Fine-scale movement decisions of tropical forest birds in a fragmented landscape.

Science.gov (United States)

Gillies, Cameron S; Beyer, Hawthorne L; St Clair, Colleen Cassady

2011-04-01

The persistence of forest-dependent species in fragmented landscapes is fundamentally linked to the movement of individuals among subpopulations. The paths taken by dispersing individuals can be considered a series of steps built from individual route choices. Despite the importance of these fine-scale movement decisions, it has proved difficult to collect such data that reveal how forest birds move in novel landscapes. We collected unprecedented route information about the movement of translocated forest birds from two species in the highly fragmented tropical dry forest of Costa Rica. In this pasture-dominated landscape, forest remains in patches or riparian corridors, with lesser amounts of living fencerows and individual trees or "stepping stones." We used step selection functions to quantify how route choice was influenced by these habitat elements. We found that the amount of risk these birds were willing to take by crossing open habitat was context dependent. The forest-specialist Barred Antshrike (Thamnophilus doliatus) exhibited stronger selection for forested routes when moving in novel landscapes distant from its territory relative to locations closer to its territory. It also selected forested routes when its step originated in forest habitat. It preferred steps ending in stepping stones when the available routes had little forest cover, but avoided them when routes had greater forest cover. The forest-generalist Rufous-naped Wren (Campylorhynchus rufinucha) preferred steps that contained more pasture, but only when starting from non-forest habitats. Our results showed that forested corridors (i.e., riparian corridors) best facilitated the movement of a sensitive forest specialist through this fragmented landscape. They also suggested that stepping stones can be important in highly fragmented forests with little remaining forest cover. We expect that naturally dispersing birds and species with greater forest dependence would exhibit even stronger

A flexible GPS tracking system for studying bird behaviour at multiple scales

NARCIS (Netherlands)

Bouten, W.; Baaij, E.W.; Shamoun-Baranes, J.; Camphuysen, K.C.J.

2013-01-01

Tracking devices and bio-loggers provide crucial information on the ecology and behaviour of birds in their natural environment. An optimal tracking system should be lightweight, measure three-dimensional locations, enable flexible measurement schemes, transmit data remotely and measure

Application of ground-truth for classification and quantification of bird movements on migratory bird habitat initiative sites in southwest Louisiana: final report

Science.gov (United States)

Barrow, Wylie C.; Baldwin, Michael J.; Randall, Lori A.; Pitre, John; Dudley, Kyle J.

2013-01-01

surveys in the fall. Ducks (breeding and early migrating species) were also detected on diurnal surveys, but were less abundant than the previously mentioned taxa. Wading birds were the most abundant taxa observed during evening surveys up to 5 min before dusk when their numbers declined and duck densities increased. Ducks accounted for 64.0% of all birds detected from 0-5 min before dusk. Most ducks observed at that time were flyovers (71.4%), but circling (9.2%), departing (12.1%), and landing birds (7.4%) were also detected. In fall, the portable radar system detected two peaks in bird movement: one shortly before sunset and a second shortly after dusk. The later movement began just before dusk, peaked approximately 9 min after dusk, and concluded within 20 min after dusk. The flight headings of birds changed in relation to time from dusk. In general, the majority of targets flew towards the southwest before dusk and towards the northeast after dusk. The change in flight direction pre- and post-dusk may be related to movements dominated by migratory versus local flight. In winter, ducks, shorebirds, wading birds, and landbirds were the most abundant taxa in diurnal surveys. Geese were abundant at times, but their frequency of occurrence and densities were highly variable. The majority of ducks, shorebirds, and wading birds were observed feeding in MBHI fields. Landbirds and geese were more commonly seen resting. Overwintering ducks and geese dominated the movements near dusk (95.9% of all birds ≤ 5 min pre-dusk). Ducks were more frequently observed landing in (40.8%) and flying over (33.5%) MBHI fields while geese were mainly observed circling (54.7%) and flying over (38.9%) sites. Most of the shorebirds detected Shorebirds, ducks, and wading birds were the most abundant taxa during diurnal surveys of MBHI fields in spring, and the majority of individuals were observed actively foraging rather than resting. Breeding, overwintering, and transient migrant species were

Methods of quantitative and qualitative analysis of bird migration with a tracking radar

Science.gov (United States)

Bruderer, B.; Steidinger, P.

1972-01-01

Methods of analyzing bird migration by using tracking radar are discussed. The procedure for assessing the rate of bird passage is described. Three topics are presented concerning the grouping of nocturnal migrants, the velocity of migratory flight, and identification of species by radar echoes. The height and volume of migration under different weather conditions are examined. The methods for studying the directions of migration and the correlation between winds and the height and direction of migrating birds are presented.

Assisting doctors on assessing movements in infants using motion tracking

DEFF Research Database (Denmark)

Olsen, Mikkel; Herskind, Anna; Nielsen, Jens Bo

2015-01-01

In this work, we consider the possibilities of having an automatic computer-based system for tracking the movements of infants. An existing motion tracking system is used to process recorded video sequences containing both color and spatial information of the infant's body pose and movements....... The system uses these sequences of data to estimate the underlying skeleton of the infant and parametrize the movements. Post-processing of these parameters can yield objective measurements of an infant's movement patterns. This could e.g. be quantification of (a)symmetry and recognition of certain gestures/actions...

Real Time 3D Facial Movement Tracking Using a Monocular Camera

Directory of Open Access Journals (Sweden)

Yanchao Dong

2016-07-01

Full Text Available 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.

Research on Eye Movement Tracking in ESL Reading

Directory of Open Access Journals (Sweden)

Wenlian ZHAN

2014-06-01

Full Text Available Eye movement behavior in reading can reflect on-line cognitive process. Through the on-line measure of eye movement, under relatively natural reading condition, data of the reader’ s eye movement in the text can be obtained in processing information, and thus help to reveal the internal cognitive mechanisms in reading. With the development of intelligentization, serialization and portable direction in eye tracker, there exist great number of studies on eye movement tracking, but studies on eye movement features in ESL reading are rare. In such circumstances, this paper mainly illustrates eye movement patterns, the relationship between eye movement and perceptual processing, and eye movement control in ESL reading.

Nearly automatic motion capture system for tracking octopus arm movements in 3D space.

Science.gov (United States)

Zelman, Ido; Galun, Meirav; Akselrod-Ballin, Ayelet; Yekutieli, Yoram; Hochner, Binyamin; Flash, Tamar

2009-08-30

Tracking animal movements in 3D space is an essential part of many biomechanical studies. The most popular technique for human motion capture uses markers placed on the skin which are tracked by a dedicated system. However, this technique may be inadequate for tracking animal movements, especially when it is impossible to attach markers to the animal's body either because of its size or shape or because of the environment in which the animal performs its movements. Attaching markers to an animal's body may also alter its behavior. Here we present a nearly automatic markerless motion capture system that overcomes these problems and successfully tracks octopus arm movements in 3D space. The system is based on three successive tracking and processing stages. The first stage uses a recently presented segmentation algorithm to detect the movement in a pair of video sequences recorded by two calibrated cameras. In the second stage, the results of the first stage are processed to produce 2D skeletal representations of the moving arm. Finally, the 2D skeletons are used to reconstruct the octopus arm movement as a sequence of 3D curves varying in time. Motion tracking, segmentation and reconstruction are especially difficult problems in the case of octopus arm movements because of the deformable, non-rigid structure of the octopus arm and the underwater environment in which it moves. Our successful results suggest that the motion-tracking system presented here may be used for tracking other elongated objects.

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

Science.gov (United States)

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.

Identifying Anxiety Through Tracked Head Movements in a Virtual Classroom.

Science.gov (United States)

Won, Andrea Stevenson; Perone, Brian; Friend, Michelle; Bailenson, Jeremy N

2016-06-01

Virtual reality allows the controlled simulation of complex social settings, such as classrooms, and thus provides an opportunity to test a range of theories in the social sciences in a way that is both naturalistic and controlled. Importantly, virtual environments also allow the body movements of participants in the virtual world to be tracked and recorded. In the following article, we discuss how tracked head movements were correlated with participants' reports of anxiety in a simulation of a classroom. Participants who reported a high sense of awareness of and concern about the other virtual people in the room showed different patterns of head movement (more lateral head movement, indicating scanning behavior) from those who reported a low level of concern. We discuss the implications of this research for understanding nonverbal behavior associated with anxiety and for the design of online educational systems.

Tracking boundary movement and exterior shape modelling in lung EIT imaging

International Nuclear Information System (INIS)

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

2015-01-01

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. (paper)

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

Science.gov (United States)

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.

Cumulative Effects of Barriers on the Movements of Forest Birds

Directory of Open Access Journals (Sweden)

Marc Bélisle

2002-01-01

Full Text Available Although there is a consensus of opinion that habitat fragmentation has deleterious effects on animal populations, primarily by inhibiting dispersal among remaining patches, there have been few explicit demonstrations of the ways by which degraded habitats actually constrain individual movement. Two impediments are primarily responsible for this paucity: it is difficult to separate the effects of habitat fragmentation (configuration from habitat loss (composition, and conventional measures of fragmented habitats are assumed to be, but probably are not, isotropic. We addressed these limitations by standardizing differences in forest cover in a clearly anisotropic configuration of habitat fragmentation by conducting a homing experiment with three species of forest birds in the Bow Valley of Banff National Park, Canada. Birds were translocated (1.2-3.5  km either parallel or perpendicular to four/five parallel barriers that are assumed to impede the cross-valley travel of forest-dependent animals. Taken together, individuals exhibited longer return times when they were translocated across these barriers, but differences among species suggest a more complex interpretation. A long-distance migrant (Yellow-rumped Warbler, Dendroica coronata behaved as predicted, but a short-distance migrant (Golden-crowned Kinglet, Regulus satrapa was indifferent to barrier configuration. A resident (Red-breasted Nuthatch, Sitta canadensis exhibited longer return times when it was translocated parallel to the barriers. Our results suggest that an anisotropic arrangement of small, open areas in fragmented landscapes can have a cumulative barrier effect on the movement of forest animals, but that both modelers and managers will have to acknowledge potentially counterintuitive differences among species to predict the effect that these may have on individual movement and, ultimately, dispersal.

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

Science.gov (United States)

Hines, James; Powell, Luke L.; Wolfe, Jared D.; Johnson, Erik l.; Nichols, James D.; Stouffer, Phillip C.

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 radiotelemetry data to determine the successional stage at which within-day movement probabilities of Amazonian birds in secondary forest are similar to those in primary forest. We radio-tracked three common understory insectivore species in primary and secondary forest at the Biological Dynamics of Forest Fragments project near Manaus, Brazil: two woodcreepers, Glyphorynchus spirurus (n = 19) andXiphorhynchus pardalotus (n = 18), and the terrestrial antthrush Formicarius colma(n = 19). Forest age was a strong predictor of fidelity to a given habitat. All three species showed greater fidelity to primary forest than to 8–14-year-old secondary forest, indicating the latter’s relatively poor quality. The two woodcreeper species used 12–18-year-old secondary forest in a manner comparable to continuous forest, but F. colmaavoided moving even to 27–31-year-old secondary forest—the oldest at our site. Our results suggest that managers concerned with less sensitive species can assume that forest reserves connected by 12–18-year-old secondary forest corridors are effectively connected. On the other hand, >30 years are required after land abandonment before secondary forest serves as a primary forest-like conduit for movement by F. colma; more sensitive terrestrial insectivores may take longer still.

A Hidden Markov Movement Model for rapidly identifying behavioral states from animal tracks

DEFF Research Database (Denmark)

Whoriskey, Kim; Auger-Méthé, Marie; Albertsen, Christoffer Moesgaard

2017-01-01

by fitting it to real tracks from a grey seal, lake trout, and blue shark, as well as to simulated data. 4. The HMMM is a fast and reliable tool for making meaningful inference from animal movement data that is ideally suited for ecologists who want to use the popular DCRWS implementation for highly accurate......1. Electronic telemetry is frequently used to document animal movement through time. Methods that can identify underlying behaviors driving specific movement patterns can help us understand how and why animals use available space, thereby aiding conservation and management efforts. For aquatic...... animal tracking data with significant measurement error, a Bayesian state-space model called the first-Difference Correlated Random Walk with Switching (DCRWS) has often been used for this purpose. However, for aquatic animals, highly accurate tracking data of animal movement are now becoming more common...

Commodity movement tracking (CMT) : bridging operations and commercial transactions

International Nuclear Information System (INIS)

Lewyta, M.

2004-01-01

Enbridge Pipelines Inc. (EPI) operates a network of interconnected pipelines that facilitate the transport of liquid fuels across North America, with operations centralized in Edmonton, Alberta. This paper addressed the issue of accurately tracking the location of commodities transported on EPI pipelines for billing and payment purposes. The role of integrated information systems in meeting the need for high quality information by customers and by EPI was also addressed. The paper presented the Commodity Movement Tracking (CMT) system that is central to achieving the desired accuracy of commercial and financial transactions. CMT tracks inventories and links products to commercial transactions across the pipeline. Batches are tracked from initial receipt to final delivery, incorporating CMT's operational checks and balances, reconciliation steps, process monitoring, and supervisory control and data acquisition (SCADA) systems data that contribute to inputs equaling outputs. Daily schedules are recorded into the CMT system as events, based on volumetric information derived from the SCADA system. Receipt and delivery events will be electronically recorded into CMT from field flow computers in the near future. CMT modeling considers changes within the line configuration, static pipe diameter changes, as well as packing and draining of the line fill resulting from pressure changes. This paper described the major functional activities of the overall business process, such as nominations, scheduling, commodity movement tracking, leak detection, electronic ticketing, SCADA, and oil accounting. 10 figs.

Quantitative analysis of the TMJ movement with a new mandibular movement tracking and simulation system

International Nuclear Information System (INIS)

Kim, Dae Seung; Hwang, Soon Jung; Choi, Soon Chul; Lee, Sam Sun; Heo, Min Suk; Heo, Kyung Hoe; Yi, Won Jin

2008-01-01

The purpose of this study was to develop a system for the measurement and simulation of the TMJ movement and to analyze the mandibular movement quantitatively. We devised patient-specific splints and a registration body for the TMJ movement tracking. The mandibular movements of the 12 subjects with facial deformity and 3 controls were obtained by using an optical tracking system and the patient-specific splints. The mandibular part was manually segmented from the CT volume data of a patient. Three-dimensional surface models of the maxilla and the mandible were constructed using the segmented data. The continuous movement of the mandible with respect to the maxilla could be simulated by applying the recorded positions sequentially. Trajectories of the selected reference points were calculated during simulation and analyzed. The selected points were the most superior point of bilateral condyle, lower incisor point, and pogonion. There were significant differences (P<0.05) between control group and pre-surgical group in the maximum displacement of left superior condyle, lower incisor, and pogonion in vertical direction. Differences in the maximum lengths of the right and the left condyle were 0.59 ± 0.30 mm in pre-surgical group and 2.69 ± 2.63 mm in control group, which showed a significant difference (P<0.005). The maximum of differences between lengths of the right and the left calculated during one cycle also showed a significant difference between two groups (P<0.05). Significant differences in mandibular movements between the groups implies that facial deformity have an effect on the movement asymmetry of the mandible.

Studying the movement behaviour of benthic macroinvertebrates with automated video tracking

NARCIS (Netherlands)

Augusiak, J.A.; Brink, van den P.J.

2015-01-01

Quantifying and understanding movement is critical for a wide range of questions in basic and applied ecology. Movement ecology is also fostered by technological advances that allow automated tracking for a wide range of animal species. However, for aquatic macroinvertebrates, such detailed methods

Results from the first GPS tracking of roof-nesting Herring Gulls Larus argentatus in the UK

NARCIS (Netherlands)

Rock, P.; Camphuysen, C.J.; Shamoun-Baranes, J.; Ross-Smith, V.; Vaughan, I.P.

2016-01-01

Recent developments in GPS tracking technology allow the movements of bird species to be followed in ever-greater detail. Seabird research is benefiting greatly, due to the challenges of tracking species that often roam widely out at sea. Amongst the gulls, one of the pressing issues is to

Overwintering strategies of migratory birds: a novel approach for estimating seasonal movement patterns of residents and transients

Science.gov (United States)

Ruiz-Gutierrez, Viviana; Kendall, William L.; Saracco, James F.; White, Gary C.

2016-01-01

Our understanding of movement patterns in wildlife populations has played an important role in current ecological knowledge and can inform landscape conservation decisions. Direct measures of movement can be obtained using marked individuals, but this requires tracking individuals across a landscape or multiple sites.We demonstrate how movements can be estimated indirectly using single-site, capture–mark–recapture (CMR) data with a multi-state open robust design with state uncertainty model (MSORD-SU). We treat residence and transience as two phenotypic states of overwintering migrants and use time- and state-dependent probabilities of site entry and persistence as indirect measures of movement. We applied the MSORD-SU to data on eight species of overwintering Neotropical birds collected in 14 countries between 2002 and 2011. In addition to entry and persistence probabilities, we estimated the proportions of residents at a study site and mean residence times.We identified overwintering movement patterns and residence times that contrasted with prior categorizations of territoriality. Most species showed an evidence of residents entering sites at multiple time intervals, with transients tending to enter between peak resident movement times. Persistence and the proportion of residents varied by latitude, but were not always positively correlated for a given species.Synthesis and applications. Our results suggest that migratory songbirds commonly move among habitats during the overwintering period. Substantial proportions of populations appear to be comprised of transient individuals, and residents tend to persist at specific sites for relatively short periods of time. This information on persistence and movement patterns should be explored for specific habitats to guide landscape management on the wintering grounds, such as determining which habitats are conserved or restored as part of certification programmes of tropical agroforestry crops. We suggest that

Mobbing call experiment suggests the enhancement of forest bird movement by tree cover in urban landscapes across seasons

Directory of Open Access Journals (Sweden)

Atsushi Shimazaki

2017-06-01

Full Text Available Local scale movement behavior is an important basis to predict large-scale bird movements in heterogeneous landscapes. Here we conducted playback experiments using mobbing calls to estimate the probability that forest birds would cross a 50-m urban area during three seasons (breeding, dispersal, and wintering seasons with varying amounts of tree cover, building area, and electric wire density. We examined the responses of four forest resident species: Marsh Tit (Poecile palustris, Varied Tit (Sittiparus varius, Japanese Tit (P. minor, and Eurasian Nuthatch (Sitta europaea in central Hokkaido, northern Japan. We carried out and analyzed 250 playback experiments that attracted 618 individuals. Our results showed that tree cover increased the crossing probability of three species other than Varied Tit. Building area and electric wire density had no detectable effect on crossing probability for four species. Seasonal difference in the crossing probability was found only for Varied Tit, and the probability was the highest in the breeding season. These results suggest that the positive effect of tree cover on the crossing probability would be consistent across seasons. We therefore conclude that planting trees would be an effective way to promote forest bird movement within an urban landscape.

GPS tracking data of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast.

Science.gov (United States)

Stienen, Eric W M; Desmet, Peter; Aelterman, Bart; Courtens, Wouter; Feys, Simon; Vanermen, Nicolas; Verstraete, Hilbran; de Walle, Marc Van; Deneudt, Klaas; Hernandez, Francisco; Houthoofdt, Robin; Vanhoorne, Bart; Bouten, Willem; Buijs, Roland-Jan; Kavelaars, Marwa M; Müller, Wendt; Herman, David; Matheve, Hans; Sotillo, Alejandro; Lens, Luc

2016-01-01

In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF).

Role of bird movements in the epidemiology of West Nile and avian influenza virus

Science.gov (United States)

Muzaffar, Sabir Bin; Hill, Nichola J.; Takekawa, John Y.; Perry, William M.; Smith, Lacy M.; Boyce, Walter M.

2012-01-01

Avian infl uenza virus (AIV) is infl uenced by site fi delity and movements of bird hosts. We examined the movement ecology of American crows (Corvus brachyrhynchos) as potential hosts for West Nile virus (WNV) and greater white-fronted geese (Anser albifrons frontalis) as potential hosts for AIVs. Research was based on radio-telemetry studies conducted in the Central Valley of California, USA. While crows were restricted to a small area of only a few square kilometers, the distribution of the geese encompassed the northern Central Valley. The crows used 1.5 to 3.5 different roosting areas monthly from February through October, revealing lower roost fi delity than the geese that used 1.1 to 1.5 roosting areas each month from November through March. The crows moved a mean distance of 0.11 to 0.49 km/month between their roosting sites and 2.5 to 3.9 km/month between roosting and feeding sites. In contrast, the geese moved 4.2 to 19.3 km/month between roosting areas, and their feeding range varied from 13.2 to 19.0 km/month. Our comparison of the ecological characteristics of bird movements suggests that the limited local movements of crows coupled with frequent turnover of roosts may result in persistence of focal areas for WNV infection. In contrast, widespread areas used by geese will provide regular opportunities for intermixing of AIVs over a much greater geographic area.

Assessing the impact of marine wind farms on birds through movement modelling

OpenAIRE

Masden, Elizabeth A.; Reeve, Richard; Desholm, Mark; Fox, Anthony D.; Furness, Robert W.; Haydon, Daniel T.

2012-01-01

Advances in technology and engineering, along with European Union renewable energy targets, have stimulated a rapid growth of the wind power sector. Wind farms contribute to carbon emission reductions, but there is a need to ensure that these structures do not adversely impact the populations that interact with them, particularly birds. We developed movement models based on observed avoidance responses of common eider Somateria mollissima to wind farms to predict, and identify potential measu...

Using Motion Tracking to Detect Spontaneous Movements in Infants

DEFF Research Database (Denmark)

Olsen, Mikkel Damgaard; Herskind, Anna; Nielsen, Jens Bo

2015-01-01

We study the characteristics of infants’ spontaneous movements, based on data obtained from a markerless motion tracking system. From the pose data, the set of features are generated from the raw joint-angles of the infants and different classifiers are trained and evaluated using annotated data...

Tracking the Eye Movement of Four Years Old Children Learning Chinese Words

Science.gov (United States)

Lin, Dan; Chen, Guangyao; Liu, Yingyi; Liu, Jiaxin; Pan, Jue; Mo, Lei

2018-01-01

Storybook reading is the major source of literacy exposure for beginning readers. The present study tracked 4-year-old Chinese children's eye movements while they were reading simulated storybook pages. Their eye-movement patterns were examined in relation to their word learning gains. The same reading list, consisting of 20 two-character Chinese…

Species distribution models for a migratory bird based on citizen science and satellite tracking data

Directory of Open Access Journals (Sweden)

Christopher L. Coxen

2017-07-01

Full Text Available Species distribution models can provide critical baseline distribution information for the conservation of poorly understood species. Here, we compared the performance of band-tailed pigeon (Patagioenas fasciata species distribution models created using Maxent and derived from two separate presence-only occurrence data sources in New Mexico: 1 satellite tracked birds and 2 observations reported in eBird basic data set. Both models had good accuracy (test AUC > 0.8 and True Skill Statistic > 0.4, and high overlap between suitability scores (I statistic 0.786 and suitable habitat patches (relative rank 0.639. Our results suggest that, at the state-wide level, eBird occurrence data can effectively model similar species distributions as satellite tracking data. Climate change models for the band-tailed pigeon predict a 35% loss in area of suitable climate by 2070 if CO2 emissions drop to 1990 levels by 2100, and a 45% loss by 2070 if we continue current CO2 emission levels through the end of the century. These numbers may be conservative given the predicted increase in drought, wildfire, and forest pest impacts to the coniferous forests the species inhabits in New Mexico. The northern portion of the species’ range in New Mexico is predicted to be the most viable through time.

Species distribution models for a migratory bird based on citizen science and satellite tracking data

Science.gov (United States)

Coxen, Christopher L.; Frey, Jennifer K.; Carleton, Scott A.; Collins, Daniel P.

2017-01-01

Species distribution models can provide critical baseline distribution information for the conservation of poorly understood species. Here, we compared the performance of band-tailed pigeon (Patagioenas fasciata) species distribution models created using Maxent and derived from two separate presence-only occurrence data sources in New Mexico: 1) satellite tracked birds and 2) observations reported in eBird basic data set. Both models had good accuracy (test AUC > 0.8 and True Skill Statistic > 0.4), and high overlap between suitability scores (I statistic 0.786) and suitable habitat patches (relative rank 0.639). Our results suggest that, at the state-wide level, eBird occurrence data can effectively model similar species distributions as satellite tracking data. Climate change models for the band-tailed pigeon predict a 35% loss in area of suitable climate by 2070 if CO2 emissions drop to 1990 levels by 2100, and a 45% loss by 2070 if we continue current CO2 emission levels through the end of the century. These numbers may be conservative given the predicted increase in drought, wildfire, and forest pest impacts to the coniferous forests the species inhabits in New Mexico. The northern portion of the species’ range in New Mexico is predicted to be the most viable through time.

4-D single particle tracking of synthetic and proteinaceous microspheres reveals preferential movement of nuclear particles along chromatin - poor tracks.

Science.gov (United States)

Bacher, Christian P; Reichenzeller, Michaela; Athale, Chaitanya; Herrmann, Harald; Eils, Roland

2004-11-23

The dynamics of nuclear organization, nuclear bodies and RNPs in particular has been the focus of many studies. To understand their function, knowledge of their spatial nuclear position and temporal translocation is essential. Typically, such studies generate a wealth of data that require novel methods in image analysis and computational tools to quantitatively track particle movement on the background of moving cells and shape changing nuclei. We developed a novel 4-D image processing platform (TIKAL) for the work with laser scanning and wide field microscopes. TIKAL provides a registration software for correcting global movements and local deformations of cells as well as 2-D and 3-D tracking software. With this new tool, we studied the dynamics of two different types of nuclear particles, namely nuclear bodies made from GFP-NLS-vimentin and microinjected 0.1 mum - wide polystyrene beads, by live cell time-lapse microscopy combined with single particle tracking and mobility analysis. We now provide a tool for the automatic 3-D analysis of particle movement in parallel with the acquisition of chromatin density data. Kinetic analysis revealed 4 modes of movement: confined obstructed, normal diffusion and directed motion. Particle tracking on the background of stained chromatin revealed that particle movement is directly related to local reorganization of chromatin. Further a direct comparison of particle movement in the nucleoplasm and the cytoplasm exhibited an entirely different kinetic behaviour of vimentin particles in both compartments. The kinetics of nuclear particles were slightly affected by depletion of ATP and significantly disturbed by disruption of actin and microtubule networks. Moreover, the hydration state of the nucleus had a strong impact on the mobility of nuclear bodies since both normal diffusion and directed motion were entirely abolished when cells were challenged with 0.6 M sorbitol. This effect correlated with the compaction of chromatin

4-D single particle tracking of synthetic and proteinaceous microspheres reveals preferential movement of nuclear particles along chromatin – poor tracks

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Athale Chaitanya

2004-11-01

Full Text Available Abstract Background The dynamics of nuclear organization, nuclear bodies and RNPs in particular has been the focus of many studies. To understand their function, knowledge of their spatial nuclear position and temporal translocation is essential. Typically, such studies generate a wealth of data that require novel methods in image analysis and computational tools to quantitatively track particle movement on the background of moving cells and shape changing nuclei. Results We developed a novel 4-D image processing platform (TIKAL for the work with laser scanning and wide field microscopes. TIKAL provides a registration software for correcting global movements and local deformations of cells as well as 2-D and 3-D tracking software. With this new tool, we studied the dynamics of two different types of nuclear particles, namely nuclear bodies made from GFP-NLS-vimentin and microinjected 0.1 μm – wide polystyrene beads, by live cell time-lapse microscopy combined with single particle tracking and mobility analysis. We now provide a tool for the automatic 3-D analysis of particle movement in parallel with the acquisition of chromatin density data. Conclusions Kinetic analysis revealed 4 modes of movement: confined obstructed, normal diffusion and directed motion. Particle tracking on the background of stained chromatin revealed that particle movement is directly related to local reorganization of chromatin. Further a direct comparison of particle movement in the nucleoplasm and the cytoplasm exhibited an entirely different kinetic behaviour of vimentin particles in both compartments. The kinetics of nuclear particles were slightly affected by depletion of ATP and significantly disturbed by disruption of actin and microtubule networks. Moreover, the hydration state of the nucleus had a strong impact on the mobility of nuclear bodies since both normal diffusion and directed motion were entirely abolished when cells were challenged with 0.6 M

4-D single particle tracking of synthetic and proteinaceous microspheres reveals preferential movement of nuclear particles along chromatin – poor tracks

Science.gov (United States)

Bacher, Christian P; Reichenzeller, Michaela; Athale, Chaitanya; Herrmann, Harald; Eils, Roland

2004-01-01

Background The dynamics of nuclear organization, nuclear bodies and RNPs in particular has been the focus of many studies. To understand their function, knowledge of their spatial nuclear position and temporal translocation is essential. Typically, such studies generate a wealth of data that require novel methods in image analysis and computational tools to quantitatively track particle movement on the background of moving cells and shape changing nuclei. Results We developed a novel 4-D image processing platform (TIKAL) for the work with laser scanning and wide field microscopes. TIKAL provides a registration software for correcting global movements and local deformations of cells as well as 2-D and 3-D tracking software. With this new tool, we studied the dynamics of two different types of nuclear particles, namely nuclear bodies made from GFP-NLS-vimentin and microinjected 0.1 μm – wide polystyrene beads, by live cell time-lapse microscopy combined with single particle tracking and mobility analysis. We now provide a tool for the automatic 3-D analysis of particle movement in parallel with the acquisition of chromatin density data. Conclusions Kinetic analysis revealed 4 modes of movement: confined obstructed, normal diffusion and directed motion. Particle tracking on the background of stained chromatin revealed that particle movement is directly related to local reorganization of chromatin. Further a direct comparison of particle movement in the nucleoplasm and the cytoplasm exhibited an entirely different kinetic behaviour of vimentin particles in both compartments. The kinetics of nuclear particles were slightly affected by depletion of ATP and significantly disturbed by disruption of actin and microtubule networks. Moreover, the hydration state of the nucleus had a strong impact on the mobility of nuclear bodies since both normal diffusion and directed motion were entirely abolished when cells were challenged with 0.6 M sorbitol. This effect correlated

Nieuwe ontdekkingen en mogelijkheden in het onderzoek aan Scholeksters dankzij het UvA Bird Tracking Systeem

NARCIS (Netherlands)

Ens, B. J.; Bom, R. A.; Dokter, A. M.; Oosterbeek, K.; de Jong, Jan; Bouten, W.

2014-01-01

This paper reports on new discoveries and new possibilities due to the deployment of the UvA Bird Tracking System (UvA-BiTS; Bouten et al. 2013) in our investigations of the behavioural ecology of Oystercatchers. This GPS tracker is powered by solar cells and not only stores GPS locations, but also

Spatial and temporal movements in Pyrenean bearded vultures (Gypaetus barbatus): Integrating movement ecology into conservation practice.

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Margalida, Antoni; Pérez-García, Juan Manuel; Afonso, Ivan; Moreno-Opo, Rubén

2016-10-25

Understanding the movement of threatened species is important if we are to optimize management and conservation actions. Here, we describe the age and sex specific spatial and temporal ranging patterns of 19 bearded vultures Gypaetus barbatus tracked with GPS technology. Our findings suggest that spatial asymmetries are a consequence of breeding status and age-classes. Territorial individuals exploited home ranges of about 50 km 2 , while non-territorial birds used areas of around 10 000 km 2 (with no seasonal differences). Mean daily movements differed between territorial (23.8 km) and non-territorial birds (46.1 km), and differences were also found between sexes in non-territorial birds. Daily maximum distances travelled per day also differed between territorial (8.2 km) and non-territorial individuals (26.5 km). Territorial females moved greater distances (12 km) than males (6.6 km). Taking into account high-use core areas (K20), Supplementary Feeding Sites (SFS) do not seem to play an important role in the use of space by bearded vultures. For non-territorial and territorial individuals, 54% and 46% of their home ranges (K90), respectively, were outside protected areas. Our findings will help develop guidelines for establishing priority areas based on spatial use, and also optimize management and conservation actions for this threatened species.

Extracting information of fixational eye movements through pupil tracking

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Xiao, JiangWei; Qiu, Jian; Luo, Kaiqin; Peng, Li; Han, Peng

2018-01-01

Human eyes are never completely static even when they are fixing a stationary point. These irregular, small movements, which consist of micro-tremors, micro-saccades and drifts, can prevent the fading of the images that enter our eyes. The importance of researching the fixational eye movements has been experimentally demonstrated recently. However, the characteristics of fixational eye movements and their roles in visual process have not been explained clearly, because these signals can hardly be completely extracted by now. In this paper, we developed a new eye movement detection device with a high-speed camera. This device includes a beam splitter mirror, an infrared light source and a high-speed digital video camera with a frame rate of 200Hz. To avoid the influence of head shaking, we made the device wearable by fixing the camera on a safety helmet. Using this device, the experiments of pupil tracking were conducted. By localizing the pupil center and spectrum analysis, the envelope frequency spectrum of micro-saccades, micro-tremors and drifts are shown obviously. The experimental results show that the device is feasible and effective, so that the device can be applied in further characteristic analysis.

Tracking the movements of a post-nesting Southern River Terrapin (Batagur affinis edwardmolli)

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Chen, Pelf-Nyok; Wong, Adrian

2015-09-01

A Southern River Terrapin (Batagur affinis edwardmolli) Conservation Project was initiated on one terrapin nesting bank in 2011, following the discovery of a River Terrapin population in the Kemaman River, Terengganu in 2010. Since this project was initiated, Turtle Conservation Society of Malaysia (TCS) was instrumental in the gazettement of three nesting banks along the Kemaman River, from which all River Terrapin eggs are collected for incubation. However, there are at least a dozen other "unprotected" nesting banks along the river, where all eggs were collected for human consumption. This project attempted to determine the movements of a post-nesting River Terrapin, with hopes that it would provide the preliminary baseline information on the utilization of adjacent nesting banks. The solution was a GPS tracking device that transmitted coordinates every hour over cellular networks. Location-based data was sent via Short Message Service (SMS) to our own SMS gateway running on a Raspberry Pi credit-card size computer, which was then logged in a database and presented graphically via Google Maps. It was a complete tracking and monitoring system. This solution enabled researchers to remotely track the movements of a River Terrapin, hence reducing the costs of research. The movements of a post-nesting River Terrapin were tracked for eight days before the battery was drained. On the third day, this River Terrapin ascended an adjacent riverbank and spent less than an hour on the bank, presumably to deposit her remaining eggs. This study confirmed that River Terrapins do utilize other suitable nesting banks if/whenever available. Results from such tracking studies will be used to leverage on the protection of adjacent nesting banks, thus providing greater protection for the critically endangered River Terrapins.

Detection of lung tumor movement in real-time tumor-tracking radiotherapy

International Nuclear Information System (INIS)

Shimizu, Shinichi; Shirato, Hiroki; Ogura, Shigeaki; Akita-Dosaka, Hirotoshi; Kitamura, Kei; Nishioka, Takeshi; Kagei, Kenji; Nishimura, Masaji; Miyasaka, Kazuo

2001-01-01

Purpose: External radiotherapy for lung tumors requires reducing the uncertainty due to setup error and organ motion. We investigated the three-dimensional movement of lung tumors through an inserted internal marker using a real-time tumor-tracking system and evaluated the efficacy of this system at reducing the internal margin. Methods and Materials: Four patients with lung cancer were analyzed. A 2.0-mm gold marker was inserted into the tumor. The real-time tumor-tracking system calculates and stores three-dimensional coordinates of the marker 30 times/s. The system can trigger the linear accelerator to irradiate the tumor only when the marker is located within the predetermined 'permitted dislocation'. The value was set at ±1 to ±3 mm according to the patient's characteristics. We analyzed 10,413-14,893 data sets for each of the 4 patients. The range of marker movement during normal breathing (beam-off period) was compared with that during gated irradiation (beam-on period) by Student's t test. Results: The range of marker movement during the beam-off period was 5.5-10.0 mm in the lateral direction (x), 6.8-15.9 mm in the craniocaudal direction (y) and 8.1-14.6 mm in the ventrodorsal direction (z). The range during the beam-on period was reduced to within 5.3 mm in all directions in all 4 patients. A significant difference was found between the mean of the range during the beam-off period and the mean of the range during the beam-on period in the x (p=0.007), y (p=0.025), and z (p=0.002) coordinates, respectively. Conclusion: The real-time tumor-tracking radiotherapy system was useful to analyze the movement of an internal marker. Treatment with megavoltage X-rays was properly given when the tumor marker moved into the 'permitted dislocation' zone from the planned position

Site Safety and Food Affect Movements of Semipalmated Sandpipers (Calidris pusilla Migrating Through the Upper Bay of Fundy

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Ashley J. Sprague

2008-12-01

Full Text Available The upper Bay of Fundy is a critical stopover site for Semipalmated Sandpipers (Calidris pusilla during their fall migration. However, little is known about factors that influence selection of feeding and roosting sites by these birds, or the extent to which birds move between different sites during their time in the region. Using radio-telemetry, we studied movement patterns, examined habitat use, and tested hypotheses associated with factors influencing foraging and roost-site selection. Movements of radio-tagged sandpipers were tracked in the upper Bay of Fundy in August 2004 and 2005. In 2004, sandpipers from the Minas Basin, Nova Scotia and Chignecto Bay, New Brunswick and Nova Scotia, were tracked, and in 2005, sandpipers were tracked only in Chignecto Bay. Sandpipers were highly mobile in both the Minas Basin 2004 and Chignecto Bay 2005, making daily movements of up to 20 km between foraging and roosting sites, although very little movement was detected in Chignecto Bay in 2004. Migrating sandpipers appeared to select foraging sites based on relative safety, as measured by distance to cover, provided that these sites offered an adequate food supply. Similarly, roosting sandpipers preferred sites that were far from nearby trees that might offer cover to predators. This preference for safe sites became more apparent later in their stay in the Bay of Fundy, when birds were heavier and, therefore, possibly more vulnerable to predation. Semipalmated Sandpipers appear to be flexible during their time in the upper Bay of Fundy, displaying year-to-year and site-to-site variability in movement and mudflat usage. Therefore, multiple, synchronized population counts should be conducted at known roost sites in order to more accurately estimate Semipalmated Sandpiper abundance in this region. Furthermore, in a highly dynamic system where food can be variable, landscape features such as distance to cover may be important factors to consider when

ESTIMATION OF SHIE GLACIER SURFACE MOVEMENT USING OFFSET TRACKING TECHNIQUE WITH COSMO-SKYMED IMAGES

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Q. Wang

2017-09-01

Full Text Available Movement is one of the most important characteristics of glaciers which can cause serious natural disasters. For this reason, monitoring this massive blocks is a crucial task. Synthetic Aperture Radar (SAR can operate all day in any weather conditions and the images acquired by SAR contain intensity and phase information, which are irreplaceable advantages in monitoring the surface movement of glaciers. Moreover, a variety of techniques like DInSAR and offset tracking, based on the information of SAR images, could be applied to measure the movement. Sangwang lake, a glacial lake in the Himalayas, has great potentially danger of outburst. Shie glacier is situated at the upstream of the Sangwang lake. Hence, it is significant to monitor Shie glacier surface movement to assess the risk of outburst. In this paper, 6 high resolution COSMO-SkyMed images spanning from August to December, 2016 are applied with offset tracking technique to estimate the surface movement of Shie glacier. The maximum velocity of Shie glacier surface movement is 51 cm/d, which was observed at the end of glacier tongue, and the velocity is correlated with the change of elevation. Moreover, the glacier surface movement in summer is faster than in winter and the velocity decreases as the local temperature decreases. Based on the above conclusions, the glacier may break off at the end of tongue in the near future. The movement results extracted in this paper also illustrate the advantages of high resolution SAR images in monitoring the surface movement of small glaciers.

Estimation of Shie Glacier Surface Movement Using Offset Tracking Technique with Cosmo-Skymed Images

Science.gov (United States)

Wang, Q.; Zhou, W.; Fan, J.; Yuan, W.; Li, H.; Sousa, J. J.; Guo, Z.

2017-09-01

Movement is one of the most important characteristics of glaciers which can cause serious natural disasters. For this reason, monitoring this massive blocks is a crucial task. Synthetic Aperture Radar (SAR) can operate all day in any weather conditions and the images acquired by SAR contain intensity and phase information, which are irreplaceable advantages in monitoring the surface movement of glaciers. Moreover, a variety of techniques like DInSAR and offset tracking, based on the information of SAR images, could be applied to measure the movement. Sangwang lake, a glacial lake in the Himalayas, has great potentially danger of outburst. Shie glacier is situated at the upstream of the Sangwang lake. Hence, it is significant to monitor Shie glacier surface movement to assess the risk of outburst. In this paper, 6 high resolution COSMO-SkyMed images spanning from August to December, 2016 are applied with offset tracking technique to estimate the surface movement of Shie glacier. The maximum velocity of Shie glacier surface movement is 51 cm/d, which was observed at the end of glacier tongue, and the velocity is correlated with the change of elevation. Moreover, the glacier surface movement in summer is faster than in winter and the velocity decreases as the local temperature decreases. Based on the above conclusions, the glacier may break off at the end of tongue in the near future. The movement results extracted in this paper also illustrate the advantages of high resolution SAR images in monitoring the surface movement of small glaciers.

Using sutures to attach miniature tracking tags to small bats for multimonth movement and behavioral studies.

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Castle, Kevin T; Weller, Theodore J; Cryan, Paul M; Hein, Cris D; Schirmacher, Michael R

2015-07-01

Determining the detailed movements of individual animals often requires them to carry tracking devices, but tracking broad-scale movement of small bats (system (GPS) tags and geolocating data loggers to small bats. We used monofilament, synthetic, absorbable sutures to secure GPS tags and data loggers to the skin of anesthetized big brown bats (Eptesicus fuscus) in Colorado and hoary bats (Lasiurus cinereus) in California. GPS tags and data loggers were sutured to 17 bats in this study. Three tagged bats were recaptured 7 months after initial deployment, with tags still attached; none of these bats showed ill effects from the tag. No severe injuries were apparent upon recapture of 6 additional bats that carried tags up to 26 days after attachment; however, one of the bats exhibited skin chafing. Use of absorbable sutures to affix small tracking devices seems to be a safe, effective method for studying movements of bats over multiple months, although additional testing is warranted. This new attachment method has the potential to quickly advance our understanding of small bats, particularly as more sophisticated miniature tracking devices (e.g., satellite tags) become available.

BORC Functions Upstream of Kinesins 1 and 3 to Coordinate Regional Movement of Lysosomes along Different Microtubule Tracks.

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Guardia, Carlos M; Farías, Ginny G; Jia, Rui; Pu, Jing; Bonifacino, Juan S

2016-11-15

The multiple functions of lysosomes are critically dependent on their ability to undergo bidirectional movement along microtubules between the center and the periphery of the cell. Centrifugal and centripetal movement of lysosomes is mediated by kinesin and dynein motors, respectively. We recently described a multi-subunit complex named BORC that recruits the small GTPase Arl8 to lysosomes to promote their kinesin-dependent movement toward the cell periphery. Here, we show that BORC and Arl8 function upstream of two structurally distinct kinesin types: kinesin-1 (KIF5B) and kinesin-3 (KIF1Bβ and KIF1A). Remarkably, KIF5B preferentially moves lysosomes on perinuclear tracks enriched in acetylated α-tubulin, whereas KIF1Bβ and KIF1A drive lysosome movement on more rectilinear, peripheral tracks enriched in tyrosinated α-tubulin. These findings establish BORC as a master regulator of lysosome positioning through coupling to different kinesins and microtubule tracks. Common regulation by BORC enables coordinate control of lysosome movement in different regions of the cell. Published by Elsevier Inc.

Tracking without perceiving: a dissociation between eye movements and motion perception.

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Spering, Miriam; Pomplun, Marc; Carrasco, Marisa

2011-02-01

Can people react to objects in their visual field that they do not consciously perceive? We investigated how visual perception and motor action respond to moving objects whose visibility is reduced, and we found a dissociation between motion processing for perception and for action. We compared motion perception and eye movements evoked by two orthogonally drifting gratings, each presented separately to a different eye. The strength of each monocular grating was manipulated by inducing adaptation to one grating prior to the presentation of both gratings. Reflexive eye movements tracked the vector average of both gratings (pattern motion) even though perceptual responses followed one motion direction exclusively (component motion). Observers almost never perceived pattern motion. This dissociation implies the existence of visual-motion signals that guide eye movements in the absence of a corresponding conscious percept.

Analysis of Bird Diversity for Supporting Ecotourism Development in Rajegwesi, Meru Betiri National Park

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Hafid Zain Muttaqien

2015-09-01

Full Text Available Potential ecotourism attraction in Rajegwesi Village, Meru Betiri National Park is high due to its high biodiversity, especially bird diversity, in the form of bird watching activity. This study was aimed to determine the species, level of abundance, and diversity of birds found in the Rajegwesi area. Further, this basic information is important to develop the bird watching track at Rajegwesi. We used Quantum-GIS to create the land classification and observation mapping. Bird observation used point count method in the morning and evening with three periods of hour and three repetitions. The study confirmed about 76 species of 39 bird families was found in Rajegwesi. The highest abundance was Pygnonotus goiavier (E:Yellow-vented Bulbul, at the meadows, village, and rehabilitation land. The diversity index showed that the highest diversity was found at the heterogeneous forest (H’ index 3.745, followed by homogenous forest (H’ index 3.150, rehabilitation land (H’ index 2.845, village (H’ index 2.693, paddy fields (H’ index 2.529, and savanna (H’ index 1.880. The observation track was divided into 3 lines based on the bird’s distribution, the Village – Rehabilitation Land track (6.5 Km, Village track (2.3 Km, and Village – Rafflessia Park track (7.5 Km. Total of 25 bird species were found at the Village – Rehabilitation Land track, 22 species were found at the Village track, and 29 bird species were found at the Village – Rafflessia Park track. For the future of ecotourism development through birding development program, there are several issues that should be promoted: promoting birds conservation in the community through bird watching and birds observation competition (Bird race, training on conservation and ecotourism for the community, and strengthening the capacity and capability of Rajegwesi Ecotourism Society (RES on the ecotourism program management. Keywords: bird watching, conservation, ecotourism development, RES

Epidemiologic characterization of Colorado backyard bird flocks.

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Smith, Emily I; Reif, John S; Hill, Ashley E; Slota, Katharine E; Miller, Ryan S; Bjork, Kathe E; Pabilonia, Kristy L

2012-06-01

Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds.

Binocular eye movement control and motion perception: what is being tracked?

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van der Steen, Johannes; Dits, Joyce

2012-10-19

We investigated under what conditions humans can make independent slow phase eye movements. The ability to make independent movements of the two eyes generally is attributed to few specialized lateral eyed animal species, for example chameleons. In our study, we showed that humans also can move the eyes in different directions. To maintain binocular retinal correspondence independent slow phase movements of each eye are produced. We used the scleral search coil method to measure binocular eye movements in response to dichoptically viewed visual stimuli oscillating in orthogonal direction. Correlated stimuli led to orthogonal slow eye movements, while the binocularly perceived motion was the vector sum of the motion presented to each eye. The importance of binocular fusion on independency of the movements of the two eyes was investigated with anti-correlated stimuli. The perceived global motion pattern of anti-correlated dichoptic stimuli was perceived as an oblique oscillatory motion, as well as resulted in a conjugate oblique motion of the eyes. We propose that the ability to make independent slow phase eye movements in humans is used to maintain binocular retinal correspondence. Eye-of-origin and binocular information are used during the processing of binocular visual information, and it is decided at an early stage whether binocular or monocular motion information and independent slow phase eye movements of each eye are produced during binocular tracking.

Environmental drivers of variability in the movement ecology of turkey vultures (Cathartes aura) in North and South America.

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Dodge, Somayeh; Bohrer, Gil; Bildstein, Keith; Davidson, Sarah C; Weinzierl, Rolf; Bechard, Marc J; Barber, David; Kays, Roland; Brandes, David; Han, Jiawei; Wikelski, Martin

2014-01-01

Variation is key to the adaptability of species and their ability to survive changes to the Earth's climate and habitats. Plasticity in movement strategies allows a species to better track spatial dynamics of habitat quality. We describe the mechanisms that shape the movement of a long-distance migrant bird (turkey vulture, Cathartes aura) across two continents using satellite tracking coupled with remote-sensing science. Using nearly 10 years of data from 24 satellite-tracked vultures in four distinct populations, we describe an enormous amount of variation in their movement patterns. We related vulture movement to environmental conditions and found important correlations explaining how far they need to move to find food (indexed by the Normalized Difference Vegetation Index) and how fast they can move based on the prevalence of thermals and temperature. We conclude that the extensive variability in the movement ecology of turkey vultures, facilitated by their energetically efficient thermal soaring, suggests that this species is likely to do well across periods of modest climate change. The large scale and sample sizes needed for such analysis in a widespread migrant emphasizes the need for integrated and collaborative efforts to obtain tracking data and for policies, tools and open datasets to encourage such collaborations and data sharing.

Tracking socioeconomic vulnerability using network analysis: insights from an avian influenza outbreak in an ostrich production network.

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Christine Moore

Full Text Available BACKGROUND: The focus of management in many complex systems is shifting towards facilitation, adaptation, building resilience, and reducing vulnerability. Resilience management requires the development and application of general heuristics and methods for tracking changes in both resilience and vulnerability. We explored the emergence of vulnerability in the South African domestic ostrich industry, an animal production system which typically involves 3-4 movements of each bird during its lifetime. This system has experienced several disease outbreaks, and the aim of this study was to investigate whether these movements have contributed to the vulnerability of this system to large disease outbreaks. METHODOLOGY/PRINCIPAL FINDINGS: The ostrich production system requires numerous movements of birds between different farm types associated with growth (i.e. Hatchery to juvenile rearing farm to adult rearing farm. We used 5 years of movement records between 2005 and 2011 prior to an outbreak of Highly Pathogenic Avian Influenza (H5N2. These data were analyzed using a network analysis in which the farms were represented as nodes and the movements of birds as links. We tested the hypothesis that increasing economic efficiency in the domestic ostrich industry in South Africa made the system more vulnerable to outbreak of Highly Pathogenic Avian Influenza (H5N2. Our results indicated that as time progressed, the network became increasingly vulnerable to pathogen outbreaks. The farms that became infected during the outbreak displayed network qualities, such as significantly higher connectivity and centrality, which predisposed them to be more vulnerable to disease outbreak. CONCLUSIONS/SIGNIFICANCE: Taken in the context of previous research, our results provide strong support for the application of network analysis to track vulnerability, while also providing useful practical implications for system monitoring and management.

