210218 research outputs found
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Economics of geotechnical asset deterioration, maintenance and renewal
Transport and other infrastructure systems are supported by, adjacent to and retained by extensive systems of earthworks of varying (and increasing) age, and of variable quality of original construction. These earthworks are subject to natural deterioration, which can be accelerated and complicated by the effects of climate change. The ACHILLES research program is providing improved understanding of earthworks behavior, performance and deterioration, and is developing methods and tools to provide decision support for the construction, maintenance and renewal of earthworks, with particular emphasis on the management of existing, deteriorating assets. Conventional cost-benefit analysis methods, of the type used for new infrastructure projects, do not directly provide the decision support needed for the maintenance and renewal of existing earthworks assets, and an alternative approach is proposed and demonstrated. The handling of the uncertainty associated with earthworks behavior, deterioration rates and times to failure is also considered, as is the extension of the single-asset approach to the management of multiple earthworks assets
An algorithmic approach for quantitative motion artefact grading in HRpQCT medical imaging
High Resolution Peripheral Quantitative Computed Tomography (HRpQCT) is a modern form of medical imaging that is used to extract detailed internal texture and structure information from non-invasive scans. This greater resolution means HRpQCT images are more vulnerable to motion artefact than other existing bone imaging methods. Current practice is for scan images to be manually reviewed and graded on a one to five scale for movement artefact, where analysis of scans with the most severe grades of movement artefact may not be possible. Various approaches to automatically detecting motion artefact in HRpQCT images have been described, but these typically rely on classifying scans based on the qualitative manual gradings instead of determining the amount of artefact. This paper describes research into quantitatively calculating the degree of motion affecting an HRpQCT. This is approached by analysing the jumps and shifts present in the raw projection data produced by the HRpQCT instrument scanner, rather than using the reconstructed cross-sectional images. The motivation and methods of this approach are described, and results are provided, along with comparisons to existing work.</p
Employment conditions and mental health of overseas female migrant domestic workers in Hong Kong: a parallel mediation analysis
Background: female migrant domestic workers (MDW), approximately 8.5 million globally, often live in their employer’s home under vulnerable conditions. In Hong Kong, MDWs currently comprise 5% of the population. This study was conducted to assess the association between employment conditions and mental health, and the mediating roles stress and job satisfaction have, among female MDWs in Hong Kong.Methods: participants completed an online cross-sectional survey. A total of 1,965 survey were collected between August 2020 and August 2021. Questions in the survey were related to MDWs background information, employment conditions, stress, job satisfaction, and two mental health outcomes: anxiety and depression. An employment conditions score was created to assess the cumulative effect poor employment conditions had on mental health. A multicategorical parallel mediation analysis was used to assess the direct effect employment conditions have on mental health and the indirect effects through stress and job satisfaction.Results: overall, 17.7% of MDWs were reported to be suffering from anxiety and 30.8% from depression. An increase in poor employment conditions was statistically associated with an increase in both outcomes, while stress levels and job satisfaction mediated this association.Conclusions: the findings call for increased scrutiny of employment conditions and mental well-being of MDWs
Nonlinear electromagnetic vibration energy harvester comprising dual helical-plane springs and multiple Halbach arrays for low-frequency and small-amplitude vibrations
Electromagnetic vibration energy harvesters are widely investigated for self-powered wireless sensors and nonlinearity has been introduced for low-frequency and broadband vibration energy harvesting. But how to realize the nonlinearity with small amplitudes, high reliability and few complexities is still a challenge in real-world applications. In this paper, a novel electromagnetic vibration energy harvester comprising dual helical-plane springs and multiple Halbach arrays is proposed. The structural characteristics are analyzed, which indicate that the helical-plane springs can have nonlinear stiffness under small-amplitude vibrations and multiple Halbach arrays can greatly enhance the magnetic field. Then a magnet-electro-mechanical model is built by combining mechanical dynamics &electrodynamics, which is numerically solved by using the Runge-Kutta algorithm. Finally, the feasibility of the nonlinear electromagnetic vibration energy harvester is validated both numerically and experimentally. The results show that it has a nonlinear stiffness, a resonance bandwidth of 3 Hz and a peak power of 14 mW when the excitation amplitude is only 0.5g. In particular, the resonance frequency range depends on the excitation amplitude. Furthermore, the prototype of a self-powered wireless temperature sensor is constructed and testified. The results of this study indicate that the proposed structure can be utilized and extended to build compact, reliable and nonlinear electromagnetic vibration energy harvesters for low-frequency, small-amplitude and broadband vibrations in real-world applications
Sarcopenia definitions and their association with fracture risk in older Swedish women
