Perceptions and current practice vs evidence-based effects of whole-body cryotherapy on fatigue and recovery in elite rugby players.

The primary aim of this thesis was to advance the current field of knowledge regarding whole-body cryotherapy (WBC) and its influence on fatigue and recovery in elite rugby players. The secondary aim of this thesis was to explore the perceptions and current use of WBC in an elite contact sport population. A systematic review analysed fifteen studies specific to the use of WBC following fatiguing physical activity. Despite the body of evidence reflecting low-to-moderate quality, WBC appears to result in perceived and symptomatic benefits, with some indications of positive change to recovery via physiological and inflammatory measures. Endocrinological responses were shown to be vastly under-researched and required clarification. A qualitative survey formed the basis of exploring the beliefs and perceptions of fatigue, recovery and current practice of WBC within elite contact sport environments. The key findings highlighted that (i) recovery from evening match or training activity was frequently impacted due to reduced perceived sleep quality; (ii) the perceived benefits of WBC enhanced sleep quality for those who had experienced WBC; (iii) the beliefs of those who had not experienced WBC was that they would highly likely adopt its use on the basis that sleep quality and psychological wellbeing would be enhanced in order to benefit recovery; (iv) the adoption of WBC as a regular practice-based modality for recovery is low mainly due to cost, logistics and lack of evidence-based information supporting parameters of implementation. Two experimental, field-based studies were conducted using an elite Rugby League team from the European Super League. The first was an observational study and had the purpose of analysing the endocrinological (cortisol and testosterone) responses to a nine-day period of competition involving match and training activity and regular WBC exposures. These have been shown to be reliable indicators of catabolic and anabolic basal control in response to high intensity physical activity. The use of WBC post-training appeared to attenuate anabolic status, whereas following matches, anabolic signaling was enhanced following WBC. The second study was a participant controlled design comparing post-match recovery inclusive of WBC to regular recovery processes without WBC. Two, three-minute exposures to WBC showed significant alteration to the endocrine profile of players at 60 h post-match in that greater concentrations of testosterone were found without concurrent change in cortisol. A significant effect was shown after one exposure to WBC, albeit to a lesser degree. Without WBC, the recovery of endocrine and biochemical profile was not reached by the end of the 60-h sample period. In summary, this thesis supports the use of WBC in that it appears to hold benefits for athletes in their recovery from elite level collision sport. Greater benefits appear more supported following matches, with a lesser extent, post-training sessions. Medical practitioners, coaches and sport scientists/conditioners should look to optimise the influence of WBC though applying two, 3-minute exposures as close to the cessation of high-fatiguing activity as possible. WBC has the potential to improve the wellbeing and recovery of collision sport athletes, however, the underlying mechanisms involved remain undetermined despite the observation of a desirable change in endocrinological profile. Further study should look to specifically investigate the effects of WBC relative to the time of day of activity given that indications in this study from a perceived perspective suggest that effects may be relative to activity and time of day. This area currently holds negligible supporting evidence and will assist to inform the implementation strategy of WBC in the team environment

Livestock disease management for trading across different regulatory regimes

The maintenance of livestock health depends on the combined actions of many different actors, both within and across different regulatory frameworks. Prior work recognised that private risk management choices have the ability to reduce the spread of infection to trading partners. We evaluate the efficiency of farmers' alternative biosecurity choices in terms of their own-benefits from unilateral strategies and quantify the impact they may have in filtering the disease externality of trade. We use bovine viral diarrhoea (BVD) in England and Scotland as a case study, since this provides an example of a situation where contrasting strategies for BVD management occur between selling and purchasing farms. We use an agent-based bioeconomic model to assess the payoff dependence of farmers connected by trade but using different BVD management strategies. We compare three disease management actions: test-cull, test-cull with vaccination and vaccination alone. For a two-farm trading situation, all actions carried out by the selling farm provide substantial benefits to the purchasing farm in terms of disease avoided, with the greatest benefit resulting from test-culling with vaccination on the selling farm. Likewise, unilateral disease strategies by purchasers can be effective in reducing disease risks created through trade. We conclude that regulation needs to balance the trade-off between private gains from those bearing the disease management costs and the positive spillover effects on others

Modelling the Impact and Control of an Infectious Disease in a Plant Nursery with Infected Plant Material Inputs

The ornamental plant trade has been identified as a key introduction pathway for plant pathogens. Establishing effective biosecurity measures to reduce the risk of plant pathogen outbreaks in the live plant trade is therefore important. Management of invasive pathogens has been identified as a weakest link public good, and thus is reliant on the actions of individual private agents. This paper therefore provides an analysis of the impact of the private agents’ biosecurity decisions on pathogen prevention and control within the plant trade. We model the impact that an infectious disease has on a plant nursery under a constant pressure of potentially infected input plant materials, like seeds and saplings, where the spread of the disease reduces the value of mature plants. We explore six scenarios to understand the influence of three key bioeconomic parameters; the disease’s basic reproductive number, the loss in value of a mature plant from acquiring an infection and the cost-effectiveness of restriction. The results characterise the disease dynamics within the nursery and explore the trade-offs and synergies between the optimal level of efforts on restriction strategies (actions to prevent buying infected inputs), and on removal of infected plants in the nursery. For diseases that can be easily controlled, restriction and removal are substitutable strategies. In contrast, for highly infectious diseases, restriction and removal are often found to be complementary, provided that restriction is cost-effective and the optimal level of removal is non-zero