Assessment of Motor Control during Three-Dimensional Movements Tracking with Position-Varying Gravity Compensation

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Yao Huang

2017-05-01

Full Text Available Active movements are important in the rehabilitation training for patients with neurological motor disorders, while weight of upper limb impedes movements due to muscles weakness. The objective of this study is to develop a position-varying gravity compensation strategy for a cable-based rehabilitation robot. The control strategy can estimate real-time gravity torque according to position feedback. Then, the performance of this control strategy was compared with the other two kinds of gravity compensation strategies (i.e., without compensation and with fixed compensation during movements tracking. Seven healthy subjects were invited to conduct tracking tasks along four different directions (i.e., upward, forward, leftward, and rightward. The performance of movements with different compensation strategies was compared in terms of root mean square error (RMSE between target and actual moving trajectories, normalized jerk score (NJS, mean velocity ratio (MVR of main motion direction, and the activation of six muscles. The results showed that there were significant effects in control strategies in all four directions with the RMSE and NJS values in the following order: without compensation > fixed compensation > position-varying compensation and MVR values in the following order: without compensation < fixed compensation < position-varying compensation (p < 0.05. Comparing with movements without compensation in all four directions, the activation of muscles during movements with position-varying compensation showed significant reductions, except the activations of triceps and in forward and leftward movements, the activations of upper trapezius and middle parts of deltoid in upward movements and the activations of posterior parts of deltoid in all four directions (p < 0.05. Therefore, with position-varying gravity compensation, the upper limb cable-based rehabilitation robotic system might assist subjects to perform movements with higher quality and

Movements and landscape use of Eastern Imperial Eagles Aquila heliaca in Central Asia

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Poessel, Sharon; Bragin, Evgeny A.; Sharpe, Peter B.; Garcelon, David K.; Bartoszuk, Kordian; Katzner, Todd E.

2018-01-01

Capsule: We describe ecological factors associated with movements of a globally declining raptor species, the Eastern Imperial Eagle Aquila heliaca.Aims: To describe the movements, habitat associations and resource selection of Eastern Imperial Eagles marked in Central Asia.Methods: We used global positioning system (GPS) data sent via satellite telemetry devices deployed on Eastern Imperial Eagles captured in Kazakhstan to calculate distances travelled and to associate habitat and weather variables with eagle locations collected throughout the annual cycle. We also used resource selection models to evaluate habitat use of tracked birds during autumn migration. Separately, we used wing-tagging recovery data to broaden our understanding of wintering locations of eagles.Results: Eagles tagged in Kazakhstan wintered in most countries on the Arabian Peninsula, as well as Iran and India. The adult eagle we tracked travelled more efficiently than did the four pre-adults. During autumn migration, telemetered eagles used a mixture of vegetation types, but during winter and summer, they primarily used bare and sparsely vegetated areas. Finally, telemetered birds used orographic updrafts to subsidize their autumn migration flight, but they relied on thermal updrafts during spring migration.Conclusion: Our study is the first to use GPS telemetry to describe year-round movements and habitat associations of Eastern Imperial Eagles in Central Asia. Our findings provide insight into the ecology of this vulnerable raptor species that can contribute to conservation efforts on its behalf.

Factors influencing the movement biology of migrant songbirds confronted with an ecological barrier

Science.gov (United States)

Smolinsky, J. A.; Diehl, Robert H.; Radzio, T. A.; Delaney, D. K.; Moore, F. R

2013-01-01

Whether or not a migratory songbird embarks on a long-distance flight across an ecological barrier is likely a response to a number of endogenous and exogenous factors. During autumn 2008 and 2009, we used automated radio tracking to investigate how energetic condition, age, and weather influenced the departure timing and direction of Swainson’s thrushes (Catharus ustulatus) during migratory stopover along the northern coast of the Gulf of Mexico. Most birds left within 1 h after sunset on the evening following capture. Those birds that departed later on the first night or remained longer than 1 day were lean. Birds that carried fat loads sufficient to cross the Gulf of Mexico generally departed in a seasonally appropriate southerly direction, whereas lean birds nearly always flew inland in a northerly direction. We did not detect an effect of age or weather on departures. The decision by lean birds to reorient movement inland may reflect the suitability of the coastal stopover site for deposition of fuel stores and the motivation to seek food among more extensive forested habitat away from the barrier.

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

Science.gov (United States)

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...

Effects of geolocators on hatching success, return rates, breeding movements, and change in body mass in 16 species of Arctic-breeding shorebirds

NARCIS (Netherlands)

Weiser, Emily L; Lanctot, Richard B.; Brown, Stephen C; Alves, José A.; Battley, Phil; Bentzen, Rebecca; Bêty, Joël; Bishop, Mary Anne; Boldenow, Megan; Bollache, Loïc; Casler, Bruce; Christie, Maureen; T. Coleman, Jonathan; Conklin, Jesse; B. English, Willow; Gates, H. River; Gilg, Olivier; Giroux, Marie-Andrée; Gosbell, Ken; Hassell, Chris J.; Helmericks, Jim; Johnson, Andrew; Katrínardóttir, Borgný; Koivula, Kari; Kwon, Eunbi; Lamarre, Jean-Francois; Lang, Johannes; Lank, David B.; Lecomte, Nicolas; Liebezeit, Joe; Loverti, Vanessa; McKinnon, Laura; Minton, Clive D. T.; Mizrahi, David; Minton, Clive D. T.; Nol, Erica; Pakanen, Veli-Matti; Perz, Johanna; Porter, Ron; Rausch, Jennie; Reneerkens, Jeroen; Rönkä, Nelli; Saalfeld, Sarah; Senner, Nathan; Sittler, Benoit; Smith, Paul A.; Sowl, Kristine; Taylor, Audrey; Ward, David H.; Yezerinac, Stephen; Sandercock, Brett K.

2016-01-01

Background: Geolocators are useful for tracking movements of long-distance migrants, but potential negative effects on birds have not been well studied. We tested for effects of geolocators (0.8–2.0 g total, representing 0.1–3.9 % of mean body mass) on 16 species of migratory shorebirds, including

Eye movements in Multiple Object Tracking systematically lagging behind the scene content

Czech Academy of Sciences Publication Activity Database

Lukavský, Jiří

2013-01-01

Roč. 42, Suppl (2013), s. 42-43 ISSN 0301-0066. [36th European Conference on Visual Perception . 25.08.2013.-29.08.2013, Brémy] R&D Projects: GA ČR GA13-28709S Institutional support: RVO:68081740 Keywords : eye movements * attention * multiple object tracking Subject RIV: AN - Psychology http://www. perception web.com/abstract.cgi?id=v130146

Internal and external factors shaping movement and distributions of trans-Saharan migrants

DEFF Research Database (Denmark)

Vega, Marta Lomas

and thrush nightingales Luscinia luscinia. It also looks at how the migration routes can be affected by future climate change. Results indicate that insectivore long-distance migrants temporally adjust migration schedules with seasonal surplus of vegetation greenness during the annual cycle. Climate......he migratory programme provides birds with the capacity to seasonally migrate thousands of kilometres during their annual breeding cycle. This programme is governed by endogenous, and environmentally-shaped, exogenous, processes. Using a diverse set of tracking methods, this thesis investigates...... (vectororientation) and possibly includes a simple navigation capability that enables juveniles to compensate for crosswind en route, but not to compensate for experimental displacement. To study exogenous influence, paper III and IV investigate how environmental factors shape movements of migratory birds at local...

High-Speed Surface Reconstruction of Flying Birds Using Structured Light

Science.gov (United States)

Deetjen, Marc; Lentink, David

2017-11-01

Birds fly effectively through complex environments, and in order to understand the strategies that enable them to do so, we need to determine the shape and movement of their wings. Previous studies show that even small perturbations in wing shape have dramatic aerodynamic effects, but these shape changes have not been quantified automatically at high temporal and spatial resolutions. Hence, we developed a custom 3D surface mapping method which uses a high-speed camera to view a grid of stripes projected onto a flying bird. Because the light is binary rather than grayscale, and each frame is separately analyzed, this method can function at any frame rate with sufficient light. The method is automated, non-invasive, and able to measure a volume by simultaneously reconstructing from multiple views. We use this technique to reconstruct the 3D shape of the surface of a parrotlet during flapping flight at 3200 fps. We then analyze key dynamic parameters such as wing twist and angle of attack, and compute aerodynamic parameters such as lift and drag. While this novel system is designed to quantify bird wing shape and motion, it is adaptable for tracking other objects such as quickly deforming fish, especially those which are difficult to reconstruct using other 3D tracking methods. The presenter needs to leave by 3 pm on the final day of the conference (11/21) in order to make his flight. Please account for this in the scheduling if possible by scheduling the presentation earlier in the day or a different day.

Changes in hydrogen isotope ratios in sequential plumage stages: an implication for the creation of isotope-base maps for tracking migratory birds.

Science.gov (United States)

Duxbury, J M; Holroyd, G L; Muehlenbachs, K

2003-09-01

Accurate reference maps are important in the use of stable-isotopes to track the movements of migratory birds. Reference maps created by the analysis of samples collected from young at the nest site are more accurate than simply referring to naturally occurring patterns of hydrogen isotope ratios created by precipitation cycles. Ratios of hydrogen isotopes in the nutrients incorporated early in the development of young birds can be derived from endogenous, maternal sources. Base-maps should be created with the analysis of tissue samples from hatchlings after local the isotopic signature of exogenous nutrients is dominant. Migratory species such as Peregrine Falcons are known to use endogenous sources in the creation of their eggs, therefore knowledge of what plumage stage best represents the local hydrogen ratios would assist in the planning of nest visits. We conducted diet manipulation experiments involving Japanese Quail and Peregrine Falcons to determine the plumage stage when hydrogen isotope ratios were indicative of a switch in their food source. The natal down of both the quail and falcons reflected the diet of breeding adult females. The hydrogen isotope ratios of a new food source were dominant in the juvenile down of the young falcons, although a further shift was detected in the final juvenile plumage. The juvenile plumage is grown during weeks 3-4 after hatch on Peregrine Falcons. Nest visits for the purpose of collecting feathers for isotope-base-map creation should be made around 4 weeks after the presumed hatch of the young falcons.

Lack of observed movement response to lead exposure of California condors

Science.gov (United States)

Poessel, Sharon; Brandt, Joseph; Uyeda, Linda; Astell, Molly; Katzner, Todd E.

2018-01-01

Lead poisoning is an important conservation concern for wildlife, and scavenging birds are especially at risk from consumption of carcasses of animals killed with lead ammunition. Because current methods to identify lead exposure require animal capture and blood collection, management would benefit from the development of a less costly and noninvasive behavioral test for illness in wild animals. We attempted to design such a test to identify lead exposure in California condors (Gymnogyps californianus) that we tracked with global positioning system (GPS) telemetry in southern California, USA, 2013–2016. We measured blood-lead concentrations in tracked birds and expected that flight behavior would be influenced by lead exposure; thus, we measured the effect of blood-lead concentrations on 2 different types of movement rates and on the proportion of time condors spent in flight. We found no effect of lead exposure on any of these 3 behavioral metrics. Our work suggests that the measurements we took of flight behaviors were not a useful tool in predicting lead exposure in the mildly to moderately exposed birds we studied. Wild birds are effective at hiding illness, especially condors who have a strong social hierarchy in which showing weakness is a disadvantage. However, focusing on behaviors other than flight, expanding the sample studied to include birds with a wider range of lead concentration values, or analyzing tissues such as feathers (rather than, or in addition to, blood) may be more useful for identification of lead exposure and other diseases that may limit wildlife populations. © 2017 This article is a U.S. Government work and is in the public domain in the USA.

Do Birds Avoid Railroads as Has Been Found for Roads?

Science.gov (United States)

Wiącek, Jarosław; Polak, Marcin; Filipiuk, Maciej; Kucharczyk, Marek; Bohatkiewicz, Janusz

2015-09-01

The construction of railway lines usually has a negative effect on the natural environment: habitats are destroyed, collisions with trains cause deaths, and the noise and vibrations associated with rail traffic disturb the lives of animals. Cases are known, however, where the opposite holds true: a railway line has a positive effect on the fauna in its vicinity. In this study, we attempted to define the influence of a busy railway line on a breeding community of woodland birds. Birds were counted using the point method at 45 observation points located at three different distances (30, 280, 530 m) from the tracks. At each point, we determined the habitat parameters and the intensity of noise. In total, 791 individual birds of 42 species were recorded on the study plot. Even though the noise level fell distinctly with increasing distance from the tracks, the abundance of birds and the number of species were the highest near the railway line. Moreover, insectivorous species displayed a clear preference for the vicinity of the line. The noise from the trains did not adversely affect the birds on the study plot. The environmental conditions created by the edge effect meant that the birds preferred the neighborhood of the tracks: the more diverse habitats near the tracks supplied attractive nesting and foraging niches for many species of birds. Trains passing at clear intervals acted as point sources of noise and did not elicit any negative reactions on the part of the birds; this stands in contrast to busy roads, where the almost continuous flow of traffic in practice constitutes a linear source of noise.

Movements of Birds and Avian Influenza from Asia into Alaska

OpenAIRE

Winker, Kevin; McCracken, Kevin G.; Gibson, Daniel D.; Pruett, Christin L.; Meier, Rose; Huettmann, Falk; Wege, Michael; Kulikova, Irina V.; Zhuravlev, Yuri N.; Perdue, Michael L.; Spackman, Erica; Suarez, David L.; Swayne, David E.

2007-01-01

Asian-origin avian influenza (AI) viruses are spread in part by migratory birds. In Alaska, diverse avian hosts from Asia and the Americas overlap in a region of intercontinental avifaunal mixing. This region is hypothesized to be a zone of Asia-to-America virus transfer because birds there can mingle in waters contaminated by wild-bird?origin AI viruses. Our 7 years of AI virus surveillance among waterfowl and shorebirds in this region (1998?2004; 8,254 samples) showed remarkably low infecti...

Mouse cursor movement and eye tracking data as an indicator of pathologists′ attention when viewing digital whole slide images

Directory of Open Access Journals (Sweden)

Vignesh Raghunath

2012-01-01

Full Text Available Context: Digital pathology has the potential to dramatically alter the way pathologists work, yet little is known about pathologists′ viewing behavior while interpreting digital whole slide images. While tracking pathologist eye movements when viewing digital slides may be the most direct method of capturing pathologists′ viewing strategies, this technique is cumbersome and technically challenging to use in remote settings. Tracking pathologist mouse cursor movements may serve as a practical method of studying digital slide interpretation, and mouse cursor data may illuminate pathologists′ viewing strategies and time expenditures in their interpretive workflow. Aims: To evaluate the utility of mouse cursor movement data, in addition to eye-tracking data, in studying pathologists′ attention and viewing behavior. Settings and Design: Pathologists (N = 7 viewed 10 digital whole slide images of breast tissue that were selected using a random stratified sampling technique to include a range of breast pathology diagnoses (benign/atypia, carcinoma in situ, and invasive breast cancer. A panel of three expert breast pathologists established a consensus diagnosis for each case using a modified Delphi approach. Materials and Methods: Participants′ foveal vision was tracked using SensoMotoric Instruments RED 60 Hz eye-tracking system. Mouse cursor movement was tracked using a custom MATLAB script. Statistical Analysis Used: Data on eye-gaze and mouse cursor position were gathered at fixed intervals and analyzed using distance comparisons and regression analyses by slide diagnosis and pathologist expertise. Pathologists′ accuracy (defined as percent agreement with the expert consensus diagnoses and efficiency (accuracy and speed were also analyzed. Results: Mean viewing time per slide was 75.2 seconds (SD = 38.42. Accuracy (percent agreement with expert consensus by diagnosis type was: 83% (benign/atypia; 48% (carcinoma in situ; and 93% (invasive

Mouse cursor movement and eye tracking data as an indicator of pathologists’ attention when viewing digital whole slide images

Science.gov (United States)

Raghunath, Vignesh; Braxton, Melissa O.; Gagnon, Stephanie A.; Brunyé, Tad T.; Allison, Kimberly H.; Reisch, Lisa M.; Weaver, Donald L.; Elmore, Joann G.; Shapiro, Linda G.

2012-01-01

Context: Digital pathology has the potential to dramatically alter the way pathologists work, yet little is known about pathologists’ viewing behavior while interpreting digital whole slide images. While tracking pathologist eye movements when viewing digital slides may be the most direct method of capturing pathologists’ viewing strategies, this technique is cumbersome and technically challenging to use in remote settings. Tracking pathologist mouse cursor movements may serve as a practical method of studying digital slide interpretation, and mouse cursor data may illuminate pathologists’ viewing strategies and time expenditures in their interpretive workflow. Aims: To evaluate the utility of mouse cursor movement data, in addition to eye-tracking data, in studying pathologists’ attention and viewing behavior. Settings and Design: Pathologists (N = 7) viewed 10 digital whole slide images of breast tissue that were selected using a random stratified sampling technique to include a range of breast pathology diagnoses (benign/atypia, carcinoma in situ, and invasive breast cancer). A panel of three expert breast pathologists established a consensus diagnosis for each case using a modified Delphi approach. Materials and Methods: Participants’ foveal vision was tracked using SensoMotoric Instruments RED 60 Hz eye-tracking system. Mouse cursor movement was tracked using a custom MATLAB script. Statistical Analysis Used: Data on eye-gaze and mouse cursor position were gathered at fixed intervals and analyzed using distance comparisons and regression analyses by slide diagnosis and pathologist expertise. Pathologists’ accuracy (defined as percent agreement with the expert consensus diagnoses) and efficiency (accuracy and speed) were also analyzed. Results: Mean viewing time per slide was 75.2 seconds (SD = 38.42). Accuracy (percent agreement with expert consensus) by diagnosis type was: 83% (benign/atypia); 48% (carcinoma in situ); and 93% (invasive). Spatial

Single bacteria movement tracking by online microscopy--a proof of concept study.

Directory of Open Access Journals (Sweden)

Andreas Ziegler

Full Text Available In this technical report we demonstrate a low-cost online unit allowing movement tracking of flagellated bacteria on a single-cell level during fermentation processes. The system's ability to distinguish different metabolic states (viability of bacteria by movement velocity was investigated. A flow-through cuvette with automatically adjustable layer thickness was developed. The cuvette can be used with most commercially available laboratory microscopes equipped with 40× amplification and a digital camera. In addition, an automated sample preparation unit and a software module was developed measuring size, moved distance, and speed of bacteria. In a proof of principle study the movement velocities of Bacillus amyloliquefaciens FZB42 during three batch fermentation processes were investigated. In this process the bacteria went through different metabolic states, vegetative growth, diauxic shift, vegetative growth after diauxic shift, and sporulation. It was shown that the movement velocities during the different metabolic states significantly differ from each other. Therefore, the described setup has the potential to be used as a bacteria viability monitoring tool. In contrast to some other techniques, such as electro-optical techniques, this method can even be used in turbid production media.

Molecular motors that digest their track to rectify Brownian motion: processive movement of exonuclease enzymes.

Science.gov (United States)

Xie, Ping

2009-09-16

A general model is presented for the processive movement of molecular motors such as λ-exonuclease, RecJ and exonuclease I that use digestion of a DNA track to rectify Brownian motion along this track. Using this model, the translocation dynamics of these molecular motors is studied. The sequence-dependent pausing of λ-exonuclease, which results from a site-specific high affinity DNA interaction, is also studied. The theoretical results are consistent with available experimental data. Moreover, the model is used to predict the lifetime distribution and force dependence of these paused states.

Molecular motors that digest their track to rectify Brownian motion: processive movement of exonuclease enzymes

International Nuclear Information System (INIS)

Xie Ping

2009-01-01

A general model is presented for the processive movement of molecular motors such as λ-exonuclease, RecJ and exonuclease I that use digestion of a DNA track to rectify Brownian motion along this track. Using this model, the translocation dynamics of these molecular motors is studied. The sequence-dependent pausing of λ-exonuclease, which results from a site-specific high affinity DNA interaction, is also studied. The theoretical results are consistent with available experimental data. Moreover, the model is used to predict the lifetime distribution and force dependence of these paused states.

SU-E-T-603: Analysis of Optical Tracked Head Inter-Fraction Movements Within Masks to Access Intracranial Immobilization Techniques in Proton Therapy

International Nuclear Information System (INIS)

Hsi, W; Zeidan, O

2014-01-01

Purpose: We present a quantitative methodology utilizing an optical tracking system for monitoring head inter-fraction movements within brain masks to assess the effectiveness of two intracranial immobilization techniques. Methods and Materials: A 3-point-tracking method was developed to measure the mask location for a treatment field at each fraction. Measured displacement of mask location to its location at first fraction is equivalent to the head movement within the mask. Head movements for each of treatment fields were measured over about 10 fractions at each patient for seven patients; five treated in supine and two treated in prone. The Q-fix Base-of-Skull head frame was used in supine while the CIVCO uni-frame baseplate was used in prone. Displacements of recoded couch position of each field post imaging at each fraction were extracted for those seven patients. Standard deviation (S.D.) of head movements and couch displacements was scored for statistical analysis. Results: The accuracy of 3PtTrack method was within 1.0 mm by phantom measurements. Patterns of head movement and couch displacement were similar for patients treated in either supine or prone. In superior-inferior direction, mean value of scored standard deviations over seven patients were 1.6 mm and 3.4 mm for the head movement and the couch displacement, respectively. The result indicated that the head movement combined with a loose fixation between the mask-to-head frame results large couch displacements for each patient, and also large variation between patients. However, the head movement is the main cause for the couch displacement with similar magnitude of around 1.0 mm in anterior-posterior and lateral directions. Conclusions: Optical-tracking methodology independently quantifying head movements could improve immobilization devices by correctly acting on causes for head motions within mask. A confidence in the quality of intracranial immobilization techniques could be more efficient by

Colonic movements in healthy subjects as monitored by a Magnet Tracking System.

Science.gov (United States)

Hiroz, P; Schlageter, V; Givel, J-C; Kucera, P

2009-08-01

The Magnet Tracking System (MTS) is a minimally-invasive technique of continuous evaluation of gastrointestinal motility. In this study, MTS was used to analyse colonic propulsive dynamics and compare the transit of a magnetic pill with that of standard radio-opaque markers. MTS monitors the progress in real time of a magnetic pill through the gut. Ten men and 10 women with regular daily bowel movements swallowed this pill and 10 radio-opaque markers at 8 pm. Five hours of recordings were conducted during 2 following mornings. Origin, direction, amplitude and velocity of movements were analysed relative to space-time plots of the pill trajectory. Abdominal radiographs were taken to compare the progress of both pill and markers. The magnetic pill lay idle for 90% of its sojourn in the colon; its total retrograde displacement accounted for only 20% of its overall movement. Analysis of these movements showed a bimodal distribution of velocities: around 1.5 and 50 cm min(-1), the latter being responsible for 2/3 of distance traversed. There were more movements overall and more mass movements in males. Net hourly forward progress was greater in the left than right colon, and greater in males. The position of the magnetic pill correlated well with the advancement of markers. MTS showed patterns and propulsion dynamics of colonic segments with as yet unmet precision. Detailed analysis of slow and fast patterns of colonic progress makes it possible to specify the motility of colonic segments, and any variability in gender. Such analysis opens up promising avenues in studies of motility disorders.

North Atlantic migratory bird flyways provide routes for intercontinental movement of avian influenza viruses

Science.gov (United States)

Dusek, Robert J.; Hallgrimsson, Gunnar T.; Ip, Hon S.; Jónsson, Jón E.; Sreevatsan, Srinand; Nashold, Sean W.; TeSlaa, Joshua L.; Enomoto, Shinichiro; Halpin, Rebecca A.; Lin, Xudong; Federova, Nadia; Stockwell, Timothy B.; Dugan, Vivien G.; Wentworth, David E.; Hall, Jeffrey S.

2014-01-01

Avian influenza virus (AIV) in wild birds has been of increasing interest over the last decade due to the emergence of AIVs that cause significant disease and mortality in both poultry and humans. While research clearly demonstrates that AIVs can move across the Pacific or Atlantic Ocean, there has been no data to support the mechanism of how this occurs. In spring and autumn of 2010 and autumn of 2011 we obtained cloacal swab samples from 1078 waterfowl, gulls, and shorebirds of various species in southwest and west Iceland and tested them for AIV. From these, we isolated and fully sequenced the genomes of 29 AIVs from wild caught gulls (Charadriiformes) and waterfowl (Anseriformes) in Iceland. We detected viruses that were entirely (8 of 8 genomic segments) of American lineage, viruses that were entirely of Eurasian lineage, and viruses with mixed American-Eurasian lineage. Prior to this work only 2 AIVs had been reported from wild birds in Iceland and only the sequence from one segment was available in GenBank. This is the first report of finding AIVs of entirely American lineage and Eurasian lineage, as well as reassortant viruses, together in the same geographic location. Our study demonstrates the importance of the North Atlantic as a corridor for the movement of AIVs between Europe and North America.

Using strategic movement to calibrate a neural compass: a spiking network for tracking head direction in rats and robots.

Directory of Open Access Journals (Sweden)

Peter Stratton

Full Text Available The head direction (HD system in mammals contains neurons that fire to represent the direction the animal is facing in its environment. The ability of these cells to reliably track head direction even after the removal of external sensory cues implies that the HD system is calibrated to function effectively using just internal (proprioceptive and vestibular inputs. Rat pups and other infant mammals display stereotypical warm-up movements prior to locomotion in novel environments, and similar warm-up movements are seen in adult mammals with certain brain lesion-induced motor impairments. In this study we propose that synaptic learning mechanisms, in conjunction with appropriate movement strategies based on warm-up movements, can calibrate the HD system so that it functions effectively even in darkness. To examine the link between physical embodiment and neural control, and to determine that the system is robust to real-world phenomena, we implemented the synaptic mechanisms in a spiking neural network and tested it on a mobile robot platform. Results show that the combination of the synaptic learning mechanisms and warm-up movements are able to reliably calibrate the HD system so that it accurately tracks real-world head direction, and that calibration breaks down in systematic ways if certain movements are omitted. This work confirms that targeted, embodied behaviour can be used to calibrate neural systems, demonstrates that 'grounding' of modelled biological processes in the real world can reveal underlying functional principles (supporting the importance of robotics to biology, and proposes a functional role for stereotypical behaviours seen in infant mammals and those animals with certain motor deficits. We conjecture that these calibration principles may extend to the calibration of other neural systems involved in motion tracking and the representation of space, such as grid cells in entorhinal cortex.

Using strategic movement to calibrate a neural compass: a spiking network for tracking head direction in rats and robots.

Science.gov (United States)

Stratton, Peter; Milford, Michael; Wyeth, Gordon; Wiles, Janet

2011-01-01

The head direction (HD) system in mammals contains neurons that fire to represent the direction the animal is facing in its environment. The ability of these cells to reliably track head direction even after the removal of external sensory cues implies that the HD system is calibrated to function effectively using just internal (proprioceptive and vestibular) inputs. Rat pups and other infant mammals display stereotypical warm-up movements prior to locomotion in novel environments, and similar warm-up movements are seen in adult mammals with certain brain lesion-induced motor impairments. In this study we propose that synaptic learning mechanisms, in conjunction with appropriate movement strategies based on warm-up movements, can calibrate the HD system so that it functions effectively even in darkness. To examine the link between physical embodiment and neural control, and to determine that the system is robust to real-world phenomena, we implemented the synaptic mechanisms in a spiking neural network and tested it on a mobile robot platform. Results show that the combination of the synaptic learning mechanisms and warm-up movements are able to reliably calibrate the HD system so that it accurately tracks real-world head direction, and that calibration breaks down in systematic ways if certain movements are omitted. This work confirms that targeted, embodied behaviour can be used to calibrate neural systems, demonstrates that 'grounding' of modelled biological processes in the real world can reveal underlying functional principles (supporting the importance of robotics to biology), and proposes a functional role for stereotypical behaviours seen in infant mammals and those animals with certain motor deficits. We conjecture that these calibration principles may extend to the calibration of other neural systems involved in motion tracking and the representation of space, such as grid cells in entorhinal cortex.

Functional connectivity experiments reflect routine movement behavior of a tropical hummingbird species.

Science.gov (United States)

Volpe, Noelia L; Hadley, Adam S; Robinson, W Douglas; Betts, Matthew G

Translocation experiments, in which researchers displace animals and then monitor their movements to return home, are commonly used as tools to assess functional connectivity of fragmented landscapes. Such experiments are purported to have important advantages of being time efficient and of standardizing “motivation” to move across individuals. Yet, we lack tests of whether movement behavior of translocated birds reflects natural behavior of unmanipulated birds. We compared the routine movement behavior of a tropical hummingbird, the Green Hermit (Phaethornis guy), to that of experimentally translocated individuals. We tested for differences in site selection patterns during movement at two spatial scales (point and path levels). We also compared movement rates between treatments. Behaviors documented during translocation experiments reflected those observed during routine movements. At the point level, both translocated and non-translocated birds showed similar levels of preference for mature tropical forest. At the path level, step selection functions showed both translocated and non-translocated hummingbirds avoiding movement across non-forested matrix and selecting streams as movement corridors. Movement rates were generally higher during translocation experiments. However, the negative influence of forest cover on movement rates was proportionately similar in translocation and routine movement treatments. We report the first evidence showing that movement behavior of birds during translocation experiments is similar to their natural movement behavior. Therefore, translocation experiments may be reliable tools to address effects of landscape structure on animal movement. We observed consistent selection of landscape elements between translocated and non-translocated birds, indicating that both routine and translocation movement studies lead to similar conclusions regarding the effect of landscape structure and forest composition on functional connectivity

Avian Alert - a bird migration early warning system

OpenAIRE

van Gasteren, H.; Shamoun-Baranes, J.; Ginati, A.; Garofalo, G.

2008-01-01

Every year billions of birds migrate from breeding areas to their wintering ranges, some travelling over 10,000 km. Stakeholders interested in aviation flight safety, spread of disease, conservation, education, urban planning, meteorology, wind turbines and bird migration ecology are interested in information on bird movements. Collecting and disseminating useful information about such mobile creatures exhibiting diverse behaviour is no simple task. However, ESA’s Integrated Application Promo...

Aerodynamics of bird flight

Directory of Open Access Journals (Sweden)

Dvořák Rudolf

2016-01-01

Full Text Available Unlike airplanes birds must have either flapping or oscillating wings (the hummingbird. Only such wings can produce both lift and thrust – two sine qua non attributes of flying.The bird wings have several possibilities how to obtain the same functions as airplane wings. All are realized by the system of flight feathers. Birds have also the capabilities of adjusting the shape of the wing according to what the immediate flight situation demands, as well as of responding almost immediately to conditions the flow environment dictates, such as wind gusts, object avoidance, target tracking, etc. In bird aerodynamics also the tail plays an important role. To fly, wings impart downward momentum to the surrounding air and obtain lift by reaction. How this is achieved under various flight situations (cruise flight, hovering, landing, etc., and what the role is of the wing-generated vortices in producing lift and thrust is discussed.The issue of studying bird flight experimentally from in vivo or in vitro experiments is also briefly discussed.

Tracking domestic ducks: A novel approach for documenting poultry market chains in the context of avian influenza transmission

Science.gov (United States)

Choi, Chang-Yong; Takekawa, John Y.; Xiong, Yue; Wikelski, Martin; Heine, George; Prosser, Diann J.; Newman, Scott H.; Edwards, John; Guo, Fusheng; Xiao, Xiangming

2016-01-01

Agro-ecological conditions associated with the spread and persistence of highly pathogenic avian influenza (HPAI) are not well understood, but the trade of live poultry is suspected to be a major pathway. Although market chains of live bird trade have been studied through indirect means including interviews and questionnaires, direct methods have not been used to identify movements of individual poultry. To bridge the knowledge gap on quantitative movement and transportation of poultry, we introduced a novel approach for applying telemetry to document domestic duck movements from source farms at Poyang Lake, China. We deployed recently developed transmitters that record Global Positioning System (GPS) locations and send them through the Groupe Spécial Mobile (GSM) cellular telephone system. For the first time, we were able to track individually marked ducks from 3 to 396 km from their origin to other farms, distribution facilities, or live bird markets. Our proof of concept test showed that the use of GPS-GSM transmitters may provide direct, quantitative information to document the movement of poultry and reveal their market chains. Our findings provide an initial indication of the complexity of source-market network connectivity and highlight the great potential for future telemetry studies in poultry network analyses.

A neural tracking and motor control approach to improve rehabilitation of upper limb movements

Directory of Open Access Journals (Sweden)

Schmid Maurizio

2008-02-01

Full Text Available Abstract Background Restoration of upper limb movements in subjects recovering from stroke is an essential keystone in rehabilitative practices. Rehabilitation of arm movements, in fact, is usually a far more difficult one as compared to that of lower extremities. For these reasons, researchers are developing new methods and technologies so that the rehabilitative process could be more accurate, rapid and easily accepted by the patient. This paper introduces the proof of concept for a new non-invasive FES-assisted rehabilitation system for the upper limb, called smartFES (sFES, where the electrical stimulation is controlled by a biologically inspired neural inverse dynamics model, fed by the kinematic information associated with the execution of a planar goal-oriented movement. More specifically, this work details two steps of the proposed system: an ad hoc markerless motion analysis algorithm for the estimation of kinematics, and a neural controller that drives a synthetic arm. The vision of the entire system is to acquire kinematics from the analysis of video sequences during planar arm movements and to use it together with a neural inverse dynamics model able to provide the patient with the electrical stimulation patterns needed to perform the movement with the assisted limb. Methods The markerless motion tracking system aims at localizing and monitoring the arm movement by tracking its silhouette. It uses a specifically designed motion estimation method, that we named Neural Snakes, which predicts the arm contour deformation as a first step for a silhouette extraction algorithm. The starting and ending points of the arm movement feed an Artificial Neural Controller, enclosing the muscular Hill's model, which solves the inverse dynamics to obtain the FES patterns needed to move a simulated arm from the starting point to the desired point. Both position error with respect to the requested arm trajectory and comparison between curvature factors

Webcams for Bird Detection and Monitoring: A Demonstration Study

Directory of Open Access Journals (Sweden)

Willem W. Verstraeten

2010-04-01

Full Text Available Better insights into bird migration can be a tool for assessing the spread of avian borne infections or ecological/climatologic issues reflected in deviating migration patterns. This paper evaluates whether low budget permanent cameras such as webcams can offer a valuable contribution to the reporting of migratory birds. An experimental design was set up to study the detection capability using objects of different size, color and velocity. The results of the experiment revealed the minimum size, maximum velocity and contrast of the objects required for detection by a standard webcam. Furthermore, a modular processing scheme was proposed to track and follow migratory birds in webcam recordings. Techniques such as motion detection by background subtraction, stereo vision and lens distortion were combined to form the foundation of the bird tracking algorithm. Additional research to integrate webcam networks, however, is needed and future research should enforce the potential of the processing scheme by exploring and testing alternatives of each individual module or processing step.

Eye tracking detects disconjugate eye movements associated with structural traumatic brain injury and concussion.

Science.gov (United States)

Samadani, Uzma; Ritlop, Robert; Reyes, Marleen; Nehrbass, Elena; Li, Meng; Lamm, Elizabeth; Schneider, Julia; Shimunov, David; Sava, Maria; Kolecki, Radek; Burris, Paige; Altomare, Lindsey; Mehmood, Talha; Smith, Theodore; Huang, Jason H; McStay, Christopher; Todd, S Rob; Qian, Meng; Kondziolka, Douglas; Wall, Stephen; Huang, Paul

2015-04-15

Disconjugate eye movements have been associated with traumatic brain injury since ancient times. Ocular motility dysfunction may be present in up to 90% of patients with concussion or blast injury. We developed an algorithm for eye tracking in which the Cartesian coordinates of the right and left pupils are tracked over 200 sec and compared to each other as a subject watches a short film clip moving inside an aperture on a computer screen. We prospectively eye tracked 64 normal healthy noninjured control subjects and compared findings to 75 trauma subjects with either a positive head computed tomography (CT) scan (n=13), negative head CT (n=39), or nonhead injury (n=23) to determine whether eye tracking would reveal the disconjugate gaze associated with both structural brain injury and concussion. Tracking metrics were then correlated to the clinical concussion measure Sport Concussion Assessment Tool 3 (SCAT3) in trauma patients. Five out of five measures of horizontal disconjugacy were increased in positive and negative head CT patients relative to noninjured control subjects. Only one of five vertical disconjugacy measures was significantly increased in brain-injured patients relative to controls. Linear regression analysis of all 75 trauma patients demonstrated that three metrics for horizontal disconjugacy negatively correlated with SCAT3 symptom severity score and positively correlated with total Standardized Assessment of Concussion score. Abnormal eye-tracking metrics improved over time toward baseline in brain-injured subjects observed in follow-up. Eye tracking may help quantify the severity of ocular motility disruption associated with concussion and structural brain injury.

To migrate, stay put, or wander? Varied movement strategies in bald eagles (Haliaeetus leucocephalus).

Science.gov (United States)

Wheat, Rachel E; Lewis, Stephen B; Wang, Yiwei; Levi, Taal; Wilmers, Christopher C

2017-01-01

Quantifying individual variability in movement behavior is critical to understanding population-level patterns in animals. Here, we explore intraspecific variation in movement strategies of bald eagles ( Haliaeetus leucocephalus ) in the north Pacific, where there is high spatiotemporal resource variability. We tracked 28 bald eagles (five immature, 23 adult) using GPS transmitters between May 2010 and January 2016. We found evidence of four movement strategies among bald eagles in southeastern Alaska and western Canada: breeding individuals that were largely sedentary and remained near nest sites year-round, non-breeding migratory individuals that made regular seasonal travel between northern summer and southern winter ranges, non-breeding localized individuals that displayed fidelity to foraging sites, and non-breeding nomadic individuals with irregular movement. On average, males traveled farther per day than females. Most nomadic individuals were immature, and all residential individuals (i.e. breeders and localized birds) were adults. Alternative movement strategies among north Pacific eagles are likely associated with the age and sex class, as well as breeding status, of an individual. Intraspecific variation in movement strategies within the population results in different space use patterns among contingents, which has important implications for conservation and management.

How hazardous is the Sahara Desert crossing for migratory birds? Indications from satellite tracking of raptors

Science.gov (United States)

Strandberg, Roine; Klaassen, Raymond H. G.; Hake, Mikael; Alerstam, Thomas

2010-01-01

We investigated the risk associated with crossing the Sahara Desert for migrating birds by evaluating more than 90 journeys across this desert by four species of raptors (osprey Pandion haliaetus, honey buzzard Pernis apivorus, marsh harrier Circus aeruginosus and Eurasian hobby Falco subbuteo) recorded by satellite telemetry. Forty per cent of the crossings included events of aberrant behaviours, such as abrupt course changes, slow travel speeds, interruptions, aborted crossings followed by retreats from the desert and failed crossings due to death, indicating difficulties for the migrants. The mortality during the Sahara crossing was 31 per cent per crossing attempt for juveniles (first autumn migration), compared with only 2 per cent for adults (autumn and spring combined). Mortality associated with the Sahara passage made up a substantial fraction (up to about half for juveniles) of the total annual mortality, demonstrating that this passage has a profound influence on survival and fitness of migrants. Aberrant behaviours resulted in late arrival at the breeding grounds and an increased probability of breeding failure (carry-over effects). This study also demonstrates that satellite tracking can be a powerful method to reveal when and where birds are exposed to enhanced risk and mortality during their annual cycles. PMID:19955169

An integrated movement capture and control platform applied towards autonomous movements of surgical robots.

Science.gov (United States)

Daluja, Sachin; Golenberg, Lavie; Cao, Alex; Pandya, Abhilash K; Auner, Gregory W; Klein, Michael D

2009-01-01

Robotic surgery has gradually gained acceptance due to its numerous advantages such as tremor filtration, increased dexterity and motion scaling. There remains, however, a significant scope for improvement, especially in the areas of surgeon-robot interface and autonomous procedures. Previous studies have attempted to identify factors affecting a surgeon's performance in a master-slave robotic system by tracking hand movements. These studies relied on conventional optical or magnetic tracking systems, making their use impracticable in the operating room. This study concentrated on building an intrinsic movement capture platform using microcontroller based hardware wired to a surgical robot. Software was developed to enable tracking and analysis of hand movements while surgical tasks were performed. Movement capture was applied towards automated movements of the robotic instruments. By emulating control signals, recorded surgical movements were replayed by the robot's end-effectors. Though this work uses a surgical robot as the platform, the ideas and concepts put forward are applicable to telerobotic systems in general.

Decision-making by a soaring bird: time, energy and risk considerations at different spatio-temporal scales

Science.gov (United States)

Fluhr, Julie; Horvitz, Nir; Sarrazin, François; Hatzofe, Ohad

2016-01-01

Natural selection theory suggests that mobile animals trade off time, energy and risk costs with food, safety and other pay-offs obtained by movement. We examined how birds make movement decisions by integrating aspects of flight biomechanics, movement ecology and behaviour in a hierarchical framework investigating flight track variation across several spatio-temporal scales. Using extensive global positioning system and accelerometer data from Eurasian griffon vultures (Gyps fulvus) in Israel and France, we examined soaring–gliding decision-making by comparing inbound versus outbound flights (to or from a central roost, respectively), and these (and other) home-range foraging movements (up to 300 km) versus long-range movements (longer than 300 km). We found that long-range movements and inbound flights have similar features compared with their counterparts: individuals reduced journey time by performing more efficient soaring–gliding flight, reduced energy expenditure by flapping less and were more risk-prone by gliding more steeply between thermals. Age, breeding status, wind conditions and flight altitude (but not sex) affected time and energy prioritization during flights. We therefore suggest that individuals facing time, energy and risk trade-offs during movements make similar decisions across a broad range of ecological contexts and spatial scales, presumably owing to similarity in the uncertainty about movement outcomes. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528787

Movement-based Interaction in Camera Spaces

DEFF Research Database (Denmark)

Eriksson, Eva; Riisgaard Hansen, Thomas; Lykke-Olesen, Andreas

2006-01-01

In this paper we present three concepts that address movement-based interaction using camera tracking. Based on our work with several movement-based projects we present four selected applications, and use these applications to leverage our discussion, and to describe our three main concepts space......, relations, and feedback. We see these as central for describing and analysing movement-based systems using camera tracking and we show how these three concepts can be used to analyse other camera tracking applications....

A Palaearctic migratory raptor species tracks shifting prey availability within its wintering range in the Sahel

NARCIS (Netherlands)

Trierweiler, Christiane; Mullie, Wim C.; Drent, Rudi H.; Exo, Klaus-Michael; Komdeur, Jan; Bairlein, Franz; Harouna, Abdoulaye; de Bakker, Marinus; Koks, Ben J.

Mid-winter movements of up to several hundreds of kilometres are typical for many migratory bird species wintering in Africa. Unpredictable temporary food concentrations are thought to result in random movements of such birds, whereas resightings and recoveries of marked birds suggest some degree of

The North Sea Bird Club

International Nuclear Information System (INIS)

Doyle, P.A.T.; Gorman, M.L.; Patterson, I.J.; Howe, S.

1991-01-01

This paper reports that the creation of a club for the purpose of encouraging oil and gas workers to watch birds may not at first seem a viable proposition. To the layperson, birds offshore conjures up an image of hundreds of seagulls following fishing boats, and very little else. Also, the act of birdwatching is not seen as a typical offshore worker's activity. Anyone who has worked on an installation offshore and who has any interest in wildlife will be aware of the occasional presence of land-birds. Two decades ago, prompted by some keen offshore workers, a single oil company set up a monitoring program, which quickly became popular with a number of its employees. Birds seem offshore were recorded on data forms and collected together. At this stage the club was purely another recreation facility; however, when the data were collated it was soon realized that installations offshore were being used as staging posts by birds on migration, and that the information being collected would be of great interest in the study of bird movements. All over Britain, at strategic points on the coastline, there are bird observatories which record the arrival and departure of migrating birds. The presence of several hundred solid structures up and down the North Sea, which are used by birds en route, represents a huge, unique bird observatory, capable of uncovering facts about bird migration which have long eluded land-based scientists. Eleven years ago, the North Sea Bird Club began, composed of eight member companies, a recorder from Aberdeen University and a representative from the Nature Conservancy Council. The club received data from 41 installations, and the recorder collated these on Aberdeen University's computer and produced an annual report of sightings

Unsteady Aerodynamics of Flapping Wing of a Bird

Directory of Open Access Journals (Sweden)

M. Agoes Moelyadi

2013-04-01

Full Text Available The unsteady flow behavior and time-dependent aerodynamic characteristics of the flapping motion of a bird’s wing were investigated using a computational method. During flapping, aerodynamic interactions between bird wing surfaces and surrounding flow may occur, generating local time-dependent flow changes in the flow field and aerodynamic load of birds. To study the effect of flapping speed on unsteady aerodynamic load, two kinds of computational simulations were carried out, namely a quasi-steady and an unsteady simulation. To mimic the movement of the down-stroke and the upstroke of a bird, the flapping path accorded to a sinus function, with the wing attitude changing in dihedral angle and time. The computations of time-dependent viscous flow were based on the solution of the Reynolds Averaged Navier-Stokes equations by applying the k-e turbulence model. In addition, the discretization for the computational domain around the model used multi-block structured grid to provide more accuracy in capturing viscous flow, especially in the vicinity of the wing and body surfaces, to obtain a proper wing-body geometry model. For this research, the seagull bird was chosen, which has high aspect ratio wings with pointed wing-tips and a high camber wing section. The results include mesh movement, velocity contours as well as aerodynamic coefficients of the flapping motion of the bird at various flapping frequencies.

Three-dimensional tracking of small aquatic organisms using fluorescent nanoparticles.

Science.gov (United States)

Ekvall, Mikael T; Bianco, Giuseppe; Linse, Sara; Linke, Heiner; Bäckman, Johan; Hansson, Lars-Anders

2013-01-01

Tracking techniques are vital for the understanding of the biology and ecology of organisms. While such techniques have provided important information on the movement and migration of large animals, such as mammals and birds, scientific advances in understanding the individual behaviour and interactions of small (mm-scale) organisms have been hampered by constraints, such as the sizes of existing tracking devices, in existing tracking methods. By combining biology, chemistry and physics we here present a method that allows three-dimensional (3D) tracking of individual mm-sized aquatic organisms. The method is based on in-vivo labelling of the organisms with fluorescent nanoparticles, so-called quantum dots, and tracking of the organisms in 3D via the quantum-dot fluorescence using a synchronized multiple camera system. It allows for the efficient and simultaneous study of the behaviour of one as well as multiple individuals in large volumes of observation, thus enabling the study of behavioural interactions at the community scale. The method is non-perturbing - we demonstrate that the labelling is not affecting the behavioural response of the organisms - and is applicable over a wide range of taxa, including cladocerans as well as insects, suggesting that our methodological concept opens up for new research fields on individual behaviour of small animals. Hence, this offers opportunities to focus on important biological, ecological and behavioural questions never before possible to address.

Overseas seed dispersal by migratory birds.

Science.gov (United States)

Viana, Duarte S; Gangoso, Laura; Bouten, Willem; Figuerola, Jordi

2016-01-13

Long-distance dispersal (LDD) promotes the colonization of isolated and remote habitats, and thus it has been proposed as a mechanism for explaining the distributions of many species. Birds are key LDD vectors for many sessile organisms such as plants, yet LDD beyond local and regional scales has never been directly observed nor quantified. By sampling birds caught while in migratory flight by GPS-tracked wild falcons, we show that migratory birds transport seeds over hundreds of kilometres and mediate dispersal from mainland to oceanic islands. Up to 1.2% of birds that reached a small island of the Canary Archipelago (Alegranza) during their migration from Europe to Sub-Saharan Africa carried seeds in their guts. The billions of birds making seasonal migrations each year may then transport millions of seeds. None of the plant species transported by the birds occurs in Alegranza and most do not occur on nearby Canary Islands, providing a direct example of the importance of environmental filters in hampering successful colonization by immigrant species. The constant propagule pressure generated by these LDD events might, nevertheless, explain the colonization of some islands. Hence, migratory birds can mediate rapid range expansion or shifts of many plant taxa and determine their distribution. © 2016 The Author(s).

How birds weather the weather: avian migration in the mid-latitudes

NARCIS (Netherlands)

Kemp, M.U.

2012-01-01

The life cycle of many bird species involves the twice-annual movement between a breeding ground and a wintering ground that we refer to as `migration'. To complete these journeys, birds must successfully navigate many obstacles including a dynamic atmosphere. To make optimal use of this

Limitations and mechanisms influencing the migratory performance of soaring birds

Science.gov (United States)

Tricia A. Miller; Brooks Robert P.; Michael J. Lanzone; David Brandes; Jeff Cooper; Junior A. Tremblay; Jay Wilhelm; Adam Duerr; Todd E. Katzner

2016-01-01

Migration is costly in terms of time, energy and safety. Optimal migration theory suggests that individual migratory birds will choose between these three costs depending on their motivation and available resources. To test hypotheses about use of migratory strategies by large soaring birds, we used GPS telemetry to track 18 adult, 13 sub-adult and 15 juvenile Golden...

WT-BIRD. Bird collision monitoring system for multi-megawatt wind turbines

Energy Technology Data Exchange (ETDEWEB)

Wiggelinkhuizen, E.J.; Rademakers, L.W.M.M.; Barhorst, S.A.M. [ECN Wind Energy, Petten (Netherlands); Den Boon, H.J. [E-Connection Project, Bunnik (Netherlands); Dirksen, S. [Bureau Waardenburg, Culemborg (Netherlands)

2007-05-15

A new method for detection and registration of bird collisions has been developed that is suitable for continuous remote operation in both onshore and offshore wind farms. The characteristic sound of a collision is detected by sensors in the blades, which triggers the storage of video registrations and sends an alert message to the operator. A prototype has been tested successfully on a Nordex N80/2.5MW turbine at ECN's Wind turbine Test park Wieringermeer. Compared to other methods employed so far this monitoring system will reduce the uncertainty in the number of birds killed by collisions with wind turbines. Further, the system enables the operator to identify species and to study the collision mechanisms. It has been found that this system can also be used for monitoring of other events in order to save costs for inspection and repair after incidents. For offshore wind farms, the WT-Bird system is currently the only alternative to count the number of bird collisions. Functional tests with tennis balls that were shot against rotating blades showed that the majority of the impacts were detected. The flight track of these dummies and the collision events were clearly visible on the video registrations. During the monitoring period of about one year two bird collisions were detected. The video recordings confirmed that a collision took place and showed that the location of both collisions was near the blade root, which resulted that in both cases the bird was not (immediately) killed. Therefore no corpses could be found beneath the turbine after these events. Also during the rest of the monitoring period no corpses were found beneath the turbine.

