932 research outputs found
Sort by
Hyperspectral chemical imaging reveals spatially varied degradation of polycarbonate urethane (PCU) biomaterials
Get PDFHyperspectral chemical imaging (HCI) is an emerging technique which combines spectroscopy with imaging. Unlike traditional point spectroscopy, which is used in the majority of polymer biomaterial degradation studies, HCI enables the acquisition of spatially localised spectra across the surface of a material in an objective manner. Here, we demonstrate that attenuated total reflectance Fourier transform infra-red (ATR-FTIR) HCI reveals spatial variation in the degradation of implantable polycarbonate urethane (PCU) biomaterials. It is also shown that HCI can detect possible defects in biomaterial formulation or specimen production; these spatially resolved images reveal regional or scattered spatial heterogeneity. Further, we demonstrate a map sampling method, which can be used in time-sensitive scenarios, allowing for the investigation of degradation across a larger component or component area. Unlike imaging, mapping does not produce a contiguous image, yet grants an insight into the spatial heterogeneity of the biomaterial across a larger area. These novel applications of HCI demonstrate its ability to assist in the detection of defective manufacturing components and lead to a deeper understanding of how a biomaterial’s chemical structure changes due to implantation.
Statement of Signifance
The human body is an aggressive environment for implantable devices and their biomaterial components. Polycarbonate urethane (PCU) biomaterials in particular were investigated in this study. Traditionally one or a few points on the PCU surface are analysed using ATR-FTIR spectroscopy. However the selection of acquisition points is susceptible to operator bias and critical information can be lost. This study utilises hyperspectral chemical imaging (HCI) to demonstrate that the degradation of a biomaterial varies spatially. Further, HCI revealed spatial variations of biomaterials that were not subjected to oxidative degradation leading to the possibility of HCI being used in the assessment of biomaterial formulation and/or component production
TET-2 up-regulation is associated with the anti-inflammatory action of Vicenin-2
Get PDFVicenin-2, a C-glycoside flavone that is present in many plant sources, exerts potent anti-inflammatory effects in a number of cell and animal models of inflammation. Ten-eleven translocation (TET)-2 has recently gained considerable attention due to the role it plays in regulating the inflammasome. We studied the ability of Vicenin-2 (V-2) to regulate a range of lipopolysaccharide (LPS) stimulated inflammatory activities in PMA-differentiated THP-1 cells and human primary mononuclear cells. We also investigated the action of V-2 on the secretion of NLRP3 inflammasome regulated cytokines (IL-1β and IL-18) by ELISA, and determined if V-2 can regulate the expression of NLRP3, IL-10, IL-1Ra and TET-2. The effect of V-2 on NF-κB signalling was investigated by fluorescence microscopy and gene reporter assay. Additionally, the effect of V-2 on LPS-induced phosphorylation of IKB-α was also investigated by Western blot analysis.
V-2 down-regulated LPS-induced secretion of proinflammatory cytokines (TNF-α and IL-1β), in both THP-1 and primary mononuclear cells. V-2 also decreased the LPS-stimulated secretion of IL-18 in THP-1 cells. V-2 significantly down-regulated TNF-α induced NF-κB reporter activity in HEK293T transfected cells and attenuated IKB-α phosphorylation in THP-1 cells. V-2 treatment also induced enhanced nuclear staining of the p50 subunit and reduced p65 subunit of NF-κB.
V-2 treatment alone increased the expression of anti-inflammatory cytokine, IL-10, and the regulator of the inflammasome; IL-1Ra, in the presence of LPS. V-2 also significantly decreased LPS-induced NLRP3 expression while concomitantly increasing TET-2 expression.
This study demonstrates that the anti-inflammatory actions of V-2 are associated not only with increased IL-10 and IL-1Ra expression, but also with TET-2 up-regulation. Further work is required to establish if the effects of V-2 can be definitively linked to TET-2 activity and that these actions are mirrored in a range of relevant cell types
A Technical Skill Training Framework and Skill Load Measurements for the Rugby Union Tackle
Get PDFDrawing from skill acquisition and development literature, we present a novel tackle skill training framework. The framework outlines the training purpose (technique proficiency, technique capacity, skill proficiency and skill capacity), skill workload measurements (available information, task difficulty, rating of perceived challenge, skill load), as well as the training conditions and coaching style for the tackle in rugby union. Using this framework and skill load measurements, we propose a pre-season tackle training plan. This tackle skill framework and skill load measurements serve as potential preventive measures for tackle injury risk while improving players’ tackle performance
May Measurement Month 2017: an analysis of blood pressure screening results worldwide
Get PDFBackground
Increased blood pressure is the biggest contributor to the global burden of disease and mortality. Data suggest that less than half of the population with hypertension is aware of it. May Measurement Month was initiated to raise awareness of the importance of blood pressure and as a pragmatic interim solution to the shortfall in screening programmes.
