4,874 research outputs found

    Introduction and evaluation of peer assisted learning in first-year undergraduate bioscience.

    Get PDF
    Bioscience undergraduates, enrolled on a first-year microbiology module, participated in the introduction of peer-assisted learning (PAL) into the curriculum. The class of 122 students was divided into groups of six to ten, with one volunteer from each group assuming the role of group leader (peer tutor). Group leaders attended a compulsory training session at which they were guided through the tutorial they would lead with their peer group. The primary aim of PAL was to raise students’ self-confidence in their problem-solving and numerical skills. Students were provided with the opportunity to practise problem-solving questions from past examination papers and to discuss with their peers their answers and any difficulties they encountered, particularly with regard to any mathematics involved. Students’ perceptions of their PAL experience, their group leader’s contribution and the training provided for group leaders were evaluated using a questionnaire. The latter revealed that bioscience undergraduates found PAL a highly valuable learning experience. In particular, they found the less formal, comfortable and relaxed atmosphere of the PAL session provided them with greater freedom to ask questions and exerted less pressure on them to answer questions correctly than a more formal staff-led session, as well as assisting them to understand the topics covered

    Assessing enterprise resource planning systems success: An empirical study

    Get PDF
    Enterprise Resource Planning (ERP) systems continue to represent one of the largest IT investments in organization and increasingly becoming one of the prerequisites for doing business in many industries. Many companies worldwide have adopted ERP systems for variety of reasons, including cost reduction, integration of business processes and faster information transactions. ERP Implementation and critical success factors have been extensively researched but few studies have investigated the success of the system. This study develops a model based on the information system\u27s research to identify success measures

    Cold, anisotropically-interacting van der Waals molecule: TiHe

    Full text link
    We have used laser ablation and helium buffer-gas cooling to produce the titanium-helium van der Waals molecule at cryogenic temperatures. The molecules were detected through laser-induced fluorescence spectroscopy. Ground-state Ti-He binding energies were determined for the ground and first rotationally excited states from studying equilibrium thermodynamic properties, and found to agree well with theoretical calculations based on newly calculated ab initio Ti-He interaction potentials, opening up novel possibilities for studying the formation, dynamics, and non-universal chemistry of van der Waals clusters at low temperatures

    Validation of a physically-based solid oxide fuel cell anode model combining 3D tomography and impedance spectroscopy

    Get PDF
    This study presents a physically-based model for the simulation of impedance spectra in solid oxide fuel cell (SOFC) composite anodes. The model takes into account the charge transport and the charge-transfer reaction at the three-phase boundary distributed along the anode thickness, as well as the phenomena at the electrode/electrolyte interface and the multicomponent gas diffusion in the test rig. The model is calibrated with experimental impedance spectra of cermet anodes made of nickel and scandia-stabilized zirconia and satisfactorily validated in electrodes with different microstructural properties, quantified through focused ion beam SEM tomography. Besides providing the material-specific kinetic parameters of the electrochemical hydrogen oxidation, this study shows that the correlation between electrode microstructure and electrochemical performance can be successfully addressed by combining physically-based modelling, impedance spectroscopy and 3D tomography. This approach overcomes the limits of phenomenological equivalent circuits and is suitable for the interpretation of experimental data and for the optimisation of the electrode microstructure

    New method for the deposition of nickel oxide in porous scaffolds for electrodes in solid oxide fuel cells and electrolyzers

    Get PDF
    A simple chemical bath deposition is used to coat a complex porous ceramic scaffold with a conformal nickel layer. The resulting composite is used as a Solid Oxide Fuel Cell electrode and its electrochemical response is measured in humidified hydrogen. X-Ray tomography is used to determine microstructural parameters of the uncoated and Ni-coated porous structure, among other, the surface area to total volume, the radial pore size and size of the necks between pores

    The impact of the menopause transition on the health and wellbeing of women living with HIV: A narrative review

