules and vegetative expansion via clonal growth is similar, but the timescales range exponentially, from hours to months or centuries to millennia, respectively. Consequently, environmental factors and key traits that interact to influence movement also operate on vastly different spatial and temporal scales. Six key future research areas have been identified. PMID:25297859

  1. Comparative biology of cystic fibrosis animal models.

    PubMed

    Fisher, John T; Zhang, Yulong; Engelhardt, John F

    2011-01-01

    Animal models of human diseases are critical for dissecting mechanisms of pathophysiology and developing therapies. In the context of cystic fibrosis (CF), mouse models have been the dominant species by which to study CF disease processes in vivo for the past two decades. Although much has been learned through these CF mouse models, limitations in the ability of this species to recapitulate spontaneous lung disease and several other organ abnormalities seen in CF humans have created a need for additional species on which to study CF. To this end, pig and ferret CF models have been generated by somatic cell nuclear transfer and are currently being characterized. These new larger animal models have phenotypes that appear to closely resemble human CF disease seen in newborns, and efforts to characterize their adult phenotypes are ongoing. This chapter will review current knowledge about comparative lung cell biology and cystic fibrosis transmembrane conductance regulator (CFTR) biology among mice, pigs, and ferrets that has implications for CF disease modeling in these species. We will focus on methods used to compare the biology and function of CFTR between these species and their relevance to phenotypes seen in the animal models. These cross-species comparisons and the development of both the pig and the ferret CF models may help elucidate pathophysiologic mechanisms of CF lung disease and lead to new therapeutic approaches.

  2. Real-time speech-driven animation of expressive talking faces

    NASA Astrophysics Data System (ADS)

    Liu, Jia; You, Mingyu; Chen, Chun; Song, Mingli

    2011-05-01

    In this paper, we present a real-time facial animation system in which speech drives mouth movements and facial expressions synchronously. Considering five basic emotions, a hierarchical structure with an upper layer of emotion classification is established. Based on the recognized emotion label, the under-layer classification at sub-phonemic level has been modelled on the relationship between acoustic features of frames and audio labels in phonemes. Using certain constraint, the predicted emotion labels of speech are adjusted to gain the facial expression labels which are combined with sub-phonemic labels. The combinations are mapped into facial action units (FAUs), and audio-visual synchronized animation with mouth movements and facial expressions is generated by morphing between FAUs. The experimental results demonstrate that the two-layer structure succeeds in both emotion and sub-phonemic classifications, and the synthesized facial sequences reach a comparative convincing quality.

  3. 9 CFR 82.6 - Interstate movement of dead birds and dead poultry from a quarantined area.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Interstate movement of dead birds and dead poultry from a quarantined area. 82.6 Section 82.6 Animals and Animal Products ANIMAL AND PLANT... (END) § 82.6 Interstate movement of dead birds and dead poultry from a quarantined area. (a) Except as...

  4. 9 CFR 82.6 - Interstate movement of dead birds and dead poultry from a quarantined area.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Interstate movement of dead birds and dead poultry from a quarantined area. 82.6 Section 82.6 Animals and Animal Products ANIMAL AND PLANT... movement of dead birds and dead poultry from a quarantined area. (a) Except as provided in paragraph (b) of...

  5. 9 CFR 82.6 - Interstate movement of dead birds and dead poultry from a quarantined area.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Interstate movement of dead birds and dead poultry from a quarantined area. 82.6 Section 82.6 Animals and Animal Products ANIMAL AND PLANT... (END) § 82.6 Interstate movement of dead birds and dead poultry from a quarantined area. (a) Except as...

  6. 9 CFR 72.7 - Interstate movement of cattle from cooperating States.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Interstate movement of cattle from cooperating States. 72.7 Section 72.7 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BOVINE...