Three-dimensional intrafractional movement of prostate measured during real-time tumor-tracking radiotherapy in supine and prone treatment positions

International Nuclear Information System (INIS)

Kitamura, Kei; Shirato, Hiroki; Seppenwoolde, Yvette; Onimaru, Rikiya; Oda, Makoto; Fujita, Katsuhisa; Shimizu, Shinichi; Shinohara, Nobuo; Harabayashi, Toru; Miyasaka, Kazuo

2002-01-01

Purpose: To quantify three-dimensional (3D) movement of the prostate gland with the patient in the supine and prone positions and to analyze the movement frequency for each treatment position. Methods and Materials: The real-time tumor-tracking radiotherapy (RTRT) system was developed to identify the 3D position of a 2-mm gold marker implanted in the prostate 30 times/s using two sets of fluoroscopic images. The linear accelerator was triggered to irradiate the tumor only when the gold marker was located within the region of the planned coordinates relative to the isocenter. Ten patients with prostate cancer treated with RTRT were the subjects of this study. The coordinates of the gold marker were recorded every 0.033 s during RTRT in the supine treatment position for 2 min. The patient was then moved to the prone position, and the marker was tracked for 2 min to acquire data regarding movement in this position. Measurements were taken 5 times for each patient (once a week); a total of 50 sets for the 10 patients was analyzed. The raw data from the RTRT system were filtered to reduce system noise, and the amplitude of movement was then calculated. The discrete Fourier transform of the unfiltered data was performed for the frequency analysis of prostate movement. Results: No apparent difference in movement was found among individuals. The amplitude of 3D movement was 0.1-2.7 mm in the supine and 0.4-24 mm in the prone positions. The amplitude in the supine position was statistically smaller in all directions than that in the prone position (p < 0.0001). The amplitude in the craniocaudal and AP directions was larger than in the left-right direction in the prone position (p < 0.0001). No characteristic movement frequency was detected in the supine position. The respiratory frequency was detected for all patients regarding movement in the craniocaudal and AP directions in the prone position. The results of the frequency analysis suggest that prostate movement is

Tracking Invasive Birds: A Programme for Implementing Dynamic Open Inquiry Learning and Conservation Education

Science.gov (United States)

Zion, Michal; Spektor-Levy, Ornit; Orchan, Yotam; Shwartz, Assaf; Sadeh, Irit; Kark, Salit

2011-01-01

Among potential topics in the new science of biodiversity, understanding the characteristics and impact of invasive birds is an attractive subject to include as part of junior high school biology studies. Birds are aesthetic and raise curiosity. Curiosity about birds, combined with field observations, can stimulate students to ask authentic…

Bird-marking in the Netherlands

NARCIS (Netherlands)

Oort, van E.D.

1911-01-01

Since May of this year the Museum of Natural History at Leyden is carrying into execution the inquiry into migration and other movements of birds in the Netherlands by means of aluminium rings. The results will be published in this periodical and at the same time in Dutch in the periodical of the

Real-time tracking of vertebral body movement with implantable reference microsensors.

Science.gov (United States)

Mularski, Sven; Picht, Thomas; Kuehn, Björn; Kombos, Theodoros; Brock, Mario; Suess, Olaf

2006-05-01

In the spine, navigation techniques serve mainly to control and accurately target insertion of implants. The main source of error is that the spine is not a rigid organ, but rather a chain of semiflexible movement segments. Any intraoperative manipulation of the patient alters the geometry and volumetry as compared to the 3D volume model created from the image data. Thus, the objective of the study was to implement the theoretical principle of microsensor referencing in a model experiment and to clarify which anatomical structures are suitable for intermittent implantation of positional sensors, as illustrated with cervical vertebral bodies. Laboratory tests were conducted using 70 models of human cervical vertebral bodies. The first experiment investigated whether arbitrary movements of vertebral bodies can be tracked with the positional information from the implanted microsensors. The accuracy of this movement monitoring was determined quantitatively on the basis of positional error measurement. In the second experiment, different ventral and dorsal surgical operations were simulated on five models of the cervical spine. Quantifiable measurement values such as the spatial extension of the intervertebral space and the relative positions of the planes of the upper plates were determined. With respect to the differing anatomy of the individual vertebral bodies of the cervical spine, the sensors could be placed securely with a 5x2 mm drill. The registration error (RE) was determined as a root mean square error. The mean value was 0.9425 mm (range: 0.57-1.2 mm; median: 0.9400 mm; SD: 0.1903 mm). The precision of the movement monitoring of the vertebral body was investigated along its three main axes. The error tolerance between post-interventional 3D reconstruction and direct measurement on the model did not exceed 1.3 mm in the distance measurements or 2.5 degrees in the angular measurements. The tomograms on the system monitor could be updated in close to real time

Winter Responses of Forest Birds to Habitat Corridors and Gaps

Directory of Open Access Journals (Sweden)

Colleen Cassady St. Clair

1998-12-01

Full Text Available Forest fragmentation and habitat loss may disrupt the movement or dispersal of forest-dwelling birds. Despite much interest in the severity of these effects and ways of mitigating them, little is known about actual movement patterns in different habitat types. We studied the movement of wintering resident birds, lured by playbacks of mobbing calls, to compare the willingness of forest birds to travel various distances in continuous forest, along narrow corridors (fencerows, and across gaps in forest cover. We also quantified the willingness of Black-capped Chickadees (Poecile atricapillus to cross gaps when alternative forested detour routes were available. All species were less likely to respond to the calls as distance increased to 200 m, although White-breasted Nuthatches (Sitta carolinensis and Hairy Woodpeckers (Picoides villosus were generally less likely to respond than chickadees and Downy Woodpeckers (P. pubescens. Chickadees were as likely to travel in corridors as in continuous forest, but were less likely to cross gaps as the gap distance increased. The other species were less willing to travel in corridors and gaps relative to forest, and the differences among habitats also increased with distance. For chickadees, gap-crossing decisions in the presence of forested detours varied over the range of distances that we tested, and were primarily influenced by detour efficiency (the length of the shortcut relative to the available detour. Over short distances, birds used forested detours, regardless of their efficiency. As absolute distances increased, birds tended to employ larger shortcuts in the open when detour efficiency was low or initial distance in the open was high, but they limited their distance from the nearest forest edge to 25 m. Thus, chickadees were unwilling to cross gaps of > 50 m when they had forested alternatives, yet they sometimes crossed gaps as large as 200 m when no such choice existed. Our results suggest that

Movement initiation in groups of feral horses

NARCIS (Netherlands)

Krueger, Konstanze; Flauger, Birgit; Farmer, Kate; Hemelrijk, Charlotte

Herds of ungulates, flocks of birds, swarms of insects and schools of fish move in coordinated groups. Computer models show that only one or very few animals are needed to initiate and direct movement. To investigate initiation mechanisms further, we studied two ways in which movement can be

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

Science.gov (United States)

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.

Genetic characterization of low-pathogenic avian influenza viruses isolated on the Izumi plain in Japan: possible association of dynamic movements of wild birds with AIV evolution.

Science.gov (United States)

Nakagawa, Hiroko; Okuya, Kosuke; Kawabata, Toshiko; Matsuu, Aya; Takase, Kozo; Kuwahara, Masakazu; Toda, Shigehisa; Ozawa, Makoto

2018-04-01

The Izumi plain in Kagoshima Prefecture, Japan, is an overwintering site of endangered cranes (hooded cranes and white-naped cranes) and of many other migratory birds (including wild ducks) that are considered carriers of avian influenza viruses (AIVs). To assess the risks of a highly pathogenic avian influenza outbreak in the crane populations, we tested various environmental samples for AIVs in this area. In the 2014-2015 winter season, we isolated one AIV of the H6N2 subtype from the cranes' roost water and two AIVs of the H11N9 subtype from a crane fecal sample and a cloacal swab of a dead spot-billed duck. Genetic analysis of these AIV isolates indicated that our H6N2 isolate is genetically close to AIVs isolated from wild birds in Southeast Asian countries, except that the PB1 and NS genes belong to the North American virus lineage. All genes of the two H11N9 isolates are related to AIVs belonging to the Eurasian virus lineage. Notably, in our phylogenetic trees, H11 HA and N9 NA genes showing high sequence similarity to the corresponding genes of isolates from wild birds in South Africa and Spain, respectively, did not cluster in the major groups with recent wild-bird isolates from East Asia. These results suggest that AIVs with viral gene segments derived from various locations and bird species have been brought to the Izumi plain. These findings imply a possible association of dynamic movements of wild birds with AIV evolution.

Detection of patient movement during CBCT examination using video observation compared with an accelerometer-gyroscope tracking system.

Science.gov (United States)

Spin-Neto, Rubens; Matzen, Louise H; Schropp, Lars; Gotfredsen, Erik; Wenzel, Ann

2017-02-01

To compare video observation (VO) with a novel three-dimensional registration method, based on an accelerometer-gyroscope (AG) system, to detect patient movement during CBCT examination. The movements were further analyzed according to complexity and patient age. In 181 patients (118 females/63 males; age average 30 years, range: 9-84 years), 206 CBCT examinations were performed, which were video-recorded during examination. An AG was, at the same time, attached to the patient head to track head position in three dimensions. Three observers scored patient movement (yes/no) by VO. AG provided movement data on the x-, y- and z-axes. Thresholds for AG-based registration were defined at 0.5, 1, 2, 3 and 4 mm (movement distance). Movement detected by VO was compared with that registered by AG, according to movement complexity (uniplanar vs multiplanar, as defined by AG) and patient age (≤15, 16-30 and ≥31 years). According to AG, movement ≥0.5 mm was present in 160 (77.7%) examinations. According to VO, movement was present in 46 (22.3%) examinations. One VO-detected movement was not registered by AG. Overall, VO did not detect 71.9% of the movements registered by AG at the 0.5-mm threshold. At a movement distance ≥4 mm, 20% of the AG-registered movements were not detected by VO. Multiplanar movements such as lateral head rotation (72.1%) and nodding/swallowing (52.6%) were more often detected by VO in comparison with uniplanar movements, such as head lifting (33.6%) and anteroposterior translation (35.6%), at the 0.5-mm threshold. The prevalence of patients who move was highest in patients younger than 16 years (64.3% for VO and 92.3% for AG-based registration at the 0.5-mm threshold). AG-based movement registration resulted in a higher prevalence of patient movement during CBCT examination than VO-based registration. Also, AG-registered multiplanar movements were more frequently detected by VO than uniplanar movements. The prevalence of patients who move

Three-dimensional tracking of small aquatic organisms using fluorescent nanoparticles.

Directory of Open Access Journals (Sweden)

Mikael T Ekvall

Full Text Available Tracking techniques are vital for the understanding of the biology and ecology of organisms. While such techniques have provided important information on the movement and migration of large animals, such as mammals and birds, scientific advances in understanding the individual behaviour and interactions of small (mm-scale organisms have been hampered by constraints, such as the sizes of existing tracking devices, in existing tracking methods. By combining biology, chemistry and physics we here present a method that allows three-dimensional (3D tracking of individual mm-sized aquatic organisms. The method is based on in-vivo labelling of the organisms with fluorescent nanoparticles, so-called quantum dots, and tracking of the organisms in 3D via the quantum-dot fluorescence using a synchronized multiple camera system. It allows for the efficient and simultaneous study of the behaviour of one as well as multiple individuals in large volumes of observation, thus enabling the study of behavioural interactions at the community scale. The method is non-perturbing - we demonstrate that the labelling is not affecting the behavioural response of the organisms - and is applicable over a wide range of taxa, including cladocerans as well as insects, suggesting that our methodological concept opens up for new research fields on individual behaviour of small animals. Hence, this offers opportunities to focus on important biological, ecological and behavioural questions never before possible to address.

Movement ecology of migration in turkey vultures.

Science.gov (United States)

Mandel, J T; Bildstein, K L; Bohrer, G; Winkler, D W

2008-12-09

We develop individual-based movement ecology models (MEM) to explore turkey vulture (Cathartes aura) migration decisions at both hourly and daily scales. Vulture movements in 10 migration events were recorded with satellite-reporting GPS sensors, and flight behavior was observed visually, aided by on-the-ground VHF radio-tracking. We used the North American Regional Reanalysis dataset to obtain values for wind speed, turbulent kinetic energy (TKE), and cloud height and used a digital elevation model for a measure of terrain ruggedness. A turkey vulture fitted with a heart-rate logger during 124 h of flight during 38 contiguous days showed only a small increase in mean heart rate as distance traveled per day increased, which suggests that, unlike flapping, soaring flight does not lead to greatly increased metabolic costs. Data from 10 migrations for 724 hourly segments and 152 daily segments showed that vultures depended heavily upon high levels of TKE in the atmospheric boundary layer to increase flight distances and maintain preferred bearings at both hourly and daily scales. We suggest how the MEM can be extended to other spatial and temporal scales of avian migration. Our success in relating model-derived atmospheric variables to migration indicates the potential of using regional reanalysis data, as here, and potentially other regional, higher-resolution, atmospheric models in predicting changing movement patterns of soaring birds under various scenarios of climate and land use change.

Using radar to advance migratory bird management: An interagency collaboration

Science.gov (United States)

Sojda, R.; Ruth, J.M.; Barrow, W.C.; Dawson, D.K.; Diehl, R.H.; Manville, A.; Green, M.T.; Krueper, D.J.; Johnston, S.

2005-01-01

Migratory birds face many changes to the landscapes they traverse and the habitats they use. Wind turbines and communications towers, which pose hazards to birds and bats in flight, are being erected across the United States and offshore. Human activities can also destroy or threaten habitats critical to birds during migratory passage, and climate change appears to be altering migratory patterns. The U.S. Fish and Wildlife Service (USFWS) and other agencies are under increasing pressure to identify and evaluate movement patterns and habitats used during migration and other times.

Phenological shifts conserve thermal niches in North American birds and reshape expectations for climate-driven range shifts.

Science.gov (United States)

Socolar, Jacob B; Epanchin, Peter N; Beissinger, Steven R; Tingley, Morgan W

2017-12-05

Species respond to climate change in two dominant ways: range shifts in latitude or elevation and phenological shifts of life-history events. Range shifts are widely viewed as the principal mechanism for thermal niche tracking, and phenological shifts in birds and other consumers are widely understood as the principal mechanism for tracking temporal peaks in biotic resources. However, phenological and range shifts each present simultaneous opportunities for temperature and resource tracking, although the possible role for phenological shifts in thermal niche tracking has been widely overlooked. Using a canonical dataset of Californian bird surveys and a detectability-based approach for quantifying phenological signal, we show that Californian bird communities advanced their breeding phenology by 5-12 d over the last century. This phenological shift might track shifting resource peaks, but it also reduces average temperatures during nesting by over 1 °C, approximately the same magnitude that average temperatures have warmed over the same period. We further show that early-summer temperature anomalies are correlated with nest success in a continental-scale database of bird nests, suggesting avian thermal niches might be broadly limited by temperatures during nesting. These findings outline an adaptation surface where geographic range and breeding phenology respond jointly to constraints imposed by temperature and resource phenology. By stabilizing temperatures during nesting, phenological shifts might mitigate the need for range shifts. Global change ecology will benefit from further exploring phenological adjustment as a potential mechanism for thermal niche tracking and vice versa.

Self-adaptive robot training of stroke survivors for continuous tracking movements

Directory of Open Access Journals (Sweden)

Morasso Pietro

2010-03-01

Full Text Available Abstract Background Although robot therapy is progressively becoming an accepted method of treatment for stroke survivors, few studies have investigated how to adapt the robot/subject interaction forces in an automatic way. The paper is a feasibility study of a novel self-adaptive robot controller to be applied with continuous tracking movements. Methods The haptic robot Braccio di Ferro is used, in relation with a tracking task. The proposed control architecture is based on three main modules: 1 a force field generator that combines a non linear attractive field and a viscous field; 2 a performance evaluation module; 3 an adaptive controller. The first module operates in a continuous time fashion; the other two modules operate in an intermittent way and are triggered at the end of the current block of trials. The controller progressively decreases the gain of the force field, within a session, but operates in a non monotonic way between sessions: it remembers the minimum gain achieved in a session and propagates it to the next one, which starts with a block whose gain is greater than the previous one. The initial assistance gains are chosen according to a minimal assistance strategy. The scheme can also be applied with closed eyes in order to enhance the role of proprioception in learning and control. Results The preliminary results with a small group of patients (10 chronic hemiplegic subjects show that the scheme is robust and promotes a statistically significant improvement in performance indicators as well as a recalibration of the visual and proprioceptive channels. The results confirm that the minimally assistive, self-adaptive strategy is well tolerated by severely impaired subjects and is beneficial also for less severe patients. Conclusions The experiments provide detailed information about the stability and robustness of the adaptive controller of robot assistance that could be quite relevant for the design of future large scale

Key Questions in Marine Megafauna Movement Ecology

KAUST Repository

Hays, Graeme C.; Ferreira, Luciana C.; Sequeira, Ana M.M.; Meekan, Mark G.; Duarte, Carlos M.; Bailey, Helen; Bailleul, Fred; Bowen, W. Don; Caley, M. Julian; Costa, Daniel P.; Eguí luz, Victor M.; Fossette, Sabrina; Friedlaender, Ari S.; Gales, Nick; Gleiss, Adrian C.; Gunn, John; Harcourt, Rob; Hazen, Elliott L.; Heithaus, Michael R.; Heupel, Michelle; Holland, Kim; Horning, Markus; Jonsen, Ian; Kooyman, Gerald L.; Lowe, Christopher G.; Madsen, Peter T.; Marsh, Helene; Phillips, Richard A.; Righton, David; Ropert-Coudert, Yan; Sato, Katsufumi; Shaffer, Scott A.; Simpfendorfer, Colin A.; Sims, David W.; Skomal, Gregory; Takahashi, Akinori; Trathan, Philip N.; Wikelski, Martin; Womble, Jamie N.; Thums, Michele

2016-01-01

It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology. Technical advances make this an exciting time for animal movement studies, with a range of small, reliable data-loggers and transmitters that can record horizontal and vertical movements as well as aspects of physiology and reproductive biology.Forty experts identified key questions in the field of movement ecology.Questions have broad applicability across species, habitats, and spatial scales, and apply to animals in both marine and terrestrial habitats as well as both vertebrates and invertebrates, including birds, mammals, reptiles, fish, insects, and plankton. © 2016 Elsevier Ltd.

Key Questions in Marine Megafauna Movement Ecology

KAUST Repository

Hays, Graeme C.

2016-03-12

It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology. Technical advances make this an exciting time for animal movement studies, with a range of small, reliable data-loggers and transmitters that can record horizontal and vertical movements as well as aspects of physiology and reproductive biology.Forty experts identified key questions in the field of movement ecology.Questions have broad applicability across species, habitats, and spatial scales, and apply to animals in both marine and terrestrial habitats as well as both vertebrates and invertebrates, including birds, mammals, reptiles, fish, insects, and plankton. © 2016 Elsevier Ltd.

The reliability and validity of subjective notational analysis in comparison to global positioning system tracking to assess athlete movement patterns.

Science.gov (United States)

Doğramac, Sera N; Watsford, Mark L; Murphy, Aron J

2011-03-01

Subjective notational analysis can be used to track players and analyse movement patterns during match-play of team sports such as futsal. The purpose of this study was to establish the validity and reliability of the Event Recorder for subjective notational analysis. A course was designed, replicating ten minutes of futsal match-play movement patterns, where ten participants undertook the course. The course allowed a comparison of data derived from subjective notational analysis, to the known distances of the course, and to GPS data. The study analysed six locomotor activity categories, focusing on total distance covered, total duration of activities and total frequency of activities. The values between the known measurements and the Event Recorder were similar, whereas the majority of significant differences were found between the Event Recorder and GPS values. The reliability of subjective notational analysis was established with all ten participants being analysed on two occasions, as well as analysing five random futsal players twice during match-play. Subjective notational analysis is a valid and reliable method of tracking player movements, and may be a preferred and more effective method than GPS, particularly for indoor sports such as futsal, and field sports where short distances and changes in direction are observed.

Why birds with deferred sexual maturity are sedentary on islands: a systematic review.

Directory of Open Access Journals (Sweden)

Miguel Ferrer

Full Text Available BACKGROUND: Island faunas have played central roles in the development of evolutionary biology and ecology. Birds are among the most studied organisms on islands, in part because of their dispersal powers linked to migration. Even so, we lack of information about differences in the movement ecology of island versus mainland populations of birds. METHODOLOGY/PRINCIPAL FINDINGS: Here we present a new general pattern indicating that large birds with deferred sexual maturity are sedentary on islands, and that they become so even when they are migratory on the mainland. Density-dependent variation in the age at first breeding affects the survivorship of insular populations and this, in turn, affects the movement ecology of large birds. Because density-dependent variation in the age of first breeding is critical to the long-term survival of small isolated populations of long-lived species, migratory forms can successfully colonize islands only if they become sedentary once there. Analyses of the movement ecology of continental and insular populations of 314 species of raptors, 113 species of Ciconiiformes and 136 species of passerines, along with individual-based population simulations confirm this prediction. CONCLUSIONS: This finding has several consequences for speciation, colonization and survival of small isolated population of species with deferred sexual maturity.

Material Tracking Using LANMAS

International Nuclear Information System (INIS)

Armstrong, F.

2010-01-01

LANMAS is a transaction-based nuclear material accountability software product developed to replace outdated and legacy accountability systems throughout the DOE. The core underlying purpose of LANMAS is to track nuclear materials inventory and report transactions (movement, mixing, splitting, decay, etc.) to the Nuclear Materials Management and Safeguards System (NMMSS). While LANMAS performs those functions well, there are many additional functions provided by the software product. As a material is received onto a site or created at a site, its entire lifecycle can be tracked in LANMAS complete to its termination of safeguards. There are separate functions to track material movements between and within material balance areas (MBAs). The level of detail for movements within a MBA is configurable by each site and can be as high as a site designation or as detailed as building/room/rack/row/position. Functionality exists to track the processing of materials, either as individual items or by modeling a bulk process as an individual item to track inputs and outputs from the process. In cases where sites have specialized needs, the system is designed to be flexible so that site specific functionality can be integrated into the product. This paper will demonstrate how the software can be used to input material into an account and track it to its termination of safeguards.

Rates of movement of threatened bird species between IUCN red list categories and toward extinction.

Science.gov (United States)

Brooke, M de L; Butchart, S H M; Garnett, S T; Crowley, G M; Mantilla-Beniers, N B; Stattersfield, A J

2008-04-01

In recent centuries bird species have been deteriorating in status and becoming extinct at a rate that may be 2-3 orders of magnitude higher than in prehuman times. We examined extinction rates of bird species designated critically endangered in 1994 and the rate at which species have moved through the IUCN (World Conservation Union) Red List categories of extinction risk globally for the period 1988-2004 and regionally in Australia from 1750 to 2000. For Australia we drew on historical accounts of the extent and condition of species habitats, spread of invasive species, and changes in sighting frequencies. These data sets permitted comparison of observed rates of movement through the IUCN Red List categories with novel predictions based on the IUCN Red List criterion E, which relates to explicit extinction probabilities determined, for example, by population viability analysis. The comparison also tested whether species listed on the basis of other criteria face a similar probability of moving to a higher threat category as those listed under criterion E. For the rate at which species moved from vulnerable to endangered, there was a good match between observations and predictions, both worldwide and in Australia. Nevertheless, species have become extinct at a rate that, although historically high, is 2 (Australia) to 10 (globally) times lower than predicted. Although the extinction probability associated with the critically endangered category may be too high, the shortfall in realized extinctions can also be attributed to the beneficial impact of conservation intervention. These efforts may have reduced the number of global extinctions from 19 to 3 and substantially slowed the extinction trajectory of 33 additional critically endangered species. Our results suggest that current conservation action benefits species on the brink of extinction, but is less targeted at or has less effect on moderately threatened species.

Combining radar systems to get a 3D - picture of the bird migration

NARCIS (Netherlands)

Liechti, F.; Dokter, A.; Shamoun, J.; van Gasteren, H.; Holleman, I.

2008-01-01

For military training flights bird strikes en route are still a severe problem. To reduce collisions an international project has been launched by the European Space agency (ESA), aiming 1) for a compilation of information on current bird movements by various sensors, 2) to combine them in a single

Assessing the utility of photoswitchable fluorescent proteins for tracking intercellular protein movement in the Arabidopsis root.

Directory of Open Access Journals (Sweden)

Shuang Wu

Full Text Available One way in which cells communicate is through the direct transfer of proteins. In plants, many of these proteins are transcription factors, which are made by one cell type and traffic into another. In order to understand how this movement occurs and its role in development, we would like to track this movement in live, intact plants in real-time. Here we examine the utility of the photoconvertible proteins, Dendra2 and (to a lesser extent EosFP as tags for studying intracellular and intercellular protein movement in the Arabidopsis root. To this end, we made fusions between Dendra2 and six mobile transcription factors. Our results show that Dendra2 is an effective tool for studying protein movement between plant cells. Interestingly, we found that Dendra2 could not simply be swapped into existing constructs that had originally contained GFP. Most of the fusions made in this way failed to produce a fluorescent fusion. In addition we found that the optimal settings for photoconversion of Dendra2 in stably transformed roots were different from what has been published for photoconversion in transient assays in plants or in animal cells. By modifying the confocal setting, we were able to photoconvert Dendra2 in all cell layers in the root. However the efficiency of photoconversion was affected by the position of the cell layer within the root, with more internal tissues requiring more energy. By examining the Dendra2 fusions, we confirmed the mobility of the SHORT-ROOT (SHR and CAPRICE (CPC transcription factors between cells and we further discovered that SHR movement in stele and CPC movement in the epidermis are non-directional.

Hawk eyes II: diurnal raptors differ in head movement strategies when scanning from perches.

Science.gov (United States)

O'Rourke, Colleen T; Pitlik, Todd; Hoover, Melissa; Fernández-Juricic, Esteban

2010-09-22

Relatively little is known about the degree of inter-specific variability in visual scanning strategies in species with laterally placed eyes (e.g., birds). This is relevant because many species detect prey while perching; therefore, head movement behavior may be an indicator of prey detection rate, a central parameter in foraging models. We studied head movement strategies in three diurnal raptors belonging to the Accipitridae and Falconidae families. We used behavioral recording of individuals under field and captive conditions to calculate the rate of two types of head movements and the interval between consecutive head movements. Cooper's Hawks had the highest rate of regular head movements, which can facilitate tracking prey items in the visually cluttered environment they inhabit (e.g., forested habitats). On the other hand, Red-tailed Hawks showed long intervals between consecutive head movements, which is consistent with prey searching in less visually obstructed environments (e.g., open habitats) and with detecting prey movement from a distance with their central foveae. Finally, American Kestrels have the highest rates of translational head movements (vertical or frontal displacements of the head keeping the bill in the same direction), which have been associated with depth perception through motion parallax. Higher translational head movement rates may be a strategy to compensate for the reduced degree of eye movement of this species. Cooper's Hawks, Red-tailed Hawks, and American Kestrels use both regular and translational head movements, but to different extents. We conclude that these diurnal raptors have species-specific strategies to gather visual information while perching. These strategies may optimize prey search and detection with different visual systems in habitat types with different degrees of visual obstruction.

A novel tracking tool for the analysis of plant-root tip movements

International Nuclear Information System (INIS)

Russino, A; Ascrizzi, A; Popova, L; Tonazzini, A; Mancuso, S; Mazzolai, B

2013-01-01

The growth process of roots consists of many activities, such as exploring the soil volume, mining minerals, avoiding obstacles and taking up water to fulfil the plant's primary functions, that are performed differently, depending on environmental conditions. Root movements are strictly related to a root decision strategy, which helps plants to survive under stressful conditions by optimizing energy consumption. In this work, we present a novel image-analysis tool to study the kinematics of the root tip (apex), named analyser for root tip tracks (ARTT). The software implementation combines a segmentation algorithm with additional software imaging filters in order to realize a 2D tip detection. The resulting paths, or tracks, arise from the sampled tip positions through the acquired images during the growth. ARTT allows work with no markers and deals autonomously with new emerging root tips, as well as handling a massive number of data relying on minimum user interaction. Consequently, ARTT can be used for a wide range of applications and for the study of kinematics in different plant species. In particular, the study of the root growth and behaviour could lead to the definition of novel principles for the penetration and/or control paradigms for soil exploration and monitoring tasks. The software capabilities were demonstrated by experimental trials performed with Zea mays and Oryza sativa. (paper)

An overview of migratory birds in Brazil

Directory of Open Access Journals (Sweden)

Marina Somenzari

2018-03-01

Full Text Available Abstract We reviewed the occurrences and distributional patterns of migratory species of birds in Brazil. A species was classified as migratory when at least part of its population performs cyclical, seasonal movements with high fidelity to its breeding grounds. Of the 1,919 species of birds recorded in Brazil, 198 (10.3% are migratory. Of these, 127 (64% were classified as Migratory and 71 (36% as Partially Migratory. A few species (83; 4.3% were classified as Vagrant and eight (0,4% species could not be defined due to limited information available, or due to conflicting data.

Tracking movement and temperature selection of larvae of two forensically important blow fly species within a "maggot mass".

Science.gov (United States)

Johnson, Aidan P; Wighton, Samuel J; Wallman, James F

2014-11-01

The current study responds to the lack of understanding about the temperatures experienced by individual blow fly larvae within "maggot masses." The temperature selection of both aggregating (in a mass) and nonaggregating larvae was compared and their pattern of movement assessed. Infrared imaging determined the temperatures within a mass and in the vicinity of the constituent individual larvae, whose movements were tracked by dyeing their tissues red. Individual Chrysomya rufifacies larvae selected temperatures above 27°C, significantly higher than the temperature selected by Calliphora vicina larvae (24.5°C). However, this same difference was not seen within a mass, with both species selecting temperatures around 28°C. Larval movement in a mass was nonrandom, indicating that larvae actively select their position in a mass. Furthermore, larvae have a strong tendency to select the hottest part of a mass; therefore, maximum mass temperatures might provide a reliable proxy for the actual temperatures experienced by larvae. © 2014 American Academy of Forensic Sciences.

Optimal transcostal high-intensity focused ultrasound with combined real-time 3D movement tracking and correction

International Nuclear Information System (INIS)

Marquet, F; Aubry, J F; Pernot, M; Fink, M; Tanter, M

2011-01-01

Recent studies have demonstrated the feasibility of transcostal high intensity focused ultrasound (HIFU) treatment in liver. However, two factors limit thermal necrosis of the liver through the ribs: the energy deposition at focus is decreased by the respiratory movement of the liver and the energy deposition on the skin is increased by the presence of highly absorbing bone structures. Ex vivo ablations were conducted to validate the feasibility of a transcostal real-time 3D movement tracking and correction mode. Experiments were conducted through a chest phantom made of three human ribs immersed in water and were placed in front of a 300 element array working at 1 MHz. A binarized apodization law introduced recently in order to spare the rib cage during treatment has been extended here with real-time electronic steering of the beam. Thermal simulations have been conducted to determine the steering limits. In vivo 3D-movement detection was performed on pigs using an ultrasonic sequence. The maximum error on the transcostal motion detection was measured to be 0.09 ± 0.097 mm on the anterior–posterior axis. Finally, a complete sequence was developed combining real-time 3D transcostal movement correction and spiral trajectory of the HIFU beam, allowing the system to treat larger areas with optimized efficiency. Lesions as large as 1 cm in diameter have been produced at focus in excised liver, whereas no necroses could be obtained with the same emitted power without correcting the movement of the tissue sample.

Bird specimens track 135 years of atmospheric black carbon and environmental policy

Science.gov (United States)

DuBay, Shane G.; Fuldner, Carl C.

2017-10-01

Atmospheric black carbon has long been recognized as a public health and environmental concern. More recently, black carbon has been identified as a major, ongoing contributor to anthropogenic climate change, thus making historical emission inventories of black carbon an essential tool for assessing past climate sensitivity and modeling future climate scenarios. Current estimates of black carbon emissions for the early industrial era have high uncertainty, however, because direct environmental sampling is sparse before the mid-1950s. Using photometric reflectance data of >1,300 bird specimens drawn from natural history collections, we track relative ambient concentrations of atmospheric black carbon between 1880 and 2015 within the US Manufacturing Belt, a region historically reliant on coal and dense with industry. Our data show that black carbon levels within the region peaked during the first decade of the 20th century. Following this peak, black carbon levels were positively correlated with coal consumption through midcentury, after which they decoupled, with black carbon concentrations declining as consumption continued to rise. The precipitous drop in atmospheric black carbon at midcentury reflects policies promoting burning efficiency and fuel transitions rather than regulating emissions alone. Our findings suggest that current emission inventories based on predictive modeling underestimate levels of atmospheric black carbon for the early industrial era, suggesting that the contribution of black carbon to past climate forcing may also be underestimated. These findings build toward a spatially dynamic emission inventory of black carbon based on direct environmental sampling.

Body-Part Tracking of Infants

DEFF Research Database (Denmark)

Olsen, Mikkel Damgaard; Herskind, Anna; Nielsen, Jens Bo

2014-01-01

Motion tracking is a widely used technique to analyze and measure adult human movement. However, these methods cannot be transferred directly to motion tracking of infants due to the big differences in the underlying human model. However, motion tracking of infants can be used for automatic...

Bird Movements and Behaviors in the Gulf Coast Region: Relation to Potential Wind-Energy Developments

Energy Technology Data Exchange (ETDEWEB)

Morrison, M. L.

2006-06-01

The purpose of this paper is to discuss the possible impacts of wind development to birds along the lower Gulf Coast, including both proposed near-shore and offshore developments. The report summarizes wind resources in Texas, discusses timing and magnitude of bird migration as it relates to wind development, reviews research that has been conducted throughout the world on near- and offshore developments, and provides recommendations for research that will help guide wind development that minimizes negative impacts to birds and other wildlife resources.

Hypersonic sliding target tracking in near space

Directory of Open Access Journals (Sweden)

Xiang-yu Zhang

2015-12-01

Full Text Available To improve the tracking accuracy of hypersonic sliding target in near space, the influence of target hypersonic movement on radar detection and tracking is analyzed, and an IMM tracking algorithm is proposed based on radial velocity compensating and cancellation processing of high dynamic biases under the earth centered earth fixed (ECEF coordinate. Based on the analysis of effect of target hypersonic movement, a measurement model is constructed to reduce the filter divergence which is caused by the model mismatch. The high dynamic biases due to the target hypersonic movement are approximately compensated through radial velocity estimation to achieve the hypersonic target tracking at low systematic biases in near space. The high dynamic biases are further eliminated by the cancellation processing of different radars, in which the track association problem can be solved when the dynamic biases are low. An IMM algorithm based on constant acceleration (CA, constant turning (CT and Singer models is used to achieve the hypersonic sliding target tracking in near space. Simulation results show that the target tracking in near space can be achieved more effectively by using the proposed algorithm.

A survey of head movement during clinical brain SPECT using an optical tracking system

International Nuclear Information System (INIS)

Pandos, G.; Barnden, L.; Lineage, H.; Smith, T.; Unger, S.

2002-01-01

Full text: The aim of this study was to survey patient motion during clinical brain SPECT using a commercial motion detection system called Polaris. Polaris is an optical tracker that remotely tracks head position and orientation via a small target attached to the patient. Its accuracy for position measurement is 1mm or 1 degree (deg), 33% moved > 2mm or 2deg and 10% moved > 4mm or 4deg. 65% of subjects moved 3 or more times. Motion in the D and P groups was equally likely to be small (<3mm or <3deg) or large and equally likely to occur early or late during acquisition. Motion in the N, F and C groups was less likely to be large and for N and F more likely to occur late in the acquisition suggesting fatigue was the main cause. The most common large movements were anterior-posterior translations and axial (Z) rotations. Significant head movement is common in brain SPECT, particularly in dementia and psychiatric subjects, and accurate motion correction is desirable to maintain image quality. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

Advancing migratory bird conservation and management by using radar: An interagency collaboration

Science.gov (United States)

Ruth, Janet M.; Barrow, Wylie C.; Sojda, Richard S.; Dawson, Deanna K.; Diehl, Robert H.; Manville, Albert; Green, Michael T.; Krueper, David J.; Johnston, Scott

2005-01-01

Migratory birds face many changes to the landscapes they traverse and the habitats they use. Wind turbines and communications towers, which pose hazards to birds and bats in flight, are being erected or proposed across the United States and offshore. Human activities can also destroy or threaten habitats critical to birds during migratory passage, and climate change appears to be altering migratory patterns. The U.S. Fish and Wildlife Service (USFWS) and other agencies are under increasing pressure to identify and evaluate movement patterns and habitats used during migration and other times.

Avian Influenza in Migratory Birds : Regional Surveillance and ...

International Development Research Centre (IDRC) Digital Library (Canada)

Outbreaks may only occur after transmission from migratory species to domestic flocks through local amplification and secondary spread through the movement of poultry or people, as well as equipment or vehicles contaminated by sick birds. The Asia Partnership for Avian Influenza Research (APAIR) brings together ...

9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Certificate for pet birds, commercial birds, zoological birds, and research birds. 93.104 Section 93.104 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN...

Virginia ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, passerine birds, and gulls...

Utilization of optical tracking to validate a software-driven isocentric approach to robotic couch movements for proton radiotherapy

International Nuclear Information System (INIS)

Hsi, Wen C.; Zeidan, Omar A.; Law, Aaron; Schreuder, Andreas N.

2014-01-01

Purpose: An optical tracking and positioning system (OTPS) was developed to validate the software-driven isocentric (SDI) approach to control the six-degrees-of-freedom movement of a robotic couch. Methods: The SDI approach to movements rotating around a predefined isocenter, referred to as a GeoIso, instead of a mechanical pivot point was developed by the robot automation industry. With robotic couch-sag corrections for weight load in a traditional SDI approach, movements could be accurately executed for a GeoIso located within a 500 mm cubic volume on the couch for treatments. The accuracy of SDI movement was investigated using the OTPS. The GeoIso was assumed to align with the proton beam isocenter (RadIso) for gantry at the reference angle. However, the misalignment between GeoIso and RadIso was quantitatively investigated by measuring the displacements at various couch angles for a target placed at the RadIso at an initial couch angle. When circular target displacements occur on a plane, a relative isocenter shift (RIS) correction could be applied in the SDI movement to minimize target displacements. Target displacements at a fixed gantry angle without and with RIS correction were measured for 12 robotic couches. Target displacements for various gantry angles were performed on three couches in gantry rooms to study the gantry-induced RadIso shift. The RIS correction can also be applied for the RadIso shift. A new SDI approach incorporating the RIS correction with the couch sag is described in this study. In parallel, the accuracy of SDI translation movements for various weight loads of patients on the couch was investigated during positioning of patients for proton prostate treatments. Results: For a fixed gantry angle, measured target displacements without RIS correction for couch rotations in the horizontal plane varied from 4 to 20 mm. However, measured displacements perpendicular to couch rotation plane were about 2 mm for all couches. Extracted

Utilization of optical tracking to validate a software-driven isocentric approach to robotic couch movements for proton radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Hsi, Wen C., E-mail: Wen.Hsi@Mclaren.org, E-mail: Wenchien.hsi@sphic.org.cn; Zeidan, Omar A., E-mail: omar.zeidan@orlandohealth.com [ProCure Proton Therapy Center, Oklahoma City, Oklahoma 73142 (United States); Law, Aaron; Schreuder, Andreas N., E-mail: niek.schreuder@provisionhp.com [ProCure Training and Development Center, Bloomington, Indiana 47404 (United States)

2014-08-15

Purpose: An optical tracking and positioning system (OTPS) was developed to validate the software-driven isocentric (SDI) approach to control the six-degrees-of-freedom movement of a robotic couch. Methods: The SDI approach to movements rotating around a predefined isocenter, referred to as a GeoIso, instead of a mechanical pivot point was developed by the robot automation industry. With robotic couch-sag corrections for weight load in a traditional SDI approach, movements could be accurately executed for a GeoIso located within a 500 mm cubic volume on the couch for treatments. The accuracy of SDI movement was investigated using the OTPS. The GeoIso was assumed to align with the proton beam isocenter (RadIso) for gantry at the reference angle. However, the misalignment between GeoIso and RadIso was quantitatively investigated by measuring the displacements at various couch angles for a target placed at the RadIso at an initial couch angle. When circular target displacements occur on a plane, a relative isocenter shift (RIS) correction could be applied in the SDI movement to minimize target displacements. Target displacements at a fixed gantry angle without and with RIS correction were measured for 12 robotic couches. Target displacements for various gantry angles were performed on three couches in gantry rooms to study the gantry-induced RadIso shift. The RIS correction can also be applied for the RadIso shift. A new SDI approach incorporating the RIS correction with the couch sag is described in this study. In parallel, the accuracy of SDI translation movements for various weight loads of patients on the couch was investigated during positioning of patients for proton prostate treatments. Results: For a fixed gantry angle, measured target displacements without RIS correction for couch rotations in the horizontal plane varied from 4 to 20 mm. However, measured displacements perpendicular to couch rotation plane were about 2 mm for all couches. Extracted

Utilization of optical tracking to validate a software-driven isocentric approach to robotic couch movements for proton radiotherapy.

Science.gov (United States)

Hsi, Wen C; Law, Aaron; Schreuder, Andreas N; Zeidan, Omar A

2014-08-01

An optical tracking and positioning system (OTPS) was developed to validate the software-driven isocentric (SDI) approach to control the six-degrees-of-freedom movement of a robotic couch. The SDI approach to movements rotating around a predefined isocenter, referred to as a GeoIso, instead of a mechanical pivot point was developed by the robot automation industry. With robotic couch-sag corrections for weight load in a traditional SDI approach, movements could be accurately executed for a GeoIso located within a 500 mm cubic volume on the couch for treatments. The accuracy of SDI movement was investigated using the OTPS. The GeoIso was assumed to align with the proton beam isocenter (RadIso) for gantry at the reference angle. However, the misalignment between GeoIso and RadIso was quantitatively investigated by measuring the displacements at various couch angles for a target placed at the RadIso at an initial couch angle. When circular target displacements occur on a plane, a relative isocenter shift (RIS) correction could be applied in the SDI movement to minimize target displacements. Target displacements at a fixed gantry angle without and with RIS correction were measured for 12 robotic couches. Target displacements for various gantry angles were performed on three couches in gantry rooms to study the gantry-induced RadIso shift. The RIS correction can also be applied for the RadIso shift. A new SDI approach incorporating the RIS correction with the couch sag is described in this study. In parallel, the accuracy of SDI translation movements for various weight loads of patients on the couch was investigated during positioning of patients for proton prostate treatments. For a fixed gantry angle, measured target displacements without RIS correction for couch rotations in the horizontal plane varied from 4 to 20 mm. However, measured displacements perpendicular to couch rotation plane were about 2 mm for all couches. Extracted misalignments of GeoIso and RadIso in

Rice production systems and avian influenza: Interactions between mixed-farming systems, poultry and wild birds

Science.gov (United States)

Muzaffar, S.B.; Takekawa, John Y.; Prosser, D.J.; Newman, S.H.; Xiao, X.

2010-01-01

Wild waterfowl are the reservoir for avian influenza viruses (AIVs), a family of RNA viruses that may cause mild sickness in waterbirds. Emergence of H5N1, a highly pathogenic avian influenza (HPAI) strain, causing severe disease and mortality in wild birds, poultry and humans, had raised concerns about the role of wild birds in possible transmission of the disease. In this review, the link between rice production systems, poultry production systems, and wild bird ecology is examined to assess the extent to which these interactions could contribute towards the persistence and evolution of HPAI H5N1. The rice (Oryza sativa) and poultry production systems in Asia described, and then migration and movements of wild birds discussed. Mixed farming systems in Asia and wild bird movement and migration patterns create opportunities for the persistence of low pathogenic AIVs in these systems. Nonetheless, there is no evidence of long-term persistence of HPAI viruses (including the H5N1 subtype) in the wild. There are still significant gaps in the understanding of how AIVs circulate in rice systems. A better understanding of persistence of AIVs in rice farms, particularly of poultry origins, is essential in limiting exchange of AIVs between mixed-farming systems, poultry and wild birds.

Eye tracking social preferences

NARCIS (Netherlands)

Jiang, Ting; Potters, Jan; Funaki, Yukihiko

We hypothesize that if people are motivated by a particular social preference, then choosing in accordance with this preference will lead to an identifiable pattern of eye movements. We track eye movements while subjects make choices in simple three-person distribution experiments. We characterize

Do birds select habitat or food resources? Nearctic-neotropic migrants in northeastern Costa Rica

Science.gov (United States)

Jared D. Wolfe; Matthew D. Johnson; C. John Ralph; R. Mark Brigham

2014-01-01

Nearctic-neotropic migrant birds need to replenish energy reserves during stopover periods to successfully complete their semiannual movements. In this study we used linear models to examine the habitat use of 11 migrant species in northeastern Costa Rica to better understand the influence of food and structural resources on the presence of birds during stopover...

Investigations of migratory birds during operation of Horns Rev offshore wind farm. Annual status report 2004

Energy Technology Data Exchange (ETDEWEB)

Kjaer Christensen, T.; Hounisen, J.P. [NERI, Dept. of Wildlife Ecology and Biodiversity, Roskilde (Denmark)

2005-07-01

The aim of the project is to assess the collision risk between birds and wind turbines at the Horns Rev wind farm. The study focused on describing bird movements in relation to the wind farm and to identify the species-specific behavioural responses towards the wind turbines shown by migrating and staging bird species. The study was based on data from spring 2004. The Horns Rev area lies in a region known to be of importance for substantial water bird migration as well as holding internationally important numbers of several wintering and staging water bird species. (au)

Investigations of migratory birds during operation of Horns Rev offshore wind farm. Annual status report 2004

International Nuclear Information System (INIS)

Kjaer Christensen, T.; Hounisen, J.P.

2005-01-01

The aim of the project is to assess the collision risk between birds and wind turbines at the Horns Rev wind farm. The study focused on describing bird movements in relation to the wind farm and to identify the species-specific behavioural responses towards the wind turbines shown by migrating and staging bird species. The study was based on data from spring 2004. The Horns Rev area lies in a region known to be of importance for substantial water bird migration as well as holding internationally important numbers of several wintering and staging water bird species. (au)

Real time eye tracking using Kalman extended spatio-temporal context learning

Science.gov (United States)

Munir, Farzeen; Minhas, Fayyaz ul Amir Asfar; Jalil, Abdul; Jeon, Moongu

2017-06-01

Real time eye tracking has numerous applications in human computer interaction such as a mouse cursor control in a computer system. It is useful for persons with muscular or motion impairments. However, tracking the movement of the eye is complicated by occlusion due to blinking, head movement, screen glare, rapid eye movements, etc. In this work, we present the algorithmic and construction details of a real time eye tracking system. Our proposed system is an extension of Spatio-Temporal context learning through Kalman Filtering. Spatio-Temporal Context Learning offers state of the art accuracy in general object tracking but its performance suffers due to object occlusion. Addition of the Kalman filter allows the proposed method to model the dynamics of the motion of the eye and provide robust eye tracking in cases of occlusion. We demonstrate the effectiveness of this tracking technique by controlling the computer cursor in real time by eye movements.

Birds of a feather? Food and agricultural risk governance of avian influenza in different EU Member States

NARCIS (Netherlands)

Krom, de M.P.M.M.

2009-01-01

From 2005 onwards, highly pathogenic avian influenza (bird flu) spread towards and eventually within Europe via different border-crossing flows, including those of wild birds and agricultural trade. Fear existed that via such movements, the virus would disseminate into and across territorially-based

Deriving Animal Movement Behaviors Using Movement Parameters Extracted from Location Data

Directory of Open Access Journals (Sweden)

Maryam Teimouri

2018-02-01

Full Text Available We present a methodology for distinguishing between three types of animal movement behavior (foraging, resting, and walking based on high-frequency tracking data. For each animal we quantify an individual movement path. A movement path is a temporal sequence consisting of the steps through space taken by an animal. By selecting a set of appropriate movement parameters, we develop a method to assess movement behavioral states, reflected by changes in the movement parameters. The two fundamental tasks of our study are segmentation and clustering. By segmentation, we mean the partitioning of the trajectory into segments, which are homogeneous in terms of their movement parameters. By clustering, we mean grouping similar segments together according to their estimated movement parameters. The proposed method is evaluated using field observations (done by humans of movement behavior. We found that on average, our method agreed with the observational data (ground truth at a level of 80.75% ± 5.9% (SE.

Computer-monitored radionuclide tracking of three-dimensional mandibular movements. Part II: experimental setup and preliminary results - Posselt diagram

Energy Technology Data Exchange (ETDEWEB)

Salomon, J.A.; Waysenson, B.D.; Warshaw, B.D.

1979-04-01

This article described a new method to track mandibular movements using a computer-assisted radionuclide kinematics technique. The usefulness of various image-enhancement techniques is discussed, and the reproduction of physiologic displacements is shown. Vertical, lateral, and protrusive envelopes of motion of a point on a tooth of a complete denture mounted on a semiadjustable articulator were measured. A demonstrative example of the validity of this approach is reproducing the motion of the dental point, which clearly evidences the Posselt diagram.

Fall detection in the elderly by head-tracking

OpenAIRE

Yu, Miao; Naqvi, Syed Mohsen; Chambers, Jonathan

2009-01-01

In the paper, we propose a fall detection method based on head tracking within a smart home environment equipped with video cameras. A motion history image and code-book background subtraction are combined to determine whether large movement occurs within the scene. Based on the magnitude of the movement information, particle filters with different state models are used to track the head. The head tracking procedure is performed in two video streams taken bytwoseparatecamerasandthree-dimension...

Effects of satellite transmitters on captive and wild mallards

Science.gov (United States)

Kesler, Dylan C.; Raedeke, Andrew H.; Foggia, Jennifer R.; Beatty, William S.; Webb, Elisabeth B.; Humburg, Dale D.; Naylor, Luke W.

2014-01-01

Satellite telemetry has become a leading method for studying large-scale movements and survival in birds, yet few have addressed potential effects of the larger and heavier tracking equipment on study subjects. We simultaneously evaluated effects of satellite telemetry equipment on captive and wild mallards (Anas platyrhynchos) to assess impacts on behavior, body mass, and movement. We randomly assigned 55 captive ducks to one of 3 treatment groups, including a standard body harness group, a modified harness group, and a control group. Ducks in the control group were not fitted with equipment, whereas individuals in the other 2 groups were fitted with dummy transmitters attached with a Teflon ribbon harness or with a similar harness constructed of nylon cord. At the conclusion of the 14-week captive study, mean body mass of birds in the control group was 40–105 g (95% CI) greater than birds with standard harnesses, and 28–99 g (95% CI) greater than birds with modified harnesses. Further, results of focal behavior observations indicated ducks with transmitters were less likely to be in water than control birds. We also tested whether movements of wild birds marked with a similar Teflon harness satellite transmitter aligned with population movements reported by on-the-ground observers who indexed local abundances of mid-continent mallards throughout the non-breeding period. Results indicated birds marked with satellite transmitters moved concurrently with the larger unmarked population. Our results have broad implications for field research and suggest that investigators should consider potential for physiological and behavioral effects brought about by tracking equipment. Nonetheless, results from wild ducks indicate satellite telemetry has the potential to provide useful movement data.

