358 research outputs found

    Overcoming fears: a pathway to publishing for early career researchers

    Get PDF
    Purpose – The purpose of this paper is to present reflections of five early career researchers on the challenges of journal publishing and how to tackle them. Design/methodology/approach – The authors attended a participatory workshop on demystifying academic publications. Working individually and in groups the authors shared, discussed, analysed, visualised and ranked perceived challenges and opportunities concerning academic publishing. The authors then delved into the existing literature on the subject. Following their enhanced understanding of the area, the authors reflected on the experience and learnings. Findings – Personal confidence relating to the development of a scholarly identity was found to be a critical factor in the attitude towards journal publishing. Supervisory and peer support, accessibility to journal editors, as well as opportunities to reflect on the writing, publishing and peer review processes through participatory workshops and writing groups, were deemed more effective than formal and conventional guidance schemes. Research limitations/implications – This work adds to the available literature regarding the issue of academic publishing for PhD students and early career researchers. Originality/value – The paper contributes to a deeper understanding of issues surrounding publishing apprehension, by laying out thoughts that are seldom expressed

    Production and digital image correlation analysis of titanium foams with different pore morphologies as a bone-substitute material

    Get PDF
    Ti foams are mesoporous structured materials that are characterized by their high surface area and interconnected porosity with a huge potential for biomedical applications. In this study, we investigated the production of titanium foams with different pore morphologies as a bone-substitute material via the addition of different amounts, shapes, and sizes of the space holder. Furthermore, we also carried out strain analysis using digital image correlation (DIC) in order to analyse the strain distribution across the porous samples. In addition, the nature of the relationship between the amount of the space holder added and final amount of porosity in the foams produced was also examined. The results demonstrated that the relationship between the space holder amount and porosity in the samples follows a complex one-phase exponential decay function in an increasing form. Our findings also suggest that the shape of the space holder does not play a significant role in dictating the porosity of the foams produced in the current study. However, the space holder’s shape does have a substantial role in dictating the mechanical properties of the foams produced, where Ti foams produced using a cubic or irregular space holder were found to have a lower yield stresses than those made with the spherical space holder

    The effect of density and feature size on mechanical properties of isostructural metaffic foams produced by additive manufacturing

    Get PDF
    Simple models describing the relationship between basic mechanical properties and the relative density of various types of porous metals (such as foams, sponges and lattice structures) are well established. Carefully evaluating these relationships experimentally is challenging, however, because of the stochastic structure of foams and the fact that it is difficult to systematically isolate density changes from variations in other factors, such as pore size and pore distribution. Here a new method for producing systematic sets of stochastic foams is employed based on electron beam melting (EBM) additive manufacturing (AM). To create idealised structures, structural blueprints were reverse-engineered by inverting X-ray computed tomographs of a randomly packed bed of glass beads. This three-dimensional structure was then modified by computer to create five foams of different relative density ρr, but otherwise consistent structure. Yield strength and Young’s modulus have been evaluated in compression tests and compared to existing models for foams. A power of 3 rather than a squared dependence of stiffness on relative density is found, which agrees with a recent model derived for replicated foams. A similar power of 3 relation was found for yield strength. Further analysis of the strength of nominally fully dense rods of different diameters built by EBM AM suggest that surface defects mean that the minimum size of features that can be created by EBM with similar strengths to machined samples is ∼1 mm

    Mortality from abdominal aortic aneurysm: trends in European Union 15+countries from 1990 to 2017

