Rings of real functions in pointfree topology

AbstractThis paper deals with the algebra F(L) of real functions on a frame L and its subclasses LSC(L) and USC(L) of, respectively, lower and upper semicontinuous real functions. It is well known that F(L) is a lattice-ordered ring; this paper presents explicit formulas for its algebraic operations which allow to conclude about their behaviour in LSC(L) and USC(L).As applications, idempotent functions are characterized and previous pointfree results about strict insertion of functions are significantly improved: general pointfree formulations that correspond exactly to the classical strict insertion results of Dowker and Michael regarding, respectively, normal countably paracompact spaces and perfectly normal spaces are derived.The paper ends with a brief discussion concerning the frames in which every arbitrary real function on the α-dissolution of the frame is continuous

Hierarchical Chain Model of Spider Capture Silk Elasticity

Spider capture silk is a biomaterial with both high strength and high elasticity, but the structural design principle underlying these remarkable properties is still unknown. It was revealed recently by atomic force microscopy that, an exponential force--extension relationship holds both for capture silk mesostructures and for intact capture silk fibers [N. Becker et al., Nature Materials 2, 278 (2003)]. In this Letter a simple hierarchical chain model was proposed to understand and reproduce this striking observation. In the hierarchical chain model, a polymer is composed of many structural motifs which organize into structural modules and supra-modules in a hierarchical manner. Each module in this hierarchy has its own characteristic force. The repetitive patterns in the amino acid sequence of the major flagelliform protein of spider capture silk is in support of this model.Comment: 4 pages, 3 figures. Will be formally published in PR

OSM Regulation of Responses to TLR-ligands in HASMC

Allergic atopic asthma is a respiratory condition that involves immune responses to specific allergens resulting in coughing, wheezing, shortness of breath and tightness in the chest. During an atopic asthmatic attack, the immune system initiates cellular infiltration of lymphocytes and eosinophils, airway hyper-responsiveness and ECM remodeling, which manifests in lung dysfunction in chronic disease. ASMC have recently been shown to play a role in the inflammatory processes of asthma through the production of inflammatory mediators. Various cytokines and chemokines serve as stimulants for these pathways and therefore require further attention to examine inflammatory signaling. OSM, a member of the gp130 family of cytokines, is secreted by inflammatory cells and has been detected in the sputum of asthmatics. Previous findings have established the potential of OSM in induction of lung inflammation, its role in increasing ECM, and its potential role in asthma. Viral or bacterial infections cause asthma exacerbations which result in increased severity of symptoms. The innate immune system relies on pattern recognition receptors including the TLRs to recognize invading pathogens and activate cells such as macrophages and natural killer cells. Although there are a number of these TLRs, this project will focus on the role of TLR3 and TLR4 in ASMC. I generally hypothesized that OSM markedly increases lung cell airway smooth muscle cell responses to external stimulae, such as products of bacteria or viruses that activate toll-like receptors. This exacerbates inflammation and extracellular matrix remodeling which contributes to pathology in asthmatic patients. Findings in this thesis have demonstrated that OSM stimulation increases the production of various cytokines and chemokines and growth factors seen in asthma. Co-stimulations with OSM and TLR-ligands augmented the production of a variety of these inflammatory mediators in comparison to ligands alone. TLR responses were shown to be associated with TLR expression, at both the mRNA and protein level, as well through the activation of the JAK-STAT and NFκB pathways. These findings implicate ASMC in immunomodulatory roles in response to TLR-ligands and OSM, and could play a role in the increased severity of asthma seen during exacerbations.Master of Science (MSc

Alien Registration- Guerette, Phillip (Millinocket, Penobscot County)

https://digitalmaine.com/alien_docs/7146/thumbnail.jp

The Effects of Task Load on Heart Rate and Heart Rate Variability

The relationship between task load and cardiovascular measures was investigated during single- and dual-task performance. The results showed significant reductions in Heart Rate Variability and the Blood pressure component of the Power Spectral Density function during task performance. No significant changes in HR were seen from baseline to task. However, differences in directional responding between subjects seemed to have obscured these effects. When direction of the HR response was disregarded and absolute magnitude of response was analyzed, significant differences from baseline to task were seen. There was no difference in physiological responding from single- to dual-task trials. Future research examining instantaneous changes in HRV as a direct function of decrements in performance is suggested

Alien Registration- Guerette, Marie A. (Saint Agatha, Aroostook County)

https://digitalmaine.com/alien_docs/33254/thumbnail.jp

Hemispheric Effects of Response Hand and Concurrent Auditory and Visual Information Processing on Task Performance

Previous research (cf. Wickens, Mountford & Schreiner, 1981; Wickens & Sandry, 1982) has suggested that performance is facilitated by maintaining integrity between the hemisphere of information input, processing, and motor response. This task-hemispheric integrity has been found to exist during concurrent performance of verbal and spatial tasks, both of which are presented in a visual modality. The present study sought to examine whether task-hemispheric integrity exists during concurrent performance of a verbal and a spatial task when the verbal task is presented in an auditory modality and the spatial task(s) are presented in a visual modality. Fifty-six individuals (28M, 28F) performed an auditory dichotic listening task alone and concurrently with three spatial tasks, each loading on a different stage of information processing. The results indicate a differential effect of each of the spatial tasks on dichotic listening performance, with few reciprocal effects of the dichotic listening task on spatial task performance. Sex differences were also found on two of the spatial tasks. Potential theoretical and practical implications of the findings are discussed