The purpose of this study was to investigate the prevalence of three sarcopenia definitions and their associations with fracture risk in older Swedish women when adjusted for fracture risk assessment (FRAX)-based risk factors; 2,883 women with a mean age of 77.8 years were included. Sarcopenia was defined based on the Sarcopenia Definitions and Outcomes Consortium (SDOC; low handgrip strength [kg] and gait speed (m/s)), revised European Working Group on Sarcopenia in Older People (EWGSOP2; low appendicular lean mass index, appendicular lean mass [ALM]/height; kg/m2], and hand grip strength [kg]), and Asian Working Group for Sarcopenia (AWGS; low ALM (kg), and hand grip strength [kg]) definitions. Femoral neck T-score was obtained from dual-energy X-ray absorptiometry. All fractures, confirmed by X-ray or medical record review, were subsequently categorized as major osteoporotic fractures (MOFs) and hip fractures. Deaths were verified through regional registers. The total follow-up time was 6.4 ± 1.3 (mean ± SD) yr. Cox regression (hazard ratios [HR] and 95% CIs) analyses were performed with adjustment for age, FRAX variables, and femoral neck T-score. Sarcopenia prevalence was 4.5% (n = 129) according to SDOC, 12.5% (n = 360) for EWGSOP2, and 10.3% (n = 296) defined by AWGS. Individuals with sarcopenia defined by SDOC had a higher mortality risk than individuals without sarcopenia (HR: 3.41; 95% CI: 2.51, 4.62) after adjusting for age and FRAX variables. Sarcopenia according to EWGSOP2 and AWGS was not associated with an increased fracture risk after adjusting for age and FRAX variables. Individuals with sarcopenia defined by SDOC had a higher risk for any fractures (HR: 1.48; 95% CI: 1.10, 1.99) and MOF (HR: 1.42; 95% CI: 1.03, 1.98) compared with individuals without sarcopenia after adjusting for clinical risk factors used in FRAX. In conclusion, sarcopenia defined by SDOC, incorporating muscle function/strength, was the only sarcopenia definition associated with fracture risk in older women.</p
Causes and solutions to workplace psychological ill-health for nurses, midwives and paramedics: the Care Under Pressure 2 realist review
Background: Nurses, midwives and paramedics are the largest collective group of clinical staff in the National Health Service and have some of the highest prevalence of psychological ill-health. Existing literature tends to be profession-specific and focused on individual interventions that place responsibility for good psychological health with nurses, midwives and paramedics themselves. Aim: To improve understanding of how, why and in what contexts nurses, midwives and paramedics experience work-related psychological ill-health; and determine which high-quality interventions can be implemented to minimise psychological ill-health in these professions. Methods: Realist synthesis methodology consistent with realist and meta-narrative evidence syntheses: evolving standards' reporting guidelines. Data sources: First round database searching in Medical Literature Analysis and Retrieval System Online Database ALL (via Ovid), cumulative index to nursing and allied health literature database (via EBSCO) and health management information consortium database (via Ovid), was undertaken between February and March 2021, followed by supplementary searching strategies (e.g. hand searching, expert solicitation of key papers). Reverse chronology screening was applied, aimed at retaining 30 relevant papers in each profession. Round two database searches (December 2021) targeted COVID-19-specific literature and literature reviews. No date limits were applied. Results: We built on seven key reports and included 75 papers in the first round (26 nursing, 26 midwifery, 23 paramedic) plus 44 expert solicitation papers, 29 literature reviews and 49 COVID-19 focused articles in the second round. Through the realist synthesis we surfaced 14 key tensions in the literature and identified five key findings, supported by 26 context mechanism and outcome configurations. The key findings identified the following: (1) interventions are fragmented, individual-focused and insufficiently recognise cumulative chronic stressors; (2) it is difficult to promote staff psychological wellness where there is a blame culture; (3) the needs of the system often override staff well-being at work ('serve and sacrifice'); (4) there are unintended personal costs of upholding and implementing values at work; and (5) it is challenging to design, identify and implement interventions to work optimally for diverse staff groups with diverse and interacting stressors. Conclusions: Our realist synthesis strongly suggests the need to improve the systemic working conditions and the working lives of nurses, midwives and paramedics to improve their psychological well-being. Individual, one-off psychological interventions are unlikely to succeed alone. Psychological ill-health is highly prevalent in these staff groups (and can be chronic and cumulative as well as acute) and should be anticipated and prepared for, indeed normalised and expected. Healthcare organisations need to (1) rebalance the working environment to enable healthcare professionals to recover and thrive; (2) invest in multi-level system approaches to promote staff psychological well-being; and use an organisational diagnostic framework, such as the NHS England and NHS Improvement Health and Wellbeing framework, to self-assess and implement a systems approach to staff well-being. Future work: Future research should implement, refine and evaluate systemic interventional strategies. Interventions and evaluations should be co-designed with front-line staff and staff experts by experience, and tailored where possible to local, organisational and workforce needs. Limitations: The literature was not equivalent in size and quality across the three professions and we did not carry out citation searches using hand searching and stakeholder/expert suggestions to augment our sample. Study registration: This study is registered as PROSPERO CRD42020172420. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020172420. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme (NIHR award ref: NIHR129528) and is published in full in Health and Social Care Delivery Research; Vol. 12, No. 9. See the NIHR Funding and Awards website for further award information.</p