  7. Development of Foundational Movement Skills: A Conceptual Model for Physical Activity Across the Lifespan.

    PubMed

    Hulteen, Ryan M; Morgan, Philip J; Barnett, Lisa M; Stodden, David F; Lubans, David R

    2018-03-09

    Evidence supports a positive association between competence in fundamental movement skills (e.g., kicking, jumping) and physical activity in young people. Whilst important, fundamental movement skills do not reflect the broad diversity of skills utilized in physical activity pursuits across the lifespan. Debate surrounds the question of what are the most salient skills to be learned which facilitate physical activity participation across the lifespan. In this paper, it is proposed that the term 'fundamental movement skills' be replaced with 'foundational movement skills'. The term 'foundational movement skills' better reflects the broad range of movement forms that increase in complexity and specificity and can be applied in a variety of settings. Thus, 'foundational movement skills' includes both traditionally conceptualized 'fundamental' movement skills and other skills (e.g., bodyweight squat, cycling, swimming strokes) that support physical activity engagement across the lifespan. A proposed conceptual model outlines how foundational movement skill competency can provide a direct or indirect pathway, via specialized movement skills, to a lifetime of physical activity. Foundational movement skill development is hypothesized to vary according to culture and/or geographical location. Further, skill development may be hindered or enhanced by physical (i.e., fitness, weight status) and psychological (i.e., perceived competence, self-efficacy) attributes. This conceptual model may advance the application of motor development principles within the public health domain. Additionally, it promotes the continued development of human movement in the context of how it leads to skillful performance and how movement skill development supports and maintains a lifetime of physical activity engagement.

  8. An equilibrium-point model of electromyographic patterns during single-joint movements based on experimentally reconstructed control signals.

    PubMed

    Latash, M L; Goodman, S R

    1994-01-01

    The purpose of this work has been to develop a model of electromyographic (EMG) patterns during single-joint movements based on a version of the equilibrium-point hypothesis, a method for experimental reconstruction of the joint compliant characteristics, the dual-strategy hypothesis, and a kinematic model of movement trajectory. EMG patterns are considered emergent properties of hypothetical control patterns that are equally affected by the control signals and peripheral feedback reflecting actual movement trajectory. A computer model generated the EMG patterns based on simulated movement kinematics and hypothetical control signals derived from the reconstructed joint compliant characteristics. The model predictions have been compared to published recordings of movement kinematics and EMG patterns in a variety of movement conditions, including movements over different distances, at different speeds, against different-known inertial loads, and in conditions of possible unexpected decrease in the inertial load. Changes in task parameters within the model led to simulated EMG patterns qualitatively similar to the experimentally recorded EMG patterns. The model's predictive power compares it favourably to the existing models of the EMG patterns. Copyright © 1994. Published by Elsevier Ltd.

  9. Free boundary models for mosquito range movement driven by climate warming.

    PubMed

    Bao, Wendi; Du, Yihong; Lin, Zhigui; Zhu, Huaiping

    2018-03-01

    As vectors, mosquitoes transmit numerous mosquito-borne diseases. Among the many factors affecting the distribution and density of mosquitoes, climate change and warming have been increasingly recognized as major ones. In this paper, we make use of three diffusive logistic models with free boundary in one space dimension to explore the impact of climate warming on the movement of mosquito range. First, a general model incorporating temperature change with location and time is introduced. In order to gain insights of the model, a simplified version of the model with the change of temperature depending only on location is analyzed theoretically, for which the dynamical behavior is completely determined and presented. The general model can be modified into a more realistic one of seasonal succession type, to take into account of the seasonal changes of mosquito movements during each year, where the general model applies only for the time period of the warm seasons of the year, and during the cold season, the mosquito range is fixed and the population is assumed to be in a hibernating status. For both the general model and the seasonal succession model, our numerical simulations indicate that the long-time dynamical behavior is qualitatively similar to the simplified model, and the effect of climate warming on the movement of mosquitoes can be easily captured. Moreover, our analysis reveals that hibernating enhances the chances of survival and successful spreading of the mosquitoes, but it slows down the spreading speed.

