Transient ventilation dynamics following a change in strength of a point source of heat

We investigate the transient ventilation flow within a confined ventilated space, with high- and low-level openings, when the strength of a low-level point source of heat is changed instantaneously. The steady-flow regime in the space involves a turbulent buoyant plume, which rises from the point source to a well-mixed warm upper layer. The steady-state height of the interface between this layer and the lower layer of exterior fluid is independent of the heat flux, but the upper layer becomes progressively warmer with heat flux. New analogue laboratory experiments of the transient adjustment between steady states identify that if the heat flux is increased, the continuing plume propagates to the top of the room forming a new, warmer layer. This layer gradually deepens, and as the turbulent plume entrains fluid from the original warm layer, the original layer is gradually depleted and disappears, and a new steady state is established. In contrast, if the source buoyancy flux is decreased, the continuing plume is cooler than the original plume, so that on reaching the interface it is of intermediate density between the original warm layer and the external fluid. The plume supplies a new intermediate layer, which gradually deepens with the continuing flow. In turn, the original upper layer becomes depleted, both as a result of being vented through the upper opening of the space, but also due to some penetrative entrainment of this layer by the plume, as the plume overshoots the interface before falling back to supply the new intermediate layer. We develop quantitative models which are in good accord with our experimental data, by combining classical plume theory with models of the penetrative entrainment for the case of a decrease in heating. Typically, we find that the effect of penetrative entrainment on the density of the intruding layer is relatively weak, provided the change in source strength is sufficiently large. However, penetrative entrainment measurably increases the rate at which the depth of the draining layer decreases. We conclude with a discussion of the importance of these results for the control of naturally ventilated spaces

Development of bioactive bread enriched with a seaweed peptide fraction with potential heart-health effects

Cardiovascular disease (CVD) is currently a global epidemic and is now the leading cause of mortality worldwide. The two major approaches for the prevention of CVD in the developed world are public health based Policies and clinical based Strategies focusing on high-risk individuals. Pharmaceutical companies have developed a range of treatments to tackle the causes of CVD and these include the development of anti-inflammatory, anti-hypertensive and anti-cholesterol drugs. However, unpleasant side-effects often exist with prescription drug-taking. Sourcing of natural food components from foods to provide protection against the development of CVDis a useful strategy to help combat illness. This thesis aims to utilise Irish macroalgae as a source of bioactive compounds which can be delivered in the food vehicle Bread to confer a Heart health effect to the consumer. Hypertension, one of the major risk factors associated with CVD may be controlled by inhibiting enzymes of the reninangiotensin aldosterone System (RAAS). Inhibition of the enzyme renin is an important strategy for the control of hypertension as renin is the initial and rate limiting enzyme of the RAAS. Inhibition of the circulating enzyme platelet activating factor acetylhydrolase (PAF-AH) is also important in the control of atherosclerosis development. PAF-AH generates two pro-inflammatory mediators lysophosphatidylcholine (LPC) and oxidized non-esterified fatty acids (oxNEFAs). Both of these mediators are involved in promotion of atherosclerotic plaque which may be lead to high blood pressure development. Macroalgae are part of the regular diet of many Asian cultures and have a tradition of being consumed in many coastal regions of the Western World. Regular consumption of macroalgae is associated with a decline in the prevalence of breast cancer and diabetes mellitus development. Species of macroalgae belonging to the group known as Rhodophyta or the red macroalgae are known to contain levels as high as 47 % protein. Several bioactive peptides, including ACE-Iinhibitory peptides were isolated previously from macroalgae protein extracts and hydrolysates. In this thesis the extraction and isolation of renin and PAF-AH inhibitory peptides from the macroalgae Palmaria palmata was carried out. The effectiveness of the isolated renin inhibitory tridecapeptide IRLIIVLMPILMA was further explored in terms of its capacity to survive gastrointestinal (GI) digestion and its ability to lower blood pressure in vivo in spontaneously hypertensive rats (SHRs). The Palmaria palmata protein hydrolysate from which these peptides were identified was subsequently incorporated in to bread and the effects of its addition were observed in terms of volume, colour, texture profile, moisture, crumb structure, sensory attributes and renin inhibitory activity

On the flexibility of the design of Multiple Try Metropolis schemes

The Multiple Try Metropolis (MTM) method is a generalization of the classical Metropolis-Hastings algorithm in which the next state of the chain is chosen among a set of samples, according to normalized weights. In the literature, several extensions have been proposed. In this work, we show and remark upon the flexibility of the design of MTM-type methods, fulfilling the detailed balance condition. We discuss several possibilities and show different numerical results