Methods
This cross-sectional survey included volunteer adults (≥18 years) who ideally had not had their blood pressures measured in the past year. Each participant had their blood pressure measured three times and received a a questionnaire about demographic, lifestyle, and environmental factors. The primary objective was to raise awareness of blood pressure, measured by number of countries involved, number of people screened, and number of people who have untreated or inadequately treated hypertension (defined as systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg, or both, or on the basis of receiving antihypertensive medication). Multiple imputation was used to estimate the mean of the second and third blood pressure readings if these were not recorded. Measures of association were analysed using linear mixed models.
Findings
Data were collected from 1 201 570 individuals in 80 countries. After imputation, of the 1 128 635 individuals for whom a mean of the second and third readings was available, 393 924 (34·9%) individuals had hypertension. 153 905 (17·3%) of 888 616 individuals who were not receiving antihypertensive treatment were hypertensive, and 105 456 (46·3%) of the 227 721 individuals receiving treatment did not have controlled blood pressure. Significant differences in adjusted blood pressures and hypertension prevalence were apparent between regions. Adjusted blood pressure was higher in association with antihypertensive medication, diabetes, cerebrovascular disease, smoking, and alcohol consumption. Blood pressure was higher when measured on the right arm than on the left arm, and blood pressure was highest on Saturdays.
Interpretation
Inexpensive global screening of blood pressure is achievable using volunteers and convenience sampling. Pending the set-up of systematic surveillance systems worldwide, MMM will be repeated annually to raise awareness of blood pressure
The design of additively manufactured lattices to increase the functionality of medical implants
Get PDFThe rise of antibiotic resistant bacterial species is driving the requirement for medical devices that minimise infection risks. Antimicrobial functionality may be achieved by modifying the implant design to incorporate a reservoir that locally releases a therapeutic. For this approach to be successful it is critical that mechanical functionality of the implant is maintained. This study explores the opportunity to exploit the design flexibilities possible using additive manufacturing to develop porous lattices that maximise the volume available for drug loading while maintaining load-bearing capacity of a hip implant.
Eight unit cell types were initially investigated and a volume fraction of 30% was identified as the lowest level at which all lattices met the design criteria in ISO 13314. Finite element analysis (FEA) identified three lattice types that exhibited significantly lower displacement (10-fold) compared with other designs; Schwartz primitive, Schwartz primitive pinched and cylinder grid. These lattices were additively manufactured in Ti-6Al-4V using selective laser melting. Each design exceeded the minimum strength requirements for orthopaedic hip implants according to ISO 7206-4. The Schwartz primitive (Pinched) lattice geometry, with 10% volume fill and a cubic unit cell period of 10, allowed the greatest void volume of all lattice designs whilst meeting the fatigue requirements for use in an orthopaedic implant (ISO 7206-4). This paper demonstrates an example of how additive manufacture may be exploited to add additional functionality to medical implants
Pupils’ Expectations and Experiences of PE across the Primary–secondary Transition in South Wales
Get PDFThis paper explores the experiences of physical education (PE) among a group of 10–11-year-old pupils who made the transition to an inner-city secondary school in south Wales from one of its feeder primary schools during 2013. The primary–secondary transition concerning PE is marked by significant changes in resource provision, and a mode of delivery from (mainly) non-specialist teachers to subject specialists (Capel and Piotrowski, 2000). Identified as a source of discontinuity at a time of potential risk, the impact of PE has been neglected with educational research (Dismore and Bailey, 2010). As a qualitative exploratory study, an ethnographic approach was adopted with 'pupil voice' a distinctive and central feature. Two six-week phases of fieldwork were conducted which examined the holistic impact of PE across transition in a secondary school and its feeder primary school (June–October 2013). Twenty-five pupils' expectations and experiences of PE across the transition were explored: first prior to transition (primary school) and then post-transition (secondary school). Thematic analysis of pupil interviews, staff interviews and classroom drawings was conducted and created three super ordinate findings which relate to pupils' perception of the process of transition and specifically in terms of PE; the notion of 'being good enough'; social implications of transition and gender; teachers and teaching were all highlighted as significant issues across the transitional process
Transition from Primary to Secondary School and More Able and Talented (MAT) Disadvantaged Pupils: Evidence from South-east Wales