    Get PDF
    Background This observational study assessed trends in abdominal aortic aneurysm (AAA) death rates in European Union (EU) 15+ countries for the years 1990 to 2017. Methods Age‐standardized death rates (ASDRs) were extracted from the Global Burden of Disease Study Global Health Data Exchange. Trends were analysed using joinpoint regression analysis. Results Between 1990 and 2017, ASDRs from AAA decreased in all 19 EU15+ countries for women, and in 18 of 19 countries for men. Increasing AAA mortality was observed only for men in Greece (+5·3 per cent). The largest relative decreases in ASDR between 1990 and 2017 were observed in Australia (men –65·6 per cent, women –50·4 per cent) and Canada (men –60·8 per cent, women –48·6 per cent). Over the 28‐year interval, the smallest decreases in ASDR for women were noted in Greece (–2·3 per cent) and in Italy (–2·5 per cent). In 2017, the highest mortality rates were observed in the UK for both men and women (7·5 per 100 000 and 3·7 per 100 000 respectively). The lowest ASDR was observed in Portugal for men (2·8 per 100 000) and in Spain for women (1·0 per 100 000). ASDRs for AAA in 2017 were higher for men than women in all 19 EU15+ countries. The most recent trends demonstrated increasing AAA ASDRs in 14 of 19 countries for both sexes; the increases were relatively small compared with the improvements in the preceding years. Conclusion This observational study identified decreasing mortality from AAA across EU15+ countries since 1990. The most recent trends demonstrated relatively small increases in AAA mortality across the majority of EU15+ countries since 2012

    Feasibility of MRI based extracellular volume fraction and partition coefficient measurements in thigh muscle

    Get PDF
    OBJECTIVE: This study aimed to assess the feasibility of extracellular volume-fraction (ECV) measurement, and time to achieve contrast equilibrium (CE), in healthy muscles, and to determine whether in-flow and partial-volume errors in the femoral artery affect measurements, and if there are differences in the partition coefficient (λ) between muscles. METHODS: T1 was measured in the biceps femoris, vastus intermedius, femoral artery and aorta of 10 healthy participants. This was repeated alternately between the thigh and aorta for ≥25 min following a bolus of gadoterate meglumine. λ was calculated for each muscle/blood measurement. Time to CE was assessed semi-quantitatively. RESULTS: 8/10 participants achieved CE. Time to CE = 19±2 min (mean ± 95% confidence interval). Measured λ: biceps femoris/aorta = 0.210±0.034, vastus intermedius/aorta = 0.165±0.015, biceps femoris/femoral artery = 0.265±0.054, vastus intermedius/femoral artery = 0.211±0.026. There were significant differences in λ between the muscles when using the same vessel (p < 0.05), and between λ calculated in the same muscle when using different vessels (p < 0.05). CONCLUSION: ECV measurements in the thigh are clinically feasible. The use of the femoral artery for the blood measurement is associated with small but significant differences in λ. ECV measurements are sensitive to differences between muscles within the healthy thigh. ADVANCES IN KNOWLEDGE: This paper determines the time to contrast equilibrium in the healthy thigh and describes a method for measuring accurately ECV in skeletal muscle. This can aid in the diagnosis and understanding of inflammatory auto-immune diseases

    Trends in prevalence, mortality, and disability-adjusted life-years relating to chronic obstructive pulmonary disease in Europe: an observational study of the global burden of disease database, 2001-2019

    Get PDF
    Introduction Chronic Obstructive Pulmonary Disease (COPD) is associated with significant mortality and well-defined aetiological factors. Previous reports indicate that mortality from COPD is falling worldwide. This study aims to assess the burden of COPD using prevalence, mortality, and disability-adjusted life years (DALYs) between 2001 and 2019 in 28 European countries (the European Union and the United Kingdom). Methods We extracted COPD data from the Global Burden of Disease database based on the International Classification of Diseases versions 10 (J41, 42, 43, 44 and 47). Age-standardised prevalence rates (ASPRs), age-standardised mortality rates (ASMRs), and DALYs were analysed for European countries by sex for each year (2001–2019) and reported per 100,000 population. We used Joinpoint regression analysis to quantify changing trends in the burden of COPD. Results In 2019, the median ASPR across Europe was 3230/100,000 for males and 2202/100,000 for females. Between 2001 and 2019, the median percentage change in ASPR was − 9.7% for males and 4.3% for females. 23/28 countries demonstrated a decrease in ASPRs in males, and 11/28 demonstrated a decrease in females. The median percentage change in ASMR between 2001 and 2019 was − 27.5% for males and − 10.4% for females. 25/28 and 19/28 countries demonstrated a decrease in ASMR in males and females, respectively. Conclusion In the EU between 2001 and 2019 COPD prevalence has overall increased in females but continues to decrease in males and in some countries, female prevalence now exceeds that of males. COPD mortality in the EU has decreased overall between 2001 and 2019; however, this decrease is not universal, particularly in females, and therefore remains a substantial source of amenable mortality