Critical animal and media studies: Expanding the understanding of oppression in communication research

Critical and communication studies have traditionally neglected the oppression conducted by humans towards other animals. However, our (mis)treatment of other animals is the result of public consent supported by a morally speciesist-anthropocentric system of values. Speciesism or anthroparchy, as much as any other mainstream ideologies, feeds the media and at the same time is perpetuated by them. The goal of this article is to remedy this neglect by introducing the subdiscipline of Critical Animal and Media Studies. Critical Animal and Media Studies takes inspiration both from critical animal studies – which is so far the most consolidated critical field of research in the social sciences addressing our exploitation of other animals – and from the normative-moral stance rooted in the cornerstones of traditional critical media studies. The authors argue that the Critical Animal and Media Studies approach is an unavoidable step forward for critical media and communication studies to engage with the expanded circle of concerns of contemporary ethical thinking

Prescribing practices of primary-care veterinary practitioners in dogs diagnosed with bacterial pyoderma

Concern has been raised regarding the potential contributions of veterinary antimicrobial use to increasing levels of resistance in bacteria critically important to human health. Canine pyoderma is a frequent, often recurrent diagnosis in pet dogs, usually attributable to secondary bacterial infection of the skin. Lesions can range in severity based on the location, total area and depth of tissue affected and antimicrobial therapy is recommended for resolution. This study aimed to describe patient signalment, disease characteristics and treatment prescribed in a large number of UK, primary-care canine pyoderma cases and to estimate pyoderma prevalence in the UK vet-visiting canine population

Elevated white cell count in acute coronary syndromes: relationship to variants in inflammatory and thrombotic genes

BACKGROUND: Elevated white blood cell counts (WBC) in acute coronary syndromes (ACS) increase the risk of recurrent events, but it is not known if this is exacerbated by pro-inflammatory factors. We sought to identify whether pro-inflammatory genetic variants contributed to alterations in WBC and C-reactive protein (CRP) in an ACS population. METHODS: WBC and genotype of interleukin 6 (IL-6 G-174C) and of interleukin-1 receptor antagonist (IL1RN intronic repeat polymorphism) were investigated in 732 Caucasian patients with ACS in the OPUS-TIMI-16 trial. Samples for measurement of WBC and inflammatory factors were taken at baseline, i.e. Within 72 hours of an acute myocardial infarction or an unstable angina event. RESULTS: An increased white blood cell count (WBC) was associated with an increased C-reactive protein (r = 0.23, p < 0.001) and there was also a positive correlation between levels of β-fibrinogen and C-reactive protein (r = 0.42, p < 0.0001). IL1RN and IL6 genotypes had no significant impact upon WBC. The difference in median WBC between the two homozygote IL6 genotypes was 0.21/mm(3 )(95% CI = -0.41, 0.77), and -0.03/mm(3 )(95% CI = -0.55, 0.86) for IL1RN. Moreover, the composite endpoint was not significantly affected by an interaction between WBC and the IL1 (p = 0.61) or IL6 (p = 0.48) genotype. CONCLUSIONS: Cytokine pro-inflammatory genetic variants do not influence the increased inflammatory profile of ACS patients

Circumstellar disks and planets. Science cases for next-generation optical/infrared long-baseline interferometers

We present a review of the interplay between the evolution of circumstellar disks and the formation of planets, both from the perspective of theoretical models and dedicated observations. Based on this, we identify and discuss fundamental questions concerning the formation and evolution of circumstellar disks and planets which can be addressed in the near future with optical and infrared long-baseline interferometers. Furthermore, the importance of complementary observations with long-baseline (sub)millimeter interferometers and high-sensitivity infrared observatories is outlined.Comment: 83 pages; Accepted for publication in "Astronomy and Astrophysics Review"; The final publication is available at http://www.springerlink.co

Sensitive Commercial NASBA Assay for the Detection of Respiratory Syncytial Virus in Clinical Specimen

The aim of the study was to evaluate the usability of three diagnostic procedures for the detection of respiratory syncytial virus in clinical samples. Therefore, the FDA cleared CE marked NOW® RSV ELISA, the NucliSENS® EasyQ RSV A+B NASBA, and a literature based inhouse RT-PCR protocol were compared for their relative sensitivities. Thereby, NASBA turned out to be the most sensitive method with a total number of 80 RSV positive samples out of a cohort of 251 nasopharyngeal washings from patients suffering from clinical symptoms, followed by the inhouse RT-PCR (62/251) and ELISA (52/251). Thus, NASBA may serve as a rapid and highly sensitive alternative for RSV diagnostics