Get PDFIn Wales, as in many other education systems, there is an increasing focus on the impact that poverty can have on the educational achievement of disadvantaged pupils. Educational research in this area has included a focus on boys (compared to girls), ethnic minority groups and those with additional learning needs. Little attention, however, has been paid to pupils from disadvantaged backgrounds who have been identified as being more able and talented (MAT). This article reports on a mixed-method research evaluation of such pupils in a sample of schools in south-east Wales in relation to the impact of their transition from primary to secondary education. The findings from the research highlight variations in the definition and identification of MAT learners between primary and secondary schools and a lack of attention to this specific group of learners in school transition plans and policies. This leads the researchers to argue for the need for schools to specifically identify this group of pupils through the transition process and to suggest specific areas where transition practice might be strengthened to cater for their needs. The study supports the limited research that has been undertaken in this area that specific groups of more vulnerable pupils, such as those who are MAT but come from disadvantaged backgrounds, may suffer from shortcomings in the primary to secondary transition process such that it hampers their progression and the realisation of their potential
Intangible Cultural Heritage Beyond Borders: Egyptian Bellydance (Raqs Sharqi) as a Form of Transcultural Heritage
Get PDFThe 2003 UNESCO Convention on Intangible Cultural Heritage highlights the importance of safeguarding traditional practices. While some of these practices are only performed in their place of origin, others (such as yoga and flamenco) take place worldwide. In this paper we explore what happens when a form of ICH that originated in one place becomes global. For this, we use Egyptian raqs sharqi (bellydance) as a case study. This is a dance genre with strong cultural roots in Egypt but is also hybrid and now practiced worldwide. Theoretically, we draw on a holistic view of living heritage, Welsch's transculturality and Urry's mobilities. Research methods include one-to-one interviews, analysis of written sources and of online dance videos. Raqs sharqi emerges as hybrid and transcultural, yet strongly connected to Egypt as the origin of its heritage. We conclude that ICH can be transcultural and global, whilst maintaining a strong connection to its place of origin
Non-state nations: Structure, rescaling, and the role of territorial policy communities, illustrated by the cases of Wales and Sardinia
Get PDFThis paper explores the role of non-state nations’ identity and agency with regard to relations with their host nation states. The particular focus here is on the means by which such regions might express their individuality. To this end, we employ a comparative case study analysis of two non-state nations with a range of differing yet in other ways similar qualities – namely Wales (UK) and Sardinia (Italy). We suggest that this is a valuable exercise, allowing as it does for the exploring of evidence ‘on the ground’ of the processes involved. The conceptual rationale for the paper is provided by new regionalism – regions as actors beyond the nation state. Following this, the idea of the ‘territorial policy community’ is presented as a point of departure, with the scope of the paper being to develop a diachronic framework for regional change. Given the focus on identity and interest articulation, the role of regional political parties is a particular subject of the empirical investigation, with non-state nations and nation states linked by opportunistic relationships based on political and electoral support. We then consider what this might mean with regard to the capacity of non-state nations to build on the past to successfully negotiate future policy-making agendas. Finally, we reflect on the limitations of the study, and consider the implications of its findings for further research agendas
Differences in step characteristics and linear kinematics between rugby players and sprinters during initial sprint acceleration
Get PDFThe initial steps of a sprint are important in team sports, such as rugby, where there is an inherent requirement to maximally accelerate over short distances. Current understanding of sprint acceleration technique is primarily based on data from track and field sprinters, although whether this information is transferable to athletes such as rugby players is unclear, due to differing ecological constraints. Sagittal plane video data were collected (240 Hz) and manually digitised to calculate the kinematics of professional rugby forwards (n = 15) and backs (n = 15), and sprinters (n = 18; 100 m personal best range = 9.96–11.33 s) during the first three steps of three maximal sprint accelerations. Using a between-group research design, differences between groups were determined using magnitude-based inferences, and within-group relationships between technique variables and initial sprint acceleration performance were established using correlation. Substantial between-group differences were observed in multiple variables. Only one variable, toe-off distance, differed between groups (d = −0.42 to −2.62) and also demonstrated meaningful relationships with sprint performance within all three groups (r = −0.44 to −0.58), whereby a stance foot position more posterior relative to the centre of mass at toe-off was associated with better sprint performance. While toe-off distance appears to be an important technical feature for sprint acceleration performance in both sprinters and rugby players, caution should be applied to the direct transfer of other kinematic information from sprinters to inform the technical development of acceleration in team sports athletes