An angle-scanned cryogenic Fabry-Pérot interferometer for far-infrared astronomy

The sensitivity of state-of-the-art superconducting far-infrared detectors used in conjunction with cryogenically cooled space telescopes and instrumentation is such that spectroscopic observations are generally limited by photon noise from the astronomical source or by galactic foreground or zodiacal emission within the field-of-view. Therefore, an instrument design that restricts the spectral bandpass viewed by the detector must be employed. One method of achieving background limited, high resolution spectroscopy is to combine a high resolution component such as a Fabry–Pérot interferometer (FPI) with a lower resolution, post-dispersing system, such as a grating spectrometer, the latter serving to restrict the spectral bandpass. The resonant wavelength of an FPI is most often tuned by changing the spacing or medium between the parallel reflecting plates of the etalon. In this paper, we present a novel design for an FPI in which the wavelength is tuned by scanning the angle of incidence on a high refractive index etalon. This concept simplifies the cryomechanical design, actuation, and metrology. The first results from the realized instrument are presented and compared with theory. The effects on the spectral response as a function of the incident angle have been simulated and shown to agree well with the observation

Shaping landscapes and industry: linking historic watermill locations to bedrock river knickpoints

Watermills have been an essential source of mechanical power for over two millennia. Their careful siting often took into account local hydrology, topography, and economic demand, attesting to the important place they held in premodern and early modern societies. This paper highlights the significance of Paul Bishop's work on mills over the last 20 years, which revealed that numerous historical watermills along Scottish rivers were closely located near overly steep stretches of river to maximize waterpower and minimize cost. Termed ‘knickpoints’, many of these steep erosional features formed thousands of years ago during and after melting of the British–Irish Ice Sheet. Post-glacial isostatic rebound caused rivers to erode into bedrock at rates set by river catchment size and sediment availability. Although bedrock knickpoints along the Scottish coast are relatively stable over human timescales (<103 years), knickpoints generated by milling in England have been invoked as potential hazards due to their potential to migrate over similar timescales. Bishop's observations on the colocation of knickpoints and watermills encouraged a more comprehensive investigation of the relationship between natural and human systems over the last 250 years and invited re-evaluation of prevailing narratives for the history of water technology and patterns of water-powered industrialization in Britain

Development and validation of a cryogenic far-infrared diffraction grating spectrometer used to post-disperse the output from a Fourier transform spectrometer

Recent advances in far-infrared detector technology have led to increases in raw sensitivity of more than an order of magnitude over previous state-of-the-art detectors. With such sensitivity, photon noise becomes the dominant noise component, even when using cryogenically cooled optics, unless a method of restricting the spectral bandpass is employed. The leading instrument concept features reflecting diffraction gratings, which post-disperse the light that has been modulated by a polarizing Fourier transform spectrometer (FTS) onto a detector array, thereby reducing the photon noise on each detector. This paper discusses the development of a cryogenic (4 K) diffraction grating spectrometer that operates over the wavelength range of 285 to 500 μm and was used to post-disperse the output from a room-temperature polarizing FTS. Measurements of the grating spectral response and diffraction efficiency are presented as a function of both wavelength and polarization to characterize the instrumental performance

First light results from a novel cryogenic Fabry-Pérot interferometer

The sensitivity of state-of-the-art superconducting far-infrared detectors is such that astronomical observations at these wavelengths are limited by photon noise from the astronomical source unless a method of restricting the spectral bandpass is employed. One such method is to use a high resolution Fabry-Perot interferometer (FPI) in conjunction with a lower resolution, post-dispersing system, such as a grating spectrometer. The resonant wavelength of an FPI is typically tuned by changing the spacing or medium between the parallel reflecting plates of the etalon. We previously reported on a novel design in which the wavelength is tuned by scanning the angle of incidence, which simplifies the cryo-mechanical design, actuation and metrology. Here we present first light results from the realized instrument

Genetic Deletion of the Stromal Cell Marker CD248 (Endosialin) Protects against the Development of Renal Fibrosis

BACKGROUND: Tissue fibrosis and microvascular rarefaction are hallmarks of progressive renal disease. CD248 is a transmembrane glycoprotein expressed by key effector cells within the stroma of fibrotic kidneys including pericytes, myofibroblasts and stromal fibroblasts. In human disease, increased expression of CD248 by stromal cells predicts progression to end-stage renal failure. We therefore, hypothesized that the genetic deletion of the CD248 gene would protect against fibrosis following kidney injury. METHODS: Using the unilateral ureteral obstruction (UUO) model of renal fibrosis, we investigated the effect of genetic deletion of CD248 on post obstructive kidney fibrosis. RESULTS: CD248 null mice were protected from fibrosis and microvascular rarefaction following UUO. Although the precise mechanism is not known, this may to be due to a stabilizing effect of pericytes with less migration and differentiation of pericytes toward a myofibroblast phenotype in CD248(-/-) mice. CD248(-/-) fibroblasts also proliferated less and deposited less collagen in vitro. CONCLUSION: These studies suggest that CD248 stromal cells have a pathogenic role in renal fibrosis and that targeting CD248 is effective at inhibiting both microvascular rarefaction and renal fibrosis through modulation of pericyte and stromal cell function