Lethbridge, Canada
Lethbridge, Canada

The University of Lethbridge is a publicly funded comprehensive academic and research university, founded in the liberal education tradition, located in Lethbridge, Alberta, Canada, with two other urban campuses in Calgary and Edmonton. The main building sits among the coulees on the west side of the Oldman River.The U of L is a member of the Alberta Rural Development Network. Wikipedia.

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Most cognitive functions are based on computations that take place in the cerebral cortex, composed of a larger number of areas, each with a complex anatomical structure, with neurons of different types and in different layers interacting according to a precise scheme. The anatomical organization of cortical areas is similar, with some modulation according to its sensory, motor or associative function. Several areas have a columnar organization, but in all areas a similar vertical organization of cortical modules is repeated, suggesting that the same fundamental computation scheme is carried out. Despite the large amount of available data, this processing capability of the cortical module is still poorly understood. Two key technological advances to explore cortical computation have been ensemble electrophysiology, the use of multiple electrodes to record groups of neurons, and optogenetics. However, the optogenetic tools are still critically lacking in layer and cell-type specificity, and the recording techniques still do not attain the yields necessary to properly characterize the cortical microcircuit. To overcome these limitations, we propose a new probe that dramatically increases the density of electrodes providing an unprecedented view of currents in the extracellular medium. This will be complemented with an optical stimulator, capable of activating excitatory and inhibitory channelrhodopsins with a 100 m resolution. We will take full advantage of the rich data that can be obtained with these new devices by producing new strategies for signal classification, to locate cells in cortical layers and assign them to a cell type based on the spatiotemporal fingerprint generated at each action potential. We will analyze cortical function at multiple scales in a number of contexts, from memory formation, to ongoing processing during decision making, and to sensorimotor integration for actions, advancing our understanding of cortical representations.

Johnson K.R.D.,University of Lethbridge | Hayes P.G.,University of Lethbridge
Chemical Society Reviews | Year: 2013

Cyclometalative C-H bond activation is a process that is commonly encountered in the field of organometallic chemistry. In rare earth and actinide complexes, ligand cyclometalation is most prevalent in highly reactive alkyl and hydrido species. Numerous factors promote ligand cyclometalation and influence the rate at which it occurs. This tutorial review discusses key issues relevant to ligand cyclometalation in rare earth and actinide complexes, including kinetic and mechanistic considerations. A variety of examples is presented for a wide range of ligand types and metals, the scope of which is intended to include routine cases, while also highlighting exceptional cyclometalation reactions that lead to unusual bonding modes. The reaction chemistry of cyclometalated rare earth and actinide complexes with various small molecule substrates (e.g. phenol, anilines, triethylammonium salts, alkynes, olefins, hydrogen and hydrocarbons) is also outlined. This journal is © The Royal Society of Chemistry.

Ali A.F.,University of Lethbridge
Classical and Quantum Gravity | Year: 2011

A possible discrepancy has been found between the results of a neutron interferometry experiment and quantum mechanics. This experiment suggests that the weak equivalence principle is violated at small length scales, which quantum mechanics cannot explain. In this paper, we investigated whether the generalized uncertainty principle (GUP), proposed by some approaches to quantum gravity such as string theory and doubly special relativity theories, can explain the violation of the weak equivalence principle at small length scales. We also investigated the consequences of the GUP on the Liouville theorem in statistical mechanics. We have found a new form of invariant phase space in the presence of GUP. This result should modify the density states and affect the calculation of the entropy bound of local quantum field theory, the cosmological constant, black body radiation, etc. Furthermore, such modification may have observable consequences at length scales much larger than the Planck scale. This modification leads to a √A-type correction to the bound of the maximal entropy of a bosonic field which would definitely shed some light on the holographic theory. © 2011 IOP Publishing Ltd.

Speech productions of 40 English- and 40 Japanese-speaking children (aged 2-5) were examined and compared with the speech produced by 20 adult speakers (10 speakers per language). Participants were recorded while repeating words that began with "s" and "sh" sounds. Clear language-specific patterns in adults' speech were found, with English speakers differentiating "s" and "sh" in 1 acoustic dimension (i.e., spectral mean) and Japanese speakers differentiating the 2 categories in 3 acoustic dimensions (i.e., spectral mean, standard deviation, and onset F2 frequency). For both language groups, children's speech exhibited a gradual change from an early undifferentiated form to later differentiated categories. The separation processes, however, only occur in those acoustic dimensions used by adults in the corresponding languages. © 2012 The Author. Child Development © 2012 Society for Research in Child Development, Inc.

