A Novel Frequency Analysis Method for Assessing Kir2.1 and Nav1.5 Currents

Voltage clamping is an important tool for measuring individual currents from an electrically active cell. However, it is difficult to isolate individual currents without pharmacological or voltage inhibition. Herein, we present a technique that involves inserting a noise function into a standard voltage step protocol, which allows one to characterize the unique frequency response of an ion channel at different step potentials. Specifically, we compute the fast Fourier transform for a family of current traces at different step potentials for the inward rectifying potassium channel, Kir2.1, and the channel encoding the cardiac fast sodium current, Nav1.5. Each individual frequency magnitude, as a function of voltage step, is correlated to the peak current produced by each channel. The correlation coefficient vs. frequency relationship reveals that these two channels are associated with some unique frequencies with high absolute correlation. The individual IV relationship can then be recreated using only the unique frequencies with magnitudes of high absolute correlation. Thus, this study demonstrates that ion channels may exhibit unique frequency responses

Teaching Object-Oriented Programming in Secondary Schools Using Swarm Robotics

The recent inclusion of computer science in the British secondary school education system has resulted in existing teaching staff who are not able to effectively deliver the curriculum. Existing environments—such as Greenfoot—help substantially but anecdotal evidence suggests that many pupils still struggle with some aspects of the computer science curriculum. This paper presents a workshop for teaching pupils about method calls in object-oriented programming, using swarm robotics and the firefly synchronisation algorithm as inspiration

How Swarms Build Cognitive Maps

. Swarms of social insects construct trails and networks of regular traffic via a process of pheromone laying and following. These patterns constitute what is known in brain science as a cognitive map. The main difference lies in the fact that the insects write their spatial memories in the environment, while the mammalian cognitive map lies inside the brain. This analogy can be more than a poetic image, and can be further justified by a direct comparison with the neural processes associated with the construction of cognitive maps in the hippocampus. We investigate via analysis and numerical simulation the formation of trails and networks in a collection of insect-like agents. The agents interact in simple ways which are determined by experiments with real ants. 1 Introduction The self-organization of neurons into a brain-like structure, and the selforganization of ants into a swarm are similar in many respects. The former, for obvious reasons, has received more attention recently. Ho..

Trail and teritorial communication in social insects

The social properties of insect colonies are sometimes described in seemingly contradictory terms. As pinnacles of biological complexity they are superorganisms and their emergent, colony-level characteristics are often referred to in terms of their elaborate and sophisticated nature. Yet the mechanisms that mediate social interactions and group phenomena, after empirical or theoretical analysis, are simple and parsimonious. This complexity-mediated-by-simplicity paradigm provides a heuristic approach to the analysis of the basic behavioral characteristics of the individual members of an insect society and the regulatory mechanisms of cooperative response, which are the fundamental elements from which colony level behavior is derived. Inevitably, the dissection and reconstruction of insect social organization involves semiochemicals, because the principal sensory modality of integration, social coordination, and assembly of colony-level patternsis olfaction