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    An algorithmic approach for quantitative motion artefact grading in HRpQCT medical imaging

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    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

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    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

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    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 &amp;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

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    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

    Erythrocyte deformability correlates with systemic inflammation

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    Recent evidence suggests that systemic conditions, particularly those associated with inflammation, can affect erythrocyte deformability in the absence of haematological conditions. In this exploratory study, we investigated the relationship between systemic inflammatory status and erythrocyte deformability (using osmotic gradient ektacytometry) in a heterogenous study population consisting of individuals with no medical concerns, chronic conditions, and acute illness, providing a wide range of systemic inflammation severity.22 participants were included in a prospective observational study. Maximum Elongation Index (EImax) in ektacytometry served as the readout for erythrocyte deformability. Inflammatory status was assessed using C-reactive protein (CRP) and self-reported symptoms associated with inflammatory activation (Sickness Questionnaire Scores, SicknessQ).In a univariate linear regression, both CRP and SicknessQ scores significantly predicted EImax (CRP: F(1,20) = 7.751, p &lt; 0.05 (0.011), R2 = 0.279; SicknessQ: F(1,18) = 4.831, p &lt; 0.05 (0.041), R2 = 0.212). Sensitivity analyses with multivariable linear regression correcting for age showed concordant findings.Results suggest a linear relationship between erythrocyte deformability and biochemical and clinical markers of systemic inflammation. Replication of findings in a larger study, and mechanisms and clinical consequences need further in investigation

    Bank deregulation and corporate social responsibility

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    We show how external credit market development can affect corporate social responsibility. Using a sample of US public firms over the period 1991–2010, we find that bank deregulation negatively affects CSR performance. We argue that deregulation-induced banking competition enhances credit accessibility, thereby reducing firms’ incentives to pursue CSR as a means of securing stakeholder rewards. Empirical evidence shows that firms increase their use of debt financing in response to the intensified banking competition, and these firms experience a more pronounced decline in CSR performance. We alleviate the potential concern that the observed decline in CSR could be attributed to changes in bank monitoring following deregulation. Further analyses find that firms reduce CSR regardless of their material nature, suggesting that the primary driver of CSR could be the trade-off between costs and returns. Overall, our findings shed light on the strategic motives of CSR, which exhibits adaptability in response to business dynamism.</p

    Total neoadjuvant therapy in oesophageal and gastro-oesophageal junctional adenocarcinoma

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    Adenocarcinoma of the oesophagus and gastro-oesophageal junction represent a large burden of cancer death in the Western World with an increasing incidence. In the past two decades, the overall survival of patients on a potentially curative treatment pathway has more than doubled due to the addition of perioperative oncological therapies to surgery. However, patients often fail to respond to oncological treatment or struggle to complete their treatment after surgery. In this review, we discuss the current evidence for total neoadjuvant therapy and options for assessment of treatment response

    Lethal and sub-lethal responses of rocky shore gastropods to extreme temperatures

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    Intertidal communities are more frequently experiencing extreme air and sea temperatures as a result of anthropogenic climate change, with heatwaves increasing in intensity and duration. Most studies exploring the thermal tolerances of intertidal species to extreme temperatures haven't directly studied early life stages. We explored whether locally extreme tide-out temperatures were lethally impacting premature Boreal (Littorina littorea and Steromphala cineraria) and Lustanian (Phorcus lineatus and Steromphala umbilicalis) intertidal gastropod species from southwest England. Two separate experiments tested lethal and sub-lethal responses to simulated local heatwave and cold spell temperatures. Two sensitive early size classes (new recruits and year 1+ juveniles) for each species were exposed to simulated extreme and ambient tide-out temperatures in replicated boulderfield (air) and rockpool (seawater) microhabitats per experiment. Realistic experimental temperatures were determined by EnvLogger temperature data recorded locally in sun-exposed, shaded and rockpool intertidal habitats. For each nine-day experiment, specimens were exposed for six hours daily to four laboratory thermal treatments simulating both ambient conditions and extreme temperature events. These experiments were designed to test the following questions: are premature trochids and littorinids more sensitive to extreme temperatures than adults, and is there a difference in response between species of Boreal and Lusitanian origin sampled from the same geographical region? We identified that the premature intertidal trochid species may not be more thermally sensitive than adults, although premature L. littorina may have a slightly lower lethal heat limit. Survivorship in extreme heatwave air temperatures (40.0–42.9 °C) was lowest for lowshore and highest for highshore species, relating directly to species' vertical shore zonation. There were minimal to zero mortalities in all other thermal treatments. Following stress-induced inactivity in the extreme heatwave air temperature treatment, S. cineraria and P. lineatus specimens all died. In contrast, L. littorea and S. umbilicalis specimens recovered in some instances. Intensifying and more frequent aerial heatwave events occurring unseasonably are likely to cause population declines, local extinctions or subtidal retreat for premature lowshore Boreal intertidal species, influencing recruitment to adult populations, especially where rockpools are not present to provide thermal refugia. Conversely, mid-highshore Lusitanian species are likely to be more resilient to high air temperatures during low tides. Cold spell temperatures did not lethally or sub-lethally impact any juvenile gastropod species, suggesting Lusitanean species will thrive as a result of increasingly milder winters