Performance test and verification of an off-the-shelf automated avian radar tracking system.

Science.gov (United States)

May, Roel; Steinheim, Yngve; Kvaløy, Pål; Vang, Roald; Hanssen, Frank

2017-08-01

Microwave radar is an important tool for observation of birds in flight and represents a tremendous increase in observation capability in terms of amount of surveillance space that can be covered at relatively low cost. Based on off-the-shelf radar hardware, automated radar tracking systems have been developed for monitoring avian movements. However, radar used as an observation instrument in biological research has its limitations that are important to be aware of when analyzing recorded radar data. This article describes a method for exploring the detection capabilities of a dedicated short-range avian radar system used inside the operational Smøla wind-power plant. The purpose of the testing described was to find the maximum detection range for various sized birds, while controlling for the effects of flight tortuosity, flight orientation relative to the radar and ground clutter. The method was to use a dedicated test target in form of a remotely controlled unmanned aerial vehicle (UAV) with calibrated radar cross section (RCS), which enabled the design of virtually any test flight pattern within the area of interest. The UAV had a detection probability of 0.5 within a range of 2,340 m from the radar. The detection performance obtained by the RCS-calibrated test target (-11 dBm 2 , 0.08 m 2 RCS) was then extrapolated to find the corresponding performance of differently sized birds. Detection range depends on system sensitivity, the environment within which the radar is placed and the spatial distribution of birds. The avian radar under study enables continuous monitoring of bird activity within a maximum range up to 2 km dependent on the size of the birds in question. While small bird species may be detected up to 0.5-1 km, larger species may be detected up to 1.5-2 km distance from the radar.

Eye tracking a comprehensive guide to methods and measures

CERN Document Server

Holmqvist, Kenneth; Andersson, Richard; Dewhurst, Richard; Jarodzka, Halszka; Weijer, Joost van de

2011-01-01

We make 3-5 eye movements per second, and these movements are crucial in helping us deal with the vast amounts of information we encounter in our everyday lives. In recent years, thanks to the development of eye tracking technology, there has been a growing interest in monitoring and measuring these movements, with a view to understanding how we attend to and process the visual information we encounter Eye tracking as a research tool is now more accessible than ever, and is growing in popularity amongst researchers from a whole host of different disciplines. Usability analysts, sports scientists, cognitive psychologists, reading researchers, psycholinguists, neurophysiologists, electrical engineers, and others, all have a vested interest in eye tracking for different reasons. The ability to record eye-movements has helped advance our science and led to technological innovations. However, the growth of eye tracking in recent years has also presented a variety of challenges - in particular the issue of how to d...

Arthropods and associated arthropod-borne diseases transmitted by migrating birds. The case of ticks and tick-borne pathogens.

Science.gov (United States)

Sparagano, Olivier; George, David; Giangaspero, Annunziata; Špitalská, Eva

2015-09-30

Geographic spread of parasites and pathogens poses a constant risk to animal health and welfare, particularly given that climate change is expected to potentially expand appropriate ranges for many key species. The spread of deleterious organisms via trade routes and human travelling is relatively closely controlled, though represents only one possible means of parasite/pathogen distribution. The transmission via natural parasite/pathogen movement between geographic locales, is far harder to manage. Though the extent of such movement may be limited by the relative inability of many parasites and pathogens to actively migrate, passive movement over long distances may still occur via migratory hosts. This paper reviews the potential role of migrating birds in the transfer of ectoparasites and pathogens between geographic locales, focusing primarily on ticks. Bird-tick-pathogen relationships are considered, and evidence provided of long-range parasite/pathogen transfer from one location to another during bird migration events. As shown in this paper not only many different arthropod species are carried by migrating birds but consequently these pests carry many different pathogens species which can be transmitted to the migrating birds or to other animal species when those arthropods are dropping during these migrations. Data available from the literature are provided highlighting the need to understand better dissemination paths and disease epidemiology. Copyright © 2015 Elsevier B.V. All rights reserved.

Spatiotemporal modelling of marine movement data using Template Model Builder (TMB)

DEFF Research Database (Denmark)

Auger-Méthé, Marie; Albertsen, Christoffer Moesgaard; Jonsen, Ian D.

2017-01-01

Tracking of marine animals has increased exponentially in the past decade, and the resulting data could lead to an in-depth understanding of the causes and consequences of movement in the ocean. However, most common marine tracking systems are associated with large measurement errors. Accounting...... tool for modelling marine movement data. We discuss how TMB’s potential reaches beyond marine movement studies...

Past, present and future of tourist tracking

Directory of Open Access Journals (Sweden)

Tatjana Thimm

2016-03-01

Full Text Available Purpose – The purpose of this paper is to find out tourism movement patterns via the tracking of tourists with the help of positioning systems like GPS in the rural area of the Lake Constance destination in Germany. In doing so past, present and future of tourist tracking is illustrated. Design/methodology/approach – The tracking is realized via common smartphones extended by an app, with dedicated sensors like position loggers and a survey. The three different approaches are applied in order to compare and cross-check results (triangulation of data and methods. Findings – Movement patterns turned out to be diverse and individualistic within the rural destination of Lake Constance and following an ants trail in sub-destinations like the city of Constance. Repeat visitors and first-time visitors alike always visit the bigger cities and main day-trip destinations of the Lake. A possible prediction tool enables new avenues of governing tourism movement patterns. Research limitations/implications – The tracking techniques can be developed further into the direction of “quantified self” using gamification in order to make the tracking app even more attractive. Practical implications – An algorithm-based prediction tool would offer new perspectives to the management of tourism movements. Social implications – Further research is needed to overcome the feeling of invasiveness of the app to allow tracking with that approach. Originality/value – This study is original and innovative because of the first-time use of a smartphone app in tourist tracking, the application on a rural destination and the conceptual description of a prediction tool.

Tracking the Poster Movement

DEFF Research Database (Denmark)

Christensen, Line Hjorth

2015-01-01

Summary: This article considers the display of posters as a distinctive activity and defining aspect of British modernism between the two wars, looking to a cardinal event, the Exhibition of British and Foreign Posters at the Victoria and Albert Museum in 1931. This manifestation was the first...... in the Museum to expose the poster-image as a medium in its own artistic, technical, historical and popular right; the article examines the event as a sign holding core characteristics of a ‘poster movement’ prevailing during the interwar years. The period made a varied scene for exhibitions promoting...... commercial and graphic design of various kinds of which British and Foreign Posters offers a particularly rich example. The exhibition attracted commercial, artistic and curatorial forces substantiating the idea of a movement, and approached commercial art from a perspective that raised new awareness towards...

Alabama ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, gulls, and terns...

Maryland ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, and gulls and...

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

Science.gov (United States)

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

Vegetation moderates impacts of tourism usage on bird communities along roads and hiking trails.

Science.gov (United States)

Wolf, Isabelle D; Hagenloh, Gerald; Croft, David B

2013-11-15

Bird communities inhabiting ecosystems adjacent to recreational tracks may be adversely affected by disturbance from passing tourism traffic, vehicle-related mortality, habitat alteration and modified biotic relationships such as the increase of strong competitors. This study investigated the effects of tourist usage of roads vs. hiking trails on bird communities in gorges of the Flinders Ranges, a popular South Australian tourist destination in the arid-lands. High tourist usage along roads decreased the individual abundance and species richness of birds relative to low usage trails. The decrease in species richness, though less pronounced, also occurred at high-usage sites along trails. Changes in the species response to recreational disturbance/impacts varied depending on the ecology of the species. Bigger, more competitive birds with a generalist diet were overrepresented at high-usage sites along roads and trails. Species using microhabitats in lower vegetation layers were more sensitive. However, structural and floristic complexity of vegetation was a more important factor influencing bird abundance than tourist usage. Sites with a better developed shrub and tree layer sustained higher species abundance and richer communities. Importantly, vegetation qualities moderated the negative effect of high usage on the individual abundance of birds along roads, to the extent that such an effect was absent at sites with the best developed shrub and tree layer. To protect avifauna along recreational tracks in arid-lands gorges, we recommend the closure of some gorges or sections for vehicle or any access. Further, open space particularly for camping needs to be minimized as it creates areas of high tourist usage with modified habitat that provides birds with little buffer from disturbance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Tracking a "facer's" behavior in a public plaza

DEFF Research Database (Denmark)

2014-01-01

The video shows the tracking of a "facer's" behavior in a public plaza using a thermal camera (non-privacy violating) and a visualization of the tracks in a space-time cube in a 3D GIS. The tracking data is used in my PhD project on Human Movement Patterns in Smart Cities. The recording and analy...... and analysis of the thermal video has been made in collaboration with Rikke Gade from the Visual Analytics of People Lab at Aalborg University.......The video shows the tracking of a "facer's" behavior in a public plaza using a thermal camera (non-privacy violating) and a visualization of the tracks in a space-time cube in a 3D GIS. The tracking data is used in my PhD project on Human Movement Patterns in Smart Cities. The recording...

Avian Information Systems: Developing Web-Based Bird Avoidance Models

Directory of Open Access Journals (Sweden)

Judy Shamoun-Baranes

2008-12-01

Full Text Available Collisions between aircraft and birds, so-called "bird strikes," can result in serious damage to aircraft and even in the loss of lives. Information about the distribution of birds in the air and on the ground can be used to reduce the risk of bird strikes and their impact on operations en route and in and around air fields. Although a wealth of bird distribution and density data is collected by numerous organizations, these data are not readily available nor interpretable by aviation. This paper presents two national efforts, one in the Netherlands and one in the United States, to develop bird avoidance nodels for aviation. These models integrate data and expert knowledge on bird distributions and migratory behavior to provide hazard maps in the form of GIS-enabled Web services. Both models are in operational use for flight planning and flight alteration and for airfield and airfield vicinity management. These models and their presentation on the Internet are examples of the type of service that would be very useful in other fields interested in species distribution and movement information, such as conservation, disease transmission and prevention, or assessment and mitigation of anthropogenic risks to nature. We expect that developments in cyber-technology, a transition toward an open source philosophy, and higher demand for accessible biological data will result in an increase in the number of biological information systems available on the Internet.

Testing for associations between hematozoa infection and mercury in wading bird nestlings.

Science.gov (United States)

Bryan, A Lawrence; Love, Cara N; Mills, Gary L; Borkhataria, Rena R; Lance, Stacey L

2015-01-01

Several wading bird species in the southeastern US have a history of infection by hematozoa/avian malaria as well as mercury accumulation through their diet, and thus may be exposed to two, generally sublethal, yet chronic, stressors. We analyzed nestling wading birds (n = 171) of varying size and trophic position from the southeastern US, and a smaller sample (n = 23) of older, free-ranging birds, to look for potential interrelationships between infection by hematozoa and mercury (Hg) uptake. Only one nestling was PCR positive for hematozoa (Plasmodium/Haemoproteus) whereas nine (39%) of the older wading birds were positive. Sequencing indicated that both nestling and adult positives were infected with Plasmodium. Given the low infection rate of the nestlings, there was no association between Hg and malaria. The older birds exhibited a possible malaria/Hg association, but it may be confounded by their greater potential exposure period and large-scale movements.

9 CFR 82.6 - Interstate movement of dead birds and dead poultry from a quarantined area.

Science.gov (United States)

2010-01-01

... provided in paragraph (b) of this section for dressed carcasses, dead birds and dead poultry, including any... poultry at the destination listed on the permit required by paragraph (a)(1) of this section. (b) Dressed... quarantined area only if: (1) The dressed carcasses are from birds or poultry that were slaughtered in a...

A Model for Nationwide Patient Tracking

Science.gov (United States)

2009-09-01

SUBJECT TERMS Patient Tracking, Public Health, Emergency Medical Services, Patient Movement, Evacuation, Public Health Preparedness 16. PRICE CODE 17...Emergency Medical Services................................................................................................19 2. Ideal Patient Tracking... Medical Services ............................................................36 a. Patient Flow in Field-Based Casualty Care—Current Process

Radar ornithology and the conservation of migratory birds

Science.gov (United States)

Sidney A. Gauthreaux; Carroll G. Belser

2005-01-01

It is possible to study with surveillance radar the movements of migrating birds in the atmosphere at different spatial scales. At a spatial scale within a range of 6 kilometers, high-resolution, 3-centimeter wavelength surveillance radar (e.g. BIRDRAD) can detect the departure of migrants from different types of habitat within a few kilometers of the radar. The radar...

Energy beyond food: foraging theory informs time spent in thermals by a large soaring bird.

Directory of Open Access Journals (Sweden)

Emily L C Shepard

Full Text Available Current understanding of how animals search for and exploit food resources is based on microeconomic models. Although widely used to examine feeding, such constructs should inform other energy-harvesting situations where theoretical assumptions are met. In fact, some animals extract non-food forms of energy from the environment, such as birds that soar in updraughts. This study examined whether the gains in potential energy (altitude followed efficiency-maximising predictions in the world's heaviest soaring bird, the Andean condor (Vultur gryphus. Animal-attached technology was used to record condor flight paths in three-dimensions. Tracks showed that time spent in patchy thermals was broadly consistent with a strategy to maximise the rate of potential energy gain. However, the rate of climb just prior to leaving a thermal increased with thermal strength and exit altitude. This suggests higher rates of energetic gain may not be advantageous where the resulting gain in altitude would lead to a reduction in the ability to search the ground for food. Consequently, soaring behaviour appeared to be modulated by the need to reconcile differing potential energy and food energy distributions. We suggest that foraging constructs may provide insight into the exploitation of non-food energy forms, and that non-food energy distributions may be more important in informing patterns of movement and residency over a range of scales than previously considered.

Cicadas impact bird communication in a noisy tropical rainforest

Science.gov (United States)

Hall, Robert; Ray, William; Beck, Angela; Zook, James

2015-01-01

Many animals communicate through acoustic signaling, and “acoustic space” may be viewed as a limited resource that organisms compete for. If acoustic signals overlap, the information in them is masked, so there should be selection toward strategies that reduce signal overlap. The extent to which animals are able to partition acoustic space in acoustically diverse habitats such as tropical forests is poorly known. Here, we demonstrate that a single cicada species plays a major role in the frequency and timing of acoustic communication in a neotropical wet forest bird community. Using an automated acoustic monitor, we found that cicadas vary the timing of their signals throughout the day and that the frequency range and timing of bird vocalizations closely track these signals. Birds significantly avoid temporal overlap with cicadas by reducing and often shutting down vocalizations at the onset of cicada signals that utilize the same frequency range. When birds do vocalize at the same time as cicadas, the vocalizations primarily occur at nonoverlapping frequencies with cicada signals. Our results greatly improve our understanding of the community dynamics of acoustic signaling and reveal how patterns in biotic noise shape the frequency and timing of bird vocalizations in tropical forests. PMID:26023277

A novel strong tracking finite-difference extended Kalman filter for nonlinear eye tracking

Institute of Scientific and Technical Information of China (English)

ZHANG ZuTao; ZHANG JiaShu

2009-01-01

Non-Intrusive methods for eye tracking are Important for many applications of vision-based human computer interaction. However, due to the high nonlinearity of eye motion, how to ensure the robust-ness of external interference and accuracy of eye tracking poses the primary obstacle to the integration of eye movements into today's interfaces. In this paper, we present a strong tracking finite-difference extended Kalman filter algorithm, aiming to overcome the difficulty In modeling nonlinear eye tracking. In filtering calculation, strong tracking factor is introduced to modify a priori covariance matrix and im-prove the accuracy of the filter. The filter uses finite-difference method to calculate partial derivatives of nonlinear functions for eye tracking. The latest experimental results show the validity of our method for eye tracking under realistic conditions.

Tracking progress toward EU Biodiversity Strategy targets: EU policy effects in preserving its common farmland birds

Czech Academy of Sciences Publication Activity Database

Gamero, A.; Brotons, L.; Brunner, A.; Foppen, R.; Fornasari, L.; Gregory, R. D.; Herrando, S.; Hořák, D.; Jiguet, F.; Kmecl, P.; Lehikoinen, A.; Lindström, Å.; Paquet, J. Y.; Reif, J.; Sirkiä, P. M.; Škorpilová, J.; van Strien, A.; Szép, T.; Telenský, Tomáš; Teufelbauer, N.; Trautmann, S.; Van Turnhout, C. A. M.; Vermouzek, Z.; Vikstrøm, T.; Voříšek, P.

2017-01-01

Roč. 10, č. 4 (2017), s. 395-402 ISSN 1755-263X Institutional support: RVO:68081766 Keywords : Agricultural intensification * Agrienvironmental schemes * Bird monitoring * Birds directive * Common agriculture policy * Natura 2000 * SPA Subject RIV: EG - Zoology OBOR OECD: Biodiversity conservation Impact factor: 7.020, year: 2016

AndroBird - ein neues GPS-basiertes Erfassungssystem für Vögel, Amphibien und Reptilien für Android-Smartphones

OpenAIRE

Braun, Michael; Braun, Andreas; Heine, Georg

2013-01-01

AndroBird is a new freeware app (Google Playstore) for logging of birds, amphibians and reptiles. It works with Android Smartphones Vers. 2.1 and beyond. Based on GPS (Global Positioning System), observations in the field are logged and later exported to MiniAvi, a powerful ornithological software for Windows. Major functions of AndroBird include species lists for birds, amphibians and reptiles, GPS tracking (only possible with GPS-Smartphones) using heading and distance (up to 10 km) for pos...

Columbia River ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, diving birds, seabirds, passerine birds, gulls, and terns in...

Postbreeding elevational movements of western songbirds in Northern California and Southern Oregon.

Science.gov (United States)

Wiegardt, Andrew; Wolfe, Jared; Ralph, C John; Stephens, Jaime L; Alexander, John

2017-10-01

Migratory species employ a variety of strategies to meet energetic demands of postbreeding molt. As such, at least a few species of western Neotropical migrants are known to undergo short-distance upslope movements to locations where adults molt body and flight feathers (altitudinal molt migration). Given inherent difficulties in measuring subtle movements of birds occurring in western mountains, we believe that altitudinal molt migration may be a common yet poorly documented phenomenon. To examine prevalence of altitudinal molt migration, we used 29 years of bird capture data in a series of linear mixed-effect models for nine commonly captured species that breed in northern California and southern Oregon. Candidate models were formulated a priori to examine whether elevation and distance from the coast can be used to predict abundance of breeding and molting birds. Our results suggest that long-distance migrants such as Orange-crowned Warbler ( Oreothlypis celata ) moved higher in elevation and Audubon's Warbler ( Setophaga coronata ) moved farther inland to molt after breeding. Conversely, for resident and short-distance migrants, we found evidence that birds either remained on the breeding grounds until they finished molting, such as Song Sparrow ( Melospiza melodia ) or made small downslope movements, such as American Robin ( Turdus migratorius ). We conclude that altitudinal molt migration may be a common, variable, and complex behavior among western songbird communities and is related to other aspects of a species' natural history, such as migratory strategy.

Diffusion of the Digital Health Self-Tracking Movement in Canada: Results of a National Survey

Science.gov (United States)

Leaver, Chad; Bourget, Claire

2018-01-01

Background With the ever-increasing availability of mobile apps, consumer wearables, and smart medical devices, more and more individuals are self-tracking and managing their personal health data. Objective The aim of this study was to investigate the diffusion of the digital self-tracking movement in Canada. It provides a comprehensive, yet detailed account of this phenomenon. It examines the profile of digital self-trackers, traditional self-trackers, and nontrackers, further investigating the primary motivations for self-tracking and reasons for nontracking; barriers to adoption of connected care technologies; users’ appreciation of their self-tracking devices, including what they perceive to be the main benefits; factors that influence people’s intention to continue using connected care technologies in the future; and the reasons for usage discontinuance. Methods We conducted an online survey with a sample of 4109 Canadian adults, one of the largest ever. To ensure a representative sample, quota method was used (gender, age), following stratification by region. The maximum margin of error is estimated at 1.6%, 19 times out of 20. Results Our findings reveal that 66.20% (2720/4109) of our respondents regularly self-track one or more aspects of their health. About one in 4 respondents (1014/4109, 24.68%) currently owns a wearable or smart medical device, and 57.20% (580/1014) use their devices on a regular basis for self-tracking purposes. Digital self-trackers are typically young or mature adults, healthy, employed, university educated, with an annual family income of over $80,000 CAD. The most popular reported device is the fitness tracker or smartwatch that can capture a range of parameters. Currently, mobile apps and digital self-tracking devices are mainly used to monitor physical activity (856/1669, 51.13%), nutrition (545/1669, 32.65%), sleep patterns (482/1669, 28.88%) and, to a much lesser extent, cardiovascular and pulmonary biomarkers (215/1669, 12

Prevalence of avian influenza virus in wild birds before and after the HPAI H5N8 outbreak in 2014 in South Korea.

Science.gov (United States)

Shin, Jeong-Hwa; Woo, Chanjin; Wang, Seung-Jun; Jeong, Jipseol; An, In-Jung; Hwang, Jong-Kyung; Jo, Seong-Deok; Yu, Seung Do; Choi, Kyunghee; Chung, Hyen-Mi; Suh, Jae-Hwa; Kim, Seol-Hee

2015-07-01

Since 2003, highly pathogenic avian influenza (HPAI) virus outbreaks have occurred five times in Korea, with four HPAI H5N1 outbreaks and one HPAI H5N8 outbreak. Migratory birds have been suggested to be the first source of HPAI in Korea. Here, we surveyed migratory wild birds for the presence of AI and compared regional AI prevalence in wild birds from September 2012 to April 2014 for birds having migratory pathways in South Korea. Finally, we investigated the prevalence of AI in migratory birds before and after HPAI H5N8 outbreaks. Overall, we captured 1617 migratory wild birds, while 18,817 feces samples and 74 dead birds were collected from major wild bird habitats. A total of 21 HPAI viruses were isolated from dead birds, and 86 low pathogenic AI (LPAI) viruses were isolated from captured birds and from feces samples. Spatiotemporal distribution analysis revealed that AI viruses were spread southward until December, but tended to shift north after January, consistent with the movement of migratory birds in South Korea. Furthermore, we found that LPAI virus prevalences within wild birds were notably higher in 2013-2014 than the previous prevalence during the northward migration season. The data from our study demonstrate the importance of the surveillance of AI in wild birds. Future studies including in-depth genetic analysis in combination with evaluation of the movement and ecology of migratory birds might help us to bridge the gaps in our knowledge and better explain, predict, and ultimately prevent future HPAI outbreaks.

Multiple objects tracking in fluorescence microscopy.

Science.gov (United States)

Kalaidzidis, Yannis

2009-01-01

Many processes in cell biology are connected to the movement of compact entities: intracellular vesicles and even single molecules. The tracking of individual objects is important for understanding cellular dynamics. Here we describe the tracking algorithms which have been developed in the non-biological fields and successfully applied to object detection and tracking in biological applications. The characteristics features of the different algorithms are compared.

The role of kopjes in bird species' conservation within an agricultural ...

African Journals Online (AJOL)

Just west of the Greater Serengeti Ecosystem (GSE), an area defined by movements ... assumed that similar natural savanna habitat found inside the present GRE previously ..... the kopjes attracted Speckled Pigeon Columba guinea and White-fronted Barbet Lybius .... Birds of Africa South of the Sahara: Second Edition.

Olfactory lateralization in homing pigeons: a GPS study on birds released with unilateral olfactory inputs.

Science.gov (United States)

Gagliardo, Anna; Filannino, Caterina; Ioalè, Paolo; Pecchia, Tommaso; Wikelski, Martin; Vallortigara, Giorgio

2011-02-15

A large body of evidence has shown that pigeons rely on an olfactory-based navigational map when homing from unfamiliar locations. Previous studies on pigeons released with one nostril occluded highlighted an asymmetry in favour of the right nostril, particularly concerning the initial orientation performance of naïve birds. Nevertheless, all pigeons experiencing only unilateral olfactory input showed impaired homing, regardless of the side of the occluded nostril. So far this phenomenon has been documented only by observing the birds' vanishing bearings. In the present work we recorded the flight tracks of pigeons with previous homing experience equipped with a GPS data logger and released from an unfamiliar location with the right or the left nostril occluded. The analysis of the tracks revealed that the flight path of the birds with the right nostril occluded was more tortuous than that of unmanipulated controls. Moreover, the pigeons smelling with the left nostril interrupted their journey significantly more frequently and displayed more exploratory activity than the control birds, e.g. during flights around a stopover site. These data suggest a more important involvement of the right olfactory system in processing the olfactory information needed for the operation of the navigational map.

Satellite and acoustic tracking device

KAUST Repository

Berumen, Michael L.

2014-02-20

The present invention relates a method and device for tracking movements of marine animals or objects in large bodies of water and across significant distances. The method and device can track an acoustic transmitter attached to an animal or object beneath the ocean surface by employing an unmanned surface vessel equipped with a hydrophone array and GPS receiver.

Satellite and acoustic tracking device

KAUST Repository

Berumen, Michael L.; De la Torre, Pedro

2014-01-01

The present invention relates a method and device for tracking movements of marine animals or objects in large bodies of water and across significant distances. The method and device can track an acoustic transmitter attached to an animal or object beneath the ocean surface by employing an unmanned surface vessel equipped with a hydrophone array and GPS receiver.

Active sensing via movement shapes spatiotemporal patterns of sensory feedback.

Science.gov (United States)

Stamper, Sarah A; Roth, Eatai; Cowan, Noah J; Fortune, Eric S

2012-05-01

Previous work has shown that animals alter their locomotor behavior to increase sensing volumes. However, an animal's own movement also determines the spatial and temporal dynamics of sensory feedback. Because each sensory modality has unique spatiotemporal properties, movement has differential and potentially independent effects on each sensory system. Here we show that weakly electric fish dramatically adjust their locomotor behavior in relation to changes of modality-specific information in a task in which increasing sensory volume is irrelevant. We varied sensory information during a refuge-tracking task by changing illumination (vision) and conductivity (electroreception). The gain between refuge movement stimuli and fish tracking responses was functionally identical across all sensory conditions. However, there was a significant increase in the tracking error in the dark (no visual cues). This was a result of spontaneous whole-body oscillations (0.1 to 1 Hz) produced by the fish. These movements were costly: in the dark, fish swam over three times further when tracking and produced more net positive mechanical work. The magnitudes of these oscillations increased as electrosensory salience was degraded via increases in conductivity. In addition, tail bending (1.5 to 2.35 Hz), which has been reported to enhance electrosensory perception, occurred only during trials in the dark. These data show that both categories of movements - whole-body oscillations and tail bends - actively shape the spatiotemporal dynamics of electrosensory feedback.

Thinking with birds: Mary Elizabeth Barber's advocacy for gender equality in ornithology

Directory of Open Access Journals (Sweden)

Tanja Hammel

Full Text Available This article explores parts of the first South African woman ornithologist's life and work. It concerns itself with the micro-politics of Mary Elizabeth Barber's knowledge of birds from the 1860s to the mid-1880s. Her work provides insight into contemporary scientific practices, particularly the importance of cross-cultural collaboration. I foreground how she cultivated a feminist Darwinism in which birds served as corroborative evidence for female selection and how she negotiated gender equality in her ornithological work. She did so by constructing local birdlife as a space of gender equality. While male ornithologists naturalised and reinvigorated Victorian gender roles in their descriptions and depictions of birds, she debunked them and stressed the absence of gendered spheres in bird life. She emphasised the female and male birds' collaboration and gender equality that she missed in Victorian matrimony, an institution she harshly criticised. Reading her work against the background of her life story shows how her personal experiences as wife and mother as well as her observation of settler society informed her view on birds, and vice versa. Through birds she presented alternative relationships to matrimony. Her protection of insectivorous birds was at the same time an attempt to stress the need for a New Woman, an aspect that has hitherto been overlooked in studies of the transnational anti-plumage movement.

The effect of changes in habitat conditions on the movement of juvenile Snail Kites Rostrhamus sociabilis

Science.gov (United States)

Bowling, Andrea C.; Martin, Julien; Kitchens, Wiley M.

2012-01-01

The degradation of habitats due to human activities is a major topic of interest for the conservation and management of wild populations. There is growing evidence that the Florida Everglades ecosystem continues to suffer from habitat degradation. After a period of recovery in the 1990s, the Snail Kite Rostrhamus sociabilis population suffered a substantial decline in 2001 and has not recovered since. Habitat degradation has been suggested as one of the primary reasons for this lack of recovery. As a consequence of the continued degradation of the Everglades, we hypothesized that this would have led to increased movement of juvenile Kites over time, as a consequence of the need to find more favourable habitat. We used multistate mark-recapture models to compare between-site movement probabilities of juvenile Snail Kites in the 1990s (1992–95; which corresponds to the period before the decline) and 2000s (2003–06; after the decline). Our analyses were based on an extensive radiotelemetry study (266 birds tracked monthly over the entire state of Florida for a total period of 6 years) and considered factors such as sex and age of marked individuals. There was evidence of increased movement of juvenile Snail Kites during the post-decline period from most of the wetland regions used historically by Kites. Higher movement rates may contribute to an increase in the probability of mortality of young individuals and could contribute to the observed declines.

Study on bird's & insect's wing aerodynamics and comparison of its analytical value with standard airfoil

Science.gov (United States)

Ali, Md. Nesar; Alam, Mahbubul; Hossain, Md. Abed; Ahmed, Md. Imteaz

2017-06-01

Flight is the main mode of locomotion used by most of the world's bird & insect species. This article discusses the mechanics of bird flight, with emphasis on the varied forms of bird's & insect's wings. The fundamentals of bird flight are similar to those of aircraft. Flying animals flap their wings to generate lift and thrust as well as to perform remarkable maneuvers with rapid accelerations and decelerations. Insects and birds provide illuminating examples of unsteady aerodynamics. Lift force is produced by the action of air flow on the wing, which is an airfoil. The airfoil is shaped such that the air provides a net upward force on the wing, while the movement of air is directed downward. Additional net lift may come from airflow around the bird's & insect's body in some species, especially during intermittent flight while the wings are folded or semi-folded. Bird's & insect's flight in nature are sub-divided into two stages. They are Unpowered Flight: Gliding and Soaring & Powered Flight: Flapping. When gliding, birds and insects obtain both a vertical and a forward force from their wings. When a bird & insect flaps, as opposed to gliding, its wings continue to develop lift as before, but the lift is rotated forward to provide thrust, which counteracts drag and increases its speed, which has the effect of also increasing lift to counteract its weight, allowing it to maintain height or to climb. Flapping flight is more complicated than flight with fixed wings because of the structural movement and the resulting unsteady fluid dynamics. Flapping involves two stages: the down-stroke, which provides the majority of the thrust, and the up-stroke, which can also (depending on the bird's & insect's wings) provide some thrust. Most kinds of bird & insect wing can be grouped into four types, with some falling between two of these types. These types of wings are elliptical wings, high speed wings, high aspect ratio wings and soaring wings with slots. Hovering is used

Mousetrap: An integrated, open-source mouse-tracking package.

Science.gov (United States)

Kieslich, Pascal J; Henninger, Felix

2017-10-01

Mouse-tracking - the analysis of mouse movements in computerized experiments - is becoming increasingly popular in the cognitive sciences. Mouse movements are taken as an indicator of commitment to or conflict between choice options during the decision process. Using mouse-tracking, researchers have gained insight into the temporal development of cognitive processes across a growing number of psychological domains. In the current article, we present software that offers easy and convenient means of recording and analyzing mouse movements in computerized laboratory experiments. In particular, we introduce and demonstrate the mousetrap plugin that adds mouse-tracking to OpenSesame, a popular general-purpose graphical experiment builder. By integrating with this existing experimental software, mousetrap allows for the creation of mouse-tracking studies through a graphical interface, without requiring programming skills. Thus, researchers can benefit from the core features of a validated software package and the many extensions available for it (e.g., the integration with auxiliary hardware such as eye-tracking, or the support of interactive experiments). In addition, the recorded data can be imported directly into the statistical programming language R using the mousetrap package, which greatly facilitates analysis. Mousetrap is cross-platform, open-source and available free of charge from https://github.com/pascalkieslich/mousetrap-os .

Improved nano-particle tracking analysis

International Nuclear Information System (INIS)

Walker, John G

2012-01-01

Nano-particle tracking is a method to estimate a particle size distribution by tracking the movements of individual particles, using multiple images of particles moving under Brownian motion. A novel method to recover a particle size distribution from nano-particle tracking data is described. Unlike a simple histogram-based method, the method described is able to account for the finite number of steps in each particle track and consequently for the measurement uncertainty in the step-length data. Computer simulation and experimental results are presented to demonstrate the performance of the approach compared with the current method. (paper)

Developing and Integrating Advanced Movement Features Improves Automated Classification of Ciliate Species.

Science.gov (United States)

Soleymani, Ali; Pennekamp, Frank; Petchey, Owen L; Weibel, Robert

2015-01-01

Recent advances in tracking technologies such as GPS or video tracking systems describe the movement paths of individuals in unprecedented details and are increasingly used in different fields, including ecology. However, extracting information from raw movement data requires advanced analysis techniques, for instance to infer behaviors expressed during a certain period of the recorded trajectory, or gender or species identity in case data is obtained from remote tracking. In this paper, we address how different movement features affect the ability to automatically classify the species identity, using a dataset of unicellular microbes (i.e., ciliates). Previously, morphological attributes and simple movement metrics, such as speed, were used for classifying ciliate species. Here, we demonstrate that adding advanced movement features, in particular such based on discrete wavelet transform, to morphological features can improve classification. These results may have practical applications in automated monitoring of waste water facilities as well as environmental monitoring of aquatic systems.

Diffusion of the Digital Health Self-Tracking Movement in Canada: Results of a National Survey.

Science.gov (United States)

Paré, Guy; Leaver, Chad; Bourget, Claire

2018-05-02

With the ever-increasing availability of mobile apps, consumer wearables, and smart medical devices, more and more individuals are self-tracking and managing their personal health data. The aim of this study was to investigate the diffusion of the digital self-tracking movement in Canada. It provides a comprehensive, yet detailed account of this phenomenon. It examines the profile of digital self-trackers, traditional self-trackers, and nontrackers, further investigating the primary motivations for self-tracking and reasons for nontracking; barriers to adoption of connected care technologies; users' appreciation of their self-tracking devices, including what they perceive to be the main benefits; factors that influence people's intention to continue using connected care technologies in the future; and the reasons for usage discontinuance. We conducted an online survey with a sample of 4109 Canadian adults, one of the largest ever. To ensure a representative sample, quota method was used (gender, age), following stratification by region. The maximum margin of error is estimated at 1.6%, 19 times out of 20. Our findings reveal that 66.20% (2720/4109) of our respondents regularly self-track one or more aspects of their health. About one in 4 respondents (1014/4109, 24.68%) currently owns a wearable or smart medical device, and 57.20% (580/1014) use their devices on a regular basis for self-tracking purposes. Digital self-trackers are typically young or mature adults, healthy, employed, university educated, with an annual family income of over $80,000 CAD. The most popular reported device is the fitness tracker or smartwatch that can capture a range of parameters. Currently, mobile apps and digital self-tracking devices are mainly used to monitor physical activity (856/1669, 51.13%), nutrition (545/1669, 32.65%), sleep patterns (482/1669, 28.88%) and, to a much lesser extent, cardiovascular and pulmonary biomarkers (215/1669, 12.88%), medication intake (126/1669, 7

Horizontal movements of Atlantic blue marlin (Makaira nigricans) in the Gulf of Mexico

Science.gov (United States)

Kraus, R.T.; Wells, R.J.D.; Rooker, J.R.

2011-01-01

We examined movements of Atlantic blue marlin (Makaira nigricans) from the Gulf of Mexico based upon 42 pop-up archival transmitting (PAT) tags. Long deployments (including one 334-day track) revealed diverse movement patterns within the Gulf of Mexico. North-south seasonal changes in blue marlin distribution showed strong correspondence with established seasonal patterns of sea surface temperature and primary production. During the summer spawning season, blue marlin utilized outer shelf and shelf edge waters in the northern Gulf of Mexico, and longer duration tracks indicated overwintering habitats in the Bay of Campeche. Egress occurred throughout the year and was difficult to determine because some tracks ended in the Straits of Florida (n = 3) while other tracks recorded movement through it or the Yucatan Channel (n = 4). Our results indicate that Atlantic blue marlin have a more restricted geographic range of habitats than previously recognized and that the Gulf of Mexico provides spatially dynamic suitable habitat that is utilized year-round through seasonal movements. ?? 2011 Springer-Verlag.

Birds of Two Oceans? Trans-Andean and Divergent Migration of Black Skimmers (Rynchops niger cinerascens) from the Peruvian Amazon.

Science.gov (United States)

Davenport, Lisa C; Goodenough, Katharine S; Haugaasen, Torbjørn

2016-01-01

Seasonal flooding compels some birds that breed in aquatic habitats in Amazonia to undertake annual migrations, yet we know little about how the complex landscape of the Amazon region is used seasonally by these species. The possibility of trans-Andes migration for Amazonian breeding birds has largely been discounted given the high geographic barrier posed by the Andean Cordillera and the desert habitat along much of the Pacific Coast. Here we demonstrate a trans-Andes route for Black Skimmers (Rynchops niger cinerascens) breeding on the Manu River (in the lowlands of Manu National Park, Perú), as well as divergent movement patterns both regionally and across the continent. Of eight skimmers tracked with satellite telemetry, three provided data on their outbound migrations, with two crossing the high Peruvian Andes to the Pacific. A third traveled over 1800 km to the southeast before transmissions ended in eastern Paraguay. One of the two trans-Andean migrants demonstrated a full round-trip migration back to its tagging location after traveling down the Pacific Coast from latitude 9° South to latitude 37° S, spending the austral summer in the Gulf of Arauco, Chile. This is the first documentation of a trans-Andes migration observed for any bird breeding in lowland Amazonia. To our knowledge, this research also documents the first example of a tropical-breeding waterbird migrating out of the tropics to spend the non-breeding season in the temperate summer, this being the reverse pattern with respect to seasonality for austral migrants in general.

Automated Thermal Image Processing for Detection and Classification of Birds and Bats - FY2012 Annual Report

Energy Technology Data Exchange (ETDEWEB)

Duberstein, Corey A.; Matzner, Shari; Cullinan, Valerie I.; Virden, Daniel J.; Myers, Joshua R.; Maxwell, Adam R.

2012-09-01

Surveying wildlife at risk from offshore wind energy development is difficult and expensive. Infrared video can be used to record birds and bats that pass through the camera view, but it is also time consuming and expensive to review video and determine what was recorded. We proposed to conduct algorithm and software development to identify and to differentiate thermally detected targets of interest that would allow automated processing of thermal image data to enumerate birds, bats, and insects. During FY2012 we developed computer code within MATLAB to identify objects recorded in video and extract attribute information that describes the objects recorded. We tested the efficiency of track identification using observer-based counts of tracks within segments of sample video. We examined object attributes, modeled the effects of random variability on attributes, and produced data smoothing techniques to limit random variation within attribute data. We also began drafting and testing methodology to identify objects recorded on video. We also recorded approximately 10 hours of infrared video of various marine birds, passerine birds, and bats near the Pacific Northwest National Laboratory (PNNL) Marine Sciences Laboratory (MSL) at Sequim, Washington. A total of 6 hours of bird video was captured overlooking Sequim Bay over a series of weeks. An additional 2 hours of video of birds was also captured during two weeks overlooking Dungeness Bay within the Strait of Juan de Fuca. Bats and passerine birds (swallows) were also recorded at dusk on the MSL campus during nine evenings. An observer noted the identity of objects viewed through the camera concurrently with recording. These video files will provide the information necessary to produce and test software developed during FY2013. The annotation will also form the basis for creation of a method to reliably identify recorded objects.

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

NARCIS (Netherlands)

Buchin, K.; Sijben, S.; van Loon, E.E.; Sapir, N.; Mercier, S.; Arseneau, T.J.M.; Willems, E.P.

2015-01-01

Background: 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

Effects of wind turbines on upland nesting birds in Conservation Reserve Program grasslands

Science.gov (United States)

Leddy, K.L.; Higgins, K.F.; Naugle, D.E.

1999-01-01

Grassland passerines were surveyed during summer 1995 on the Buffalo Ridge Wind Resource Area in southwestern Minnesota to determine the relative influence of wind turbines on overall densities of upland nesting birds in Conservation Reserve Program (CRP) grasslands. Birds were surveyed along 40 m fixed width transects that were placed along wind turbine strings within three CRP fields and in three CRP fields without turbines. Conservation Reserve Program grasslands without turbines and areas located 180 m from turbines supported higher densities (261.0-312.5 males/100 ha) of grassland birds than areas within 80 m of turbines (58.2-128.0 males/100 ha). Human disturbance, turbine noise, and physical movements of turbines during operation may have disturbed nesting birds. We recommend that wind turbines be placed within cropland habitats that support lower densities of grassland passerines than those found in CRP grasslands.

Habitat selection and post-release movement of reintroduced brown treecreeper individuals in restored temperate woodland.

Directory of Open Access Journals (Sweden)

Victoria A Bennett

Full Text Available It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual's dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals of the brown treecreeper (Climacteris picumnus into two nature reserves in south-eastern Australia. We radio-tracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual's gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species' requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides, which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals

The Bird.

Science.gov (United States)

Hannon, Jean

2001-01-01

Students use a dead bird to learn about bird life, anatomy, and death. Students examine a bird body and discuss what happened to the bird. Uses outdoor education as a resource for learning about animals. (SAH)

Tracking the movement of Hawaiian volcanoes; Global Positioning System (GPS) measurement

Science.gov (United States)

Dvorak, J.J.

1992-01-01

Most, if not all, volcanic eruptions are preceded by surface movements near the volcano. These ground movements are the response of the shallow crust to the accumulation of the magma or the buildup of magma pressure within a subterranean reservoir beneath the volcano. As the magma reservoir expands, the summit and the flanks of the volcano rise and spread apart. Measurements made at many volcanoes show that slow ground movement may precede an eruption by as many as several years. Sudden increases in the rate of ground movement often precede an eruption by a few hours or days.

Summary of intrinsic and extrinsic factors affecting detection probability of marsh birds

Science.gov (United States)

Conway, C.J.; Gibbs, J.P.

2011-01-01

Many species of marsh birds (rails, bitterns, grebes, etc.) rely exclusively on emergent marsh vegetation for all phases of their life cycle, and many organizations have become concerned about the status and persistence of this group of birds. Yet, marsh birds are notoriously difficult to monitor due to their secretive habits. We synthesized the published and unpublished literature and summarized the factors that influence detection probability of secretive marsh birds in North America. Marsh birds are more likely to respond to conspecific than heterospecific calls, and seasonal peak in vocalization probability varies among co-existing species. The effectiveness of morning versus evening surveys varies among species and locations. Vocalization probability appears to be positively correlated with density in breeding Virginia Rails (Rallus limicola), Soras (Porzana carolina), and Clapper Rails (Rallus longirostris). Movement of birds toward the broadcast source creates biases when using count data from callbroadcast surveys to estimate population density. Ambient temperature, wind speed, cloud cover, and moon phase affected detection probability in some, but not all, studies. Better estimates of detection probability are needed. We provide recommendations that would help improve future marsh bird survey efforts and a list of 14 priority information and research needs that represent gaps in our current knowledge where future resources are best directed. ?? Society of Wetland Scientists 2011.

A Heritage Tourism and Tourist Flow Pattern: A Perspective on Traditional versus Modern Technologies in Tracking the Tourists

Directory of Open Access Journals (Sweden)

Mohamad Akmal Mohamad Toha

2015-05-01

Full Text Available Historic city offers tourists a mixture of cultural heritage and leisure activities in a unique set-ting. However, there are limited research addressing the movement and behavior of tourists in tourism destination that leads the understanding of urban function towards "heterogeneity" and "multi functionality". In order to maintain and ensuring long-term success as an attractive des-tination for tourists, tourist’s movement and behavior is most likely an important element to be fully understood by decision maker. Hence, the method of tracking tourist is one of the im-portant aspects in providing better picture, especially in the context of obtaining accurate data on the tourist’s movement. Hence, the studies were designed to determine the potential worth of the various tracking technologies for research on tourist movement in Melaka historic cities. The discussion in this paper focusing on 6 traditional and 5 modern methods of tracking tourists movement. Accuracy, availability, location of the study area, costs, privacy of travelling, dura-tion of tracking and suitability in tracking daily movement are used as variables to identify which tracking method is the best to track tourists in heritage site. Existing literature indicates that application of GPS in a smart phone emerges as the best option method for tracking tour-ists in Melaka heritage site. By comparing methods of tracking tourists, it may assist researcher to choose the best option of method to obtain accurate and precise data about tourist move-ment. Thus, the study offered a systematic review of several tracking technologies in which potentially able to push the boundaries of tourism studies, as well as improving policy making, planning and management in tourism area.

Modeling the flocking propensity of passerine birds in two Neotropical habitats.

Science.gov (United States)

Pomara, Lars Y; Cooper, Robert J; Petit, Lisa J

2007-08-01

We examined the importance of mixed-species flock abundance, individual bird home range size, foraging height, and foraging patch characteristics in predicting the propensity for five Neotropical passerine bird species (Slaty Antwren, Myrmotherula schisticolor; Golden-crowned Warbler, Basileuterus culicivorus; Slate-throated Redstart, Myioborus miniatus; Wilson's Warbler, Wilsonia pusilla; and Black-and-white Warbler, Mniotilta varia) to forage within flocks, rather than solitarily. We used study plots in primary mid-elevation forest and in shade coffee fields in western Panama. We expected that all species would spend as much time as possible flocking, but that the social and environmental factors listed above would limit compatibility between flock movements and individual bird movements, explaining variability in flocking propensity both within and among species. Flocking propensity was well predicted by home range size and flock abundance together, for four of the five species. While flock abundance was uniform across plots, home range sizes varied among species and plots, so that home range size appeared to be the principle factor limiting flocking propensity. Estimates of flock abundance were still required, however, for calculating flocking propensity values. Foraging height and patch characteristics slightly improved predictive ability for the remaining species, M. miniatus. In general, individual birds tended to join flocks whenever one was available inside their home range, regardless of a flock's specific location within the home range. Flocking propensities of individual species were lower in shade coffee fields than in forests, and probably vary across landscapes with variations in habitat. This variability affects the stability and species composition of flocks, and may affect survival rates of individual species.

P1-20: The Relation of Eye and Hand Movement during Multimodal Recall Memory

Directory of Open Access Journals (Sweden)

Eun-Sol Kim

2012-10-01

Full Text Available Eye and hand movement tracking has been proven to be a successful tool and is widely used to figure out characteristics of human cognition in language or visual processing (Just & Carpenter, 1976 Cognitive Psychology 8441–480. Eye movement has proven to be a successful measure to figure out characteristics of human language and visual processing (Rayner, 1998 Psychological Bulletin 124(3 372–422. Recently, mouse tracking was used for social-cognition-like categorization of sex-atypical faces and studying spoken-language processes (Magnuson, 2005 PNAS 102(28 9995–9996; Spivey et al., 2005 PNAS 102 10393–10398. Here, we present a framework that uses both eye gaze and hand movement simultaneously for analyzing the relation of them during memory retrieval. We tracked eye and mouse movements when the subject was watching a drama and playing a multimodal memory game (MMG, a cognitive task designed to investigate the recall memory mechanisms in watching video dramas (Zhang, 2009 AAAI 2009 Spring Symposium: Agents that Learn from Human Teachers 144–149. Experimental results show that eye tracking and mouse tracking provide complementary information about underlying cognitive processes. Also, we found some interesting patterns in eye-hand movement during multimodal memory recall.

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

Science.gov (United States)

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

Capturing Hotspots For Constrained Indoor Movement

DEFF Research Database (Denmark)

Ahmed, Tanvir; Pedersen, Torben Bach; Lu, Hua

2013-01-01

Finding the hotspots in large indoor spaces is very important for getting overloaded locations, security, crowd management, indoor navigation and guidance. The tracking data coming from indoor tracking are huge in volume and not readily available for finding hotspots. This paper presents a graph......-based model for constrained indoor movement that can map the tracking records into mapping records which represent the entry and exit times of an object in a particular location. Then it discusses the hotspots extraction technique from the mapping records....

Precise Head Tracking in Hearing Applications

Science.gov (United States)

Helle, A. M.; Pilinski, J.; Luhmann, T.

2015-05-01

The paper gives an overview about two research projects, both dealing with optical head tracking in hearing applications. As part of the project "Development of a real-time low-cost tracking system for medical and audiological problems (ELCoT)" a cost-effective single camera 3D tracking system has been developed which enables the detection of arm and head movements of human patients. Amongst others, the measuring system is designed for a new hearing test (based on the "Mainzer Kindertisch"), which analyzes the directional hearing capabilities of children in cooperation with the research project ERKI (Evaluation of acoustic sound source localization for children). As part of the research project framework "Hearing in everyday life (HALLO)" a stereo tracking system is being used for analyzing the head movement of human patients during complex acoustic events. Together with the consideration of biosignals like skin conductance the speech comprehension and listening effort of persons with reduced hearing ability, especially in situations with background noise, is evaluated. For both projects the system design, accuracy aspects and results of practical tests are discussed.

Modeling Habitat Suitability of Migratory Birds from Remote Sensing Images Using Convolutional Neural Networks

Science.gov (United States)

Su, Jin-He; Piao, Ying-Chao; Luo, Ze; Yan, Bao-Ping

2018-01-01

Simple Summary The understanding of the spatio-temporal distribution of the species habitats would facilitate wildlife resource management and conservation efforts. Existing methods have poor performance due to the limited availability of training samples. More recently, location-aware sensors have been widely used to track animal movements. The aim of the study was to generate suitability maps of bar-head geese using movement data coupled with environmental parameters, such as remote sensing images and temperature data. Therefore, we modified a deep convolutional neural network for the multi-scale inputs. The results indicate that the proposed method can identify the areas with the dense goose species around Qinghai Lake. In addition, this approach might also be interesting for implementation in other species with different niche factors or in areas where biological survey data are scarce. Abstract With the application of various data acquisition devices, a large number of animal movement data can be used to label presence data in remote sensing images and predict species distribution. In this paper, a two-stage classification approach for combining movement data and moderate-resolution remote sensing images was proposed. First, we introduced a new density-based clustering method to identify stopovers from migratory birds’ movement data and generated classification samples based on the clustering result. We split the remote sensing images into 16 × 16 patches and labeled them as positive samples if they have overlap with stopovers. Second, a multi-convolution neural network model is proposed for extracting the features from temperature data and remote sensing images, respectively. Then a Support Vector Machines (SVM) model was used to combine the features together and predict classification results eventually. The experimental analysis was carried out on public Landsat 5 TM images and a GPS dataset was collected on 29 birds over three years. The results

Assessing the risk of highly pathogenic avian influenza H5N1 transmission through poultry movements in Bali, Indonesia.