  10. How animal models inform child and adolescent psychiatry.

    PubMed

    Stevens, Hanna E; Vaccarino, Flora M

    2015-05-01

    Every available approach should be used to advance the field of child and adolescent psychiatry. Biological systems are important for the behavioral problems of children. Close examination of nonhuman animals and the biology and behavior that they share with humans is an approach that must be used to advance the clinical work of child psychiatry. We review here how model systems are used to contribute to significant insights into childhood psychiatric disorders. Model systems have not only demonstrated causality of risk factors for psychiatric pathophysiology, but have also allowed child psychiatrists to think in different ways about risks for psychiatric disorders and multiple levels that might be the basis of recovery and prevention. We present examples of how animal systems are used to benefit child psychiatry, including through environmental, genetic, and acute biological manipulations. Animal model work has been essential in our current thinking about childhood disorders, including the importance of dose and timing of risk factors, specific features of risk factors that are significant, neurochemistry involved in brain functioning, molecular components of brain development, and the importance of cellular processes previously neglected in psychiatric theories. Animal models have clear advantages and disadvantages that must be considered for these systems to be useful. Coupled with increasingly sophisticated methods for investigating human behavior and biology, animal model systems will continue to make essential contributions to our field. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  11. How Animal Models Inform Child and Adolescent Psychiatry

    PubMed Central

    Stevens, Hanna E.; Vaccarino, Flora M.

    2015-01-01

    Objective Every available approach should be utilized to advance the field of child and adolescent psychiatry. Biological systems are important for the behavioral problems of children. Close examination of non-human animals and the biology and behavior they share with humans is an approach that must be used to advance the clinical work of child psychiatry. Method We review here how model systems are used to contribute to significant insights into childhood psychiatric disorders. Model systems have not only demonstrated causality of risk factors for psychiatric pathophysiology but have also allowed child psychiatrists to think in different ways about risks for psychiatric disorders and multiple levels that might be the basis of recovery and prevention. Results We present examples of how animal systems are utilized to benefit child psychiatry, including through environmental, genetic, and acute biological manipulations. Animal model work has been essential in our current thinking about childhood disorders, including the importance of dose and timing of risk factors, specific features of risk factors that are significant, neurochemistry involved in brain functioning, molecular components of brain development, and the importance of cellular processes previously neglected in psychiatric theories. Conclusion Animal models have clear advantages and disadvantages that must both be considered for these systems to be useful. Coupled with increasingly sophisticated methods for investigating human behavior and biology, animal model systems will continue to make essential contributions to our field. PMID:25901771

  12. Animal models of viral hemorrhagic fever.

    PubMed

    Smith, Darci R; Holbrook, Michael R; Gowen, Brian B

    2014-12-01

    The term "viral hemorrhagic fever" (VHF) designates a syndrome of acute febrile illness, increased vascular permeability and coagulation defects which often progresses to bleeding and shock and may be fatal in a significant percentage of cases. The causative agents are some 20 different RNA viruses in the families Arenaviridae, Bunyaviridae, Filoviridae and Flaviviridae, which are maintained in a variety of animal species and are transferred to humans through direct or indirect contact or by an arthropod vector. Except for dengue, which is transmitted among humans by mosquitoes, the geographic distribution of each type of VHF is determined by the range of its animal reservoir. Treatments are available for Argentine HF and Lassa fever, but no approved countermeasures have been developed against other types of VHF. The development of effective interventions is hindered by the sporadic nature of most infections and their occurrence in geographic regions with limited medical resources. Laboratory animal models that faithfully reproduce human disease are therefore essential for the evaluation of potential vaccines and therapeutics. The goal of this review is to highlight the current status of animal models that can be used to study the pathogenesis of VHF and test new countermeasures. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Examining speed versus selection in connectivity models using elk migration as an example

    USGS Publications Warehouse

    Brennan, Angela; Hanks, Ephraim M.; Merkle, Jerod A.; Cole, Eric K.; Dewey, Sarah R.; Courtemanch, Alyson B.; Cross, Paul C.