    Trends of HIV-related cancer mortality between 2001 and 2018: an observational analysis

    Get PDF
    The burden of AIDS-defining cancers has remained relatively steady for the past two decades, whilst the burden of non-AIDS-defining cancer has increased. Here, we conduct a study to describe mortality trends attributed to HIV-associated cancers in 31 countries. We extracted HIV-related cancer mortality data from 2001 to 2018 from the World Health Organization Mortality Database. We computed age-standardized death rates (ASDRs) per 100,000 population using the World Standard Population. Data were visualized using Locally Weighted Scatterplot Smoothing (LOWESS). Data for females were available for 25 countries. Overall, there has been a decrease in mortality attributed to HIV-associated cancers among most of the countries. In total, 18 out of 31 countries (58.0%) and 14 out of 25 countries (56.0%) showed decreases in male and female mortality, respectively. An increasing mortality trend was observed in many developing countries, such as Malaysia and Thailand, and some developed countries, such as the United Kingdom. Malaysia had the greatest increase in male mortality (+495.0%), and Canada had the greatest decrease (-88.5%). Thailand had the greatest increase in female mortality (+540.0%), and Germany had the greatest decrease (-86.0%). At the endpoint year, South Africa had the highest ASDRs for both males (16.8/100,000) and females (19.2/100,000). The lowest was in Japan for males (0.07/100,000) and Egypt for females (0.028/100,000)

    Large-scale pathways-based association study in amyotrophic lateral sclerosis

    No full text
    Sporadic amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disease, most likely results from complex genetic and environmental interactions. Although a number of association studies have been performed in an effort to find genetic components of sporadic ALS, most of them resulted in inconsistent findings due to a small number of genes investigated in relatively small sample sizes, while the replication of results was rarely attempted. Defects in retrograde axonal transport, vesicle trafficking and xenobiotic metabolism have been implicated in neurodegeneration and motor neuron death both in human disease and animal models. To assess the role of common genetic variation in these pathways in susceptibility to sporadic ALS, we performed a pathway-based candidate gene case-control association study with replication. Furthermore, we determined reliability of whole genome amplified DNA in a large-scale association study. In the first stage of the study, 1277 putative functional and tagging SNPs in 134 genes spanning 8.7 Mb were genotyped in 822 British sporadic ALS patients and 872 controls using whole genome amplified DNA. To detect variants with modest effect size and discriminate among false positive findings 19 SNPs showing a trend of association in the initial screen were genotyped in a replication sample of 580 German sporadic ALS patients and 361 controls. We did not detect strong evidence of association with any of the genes investigated in the discovery sample (lowest uncorrected P-value 0.00037, lowest permutation corrected P-value 0.353). None of the suggestive associations was replicated in a second sample, further excluding variants with moderate effect size. We conclude that common variation in the investigated pathways is unlikely to have a major effect on susceptibility to sporadic ALS. The genotyping efficiency was only slightly decreased (∼1%) and genotyping quality was not affected using whole genome amplified DNA. It is reliable for large scale genotyping studies of diseases such as ALS, where DNA sample collections are limited because of low disease prevalence and short survival time. © 2007 The Author(s)

    Energy absorption in lattice structures in dynamics: Experiments

    Get PDF
    Lattice structures offer the potential to relatively easily engineer specific (meso-scale properties (cell level)), to produce desirable macro-scale material properties for a wide variety of engineering applications including wave filters, blast and impact protection systems, thermal insulation, structural aircraft and vehicle components, and body implants. The work presented here focuses on characterising the quasi-static and, in particular, the dynamic load-deformation behaviour of lattice samples. First, cubic, diamond and re-entrant cube lattice structures were tested under quasi-static conditions to investigate failure process and stress–strain response of such materials. Following the quasi-static tests, Hopkinson pressure bar (HPB) tests were carried out to evaluate the impact response of these materials under high deformation rates. The HPB tests show that the lattice structures are able to spread impact loading in time and to reduce the peak impact stress. A significant rate dependency of load-deformation characteristics was identified. This is believed to be the first published results of experimental load-deformation studies of additively manufactured lattice structures. The cubic and diamond lattices are, by a small margin, the most effective of those lattices investigated to achieve this
    corecore