Science.gov (United States)

Roche, Sharon E; Cogger, Naomi; Garner, M Graeme; Putra, Anak Agung Gde; Toribio, Jenny-Ann L M L

2014-03-01

Indonesia continues to report the highest number of human and poultry cases of highly pathogenic avian influenza H5N1. The disease is considered to be endemic on the island of Bali. Live bird markets are integral in the poultry supply chain on Bali and are important, nutritionally and culturally, for the rural and urban human populations. Due to the lack of biosecurity practiced along the supply chain from producer to live bird markets, there is a need to understand the risks associated with the spread of H5N1 through live bird movements for effective control. Resources to control H5N1 in Indonesia are very limited and cost effective strategies are needed. We assessed the probability a live bird market is infected through live poultry movements and assessed the effects of implementing two simple and low cost control measures on this risk. Results suggest there is a high risk a live bird market is infected (0.78), and risk mitigation strategies such as detecting and removing infected poultry from markets reduce this risk somewhat (range 0.67-0.76). The study demonstrates the key role live poultry movements play in transmitting H5N1 and the need to implement a variety of control measures to reduce disease spread. Copyright © 2014 Elsevier B.V. All rights reserved.

Adaptive timing of detachment in a tick parasitizing hole-nesting birds.

Science.gov (United States)

White, J; Heylen, D J A; Matthysen, E

2012-02-01

In non-permanent parasites with low intrinsic mobility such as ticks, dispersal is highly dependent on host movements as well as the timing of separation from the hosts. Optimal detachment behaviour is all the more crucial in nidicolous ticks as the risk of detaching in non-suitable habitat is high. In this study, we experimentally investigated the detachment behaviour of Ixodes arboricola, a nidicolous tick that primarily infests birds roosting in tree-holes. We infested great tits with I. arboricola larvae or nymphs, and submitted the birds to 2 experimental treatments, a control treatment in which birds had normal access to nest boxes and an experimental treatment, in which the birds were prevented access to their nest boxes for varying lengths of time. In the control group, most ticks detached within 5 days, whereas in the experimental group, ticks remained on the bird for as long as the bird was prevented access (up to 14 days). This prolonged attachment caused a decrease in survival and engorgement weight in nymphs, but not in larvae. The capacity of I. arboricola larvae to extend the duration of attachment in non-suitable environments with no apparent costs, may be an adaptation to unpredictable use of cavities by roosting hosts during winter, and at the same time may facilitate dispersal of the larval instars.

30 CFR 56.9102 - Movement of independently operating rail equipment.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Movement of independently operating rail... MINES Loading, Hauling, and Dumping Traffic Safety § 56.9102 Movement of independently operating rail equipment. Movement of two or more pieces of rail equipment operating independently on the same track shall...

Model-Based Motion Tracking of Infants

DEFF Research Database (Denmark)

Olsen, Mikkel Damgaard; Herskind, Anna; Nielsen, Jens Bo

2014-01-01

Even though motion tracking is a widely used technique to analyze and measure human movements, only a few studies focus on motion tracking of infants. In recent years, a number of studies have emerged focusing on analyzing the motion pattern of infants, using computer vision. Most of these studies...... are based on 2D images, but few are based on 3D information. In this paper, we present a model-based approach for tracking infants in 3D. The study extends a novel study on graph-based motion tracking of infants and we show that the extension improves the tracking results. A 3D model is constructed...

Social network analysis of the movement of poultry to and from live bird markets in Bali and Lombok, Indonesia.

Science.gov (United States)

Kurscheid, J; Stevenson, M; Durr, P A; Toribio, J-A L M L; Kurscheid, S; Ambarawati, I G A A; Abdurrahman, M; Fenwick, S

2017-12-01

Highly pathogenic avian influenza H5N1 has resulted in large losses to the Indonesian poultry sector. Evidence suggests that live bird markets (LBMs) play an important role in the epidemiology of the disease. Knowledge of the frequency and type of contact between the various poultry market players should allow animal health authorities to develop a better understanding of factors influencing virus transmission between Indonesian villages. A questionnaire-based cross-sectional survey was conducted in 17 LBMs on the neighbouring Indonesian islands of Bali and Lombok to investigate the movement patterns of poultry to and from markets. Using social network analyses, a network of contacts was created for each island from a total of 413 live poultry traders and 134 customers. Individual nodes with high degree and/or betweenness were identified in each network. The Lombok network was more dense and connected than the Bali network indicating that disease transmission would be more efficient in the Lombok network. Our findings indicate that whilst live poultry are typically transported over relatively short distances of approximately 10 km, it is not uncommon for traders and customers to travel in excess of 100 km to buy or sell poultry, which may facilitate the spread of disease over a large geographical area. This study highlights the different roles markets play in poultry movement networks and their potential for disease dissemination. The identification of highly influential market nodes allows authorities to target HPAI surveillance activities to locations where disease is more likely to be present, which is crucial in low-resource settings. © 2017 Blackwell Verlag GmbH.

Coastal Resources Atlas: Long Island: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, and gulls and...

Bird-like anatomy, posture, and behavior revealed by an early jurassic theropod dinosaur resting trace

Science.gov (United States)

Milner, Andrew R.C.; Harris, J.D.; Lockley, M.G.; Kirkland, J.I.; Matthews, N.A.

2009-01-01

Background: Fossil tracks made by non-avian theropod dinosaurs commonly reflect the habitual bipedal stance retained in living birds. Only rarely-captured behaviors, such as crouching, might create impressions made by the hands. Such tracks provide valuable information concerning the often poorly understood functional morphology of the early theropod forelimb. Methodology/Principal Findings: Here we describe a well-preserved theropod trackway in a Lower Jurassic (???198 millionyear- old) lacustrine beach sandstone in the Whitmore Point Member of the Moenave Formation in southwestern Utah. The trackway consists of prints of typical morphology, intermittent tail drags and, unusually, traces made by the animal resting on the substrate in a posture very similar to modern birds. The resting trace includes symmetrical pes impressions and well-defined impressions made by both hands, the tail, and the ischial callosity. Conclusions/Significance: The manus impressions corroborate that early theropods, like later birds, held their palms facing medially, in contrast to manus prints previously attributed to theropods that have forward-pointing digits. Both the symmetrical resting posture and the medially-facing palms therefore evolved by the Early Jurassic, much earlier in the theropod lineage than previously recognized, and may characterize all theropods.

Bird-like anatomy, posture, and behavior revealed by an early jurassic theropod dinosaur resting trace.

Science.gov (United States)

Milner, Andrew R C; Harris, Jerald D; Lockley, Martin G; Kirkland, James I; Matthews, Neffra A

2009-01-01

Fossil tracks made by non-avian theropod dinosaurs commonly reflect the habitual bipedal stance retained in living birds. Only rarely-captured behaviors, such as crouching, might create impressions made by the hands. Such tracks provide valuable information concerning the often poorly understood functional morphology of the early theropod forelimb. Here we describe a well-preserved theropod trackway in a Lower Jurassic ( approximately 198 million-year-old) lacustrine beach sandstone in the Whitmore Point Member of the Moenave Formation in southwestern Utah. The trackway consists of prints of typical morphology, intermittent tail drags and, unusually, traces made by the animal resting on the substrate in a posture very similar to modern birds. The resting trace includes symmetrical pes impressions and well-defined impressions made by both hands, the tail, and the ischial callosity. The manus impressions corroborate that early theropods, like later birds, held their palms facing medially, in contrast to manus prints previously attributed to theropods that have forward-pointing digits. Both the symmetrical resting posture and the medially-facing palms therefore evolved by the Early Jurassic, much earlier in the theropod lineage than previously recognized, and may characterize all theropods.

Visual and radar observations of birds in relation to collision risk at the Horns Rev offshore wind farm. Annual status report 2003

Energy Technology Data Exchange (ETDEWEB)

Kjaer Christensen, T.; Hounisen, J.P.; Clausager, I.; Krag Petersen, I.

2004-07-01

The aim of the project is to assess the collision risk between birds and wind turbines at the Horns Rev wind farm. In 2003 the studies focused on describing bird movements in relation to the wind farm and to identify the species-specific behavioural responses towards the wind turbines shown by migrating and staging species. The Horns Rev area lies in a region known to be important for substantial water bird migration as well as holding internationally important numbers of several wintering and staging water bird species. (au)

Avian Influenza H5N1 and the Wild Bird Trade in Hanoi, Vietnam

Directory of Open Access Journals (Sweden)

F. Brooks-Moizer

2009-06-01

Full Text Available Wildlife trade and emerging infectious diseases pose significant threats to human and animal health and global biodiversity. Legal and illegal trade in domestic and wild birds has played a significant role in the global spread of highly pathogenic avian influenza H5N1, which has killed more than 240 people, many millions of poultry, and an unknown number of wild birds and mammals, including endangered species, since 2003. This 2007 study provides evidence for a significant decline in the scale of the wild bird trade in Hanoi since previous surveys in 2000 (39.7% decline and 2003 (74.1% decline. We attribute this to the enforcement of Vietnam's Law 169/2005/QD UBND, introduced in 2005, which prohibits the movement and sale of wild and ornamental birds in cities. Nevertheless, 91.3% (21/23 of bird vendors perceived no risk of H5N1 infection from their birds, and the trade continues, albeit at reduced levels, in open market shops. These findings highlight the importance of continued law enforcement to maintain this trade reduction and the associated benefits to human and animal health and biodiversity conservation.

Can antibodies against flies alter malaria transmission in birds by changing vector behavior?

Science.gov (United States)

Ghosh, Suma; Waite, Jessica L; Clayton, Dale H; Adler, Frederick R

2014-10-07

Transmission of insect-borne diseases is shaped by the interactions among parasites, vectors, and hosts. Any factor that alters movement of infected vectors from infected to uninfeced hosts will in turn alter pathogen spread. In this paper, we study one such pathogen-vector-host system, avian malaria in pigeons transmitted by fly ectoparasites, where both two-way and three-way interactions play a key role in shaping disease spread. Bird immune defenses against flies can decrease malaria prevalence by reducing fly residence time on infected birds or increase disease prevalence by enhancing fly movement and thus infection transmission. We develop a mathematical model that illustrates how these changes in vector behavior influence pathogen transmission and show that malaria prevalence is maximized at an intermediate level of defense avoidance by the flies. Understanding how host immune defenses indirectly alter disease transmission by influencing vector behavior has implications for reducing the transmission of human malaria and other vectored pathogens. Published by Elsevier Ltd.

ATPase Cycle of the Nonmotile Kinesin NOD Allows Microtubule End Tracking and Drives Chromosome Movement

Energy Technology Data Exchange (ETDEWEB)

Cochran, J.; Sindelar, C; Mulko, N; Collins, K; Kong, S; Hawley, R; Kull, F

2009-01-01

Segregation of nonexchange chromosomes during Drosophila melanogaster meiosis requires the proper function of NOD, a nonmotile kinesin-10. We have determined the X-ray crystal structure of the NOD catalytic domain in the ADP- and AMPPNP-bound states. These structures reveal an alternate conformation of the microtubule binding region as well as a nucleotide-sensitive relay of hydrogen bonds at the active site. Additionally, a cryo-electron microscopy reconstruction of the nucleotide-free microtubule-NOD complex shows an atypical binding orientation. Thermodynamic studies show that NOD binds tightly to microtubules in the nucleotide-free state, yet other nucleotide states, including AMPPNP, are weakened. Our pre-steady-state kinetic analysis demonstrates that NOD interaction with microtubules occurs slowly with weak activation of ADP product release. Upon rapid substrate binding, NOD detaches from the microtubule prior to the rate-limiting step of ATP hydrolysis, which is also atypical for a kinesin. We propose a model for NOD's microtubule plus-end tracking that drives chromosome movement.

Towards an IMU Evaluation Framework for Human Body Tracking.

Science.gov (United States)

Venek, Verena; Kremser, Wolfgang; Schneider, Cornelia

2018-01-01

Existing full-body tracking systems, which use Inertial Measurement Units (IMUs) as sensing unit, require expert knowledge for setup and data collection. Thus, the daily application for human body tracking is difficult. In particular, in the field of active and assisted living (AAL), tracking human movements would enable novel insights not only into the quantity but also into the quality of human movement, for example by monitoring functional training. While the current market offers a wide range of products with vastly different properties, literature lacks guidelines for choosing IMUs for body tracking applications. Therefore, this paper introduces developments towards an IMU evaluation framework for human body tracking which compares IMUs against five requirement areas that consider device features and data quality. The data quality is assessed by conducting a static and a dynamic error analysis. In a first application to four IMUs of different component consumption, the IMU evaluation framework convinced as promising tool for IMU selection.

Post-release survival and movements patterns of roosterfish (Nematistius pectoralis off the Central American coastline

Directory of Open Access Journals (Sweden)

Chugey A Sepulveda

2015-03-01

Full Text Available Acoustic telemetry was used to assess immediate post-release survival and track the short-term movement patterns of roosterfish Nematistius pectoralis between 2008 and 2010. Seven roosterfish (85 to 146 cm fork length, FL were continuously tracked along the Central American coastline for periods of up to 28 h following capture on recreational fishing tackle. All seven roosterfish were initially captured and spent the duration of the track period proximal to the coastline in waters <100 m of depth. From depth records and horizontal movements, it was determined that all seven roosterfish survived the acute effects of capture. The greatest depth achieved by any of the tracked individuals was 62 m and collectively roosterfish spent over 90% of the track records between the surface and 12 m. For all tracks, fish size showed no effect on maximum or average dive depth and the average day (7 ± 2 m and night (6 ± 2 m depths were similar among individuals. Mean water temperature for all tracks was 28 ± 1°C, with the lowest temperature experienced at depth being 23°C. Total horizontal movements from the roosterfish in this study ranged from 14.7 to 42.2 km and averaged 1.5 ± 0.4 km h-1. Data on movements in relation to bathymetry, prey presence and habitat structure are discussed. Collectively, these data provide insight into the immediate post-release disposition and short-term movements of this poorly studied species along the coast of Central America.

The effect of wind turbines on the bird population at Blyth Harbour

International Nuclear Information System (INIS)

Still, D.; Little, B.; Lawrence, S.

1996-01-01

Bird monitoring was carried out at Blyth Harbour Wind Farm which consists of a line of nine 300kW wind turbines distributed at 200m intervals along a 1.2km breakwater. The harbour breakwater is designated as part of a Site of Special Scientific Interest as it supports an internationally important winter population of Purple Sandpipers. The Blyth estuary is to be designated as part of a Special Protection Area under the EC Habitats Directive and as part of a proposed RAMSAR site due to its peak periods up to c.5000 bird movements/day occur adjacent to the windfarm. Mortality surveys (at one week intervals) were carried out on adjacent beaches to the wind farm in order to assess the background numbers of bird corpses and locate wind farm casualties. Supplementary mortality searches were carried out near power lines less than 2.5 km upstream from the wind farm. Tests of the efficiency of the mortality surveys have been carried out in order to assess the likely impact on the local bird populations. In spite of the large bird population supported by the harbour and its close proximity to the wind farm there have been relatively few collision victims (31) since the windfarm was commissioned. This is equivalent to less than 1.34 bird strike/wind turbine per annum. (author)

Extending Track Analysis from Animals in the Lab to Moving Objects Anywhere

NARCIS (Netherlands)

Dommelen, W. van; Laar, P.J.L.J. van de; Noldus, L.P.J.J.

2013-01-01

In this chapter we compare two application domains in which the tracking of objects and the analysis of their movements are core activities, viz. animal tracking and vessel tracking. More specifically, we investigate whether EthoVision XT, a research tool for video tracking and analysis of the

Effects of reward on the accuracy and dynamics of smooth pursuit eye movements.

Science.gov (United States)

Brielmann, Aenne A; Spering, Miriam

2015-08-01

Reward modulates behavioral choices and biases goal-oriented behavior, such as eye or hand movements, toward locations or stimuli associated with higher rewards. We investigated reward effects on the accuracy and timing of smooth pursuit eye movements in 4 experiments. Eye movements were recorded in participants tracking a moving visual target on a computer monitor. Before target motion onset, a monetary reward cue indicated whether participants could earn money by tracking accurately, or whether the trial was unrewarded (Experiments 1 and 2, n = 11 each). Reward significantly improved eye-movement accuracy across different levels of task difficulty. Improvements were seen even in the earliest phase of the eye movement, within 70 ms of tracking onset, indicating that reward impacts visual-motor processing at an early level. We obtained similar findings when reward was not precued but explicitly associated with the pursuit target (Experiment 3, n = 16); critically, these results were not driven by stimulus prevalence or other factors such as preparation or motivation. Numerical cues (Experiment 4, n = 9) were not effective. (c) 2015 APA, all rights reserved).

SmoothMoves : Smooth pursuits head movements for augmented reality

NARCIS (Netherlands)

Esteves, Augusto; Verweij, David; Suraiya, Liza; Islam, Rasel; Lee, Youryang; Oakley, Ian

2017-01-01

SmoothMoves is an interaction technique for augmented reality (AR) based on smooth pursuits head movements. It works by computing correlations between the movements of on-screen targets and the user's head while tracking those targets. The paper presents three studies. The first suggests that head

Tracking Europe: Mobility, Diaspora, and the Politics of Location

NARCIS (Netherlands)

Verstraete, G.E.E.

2010-01-01

Tracking Europe is a bold interdisciplinary critique of claims regarding the free movement of goods, people, services, and capital throughout Europe. Ginette Verstraete interrogates European discourses on unlimited movement for everyone and a utopian unity-in-diversity in light of contemporary

On Biometrics With Eye Movements.

Science.gov (United States)

Zhang, Youming; Juhola, Martti

2017-09-01

Eye movements are a relatively novel data source for biometric identification. When video cameras applied to eye tracking become smaller and more efficient, this data source could offer interesting opportunities for the development of eye movement biometrics. In this paper, we study primarily biometric identification as seen as a classification task of multiple classes, and secondarily biometric verification considered as binary classification. Our research is based on the saccadic eye movement signal measurements from 109 young subjects. In order to test the data measured, we use a procedure of biometric identification according to the one-versus-one (subject) principle. In a development from our previous research, which also involved biometric verification based on saccadic eye movements, we now apply another eye movement tracker device with a higher sampling frequency of 250 Hz. The results obtained are good, with correct identification rates at 80-90% at their best.

An Indoor Tracking System Based on Bluetooth Technology

OpenAIRE

Opoku, Samuel King

2012-01-01

Implementations of tracking systems have become prevalent issues in modern technology due to its advantage of location detection of objects. Objects are usually tracked using trackers based on GPS, GSM, RFID and Bluetooth signal strength implementation. These mechanisms usually require line of sight operations, limited coverage and low level programming language for accessing Bluetooth signal strength. This paper presents an alternative technique for tracking the movement of indoor objects ba...

Binocular eye movement control and motion perception: What is being tracked?

NARCIS (Netherlands)

J. van der Steen (Hans); J. Dits (Joyce)

2012-01-01

textabstractPURPOSE. We investigated under what conditions humans can make independent slow phase eye movements. The ability to make independent movements of the two eyes generally is attributed to few specialized lateral eyed animal species, for example chameleons. In our study, we showed that

Effects of wrist tendon vibration on arm tracking in people poststroke.

Science.gov (United States)

Conrad, Megan O; Scheidt, Robert A; Schmit, Brian D

2011-09-01

The goal of this study was to evaluate the influence of wrist tendon vibration on a multijoint elbow/shoulder tracking task. We hypothesized that tendon vibration applied at the wrist musculature would improve upper arm tracking performance in chronic stroke survivors through increased, Ia-afferent feedback to the central nervous system (CNS). To test this hypothesis, 10 chronic stroke and 5 neurologically intact subjects grasped the handle of a planar robot as they tracked a target through a horizontal figure-8 pattern. A total of 36 trials were completed by each subject. During the middle trials, 70-Hz tendon vibration was applied at the wrist flexor tendons. Position, velocity, and electromyography data were evaluated to compare the quality of arm movements before, during, and after trials with concurrent vibration. Despite tracking a target that moved at a constant velocity, hand trajectories appeared to be segmented, displaying alternating intervals of acceleration and deceleration. Segments were identifiable in tangential velocity data as single-peaked, bell-shaped speed pulses. When tendon vibration was applied at the wrist musculature, stroke subjects experienced improved tracking performance in that hand path lengths and peak speed variability decreased, whereas movement smoothness increased. These performance improvements were accompanied by decreases in the muscle activity during movement. Possible mechanisms behind improved movement control in response to tendon vibration may include improved sensorimotor integration or improved cortical modulation of spinal reflex activity.

The effect of feeding time on dispersal of Virola seeds by toucans determined from GPS tracking and accelerometers

NARCIS (Netherlands)

Kays, Roland; Jansen, Patrick A.; Knecht, Elise M. H.; Vohwinkel, Reinhard; Wikelski, Martin

2011-01-01

Seed dispersal is critical to understanding forest dynamics but is hard to study because tracking seeds is difficult. Even for the best-studied dispersal system of the Neotropics, Virola nobilis, the dispersal kernel remains unknown. We combined high-resolution GPS/3D-acceleration bird tracking,

Principal direction of inertia for 3D trajectories from patient-specific TMJ movement.

Science.gov (United States)

Kim, Dae-Seung; Choi, Soon-Chul; Lee, Sam-Sun; Heo, Min-Suk; Huh, Kyung-Hoe; Hwang, Soon-Jung; Kim, Seong-Ha; Yi, Won-Jin

2013-03-01

Accurate simulation and evaluation of mandibular movement is fundamental for the analysis of functional changes and effects of the mandible and maxilla before and after surgical treatments. We applied principal axes of inertia to the three-dimensional (3D) trajectories generated by patient-specific simulations of TMJ movements for the functional evaluations of mandible movement. Three-dimensional movements of the mandible and the maxilla were tracked based on a patient-specific splint and an optical tracking system. The dental occlusion recorded on the sprint provided synchronization for initial movement in the tracking and the simulation phases. The translation and rotation recorded during movement tracking was applied sequentially to the mandibular model in relation to a fixed maxilla model. The sequential 3D positions of selected landmarks on the mandible were calculated based on the reference coordinate system. The landmarks selected for analysis were bilateral condyles and pogonion points. The moment of inertia tensor was calculated with respect to the 3D trajectory points. Using the unit vectors along the principal axes derived from the tensor matrix, α, β and γ rotations around z-, y- and x-axes were determined to represent the principal directions as principal rotations respectively. The γ direction showed the higher standard deviation, variation of directions, than other directions at all the landmarks. The mandible movement has larger kinematic redundancy in the γ direction than α and β during mouth opening and closing. Principal directions of inertia would be applied to analyzing the changes in angular motion of trajectories introduced by mandibular shape changes from surgical treatments and also to the analysis of the influence of skeletal deformities on mandibular movement asymmetry. Copyright © 2012 Elsevier Ltd. All rights reserved.

Eye and head movements shape gaze shifts in Indian peafowl.

Science.gov (United States)

Yorzinski, Jessica L; Patricelli, Gail L; Platt, Michael L; Land, Michael F

2015-12-01

Animals selectively direct their visual attention toward relevant aspects of their environments. They can shift their attention using a combination of eye, head and body movements. While we have a growing understanding of eye and head movements in mammals, we know little about these processes in birds. We therefore measured the eye and head movements of freely behaving Indian peafowl (Pavo cristatus) using a telemetric eye-tracker. Both eye and head movements contributed to gaze changes in peafowl. When gaze shifts were smaller, eye movements played a larger role than when gaze shifts were larger. The duration and velocity of eye and head movements were positively related to the size of the eye and head movements, respectively. In addition, the coordination of eye and head movements in peafowl differed from that in mammals; peafowl exhibited a near-absence of the vestibulo-ocular reflex, which may partly result from the peafowl's ability to move their heads as quickly as their eyes. © 2015. Published by The Company of Biologists Ltd.

Bird-like anatomy, posture, and behavior revealed by an early jurassic theropod dinosaur resting trace.

Directory of Open Access Journals (Sweden)

Andrew R C Milner

Full Text Available BACKGROUND: Fossil tracks made by non-avian theropod dinosaurs commonly reflect the habitual bipedal stance retained in living birds. Only rarely-captured behaviors, such as crouching, might create impressions made by the hands. Such tracks provide valuable information concerning the often poorly understood functional morphology of the early theropod forelimb. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a well-preserved theropod trackway in a Lower Jurassic ( approximately 198 million-year-old lacustrine beach sandstone in the Whitmore Point Member of the Moenave Formation in southwestern Utah. The trackway consists of prints of typical morphology, intermittent tail drags and, unusually, traces made by the animal resting on the substrate in a posture very similar to modern birds. The resting trace includes symmetrical pes impressions and well-defined impressions made by both hands, the tail, and the ischial callosity. CONCLUSIONS/SIGNIFICANCE: The manus impressions corroborate that early theropods, like later birds, held their palms facing medially, in contrast to manus prints previously attributed to theropods that have forward-pointing digits. Both the symmetrical resting posture and the medially-facing palms therefore evolved by the Early Jurassic, much earlier in the theropod lineage than previously recognized, and may characterize all theropods.

Bird Survey in Storruns windfarm in Jaemtland; Faagelundersoekning vid Storruns vindkraftanlaeggning Jaemtland

Energy Technology Data Exchange (ETDEWEB)

Falkdalen, Ulla; Falkdalen Lindahl, Lars; Nygaard, Torgeir

2013-08-15

A survey of the bird populations in Oldfjaellen in Jaemtland county, Sweden, was initiated in 2003 prior to the construction of a wind-farm on two adjacent hills, Storrun and Froesoerun by the lake Oevre Oldsjoen. After a gap in the surveys in 2004, comprehensive studies were continued during 2005 - 2008, prior to the construction. The construction-work started during autumn 2008, and the turbines were erected during 2009. Power production was started during the autumn of 2009. The post-construction bird studies were carried out in 2010 and 2011. This report summarizes all the studies that were performed before and after the construction of the wind-farm. Many of the separate studies were made using a BACI method (Before-After-Control-Impact) enabling comparisons of the situation before and after development, using a control area. In addition, a study of collision rates and scavenger removal rates is reported. As expected, the movement and migration of birds over Storrun was of rather limited magnitude. Although the majority of observations during the investigated periods spring and autumn are assumed to be migrating birds, larger flocks of birds are rare in the area. Ca. 20 % of all the birds that passed through or near the wind-farm area flew in heights comparable to the rotor-swept zone. However, more than 40 % of the raptors and waders passed through in that zone, which implies a collision risk. These two groups of birds have shown to be particularly prone to collisions with rotor blades in other studies.

Accurately tracking single-cell movement trajectories in microfluidic cell sorting devices.

Science.gov (United States)

Jeong, Jenny; Frohberg, Nicholas J; Zhou, Enlu; Sulchek, Todd; Qiu, Peng

2018-01-01

Microfluidics are routinely used to study cellular properties, including the efficient quantification of single-cell biomechanics and label-free cell sorting based on the biomechanical properties, such as elasticity, viscosity, stiffness, and adhesion. Both quantification and sorting applications require optimal design of the microfluidic devices and mathematical modeling of the interactions between cells, fluid, and the channel of the device. As a first step toward building such a mathematical model, we collected video recordings of cells moving through a ridged microfluidic channel designed to compress and redirect cells according to cell biomechanics. We developed an efficient algorithm that automatically and accurately tracked the cell trajectories in the recordings. We tested the algorithm on recordings of cells with different stiffness, and showed the correlation between cell stiffness and the tracked trajectories. Moreover, the tracking algorithm successfully picked up subtle differences of cell motion when passing through consecutive ridges. The algorithm for accurately tracking cell trajectories paves the way for future efforts of modeling the flow, forces, and dynamics of cell properties in microfluidics applications.

Accurately tracking single-cell movement trajectories in microfluidic cell sorting devices.

Directory of Open Access Journals (Sweden)

Jenny Jeong

Full Text Available Microfluidics are routinely used to study cellular properties, including the efficient quantification of single-cell biomechanics and label-free cell sorting based on the biomechanical properties, such as elasticity, viscosity, stiffness, and adhesion. Both quantification and sorting applications require optimal design of the microfluidic devices and mathematical modeling of the interactions between cells, fluid, and the channel of the device. As a first step toward building such a mathematical model, we collected video recordings of cells moving through a ridged microfluidic channel designed to compress and redirect cells according to cell biomechanics. We developed an efficient algorithm that automatically and accurately tracked the cell trajectories in the recordings. We tested the algorithm on recordings of cells with different stiffness, and showed the correlation between cell stiffness and the tracked trajectories. Moreover, the tracking algorithm successfully picked up subtle differences of cell motion when passing through consecutive ridges. The algorithm for accurately tracking cell trajectories paves the way for future efforts of modeling the flow, forces, and dynamics of cell properties in microfluidics applications.

Satellite tracking of manta rays highlights challenges to their conservation.

Directory of Open Access Journals (Sweden)

Rachel T Graham

Full Text Available We describe the real-time movements of the last of the marine mega-vertebrate taxa to be satellite tracked - the giant manta ray (or devil fish, Manta birostris, the world's largest ray at over 6 m disc width. Almost nothing is known about manta ray movements and their environmental preferences, making them one of the least understood of the marine mega-vertebrates. Red listed by the International Union for the Conservation of Nature as 'Vulnerable' to extinction, manta rays are known to be subject to direct and incidental capture and some populations are declining. Satellite-tracked manta rays associated with seasonal upwelling events and thermal fronts off the Yucatan peninsula, Mexico, and made short-range shuttling movements, foraging along and between them. The majority of locations were received from waters shallower than 50 m deep, representing thermally dynamic and productive waters. Manta rays remained in the Mexican Exclusive Economic Zone for the duration of tracking but only 12% of tracking locations were received from within Marine Protected Areas (MPAs. Our results on the spatio-temporal distribution of these enigmatic rays highlight opportunities and challenges to management efforts.

Satellite tracking of manta rays highlights challenges to their conservation.

Science.gov (United States)

Graham, Rachel T; Witt, Matthew J; Castellanos, Dan W; Remolina, Francisco; Maxwell, Sara; Godley, Brendan J; Hawkes, Lucy A

2012-01-01

We describe the real-time movements of the last of the marine mega-vertebrate taxa to be satellite tracked - the giant manta ray (or devil fish, Manta birostris), the world's largest ray at over 6 m disc width. Almost nothing is known about manta ray movements and their environmental preferences, making them one of the least understood of the marine mega-vertebrates. Red listed by the International Union for the Conservation of Nature as 'Vulnerable' to extinction, manta rays are known to be subject to direct and incidental capture and some populations are declining. Satellite-tracked manta rays associated with seasonal upwelling events and thermal fronts off the Yucatan peninsula, Mexico, and made short-range shuttling movements, foraging along and between them. The majority of locations were received from waters shallower than 50 m deep, representing thermally dynamic and productive waters. Manta rays remained in the Mexican Exclusive Economic Zone for the duration of tracking but only 12% of tracking locations were received from within Marine Protected Areas (MPAs). Our results on the spatio-temporal distribution of these enigmatic rays highlight opportunities and challenges to management efforts.

Eye tracking and the translation process

DEFF Research Database (Denmark)

Hvelplund, Kristian Tangsgaard

2014-01-01

Eye tracking has become increasingly popular as a quantitative research method in translation research. This paper discusses some of the major methodological issues involved in the use of eye tracking in translation research. It focuses specifically on challenges in the analysis and interpretation...... of eye-tracking data as reflections of cognitive processes during translation. Four types of methodological issues are discussed in the paper. The first part discusses the preparatory steps that precede the actual recording of eye-tracking data. The second part examines critically the general assumptions...... linking eye movements to cognitive processing in the context of translation research. The third part of the paper discusses two popular eye-tracking measures often used in translation research, fixations and pupil size, while the fourth part proposes a method to evaluate the quality of eye-tracking data....

Inferring animal densities from tracking data using Markov chains.

Science.gov (United States)

Whitehead, Hal; Jonsen, Ian D

2013-01-01

The distributions and relative densities of species are keys to ecology. Large amounts of tracking data are being collected on a wide variety of animal species using several methods, especially electronic tags that record location. These tracking data are effectively used for many purposes, but generally provide biased measures of distribution, because the starts of the tracks are not randomly distributed among the locations used by the animals. We introduce a simple Markov-chain method that produces unbiased measures of relative density from tracking data. The density estimates can be over a geographical grid, and/or relative to environmental measures. The method assumes that the tracked animals are a random subset of the population in respect to how they move through the habitat cells, and that the movements of the animals among the habitat cells form a time-homogenous Markov chain. We illustrate the method using simulated data as well as real data on the movements of sperm whales. The simulations illustrate the bias introduced when the initial tracking locations are not randomly distributed, as well as the lack of bias when the Markov method is used. We believe that this method will be important in giving unbiased estimates of density from the growing corpus of animal tracking data.

Inferring animal densities from tracking data using Markov chains.

Directory of Open Access Journals (Sweden)

Hal Whitehead

Full Text Available The distributions and relative densities of species are keys to ecology. Large amounts of tracking data are being collected on a wide variety of animal species using several methods, especially electronic tags that record location. These tracking data are effectively used for many purposes, but generally provide biased measures of distribution, because the starts of the tracks are not randomly distributed among the locations used by the animals. We introduce a simple Markov-chain method that produces unbiased measures of relative density from tracking data. The density estimates can be over a geographical grid, and/or relative to environmental measures. The method assumes that the tracked animals are a random subset of the population in respect to how they move through the habitat cells, and that the movements of the animals among the habitat cells form a time-homogenous Markov chain. We illustrate the method using simulated data as well as real data on the movements of sperm whales. The simulations illustrate the bias introduced when the initial tracking locations are not randomly distributed, as well as the lack of bias when the Markov method is used. We believe that this method will be important in giving unbiased estimates of density from the growing corpus of animal tracking data.

Key Questions in Marine Megafauna Movement Ecology.

Science.gov (United States)

Hays, Graeme C; Ferreira, Luciana C; Sequeira, Ana M M; Meekan, Mark G; Duarte, Carlos M; Bailey, Helen; Bailleul, Fred; Bowen, W Don; Caley, M Julian; Costa, Daniel P; Eguíluz, Victor M; Fossette, Sabrina; Friedlaender, Ari S; Gales, Nick; Gleiss, Adrian C; Gunn, John; Harcourt, Rob; Hazen, Elliott L; Heithaus, Michael R; Heupel, Michelle; Holland, Kim; Horning, Markus; Jonsen, Ian; Kooyman, Gerald L; Lowe, Christopher G; Madsen, Peter T; Marsh, Helene; Phillips, Richard A; Righton, David; Ropert-Coudert, Yan; Sato, Katsufumi; Shaffer, Scott A; Simpfendorfer, Colin A; Sims, David W; Skomal, Gregory; Takahashi, Akinori; Trathan, Philip N; Wikelski, Martin; Womble, Jamie N; Thums, Michele

2016-06-01

It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Facial feature tracking: a psychophysiological measure to assess exercise intensity?

Science.gov (United States)

Miles, Kathleen H; Clark, Bradley; Périard, Julien D; Goecke, Roland; Thompson, Kevin G

2018-04-01

The primary aim of this study was to determine whether facial feature tracking reliably measures changes in facial movement across varying exercise intensities. Fifteen cyclists completed three, incremental intensity, cycling trials to exhaustion while their faces were recorded with video cameras. Facial feature tracking was found to be a moderately reliable measure of facial movement during incremental intensity cycling (intra-class correlation coefficient = 0.65-0.68). Facial movement (whole face (WF), upper face (UF), lower face (LF) and head movement (HM)) increased with exercise intensity, from lactate threshold one (LT1) until attainment of maximal aerobic power (MAP) (WF 3464 ± 3364mm, P exercise intensities (UF minus LF at: LT1, 1048 ± 383mm; LT2, 1208 ± 611mm; MAP, 1401 ± 712mm; P exercise intensity.

Some causes of the variable shape of flocks of birds.

Directory of Open Access Journals (Sweden)

Charlotte K Hemelrijk

Full Text Available Flocks of birds are highly variable in shape in all contexts (while travelling, avoiding predation, wheeling above the roost. Particularly amazing in this respect are the aerial displays of huge flocks of starlings (Sturnus vulgaris above the sleeping site at dawn. The causes of this variability are hardly known, however. Here we hypothesise that variability of shape increases when there are larger local differences in movement behaviour in the flock. We investigate this hypothesis with the help of a model of the self-organisation of travelling groups, called StarDisplay, since such a model has also increased our understanding of what causes the oblong shape of schools of fish. The flocking patterns in the model prove to resemble those of real birds, in particular of starlings and rock doves. As to shape, we measure the relative proportions of the flock in several ways, which either depend on the direction of movement or do not. We confirm that flock shape is usually more variable when local differences in movement in the flock are larger. This happens when a flock size is larger, b interacting partners are fewer, c the flock turnings are stronger, and d individuals roll into the turn. In contrast to our expectations, when variability of speed in the flock is higher, flock shape and the positions of members in the flock are more static. We explain this and indicate the adaptive value of low variability of speed and spatial restriction of interaction and develop testable hypotheses.

Influence of quantum dot labels on single molecule movement in the plasma membrane

DEFF Research Database (Denmark)

Clausen, Mathias P.; Lagerholm, B. Christoffer

2011-01-01

Single particle tracking results are very dependent on the probe that is used. In this study we have investigated the influence that functionalized quantum dots (QDs) have on the recorded movement in single molecule tracking experiments of plasma membrane species in live cells. Potential issues...... for simultaneous investigations of different plasma membrane species in order to discriminate the effect of the label from differences in movement of the target molecules....

Moving in the Anthropocene: Global reductions in terrestrial mammalian movements

OpenAIRE

Boehning-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

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 cha...

Single-organelle tracking by two-photon conversion

Science.gov (United States)

Watanabe, Wataru; Shimada, Tomoko; Matsunaga, Sachihiro; Kurihara, Daisuke; Fukui, Kiichi; Shin-Ichi Arimura, Shin-Ichi; Tsutsumi, Nobuhiro; Isobe, Keisuke; Itoh, Kazuyoshi

2007-03-01

Spatial and temporal information about intracellular objects and their dynamics within a living cell are essential for dynamic analysis of such objects in cell biology. A specific intracellular object can be discriminated by photoactivatable fluorescent proteins that exhibit pronounced light-induced spectral changes. Here, we report on selective labeling and tracking of a single organelle by using two-photon conversion of a photoconvertible fluorescent protein with near-infrared femtosecond laser pulses. We performed selective labeling of a single mitochondrion in a living tobacco BY-2 cell using two-photon photoconversion of Kaede. Using this technique, we demonstrated that, in plants, the directed movement of individual mitochondria along the cytoskeletons was mediated by actin filaments, whereas microtubules were not required for the movement of mitochondria. This single-organelle labeling technique enabled us to track the dynamics of a single organelle, revealing the mechanisms involved in organelle dynamics. The technique has potential application in direct tracking of selective cellular and intracellular structures.

3-D model-based vehicle tracking.

Science.gov (United States)

Lou, Jianguang; Tan, Tieniu; Hu, Weiming; Yang, Hao; Maybank, Steven J

2005-10-01

This paper aims at tracking vehicles from monocular intensity image sequences and presents an efficient and robust approach to three-dimensional (3-D) model-based vehicle tracking. Under the weak perspective assumption and the ground-plane constraint, the movements of model projection in the two-dimensional image plane can be decomposed into two motions: translation and rotation. They are the results of the corresponding movements of 3-D translation on the ground plane (GP) and rotation around the normal of the GP, which can be determined separately. A new metric based on point-to-line segment distance is proposed to evaluate the similarity between an image region and an instantiation of a 3-D vehicle model under a given pose. Based on this, we provide an efficient pose refinement method to refine the vehicle's pose parameters. An improved EKF is also proposed to track and to predict vehicle motion with a precise kinematics model. Experimental results with both indoor and outdoor data show that the algorithm obtains desirable performance even under severe occlusion and clutter.

Tracking the Evolution of Smartphone Sensing for Monitoring Human Movement

Science.gov (United States)

del Rosario, Michael B.; Redmond, Stephen J.; Lovell, Nigel H.

2015-01-01

Advances in mobile technology have led to the emergence of the “smartphone”, a new class of device with more advanced connectivity features that have quickly made it a constant presence in our lives. Smartphones are equipped with comparatively advanced computing capabilities, a global positioning system (GPS) receivers, and sensing capabilities (i.e., an inertial measurement unit (IMU) and more recently magnetometer and barometer) which can be found in wearable ambulatory monitors (WAMs). As a result, algorithms initially developed for WAMs that “count” steps (i.e., pedometers); gauge physical activity levels; indirectly estimate energy expenditure and monitor human movement can be utilised on the smartphone. These algorithms may enable clinicians to “close the loop” by prescribing timely interventions to improve or maintain wellbeing in populations who are at risk of falling or suffer from a chronic disease whose progression is linked to a reduction in movement and mobility. The ubiquitous nature of smartphone technology makes it the ideal platform from which human movement can be remotely monitored without the expense of purchasing, and inconvenience of using, a dedicated WAM. In this paper, an overview of the sensors that can be found in the smartphone are presented, followed by a summary of the developments in this field with an emphasis on the evolution of algorithms used to classify human movement. The limitations identified in the literature will be discussed, as well as suggestions about future research directions. PMID:26263998

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

Science.gov (United States)

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

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

Science.gov (United States)

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

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

Directory of Open Access Journals (Sweden)

Natalia Stefanini Da Silveira

Full Text Available 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

GPS tracking data of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast

NARCIS (Netherlands)

Stienen, E.W.M.; Desmet, P.; Aelterman, B.; Courtens, W.; Feys, S.; Vanermen, N.; Verstraete, H.; Van de Walle, M.; Deneudt, K.; Hernandez, F.; Houthoofdt, R.; Vanhoorne, B.; Bouten, W.; Buijs, R.-J.; Kavelaars, M.M.; Müller, W.; Herman, D.; Matheve, H.; Sotillo, A.; Lens, L.

2016-01-01

In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5

A Comparitive Analysis of the Influence of Weather on the Flight Altitudes of Birds.

Science.gov (United States)

Shamoun-Baranes, Judy; van Loon, Emiel; van Gasteren, Hans; van Belle, Jelmer; Bouten, Willem; Buurma, Luit

2006-01-01

Birds pose a serious risk to flight safety worldwide. A Bird Avoidance Model (BAM) is being developed in the Netherlands to reduce the risk of bird aircraft collisions. In order to develop a temporally and spatially dynamic model of bird densities, data are needed on the flight-altitude distribution of birds and how this is influenced by weather. This study focuses on the dynamics of flight altitudes of several species of birds during local flights over land in relation to meteorological conditions.We measured flight altitudes of several species in the southeastern Netherlands using tracking radar during spring and summer 2000. Representatives of different flight strategy groups included four species: a soaring species (buzzard ), an obligatory aerial forager (swift Apus apus), a flapping and gliding species (blackheaded gull Larus ridibundus), and a flapping species (starling Sturnus vulgaris).Maximum flight altitudes varied among species, during the day and among days. Weather significantly influenced the flight altitudes of all species studied. Factors such as temperature, relative humidity, atmospheric instability, cloud cover, and sea level pressure were related to flight altitudes. Different combinations of factors explained 40% 70% of the variance in maximum flight altitudes. Weather affected flight strategy groups differently. Compared to flapping species, buzzards and swifts showed stronger variations in maximum daily altitude and f lew higher under conditions reflecting stronger thermal convection. The dynamic vertical distributions of birds are important for risk assessment and mitigation measures in flight safety as well as wind turbine studies.

Guam and the Northern Mariana Islands ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for pelagic birds, shorebirds, wading birds, waterfowl, gulls, terns, and passerine birds in Guam and the...

Efficient Dynamic Adaptation Strategies for Object Tracking Tree in Wireless Sensor Network

Directory of Open Access Journals (Sweden)

CHEN, M.

2012-12-01

Full Text Available Most object tracking trees are established using the predefined mobility profile. However, when the real object's movement behaviors and query rates are different from the predefined mobility profile and query rates, the update cost and query cost of object tracking tree may increase. To upgrade the object tracking tree, the sink needs to send very large messages to collect the real movement information from the network, introducing a very large message overhead, which is referred to as adaptation cost. The Sub Root Message-Tree Adaptive procedure was proposed to dynamically collect the real movement information under the sub-tree and reconstruct the sub-tree to provide good performance based on the collected information. The simulation results indicates that the Sub Root Message-Tree Adaptive procedure is sufficient to achieve good total cost and lower adaptation cost.

A laser-based eye-tracking system.

Science.gov (United States)

Irie, Kenji; Wilson, Bruce A; Jones, Richard D; Bones, Philip J; Anderson, Tim J

2002-11-01

This paper reports on the development of a new eye-tracking system for noninvasive recording of eye movements. The eye tracker uses a flying-spot laser to selectively image landmarks on the eye and, subsequently, measure horizontal, vertical, and torsional eye movements. Considerable work was required to overcome the adverse effects of specular reflection of the flying-spot from the surface of the eye onto the sensing elements of the eye tracker. These effects have been largely overcome, and the eye-tracker has been used to document eye movement abnormalities, such as abnormal torsional pulsion of saccades, in the clinical setting.

Towards free 3D end-point control for robotic-assisted human reaching using binocular eye tracking.

Science.gov (United States)

Maimon-Dror, Roni O; Fernandez-Quesada, Jorge; Zito, Giuseppe A; Konnaris, Charalambos; Dziemian, Sabine; Faisal, A Aldo

2017-07-01

Eye-movements are the only directly observable behavioural signals that are highly correlated with actions at the task level, and proactive of body movements and thus reflect action intentions. Moreover, eye movements are preserved in many movement disorders leading to paralysis (or amputees) from stroke, spinal cord injury, Parkinson's disease, multiple sclerosis, and muscular dystrophy among others. Despite this benefit, eye tracking is not widely used as control interface for robotic interfaces in movement impaired patients due to poor human-robot interfaces. We demonstrate here how combining 3D gaze tracking using our GT3D binocular eye tracker with custom designed 3D head tracking system and calibration method enables continuous 3D end-point control of a robotic arm support system. The users can move their own hand to any location of the workspace by simple looking at the target and winking once. This purely eye tracking based system enables the end-user to retain free head movement and yet achieves high spatial end point accuracy in the order of 6 cm RMSE error in each dimension and standard deviation of 4 cm. 3D calibration is achieved by moving the robot along a 3 dimensional space filling Peano curve while the user is tracking it with their eyes. This results in a fully automated calibration procedure that yields several thousand calibration points versus standard approaches using a dozen points, resulting in beyond state-of-the-art 3D accuracy and precision.

The Apache Longbow-Hellfire Missile Test at Yuma Proving Ground: Ecological Risk Assessment for Tracked Vehicle Movement across Desert Pavement

International Nuclear Information System (INIS)

Peterson, Mark J; Efroymson, Rebecca Ann; Hargrove, William Walter

2008-01-01

A multiple stressor risk assessment was conducted at Yuma Proving Ground, Arizona, as a demonstration of the Military Ecological Risk Assessment Framework. The focus was a testing program at Cibola Range, which involved an Apache Longbow helicopter firing Hellfire missiles at moving targets, M60-A1 tanks. This paper describes the ecological risk assessment for the tracked vehicle movement component of the testing program. The principal stressor associated with tracked vehicle movement was soil disturbance, and a resulting, secondary stressor was hydrological change. Water loss to washes and wash vegetation was expected to result from increased infiltration and/or evaporation associated with disturbances to desert pavement. The simulated exposure of wash vegetation to water loss was quantified using estimates of exposed land area from a digital ortho quarter quad aerial photo and field observations, a 30 30 m digital elevation model, the flow accumulation feature of ESRI ArcInfo, and a two-step process in which runoff was estimated from direct precipitation to a land area and from water that flowed from upgradient to a land area. In all simulated scenarios, absolute water loss decreased with distance from the disturbance, downgradient in the washes; however, percentage water loss was greatest in land areas immediately downgradient of a disturbance. Potential effects on growth and survival of wash trees were quantified by using an empirical relationship derived from a local unpublished study of water infiltration rates. The risk characterization concluded that neither risk to wash vegetation growth or survival nor risk to mule deer abundance and reproduction was expected. The risk characterization was negative for both the incremental risk of the test program and the combination of the test and pretest disturbances

Rhode Island, Connecticut, New York, and New Jersey ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, passerine birds, gulls and...

Spatial memory and animal movement.

Science.gov (United States)

Fagan, William F; Lewis, Mark A; Auger-Méthé, Marie; Avgar, Tal; Benhamou, Simon; Breed, Greg; LaDage, Lara; Schlägel, Ulrike E; Tang, Wen-wu; Papastamatiou, Yannis P; Forester, James; Mueller, Thomas

2013-10-01

Memory is critical to understanding animal movement but has proven challenging to study. Advances in animal tracking technology, theoretical movement models and cognitive sciences have facilitated research in each of these fields, but also created a need for synthetic examination of the linkages between memory and animal movement. Here, we draw together research from several disciplines to understand the relationship between animal memory and movement processes. First, we frame the problem in terms of the characteristics, costs and benefits of memory as outlined in psychology and neuroscience. Next, we provide an overview of the theories and conceptual frameworks that have emerged from behavioural ecology and animal cognition. Third, we turn to movement ecology and summarise recent, rapid developments in the types and quantities of available movement data, and in the statistical measures applicable to such data. Fourth, we discuss the advantages and interrelationships of diverse modelling approaches that have been used to explore the memory-movement interface. Finally, we outline key research challenges for the memory and movement communities, focusing on data needs and mathematical and computational challenges. We conclude with a roadmap for future work in this area, outlining axes along which focused research should yield rapid progress. © 2013 John Wiley & Sons Ltd/CNRS.

Open-Ended Measurement of Whole-Body Movement: A Feasibility Study

Directory of Open Access Journals (Sweden)

Finn, Michael T. M.

2018-02-01

Full Text Available As the importance of embodiment emerges for psychology, there is a need to advance methodology for measuring the dynamics of movement in an open-ended fashion. Such a tool should be versatile across contexts and track spontaneous and natural movement with minimal constraints. We test the feasibility of a method for measuring whole-body movement over time that attempts to meet this need. We use a motion capture system comprised of two Microsoft Kinect version 2.0 cameras and iPiSoft Motion Capture software, and compare its estimates of magnitude rotational velocity and whole-body movement complexity (multivariate multiscale sample entropy; MMSE to that of a gold standard motion capture system across a variety of movement sequences. The candidate system satisfactorily estimated the instantaneous velocity of 13 body segments in agreement with the gold standard system across movement sequences demonstrating initial feasibility of this process. Summary calculations of velocity by sequence and MMSE calculations were also in high agreement with the gold standard, crucially suggesting that the candidate system could pick up on the complex dynamics of movement over time. The candidate system was feasible and demonstrates preliminary validity for general use in the tracking of continuous human movement for clinical and experimental psychology. We also provide R code and sample data for the importing and processing of movement data exported from iPiSoft Motion Capture Studio.