    2018-01-01

    ContextLandscape resistance is vital to connectivity modeling and frequently derived from resource selection functions (RSFs). RSFs estimate relative probability of use and tend to focus on understanding habitat preferences during slow, routine animal movements (e.g., foraging). Dispersal and migration, however, can produce rarer, faster movements, in which case models of movement speed rather than resource selection may be more realistic for identifying habitats that facilitate connectivity.ObjectiveTo compare two connectivity modeling approaches applied to resistance estimated from models of movement rate and resource selection.MethodsUsing movement data from migrating elk, we evaluated continuous time Markov chain (CTMC) and movement-based RSF models (i.e., step selection functions [SSFs]). We applied circuit theory and shortest random path (SRP) algorithms to CTMC, SSF and null (i.e., flat) resistance surfaces to predict corridors between elk seasonal ranges. We evaluated prediction accuracy by comparing model predictions to empirical elk movements.ResultsAll connectivity models predicted elk movements well, but models applied to CTMC resistance were more accurate than models applied to SSF and null resistance. Circuit theory models were more accurate on average than SRP models.ConclusionsCTMC can be more realistic than SSFs for estimating resistance for fast movements, though SSFs may demonstrate some predictive ability when animals also move slowly through corridors (e.g., stopover use during migration). High null model accuracy suggests seasonal range data may also be critical for predicting direct migration routes. For animals that migrate or disperse across large landscapes, we recommend incorporating CTMC into the connectivity modeling toolkit.

  14. Movements of four native Hawaiian birds across a naturally fragmented landscape

    Treesearch

    Jessie L. Knowlton; David J. Flaspohler; Eben H. Paxton; Tadashi Fukami; Christian P. Giardina; Daniel S. Gruner; Erin E. Wilson Rankin

    2017-01-01

    Animals often increase their fitness by moving across space in response to temporal variation in habitat quality and resource availability, and as a result of intra and inter-specific interactions. The long-term persistence of populations and even whole species depends on the collective patterns of individual movements, yet animal movements have been poorly studied at...

  15. Three-dimensional reconstructions come to life--interactive 3D PDF animations in functional morphology.

    PubMed

    van de Kamp, Thomas; dos Santos Rolo, Tomy; Vagovič, Patrik; Baumbach, Tilo; Riedel, Alexander

    2014-01-01

    Digital surface mesh models based on segmented datasets have become an integral part of studies on animal anatomy and functional morphology; usually, they are published as static images, movies or as interactive PDF files. We demonstrate the use of animated 3D models embedded in PDF documents, which combine the advantages of both movie and interactivity, based on the example of preserved Trigonopterus weevils. The method is particularly suitable to simulate joints with largely deterministic movements due to precise form closure. We illustrate the function of an individual screw-and-nut type hip joint and proceed to the complex movements of the entire insect attaining a defence position. This posture is achieved by a specific cascade of movements: Head and legs interlock mutually and with specific features of thorax and the first abdominal ventrite, presumably to increase the mechanical stability of the beetle and to maintain the defence position with minimal muscle activity. The deterministic interaction of accurately fitting body parts follows a defined sequence, which resembles a piece of engineering.

  16. Large Mammalian Animal Models of Heart Disease

    PubMed Central

    Camacho, Paula; Fan, Huimin; Liu, Zhongmin; He, Jia-Qiang

    2016-01-01

    Due to the biological complexity of the cardiovascular system, the animal model is an urgent pre-clinical need to advance our knowledge of cardiovascular disease and to explore new drugs to repair the damaged heart. Ideally, a model system should be inexpensive, easily manipulated, reproducible, a biological representative of human disease, and ethically sound. Although a larger animal model is more expensive and difficult to manipulate, its genetic, structural, functional, and even disease similarities to humans make it an ideal model to first consider. This review presents the commonly-used large animals—dog, sheep, pig, and non-human primates—while the less-used other large animals—cows, horses—are excluded. The review attempts to introduce unique points for each species regarding its biological property, degrees of susceptibility to develop certain types of heart diseases, and methodology of induced conditions. For example, dogs barely develop myocardial infarction, while dilated cardiomyopathy is developed quite often. Based on the similarities of each species to the human, the model selection may first consider non-human primates—pig, sheep, then dog—but it also depends on other factors, for example, purposes, funding, ethics, and policy. We hope this review can serve as a basic outline of large animal models for cardiovascular researchers and clinicians. PMID:29367573

  17. Infections on the move: how transient phases of host movement influence disease spread

    PubMed Central

    Fenton, A.; Dell, A. I.