Henzi S.P.,University of Lethbridge
Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Year: 2013

Primate social life and behaviour is contingent on a number of levels: phylogenetic, functional and proximate. Although this contingency is recognized by socioecological theory, variability in behaviour is still commonly viewed as 'noise' around a central tendency, rather than as a source of information. An alternative view is that selection has acted on social reaction norms that encompass demographic variation both between and within populations and demes. Here, using data from vervet monkeys (Chlorocebus aethiops pygerythrus), we illustrate how this alternative approach can provide a more nuanced account of social structure and its relation to contingent events at the ecological and demographic levels. Female vervets in our South African study population live in large groups, where they experience demographic stress and increased levels of feeding competition relative to an East African population in Amboseli, Kenya. Females in the South African population did not respond to this stress by intensifying competition for high-value grooming partners to help alleviate the effects of this stress, did not show the expected rank-related patterns of grooming, nor did they show any spatial association with their preferred grooming partners. Increased group size therefore resulted in a reorganization of female social engagement that was both qualitatively and quantitatively different to that seen elsewhere, and suggests that female vervets possess the flexibility to shift to alternative patterns of social engagement in response to contingent ecological and demographic conditions.

Das S.,University of Lethbridge
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

We compute quantum corrections to the Raychaudhuri equation by replacing classical geodesics with quantal (Bohmian) trajectories and show that they prevent focusing of geodesics and the formation of conjugate points. We discuss implications for the Hawking-Penrose singularity theorems and curvature singularities. © 2014 American Physical Society.

University of Lethbridge | Date: 2015-07-24

The disclosure provides an apparatus and method for assessing brain plasticity by measuring electrical brain biomarkers, for example, with a near real-time analysis of electrical brain biomarkers, where an increase or decrease in at least one biomarker is indicative of a state of brain plasticity in response to a stimulus or treatment. Brain plasticity can be measured with or without an added stimuli, for example, to determine the best time for learning. Also provided is a method for treating a neurological disease or trauma by applying an electrical or drug stimulus to a patient, where the stimulus is increased or decreased depending on the changes of electrical brain biomarker of the patient. This treatment can occur in near real-time, so a course of treatment can be tailored immediately to a patients needs.

Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: SPA.2012.2.2-01 | Award Amount: 2.59M | Year: 2013

For knowledge to progress in many aspects of astrophysics it is clear that we need to make observations at all wavelengths that at least match the spatial resolution achieved in the optical by the Hubble Space Telescope. This is especially true in the Far Infra-Red waveband (FIR - 30-300 micron - where our atmosphere is opaque) where the necessity of space borne experiments combined with long wavelengths makes achieving high spatial resolution particularly difficult. At present FIR observations lie in a resolution gap of 2 orders of magnitude represented by the James-Webb Space telescope in the mid-infrared on one side and the ALMA interferometer, in the sub-mm, on the other. Only with the development of space borne interferometers can we hope to bridge this divide. This project brings together the leading international experts on FIR space instrumentation and experienced astronomers in a unique collaborative effort to address the development needs of a high resolution FIR observatory through two major activities. Firstly to identify the scientific questions which require high spatial resolution observations in the FIR. We will translate these into the definition of an ambitious space mission and its associated key technologies. At the same time we will study a number of technologies relevant to space interferometers which are at a low Technology Readiness Level. These include free-space beam combination with cryogenic delay lines, deployable low-mass telescopes, accurate satellite position measurement techniques and advanced ground calibration scenarios. We will develop these technologies through a consortium of universities, research establishments and industry which combine the best academic and industrial expertise. The outcome of this work will advance the knowledge and technology required for a future FIR mission, consolidate the scientific community and bring world-wide expertise to the EU consortium. We will promote the results to a wider scientific community through a number of international workshops centred on the definition of a future FIR space mission.

University of Alberta and University of Lethbridge | Date: 2015-02-05

The disclosure provides methods for the treatment of skin disorders through the use of minimally invasive terahertz radiation. The method includes exposing skin cells to terahertz radiation in amount sufficient to modulate gene expression in the skin cells. The modulation of gene expression then results in a reduction of the disease state or aspects thereof in the exposed skin cells.

Rasmussen J.B.,University of Lethbridge
Journal of Animal Ecology | Year: 2010

1.This paper outlines a gradient-based model that can be used for isotopic signature source partitioning, even if source signatures are not distinct, as long as their spatial gradients differ. A model of this type is applied to the partitioning of autochthonous vs. allochthonous contribution to stream invertebrate d13C signatures, which has often been confounded by overlap in source signatures. 2. δ13C signatures of inorganic carbon and most autochthonous production exhibit pronounced gradients along rivers, being depleted relative to terrestrial signatures in upstream reaches, and enriched downstream. Terrestrial detritus, by contrast, exhibits no gradient. Thus terrestrial food consumption reduces downstream signature slopes in proportion to the amount of terrestrial food consumed. 3. The gradient-based mixing model produces estimates of the proportion of terrestrial consumption (pT) from signature slopes of consumers; pT estimates for invertebrate primary consumers were: herbivore/grazers (0·15) 1, indicating selective assimilation of the autochthonous component fromthe biofilms. ©2009 The Authors. Journal compilation ©2009 British Ecological Society.

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