5,502 research outputs found

    Centrifugally Spun PHBV Micro and Nanofibres

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    This paper reports the first study on centrifugal spinning of PHBV fibres. Fibres were spun from solution using a range of polymer concentrations, spin speeds and spinneret to collector distances. A PHBV polymer concentration of 25% w/v spun at 9000 r min⁻¹ produced the highest quality fibres, with fibre diameters predominantly in the 0.5-3 μm range. The rate at which fibre could be produced at the 9000 r min‾¹ spin speed and with a spinneret to collector distance of 39.2 cm was equivalent to 11 km of fibre per minute per needle. Average fibre strengths of 3 MPa were achieved, together with average moduli of 100 MPa, indicating that the fibres had higher strength but lower stiffness than electrospun PHBV. The productivity and mechanical properties achieved, together with the excellent biocompatibility of PHBV, means that these fibres have potential for application in a range of biomedical applications

    Controlling dielectric and magnetic properties of PVdF/Magnetite nanocomposite fibre webs.

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    The ability of filtration and separation media containing fibres to remove impurities from oil, water, and blood can be enhanced using magnetic fields. The ability to regulate the dielectric and magnetic behaviour of fibrous webs in terms of superparamagnetic or ferromagnetic properties by adjusting material composition is fundamental to meeting end-use requirements. Electrospun fibres were produced from PVdF (polyvinylidene fluoride) and nanomagnetite (Fe3O4 nanoparticles) from solutions of PVdF in dimethylacetamide containing Fe3O4 nanoparticle contents ranging from 3 to 10 wt%. Fibre dimensions, morphology, and nanoparticle agglomeration were characterised by environmental scanning electron microscopy (ESEM) and field emission gun transmission electron microscopy (FEGTEM). Dielectric behaviour of the fibre webs was influenced by web porosity and the Fe3O4 nanoparticle content. Impedance analysis of the webs indicated an increase in dielectric constant of ∼80% by the addition of 10 wt% Fe3O4 nanoparticles compared to 100 wt% PVdF. The dielectric constants of the webs were compared with those obtained from the theoretical mixing models of Maxwell and Lichtenecker. Vibrating sample magnetometer (VSM) magnetisation measurements indicated a blocking temperature above 300 K suggesting ferrimagnetic rather than superparamagnetic behaviour as a result of Fe3O4 nanoparticle agglomeration within fibres

    Impact of childhood experience and adult well-being on eating preferences and behaviours

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    OBJECTIVES: To examine the relative contribution of childhood experience, measured by childhood violence and childhood happiness, and adult well-being on adult eating preferences and behaviours, independent of proximal factors such as current deprivation. DESIGN: A cross-sectional, stratified, randomised sample survey using retrospective measures of childhood violence and happiness and self-reported measures of current well-being. SETTING: The North West Region of England between September 2012 and March 2013. PARTICIPANTS: Individuals aged 18–95-year-olds from randomly selected households (participation was successful for 90% of eligible households and 78% of the total visited addresses; n=11 243). OUTCOMES: Dichotomised measures for preference of healthy foods or ‘feel good’ foods and low or high daily fruit and vegetable consumption. RESULTS: After correcting for demographics, combined categories for childhood experience and dichotomised measures of adult well-being were found to be significantly related to adult food preferences and eating behaviours. Participants with unhappy and violent childhoods compared to those with happy and non-violent childhoods had adjusted ORs (95% CI, significance) of 2.67 (2.15 to 3.06, p<0.001) of having low daily fruit and vegetable intake (two or less portions) and 1.53 (1.29 to 1.81, p<0.001) of choosing ‘feel good’ foods over foods which were good for their long term health. CONCLUSIONS: Daily intake of fruit and vegetables, linked to non-communicable diseases, and preference for ‘feel good’ foods, linked to obesity, are affected by childhood experience and adult well-being independent of demographic factors. Preventative interventions which support parent–child relationships and improve childhood experience are likely to reduce the development of poor dietary and other health-risk behaviours

    Falls across Lancashire (April 2013 to March 2016)

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    Falls are the second leading cause of death from accidents worldwide and adults aged over 65 years suffer the greatest number of fatal falls. Between April 2013 and March 2016, there were 63,398 ambulance call outs and 17,182 emergency hospital admissions for falls in Lancashire. This TIIG Lancashire report presents data and analyses relating to ambulance call outs and emergency hospital admissions for falls using North West Ambulance Service (NWAS) and Hospital Episodes Statistics (HES) data. Trends are presented in terms of demographics, call out locations and patient geography. Comparisons are also drawn between NWAS and HES data, particularly in terms of age standardised rates per 1,000 population for given geographical areas

    Location of violent incidents across Lancashire (April 2013 to March 2016)

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    Violence is a preventable public health problem and yet there are over one million violent incidents each year in England and Wales, approximately half of which involve alcohol and one-quarter of which occur in night-time economy environments. Between April 2013 and March 2016 there were 14,427 attendances to Lancashire Emergency Departments (EDs) by residents of Lancashire for injuries sustained from violence. This TIIG Lancashire report presents data and analyses relating to the locations of violence, specifically in terms of patient area of residence, as determined by ED data, and ambulance call out location, as determined by North West Ambulance Service (NWAS) data. Trends are also presented in terms of geographic compositions of assault ED attendances/ambulance call outs, deprivation and, in terms of ED data, incident location categories and attendance details. Analyses also compare ED data (patient geography) with NWAS data (location geography), particularly in terms of attendance/call out numbers and rates by local/unitary authority areas and lower super output areas

    Identifying at-risk groups in Lancashire (April 2012 to March 2015)

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    TIIG Cumbria overview report: Emergency Department data collection and overview (April 2012 to March 2015)

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    Reducing intentional and unintentional injuries is a key objective of Cumbria County Council and public health professionals, service providers and other organisations that make up Community Safety Partnerships (CSPs) within Cumbria. Emergency Departments (EDs) can play a central and leading role, not only in providing rich and timely data, but in providing objective and informed recommendations for targeted prevention measures and interventions. This Trauma and Injury Intelligence Group (TIIG) themed report presents an overview of unintentional and intentional injuries in Cumbria, primarily using ED recorded data between April 2012 and March 2015. Data are discussed within the context of demographic trends and socioeconomic factors, including levels of deprivation. While ED data collection is generally excellent in Cumbria, there are several areas where data collection and quality may be improved. This report discusses these key data issues with particular focus on injury groups and enhanced assault information

    Integrity Monitoring of Pressurized Gas Cylinders Using the SSUE Technique

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    Spread-Spectrum Ultrasonic Evaluation (SSUE) is a newly emerging technique for the global inspection and integrity monitoring of objects such as pressurized gas cylinders and structures such as bridges and airframes. This technique is based upon the measurement of an ultrasonic correlation signature which is sensitive to the structural and material properties of the test object. Recently, we applied the technique to pressurized gas cylinders and found that it was very sensitive to small changes in the cylinder. Specifically, we looked at the ability of the SSUE method to detect artificially-induced cracks at various points on the outside of the cylinder
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