    2017-01-01

    Animal movement impacts the spread of human and wildlife diseases, and there is significant interest in understanding the role of migrations, biological invasions and other wildlife movements in spatial infection dynamics. However, the influence of processes acting on infections during transient phases of host movement is poorly understood. We propose a conceptual framework that explicitly considers infection dynamics during transient phases of host movement to better predict infection spread through spatial host networks. Accounting for host transient movement captures key processes that occur while hosts move between locations, which together determine the rate at which hosts spread infections through networks. We review theoretical and empirical studies of host movement and infection spread, highlighting the multiple factors that impact the infection status of hosts. We then outline characteristics of hosts, parasites and the environment that influence these dynamics. Recent technological advances provide disease ecologists unprecedented ability to track the fine-scale movement of organisms. These, in conjunction with experimental testing of the factors driving infection dynamics during host movement, can inform models of infection spread based on constituent biological processes. PMID:29263283

  18. A mathematical model on water redistribution mechanism of the seismonastic movement of Mimosa pudica.

    PubMed

    Kwan, K W; Ye, Z W; Chye, M L; Ngan, A H W

    2013-07-02

    A theoretical model based on the water redistribution mechanism is proposed to predict the volumetric strain of motor cells in Mimosa pudica during the seismonastic movement. The model describes the water and ion movements following the opening of ion channels triggered by stimulation. The cellular strain is related to the angular velocity of the plant movement, and both their predictions are in good agreement with experimental data, thus validating the water redistribution mechanism. The results reveal that an increase in ion diffusivity across the cell membrane of <15-fold is sufficient to produce the observed seismonastic movement. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  19. Current status of animal welfare and animal rights in China.

    PubMed

    Lu, Jiaqi; Bayne, Kathryn; Wang, Jianfei

    2013-11-01

    In the past few years, new social passions have sparked on the Chinese mainland. At the centre of these burgeoning passions is a focus on animal welfare, animal treatment, and even animal rights, by the public and academic sectors. With China's rapid economic changes and greater access to information from around the world, societal awareness of animal issues is rising very fast. Hastening this paradigm shift were several highly public incidents involving animal cruelty, including exposés on bear bile harvesting for traditional Chinese medicine, the thousands of dogs rescued from China's meat trade, and the call to boycott shark fin soup and bird nest soup. This article outlines the current status of campaigning by animal advocates in China (specifically the animal rights movement) from three interlinked perspectives: wildlife conservation, companion animal protection, and laboratory animal protection. By reviewing this campaigning, we attempt to present not only the political and social impact of the concept of animal rights, but also the perceptions of, and challenges to, animal rights activities in China. 2013 FRAME.

  20. Examining speed versus selection in connectivity models using elk migration as an example

    USGS Publications Warehouse

    Brennan, Angela; Hanks, EM; Merkle, JA; Cole, EK; Dewey, SR; Courtemanch, AB; Cross, Paul C.

    2018-01-01

    Context: Landscape resistance is vital to connectivity modeling and frequently derived from resource selection functions (RSFs). RSFs estimate relative probability of use and tend to focus on understanding habitat preferences during slow, routine animal movements (e.g., foraging). Dispersal and migration, however, can produce rarer, faster movements, in which case models of movement speed rather than resource selection may be more realistic for identifying habitats that facilitate connectivity. Objective: To compare two connectivity modeling approaches applied to resistance estimated from models of movement rate and resource selection. Methods: Using movement data from migrating elk, we evaluated continuous time Markov chain (CTMC) and movement-based RSF models (i.e., step selection functions [SSFs]). We applied circuit theory and shortest random path (SRP) algorithms to CTMC, SSF and null (i.e., flat) resistance surfaces to predict corridors between elk seasonal ranges. We evaluated prediction accuracy by comparing model predictions to empirical elk movements. Results: All models predicted elk movements well, but models applied to CTMC resistance were more accurate than models applied to SSF and null resistance. Circuit theory models were more accurate on average than SRP algorithms. Conclusions: CTMC can be more realistic than SSFs for estimating resistance for fast movements, though SSFs may demonstrate some predictive ability when animals also move slowly through corridors (e.g., stopover use during migration). High null model accuracy suggests seasonal range data may also be critical for predicting direct migration routes. For animals that migrate or disperse across large landscapes, we recommend incorporating CTMC into the connectivity modeling toolkit.