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Theoretical analysis of the oscillating circular piston positive displacement flowmeter: II numerical solution of equations of motion and comparison with experimental data
In the first part of this paper we identified the forces and equations required to model the motion of the oscillating piston flowmeter. In this paper we discuss the method of solution, and the computational procedure for modelling the dynamic behaviour of the meter. We have, then, compared the model results with experimental data for variation in: angular velocity, vertical movement and pressure losses. We consider the agreement for variation in the following parameters: flow rate, piston mass, surface coating, lubrication holes, slots in piston skirt, length of up- and downstream pipe work, fluid viscosity and fluid density. We also compare the theory with data from two other sizes of meter. The predictions from the model are generally very accurate, although there is still potential to refine the model and increase further our understanding of the forces which contribute to the motion.EPSRC
Gatsby Charitable Foundatio
Metaplastic Conditions in The Bladder in Patient With Epidermolysis Bullosa
ABSTRACT Epidermolysis bullosa is a rare inherited muco-cutaneous disorder that sometimes presents with genitourinary involvement. Herein we report the case of an 11-year-old girl with a history of junctional epidermolysis bullosa who was admitted with urological symptoms. On cystoscopy, suspected bullous bladder lesions were observed. Mesonephroid, intestinal and squamous metaplasia is reported here for the first time
The horseracing industry’s perception of nutritional and weight-making practices of professional jockeys
The present paper provides a qualitative study exploring perceptions of nutritional and weight-making practices of professional jockeys, as reported by key industry stakeholders. Semi-structured interviews were conducted with 26 participants, including professional jockeys (n = 10), racecourse clerks (n = 7), jockey agents (n = 2), racehorse trainers (n = 3) and jockey coaches (n = 4). Via thematic analysis, data provided an insight into the industry-specific factors influencing current nutrition practices amongst jockeys. A perceived lack of industry-wide nutrition education, combined with conflicting views over the recognition of jockeys as athletes act as barriers to optimal nutrition and wellbeing support associated with other sports. The development of an industry-specific education platform for jockeys would equip them with the knowledge to make independently informed choices and the applied skills to implement better nutrition strategies, in the absence of industry support
Perspectives on the role of nutrition in influencing academy soccer player development and performance: A qualitative case study of key stakeholders from an English category one soccer academy
This study aimed to explore player and stakeholder perceptions of the role of nutrition in influencing the development of male academy soccer players. Semi-structured interviews (28 ± 13 mins in length) were conducted with 31 participants from an English category one academy, including players (Youth Development Phase, YDP: n = 6; Professional Development Phase, PDP: n = 4), parents/guardians (n = 10), coaches (n = 3), sport scientists (n = 3), physiotherapists (n = 3), and catering (n = 2). Via reflexive thematic analysis, data demonstrate an apparent lack of understanding and awareness on the role of nutrition in influencing player development, especially in relation to growth, maturation and reducing injury risk. Players highlighted the influence of their parents on their dietary behaviours, whilst parents also called for education to better support their sons. Notably, players and stakeholders perceived that the daily schedule of an academy soccer player presents as “too busy to eat”, especially in relation to before school, and before and after training. The results demonstrate the necessity for the co-creation of player and stakeholder specific nutrition education programmes as an initial step towards positively impacting the nutrition culture associated with the academy soccer environment
Bayesian estimates of linkage disequilibrium
[Background]
The maximum likelihood estimator of D' – a standard measure of linkage disequilibrium – is biased toward disequilibrium, and the bias is particularly evident in small samples and rare haplotypes.
[Results]
This paper proposes a Bayesian estimation of D' to address this problem. The reduction of the bias is achieved by using a prior distribution on the pair-wise associations between single nucleotide polymorphisms (SNP)s that increases the likelihood of equilibrium with increasing physical distances between pairs of SNPs. We show how to compute the Bayesian estimate using a stochastic estimation based on MCMC methods, and also propose a numerical approximation to the Bayesian estimates that can be used to estimate patterns of LD in large datasets of SNPs.