    Scaling up noncommunicable disease care in a resource-limited context: lessons learned and implications for policy

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    BACKGROUND: Although primary care models for the care of common non-communicable diseases (NCD) have been developed in sub-Saharan Africa, few have described an integrated, decentralized approach at the community level. We report the results of a four-year, Ethiopian project to expand this model of NCD care to 15 primary hospitals and 45 health centres encompassing a wide geographical spread and serving a population of approximately 7.5 million people.METHODS: Following baseline assessment of the 60 sites, 30 master trainers were used to cascade train a total of 621 health workers in the diagnosis, management and health education of the major common NCDs identified in a scoping review (hypertension, diabetes, chronic respiratory disease and epilepsy). Pre- and post-training assessments and regular mentoring visits were carried out to assess progress and remedy supply or equipment and medicines shortages and establish reporting systems. The project was accompanied by a series of community engagement activities to raise awareness and improve health seeking behaviour.RESULTS: A total of 643,296 people were screened for hypertension and diabetes leading to a new diagnosis in 24,313 who were started on treatment. Significant numbers of new cases of respiratory disease (3,986) and epilepsy (1,925) were also started on treatment. Mortality rates were low except among patients with hypertension in the rural health centres where 311 (10.2%) died during the project. Loss to follow up (LTFU), defined as failure to attend clinic for &gt; 6 months despite reminders, was low in the hospitals but represented a significant problem in the urban and rural health centres with up to 20 to 30% of patients with hypertension or diabetes absenting from treatment by the end of the project. Estimates of the population disease burden enrolled within the project, however, were disappointing; asthma (0.49%), hypertension (1.7%), epilepsy (3.3%) and diabetes (3.4%).CONCLUSION: This project demonstrates the feasibility of scaling up integrated NCD services in a variety of locations, with fairly modest costs and a methodology that is replicable and sustainable. However, the relatively small gain in the detection and treatment of common NCDs highlights the huge challenge in making NCD services available to all.</p

    Continuum modeling of slightly wet fluidization with electrical capacitance tomograph validation

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    Gas–solid fluidized bed reactors are widely used in the power generation industry. The critical effect of the presence of liquid phase, either as a result of heat, chemical reaction or physical interaction, on the hydrodynamics of the reactor is well recognized by academic researchers and industrial operators. However, theory and simulation frameworks to predict such a condition using the continuum modeling approach are not yet available. This study first shows the significant changes in the flow pattern and distinguishable flow regimes in a slightly wet fluidized bed recorded by an advanced imaging technique. The study then describes the development and implementation of new mathematical formulations for wet particle-particle interactions in a continuum model based on the classic kinetic theory of granular flow (KTGF). Quantitative validation, carried out by comparing the predicted and measured fluidization index (FI) expressed in terms of pressure drop, has shown a good match. The prediction also demonstrates increased bubble splitting, gas channeling, slugging fluidization, and energy dissipation induced by liquid bridges developing from wet particle interactions. These characteristics are similar to those commonly observed in the fluidization of cohesive powders. This model constitutes an important step in extending the continuum theories of dry flow to wet particle-particle interactions. This will allow accurate description and simulation of the fluidized bed in its widest application including power generation systems that involve wet particle fluidizatio

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