The dynamics of fauna and population of birds in agricultural landscapes on the border of Kazan International Airport

Science.gov (United States)

Bespalov, A. F.; Belyaev, A. N.

2018-01-01

The dynamics of fauna and population of birds from agricultural lands near Kazan International Airport has been studied for one year. A total of 60 bird species have been registered, of which 26 species must be considered as highly dangerous to flying aircraft. With regard to seasonal activity, the nesting period (April - June) is the most hazardous, since it is characterized by maximum species richness and total population density of birds, as well as their high species diversity. Furthermore, a serious danger is posed by the period of postnesting nomadic movements and the onset of migrations (July - September) when the species diversity turns out to be the highest and the total population density begins to decrease. It has been recommended based on the obtained results that the current crops should be replaced by cultivars that will be less attractive to birds. In spring and autumn, certain bird hazing and frightening measures must be taken on a more regular basis.

Drug metabolism in birds

Science.gov (United States)

Pan, Huo Ping; Fouts, James R.

1979-01-01

Papers published over 100 years since the beginning of the scientific study of drug metabolism in birds were reviewed. Birds were found to be able to accomplish more than 20 general biotransformation reactions in both functionalization and conjugation. Chickens were the primary subject of study but over 30 species of birds were used. Large species differences in drug metabolism exist between birds and mammals as well as between various birds, these differences were mostly quantitative. Qualitative differences were rare. On the whole, drug metabolism studies in birds have been neglected as compared with similar studies on insects and mammals. The uniqueness of birds and the advantages of using birds in drug metabolism studies are discussed. Possible future studies of drug metabolism in birds are recommended.

Fluorescence-tracking of activation gating in human ERG channels reveals rapid S4 movement and slow pore opening.

Directory of Open Access Journals (Sweden)

Zeineb Es-Salah-Lamoureux

2010-05-01

Full Text Available hERG channels are physiologically important ion channels which mediate cardiac repolarization as a result of their unusual gating properties. These are very slow activation compared with other mammalian voltage-gated potassium channels, and extremely rapid inactivation. The mechanism of slow activation is not well understood and is investigated here using fluorescence as a direct measure of S4 movement and pore opening.Tetramethylrhodamine-5-maleimide (TMRM fluorescence at E519 has been used to track S4 voltage sensor movement, and channel opening and closing in hERG channels. Endogenous cysteines (C445 and C449 in the S1-S2 linker bound TMRM, which caused a 10 mV hyperpolarization of the V((1/2 of activation to -27.5+/-2.0 mV, and showed voltage-dependent fluorescence signals. Substitution of S1-S2 linker cysteines with valines allowed unobstructed recording of S3-S4 linker E519C and L520C emission signals. Depolarization of E519C channels caused rapid initial fluorescence quenching, fit with a double Boltzmann relationship, F-V(ON, with V((1/2 (,1 = -37.8+/-1.7 mV, and V((1/2 (,2 = 43.5+/-7.9 mV. The first phase, V((1/2 (,1, was approximately 20 mV negative to the conductance-voltage relationship measured from ionic tail currents (G-V((1/2 = -18.3+/-1.2 mV, and relatively unchanged in a non-inactivating E519C:S620T mutant (V((1/2 = -34.4+/-1.5 mV, suggesting the fast initial fluorescence quenching tracked S4 voltage sensor movement. The second phase of rapid quenching was absent in the S620T mutant. The E519C fluorescence upon repolarization (V((1/2 = -20.6+/-1.2, k = 11.4 mV and L520C quenching during depolarization (V((1/2 = -26.8+/-1.0, k = 13.3 mV matched the respective voltage dependencies of hERG ionic tails, and deactivation time constants from -40 to -110 mV, suggesting they detected pore-S4 rearrangements related to ionic current flow during pore opening and closing.THE DATA INDICATE: 1 that rapid environmental changes occur at the

Eye tracking for visual marketing

NARCIS (Netherlands)

Wedel, M.; Pieters, R.

2008-01-01

We provide the theory of visual attention and eye-movements that serves as a basis for evaluating eye-tracking research and for discussing salient and emerging issues in visual marketing. Motivated from its rising importance in marketing practice and its potential for theoretical contribution, we

Sand dune tracking from satellite laser altimetry

Science.gov (United States)

Dabboor, Mohammed

Substantial problems arise from sand movement in arid and semi-arid countries. Sand poses a threat to infrastructure, agricultural and urban areas. These issues are caused by the encroachment of sand on roads and railway tracks, farmland, towns and villages, and airports, to name a few. Sand movement highly depends on geomorphology including vegetation cover, shape and height of the terrain, and grain size of the sand. However, wind direction and speed are the most important factors that affect efficient sand movement. The direction of the movement depends on the main direction of the wind, but it has been shown that a minimum wind speed is required, e.g. wind gusts, to initiate sand transport. This fact prevents a simple calculation of sand transport from conventional wind data as wind records rarely contain sub-minute intervals masking out any wind gusts. An alternative of predicting sand transport is the direct observation of sand advance by in situ measurements or via satellite. Until recently, satellite imagery was the only means to compare dune shape and position for predicting dune migration over several years. In 2003, the NASA laser altimetry mission ICESat became operational and monitors elevations over all surface types including sand dunes with an accuracy of about 10-20 cm. In this study, ICESat observations from repeat tracks (tracks overlapping eachother within 50 m) are used to derive sand dune advance and direction. The method employs a correlation of the elevation profiles over several dunes and was sucessfully validated with synthetic data. The accuracy of this method is 5 meters of dune advance. One of the most active areas exhibiting sand and dune movement is the area of the Arabian Peninsula. Approximately one-third of the Arabian Peninsula is covered by sand dunes. Different wind regimes (Shamal, Kaus) cause sand dune movement in the selected study area in the eastern part of the Arabian Peninsula between 20-25 degrees North and 45-55 degrees

EYE GAZE TRACKING

DEFF Research Database (Denmark)

2017-01-01

This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of: detecting the position of at least three reflections on said eye, transforming said positions to spanning...... a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation, detecting the position of said center of the eye relative to the position...... of said reflections and transforming this position to said normalized coordinate system, tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system. Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided...

Apparatus and method for tracking a molecule or particle in three dimensions

Science.gov (United States)

Werner, James H [Los Alamos, NM; Goodwin, Peter M [Los Alamos, NM; Lessard, Guillaume [Santa Fe, NM

2009-03-03

An apparatus and method were used to track the movement of fluorescent particles in three dimensions. Control software was used with the apparatus to implement a tracking algorithm for tracking the motion of the individual particles in glycerol/water mixtures. Monte Carlo simulations suggest that the tracking algorithms in combination with the apparatus may be used for tracking the motion of single fluorescent or fluorescently labeled biomolecules in three dimensions.

Identifying Typical Movements Among Indoor Objects

DEFF Research Database (Denmark)

Radaelli, Laura; Sabonis, Dovydas; Lu, Hua

2013-01-01

With the proliferation of mobile computing, positioning systems are becoming available that enable indoor location-based services. As a result, indoor tracking data is also becoming available. This paper puts focus on one use of such data, namely the identification of typical movement patterns...

Two-axis tracking using translation stages for a lens-to-channel waveguide solar concentrator.

Science.gov (United States)

Liu, Yuxiao; Huang, Ran; Madsen, Christi K

2014-10-20

A two-axis tracking scheme designed for tracker and a translation stage is discussed. The translation stage is used for adjusting positions for seasonal sun movement. It has two-dimensional x-y tracking instead of horizontal movement x-only. This tracking method is compatible with planar waveguide solar concentrators. A prototype system with 50x concentration shows >75% optical efficiency throughout the year in simulation and >65% efficiency experimentally. This efficiency can be further improved by the use of anti-reflection layers and a larger waveguide refractive index.

Interactive Sonification of Spontaneous Movement of Children-Cross-Modal Mapping and the Perception of Body Movement Qualities through Sound.

Science.gov (United States)

Frid, Emma; Bresin, Roberto; Alborno, Paolo; Elblaus, Ludvig

2016-01-01

In this paper we present three studies focusing on the effect of different sound models in interactive sonification of bodily movement. We hypothesized that a sound model characterized by continuous smooth sounds would be associated with other movement characteristics than a model characterized by abrupt variation in amplitude and that these associations could be reflected in spontaneous movement characteristics. Three subsequent studies were conducted to investigate the relationship between properties of bodily movement and sound: (1) a motion capture experiment involving interactive sonification of a group of children spontaneously moving in a room, (2) an experiment involving perceptual ratings of sonified movement data and (3) an experiment involving matching between sonified movements and their visualizations in the form of abstract drawings. In (1) we used a system constituting of 17 IR cameras tracking passive reflective markers. The head positions in the horizontal plane of 3-4 children were simultaneously tracked and sonified, producing 3-4 sound sources spatially displayed through an 8-channel loudspeaker system. We analyzed children's spontaneous movement in terms of energy-, smoothness- and directness-index. Despite large inter-participant variability and group-specific effects caused by interaction among children when engaging in the spontaneous movement task, we found a small but significant effect of sound model. Results from (2) indicate that different sound models can be rated differently on a set of motion-related perceptual scales (e.g., expressivity and fluidity). Also, results imply that audio-only stimuli can evoke stronger perceived properties of movement (e.g., energetic, impulsive) than stimuli involving both audio and video representations. Findings in (3) suggest that sounds portraying bodily movement can be represented using abstract drawings in a meaningful way. We argue that the results from these studies support the existence of a

Interactive Sonification of Spontaneous Movement of Children—Cross-Modal Mapping and the Perception of Body Movement Qualities through Sound

Science.gov (United States)

Frid, Emma; Bresin, Roberto; Alborno, Paolo; Elblaus, Ludvig

2016-01-01

In this paper we present three studies focusing on the effect of different sound models in interactive sonification of bodily movement. We hypothesized that a sound model characterized by continuous smooth sounds would be associated with other movement characteristics than a model characterized by abrupt variation in amplitude and that these associations could be reflected in spontaneous movement characteristics. Three subsequent studies were conducted to investigate the relationship between properties of bodily movement and sound: (1) a motion capture experiment involving interactive sonification of a group of children spontaneously moving in a room, (2) an experiment involving perceptual ratings of sonified movement data and (3) an experiment involving matching between sonified movements and their visualizations in the form of abstract drawings. In (1) we used a system constituting of 17 IR cameras tracking passive reflective markers. The head positions in the horizontal plane of 3–4 children were simultaneously tracked and sonified, producing 3–4 sound sources spatially displayed through an 8-channel loudspeaker system. We analyzed children's spontaneous movement in terms of energy-, smoothness- and directness-index. Despite large inter-participant variability and group-specific effects caused by interaction among children when engaging in the spontaneous movement task, we found a small but significant effect of sound model. Results from (2) indicate that different sound models can be rated differently on a set of motion-related perceptual scales (e.g., expressivity and fluidity). Also, results imply that audio-only stimuli can evoke stronger perceived properties of movement (e.g., energetic, impulsive) than stimuli involving both audio and video representations. Findings in (3) suggest that sounds portraying bodily movement can be represented using abstract drawings in a meaningful way. We argue that the results from these studies support the existence of a

Correlation between anatomic foot and ankle movement measured with MRI and with a motion analysis system.

Science.gov (United States)

Marquez-Barrientos, C; Liu, X C; Lyon, R; Tassone, C; Thometz, J; Tarima, S

2012-07-01

Several studies have attempted to measure how well external markers track internal bone movement using pins drilled into the foot, but this is too invasive for the pediatric population. This study investigated how well a six segment foot model (6SFM) using external markers was able to measure bone movement in the foot compared to MRI measurements. The foot was moved into different positions using a plastic foot jig and measurements were taken with both systems. The aims were to: (1) Look at the correlation between movement tracked with an Electronic Motion Tracking System (EMTS) and by measurements derived from MRI images, specifically the principal intercept angles (PIAs) which are the angles of intersection between principal axes of inertia of bone volumes. (2) To see how well external motion measured by the 6SFM could predict PIAs. Four bone pairs had their movement tracked: Tibia-Calcaneus, Calcaneus-Cuboid, Navicular-1st Metatarsal, and 1st Metatarsal-Hallux. The results showed moderate correlation between measured PIAs and those predicted at the Tibia-Calcaneus, Navicular-1st Metatarsal, and 1st Metatarsal-Hallux joints. Moderate to high correlation was found between the PIA and movement in a single anatomic plane for all four joints at several positions. The 6SFM using the EMTS allows reliable tracking of 3D rotations in the pediatric foot, except at the Calcaneus-Cuboid joint. Copyright © 2012 Elsevier B.V. All rights reserved.

Eye-Tracking Study of Complexity in Gas Law Problems

Science.gov (United States)

Tang, Hui; Pienta, Norbert

2012-01-01

This study, part of a series investigating students' use of online tools to assess problem solving, uses eye-tracking hardware and software to explore the effect of problem difficulty and cognitive processes when students solve gas law word problems. Eye movements are indices of cognition; eye-tracking data typically include the location,…

Breeding Dispersal by Birds in a Dynamic Urban Ecosystem.

Science.gov (United States)

Marzluff, John M; DeLap, Jack H; Oleyar, M David; Whittaker, Kara A; Gardner, Beth

2016-01-01

Changes in land cover during urbanization profoundly affect the diversity of bird communities, but the demographic mechanisms affecting diversity are poorly known. We advance such understanding by documenting how urbanization influences breeding dispersal-the annual movement of territorial adults-of six songbird species in the Seattle, WA, USA metropolitan area. We color-banded adults and mapped the centers of their annual breeding activities from 2000-2010 to obtain 504 consecutive movements by 337 adults. By comparing movements, annual reproduction, and mate fidelity among 10 developed, 5 reserved, and 11 changing (areas cleared and developed during our study) landscapes, we determined that adaptive breeding dispersal of sensitive forest species (Swainson's Thrush and Pacific wren), which involves shifting territory and mate after reproductive failure, was constrained by development. In changing lands, sensitive forest specialists dispersed from active development to nearby forested areas, but in so doing suffered low annual reproduction. Species tolerant of suburban lands (song sparrow, spotted towhee, dark-eyed junco, and Bewick's wren) dispersed adaptively in changing landscapes. Site fidelity ranged from 0% (Pacific wren in changing landscape) to 83% (Bewick's wren in forest reserve). Mate fidelity ranged from 25% (dark-eyed junco) to 100% (Bewick's wren). Variation in fidelity to mate and territory was consistent with theories positing an influence of territory quality, asynchronous return from migration, prior productivity, and reproductive benefits of retaining a familiar territory. Costly breeding dispersal, as well as reduced reproductive success and lowered survival cause some birds to decline in the face of urbanization. In contrast, the ability of species that utilize edges and early successional habitats to breed successfully, disperse to improve reproductive success after failure, and survive throughout the urban ecosystem enables them to maintain

Breeding Dispersal by Birds in a Dynamic Urban Ecosystem.

Directory of Open Access Journals (Sweden)

John M Marzluff

Full Text Available Changes in land cover during urbanization profoundly affect the diversity of bird communities, but the demographic mechanisms affecting diversity are poorly known. We advance such understanding by documenting how urbanization influences breeding dispersal-the annual movement of territorial adults-of six songbird species in the Seattle, WA, USA metropolitan area. We color-banded adults and mapped the centers of their annual breeding activities from 2000-2010 to obtain 504 consecutive movements by 337 adults. By comparing movements, annual reproduction, and mate fidelity among 10 developed, 5 reserved, and 11 changing (areas cleared and developed during our study landscapes, we determined that adaptive breeding dispersal of sensitive forest species (Swainson's Thrush and Pacific wren, which involves shifting territory and mate after reproductive failure, was constrained by development. In changing lands, sensitive forest specialists dispersed from active development to nearby forested areas, but in so doing suffered low annual reproduction. Species tolerant of suburban lands (song sparrow, spotted towhee, dark-eyed junco, and Bewick's wren dispersed adaptively in changing landscapes. Site fidelity ranged from 0% (Pacific wren in changing landscape to 83% (Bewick's wren in forest reserve. Mate fidelity ranged from 25% (dark-eyed junco to 100% (Bewick's wren. Variation in fidelity to mate and territory was consistent with theories positing an influence of territory quality, asynchronous return from migration, prior productivity, and reproductive benefits of retaining a familiar territory. Costly breeding dispersal, as well as reduced reproductive success and lowered survival cause some birds to decline in the face of urbanization. In contrast, the ability of species that utilize edges and early successional habitats to breed successfully, disperse to improve reproductive success after failure, and survive throughout the urban ecosystem enables them

Capturing human movement patterns in public spaces

DEFF Research Database (Denmark)

Nielsen, Søren Zebitz; Gade, Rikke

2014-01-01

Non-intrusive and non-privacy violating tracking of people by the use of thermal cameras and Computer Vision The video shows examples of data collection of pedestrian tracks in an urban plaza using a thermal camera. The data is used in my PhD project on Human Movement Patterns in Smart Cities....... The recording and analysis of the thermal videos has been made in collaboration with Rikke Gade from the Visual Analytics of People Lab at Aalborg University....

Self-tracking optical beam monitor

International Nuclear Information System (INIS)

Miyahara, T.; Mitsuhashi, T.

1992-01-01

A new optical beam monitor with a self-tracking system was constructed and tested at an undulator beam line of the Photon Factory. The monitor has a feedback system to receive a constant part of the radiation and gives a large range of linearity. The beam position is read out through a linear encoder to detect the self-tracking movement of a pair of photocathodes. The monitor except the feedback system is totally bakeable and UHV compatible and can be installed at a VUV or a soft x-ray beam line

Saving our shared birds: Partners in Flight tri-national vision for landbird conservation

Science.gov (United States)

Berlanga, Humberto; Kennedy, Judith A.; Rich, Terrell D.; Arizmendi, Maria del Coro; Beardmore, Carol J.; Blancher, Peter J.; Butcher, Gregory S.; Couturier, Andrew R.; Dayer, Ashley A.; Demarest, Dean W.; Easton, Wendy E.; Gustafson, Mary; Iñigo-Elias, Eduardo E.; Krebs, Elizabeth A.; Panjabi, Arvind O.; Rodriguez Contreras, Vicente; Rosenberg, Kenneth V.; Ruth, Janet M.; Santana Castellon, Eduardo; Vidal, Rosa Ma.; Will, Tom

2010-01-01

Landbirds are the most abundant and diverse group of birds in North America, with nearly 900 species distributed across every major terrestrial habitat. Birds are indicators of environmental health; their populations track changes in habitat, water, disease, and climate. They are providers of invaluable ecosystem services, such as pest control, seed dispersal, and pollination. As the focus of bird watching, they help generate billions of dollars for national economies. Yet, we are in danger of losing this spectacular and irreplaceable bird diversity: landbirds are experiencing significant declines, ominous threats, and shrinking habitats across a continent with growing human populations, increasing resource consumption, and changing climate. Saving Our Shared Birds presents for the first time a comprehensive conservation assessment of landbirds in Canada, Mexico, and the continental United States. This new tri-national vision encompasses the complete range of many migratory species and highlights the vital links among migrants and highly threatened resident species in Mexico. It points to a set of continent-scale actions necessary to maintain the landbird diversity and abundance that are our shared responsibility. This collaborative effort of Partners in Flight (PIF) is the next step in linking the countries of the Western Hemisphere to help species at risk and keep common birds common through voluntary partnerships—our mission since 1990. Saving Our Shared Birds builds upon PIF’s 2004 North American Landbird Conservation Plan, which presented science-based priorities for the conservation of 448 landbird species in Canada and the United States. Our three nations have expressed their commitment to cooperative conservation through numerous international treaties, agreements, and programs, including formation of the North American Bird Conservation Initiative (NABCI) a decade ago. The NABCI partnership recognizes that effective conservation requires a concerted

Admittance-Based Upper Limb Robotic Active and Active-Assistive Movements

Directory of Open Access Journals (Sweden)

Cristóbal Ochoa Luna

2015-09-01

Full Text Available This paper presents two rehabilitation schemes for patients with upper limb impairments. The first is an active-assistive scheme based on the trajectory tracking of predefined paths in Cartesian space. In it, the system allows for an adjustable degree of variation with respect to ideal tracking. The amount of variation is determined through an admittance function that depends on the opposition forces exerted on the system by the user, due to possible impairments. The coefficients of the function allow the adjustment of the degree of assistance the robot will provide in order to complete the target trajectory. The second scheme corresponds to active movements in a constrained space. Here, the same admittance function is applied; however, in this case, it is unattached to a predefined trajectory and instead connected to one generated in real time, according to the user's intended movements. This allows the user to move freely with the robot in order to track a given path. The free movement is bounded through the use of virtual walls that do not allow users to exceed certain limits. A human-machine interface was developed to guide the robot's user.

Birds of Sabaki Birds of Sabaki

African Journals Online (AJOL)

CJ

2005-02-25

Feb 25, 2005 ... covers approximately 250ha.The area encompassed by this study extends from Mambrui to the north, the sea to the east, the opposite bank of the estuary to the south and the Sabaki bridge and Malindi-Garsen road to the west. The area is defined as an Important Bird Area(IBA) by BirdLife International in ...

Synchronizing the tracking eye movements with the motion of a visual target: Basic neural processes.

Science.gov (United States)

Goffart, Laurent; Bourrelly, Clara; Quinet, Julie

2017-01-01

In primates, the appearance of an object moving in the peripheral visual field elicits an interceptive saccade that brings the target image onto the foveae. This foveation is then maintained more or less efficiently by slow pursuit eye movements and subsequent catch-up saccades. Sometimes, the tracking is such that the gaze direction looks spatiotemporally locked onto the moving object. Such a spatial synchronism is quite spectacular when one considers that the target-related signals are transmitted to the motor neurons through multiple parallel channels connecting separate neural populations with different conduction speeds and delays. Because of the delays between the changes of retinal activity and the changes of extraocular muscle tension, the maintenance of the target image onto the fovea cannot be driven by the current retinal signals as they correspond to past positions of the target. Yet, the spatiotemporal coincidence observed during pursuit suggests that the oculomotor system is driven by a command estimating continuously the current location of the target, i.e., where it is here and now. This inference is also supported by experimental perturbation studies: when the trajectory of an interceptive saccade is experimentally perturbed, a correction saccade is produced in flight or after a short delay, and brings the gaze next to the location where unperturbed saccades would have landed at about the same time, in the absence of visual feedback. In this chapter, we explain how such correction can be supported by previous visual signals without assuming "predictive" signals encoding future target locations. We also describe the basic neural processes which gradually yield the synchronization of eye movements with the target motion. When the process fails, the gaze is driven by signals related to past locations of the target, not by estimates to its upcoming locations, and a catch-up is made to reinitiate the synchronization. © 2017 Elsevier B.V. All rights

Impedance modulation and feedback corrections in tracking targets of variable size and frequency.

Science.gov (United States)

Selen, Luc P J; van Dieën, Jaap H; Beek, Peter J

2006-11-01

Humans are able to adjust the accuracy of their movements to the demands posed by the task at hand. The variability in task execution caused by the inherent noisiness of the neuromuscular system can be tuned to task demands by both feedforward (e.g., impedance modulation) and feedback mechanisms. In this experiment, we studied both mechanisms, using mechanical perturbations to estimate stiffness and damping as indices of impedance modulation and submovement scaling as an index of feedback driven corrections. Eight subjects tracked three differently sized targets (0.0135, 0.0270, and 0.0405 rad) moving at three different frequencies (0.20, 0.25, and 0.33 Hz). Movement variability decreased with both decreasing target size and movement frequency, whereas stiffness and damping increased with decreasing target size, independent of movement frequency. These results are consistent with the theory that mechanical impedance acts as a filter of noisy neuromuscular signals but challenge stochastic theories of motor control that do not account for impedance modulation and only partially for feedback control. Submovements during unperturbed cycles were quantified in terms of their gain, i.e., the slope between their duration and amplitude in the speed profile. Submovement gain decreased with decreasing movement frequency and increasing target size. The results were interpreted to imply that submovement gain is related to observed tracking errors and that those tracking errors are expressed in units of target size. We conclude that impedance and submovement gain modulation contribute additively to tracking accuracy.

The Bird Community Resilience Index: a novel remote sensing-based biodiversity variable for quantifying ecological integrity

Science.gov (United States)

Michel, N. L.; Wilsey, C.; Burkhalter, C.; Trusty, B.; Langham, G.

2017-12-01

Scalable indicators of biodiversity change are critical to reporting overall progress towards national and global targets for biodiversity conservation (e.g. Aichi Targets) and sustainable development (SDGs). These essential biodiversity variables capitalize on new remote sensing technologies and growth of community science participation. Here we present a novel biodiversity metric quantifying resilience of bird communities and, by extension, of their associated ecological communities. This metric adds breadth to the community composition class of essential biodiversity variables that track trends in condition and vulnerability of ecological communities. We developed this index for use with North American grassland birds, a guild that has experienced stronger population declines than any other avian guild, in order to evaluate gains from the implementation of best management practices on private lands. The Bird Community Resilience Index was designed to incorporate the full suite of species-specific responses to management actions, and be flexible enough to work across broad climatic, land cover, and bird community gradients (i.e., grasslands from northern Mexico through Canada). The Bird Community Resilience Index consists of four components: density estimates of grassland and arid land birds; weighting based on conservation need; a functional diversity metric to incorporate resiliency of bird communities and their ecosystems; and a standardized scoring system to control for interannual variation caused by extrinsic factors (e.g., climate). We present an analysis of bird community resilience across ranches in the Northern Great Plains region of the United States. As predicted, Bird Community Resilience was higher in lands implementing best management practices than elsewhere. While developed for grassland birds, this metric holds great potential for use as an Essential Biodiversity Variable for community composition in a variety of habitat.

Voluntary eye movements direct attention on the mental number space.

Science.gov (United States)

Ranzini, Mariagrazia; Lisi, Matteo; Zorzi, Marco

2016-05-01

Growing evidence suggests that orienting visual attention in space can influence the processing of numerical magnitude, with leftward orienting speeding up the processing of small numbers relative to larger ones and the converse for rightward orienting. The manipulation of eye movements is a convenient way to direct visuospatial attention, but several aspects of the complex relationship between eye movements, attention orienting and number processing remain unexplored. In a previous study, we observed that inducing involuntary, reflexive eye movements by means of optokinetic stimulation affected number processing only when numerical magnitude was task relevant (i.e., during magnitude comparison, but not during parity judgment; Ranzini et al., in J Cogn Psychol 27, 459-470, (2015). Here, we investigated whether processing of task-irrelevant numerical magnitude can be modulated by voluntary eye movements, and whether the type of eye movements (smooth pursuit vs. saccades) would influence this interaction. Participants tracked with their gaze a dot while listening to a digit. The numerical task was to indicate whether the digit was odd or even through non-spatial, verbal responses. The dot could move leftward or rightward either continuously, allowing tracking by smooth pursuit eye movements, or in discrete steps across a series of adjacent locations, triggering a sequence of saccades. Both smooth pursuit and saccadic eye movements similarly affected number processing and modulated response times for large numbers as a function of direction of motion. These findings suggest that voluntary eye movements redirect attention in mental number space and highlight that eye movements should play a key factor in the investigation of number-space interactions.

Terrestrial laser scanning point clouds time series for the monitoring of slope movements: displacement measurement using image correlation and 3D feature tracking

Science.gov (United States)

Bornemann, Pierrick; Jean-Philippe, Malet; André, Stumpf; Anne, Puissant; Julien, Travelletti

2016-04-01

Dense multi-temporal point clouds acquired with terrestrial laser scanning (TLS) have proved useful for the study of structure and kinematics of slope movements. Most of the existing deformation analysis methods rely on the use of interpolated data. Approaches that use multiscale image correlation provide a precise and robust estimation of the observed movements; however, for non-rigid motion patterns, these methods tend to underestimate all the components of the movement. Further, for rugged surface topography, interpolated data introduce a bias and a loss of information in some local places where the point cloud information is not sufficiently dense. Those limits can be overcome by using deformation analysis exploiting directly the original 3D point clouds assuming some hypotheses on the deformation (e.g. the classic ICP algorithm requires an initial guess by the user of the expected displacement patterns). The objective of this work is therefore to propose a deformation analysis method applied to a series of 20 3D point clouds covering the period October 2007 - October 2015 at the Super-Sauze landslide (South East French Alps). The dense point clouds have been acquired with a terrestrial long-range Optech ILRIS-3D laser scanning device from the same base station. The time series are analyzed using two approaches: 1) a method of correlation of gradient images, and 2) a method of feature tracking in the raw 3D point clouds. The estimated surface displacements are then compared with GNSS surveys on reference targets. Preliminary results tend to show that the image correlation method provides a good estimation of the displacement fields at first order, but shows limitations such as the inability to track some deformation patterns, and the use of a perspective projection that does not maintain original angles and distances in the correlated images. Results obtained with 3D point clouds comparison algorithms (C2C, ICP, M3C2) bring additional information on the

The effect of tumor location and respiratory function on tumor movement estimated by real-time tracking radiotherapy (RTRT) system

International Nuclear Information System (INIS)

Onimaru, Rikiya; Shirato, Hiroki; Fujino, Masaharu; Suzuki, Keishiro; Yamazaki, Kouichi; Nishimura, Masaharu; Dosaka-Akita, Hirotoshi; Miyasaka, Kazuo

2005-01-01

Purpose: The effects of tumor location and pulmonary function on the motion of fiducial markers near lung tumors were evaluated to deduce simple guidelines for determining the internal margin in radiotherapy without fiducial markers. Methods and Materials: Pooled data collected by a real-time tumor-tracking radiotherapy system on 42 markers in 39 patients were analyzed. The pulmonary functions of all patients were assessed before radiotherapy. Using chest X-ray film, the position of the marker was expressed relative to the geometry of the unilateral lung. Posterior location meant the area of the posterior half of the lung in a lateral chest X-ray film, and caudal location meant the caudal half of the chest X-ray film; these categories were determined by measuring the distance between the marker and anatomic landmarks, including the apex, costophrenic angle, midline of spinal canal, lateral, anterior, and posterior boundary of the lung. Results: Before the radiotherapy, 18 patients had obstructive respiratory dysfunction (ratio of forced expiratory volume in 1 s to forced vital capacity [FEV 1.0 /FVC] 1.0 /FVC and %VC were 97.0% and 66.5%, respectively. Median tumor movements in the x (left-right), y (anteroposterior), and z (craniocaudal) directions were 1.1 mm, 2.3 mm, and 5.4 mm, respectively. There was no significant correlation between respiratory function and magnitude of marker movement in any direction. Median marker movement in the z direction was 2.6 mm for the cranial location and 11.8 mm for the caudal location, respectively (p < 0.001). Median movement in the z direction was 11.8 mm for posterior location and 3.4 mm for anterior location, respectively (p < 0.01). Conclusions: Simple measurement of the relative location on plain chest X-ray film was related, but respiratory function test was not related, to the craniocaudal amplitude of the motion of the fiducial marker near lung tumors

Recognition of Repetitive Movement Patterns—The Case of Football Analysis

Directory of Open Access Journals (Sweden)

Udo Feuerhake

2016-11-01

Full Text Available Analyzing sports like football is interesting not only for the sports team itself, but also for the public and the media. Both have recognized that using more detailed analyses of the teams’ behavior increases their attractiveness and also their performance. For this reason, the games and the individual players are recorded using specially developed tracking systems. The tracking solution usually comes with elementary analysis software allowing for basic statistical information extraction. Going beyond these simple statistics is a challenging task. However, it is worthwhile when it provides a better view into the tactics of team or the typical movements of an individual player. In this paper an approach for the recognition of movement patterns as an advanced analysis method is presented, which uses the players’ trajectories as input data. Besides individual movement patterns it is also able to detect patterns in relation to group movements. A detailed description is followed by a discussion of the approach, where different experiments on real trajectory datasets, even from other contexts than football, show the method’s benefits and features.

1st Workshop on Eye Tracking and Visualization

CERN Document Server

Chuang, Lewis; Fisher, Brian; Schmidt, Albrecht; Weiskopf, Daniel

2017-01-01

This book discusses research, methods, and recent developments in the interdisciplinary field that spans research in visualization, eye tracking, human-computer interaction, and psychology. It presents extended versions of papers from the First Workshop on Eye Tracking and Visualization (ETVIS), which was organized as a workshop of the IEEE VIS Conference 2015. Topics include visualization and visual analytics of eye-tracking data, metrics and cognitive models, eye-tracking experiments in the context of visualization interfaces, and eye tracking in 3D and immersive environments. The extended ETVIS papers are complemented by a chapter offering an overview of visualization approaches for analyzing eye-tracking data and a chapter that discusses electrooculography (EOG) as an alternative of acquiring information about eye movements. Covering scientific visualization, information visualization, and visual analytics, this book is a valuable resource for eye-tracking researchers within the visualization community.

Birds and music

Directory of Open Access Journals (Sweden)

L Amini

2009-03-01

Through research in old mythological narrations, and literary texts, one could assume an intrinsic relationship between music and such sweet-singing mythological birds as phoenix, sphinx, Song-song, holy birds like Kership-tah, and other birds including swan and ring dove.

Tracking the movement and colonization of biocontrol agent Bacillus subtilis using radiolabelling and tracer techniques

International Nuclear Information System (INIS)

Kavitha, P.G.; Jonathan, E.I.; Nakkeeran, S.

2017-01-01

Bacillus subtilis, an endophytic bacteria that lives inside the plant system is viewed as a potential source of novel genes with antimicrobial activity. B. subtilis strain Bs5 isolated from noni was found to be antagonistic to root knot nematode, Meloidogyne incognitainvitro. The endophytic nature of the bacteria was ascertained by labeling the bacteria with radioactive 32 P and introduced in to the plant system. Autoradiograph of young noni seedlings was developed 28 days after exposure period in the X-ray film. The work was carried out in the Radioisotope Laboratory, Department of Soil Science and Agricultural Chemistry, Tamil Nadu Agricultural University, Coimbatore. Autoradiography indicated a difference in intensity of darkening of photographic emulsion. A closer scrutiny of the autoradiograph showed intensity of the film darkening to be accentuated in the top leaves. It revealed that the radio labelled bacteria effectively translocated from root to shoot and colonized the stem, mid ribs and actively growing regions. From the study it becomes evident that the radio labelling and tracer analysis is an effective tool for tracking the movement and colonization of endophytic bacteria which are potential candidates for combating plant pathogens including plant parasitic nematodes. (author)

Influenza a virus migration and persistence in North American wild birds.

Directory of Open Access Journals (Sweden)

Justin Bahl

Full Text Available Wild birds have been implicated in the emergence of human and livestock influenza. The successful prediction of viral spread and disease emergence, as well as formulation of preparedness plans have been hampered by a critical lack of knowledge of viral movements between different host populations. The patterns of viral spread and subsequent risk posed by wild bird viruses therefore remain unpredictable. Here we analyze genomic data, including 287 newly sequenced avian influenza A virus (AIV samples isolated over a 34-year period of continuous systematic surveillance of North American migratory birds. We use a Bayesian statistical framework to test hypotheses of viral migration, population structure and patterns of genetic reassortment. Our results reveal that despite the high prevalence of Charadriiformes infected in Delaware Bay this host population does not appear to significantly contribute to the North American AIV diversity sampled in Anseriformes. In contrast, influenza viruses sampled from Anseriformes in Alberta are representative of the AIV diversity circulating in North American Anseriformes. While AIV may be restricted to specific migratory flyways over short time frames, our large-scale analysis showed that the long-term persistence of AIV was independent of bird flyways with migration between populations throughout North America. Analysis of long-term surveillance data provides vital insights to develop appropriately informed predictive models critical for pandemic preparedness and livestock protection.

Person and gesture tracking with smart stereo cameras

Science.gov (United States)

Gordon, Gaile; Chen, Xiangrong; Buck, Ron

2008-02-01

Physical security increasingly involves sophisticated, real-time visual tracking of a person's location inside a given environment, often in conjunction with biometrics and other security-related technologies. However, demanding real-world conditions like crowded rooms, changes in lighting and physical obstructions have proved incredibly challenging for 2D computer vision technology. In contrast, 3D imaging technology is not affected by constant changes in lighting and apparent color, and thus allows tracking accuracy to be maintained in dynamically lit environments. In addition, person tracking with a 3D stereo camera can provide the location and movement of each individual very precisely, even in a very crowded environment. 3D vision only requires that the subject be partially visible to a single stereo camera to be correctly tracked; multiple cameras are used to extend the system's operational footprint, and to contend with heavy occlusion. A successful person tracking system, must not only perform visual analysis robustly, but also be small, cheap and consume relatively little power. The TYZX Embedded 3D Vision systems are perfectly suited to provide the low power, small footprint, and low cost points required by these types of volume applications. Several security-focused organizations, including the U.S Government, have deployed TYZX 3D stereo vision systems in security applications. 3D image data is also advantageous in the related application area of gesture tracking. Visual (uninstrumented) tracking of natural hand gestures and movement provides new opportunities for interactive control including: video gaming, location based entertainment, and interactive displays. 2D images have been used to extract the location of hands within a plane, but 3D hand location enables a much broader range of interactive applications. In this paper, we provide some background on the TYZX smart stereo cameras platform, describe the person tracking and gesture tracking systems

A simultaneous localization and tracking method for a worm tracking system

Directory of Open Access Journals (Sweden)

Kowalski Mateusz

2014-09-01

Full Text Available The idea of worm tracking refers to the path analysis of Caenorhabditis elegans nematodes and is an important tool in neurobiology which helps to describe their behavior. Knowledge about nematode behavior can be applied as a model to study the physiological addiction process or other nervous system processes in animals and humans. Tracking is performed by using a special manipulator positioning a microscope with a camera over a dish with an observed individual. In the paper, the accuracy of a nematode’s trajectory reconstruction is investigated. Special attention is paid to analyzing errors that occurred during the microscope displacements. Two sources of errors in the trajectory reconstruction are shown. One is due to the difficulty in accurately measuring the microscope shift, the other is due to a nematode displacement during the microscope movement. A new method that increases path reconstruction accuracy based only on the registered sequence of images is proposed. The method Simultaneously Localizes And Tracks (SLAT the nematodes, and is robust to the positioning system displacement errors. The proposed method predicts the nematode position by using NonParametric Regression (NPR. In addition, two other methods of the SLAT problem are implemented to evaluate the NPR method. The first consists in ignoring the nematode displacement during microscope movement, and the second is based on a Kalman filter. The results suggest that the SLAT method based on nonparametric regression gives the most promising results and decreases the error of trajectory reconstruction by 25% compared with reconstruction based on data from the positioning system

Respiration-induced movement correlation for synchronous noninvasive renal cancer surgery.

Science.gov (United States)

Abhilash, Rakkunedeth H; Chauhan, Sunita

2012-07-01

Noninvasive surgery (NIS), such as high-intensity focused ultrasound (HIFU)-based ablation or radiosurgery, is used for treating tumors and cancers in various parts of the body. The soft tissue targets (usually organs) deform and move as a result of physiological processes such as respiration. Moreover, other deformations induced during surgery by changes in patient position, changes in physical properties caused by repeated exposures and uncertainties resulting from cavitation also occur. In this paper, we present a correlation-based movement prediction technique to address respiration-induced movement of the urological organs while targeting through extracorporeal trans-abdominal route access. Among other organs, kidneys are worst affected during respiratory cycles, with significant three-dimensional displacements observed on the order of 20 mm. Remote access to renal targets such as renal carcinomas and cysts during noninvasive surgery, therefore, requires a tightly controlled real-time motion tracking and quantitative estimate for compensation routine to synchronize the energy source(s) for precise energy delivery to the intended regions. The correlation model finds a mapping between the movement patterns of external skin markers placed on the abdominal access window and the internal movement of the targeted kidney. The coarse estimate of position is then fine-tuned using the Adaptive Neuro-Fuzzy Inference System (ANFIS), thereby achieving a nonlinear mapping. The technical issues involved in this tracking scheme are threefold: the model must have sufficient accuracy in mapping the movement pattern; there must be an image-based tracking scheme to provide the organ position within allowable system latency; and the processing delay resulting from modeling and tracking must be within the achievable prediction horizon to accommodate the latency in the therapeutic delivery system. The concept was tested on ultrasound image sequences collected from 20 healthy

Lateralization of the posterior parietal cortex for internal monitoring of self- versus externally generated movements.

Science.gov (United States)

Ogawa, Kenji; Inui, Toshio

2007-11-01

Internal monitoring or state estimation of movements is essential for human motor control to compensate for inherent delays and noise in sensorimotor loops. Two types of internal estimation of movements exist: self-generated movements, and externally generated movements. We used functional magnetic resonance imaging to investigate differences in brain activity for internal monitoring of self- versus externally generated movements during visual occlusion. Participants tracked a sinusoidally moving target with a mouse cursor. On some trials, vision of either target (externally generated) or cursor (self-generated) movement was transiently occluded, during which subjects continued tracking by estimating current position of either the invisible target or cursor on screen. Analysis revealed that both occlusion conditions were associated with increased activity in the presupplementary motor area and decreased activity in the right lateral occipital cortex compared to a control condition with no occlusion. Moreover, the right and left posterior parietal cortex (PPC) showed greater activation during occlusion of target and cursor movements, respectively. This study suggests lateralization of the PPC for internal monitoring of internally versus externally generated movements, fully consistent with previously reported clinical findings.

Bird populations on the Island of Tinian: persistence despite wholesale loss of native forests

Science.gov (United States)

Camp, Richard J.; Amidon, Frederick A.; Marshall, Ann P.; Pratt, Thane K.

2012-01-01

Bird habitat on the island of Tinian, Mariana Islands, has been substantially altered, and only around 5% of the island has native forest today. The modern bird fauna is likely to be a subset of the original avifauna where only species tolerant to native forest loss and human disturbance have survived. Avian surveys were conducted on the island in 2008 by the U.S. Fish and Wildlife Service to provide current densities and abundances of the remaining species, and assess population trends using data collected from previous surveys. During the three surveys (1982, 1996, and 2008), 18 species were detected, and abundances and trends were assessed for 11 species. Five of the nine native species and one alien bird have increased since 1982. Three native birds—Mariana Fruit-Dove (Ptilinopusroseicapilla), Micronesian Honeyeater (Myzomela rubratra), and Tinian Monarch (Monarcha takatsukasae)—have decreased since 1982. Trends for the remaining two birds (one native and one alien) were considered relatively stable. Only five birds, including the Tinian Monarch, showed significant differences among regions of Tinian by year. Increased development on Tinian may result in increases in habitat clearing and expansion of human-dominated habitats, and declines in some bird populations would likely continue or be exacerbated with these actions. Expanded development activities on Tinian would also mean increased cargo movement between Guam and Tinian, elevating the probability of transporting the Brown Tree Snake (Boiga irregularis) to Tinian, which would lead to precipitous decreases and extinctions.

Tracking a Movement: U.S. Milestones in Suicide Prevention

Science.gov (United States)

Spencer-Thomas, Sally; Jahn, Danielle R.

2012-01-01

Suicidology and suicide prevention are relatively new fields of study in the United States, but they have made significant progress since their beginnings. This study aimed to identify the most impactful theories in the history of science and suicidology and the most impactful events in the suicide prevention movement. These theories and events…

Force-field compensation in a manual tracking task.

Directory of Open Access Journals (Sweden)

Valentina Squeri

2010-06-01

Full Text Available This study addresses force/movement control in a dynamic "hybrid" task: the master sub-task is continuous manual tracking of a target moving along an eight-shaped Lissajous figure, with the tracking error as the primary performance index; the slave sub-task is compensation of a disturbing curl viscous field, compatibly with the primary performance index. The two sub-tasks are correlated because the lateral force the subject must exert on the eight-shape must be proportional to the longitudinal movement speed in order to perform a good tracking. The results confirm that visuo-manual tracking is characterized by an intermittent control mechanism, in agreement with previous work; the novel finding is that the overall control patterns are not altered by the presence of a large deviating force field, if compared with the undisturbed condition. It is also found that the control of interaction-forces is achieved by a combination of arm stiffness properties and direct force control, as suggested by the systematic lateral deviation of the trajectories from the nominal path and the comparison between perturbed trials and catch trials. The coordination of the two sub-tasks is quickly learnt after the activation of the deviating force field and is achieved by a combination of force and the stiffness components (about 80% vs. 20%, which is a function of the implicit accuracy of the tracking task.

Interjoint coordination of the lower extremities in short-track speed skating.

Science.gov (United States)

Khuyagbaatar, Batbayar; Purevsuren, Tserenchimed; Park, Won Man; Kim, Kyungsoo; Kim, Yoon Hyuk

2017-10-01

In short-track speed skating, the three-dimensional kinematics of the lower extremities during the whole skating cycle have not been studied. Kinematic parameters of the lower extremities during skating are presented as joint angles versus time. However, the angle-time presentation is not sufficient to describe the relationship between multi-joint movement patterns. Thus, angle-angle presentations were developed and used to describe interjoint coordination in sport activities. In this study, 15 professional male skaters' full body motion data were recorded using a wearable motion capture system during short-track speed skating. We investigated the three-dimensional kinematics of the lower extremities and then established the interjoint coordination between hip-knee and knee-ankle for both legs during the whole skating cycle. The results demonstrate the relationship between multi-joint movements during different phases of short-track speed skating. This study provides fundamentals of the movement mechanism of the lower extremities that can be integrated with physiotherapy to improve skating posture and prevent injuries from repetitive stress since physiological characteristics play an important role in skating performance.

Railway Track Allocation: Models and Methods

DEFF Research Database (Denmark)

Lusby, Richard Martin; Larsen, Jesper; Ehrgott, Matthias

2011-01-01

Efficiently coordinating the movement of trains on a railway network is a central part of the planning process for a railway company. This paper reviews models and methods that have been proposed in the literature to assist planners in finding train routes. Since the problem of routing trains......, and train routing problems, group them by railway network type, and discuss track allocation from a strategic, tactical, and operational level....... on a railway network entails allocating the track capacity of the network (or part thereof) over time in a conflict-free manner, all studies that model railway track allocation in some capacity are considered relevant. We hence survey work on the train timetabling, train dispatching, train platforming...

Railway Track Allocation: Models and Methods

DEFF Research Database (Denmark)

Lusby, Richard Martin; Larsen, Jesper; Ehrgott, Matthias

Eciently coordinating the movement of trains on a railway network is a central part of the planning process for a railway company. This paper reviews models and methods that have been proposed in the literature to assist planners in nding train routes. Since the problem of routing trains......, and train routing problems, group them by railway network type, and discuss track allocation from a strategic, tactical, and operational level....... on a railway network entails allocating the track capacity of the network (or part thereof) over time in a con ict-free manner, all studies that model railway track allocation in some capacity are considered relevant. We hence survey work on the train timetabling, train dispatching, train platforming...

76 FR 32224 - Migratory Birds; Take of Migratory Birds by the Armed Forces

Science.gov (United States)

2011-06-03

... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service Migratory Birds; Take of Migratory Birds by... Forces to incidentally take migratory birds during approved military readiness activities without violating the Migratory Bird Treaty Act (MBTA). The Authorization Act provided this interim authority to...

Quantification of bird-to-bird and bird-to-human infections during 2013 novel H7N9 avian influenza outbreak in China.

Science.gov (United States)

Hsieh, Ying-Hen; Wu, Jianhong; Fang, Jian; Yang, Yong; Lou, Jie

2014-01-01

From February to May, 2013, 132 human avian influenza H7N9 cases were identified in China resulting in 37 deaths. We developed a novel, simple and effective compartmental modeling framework for transmissions among (wild and domestic) birds as well as from birds to human, to infer important epidemiological quantifiers, such as basic reproduction number for bird epidemic, bird-to-human infection rate and turning points of the epidemics, for the epidemic via human H7N9 case onset data and to acquire useful information regarding the bird-to-human transmission dynamics. Estimated basic reproduction number for infections among birds is 4.10 and the mean daily number of human infections per infected bird is 3.16*10-5 [3.08*10-5, 3.23*10-5]. The turning point of 2013 H7N9 epidemic is pinpointed at April 16 for bird infections and at April 9 for bird-to-human transmissions. Our result reveals very low level of bird-to-human infections, thus indicating minimal risk of widespread bird-to-human infections of H7N9 virus during the outbreak. Moreover, the turning point of the human epidemic, pinpointed at shortly after the implementation of full-scale control and intervention measures initiated in early April, further highlights the impact of timely actions on ending the outbreak. This is the first study where both the bird and human components of an avian influenza epidemic can be quantified using only the human case data.

Environmental drivers of harbour porpoise fine‑scale movements

DEFF Research Database (Denmark)

van Beest, Floris; Teilmann, Jonas; Dietz, Rune

2018-01-01

Quantifying intraspecific variation in movement behaviour of marine predators and the underlying environmental drivers is important to inform conservation management of protected species. Here, we provide the first empirical data on fine-scale movements of free-ranging harbour porpoises (Phocoena...... of various static and dynamic environmental conditions on the movement characteristics: speed, turning angle, dive duration, dive depth, dive wiggliness (a proxy for prey chasing behaviour), and post-dive duration. Despite substantial individual differences in horizontal and vertical movement patterns, we...... found that all the tracked porpoises responded similar to variation in environmental conditions and displayed movements that indicate a higher likelihood of foraging behaviour in shallower and more saline waters. Our study contributes to the identification of important feeding areas for porpoises...

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: South Florida: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for diving birds, gulls, terns, passerine birds, pelagic birds, raptors, shorebirds, wading birds, and...

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Central California: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for alcids, diving birds, gulls, terns, passerine birds, pelagic birds, raptors, shorebirds, wading birds,...

M-Track: A New Software for Automated Detection of Grooming Trajectories in Mice.

Directory of Open Access Journals (Sweden)

Sheldon L Reeves

2016-09-01

Full Text Available Grooming is a complex and robust innate behavior, commonly performed by most vertebrate species. In mice, grooming consists of a series of stereotyped patterned strokes, performed along the rostro-caudal axis of the body. The frequency and duration of each grooming episode is sensitive to changes in stress levels, social interactions and pharmacological manipulations, and is therefore used in behavioral studies to gain insights into the function of brain regions that control movement execution and anxiety. Traditional approaches to analyze grooming rely on manually scoring the time of onset and duration of each grooming episode, and are often performed on grooming episodes triggered by stress exposure, which may not be entirely representative of spontaneous grooming in freely-behaving mice. This type of analysis is time-consuming and provides limited information about finer aspects of grooming behaviors, which are important to understand movement stereotypy and bilateral coordination in mice. Currently available commercial and freeware video-tracking software allow automated tracking of the whole body of a mouse or of its head and tail, not of individual forepaws. Here we describe a simple experimental set-up and a novel open-source code, named M-Track, for simultaneously tracking the movement of individual forepaws during spontaneous grooming in multiple freely-behaving mice. This toolbox provides a simple platform to perform trajectory analysis of forepaw movement during distinct grooming episodes. By using M-track we show that, in C57BL/6 wild type mice, the speed and bilateral coordination of the left and right forepaws remain unaltered during the execution of distinct grooming episodes. Stress exposure induces a profound increase in the length of the forepaw grooming trajectories. M-Track provides a valuable and user-friendly interface to streamline the analysis of spontaneous grooming in biomedical research studies.