    Get PDF
    Improvements in survival due to advances in antiretroviral therapy (ART) have led to a shift in the age distribution of those receiving HIV care, with increasing numbers of women living with HIV (WLHIV) reaching menopausal age. We present a narrative literature review of 26 studies exploring the menopause transition in WLHIV, focusing on: (1) natural history (2) symptomatology and management, and (3) immunologic and virologic effects. Data are conflicting on the association between HIV and earlier age at menopause, and the role of HIV-specific factors such as HIV viral load and CD4 count. There are some data to suggest that WLHIV experience more vasomotor and psychological symptoms during the menopause than HIV-negative women, and that uptake of hormone replacement therapy by WLHIV is comparatively low. There is no evidence that menopause affects either CD4 count or response to ART, although there may be increased immune activation in older WLHIV. We conclude that menopause in WLHIV is a neglected area of study. Specific information gaps include qualitative studies on experiences of reproductive ageing; data on the impact of the menopause on women’s quality of life and ability to adhere to health-sustaining behaviors; as well as studies investigating the safety and efficacy of pharmacological and psychosocial interventions. There is likely to be a burden of unmet health need among this growing population, and better data are required to inform optimal provision of care, supporting WLHIV to maintain their health and wellbeing into their post-reproductive years

    HIV and trans and non-binary people in the UK

    Get PDF
    Trans and non-binary people are key populations whose HIV prevention and treatment needs have been neglected. A 2013 meta-analysis of data from 39 studies conducted in 15 countries, reported a global HIV prevalence among trans women of nearly 20%, with trans women estimated to be 49 times more likely than other adults to be living with HIV. Moreover, mortality from HIV/AIDS among trans women in a large cohort study was just over 30 times that of age-matched population controls

    Operando visualisation and multi-scale tomography studies of dendrite formation and dissolution in zinc batteries

    Get PDF
    Alternative battery technologies are required to meet growing energy demands and address the limitations of present technologies. As such, it is necessary to look beyond lithium-ion batteries. Zinc batteries enable high power density while being sourced from ubiquitous and cost-effective materials. This paper presents, for the first time known to the authors, multi-length scale tomography studies of failure mechanisms in zinc batteries with and without commercial microporous separators. In both cases, dendrites were grown, dissolved, and regrown, critically resulting in different morphology of dendritic layer formed on both the electrode and the separator. The growth of dendrites and their volume-specific areas were quantified using tomography and radiography data in unprecedented resolution. High-resolution ex situ analysis was employed to characterize single dendrites and dendritic deposits inside the separator. The findings provide unique insights into mechanisms of metal-battery failure effected by growing dendrites

    Evaluation of the accuracy of serum MMP-9 as a test for colorectal cancer in a primary care population

    Get PDF
    Background Bowel cancer is common and is a major cause of death. Meta-analysis of randomised controlled trials estimates that screening for colorectal cancer using faecal occult blood (FOB) test reduces mortality from colorectal cancer by 16%. However, FOB testing has a low positive predictive value, with associated unnecessary cost, risk and anxiety from subsequent investigation, and is unacceptable to a proportion of the target population. Increased levels of an enzyme called matrix metalloproteinase 9 (MMP-9) have been found to be associated with colorectal cancer, and this can be measured from a blood sample. Serum MMP-9 is potentially an accurate, low risk and cost-effective population screening tool. This study aims to evaluate the accuracy of serum MMP-9 as a test for colorectal cancer in a primary care population. Methods/Design People aged 50 to 69 years, who registered in participating general practices in the West Midlands Region, will be asked to complete a questionnaire that asks about symptoms. Respondents who describe any colorectal symptoms (except only abdominal bloating and/or anal symptoms) and are prepared to provide a blood sample for MMP9 estimation and undergo a colonoscopy (current gold standard investigation) will be recruited at GP based clinics by a research nurse. Those unfit for colonoscopy will be excluded. Colonoscopies will be undertaken in dedicated research clinics. The accuracy of MMP-9 will be assessed by comparing the MMP-9 level with the colonoscopy findings, and the combination of factors (e.g. symptoms and MMP-9 level) that best predict a diagnosis of malignancy (invasive disease or polyps) will be determined. Discussion Colorectal cancer is a major cause of morbidity and mortality. Most colorectal cancers arise from adenomas and there is a period for early detection by screening, but available tests have risks, are unacceptable to many, have high false positive rates or are expensive. This study will establish the potential of serum MMP-9 as a screening test for colorectal cancer. If it is confirmed as accurate and acceptable, this serum marker has the potential to assist with reducing the morbidity and mortality from colorectal cancer
    • …
    corecore