[Conclusion]
Our Bayesian estimator of D' corrects the bias toward disequilibrium that affects the maximum likelihood estimator. A consequence of this feature is a more objective view about the extent of linkage disequilibrium in the human genome, and a more realistic number of tagging SNPs to fully exploit the power of genome wide association studies.Research supported by NIH/NHLBI grant R21 HL080463-01, NIH/NIDDK 1R01DK069646-01A1 and the Spanish research program [projects TIN2004-06204-C03-02 and TIN2005-02516]
An audit of performance nutrition services in English soccer academies: implications for optimising player development
To audit the current provision of performance nutrition services provided to male adolescent players within academies from the English soccer leagues. Practitioners from all 89 academies (status categorised as one-four according to the Elite Player Performance Plan, EPPP) completed an online survey to audit: a) job role/professional accreditation status of persons delivering nutrition support, b) activities inherent to service provision, c) topics of education, d) on-site food, fluid and supplement provision and e) nutritional related data collected for objective monitoring. More full-time accredited nutritionists are employed within category one (14/26) versus category two (0/18), three (1/41) and four (0/4). Respondents from category one clubs report more hours of monthly service delivery (62 ± 57 h) than category two (12 ± 9 h), three (14 ± 26 h) and four (12 ± 14 h), inclusive of one-to-one player support and stakeholder education programmes. Category one practitioners reported a greater prevalence of on-site food, fluid and supplement provision on training and match days. Across all categories, players from the professional development phase receive more frequent support than players from the youth development phase, despite the latter corresponding to the most rapid phase of growth and maturation. We report distinct differences in the extent of service provision provided between categories. Additionally, players from all categories receive nutrition support from non-specialist staff. Data demonstrate that performance nutrition appears an under-resourced component of academy sport science and medicine programmes in England, despite being an integral component of player development
A [4Fe-4S]-Fe(CO)(CN)-L-cysteine intermediate is the first organometallic precursor in [FeFe] hydrogenase H-cluster bioassembly.
Biosynthesis of the [FeFe] hydrogenase active site (the 'H-cluster') requires the interplay of multiple proteins and small molecules. Among them, the radical S-adenosylmethionine enzyme HydG, a tyrosine lyase, has been proposed to generate a complex that contains an Fe(CO)2(CN) moiety that is eventually incorporated into the H-cluster. Here we describe the characterization of an intermediate in the HydG reaction: a [4Fe-4S][(Cys)Fe(CO)(CN)] species, 'Complex A', in which a CO, a CN- and a cysteine (Cys) molecule bind to the unique 'dangler' Fe site of the auxiliary [5Fe-4S] cluster of HydG. The identification of this intermediate-the first organometallic precursor to the H-cluster-validates the previously hypothesized HydG reaction cycle and provides a basis for elucidating the biosynthetic origin of other moieties of the H-cluster
Performance Nutrition in the Digital Era – An exploratory study into the use of Social Media by Sports Nutritionists
This study aimed to explore how social media is being used by sports nutritionists as part of service provision, as well as practitioners’ experiences and opinions of its use in practice. An exploratory sequential mixed methods approach was used during this research. Forty-four sports nutritionists completed an online survey detailing their personal and professional social media use. Semi-structured follow-up interviews were conducted with 16 participants who volunteered to do so. Survey responses were collated and reported as descriptive statistics. Interviews were thematically analysed.
Social media was used by 89% of sports nutritionists to support practice, of which 97% perceived its use to be beneficial. Platforms were used to deliver information and resources, and support athletes online via pages, groups and 1-2-1 messaging. Social media facilitated improved communication between the practitioner and the athlete, as well as facilitating mobile and visual learning. Lack of digital intervention training and time were reported as challenges to social media use in practice.
Sports nutritionists have embraced social media as an extension of service provision. Professional education should now consider supporting nutritionists’ in developing digital professionalism
In vitro growth environment produces lipidomic and electron transport chain abnormalities in mitochondria from non-tumorigenic astrocytes and brain tumours
The mitochondrial lipidome influences ETC (electron transport chain) and cellular bioenergetic efficiency. Brain tumours are largely dependent on glycolysis for energy due to defects in mitochondria and oxidative phosphorylation. In the present study, we used shotgun lipidomics to compare the lipidome in highly purified mitochondria isolated from normal brain, from brain tumour tissue, from cultured tumour cells and from non-tumorigenic astrocytes. The tumours included the CT-2A astrocytoma and an EPEN (ependymoblastoma), both syngeneic with the C57BL/6J (B6) mouse strain. The mitochondrial lipidome in cultured CT-2A and EPEN tumour cells were compared with those in cultured astrocytes and in solid tumours grown in vivo. Major differences were found between normal tissue and tumour tissue and between in vivo and in vitro growth environments for the content or composition of ethanolamine glycerophospholipids, phosphatidylglycerol and cardiolipin. The mitochondrial lipid abnormalities in solid tumours and in cultured cells were associated with reductions in multiple ETC activities, especially Complex I. The in vitro growth environment produced lipid and ETC abnormalities in cultured non-tumorigenic astrocytes that were similar to those associated with tumorigenicity. It appears that the culture environment obscures the boundaries of the Crabtree and the Warburg effects. These results indicate that in vitro growth environments can produce abnormalities in mitochondrial lipids and ETC activities, thus contributing to a dependency on glycolysis for ATP production
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