Tackling inequalities in preconception health and care: barriers, facilitators and recommendations for action from the 2023 UK Preconception EMCR Network conference
Reducing inequalities in preconception health and care is critical to improving the health and life chances of current and future generations. A hybrid workshop was held at the 2023 UK Preconception Early and Mid-Career Researchers (EMCR) Network conference to co-develop recommendations on ways to address inequalities in preconception health and care. The workshop engaged multi-disciplinary professionals across diverse career stages and people with lived experience (total n=69). Interactive discussions explored barriers to achieving optimal preconception health, driving influences of inequalities, and recommendations. The Socio-Ecological Model framed the identified themes, with recommendations structured at interpersonal (e.g. community engagement), institutional (e.g. integration of preconception care within existing services) and environmental/societal levels (e.g. education in schools). The co-developed recommendations provide a framework for addressing inequalities in preconception health, emphasising the importance of a whole-systems approach. Further research and evidence-based interventions are now needed to advance the advocacy and implementation of our recommendations
Unlocking the potential of research-informed practice: insights into benefits, challenges, and significance among teachers in Catalonia, Poland, and England
This survey-based study delves into the intricate interplay of research utilisation in the pedagogical approaches of a sample of 534 teachers across Catalonia (Spain), Poland, and England. Applying Baudrillard's Theory of Consumption lenses, we present novel insights into the multifaceted aspects of research use, including its benefits, costs, and significance within the teaching profession. Our findings underscore the interdependencies among the perceived benefits, costs, and significance of research utilisation, bolstered by factor analysis. Specifically, our results indicate that teachers regard research as a means to enhance their understanding of educational theories, providing valuable insights to inform their teaching practices. Moreover, research empowers teachers to challenge entrenched conceptions and adopt innovative pedagogical strategies. In addition, the significance of research use is associated with its alignment with school priorities and integration into the decision-making processes. Furthermore, teachers identified various obstacles to research use, including issues of research literacy, support mechanisms, and the accessibility of research resources. The study sheds additional insight into the dynamics of research utilisation among teachers operating within diverse national contexts. It underscores the intricate relationships between individual and organisational factors that shape and influence teaching practices.</p
Testing and numerical modelling of circular stainless steel reinforced concrete columns
Chloride-induced corrosion of carbon steel reinforcing bars is considered the primary cause of deterioration of reinforced concrete (RC) structures. Stainless steel rebars have gained increasing attention in recent years as a promising alternative to the traditional carbon steel rebars to overcome the problem of chloride-induced reinforcement corrosion in RC structures. This paper presents the results of a new experimental testing program on two circular RC columns, subjected to lateral cyclic loading, reinforced with two different stainless steel reinforcing bar grades: austenitic EN 1.4301 and duplex EN 1.4362. A third RC column reinforced with carbon steel reinforcing bar was tested as a control specimen. The resultant force-displacement relationships, damage, energy dissipation, secant stiffness, and moment-curvature relationships from digital image correlation (DIC) are presented and discussed. Finally, an advanced OpenSees finite element model, validated against the conducted tests, for simulating the cyclic response of RC columns is presented
Ligon's Hands; or, querying Frank's Sublime
Jason Frank’s The Democratic Sublime (2021) is a fascinating and compelling account of the aesthetic-political stakes of popular sovereignty and manifestation as it emerges in the age of democratic revolutions. Frank shows us how, in the age of democratic revolutions, the staging of the People was equally – indeed, more fundamentally – an aesthetic problem. It is a question always of appearance, manifestation and demonstration. The Sublime is central to Frank’s argument for precisely this reason. It becomes the aesthetic category par excellence to mark the experience of that which is excessive to all sensuous apprehension but is nonetheless rendered sensually. The democratic sublime, more directly, marks the aporetic moment constitutive of popular manifestation. Yet, as much as these Sublime aporias are developed in the direction of a productive tension in Frank’s account, they also mark a process or operation that – as decolonial critiques have shown – grounds a whole orchestration of bodies. The sublime is that category by which and in which such an elemental differentiation is at work. Sublime experience is that operation in which the boundaries of subject and object, body and flesh, sense and sentience – in a word a boundary of the proper – are first instituted. The very aporias in which Frank wants to locate the appearance of a radical excess, of the part of no part, are those in which that supplement is tamed and brought to its knees, dominated and captured. And it isn’t clear how far a democratic augment to the Sublime can move us away from this colonial-anthropologising operation. Which is to say, holding open that aporetic terrain between representation and impossibility, resisting identification, subjectivation and recognition appears to be already and constitutively a differentiation of the proper subject and its others.<br/