Introducing spatial information into predictive NF-kappa B modelling - an agent-based approach

Nature is governed by local interactions among lower-level sub-units, whether at the cell, organ, organism, or colony level. Adaptive system behaviour emerges via these interactions, which integrate the activity of the sub-units. To understand the system level it is necessary to understand the underlying local interactions. Successful models of local interactions at different levels of biological organisation, including epithelial tissue and ant colonies, have demonstrated the benefits of such 'agent-based' modelling [1-4]. Here we present an agent-based approach to modelling a crucial biological system the intracellular NF-kappa B signalling pathway. The pathway is vital to immune response regulation, and is fundamental to basic survival in a range of species [5-7]. Alterations in pathway regulation underlie a variety of diseases, including atherosclerosis and arthritis. Our modelling of individual molecules, receptors and genes provides a more comprehensive outline of regulatory network mechanisms than previously possible with equation-based approaches [8]. The method also permits consideration of structural parameters in pathway regulation; here we predict that inhibition of NF-kappa B is directly affected by actin filaments of the cytoskeleton sequestering excess inhibitors, therefore regulating steady-state and feedback behaviour

Predicting athletic performance: the effects of judgment and motivation

The purpose of this study was to examine the influence of athlete motivation and judgment on the relationship between athletic ability and athletic performance. Much existing empirical literature has focused on motivation and cognitive ability in relation to athletic performance, but athlete judgment has received relatively little research attention. It was hypothesized that high performers will have stronger judgment and motivation scores than will lower performers. Results suggest the ability to make strategic decisions as operationalized by Systemic Judgment may be predictive of Athletic Performance

Evaluation of a cheap ultrasonic stage for light source coherence function measurement, optical coherence tomography and dynamic focusing

We evaluate the performance of a cheap ultrasonic stage in setups related to optical coherence tomography. The stage was used in several configurations: (1) optical delay line in an optical coherence tomography (OCT) setup; (2) as a delay line measuring coherence function of a low coherence source (e. g. superluminescent diode) and (3) in a dynamic focusing arrangement. The results are as follows: the stage is suitable for coherence function measurement (coherence length up to 70 mu m) of the light source and dynamic focusing. We found it unsuitable for OCT due to an unstable velocity profile. Despite this, the velocity profile has a repeatable shape (4% over 1000 A-scans) and slight modifications to the stage promise wider applications

Long Memory Regressors and Predictive Regressions: A two-stage rebalancing approach

Predictability tests with long memory regressors may entail both size distortion and incompatibility between the orders of integration of the dependent and independent variables. Addressing both problems simultaneously, this paper proposes a two-step procedure that rebalances the predictive regression by fractionally differencing the predictor based on a first-stage estimation of the memory parameter. Extensive simulations indicate that our procedure has good size, is robust to estimation error in the first stage, and can yield improved power over cases in which an integer order is assumed for the regressor. We also extend our approach beyond the standard predictive regression context to cases in which the dependent variable is also fractionally integrated, but not cointegrated with the regressor. We use our procedure to provide a valid test of forward rate unbiasedness that allows for a long memory forward premium

Tensin1 expression and function in chronic obstructive pulmonary disease

open access articleChronic obstructive pulmonary disease (COPD) constitutes a major cause of morbidity and mortality. Genome wide association studies have shown significant associations between airflow obstruction or COPD with a non-synonymous SNP in the TNS1 gene, which encodes tensin1. However, the expression, cellular distribution and function of tensin1 in human airway tissue and cells are unknown. We therefore examined these characteristics in tissue and cells from controls and people with COPD or asthma. Airway tissue was immunostained for tensin1. Tensin1 expression in cultured human airway smooth muscle cells (HASMCs) was evaluated using qRT-PCR, western blotting and immunofluorescent staining. siRNAs were used to downregulate tensin1 expression. Tensin1 expression was increased in the airway smooth muscle and lamina propria in COPD tissue, but not asthma, when compared to controls. Tensin1 was expressed in HASMCs and upregulated by TGFβ1. TGFβ1 and fibronectin increased the localisation of tensin1 to fibrillar adhesions. Tensin1 and α-smooth muscle actin (αSMA) were strongly co-localised, and tensin1 depletion in HASMCs attenuated both αSMA expression and contraction of collagen gels. In summary, tensin1 expression is increased in COPD airways, and may promote airway obstruction by enhancing the expression of contractile proteins and their localisation to stress fibres in HASMCs

Primary Encounters:towards a conceptual model of place relations in outdoor adventure education

Outdoor adventure education (OAE) was formally introduced in the early-mid 1900s to address certain societal ills. At the time, the focus was on the decline of physical and moral character in young boys, and the outdoors was seen as an ideal environment to address these concerns. In today’s culture, however, increasing awareness of environmental concerns has highlighted a need for pedagogy focused on human-place relations leading to moral change that inspires pro-environmental behaviours. A growing body of literature suggests that OAE experiences contribute to human relationships with the more-than-human world. However, a thematic analysis of the literature reveals a disconnect between the sociocultural foundations of OAE pedagogy, the onto-epistemological assumptions that inform pedagogy, and the resulting human-nature relations. Additionally, the literature does not adequately address the nature of relationship or how ‘relationship’ might translate into behaviours. This thesis employs a phenomenological lens to the question of relationship, challenging the onto-epistemological foundations of OAE pedagogy that are still influenced by problematic sociocultural structures. I argue that the roots of traditional OAE pedagogy encourage adversarial human-nature relations and suggest new onto-epistemological structures that encourage a different quality of relations leading to a sense of kinship and an ethic of care. Martin Buber’s philosophy of dialogue, experiences of the natural sublime, and indigenous ontologies are combined to suggest a phenomenon of primary encounters that has the potential to shift onto-epistemological assumptions and lead to more place-inclusive pedagogy. Drawing on my own experiences in OAE, I utilise autoethnography to both illustrate and test the concept of primary encounters. A thematic analysis of autoethnographic data reveals the ways in which embodiment, aesthetics, time, and practice contribute to a sense of mutuality and reciprocity between humans and the more-than-human world through primary encounters. Based on this autoethnographic data, techniques for applying primary encounters in OAE pedagogy are suggested

Origin of the inner ring in photoluminescence patterns of quantum well excitons

In order to explain and model the inner ring in photoluminescence (PL) patterns of indirect excitons in GaAs/AlGaAs quantum wells (QWs), we develop a microscopic approach formulated in terms of coupled nonlinear equations for the diffusion, thermalization and optical decay of the particles. The origin of the inner ring is unambiguously identified: it is due to cooling of indirect excitons in their propagation from the excitation spot. We infer that in our high-quality structures the in-plane diffusion coefficient is about 10-30cm^2/s and the amplitude of the disorder potential is about 0.45meV.Comment: 4 pages, 3 figure