Drone exploration of bat echolocation: A UAV-borne multimicrophone array to study bat echolocation.

Multimicrophone array techniques offer crucial insight into bat echolocation, yet they severely undersample the environments bats operate in as they are limited in geographic placement and mobility. UAVs are excellent candidates to greatly increase the environments in which such arrays can be deployed, but the impact of UAV noise on recording quality and the UAV's behavioral impact on the bats may affect usability. We developed a UAV-borne multimicrophone setup capable of recording bat echolocation across diverse environments.

Driving singing behaviour in songbirds using a multi-modal, multi-agent virtual environment.

Interactive biorobotics provides unique experimental potential to study the mechanisms underlying social communication but is limited by our ability to build expressive robots that exhibit the complex behaviours of birds and small mammals. An alternative to physical robots is to use virtual environments. Here, we designed and built a modular, audio-visual 2D virtual environment that allows multi-modal, multi-agent interaction to study mechanisms underlying social communication.

Directionality of nose-emitted echolocation calls from bats without a nose leaf ().

All echolocating bats and whales measured to date emit a directional bio-sonar beam that affords them a number of advantages over an omni-directional beam, i.e. reduced clutter, increased source level and inherent directional information.

From "ear" to there: a review of biorobotic models of auditory processing in lizards.

The peripheral auditory system of lizards has been extensively studied, because of its remarkable directionality. In this paper, we review the research that has been performed on this system using a biorobotic approach. The various robotic implementations developed to date, both wheeled and legged, of the auditory model exhibit strong phonotactic performance for two types of steering mechanisms-a simple threshold decision model and Braitenberg sensorimotor cross-couplings.

Clustering Emergency Department patients - an assessment of group normality.

This paper presents an investigation into clustering of vital signs from Emergency Department patients with an intention of uncovering distinct thresholds for groups of patients. Emergency Department clinicians have to deal with an enormous spectrum of symptoms and diseases. The variety in patients is a cause for false alarms which greatly burden clinicians.

A spatial compression technique for head-related transfer function interpolation and complexity estimation.

A head-related transfer function (HRTF) model employing Legendre polynomials (LPs) is evaluated as an HRTF spatial complexity indicator and interpolation technique in the azimuth plane. LPs are a set of orthogonal functions derived on the sphere which can be used to compress an HRTF dataset by transforming it into a lower dimensional space. The LP compression technique was applied to various HRTF datasets, both real and synthetic, to determine how much different HRTFs can be compressed with respect to their structural complexity and their spatial resolution.

Compression of head-related transfer function using autoregressive-moving-average models and Legendre polynomials.

Head-related transfer functions (HRTFs) are generally large datasets, which can be an important constraint for embedded real-time applications. A method is proposed here to reduce redundancy and compress the datasets. In this method, HRTFs are first compressed by conversion into autoregressive-moving-average (ARMA) filters whose coefficients are calculated using Prony's method.

Ultrasonic recording system without intrinsic limits.

Today state-of-the-art bioacoustic research requires high-sample-rate, multi-channel, and often long-term recording systems. Commercial systems are very costly. This paper proposes and demonstrates an ultrasonic recording system design that is arbitrarily scalable.

Reconstruction of the signal produced by a directional sound source from remote multi-microphone recordings.

A mathematical method for reconstructing the signal produced by a directional sound source from knowledge of the same signal in the far field, i.e., microphone recordings, is developed.

A method for estimating the orientation of a directional sound source from source directivity and multi-microphone recordings: principles and application.

Taking into account directivity of real sound sources makes it possible to try solving an interesting and biologically relevant problem: estimating the orientation in three-dimensional space of a directional sound source. The source, of known directivity, produces a broadband signal (in the ultrasonic range, in this application) that is recorded by microphones whose position with respect to source is known. An analytical method to process the recorded signals and estimate source orientation is developed in this paper.

A computational fluid dynamics model of viscous coupling of hairs.

Arrays of arthropod filiform hairs form highly sensitive mechanoreceptor systems capable of detecting minute air disturbances, and it is unclear to what extent individual hairs interact with one another within sensor arrays. We present a computational fluid dynamics model for one or more hairs, coupled to a rigid-body dynamics model, for simulating both biological (e.g.

Multi-stability and pattern-selection in oscillatory networks with fast inhibition and electrical synapses.

A model or hybrid network consisting of oscillatory cells interconnected by inhibitory and electrical synapses may express different stable activity patterns without any change of network topology or parameters, and switching between the patterns can be induced by specific transient signals. However, little is known of properties of such signals. In the present study, we employ numerical simulations of neural networks of different size composed of relaxation oscillators, to investigate switching between in-phase (IP) and anti-phase (AP) activity patterns.

Artificial intelligence and robotics in high throughput post-genomics.

The shift of post-genomics towards a systems approach has offered an ever-increasing role for artificial intelligence (AI) and robotics. Many disciplines (e.g.

An analysis of neural models for walking control.

A large space of different neural models exists from simple mathematical abstractions to detailed biophysical representations with strongly differing levels of complexity and biological relevance. Previous comparisons between models have looked at biological realism or mathematical tractability rather than expressive power. This paper, however, investigates whether more sophisticated models are better suited to a complex sensorimotor control task than simpler ones, or whether the more general nature of groups of the simpler neurons allows them to collectively solve complex tasks better despite their individual simplicity.

Kinase peptide specificity: improved determination and relevance to protein phosphorylation.

Specificity of phosphorylation is critical to signal transduction. Recent emphasis on colocalization of substrate and kinase has eclipsed emphasis on peptide specificity, i.e.

Chemokine stimulation of human peripheral blood T lymphocytes induces rapid dephosphorylation of ERM proteins, which facilitates loss of microvilli and polarization.

Lymphocyte microvilli mediate initial rolling-adhesion along endothelium but are lost during transmigration from circulation to tissue. However, the mechanism for resorption of lymphocyte microvilli remains unexplored. We show that chemokine stimulation of human peripheral blood T (PBT) cells is sufficient to induce rapid resorption of microvilli.