A solar concentrating photovoltaic/thermal collector

This thesis discusses aspects of a novel solar concentrating photovoltaic / thermal (PV/T) collector that has been designed to produce both electricity and hot water. The motivation for the development of the Combined Heat and Power Solar (CHAPS) collector is twofold: in the short term, to produce photovoltaic power and solar hot water at a cost which is competitive with other renewable energy technologies, and in the longer term, at a cost which is lower than possible with current technologies. To the author’s knowledge, the CHAPS collector is the first PV/T system using a reflective linear concentrator with a concentration ratio in the range 20-40x. The work contained in this thesis is a thorough study of all facets of the CHAPS collector, through a combination of theoretical and experimental investigation. ..

Particle Swarm Optimization Using Multiple Neighborhood Connectivity And Winner Take All Activation Applied To Biophysical Models Of Inferior Colliculus Neurons

Age-related hearing loss is a prevalent neurological disorder, affecting as many as 63% of adults over the age of 70. The inability to hear and understand speech is a cause of much distress in aged individuals and is becoming a major public health concern as age-related hearing loss has also been correlated with other neurological disorders such as Alzheimer\u27s dementia. The Inferior Colliculus (IC) is a major integrative auditory center, receiving excitatory and inhibitory inputs from several brainstem nuclei. This complex balance of excitation and inhibition gives rise to complex neural responses, which are measured in terms of firing rate as a given parameter is varied. A major obstacle in understanding the mechanisms involved in generating normal and aberrant auditory responses is estimating the strength and tuning of excitatory and inhibitory inputs that are integrated to form the output firing of IC neurons. To better understand IC response generation, biophysically accurate, conductance-based computational models were used to recreate IC frequency tuning responses. The problem of fitting response curves in vivo was approached using particle swarm optimization, an optimization paradigm which mimics social networks of flocking birds to solve problems. A new social network modeling winner-take-all activation found in visual neuron coding was developed in which agents are divided into social hierarchies and compete for leadership rights. This social network has shown good performance in benchmark optimization problems and is used to recreate IC frequency tuning responses which can be used to further understand pathological aging in the auditory system

Reply: Is CD1a involved in antitumour immune responses during carcinogenesis?

© 2004 Cancer Research UKPresents a response by the authors to a letter to the editor about their article "Is CD1a involved in antitumour immune responses during carcinogenesis?," published in the February 23, 2004 issue of the "British Journal of Cancer"B.J. Coventry and S. Heinze

Jigging

Our thesis work is jigging in general, that is, the construction of a miniature jig in the laboratory, operation of the same, discussion of jigging principles, and a description with drawings of the jig constructed. Most of our time was spent on the mechanical construction of the jig which we leave to the Mining Department

Foraging behaviour of a blue banded bee, Amegilla chlorocyanea in greenhouses: implications for use as tomato pollinators

© INRA, DIB-AGIB, EDP Sciences 2007Blue-banded bees (Amegilla spp.) are Australian native buzz pollinators that are a promising alternative to the introduction of the bumblebee (Bombus terrestris) for use as pollinators of tomatoes in Australian greenhouses. The foraging behaviour of Amegilla chlorocyanea under greenhouse conditions was monitored in detail. Our results showed that female Amegilla are active foragers that make on average 9 pollen foraging flights per day. Using data about flower visitation, we estimated the number of actively nesting female bees needed for adequate pollination in a commercial greenhouse as 282 per hectare.Katja Hogendoorn, Steven Coventry and Michael Anthony Kelle

Analysis of the radiation flux profile along a PV through concentrator

The primary advantage of a PV concentrator is that concentrating light allows a significant reduction in the area of solar cell coverage, the main cost driver in a flat plate system. PV systems, whether flat plate or concentrating, normally have groups of solar cells connected in series in order to increase voltage and limit current. However, low illumination on a single cell proportionally reduces its current, and hence affects the performance of all other cells in series. Ideally, a reflective PV concentrator system will have high concentration, a uniform flux distribution, and low cost. However, it is difficult to obtain these three conditions simultaneously, as cost tends to increase with better mirror quality, improved tracking accuracy, and the use of secondary flux modifiers. Linear concentrators have the advantage of simpler and cheaper tracking and support structures than dishes; however, achieving a consistent flux profile on every cell along the focal line is challenging. The aim of this paper is to present results of direct measurements of the flux profile along the length of a single axis tracking trough, and to develop simulation techniques that allow the reasons for peaks and troughs in the flux profile to be better understood

A mixed-methods pilot study of the acceptability and effectiveness of a brief meditation and mindfulness intervention for people with diabetes and coronary heart disease.

PublishedClinical TrialJournal ArticleResearch Support, Non-U.S. Gov'tMindfulness-based interventions can successfully target negative perseverative cognitions such as worry and thought suppression, but their acceptability and effectiveness in people with long-term conditions is uncertain. We therefore pilot tested a six-week meditation and mindfulness intervention in people (n = 40) with diabetes mellitus and coronary heart disease. We used a sequential mixed-methods approach that measured change in worry and thought suppression and qualitatively explored acceptability, feasibility, and user experience with a focus group (n = 11) and in-depth interviews (n = 16). The intervention was highly acceptable, with 90% completing ≥5 sessions. Meditation and mindfulness skills led to improved sleep, greater relaxation, and more-accepting approaches to illness and illness experience. At the end of the six-week meditation course, worry, and thought suppression were significantly reduced. Positive impacts of mindfulness-based interventions on psychological health may relate to acquisition and development of meta-cognitive skills but this needs experimental confirmation.NIHR Collaboration for Leadership in Applied Health Research and Care forGreater Manchester

Dendritic cell density and activation status in human breast cancer – CD1a, CMRF-44, CMRF-56 and CD-83 expression

Low CD1a-positive putative dendritic cell numbers in human breast cancer has recently been described and may explain the apparent ‘poor immunogenicity’ previously reported in breast cancer. Little attention has been given to dendritic cell activation within the tumour microenvironment, which is another reason why the in-situ immune response may be severely deficient. We have therefore examined CD1a expression as a marker for dendritic cells, together with CMRF-44 and -56 as markers of dendritic cell activation status, in 40 human breast cancers. The results demonstrate few or no CD1a-positive putative dendritic cells and minimal or no expression of the dendritic cell activation markers. Both dendritic cell number and dendritic cell activation appear substantially deficient in human breast cancers, regardless of tumour histological grade