M-Track: A New Software for Automated Detection of Grooming Trajectories in Mice.

Science.gov (United States)

Reeves, Sheldon L; Fleming, Kelsey E; Zhang, Lin; Scimemi, Annalisa

2016-09-01

Grooming is a complex and robust innate behavior, commonly performed by most vertebrate species. In mice, grooming consists of a series of stereotyped patterned strokes, performed along the rostro-caudal axis of the body. The frequency and duration of each grooming episode is sensitive to changes in stress levels, social interactions and pharmacological manipulations, and is therefore used in behavioral studies to gain insights into the function of brain regions that control movement execution and anxiety. Traditional approaches to analyze grooming rely on manually scoring the time of onset and duration of each grooming episode, and are often performed on grooming episodes triggered by stress exposure, which may not be entirely representative of spontaneous grooming in freely-behaving mice. This type of analysis is time-consuming and provides limited information about finer aspects of grooming behaviors, which are important to understand movement stereotypy and bilateral coordination in mice. Currently available commercial and freeware video-tracking software allow automated tracking of the whole body of a mouse or of its head and tail, not of individual forepaws. Here we describe a simple experimental set-up and a novel open-source code, named M-Track, for simultaneously tracking the movement of individual forepaws during spontaneous grooming in multiple freely-behaving mice. This toolbox provides a simple platform to perform trajectory analysis of forepaw movement during distinct grooming episodes. By using M-track we show that, in C57BL/6 wild type mice, the speed and bilateral coordination of the left and right forepaws remain unaltered during the execution of distinct grooming episodes. Stress exposure induces a profound increase in the length of the forepaw grooming trajectories. M-Track provides a valuable and user-friendly interface to streamline the analysis of spontaneous grooming in biomedical research studies.

Screamy Bird

DEFF Research Database (Denmark)

Tarby, Sara; Cermak, Daniel

2016-01-01

Sara Tarby, Daniel Cermak-Sassenrath. Screamy Bird. Digital game. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016.......Sara Tarby, Daniel Cermak-Sassenrath. Screamy Bird. Digital game. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016....

Tracked Robot with Blade Arms to Enhance Crawling Capability

OpenAIRE

Jhu-Wei Ji; Fa-Shian Chang; Lih-Tyng Hwang; Chih-Feng Liu; Jeng-Nan Lee; Shun-Min Wang; Kai-Yi Cho

2016-01-01

This paper presents a tracked robot with blade arms powered to assist movement in difficult environments. As a result, the tracked robot is able to pass a ramp or climb stairs. The main feature is a pair of blade arms on both sides of the vehicle body working in collaboration with previously validated transformable track system. When the robot encounters an obstacle in a terrain, it enlists the blade arms with power to overcome the obstacle. In disaster areas, there usually will be terrains t...

Online variational Bayesian filtering-based mobile target tracking in wireless sensor networks.

Science.gov (United States)

Zhou, Bingpeng; Chen, Qingchun; Li, Tiffany Jing; Xiao, Pei

2014-11-11

The received signal strength (RSS)-based online tracking for a mobile node in wireless sensor networks (WSNs) is investigated in this paper. Firstly, a multi-layer dynamic Bayesian network (MDBN) is introduced to characterize the target mobility with either directional or undirected movement. In particular, it is proposed to employ the Wishart distribution to approximate the time-varying RSS measurement precision's randomness due to the target movement. It is shown that the proposed MDBN offers a more general analysis model via incorporating the underlying statistical information of both the target movement and observations, which can be utilized to improve the online tracking capability by exploiting the Bayesian statistics. Secondly, based on the MDBN model, a mean-field variational Bayesian filtering (VBF) algorithm is developed to realize the online tracking of a mobile target in the presence of nonlinear observations and time-varying RSS precision, wherein the traditional Bayesian filtering scheme cannot be directly employed. Thirdly, a joint optimization between the real-time velocity and its prior expectation is proposed to enable online velocity tracking in the proposed online tacking scheme. Finally, the associated Bayesian Cramer-Rao Lower Bound (BCRLB) analysis and numerical simulations are conducted. Our analysis unveils that, by exploiting the potential state information via the general MDBN model, the proposed VBF algorithm provides a promising solution to the online tracking of a mobile node in WSNs. In addition, it is shown that the final tracking accuracy linearly scales with its expectation when the RSS measurement precision is time-varying.

Tropical deforestation alters hummingbird movement patterns

Science.gov (United States)

Hadley, Adam S.; Betts, Matthew G.

2009-01-01

Reduced pollination success, as a function of habitat loss and fragmentation, appears to be a global phenomenon. Disruption of pollinator movement is one hypothesis put forward to explain this pattern in pollen limitation. However, the small size of pollinators makes them very difficult to track; thus, knowledge of their movements is largely speculative. Using tiny radio transmitters (0.25 g), we translocated a generalist tropical ‘trap-lining’ hummingbird, the green hermit (Phaethornis guy), across agricultural and forested landscapes to test the hypothesis that movement is influenced by patterns of deforestation. Although, we found no difference in homing times between landscape types, return paths were on average 459±144 m (±s.e.) more direct in forested than agricultural landscapes. In addition, movement paths in agricultural landscapes contained 36±4 per cent more forest than the most direct route. Our findings suggest that this species can circumvent agricultural matrix to move among forest patches. Nevertheless, it is clear that movement of even a highly mobile species is strongly influenced by landscape disturbance. Maintaining landscape connectivity with forest corridors may be important for enhancing movement, and thus in facilitating pollen transfer. PMID:19158031

Birds and Bird Habitat: What Are the Risks from Industrial Wind Turbine Exposure?

Science.gov (United States)

Sprague, Terry; Harrington, M. Elizabeth; Krogh, Carmen M. E.

2011-01-01

Bird kill rate and disruption of habitat has been reported when industrial wind turbines are introduced into migratory bird paths or other environments. While the literature could be more complete regarding the documentation of negative effects on birds and bird habitats during the planning, construction, and operation of wind power projects,…

Didactyl tracks of paravian theropods (Maniraptora from the ?Middle Jurassic of Africa.

Directory of Open Access Journals (Sweden)

Alexander Mudroch

Full Text Available BACKGROUND: A new dinosaur tracksite from ?Middle Jurassic sediments of the Irhazer Group on the plains of Agadez (Rep. Niger, northwest Africa revealed extraordinarily well preserved didactyl tracks of a digitigrade bipedal trackmaker. The distinct morphology of the pes imprints indicates a theropod trackmaker from a paravian maniraptoran closely related to birds. METHODOLOGY/PRINCIPAL FINDINGS: The early age and the morphological traits of the tracks allow for description of the new ichnotaxon Paravipus didactyloides. A total of 120 tracks are assigned to 5 individual trackways. The 'medium-sized' tracks with an average footprint length of 27.5 cm and footprint width of 23.1 cm are deeply imprinted into the track bearing sandstone. CONCLUSIONS/SIGNIFICANCE: A comparison with other didactyl tracks gives new insights into the foot morphology of advanced maniraptoran theropods and contributes to knowledge of their evolutionary history. The new ichnotaxon takes an important position in the ichnological fossil record of Gondwana and the mid-Jurassic biota worldwide, because it is among the earliest known records of paravian maniraptorans and of didactyl theropod tracks from Africa.

Incorporating temporal variation in seabird telemetry data: time variant kernel density models

Science.gov (United States)

Gilbert, Andrew; Adams, Evan M.; Anderson, Carl; Berlin, Alicia; Bowman, Timothy D.; Connelly, Emily; Gilliland, Scott; Gray, Carrie E.; Lepage, Christine; Meattey, Dustin; Montevecchi, William; Osenkowski, Jason; Savoy, Lucas; Stenhouse, Iain; Williams, Kathryn

2015-01-01

A key component of the Mid-Atlantic Baseline Studies project was tracking the individual movements of focal marine bird species (Red-throated Loon [Gavia stellata], Northern Gannet [Morus bassanus], and Surf Scoter [Melanitta perspicillata]) through the use of satellite telemetry. This element of the project was a collaborative effort with the Department of Energy (DOE), Bureau of Ocean Energy Management (BOEM), the U.S. Fish and Wildlife Service (USFWS), and Sea Duck Joint Venture (SDJV), among other organizations. Satellite telemetry is an effective and informative tool for understanding individual animal movement patterns, allowing researchers to mark an individual once, and thereafter follow the movements of the animal in space and time. Aggregating telemetry data from multiple individuals can provide information about the spatial use and temporal movements of populations. Tracking data is three dimensional, with the first two dimensions, X and Y, ordered along the third dimension, time. GIS software has many capabilities to store, analyze and visualize the location information, but little or no support for visualizing the temporal data, and tools for processing temporal data are lacking. We explored several ways of analyzing the movement patterns using the spatiotemporal data provided by satellite tags. Here, we present the results of one promising method: time-variant kernel density analysis (Keating and Cherry, 2009). The goal of this chapter is to demonstrate new methods in spatial analysis to visualize and interpret tracking data for a large number of individual birds across time in the mid-Atlantic study area and beyond. In this chapter, we placed greater emphasis on analytical methods than on the behavior and ecology of the animals tracked. For more detailed examinations of the ecology and wintering habitat use of the focal species in the midAtlantic, see Chapters 20-22.

MICROCONTROLLER BASED SOLAR-TRACKING SYSTEM AND ITS IMPLEMENTATION

Directory of Open Access Journals (Sweden)

Okan BİNGÖL

2006-02-01

Full Text Available In this paper, a new micro-controller based solar-tracking system is proposed, implemented and tested. The scheme presented here can be operated as independent of the geographical location of the site of setting up. The system checks the position of the sun and controls the movement of a solar panel so that radiation of the sun comes normally to the surface of the solar panel. The developed-tracking system tracks the sun both in the azimuth as well as in the elevation plane. PC based system monitoring facility is also included in the design.

Eye Tracking Metrics for Workload Estimation in Flight Deck Operation

Science.gov (United States)

Ellis, Kyle; Schnell, Thomas

2010-01-01

Flight decks of the future are being enhanced through improved avionics that adapt to both aircraft and operator state. Eye tracking allows for non-invasive analysis of pilot eye movements, from which a set of metrics can be derived to effectively and reliably characterize workload. This research identifies eye tracking metrics that correlate to aircraft automation conditions, and identifies the correlation of pilot workload to the same automation conditions. Saccade length was used as an indirect index of pilot workload: Pilots in the fully automated condition were observed to have on average, larger saccadic movements in contrast to the guidance and manual flight conditions. The data set itself also provides a general model of human eye movement behavior and so ostensibly visual attention distribution in the cockpit for approach to land tasks with various levels of automation, by means of the same metrics used for workload algorithm development.

An improved likelihood model for eye tracking

DEFF Research Database (Denmark)

Hammoud, Riad I.; Hansen, Dan Witzner

2007-01-01

While existing eye detection and tracking algorithms can work reasonably well in a controlled environment, they tend to perform poorly under real world imaging conditions where the lighting produces shadows and the person's eyes can be occluded by e.g. glasses or makeup. As a result, pixel clusters...... associated with the eyes tend to be grouped together with background-features. This problem occurs both for eye detection and eye tracking. Problems that especially plague eye tracking include head movement, eye blinking and light changes, all of which can cause the eyes to suddenly disappear. The usual...... approach in such cases is to abandon the tracking routine and re-initialize eye detection. Of course this may be a difficult process due to missed data problem. Accordingly, what is needed is an efficient method of reliably tracking a person's eyes between successively produced video image frames, even...

The quantified self a sociology of self-tracking

CERN Document Server

Lupton, Deborah

2016-01-01

With the advent of digital devices and software, self-tracking practices have gained new adherents and have spread into a wide array of social domains. The Quantified Self movement has emerged to promote 'self knowledge through numbers'. In this ground-breaking book, Deborah Lupton critically analyses the social, cultural and political dimensions of contemporary self-tracking and identifies the concepts of selfhood, human embodiment and the value of data that underpin them.

Sinusoidal visuomotor tracking: intermittent servo-control or coupled oscillations?

Science.gov (United States)

Russell, D M; Sternad, D

2001-12-01

In visuomotor tasks that involve accuracy demands, small directional changes in the trajectories have been taken as evidence of feedback-based error corrections. In the present study variability, or intermittency, in visuomanual tracking of sinusoidal targets was investigated. Two lines of analyses were pursued: First, the hypothesis that humans fundamentally act as intermittent servo-controllers was re-examined, probing the question of whether discontinuities in the movement trajectory directly imply intermittent control. Second, an alternative hypothesis was evaluated: that rhythmic tracking movements are generated by entrainment between the oscillations of the target and the actor, such that intermittency expresses the degree of stability. In 2 experiments, participants (N = 6 in each experiment) swung 1 of 2 different hand-held pendulums, tracking a rhythmic target that oscillated at different frequencies with a constant amplitude. In 1 line of analyses, the authors tested the intermittency hypothesis by using the typical kinematic error measures and spectral analysis. In a 2nd line, they examined relative phase and its variability, following analyses of rhythmic interlimb coordination. The results showed that visually guided corrective processes play a role, especially for slow movements. Intermittency, assessed as frequency and power components of the movement trajectory, was found to change as a function of both target frequency and the manipulandum's inertia. Support for entrainment was found in conditions in which task frequency was identical to or higher than the effector's eigenfrequency. The results suggest that it is the symmetry between task and effector that determines which behavioral regime is dominant.

A new method for discovering behavior patterns among animal movements

Science.gov (United States)

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.

Wind power and bird kills

International Nuclear Information System (INIS)

Raynolds, M.

1998-01-01

The accidental killing of birds by wind generators, and design improvements in the towers that support the turbines that might cut down on the bird killings were discussed. The first problem for the industry began in the late 1980s when the California Energy Commission reported as many as 160 birds (the majority being raptors, including the protected golden eagle) killed in one year in the vicinity of wind power plants. The key factor identified was the design of the towers as birds of prey are attracted to lattice towers as a place to hunt from. Tubular towers do not provide a place for the birds to perch, therefore they reduce the potential for bird strikes. Bird strikes also have been reported in Spain and the siting of the towers have been considered as the principal cause of the bird strikes. In view of these incidents, the wind power industry is developing standards for studying the potential of bird strikes and is continuing to study bird behaviour leading to collisions, the impact of topography, cumulative impacts and new techniques to reduce bird strikes. Despite the reported incidents, the risk of bird strikes by wind turbines, compared to other threats to birds such as pollution, oil spills, and other threats from fossil and nuclear fuels, is considered to be negligible. With continuing efforts to minimize incidents by proper design and siting, wind power can continue to grow as an environmentally sound and efficient source of energy

Wind power and bird kills

Energy Technology Data Exchange (ETDEWEB)

Raynolds, M.

1998-12-01

The accidental killing of birds by wind generators, and design improvements in the towers that support the turbines that might cut down on the bird killings were discussed. The first problem for the industry began in the late 1980s when the California Energy Commission reported as many as 160 birds (the majority being raptors, including the protected golden eagle) killed in one year in the vicinity of wind power plants. The key factor identified was the design of the towers as birds of prey are attracted to lattice towers as a place to hunt from. Tubular towers do not provide a place for the birds to perch, therefore they reduce the potential for bird strikes. Bird strikes also have been reported in Spain and the siting of the towers have been considered as the principal cause of the bird strikes. In view of these incidents, the wind power industry is developing standards for studying the potential of bird strikes and is continuing to study bird behaviour leading to collisions, the impact of topography, cumulative impacts and new techniques to reduce bird strikes. Despite the reported incidents, the risk of bird strikes by wind turbines, compared to other threats to birds such as pollution, oil spills, and other threats from fossil and nuclear fuels, is considered to be negligible. With continuing efforts to minimize incidents by proper design and siting, wind power can continue to grow as an environmentally sound and efficient source of energy.

Edge, height and visibility effects on nest predation by birds and mammals in the Brazilian cerrado

Science.gov (United States)

Dodonov, Pavel; Paneczko, Ingrid Toledo; Telles, Marina

2017-08-01

Edge influence is one of the main impacts in fragmented landscapes; yet, most of studies on edge influence have focused on high-contrast edges, and the impacts of low-contrast edges and narrow linear openings are less understood. Edge influence often affects bird nest predation, but these effects are not ubiquitous and may depend on characteristics such as nest height and visibility. We performed an experiment on nest predation in a migratory passerine, Elaenia chiriquensis (Lesser Elaenia; Passeriformes: Tyrannidae), in a savanna vegetation of the Brazilian Cerrado biome in South-Eastern Brazil. We used 89 real E. chiriquensis nests, collected during previous reproductive seasons, with two plasticine eggs in each, and randomly distributed them at two locations (edge - up to 20 m from a firebreak edge and interior - approx. 150-350 m from the edge) and two heights (low - 60-175 cm and high - 190-315 cm above ground). We also measured leaf and branch density around each nest. We performed this study on two 15-days campaigns, checking the nests every 2-3 days and removing those with predation marks. We sorted the predation marks into those made by birds, mammals, or unidentified predators, and used generalized linear models to assess the effects of location, height and leaf density on survival time and predator type. Only four nests had not been predated during the experiment; 55 nests were predated by birds, 7 by mammals, and 23 by unidentified predators. Low nests in the interior tended to have larger survival times whereas high nests at the edge tended to be more predated by birds and less predated by mammals. Thus, even a low-contrast (firebreak) edge may significantly increase nest predation, which is also affected by the nest's height, mainly due to predation by birds. These effects may be due to predator movement along the edge as well as to edge-related changes in vegetation structure. We suggest that higher-contrast edges which may also be used as movement

Landscape associations of birds during migratory stopover

Science.gov (United States)

Diehl, Robert Howard

The challenge for migratory bird conservation is habitat preservation that sustains breeding, migration, and non-breeding biological processes. In choosing an appropriately scaled conservation arena for habitat preservation, a conservative and thorough examination of stopover habitat use patterns by migrants works back from the larger scales at which such relationships may occur. Because the use of stopover habitats by migrating birds occurs at spatial scales larger than traditional field techniques can easily accommodate, I quantify these relationship using the United States system of weather surveillance radars (popularly known as NEXRAD). To provide perspective on use of this system for biologists, I first describe the technical challenges as well as some of the biological potential of these radars for ornithological research. Using data from these radars, I then examined the influence of Lake Michigan and the distribution of woodland habitat on migrant concentrations in northeastern Illinois habitats during stopover. Lake Michigan exerted less influence on migrant abundance and density than the distribution and availability of habitat for stopover. There was evidence of post-migratory movement resulting in habitats within suburban landscapes experiencing higher migrant abundance but lower migrant density than habitats within nearby urban and agricultural landscapes. Finally, in the context of hierarchy theory, I examined the influence of landscape ecological and behavioral processes on bird density during migratory stopover. Migrant abundance did not vary across landscapes that differed considerably in the amount of habitat available for stopover. As a result, smaller, more isolated patches held higher densities of birds. Spatial models of migrant habitat selection based on migrant proximity to a patch explained nearly as much variance in the number of migrants occupying patches (R2 = 0.88) as selection models based on migrant interception of patches during

76 FR 19875 - Migratory Bird Hunting; Proposed 2011-12 Migratory Game Bird Hunting Regulations (Preliminary...

Science.gov (United States)

2011-04-08

..., carriage, or export of any * * * bird, or any part, nest, or egg'' of migratory game birds can take place... 50 CFR Part 20 Migratory Bird Hunting; Proposed 2011-12 Migratory Game Bird Hunting Regulations (Preliminary) With Requests for Indian Tribal Proposals and Requests for 2013 Spring and Summer Migratory Bird...

Dating of movements along thrusts and faults in the Himalaya

International Nuclear Information System (INIS)

Saini, H.S.

1982-01-01

Radiometric dating of movements along the MCT (Vaikrita Thrust), two local but deep seated thrust and the Sumdoh Fault Zone bordering the Kinnar Kailas Granite in the Baspa and Satluj valleys, NE Himachal Himalaya, has been attempted for the first time by fission track method. Garnet and apatite fission track ages suggest the age of the latest phase of movements around 14 and 7 m.y. respectively along the MCT and Sumdoh Fault. The vertical uplift rates along them were 1.1mm/year from 14 to 7 m.y. and 0.6 mm/year from 7 m.y. to recent geologic past respectively, as against the value 0.036 mm/year during the period from 210 to 17 m.y. in the undisturbed area. (author)

Generalized Pareto for Pattern-Oriented Random Walk Modelling of Organisms' Movements.

Directory of Open Access Journals (Sweden)

Sophie Bertrand

Full Text Available How organisms move and disperse is crucial to understand how population dynamics relates to the spatial heterogeneity of the environment. Random walk (RW models are typical tools to describe movement patterns. Whether Lévy or alternative RW better describes forager movements is keenly debated. We get around this issue using the Generalized Pareto Distribution (GPD. GPD includes as specific cases Normal, exponential and power law distributions, which underlie Brownian, Poisson-like and Lévy walks respectively. Whereas previous studies typically confronted a limited set of candidate models, GPD lets the most likely RW model emerge from the data. We illustrate the wide applicability of the method using GPS-tracked seabird foraging movements and fishing vessel movements tracked by Vessel Monitoring System (VMS, both collected in the Peruvian pelagic ecosystem. The two parameters from the fitted GPD, a scale and a shape parameter, provide a synoptic characterization of the observed movement in terms of characteristic scale and diffusive property. They reveal and quantify the variability, among species and individuals, of the spatial strategies selected by predators foraging on a common prey field. The GPD parameters constitute relevant metrics for (1 providing a synthetic and pattern-oriented description of movement, (2 using top predators as ecosystem indicators and (3 studying the variability of spatial behaviour among species or among individuals with different personalities.

Generalized Pareto for Pattern-Oriented Random Walk Modelling of Organisms' Movements.

Science.gov (United States)

Bertrand, Sophie; Joo, Rocío; Fablet, Ronan

2015-01-01

How organisms move and disperse is crucial to understand how population dynamics relates to the spatial heterogeneity of the environment. Random walk (RW) models are typical tools to describe movement patterns. Whether Lévy or alternative RW better describes forager movements is keenly debated. We get around this issue using the Generalized Pareto Distribution (GPD). GPD includes as specific cases Normal, exponential and power law distributions, which underlie Brownian, Poisson-like and Lévy walks respectively. Whereas previous studies typically confronted a limited set of candidate models, GPD lets the most likely RW model emerge from the data. We illustrate the wide applicability of the method using GPS-tracked seabird foraging movements and fishing vessel movements tracked by Vessel Monitoring System (VMS), both collected in the Peruvian pelagic ecosystem. The two parameters from the fitted GPD, a scale and a shape parameter, provide a synoptic characterization of the observed movement in terms of characteristic scale and diffusive property. They reveal and quantify the variability, among species and individuals, of the spatial strategies selected by predators foraging on a common prey field. The GPD parameters constitute relevant metrics for (1) providing a synthetic and pattern-oriented description of movement, (2) using top predators as ecosystem indicators and (3) studying the variability of spatial behaviour among species or among individuals with different personalities.

Annotated Bibliography of Bird Hazards to Aircraft: Bird Strike Committee Citations 1967-1997

National Research Council Canada - National Science Library

Short, Jeffrey

1998-01-01

.... This annotated bibliography of bird hazards to aircraft, termed ABBHA, is a compilation of citations with abstracts on a wide range of related topics such as bird strike tolerance engineering, bird...

Long-term GPS tracking of ocean sunfish Mola mola offers a new direction in fish monitoring.

Directory of Open Access Journals (Sweden)

David W Sims

Full Text Available Satellite tracking of large pelagic fish provides insights on free-ranging behaviour, distributions and population structuring. Up to now, such fish have been tracked remotely using two principal methods: direct positioning of transmitters by Argos polar-orbiting satellites, and satellite relay of tag-derived light-level data for post hoc track reconstruction. Error fields associated with positions determined by these methods range from hundreds of metres to hundreds of kilometres. However, low spatial accuracy of tracks masks important details, such as foraging patterns. Here we use a fast-acquisition global positioning system (Fastloc GPS tag with remote data retrieval to track long-term movements, in near real time and position accuracy of <70 m, of the world's largest bony fish, the ocean sunfish Mola mola. Search-like movements occurred over at least three distinct spatial scales. At fine scales, sunfish spent longer in highly localised areas with faster, straighter excursions between them. These 'stopovers' during long-distance movement appear consistent with finding and exploiting food patches. This demonstrates the feasibility of GPS tagging to provide tracks of unparalleled accuracy for monitoring movements of large pelagic fish, and with nearly four times as many locations obtained by the GPS tag than by a conventional Argos transmitter. The results signal the potential of GPS-tagged pelagic fish that surface regularly to be detectors of resource 'hotspots' in the blue ocean and provides a new capability for understanding large pelagic fish behaviour and habitat use that is relevant to ocean management and species conservation.

78 FR 53217 - Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal Indian Reservations...

Science.gov (United States)

2013-08-28

..., and by what means such birds or any part, nest, or egg thereof may be taken, hunted, captured, killed... Service 50 CFR Part 20 Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal...-FXMB1231099BPP0] RIN 1018-AY87 Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal...

Thinking like a duck: fall lake use and movement patterns of juvenile ring-necked ducks before migration.

Science.gov (United States)

Roy, Charlotte L; Fieberg, John; Scharenbroich, Christopher; Herwig, Christine M

2014-01-01

The post-fledging period is one of the least studied portions of the annual cycle in waterfowl. Yet, recruitment into the breeding population requires that young birds have sufficient resources to survive this period. We used radio-telemetry and generalized estimating equations to examine support for four hypotheses regarding the drivers of landscape scale habitat use and movements made by juvenile ring-necked ducks between the pre-fledging period and departure for migration. Our response variables included the probability of movement, distances moved, and use of different lake types: brood-rearing lakes, staging lakes, and lakes with low potential for disturbance. Birds increased their use of staging areas and lakes with low potential for disturbance (i.e., without houses or boat accesses, >100 m from roads, or big lakes with areas where birds could sit undisturbed) throughout the fall, but these changes began before the start of the hunting season and their trajectory was not changed by the onset of hunting. Males and females moved similar distances and had similar probabilities of movements each week. However, females were more likely than males to use brood-rearing lakes later in the fall. Our findings suggest juvenile ring-necked ducks require different lake types throughout the fall, and managing solely for breeding habitat will be insufficient for meeting needs during the post-fledging period. Maintaining areas with low potential for disturbance and areas suitable for staging will ensure that ring-necked ducks have access to habitat throughout the fall.

Path Tortuosity and the Permeability of Roads and Trails to Wolf Movement

OpenAIRE

Jesse Whittington; Colleen Cassady St. Clair; George Mercer

2004-01-01

Few studies have examined the effects of human development on fine-scale movement behavior, yet understanding animal movement through increasingly human-dominated landscapes is essential for the persistence of many wild populations, especially wary species. In mountainous areas, roads and trails may be particularly deserving of study because they are concentrated in the valley bottoms where they can impede animal movement both across and between valleys. In this study, we tracked wolf (Canis ...

Fear and exploration in European starlings (Sturnus vulgaris: a comparison of hand-reared and wild-caught birds.

Directory of Open Access Journals (Sweden)

Gesa Feenders

2011-04-01

Full Text Available The revision of EU legislation will ban the use of wild-caught animals in scientific procedures. This change is partially predicated on the assumption that captive-rearing produces animals with reduced fearfulness. Previously, we have shown that hand-reared starlings (Sturnus vulgaris indeed exhibit reduced fear of humans compared to wild-caught conspecifics. Here, we asked whether this reduction in fear in hand-reared birds is limited to fear of humans or extends more generally to fear of novel environments and novel objects. Comparing 6-8 month old birds hand-reared in the lab with age-matched birds caught from the wild as fledged juveniles a minimum of 1 month previously, we examined the birds' initial reactions in a novel environment (a small cage and found that wild-caught starlings were faster to initiate movement compared to the hand-reared birds. We interpret this difference as evidence for greater escape motivation in the wild-caught birds. In contrast, we found no differences between hand-reared and wild-caught birds when tested in novel object tests assumed to measure neophobia and exploratory behaviour. Moreover, we found no correlations between individual bird's responses in the different tests, supporting the idea that these measure different traits (e.g. fear and exploration. In summary, our data show that developmental origin affects one measure of response to novelty in young starlings, indicative of a difference in either fear or coping style in a stressful situation. Our data contribute to a growing literature demonstrating effects of early-life experience on later behaviour in a range of species. However, since we did not find consistent evidence for reduced fearfulness in hand-reared birds, we remain agnostic about the welfare benefits of hand-rearing as a method for sourcing wild birds for behavioural and physiological research.

Age- and season-specific variation in local and long-distance movement behavior of golden eagles

Science.gov (United States)

Poessel, Sharon; Bloom, Peter H.; Braham, Melissa A.; Katzner, Todd E.

2016-01-01

Animal movements can determine the population dynamics of wildlife. We used telemetry data to provide insight into the causes and consequences of local and long-distance movements of multiple age classes of conservation-reliant golden eagles (Aquila chrysaetos) in the foothills and mountains near Tehachapi, California. We estimated size and habitat-related correlates of 324 monthly 95 % home ranges and 317 monthly 50 % core areas for 25 birds moving locally over 2.5 years. We also calculated daily, hourly, and total distances traveled for the five of these birds that engaged in long-distance movements. Mean (±SD) monthly home-range size was 253.6 ± 429.4 km2 and core-area size was 26.4 ± 49.7 km2. Consistent with expectations, space used by pre-adults increased with age and was season-dependent but, unexpectedly, was not sex-dependent. For all ages and sexes, home ranges and core areas were dominated by both forest & woodland and shrubland & grassland habitat types. When moving long distances, eagles traveled up to 1588.4 km (1-way) in a season at highly variable speeds (63.7 ± 69.0 km/day and 5.2 ± 10.4 km/h) that were dependent on time of day. Patterns of long-distance movements by eagles were determined by age, yet these movements had characteristics of more than one previously described movement category (migration, dispersal, etc.). Our results provide a context for differentiating among types of movement behaviors and their population-level consequences and, thus, have implications for management and conservation of golden eagle populations.

Does the brain use sliding variables for the control of movements?

Science.gov (United States)

Hanneton, S; Berthoz, A; Droulez, J; Slotine, J J

1997-12-01

Delays in the transmission of sensory and motor information prevent errors from being instantaneously available to the central nervous system (CNS) and can reduce the stability of a closed-loop control strategy. On the other hand, the use of a pure feedforward control (inverse dynamics) requires a perfect knowledge of the dynamic behavior of the body and of manipulated objects. Sensory feedback is essential both to accommodate unexpected errors and events and to compensate for uncertainties about the dynamics of the body. Experimental observations concerning the control of posture, gaze and limbs have shown that the CNS certainly uses a combination of closed-loop and open-loop control. Feedforward components of movement, such as eye saccades, occur intermittently and present a stereotyped kinematic profile. In visuo-manual tracking tasks, hand movements exhibit velocity peaks that occur intermittently. When a delay or a slow dynamics are inserted in the visuo-manual control loop, intermittent step-and-hold movements appear clearly in the hand trajectory. In this study, we investigated strategies used by human subjects involved in the control of a particular dynamic system. We found strong evidence for substantial nonlinearities in the commands produced. The presence of step-and-hold movements seemed to be the major source of nonlinearities in the control loop. Furthermore, the stereotyped ballistic-like kinematics of these rapid and corrective movements suggests that they were produced in an open-loop way by the CNS. We analyzed the generation of ballistic movements in the light of sliding control theory assuming that they occurred when a sliding variable exceeded a constant threshold. In this framework, a sliding variable is defined as a composite variable (a combination of the instantaneous tracking error and its temporal derivatives) that fulfills a specific stability criterion. Based on this hypothesis and on the assumption of a constant reaction time, the

Cook Inlet and Kenai Peninsula, Alaska ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for alcids, shorebirds, waterfowl, diving birds, pelagic birds, gulls and terns in Cook Inlet and Kenai Peninsula,...

Thermal evaluation of a sun tracking solar cooker

Energy Technology Data Exchange (ETDEWEB)

El-Tous, Yousif; Al-Mofleh, Anwar [Department of Electrical Engineering, Faculty of Engineering Technology, Al-Balqa' Applied University, P.O. Box 15008, Amman (Jordan); Badran, Omar. O. [Department of Mechanical Engineering, Faculty of Engineering Technology, Al-Balqa Appllied University, P.O. Box 15008, Amman (Jordan)

2012-07-01

Solar energy is one of many important types of renewable energy. Jordan is of great needs for renewable energy systems applications since it depends totally in generation of its required energy on imported oil. This study is an experimental work of tracking system developed for enhancing the solar heating using solar cooker. An electronic sun tracking device was used for rotating the solar heater with the movement of the sun. A comparison between fixed and sun tracked cooker showed that the use of sun tracking increased the heating temperature by 36% due to the increase in radiation concentration and using internal mirror reflectors. The programming method used for tracking control works efficiently in all weather conditions regardless of the presence of clouds. It can be used as backup control circuit in which relays are the essential control devices.

Testing an attachment method for solar-powered tracking devices on a long-distance migrating shorebird

NARCIS (Netherlands)

Chan, Y.-C; Brugge, M.; Tibbitts, T.L.; Dekinga, A.; Porter, R.; Klaassen, R.H.G.; Piersma, T.

2016-01-01

Small solar-powered satellite transmitters andGPS data loggers enable continuous, multi-year, and globaltracking of birds. What is lacking, however, are reliablemethods to attach these tracking devices to small migratorybirds so that (1) flight performance is not impacted and (2)tags are retained

Role of polarized G protein signaling in tracking pheromone gradients

Science.gov (United States)

McClure, Allison W.; Minakova, Maria; Dyer, Jayme M.; Zyla, Trevin R.; Elston, Timothy C.; Lew, Daniel J.

2015-01-01

Summary Yeast cells track gradients of pheromones to locate mating partners. Intuition suggests that uniform distribution of pheromone receptors over the cell surface would yield optimal gradient sensing. However, yeast cells display polarized receptors. The benefit of such polarization was unknown. During gradient tracking, cell growth is directed by a patch of polarity regulators that wanders around the cortex. Patch movement is sensitive to pheromone dose, with wandering reduced on the up-gradient side of the cell, resulting in net growth in that direction. Mathematical modeling suggests that active receptors and associated G proteins lag behind the polarity patch and act as an effective drag on patch movement. In vivo, the polarity patch is trailed by a G protein-rich domain, and this polarized distribution of G proteins is required to constrain patch wandering. Our findings explain why G protein polarization is beneficial, and illuminate a novel mechanism for gradient tracking. PMID:26609960

Motor Habits in Visuo-manual Tracking: Manifestation of an Unconscious Short-Term Motor Memory?

Directory of Open Access Journals (Sweden)

Andreas Hufschmidt

1990-01-01

Full Text Available Normal subjects were tested in short, repetitive trials of a tracking task, with an identical shape of target movement being used throughout one session. Analysis of the net error curves (pursuit minus target movement revealed that subjects regularly exhibit a remoteness effect: neighbouring trials were more similar than distant ones. The effect is demonstrated to be stronger in the absence of visual cues, and was found to be absent in a patient with complete loss of proprioception when he was performing without visual feedback as well. The results are discussed in terms of a short term memory store contributing to unconscious movement habits in tracking. This may represent part of the motor learning process working together with conscious visuo-motor control mechanisms. Its function is probably related to the acquisition of automatic movements.

A Kinect-sensor-based Tracked Robot for Exploring and Climbing Stairs

OpenAIRE

I-Hsum Li; Wei-Yen Wang; Chien-Kai Tseng

2014-01-01

This paper focuses on the stair-climbing problem for a tracked robot. The tracked robot designed in this paper has the ability to explore stairs in an unknown indoor environment, climbing up and down the stairs, keeping balance while climbing, and successfully landing on the stair platform. Intelligent algorithms are proposed to explore and align stairs, and a fuzzy controller is introduced to stabilize the tracked robot's movement during the exploration. An inexpensive Kinect depth sensor is...

14 CFR 33.76 - Bird ingestion.

Science.gov (United States)

2010-01-01

... single bird, the single largest medium bird which can enter the inlet, and the large flocking bird must...) (d) Large flocking bird. An engine test will be performed as follows: (1) Large flocking bird engine.... (4) Ingestion of a large flocking bird under the conditions prescribed in this paragraph must not...

Parametric Hidden Markov Models for Recognition and Synthesis of Movements

DEFF Research Database (Denmark)

Herzog, Dennis; Krüger, Volker; Grest, Daniel

2008-01-01

In humanoid robotics, the recognition and synthesis of parametric movements plays an extraordinary role for robot human interaction. Such a parametric movement is a movement of a particular type (semantic), for example, similar pointing movements performed at different table-top positions....... For understanding the whole meaning of a movement of a human, the recognition of its type, likewise its parameterization are important. Only both together convey the whole meaning. Vice versa, for mimicry, the synthesis of movements for the motor control of a robot needs to be parameterized, e.g., by the relative...... the applicability for online recognition based on very noisy 3D tracking data. The use of a parametric representation of movements is shown in a robot demo, where a robot removes objects from a table as demonstrated by an advisor. The synthesis for motor control is performed for arbitrary table-top positions....

Looking at vision : Eye/face/head tracking of consumers for improved marketing decisions

NARCIS (Netherlands)

Wedel, M.; Pieters, R.; Moutinho, L.; Bigné, E.; Manrai (eds.), A.K.

Against the backdrop of the rapid growth of the use eye tracking and facial recognition methodology, this chapter discusses the measurement of eye movements, facial expression of emotions, pupil dilation, eye blinks and head movements. After discussing some of the main research findings in the

Cognitive context determines dorsal premotor cortical activity during hand movement in patients after stroke.

Science.gov (United States)

Dennis, Andrea; Bosnell, Rose; Dawes, Helen; Howells, Ken; Cockburn, Janet; Kischka, Udo; Matthews, Paul; Johansen-Berg, Heidi

2011-04-01

Stroke patients often have difficulties in simultaneously performing a motor and cognitive task. Functional imaging studies have shown that movement of an affected hand after stroke is associated with increased activity in multiple cortical areas, particularly in the contralesional hemisphere. We hypothesized patients for whom executing simple movements demands greater selective attention will show greater brain activity during movement. Eight chronic stroke patients performed a behavioral interference test using a visuo-motor tracking with and without a simultaneous cognitive task. The magnitude of behavioral task decrement under cognitive motor interference (CMI) conditions was calculated for each subject. Functional MRI was used to assess brain activity in the same patients during performance of a visuo-motor tracking task alone; correlations between CMI score and movement-related brain activation were then explored. Movement-related activation in the dorsal precentral gyrus of the contralesional hemisphere correlated strongly and positively with CMI score (r(2) at peak voxel=0.92; Pstroke. The results emphasize the importance of considering cognitive context when interpreting brain activity patterns and provide a rationale for further evaluation of integrated cognitive and movement interventions for rehabilitation in stroke.

Coding gaze tracking data with chromatic gradients for VR Exposure Therapy

DEFF Research Database (Denmark)

Herbelin, Bruno; Grillon, Helena; De Heras Ciechomski, Pablo

2007-01-01

This article presents a simple and intuitive way to represent the eye-tracking data gathered during immersive virtual reality exposure therapy sessions. Eye-tracking technology is used to observe gaze movements during vir- tual reality sessions and the gaze-map chromatic gradient coding allows to...... is fully compatible with different VR exposure systems and provides clinically meaningful data....

Bird mortality related to collisions with ski–lift cables: do we estimate just the tip of the iceberg?

Directory of Open Access Journals (Sweden)

Bech, N.

2012-01-01

Full Text Available Collisions with ski–lift cables are an important cause of death for grouse species living close to alpine ski resorts. As several biases may reduce the detection probability of bird carcasses, the mortality rates related to these collisions are generally underestimated. The possibility that injured birds may continue flying for some distance after striking cables represents a major source of error, known as crippling bias. Estimating the crippling losses resulting from birds dying far from the ski–lift corridors is difficult and it is usually assessed by systematic searches of carcasses on both sides of the ski–lifts. Using molecular tracking, we were able to demonstrate that a rock ptarmigan hen flew up to 600 m after striking a ski–lift cable, a distance preventing its detection by traditional carcasses surveys. Given the difficulty in conducting systematic searches over large areas surrounding the ski–lifts, only an experiment using radio–tagged birds would allow us to estimate the real mortality rate associated with cable collision.

Robust microbubble tracking for super resolution imaging in ultrasound

DEFF Research Database (Denmark)

Hansen, Kristoffer B.; Villagómez Hoyos, Carlos Armando; Brasen, Jens Christian

2016-01-01

Currently ultrasound resolution is limited by diffraction to approximately half the wavelength of the sound wave employed. In recent years, super resolution imaging techniques have overcome the diffraction limit through the localization and tracking of a sparse set of microbubbles through...... the vasculature. However, this has only been performed on fixated tissue, limiting its clinical application. This paper proposes a technique for making super resolution images on non-fixated tissue by first compensating for tissue movement and then tracking the individual microbubbles. The experiment is performed...... on the kidney of a anesthetized Sprage-Dawley rat by infusing SonoVue at 0.1× original concentration. The algorithm demonstrated in vivo that the motion compensation was capable of removing the movement caused by the mechanical ventilator. The results shows that microbubbles were localized with a higher...

Phototropic solar tracking in sunflower plants: an integrative perspective

Science.gov (United States)

Kutschera, Ulrich; Briggs, Winslow R.

2016-01-01

Background One of the best-known plant movements, phototropic solar tracking in sunflower (Helianthus annuus), has not yet been fully characterized. Two questions are still a matter of debate. (1) Is the adaptive significance solely an optimization of photosynthesis via the exposure of the leaves to the sun? (2) Is shade avoidance involved in this process? In this study, these concepts are discussed from a historical perspective and novel insights are provided. Scope and Methods Results from the primary literature on heliotropic growth movements led to the conclusion that these responses cease before anthesis, so that the flowering heads point to the East. Based on observations on 10-week-old plants, the diurnal East–West oscillations of the upper fifth of the growing stem and leaves in relation to the position of the sun (inclusive of nocturnal re-orientation) were documented, and photon fluence rates on the leaf surfaces on clear, cloudy and rainy days were determined. In addition, the light–response curve of net CO2 assimilation was determined on the upper leaves of the same batch of plants, and evidence for the occurrence of shade-avoidance responses in growing sunflower plants is summarized. Conclusions. Only elongating, vegetative sunflower shoots and the upper leaves perform phototropic solar tracking. Photon fluence response and CO2 assimilation measurements cast doubt on the ‘photosynthesis-optimization hypothesis’ as the sole explanation for the evolution of these plant movements. We suggest that the shade-avoidance response, which maximizes light-driven CO2 assimilation, plays a major role in solar tracking populations of competing sunflower plants, and an integrative scheme of these growth movements is provided. PMID:26420201

Spatial and temporal movement dynamics of brook Salvelinus fontinalis and brown trout Salmo trutta

Science.gov (United States)

Davis, L.A.; Wagner, Tyler; Barton, Meredith L.

2015-01-01

Native eastern brook trout Salvelinus fontinalis and naturalized brown trout Salmo trutta occur sympatrically in many streams across the brook trout’s native range in the eastern United States. Understanding within- among-species variability in movement, including correlates of movement, has implications for management and conservation. We radio tracked 55 brook trout and 45 brown trout in five streams in a north-central Pennsylvania, USA watershed to quantify the movement of brook trout and brown trout during the fall and early winter to (1) evaluate the late-summer, early winter movement patterns of brook trout and brown trout, (2) determine correlates of movement and if movement patterns varied between brook trout and brown trout, and (3) evaluate genetic diversity of brook trout within and among study streams, and relate findings to telemetry-based observations of movement. Average total movement was greater for brown trout (mean ± SD = 2,924 ± 4,187 m) than for brook trout (mean ± SD = 1,769 ± 2,194 m). Although there was a large amount of among-fish variability in the movement of both species, the majority of movement coincided with the onset of the spawning season, and a threshold effect was detected between stream flow and movement: where movement increased abruptly for both species during positive flow events. Microsatellite analysis of brook trout revealed consistent findings to those found using radio-tracking, indicating a moderate to high degree of gene flow among brook trout populations. Seasonal movement patterns and the potential for relatively large movements of brook and brown trout highlight the importance of considering stream connectivity when restoring and protecting fish populations and their habitats.

Sex and age differences in site fidelity, food resource tracking, and body condition of wintering Kirtland's Warblers (Setophaga Kirtlandii) in the Bahamas

Science.gov (United States)

Joseph M. Wunderle, Jr.; Patricia K. Lebow; Jennifer D. White; Dave Currie; David N. Ewert

2014-01-01

Distribution of nonbreeding migrant birds in relation to variation in food availability has been hypothesized to result from the interaction of dominance hierarchies and variable movement responses, which together may have sex- and age-specific consequences. We predicted that site fidelity, movements, and abundance of Kirtland’s Warblers (Setophaga kirtlandii...

Birds Kept as Pets

Science.gov (United States)

... your pet’s health Visit a veterinarian who has experience with pet birds for routine check-ups to keep your bird healthy and prevent infectious diseases. If your bird becomes sick or dies within a month after purchase or adoption: Contact your veterinarian. Inform the pet ...

Comparing aerodynamic efficiency in birds and bats suggests better flight performance in birds.

Directory of Open Access Journals (Sweden)

Florian T Muijres

Full Text Available Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two measures of aerodynamic flight efficiency in two passerine bird species and two New World leaf-nosed bat species. Using time-resolved particle image velocimetry measurements of the wake of the animals flying in a wind tunnel, we derived the span efficiency, a metric for the efficiency of generating lift, and the lift-to-drag ratio, a metric for mechanical energetic flight efficiency. We show that the birds significantly outperform the bats in both metrics, which we ascribe to variation in aerodynamic function of body and wing upstroke: Bird bodies generated relatively more lift than bat bodies, resulting in a more uniform spanwise lift distribution and higher span efficiency. A likely explanation would be that the bat ears and nose leaf, associated with echolocation, disturb the flow over the body. During the upstroke, the birds retract their wings to make them aerodynamically inactive, while the membranous bat wings generate thrust and negative lift. Despite the differences in performance, the wake morphology of both birds and bats resemble the optimal wake for their respective lift-to-drag ratio regimes. This suggests that evolution has optimized performance relative to the respective conditions of birds and bats, but that maximum performance is possibly limited by phylogenetic constraints. Although ecological differences between birds and bats are subjected to many conspiring variables, the different aerodynamic flight efficiency for the bird and bat species studied here may help explain why birds typically fly faster, migrate more frequently and migrate

Comparing aerodynamic efficiency in birds and bats suggests better flight performance in birds.

Science.gov (United States)

Muijres, Florian T; Johansson, L Christoffer; Bowlin, Melissa S; Winter, York; Hedenström, Anders

2012-01-01

Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two measures of aerodynamic flight efficiency in two passerine bird species and two New World leaf-nosed bat species. Using time-resolved particle image velocimetry measurements of the wake of the animals flying in a wind tunnel, we derived the span efficiency, a metric for the efficiency of generating lift, and the lift-to-drag ratio, a metric for mechanical energetic flight efficiency. We show that the birds significantly outperform the bats in both metrics, which we ascribe to variation in aerodynamic function of body and wing upstroke: Bird bodies generated relatively more lift than bat bodies, resulting in a more uniform spanwise lift distribution and higher span efficiency. A likely explanation would be that the bat ears and nose leaf, associated with echolocation, disturb the flow over the body. During the upstroke, the birds retract their wings to make them aerodynamically inactive, while the membranous bat wings generate thrust and negative lift. Despite the differences in performance, the wake morphology of both birds and bats resemble the optimal wake for their respective lift-to-drag ratio regimes. This suggests that evolution has optimized performance relative to the respective conditions of birds and bats, but that maximum performance is possibly limited by phylogenetic constraints. Although ecological differences between birds and bats are subjected to many conspiring variables, the different aerodynamic flight efficiency for the bird and bat species studied here may help explain why birds typically fly faster, migrate more frequently and migrate longer distances

Evaluation of a video-based head motion tracking system for dedicated brain PET

Science.gov (United States)

Anishchenko, S.; Beylin, D.; Stepanov, P.; Stepanov, A.; Weinberg, I. N.; Schaeffer, S.; Zavarzin, V.; Shaposhnikov, D.; Smith, M. F.

2015-03-01

Unintentional head motion during Positron Emission Tomography (PET) data acquisition can degrade PET image quality and lead to artifacts. Poor patient compliance, head tremor, and coughing are examples of movement sources. Head motion due to patient non-compliance can be an issue with the rise of amyloid brain PET in dementia patients. To preserve PET image resolution and quantitative accuracy, head motion can be tracked and corrected in the image reconstruction algorithm. While fiducial markers can be used, a contactless approach is preferable. A video-based head motion tracking system for a dedicated portable brain PET scanner was developed. Four wide-angle cameras organized in two stereo pairs are used for capturing video of the patient's head during the PET data acquisition. Facial points are automatically tracked and used to determine the six degree of freedom head pose as a function of time. The presented work evaluated the newly designed tracking system using a head phantom and a moving American College of Radiology (ACR) phantom. The mean video-tracking error was 0.99±0.90 mm relative to the magnetic tracking device used as ground truth. Qualitative evaluation with the ACR phantom shows the advantage of the motion tracking application. The developed system is able to perform tracking with accuracy close to millimeter and can help to preserve resolution of brain PET images in presence of movements.

Integrating animal movement with habitat suitability for estimating dynamic landscape connectivity

Science.gov (United States)

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.

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Upper Coast of Texas: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for diving birds, gulls, terns, passerine birds, pelagic birds, raptors, shorebirds, wading birds,...

Range-wide latitudinal and elevational temperature gradients for the world's terrestrial birds: implications under global climate change.

Directory of Open Access Journals (Sweden)

Frank A La Sorte

Full Text Available Species' geographical distributions are tracking latitudinal and elevational surface temperature gradients under global climate change. To evaluate the opportunities to track these gradients across space, we provide a first baseline assessment of the steepness of these gradients for the world's terrestrial birds. Within the breeding ranges of 9,014 bird species, we characterized the spatial gradients in temperature along latitude and elevation for all and a subset of bird species, respectively. We summarized these temperature gradients globally for threatened and non-threatened species and determined how their steepness varied based on species' geography (range size, shape, and orientation and projected changes in temperature under climate change. Elevational temperature gradients were steepest for species in Africa, western North and South America, and central Asia and shallowest in Australasia, insular IndoMalaya, and the Neotropical lowlands. Latitudinal temperature gradients were steepest for extratropical species, especially in the Northern Hemisphere. Threatened species had shallower elevational gradients whereas latitudinal gradients differed little between threatened and non-threatened species. The strength of elevational gradients was positively correlated with projected changes in temperature. For latitudinal gradients, this relationship only held for extratropical species. The strength of latitudinal gradients was better predicted by species' geography, but primarily for extratropical species. Our findings suggest threatened species are associated with shallower elevational temperature gradients, whereas steep latitudinal gradients are most prevalent outside the tropics where fewer bird species occur year-round. Future modeling and mitigation efforts would benefit from the development of finer grain distributional data to ascertain how these gradients are structured within species' ranges, how and why these gradients vary among

Validity of an Athletic Skills Track among 6- to 12-year-old children.

Science.gov (United States)

Hoeboer, Joris; De Vries, Sanne; Krijger-Hombergen, Michiel; Wormhoudt, René; Drent, Annelies; Krabben, Kay; Savelsbergh, Geert

2016-11-01

The purpose of this study was to examine the feasibility and validity of an Athletic Skills Track (AST) to assess fundamental movement skills among 6- to 12-year-old children in a physical education setting. Four hundred sixty-three Dutch children (211 girls, 252 boys) completed three tests: the Körperkoordinationstest für Kinder (KTK) and two Athletic Skills Tracks (AST-1, AST-2). The validity of AST-1 and AST-2 was examined by correlating the time (s) needed to complete the tracks and the KTK Motor Quotient (MQ). Overall, there was a low correlation between AST-1 and the KTK MQ (r = -0.474 (P fundamental movement skills of 6- to 12-year-old children can be assessed with a quick, convenient and low-cost motor competence test in a physical education setting, i.e., an Athletic Skills Track. Future studies should further assess the reliability, discriminative ability and validity of age-specific versions of the AST.

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northern California: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for alcids, diving birds, gulls, terns, passerines, pelagic birds, raptors, shorebirds, wading birds, and...

Bird guard

Science.gov (United States)

Fairchild, Dana M [Armour, SD

2010-03-02

The bird guard provides a device to protect electrical insulators comprising a central shaft; a clamp attached to an end of the shaft to secure the device to a transmission tower; a top and bottom cover to shield transmission tower insulators; and bearings to allow the guard to rotate in order to frighten birds away from the insulators.

Avoidance behavior by prairie grouse: implications for development of wind energy.

Science.gov (United States)

Pruett, Christin L; Patten, Michael A; Wolfe, Donald H

2009-10-01

New wind-energy facilities and their associated power transmission lines and roads are being constructed at a rapid pace in the Great Plains of North America. Nevertheless, little is known about the possible negative effects these anthropogenic features might have on prairie birds, one of the most threatened groups in North America. We examined radiotelemetry tracking locations of Lesser Prairie-Chickens (Tympanuchus pallidicinctus) and Greater Prairie-Chickens (T. cupido) in two locations in Oklahoma to determine whether these birds avoided or changed movement behavior near power lines and paved highways. We tracked 463 Lesser Prairie-Chickens (15,071 tracking locations) and 216 Greater Prairie-Chickens (5,750 locations) for 7 and 3 years, respectively. Individuals of both species avoided power lines by at least 100 m and Lesser Prairie-Chickens avoided one of the two highways by 100 m. Prairie-chickens crossed power lines less often than expected if birds moved randomly (p 0.05). In addition, home ranges of Lesser Prairie-Chickens overlapped the power line less often than would be expected by chance placement of home ranges; this result was supported by kernel-density estimation of home ranges. It is likely that new power lines (and other tall structures such as wind turbines) will lead to avoidance of previously suitable habitat and will serve as barriers to movement. These two factors will likely increase fragmentation in an already fragmented landscape if wind energy development continues in prairie habitats.

Science and technology with nuclear tracks in solids

CERN Document Server

Buford-Price, P

2005-01-01

Fission track dating has greatly expanded its usefulness to geology over the last 40 years. It is central to thermochronology—the use of shortened fission tracks to decipher the thermal history, movement, and provenance of rocks. When combined with other indicators, such as zircon color and (U–Th)/He, a range of temperatures from C to C can be studied. Combining fission track analysis with cosmogenic nuclide decay rates, one can study landscape development and denudation of passive margins. Technological applications have expanded from biological filters, radon mapping, and dosimetry to the use of ion track microtechnology in microlithography, micromachining by ion track etching, microscopic field emission tips, magnetic nanowires as magnetoresistive sensors, microfluidic devices, physiology of ion channels in single cells, and so on. In nuclear and particle physics, relatively insensitive glass detectors have been almost single-handedly responsible for our knowledge of cluster radioactivity, and plastic ...

Geometry and Gesture-Based Features from Saccadic Eye-Movement as a Biometric in Radiology

Energy Technology Data Exchange (ETDEWEB)

Hammond, Tracy [Texas A& M University, College Station; Tourassi, Georgia [ORNL; Yoon, Hong-Jun [ORNL; Alamudun, Folami T. [ORNL

2017-07-01

In this study, we present a novel application of sketch gesture recognition on eye-movement for biometric identification and estimating task expertise. The study was performed for the task of mammographic screening with simultaneous viewing of four coordinated breast views as typically done in clinical practice. Eye-tracking data and diagnostic decisions collected for 100 mammographic cases (25 normal, 25 benign, 50 malignant) and 10 readers (three board certified radiologists and seven radiology residents), formed the corpus for this study. Sketch gesture recognition techniques were employed to extract geometric and gesture-based features from saccadic eye-movements. Our results show that saccadic eye-movement, characterized using sketch-based features, result in more accurate models for predicting individual identity and level of expertise than more traditional eye-tracking features.

Moving in the Anthropocene: Global reductions in terrestrial mammalian movements

Science.gov (United States)

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.

Acting without seeing: eye movements reveal visual processing without awareness.

Science.gov (United States)

Spering, Miriam; Carrasco, Marisa

2015-04-01

Visual perception and eye movements are considered to be tightly linked. Diverse fields, ranging from developmental psychology to computer science, utilize eye tracking to measure visual perception. However, this prevailing view has been challenged by recent behavioral studies. Here, we review converging evidence revealing dissociations between the contents of perceptual awareness and different types of eye movement. Such dissociations reveal situations in which eye movements are sensitive to particular visual features that fail to modulate perceptual reports. We also discuss neurophysiological, neuroimaging, and clinical studies supporting the role of subcortical pathways for visual processing without awareness. Our review links awareness to perceptual-eye movement dissociations and furthers our understanding of the brain pathways underlying vision and movement with and without awareness. Copyright © 2015 Elsevier Ltd. All rights reserved.

Do Activity Level Outcome Measures Commonly Used in Neurological Practice Assess Upper-Limb Movement Quality?

Science.gov (United States)

Demers, Marika; Levin, Mindy F

2017-07-01

Movement is described in terms of task-related end point characteristics in external space and movement quality (joint rotations in body space). Assessment of upper-limb (UL) movement quality can assist therapists in designing effective treatment approaches for retraining lost motor elements and provide more detailed measurements of UL motor improvements over time. To determine the extent to which current activity level outcome measures used in neurological practice assess UL movement quality. Outcome measures assessing arm/hand function at the International Classification of Function activity level recommended by neurological clinical practice guidelines were reviewed. Measures assessing the UL as part of a general mobility assessment, those strictly evaluating body function/structure or participation, and paediatric measures were excluded. In all, 15 activity level outcome measures were identified; 9 measures assess how movement is performed by measuring either end point characteristics or movement quality. However, except for the Reaching Performance Scale for Stroke and the Motor Evaluation Scale for Upper Extremity in Stroke Patients, these measures only account for deficits indirectly by giving a partial score if movements are slower or if the person experiences difficulties. Six outcome measures neither assess any parameters related to movement quality, nor distinguish between improvements resulting from motor compensation or recovery of desired movement strategies. Current activity measures may not distinguish recovery from compensation and adequately track changes in movement quality over time. Movement quality may be incorporated into clinical assessment using observational kinematics with or without low-cost motion tracking technology.

76 FR 59298 - Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal Indian Reservations...

Science.gov (United States)

2011-09-26

... such birds or any part, nest, or egg thereof may be taken, hunted, captured, killed, possessed, sold...-0014; 91200-1231-9BPP-L2] RIN 1018-AX34 Migratory Bird Hunting; Migratory Bird Hunting Regulations on... Service, Interior. ACTION: Final rule. SUMMARY: This rule prescribes special late-season migratory bird...

Changes in habitat use at rainforest edges through succession: A case study of understory birds in the Brazilian Amazon

Science.gov (United States)

Luke L. Powell; Gustavo Zurita; Jared D.  Wolfe; Erik I.  Johnson; Philip C  Stouffer

2015-01-01

Primary tropical rain forests are being rapidly perforated with new edges via roads, logging, and pastures, and vast areas of secondary forest accumulate following abandonment of agricultural lands. To determine how insectivorous Amazonian understory birds respond to edges between primary rain forest and three age classes of secondary forest, we radio-tracked two...

Distinct eye movement patterns enhance dynamic visual acuity

Science.gov (United States)

Palidis, Dimitrios J.; Wyder-Hodge, Pearson A.; Fooken, Jolande; Spering, Miriam

2017-01-01

Dynamic visual acuity (DVA) is the ability to resolve fine spatial detail in dynamic objects during head fixation, or in static objects during head or body rotation. This ability is important for many activities such as ball sports, and a close relation has been shown between DVA and sports expertise. DVA tasks involve eye movements, yet, it is unclear which aspects of eye movements contribute to successful performance. Here we examined the relation between DVA and the kinematics of smooth pursuit and saccadic eye movements in a cohort of 23 varsity baseball players. In a computerized dynamic-object DVA test, observers reported the location of the gap in a small Landolt-C ring moving at various speeds while eye movements were recorded. Smooth pursuit kinematics—eye latency, acceleration, velocity gain, position error—and the direction and amplitude of saccadic eye movements were linked to perceptual performance. Results reveal that distinct eye movement patterns—minimizing eye position error, tracking smoothly, and inhibiting reverse saccades—were related to dynamic visual acuity. The close link between eye movement quality and DVA performance has important implications for the development of perceptual training programs to improve DVA. PMID:28187157

Eye Movements During Everyday Behavior Predict Personality Traits.

Science.gov (United States)

Hoppe, Sabrina; Loetscher, Tobias; Morey, Stephanie A; Bulling, Andreas

2018-01-01

Besides allowing us to perceive our surroundings, eye movements are also a window into our mind and a rich source of information on who we are, how we feel, and what we do. Here we show that eye movements during an everyday task predict aspects of our personality. We tracked eye movements of 42 participants while they ran an errand on a university campus and subsequently assessed their personality traits using well-established questionnaires. Using a state-of-the-art machine learning method and a rich set of features encoding different eye movement characteristics, we were able to reliably predict four of the Big Five personality traits (neuroticism, extraversion, agreeableness, conscientiousness) as well as perceptual curiosity only from eye movements. Further analysis revealed new relations between previously neglected eye movement characteristics and personality. Our findings demonstrate a considerable influence of personality on everyday eye movement control, thereby complementing earlier studies in laboratory settings. Improving automatic recognition and interpretation of human social signals is an important endeavor, enabling innovative design of human-computer systems capable of sensing spontaneous natural user behavior to facilitate efficient interaction and personalization.

Eye Movements During Everyday Behavior Predict Personality Traits

Directory of Open Access Journals (Sweden)

Sabrina Hoppe

2018-04-01

Full Text Available Besides allowing us to perceive our surroundings, eye movements are also a window into our mind and a rich source of information on who we are, how we feel, and what we do. Here we show that eye movements during an everyday task predict aspects of our personality. We tracked eye movements of 42 participants while they ran an errand on a university campus and subsequently assessed their personality traits using well-established questionnaires. Using a state-of-the-art machine learning method and a rich set of features encoding different eye movement characteristics, we were able to reliably predict four of the Big Five personality traits (neuroticism, extraversion, agreeableness, conscientiousness as well as perceptual curiosity only from eye movements. Further analysis revealed new relations between previously neglected eye movement characteristics and personality. Our findings demonstrate a considerable influence of personality on everyday eye movement control, thereby complementing earlier studies in laboratory settings. Improving automatic recognition and interpretation of human social signals is an important endeavor, enabling innovative design of human–computer systems capable of sensing spontaneous natural user behavior to facilitate efficient interaction and personalization.

Distinct eye movement patterns enhance dynamic visual acuity.

Science.gov (United States)

Palidis, Dimitrios J; Wyder-Hodge, Pearson A; Fooken, Jolande; Spering, Miriam

2017-01-01

Dynamic visual acuity (DVA) is the ability to resolve fine spatial detail in dynamic objects during head fixation, or in static objects during head or body rotation. This ability is important for many activities such as ball sports, and a close relation has been shown between DVA and sports expertise. DVA tasks involve eye movements, yet, it is unclear which aspects of eye movements contribute to successful performance. Here we examined the relation between DVA and the kinematics of smooth pursuit and saccadic eye movements in a cohort of 23 varsity baseball players. In a computerized dynamic-object DVA test, observers reported the location of the gap in a small Landolt-C ring moving at various speeds while eye movements were recorded. Smooth pursuit kinematics-eye latency, acceleration, velocity gain, position error-and the direction and amplitude of saccadic eye movements were linked to perceptual performance. Results reveal that distinct eye movement patterns-minimizing eye position error, tracking smoothly, and inhibiting reverse saccades-were related to dynamic visual acuity. The close link between eye movement quality and DVA performance has important implications for the development of perceptual training programs to improve DVA.

Day and night feeding habitat of Red Knots in Patagonia : Profitability versus safety?

NARCIS (Netherlands)

Sitters, HP; Gonzalez, PM; Piersma, T; Baker, AJ; Price, DJ; Sitters, Humphrey P.; González, Patricia M.; Baker, Allan J.; Price, David J.

2001-01-01

By radio-tracking and recording the movements of flocks. the distribution of feeding Red Knots (Calidris canutus rufa) was studied day and night at a migration stopover site near San Antonio Oeste, Rio Negro, Argentina in March and April 1998. By day, the birds fed in dense flocks of 500-4000 on an

Hawaii ESI: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for endangered waterbirds and passerine birds, migratory shorebirds and waterfowl, gulls and terns,...

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

Science.gov (United States)

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).

78 FR 65578 - Migratory Bird Permits; Depredation Order for Migratory Birds in California

Science.gov (United States)

2013-11-01

...-0037; FF09M21200-134-FXMB1231099BPP0] RIN 1018-AY65 Migratory Bird Permits; Depredation Order for Migratory Birds in California AGENCY: Fish and Wildlife Service, Interior. ACTION: Final rule. SUMMARY: We revise the regulations that allow control of depredating birds in California. We specify the counties in...

Acting without seeing: Eye movements reveal visual processing without awareness Miriam Spering & Marisa Carrasco

OpenAIRE

Spering, Miriam; Carrasco, Marisa

2015-01-01

Visual perception and eye movements are considered to be tightly linked. Diverse fields, ranging from developmental psychology to computer science, utilize eye tracking to measure visual perception. However, this prevailing view has been challenged by recent behavioral studies. We review converging evidence revealing dissociations between the contents of perceptual awareness and different types of eye movements. Such dissociations reveal situations in which eye movements are sensitive to part...

Modeling birds on wires.

Science.gov (United States)

Aydoğdu, A; Frasca, P; D'Apice, C; Manzo, R; Thornton, J M; Gachomo, B; Wilson, T; Cheung, B; Tariq, U; Saidel, W; Piccoli, B

2017-02-21

In this paper we introduce a mathematical model to study the group dynamics of birds resting on wires. The model is agent-based and postulates attraction-repulsion forces between the interacting birds: the interactions are "topological", in the sense that they involve a given number of neighbors irrespective of their distance. The model is first mathematically analyzed and then simulated to study its main properties: we observe that the model predicts birds to be more widely spaced near the borders of each group. We compare the results from the model with experimental data, derived from the analysis of pictures of pigeons and starlings taken in New Jersey: two different image elaboration protocols allow us to establish a good agreement with the model and to quantify its main parameters. We also discuss the potential handedness of the birds, by analyzing the group organization features and the group dynamics at the arrival of new birds. Finally, we propose a more refined mathematical model that describes landing and departing birds by suitable stochastic processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

GPS-Aided Video Tracking

Directory of Open Access Journals (Sweden)

Udo Feuerhake

2015-08-01

Full Text Available Tracking moving objects is both challenging and important for a large variety of applications. Different technologies based on the global positioning system (GPS and video or radio data are used to obtain the trajectories of the observed objects. However, in some use cases, they fail to provide sufficiently accurate, complete and correct data at the same time. In this work we present an approach for fusing GPS- and video-based tracking in order to exploit their individual advantages. In this way we aim to combine the reliability of GPS tracking with the high geometric accuracy of camera detection. For the fusion of the movement data provided by the different devices we use a hidden Markov model (HMM formulation and the Viterbi algorithm to extract the most probable trajectories. In three experiments, we show that our approach is able to deal with challenging situations like occlusions or objects which are temporarily outside the monitored area. The results show the desired increase in terms of accuracy, completeness and correctness.

Use of Cognitive and Metacognitive Strategies in Online Search: An Eye-Tracking Study

Science.gov (United States)

Zhou, Mingming; Ren, Jing

2016-01-01

This study used eye-tracking technology to track students' eye movements while searching information on the web. The research question guiding this study was "Do students with different search performance levels have different visual attention distributions while searching information online? If yes, what are the patterns for high and low…

Fast and Practical Head Tracking in Brain Imaging with Time-of-Flight Camera

DEFF Research Database (Denmark)

Wilm, Jakob; Olesen, Oline Vinter; Jensen, Rasmus Ramsbøl

2013-01-01

scanners. Particularly in MRI and PET, the newest generation of TOF cameras could become a method of tracking small and large scale patient movement in a fast and user friendly way required in clinical environments. We present a novel methodology for fast tracking from TOF point clouds without the need...

Systems and methods of eye tracking calibration

DEFF Research Database (Denmark)

2014-01-01

Methods and systems to facilitate eye tracking control calibration are provided. One or more objects are displayed on a display of a device, where the one or more objects are associated with a function unrelated to a calculation of one or more calibration parameters. The one or more calibration...... parameters relate to a calibration of a calculation of gaze information of a user of the device, where the gaze information indicates where the user is looking. While the one or more objects are displayed, eye movement information associated with the user is determined, which indicates eye movement of one...... or more eye features associated with at least one eye of the user. The eye movement information is associated with a first object location of the one or more objects. The one or more calibration parameters are calculated based on the first object location being associated with the eye movement information....

Fatigue effects on tracking performance and muscle activity

NARCIS (Netherlands)

Huysmans, M.A.; Hoozemans, M.J.M.; van der Beek, A.J.; de Looze, M.P.; van Dieen, J.H.

2008-01-01

It has been suggested that fatigue affects proprioception and consequently movement accuracy, the effects of which may be counteracted by increased muscle activity. To determine the effects of fatigue on tracking performance and muscle activity in the M. extensor carpi radialis (ECR), 11 female

Arctic sea ice a major determinant in Mandt's black guillemot movement and distribution during non-breeding season

Science.gov (United States)

Divoky, G.J.; Douglas, David C.; Stenhouse, I. J.

2016-01-01

Mandt's black guillemot (Cepphus grylle mandtii) is one of the few seabirds associated in all seasons with Arctic sea ice, a habitat that is changing rapidly. Recent decreases in summer ice have reduced breeding success and colony size of this species in Arctic Alaska. Little is known about the species' movements and distribution during the nine month non-breeding period (September–May), when changes in sea ice extent and composition are also occurring and predicted to continue. To examine bird movements and the seasonal role of sea ice to non-breeding Mandt's black guillemots, we deployed and recovered (n = 45) geolocators on individuals at a breeding colony in Arctic Alaska during 2011–2015. Black guillemots moved north to the marginal ice zone (MIZ) in the Beaufort and Chukchi seas immediately after breeding, moved south to the Bering Sea during freeze-up in December, and wintered in the Bering Sea January–April. Most birds occupied the MIZ in regions averaging 30–60% sea ice concentration, with little seasonal variation. Birds regularly roosted on ice in all seasons averaging 5 h d−1, primarily at night. By using the MIZ, with its roosting opportunities and associated prey, black guillemots can remain in the Arctic during winter when littoral waters are completely covered by ice.

Movement-based interaction in camera spaces: a conceptual framework

DEFF Research Database (Denmark)

Eriksson, Eva; Hansen, Thomas Riisgaard; Lykke-Olesen, Andreas

2007-01-01

In this paper we present three concepts that address movement-based interaction using camera tracking. Based on our work with several movementbased projects we present four selected applications, and use these applications to leverage our discussion, and to describe our three main concepts space,...

Reduction in adverse effects of tracking devices on waterfowl requires better measuring and reporting

NARCIS (Netherlands)

Lameris, T.K.; Kleyheeg, Erik

2017-01-01

Since the first studies in the mid-twentieth century, lightweight electronic tracking devices have been increasingly used to study waterfowl movements. With half a century of experience and growing sample sizes, it has become clear that the attachment of a tracking device can affect a bird’s

APM_GUI: analyzing particle movement on the cell membrane and determining confinement.

Science.gov (United States)

Menchón, Silvia A; Martín, Mauricio G; Dotti, Carlos G

2012-02-20

Single-particle tracking is a powerful tool for tracking individual particles with high precision. It provides useful information that allows the study of diffusion properties as well as the dynamics of movement. Changes in particle movement behavior, such as transitions between Brownian motion and temporary confinement, can reveal interesting biophysical interactions. Although useful applications exist to determine the paths of individual particles, only a few software implementations are available to analyze these data, and these implementations are generally not user-friendly and do not have a graphical interface,. Here, we present APM_GUI (Analyzing Particle Movement), which is a MatLab-implemented application with a Graphical User Interface. This user-friendly application detects confined movement considering non-random confinement when a particle remains in a region longer than a Brownian diffusant would remain. In addition, APM_GUI exports the results, which allows users to analyze this information using software that they are familiar with. APM_GUI provides an open-source tool that quantifies diffusion coefficients and determines whether trajectories have non-random confinements. It also offers a simple and user-friendly tool that can be used by individuals without programming skills.

APM_GUI: analyzing particle movement on the cell membrane and determining confinement

Directory of Open Access Journals (Sweden)

Menchón Silvia A

2012-02-01

Full Text Available Abstract Background Single-particle tracking is a powerful tool for tracking individual particles with high precision. It provides useful information that allows the study of diffusion properties as well as the dynamics of movement. Changes in particle movement behavior, such as transitions between Brownian motion and temporary confinement, can reveal interesting biophysical interactions. Although useful applications exist to determine the paths of individual particles, only a few software implementations are available to analyze these data, and these implementations are generally not user-friendly and do not have a graphical interface,. Results Here, we present APM_GUI (Analyzing Particle Movement, which is a MatLab-implemented application with a Graphical User Interface. This user-friendly application detects confined movement considering non-random confinement when a particle remains in a region longer than a Brownian diffusant would remain. In addition, APM_GUI exports the results, which allows users to analyze this information using software that they are familiar with. Conclusions APM_GUI provides an open-source tool that quantifies diffusion coefficients and determines whether trajectories have non-random confinements. It also offers a simple and user-friendly tool that can be used by individuals without programming skills.

Emerging applications of eye-tracking technology in dermatology.

Science.gov (United States)

John, Kevin K; Jensen, Jakob D; King, Andy J; Pokharel, Manusheela; Grossman, Douglas

2018-04-06

Eye-tracking technology has been used within a multitude of disciplines to provide data linking eye movements to visual processing of various stimuli (i.e., x-rays, situational positioning, printed information, and warnings). Despite the benefits provided by eye-tracking in allowing for the identification and quantification of visual attention, the discipline of dermatology has yet to see broad application of the technology. Notwithstanding dermatologists' heavy reliance upon visual patterns and cues to discriminate between benign and atypical nevi, literature that applies eye-tracking to the study of dermatology is sparse; and literature specific to patient-initiated behaviors, such as skin self-examination (SSE), is largely non-existent. The current article provides a review of eye-tracking research in various medical fields, culminating in a discussion of current applications and advantages of eye-tracking for dermatology research. Copyright © 2018 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Soaring migratory birds avoid wind farm in the Isthmus of Tehuantepec, southern Mexico.

Science.gov (United States)

Villegas-Patraca, Rafael; Cabrera-Cruz, Sergio A; Herrera-Alsina, Leonel

2014-01-01

The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura) and Swainson's Hawks (Buteo swainsoni). We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region.

Medical Imaging for the Tracking of Micromotors.

Science.gov (United States)

Vilela, Diana; Cossío, Unai; Parmar, Jemish; Martínez-Villacorta, Angel M; Gómez-Vallejo, Vanessa; Llop, Jordi; Sánchez, Samuel

2018-02-27

Micro/nanomotors are useful tools for several biomedical applications, including targeted drug delivery and minimally invasive microsurgeries. However, major challenges such as in vivo imaging need to be addressed before they can be safely applied on a living body. Here, we show that positron emission tomography (PET), a molecular imaging technique widely used in medical imaging, can also be used to track a large population of tubular Au/PEDOT/Pt micromotors. Chemisorption of an iodine isotope onto the micromotor's Au surface rendered them detectable by PET, and we could track their movements in a tubular phantom over time frames of up to 15 min. In a second set of experiments, micromotors and the bubbles released during self-propulsion were optically tracked by video imaging and bright-field microscopy. The results from direct optical tracking agreed with those from PET tracking, demonstrating that PET is a suitable technique for the imaging of large populations of active micromotors in opaque environments, thus opening opportunities for the use of this mature imaging technology for the in vivo localization of artificial swimmers.

Movement analysis of free-grazing domestic ducks in Poyang Lake, China: A disease connection

Science.gov (United States)

Prosser, Diann J.; Palm, Eric C.; Takekawa, John Y.; Zhao, Delong; Xiao, Xiangming; Li, Peng; Liu, Ying; Newman, Scott H.

2015-01-01

Previous work suggests domestic poultry are important contributors to the emergence and transmission of highly pathogenic avian influenza throughout Asia. In Poyang Lake, China, domestic duck production cycles are synchronized with arrival and departure of thousands of migratory wild birds in the area. During these periods, high densities of juvenile domestic ducks are in close proximity to migratory wild ducks, increasing the potential for the virus to be transmitted and subsequently disseminated via migration. In this paper, we use GPS dataloggers and dynamic Brownian bridge models to describe movements and habitat use of free-grazing domestic ducks in the Poyang Lake basin and identify specific areas that may have the highest risk of H5N1 transmission between domestic and wild birds. Specifically, we determine relative use by free-grazing domestic ducks of natural wetlands, which are the most heavily used areas by migratory wild ducks, and of rice paddies, which provide habitat for resident wild ducks and lower densities of migratory wild ducks. To our knowledge, this is the first movement study on domestic ducks, and our data show potential for free-grazing domestic ducks from farms located near natural wetlands to come in contact with wild waterfowl, thereby increasing the risk for disease transmission. This study provides an example of the importance of movement ecology studies in understanding dynamics such as disease transmission on a complicated landscape.

Movement analysis of free-grazing domestic ducks in Poyang Lake, China: a disease connection.

Science.gov (United States)

Prosser, Diann J; Palm, Eric C; Takekawa, John Y; Zhao, Delong; Xiao, Xiangming; Li, Peng; Liu, Ying; Newman, Scott H

2016-01-01

Previous work suggests domestic poultry are important contributors to the emergence and transmission of highly pathogenic avian influenza throughout Asia. In Poyang Lake, China, domestic duck production cycles are synchronized with arrival and departure of thousands of migratory wild birds in the area. During these periods, high densities of juvenile domestic ducks are in close proximity to migratory wild ducks, increasing the potential for the virus to be transmitted and subsequently disseminated via migration. In this paper, we use GPS dataloggers and dynamic Brownian bridge models to describe movements and habitat use of free-grazing domestic ducks in the Poyang Lake basin and identify specific areas that may have the highest risk of H5N1 transmission between domestic and wild birds. Specifically, we determine relative use by free-grazing domestic ducks of natural wetlands, which are the most heavily used areas by migratory wild ducks, and of rice paddies, which provide habitat for resident wild ducks and lower densities of migratory wild ducks. To our knowledge, this is the first movement study on domestic ducks, and our data show potential for free-grazing domestic ducks from farms located near natural wetlands to come in contact with wild waterfowl, thereby increasing the risk for disease transmission. This study provides an example of the importance of movement ecology studies in understanding dynamics such as disease transmission on a complicated landscape.

Audubon Bird Study Program.

Science.gov (United States)

National Audubon Society, New York, NY.

Included are a student reader, "The Story of Birds," a leaders' guide, a large colored Audubon bird chart, and a separate guide for the chart. The student reader is divided into eleven sections which relate to the various physical and behavioral features of birds such as feathers, feeding habits as related to the shape of bills and feet, nests,…

A review on current knowledge and future prospects of organohalogen contaminants (OHCs) in Asian birds.

Science.gov (United States)

Abbasi, Naeem Akhtar; Malik, Riffat Naseem; Frantz, Adrien; Jaspers, Veerle Leontina Bernard

2016-01-15

The release of harmful chemicals in the Asian environment has recently increased dramatically due to rising industrial and agricultural activities. About 60% of the global human population is currently living on the Asian continent and may thus be exposed to a large range of different chemicals. Different classes of organohalogen chemicals have indeed been reported in various environmental compartments from Asia including humans and wildlife, but this issue has received less attention in birds. In this article, we reviewed the available literature on levels of legacy persistent organic pollutants (POPs) and various flame retardants (FRs) in Asian avifauna to analyze the existing pool of knowledge as well as to identify the gaps that should be addressed in future research. Furthermore, we discussed the variation in levels of organohalogens based on differences in regions, trophic level, dietary sources and migratory behaviors of species including distribution patterns in different tissues of birds. Although the mass of published literature is very low and even absent in many important regions of Asia, we deduced from the reported studies that levels of almost all classes of organohalogens (OHCs) including FRs were highest in East Asian countries such as Japan, China and South Korea, except for HCHs that were found at maximum levels in birds of South India. Concentrations (ng/g LW) of different OHCs in Asian birds ranged between birds, vicinity to sources and trans-boundary movement of pollutants were identified as key exposure routes and subsequent OHCs contamination in Asian birds. There is extreme scarcity of literature on organohalogen contamination in birds from Northern, South-eastern and west Asian countries where an industrial boom has been witnessed in the past few decades. Current scenarios suggest that levels of OHCs, particularly the FRs, are rising in birds of Asia and it would be wise to develop baseline information and to regulate the OHCs emission

Male harassment influences female movements and associations in Grevy's zebra (Equus grevyi)

OpenAIRE

Siva R. Sundaresan; Ilya R. Fischhoff; DI Rubenstein

2007-01-01

In traditional models for social organization, female movements and association patterns track resource distribution, whereas males track females. More recently, this model has been expanded to include feedback effects of male behavior, especially sexual harassment, on female decisions. In Grevy's zebra (Equus grevyi), males defend territories containing resources attractive to females, who form unstable groups. Past research has explained female behavior based on resource distribution and ne...

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: BIRDS (Bird Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, and gulls/terns in Northwest...

Effect of visual distraction and auditory feedback on patient effort during robot-assisted movement training after stroke.

Science.gov (United States)

Secoli, Riccardo; Milot, Marie-Helene; Rosati, Giulio; Reinkensmeyer, David J

2011-04-23

Practicing arm and gait movements with robotic assistance after neurologic injury can help patients improve their movement ability, but patients sometimes reduce their effort during training in response to the assistance. Reduced effort has been hypothesized to diminish clinical outcomes of robotic training. To better understand patient slacking, we studied the role of visual distraction and auditory feedback in modulating patient effort during a common robot-assisted tracking task. Fourteen participants with chronic left hemiparesis from stroke, five control participants with chronic right hemiparesis and fourteen non-impaired healthy control participants, tracked a visual target with their arms while receiving adaptive assistance from a robotic arm exoskeleton. We compared four practice conditions: the baseline tracking task alone; tracking while also performing a visual distracter task; tracking with the visual distracter and sound feedback; and tracking with sound feedback. For the distracter task, symbols were randomly displayed in the corners of the computer screen, and the participants were instructed to click a mouse button when a target symbol appeared. The sound feedback consisted of a repeating beep, with the frequency of repetition made to increase with increasing tracking error. Participants with stroke halved their effort and doubled their tracking error when performing the visual distracter task with their left hemiparetic arm. With sound feedback, however, these participants increased their effort and decreased their tracking error close to their baseline levels, while also performing the distracter task successfully. These effects were significantly smaller for the participants who used their non-paretic arm and for the participants without stroke. Visual distraction decreased participants effort during a standard robot-assisted movement training task. This effect was greater for the hemiparetic arm, suggesting that the increased demands associated

Tracking the mechanical dynamics of human embryonic stem cell chromatin

Directory of Open Access Journals (Sweden)

Hinde Elizabeth

2012-12-01

Full Text Available Abstract Background A plastic chromatin structure has emerged as fundamental to the self-renewal and pluripotent capacity of embryonic stem (ES cells. Direct measurement of chromatin dynamics in vivo is, however, challenging as high spatiotemporal resolution is required. Here, we present a new tracking-based method which can detect high frequency chromatin movement and quantify the mechanical dynamics of chromatin in live cells. Results We use this method to study how the mechanical properties of chromatin movement in human embryonic stem cells (hESCs are modulated spatiotemporally during differentiation into cardiomyocytes (CM. Notably, we find that pluripotency is associated with a highly discrete, energy-dependent frequency of chromatin movement that we refer to as a ‘breathing’ state. We find that this ‘breathing’ state is strictly dependent on the metabolic state of the cell and is progressively silenced during differentiation. Conclusions We thus propose that the measured chromatin high frequency movements in hESCs may represent a hallmark of pluripotency and serve as a mechanism to maintain the genome in a transcriptionally accessible state. This is a result that could not have been observed without the high spatial and temporal resolution provided by this novel tracking method.

Can variation in risk of nest predation explain altitudinal migration in tropical birds?

Science.gov (United States)

Boyle, W Alice

2008-03-01

Migration is among the best studied of animal behaviors, yet few empirical studies have tested hypotheses explaining the ultimate causes of these cyclical annual movements. Fretwell's (1980) hypothesis predicts that if nest predation explains why many tropical birds migrate uphill to breed, then predation risk must be negatively associated with elevation. Data from 385 artificial nests spanning 2,740 m of elevation on the Atlantic slope of Costa Rica show an overall decline in predation with increasing elevation. However, nest predation risk was highest at intermediate elevations (500-650 m), not at lowest elevations. The proportion of nests depredated by different types of predators differed among elevations. These results imply that over half of the altitudinal migrant bird species in this region migrate to safer breeding areas than their non-breeding areas, suggesting that variation in nest predation risk could be an important benefit of uphill migrations of many species.

ISAT: The mega-fauna acoustic tracking system

KAUST Repository

De la Torre, Pedro

2013-06-01

The acoustic tracking module of the Integrated Satellite and Acoustic Telemetry (iSAT) system is discussed in detail. iSAT is capable of detecting the relative direction of an acoustic source by measuring the order of arrival (OOA) of the acoustic signal to each hydrophone in a triangular array. The characteristics of the hydrophones, the projector, and the target acoustic signal used for iSAT are described. Initially it is designed to study the movements of whale sharks (Rhincodon typus), but it could potentially be used to describe high resolution movements of other marine species. © 2013 IEEE.

Forest bird monitoring protocol for strategic habitat conservation and endangered species management on O'ahu Forest National Wildlife Refuge, Island of O'ahu, Hawai'i

Science.gov (United States)

Camp, Richard J.; Gorresen, P. Marcos; Banko, Paul C.

2011-01-01

This report describes the results of a pilot forest bird survey and a consequent forest bird monitoring protocol that was developed for the O'ahu Forest National Wildlife Refuge, O'ahu Island, Hawai'i. The pilot survey was conducted to inform aspects of the monitoring protocol and to provide a baseline with which to compare future surveys on the Refuge. The protocol was developed in an adaptive management framework to track bird distribution and abundance and to meet the strategic habitat conservation requirements of the Refuge. Funding for this research was provided through a Science Support Partnership grant sponsored jointly by the U.S. Geological Survey (USGS) and the U.S. Fish and Wildlife Service (USFWS).

Birds as predators in tropical agroforestry systems.

Science.gov (United States)

Van Bael, Sunshine A; Philpott, Stacy M; Greenberg, Russell; Bichier, Peter; Barber, Nicholas A; Mooney, Kailen A; Gruner, Daniel S

2008-04-01

Insectivorous birds reduce arthropod abundances and their damage to plants in some, but not all, studies where predation by birds has been assessed. The variation in bird effects may be due to characteristics such as plant productivity or quality, habitat complexity, and/or species diversity of predator and prey assemblages. Since agroforestry systems vary in such characteristics, these systems provide a good starting point for understanding when and where we can expect predation by birds to be important. We analyze data from bird exclosure studies in forests and agroforestry systems to ask whether birds consistently reduce their arthropod prey base and whether bird predation differs between forests and agroforestry systems. Further, we focus on agroforestry systems to ask whether the magnitude of bird predation (1) differs between canopy trees and understory plants, (2) differs when migratory birds are present or absent, and (3) correlates with bird abundance and diversity. We found that, across all studies, birds reduce all arthropods, herbivores, carnivores, and plant damage. We observed no difference in the magnitude of bird effects between agroforestry systems and forests despite simplified habitat structure and plant diversity in agroforests. Within agroforestry systems, bird reduction of arthropods was greater in the canopy than the crop layer. Top-down effects of bird predation were especially strong during censuses when migratory birds were present in agroforestry systems. Importantly, the diversity of the predator assemblage correlated with the magnitude of predator effects; where the diversity of birds, especially migratory birds, was greater, birds reduced arthropod densities to a greater extent. We outline potential mechanisms for relationships between bird predator, insect prey, and habitat characteristics, and we suggest future studies using tropical agroforests as a model system to further test these areas of ecological theory.

Contextual effects on motion perception and smooth pursuit eye movements.

Science.gov (United States)

Spering, Miriam; Gegenfurtner, Karl R

2008-08-15

Smooth pursuit eye movements are continuous, slow rotations of the eyes that allow us to follow the motion of a visual object of interest. These movements are closely related to sensory inputs from the visual motion processing system. To track a moving object in the natural environment, its motion first has to be segregated from the motion signals provided by surrounding stimuli. Here, we review experiments on the effect of the visual context on motion processing with a focus on the relationship between motion perception and smooth pursuit eye movements. While perception and pursuit are closely linked, we show that they can behave quite distinctly when required by the visual context.

Combining direct and indirect tracking techniques to assess the impact of sub-Saharan conditions on cross-continental songbird migration

DEFF Research Database (Denmark)

Pedersen, Lykke; Fraser, Kevin C.; Kyser, T. Kurt

2016-01-01

Understanding how events throughout the annual cycle interact to influence individual fitness and hence population dynamics is crucial to optimize conservation strategies for migratory birds. Despite major advancements in technology, direct tracking devices for passerine songbirds are still limited...

Simultaneous nano-tracking of multiple motor proteins via spectral discrimination of quantum dots.

Science.gov (United States)

Kakizuka, Taishi; Ikezaki, Keigo; Kaneshiro, Junichi; Fujita, Hideaki; Watanabe, Tomonobu M; Ichimura, Taro

2016-07-01

Simultaneous nanometric tracking of multiple motor proteins was achieved by combining multicolor fluorescent labeling of target proteins and imaging spectroscopy, revealing dynamic behaviors of multiple motor proteins at the sub-diffraction-limit scale. Using quantum dot probes of distinct colors, we experimentally verified the localization precision to be a few nanometers at temporal resolution of 30 ms or faster. One-dimensional processive movement of two heads of a single myosin molecule and multiple myosin molecules was successfully traced. Furthermore, the system was modified for two-dimensional measurement and applied to tracking of multiple myosin molecules. Our approach is useful for investigating cooperative movement of proteins in supramolecular nanomachinery.

What triggers catch-up saccades during visual tracking?

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de Brouwer, Sophie; Yuksel, Demet; Blohm, Gunnar; Missal, Marcus; Lefèvre, Philippe

2002-03-01

When tracking moving visual stimuli, primates orient their visual axis by combining two kinds of eye movements, smooth pursuit and saccades, that have very different dynamics. Yet, the mechanisms that govern the decision to switch from one type of eye movement to the other are still poorly understood, even though they could bring a significant contribution to the understanding of how the CNS combines different kinds of control strategies to achieve a common motor and sensory goal. In this study, we investigated the oculomotor responses to a large range of different combinations of position error and velocity error during visual tracking of moving stimuli in humans. We found that the oculomotor system uses a prediction of the time at which the eye trajectory will cross the target, defined as the "eye crossing time" (T(XE)). The eye crossing time, which depends on both position error and velocity error, is the criterion used to switch between smooth and saccadic pursuit, i.e., to trigger catch-up saccades. On average, for T(XE) between 40 and 180 ms, no saccade is triggered and target tracking remains purely smooth. Conversely, when T(XE) becomes smaller than 40 ms or larger than 180 ms, a saccade is triggered after a short latency (around 125 ms).

Efficient Parallel Sorting for Migrating Birds Optimization When Solving Machine-Part Cell Formation Problems

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Ricardo Soto

2016-01-01

Full Text Available The Machine-Part Cell Formation Problem (MPCFP is a NP-Hard optimization problem that consists in grouping machines and parts in a set of cells, so that each cell can operate independently and the intercell movements are minimized. This problem has largely been tackled in the literature by using different techniques ranging from classic methods such as linear programming to more modern nature-inspired metaheuristics. In this paper, we present an efficient parallel version of the Migrating Birds Optimization metaheuristic for solving the MPCFP. Migrating Birds Optimization is a population metaheuristic based on the V-Flight formation of the migrating birds, which is proven to be an effective formation in energy saving. This approach is enhanced by the smart incorporation of parallel procedures that notably improve performance of the several sorting processes performed by the metaheuristic. We perform computational experiments on 1080 benchmarks resulting from the combination of 90 well-known MPCFP instances with 12 sorting configurations with and without threads. We illustrate promising results where the proposal is able to reach the global optimum in all instances, while the solving time with respect to a nonparallel approach is notably reduced.

Use of bird carcass removals by urban scavengers to adjust bird-window collision estimates

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Justine A. Kummer

2016-12-01

Full Text Available Carcass removal by scavengers has been identified as one of the largest biases in estimating bird mortality from anthropogenic sources. Only two studies have examined carcass removal by scavengers in an urban environment, and previous estimates of bird-window collision mortality at houses have relied on carcass removal rates from wind turbine studies. We placed a bird carcass and time-lapse camera at 44 houses in Edmonton, Alberta. In total, 166 7-day trials were conducted throughout 2015. Time-to-event (survival analysis was used to identify covariates that affected removal. The carcass removal rate was determined for use in estimating the number of birds killed from bird-window collisions at houses in Alberta. In total, 67.5% of carcasses were removed. The date the carcass was placed, the year the house was built, and the level of development within 50 m of the house were the covariates that had the largest effect on carcass removal. In calculating our removal rate, the number of detected carcasses in the first 24 hours was adjusted by 1.47 to account for removal by scavengers. Previously collected citizen science data were used to create an estimate of 957,440 bird deaths each year in Alberta as a result of bird-window collisions with houses. This number is based on the most detailed bird-window collision study at houses to date and a carcass removal study conducted in the same area. Similar localized studies across Canada will need to be completed to reduce the biases that exist with the previous bird-window collision mortality estimate for houses in Canada.

Can smartwatches replace smartphones for posture tracking?

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Mortazavi, Bobak; Nemati, Ebrahim; VanderWall, Kristina; Flores-Rodriguez, Hector G; Cai, Jun Yu Jacinta; Lucier, Jessica; Naeim, Arash; Sarrafzadeh, Majid

2015-10-22

This paper introduces a human posture tracking platform to identify the human postures of sitting, standing or lying down, based on a smartwatch. This work develops such a system as a proof-of-concept study to investigate a smartwatch's ability to be used in future remote health monitoring systems and applications. This work validates the smartwatches' ability to track the posture of users accurately in a laboratory setting while reducing the sampling rate to potentially improve battery life, the first steps in verifying that such a system would work in future clinical settings. The algorithm developed classifies the transitions between three posture states of sitting, standing and lying down, by identifying these transition movements, as well as other movements that might be mistaken for these transitions. The system is trained and developed on a Samsung Galaxy Gear smartwatch, and the algorithm was validated through a leave-one-subject-out cross-validation of 20 subjects. The system can identify the appropriate transitions at only 10 Hz with an F-score of 0.930, indicating its ability to effectively replace smart phones, if needed.

Quantifying movement demands of AFL football using GPS tracking.

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Wisbey, Ben; Montgomery, Paul G; Pyne, David B; Rattray, Ben

2010-09-01

Global positioning system (GPS) monitoring of movement patterns is widespread in elite football including the Australian Football League (AFL). However documented analysis of this activity is lacking. We quantified the movement patterns of AFL football and differences between nomadic (midfield), forward and defender playing positions, and determined whether the physical demands have increased over a four season period. Selected premiership games were monitored during the 2005 (n=80 game files), 2006 (n=244), 2007 (n=632) and 2008 (n=793) AFL seasons. Players were fitted with a shoulder harness containing a GPS unit. GPS data were downloaded after games and the following measures extracted: total distance (km), time in various speed zones, maximum speed, number of surges, accelerations, longest continuous efforts and a derived exertion index representing playing intensity. In 2008 nomadic players covered per game 3.4% more total distance (km), had 4.8% less playing time (min), a 17% higher exertion index (per min), and 23% more time running >18kmh(-1) than forwards and defenders (all p<0.05). Physical demands were substantially higher in the 2008 season compared with 2005: an 8.4% increase in mean speed, a 14% increase in intensity (exertion index) and a 9.0% decrease in playing time (all p<0.05). Nomadic players in AFL work substantially harder than forwards and defenders in covering more ground and at higher running intensities. Increases in the physical demands of AFL football were evident between 2005 and 2008. The increasing speed of the game has implications for game authorities, players and coaching staff.

Music for the birds: effects of auditory enrichment on captive bird species.

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Robbins, Lindsey; Margulis, Susan W

2016-01-01

With the increase of mixed species exhibits in zoos, targeting enrichment for individual species may be problematic. Often, mammals may be the primary targets of enrichment, yet other species that share their environment (such as birds) will unavoidably be exposed to the enrichment as well. The purpose of this study was to determine if (1) auditory stimuli designed for enrichment of primates influenced the behavior of captive birds in the zoo setting, and (2) if the specific type of auditory enrichment impacted bird behavior. Three different African bird species were observed at the Buffalo Zoo during exposure to natural sounds, classical music and rock music. The results revealed that the average frequency of flying in all three bird species increased with naturalistic sounds and decreased with rock music (F = 7.63, df = 3,6, P = 0.018); vocalizations for two of the three species (Superb Starlings and Mousebirds) increased (F = 18.61, df = 2,6, P = 0.0027) in response to all auditory stimuli, however one species (Lady Ross's Turacos) increased frequency of duetting only in response to rock music (X(2) = 18.5, df = 2, P < 0.0001). Auditory enrichment implemented for large mammals may influence behavior in non-target species as well, in this case leading to increased activity by birds. © 2016 Wiley Periodicals, Inc.

Automated tracking of animal posture and movement during exploration and sensory orientation behaviors.

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Alex Gomez-Marin

Full Text Available The nervous functions of an organism are primarily reflected in the behavior it is capable of. Measuring behavior quantitatively, at high-resolution and in an automated fashion provides valuable information about the underlying neural circuit computation. Accordingly, computer-vision applications for animal tracking are becoming a key complementary toolkit to genetic, molecular and electrophysiological characterization in systems neuroscience.We present Sensory Orientation Software (SOS to measure behavior and infer sensory experience correlates. SOS is a simple and versatile system to track body posture and motion of single animals in two-dimensional environments. In the presence of a sensory landscape, tracking the trajectory of the animal's sensors and its postural evolution provides a quantitative framework to study sensorimotor integration. To illustrate the utility of SOS, we examine the orientation behavior of fruit fly larvae in response to odor, temperature and light gradients. We show that SOS is suitable to carry out high-resolution behavioral tracking for a wide range of organisms including flatworms, fishes and mice.Our work contributes to the growing repertoire of behavioral analysis tools for collecting rich and fine-grained data to draw and test hypothesis about the functioning of the nervous system. By providing open-access to our code and documenting the software design, we aim to encourage the adaptation of SOS by a wide community of non-specialists to their particular model organism and questions of interest.

Characterization of low pathogenicity avian influenza viruses isolated from wild birds in Mongolia 2005 through 2007

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Sodnomdarjaa Ruuragchaa

2009-11-01

Full Text Available Abstract Background Since the emergence of H5N1 high pathogenicity (HP avian influenza virus (AIV in Asia, numerous efforts worldwide have focused on elucidating the relative roles of wild birds and domestic poultry movement in virus dissemination. In accordance with this a surveillance program for AIV in wild birds was conducted in Mongolia from 2005-2007. An important feature of Mongolia is that there is little domestic poultry production in the country, therefore AIV detection in wild birds would not likely be from spill-over from domestic poultry. Results During 2005-2007 2,139 specimens representing 4,077 individual birds of 45 species were tested for AIV by real time RT-PCR (rRT-PCR and/or virus isolation. Bird age and health status were recorded. Ninety rRT-PCR AIV positive samples representing 89 individual birds of 19 species including 9 low pathogenicity (LP AIVs were isolated from 6 species. A Bar-headed goose (Anser indicus, a Whooper swan (Cygnus cygnus and 2 Ruddy shelducks (Tadorna ferruginea were positive for H12N3 LP AIV. H16N3 and H13N6 viruses were isolated from Black-headed gulls (Larus ridibundus. A Red-crested pochard (Rhodonessa rufina and 2 Mongolian gulls (Larus vagae mongolicus were positive for H3N6 and H16N6 LP AIV, respectively. Full genomes of each virus isolate were sequenced and analyzed phylogenetically and were most closely related to recent European and Asian wild bird lineage AIVs and individual genes loosely grouped by year. Reassortment occurred within and among different years and subtypes. Conclusion Detection and/or isolation of AIV infection in numerous wild bird species, including 2 which have not been previously described as hosts, reinforces the wide host range of AIV within avian species. Reassortment complexity within the genomes indicate the introduction of new AIV strains into wild bird populations annually, however there is enough over-lap of infection for reassortment to occur. Further work is

A model of loggerhead sea turtle (Caretta caretta habitat and movement in the oceanic North Pacific.

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