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CALPHAD aided design of a crack-free Al-Mg-Si-Ti alloy with high strength: heterogeneous nucleation and eutectic filling during additive manufacturing
Get PDFData availability statement: Data will be made available on request.Supplemental material is available online at: https://www.tandfonline.com/doi/full/10.1080/17452759.2024.2378930# .The CALPHAD (calculation of phase diagrams) method was applied to facilitate the design of a crack-free Al-Mg-Si-Ti alloy fabricated by laser-powder bed fusion (L-PBF). Calculation and alloy characterisation show that Ti addition at 0.77 wt.% can offer a synergic effect of increasing the heterogeneous nucleation rate and the growth restriction factor (Q) in the initial solidification stage. Meanwhile, the increase of Mg/Si ratio can promote the formation of Al/Mg2Si eutectics to provide excellent backfilling ability in the final solidification stage. As a result, the experimental Al-Mg-Si-Ti alloy significantly improve the crack susceptibility. Also, the Al-Mg-Si-Ti alloy with dislocation interaction of Al/Mg2Si eutectics and Al3Ti particles show an excellent ultimate tensile strength of 447.8 MPa and elongation of 9.1% under as-LPBFed condition.National Natural Science Foundation of China (grant number 52071343); Leading Innovation and Entrepreneurship Team of Zhejiang Province – Automotive Light Alloy Innovation Team (2022R01018)
Longitudinal change in ultrasound-derived rectus femoris cross-sectional area in COPD
Get PDFBackground:
Skeletal muscle dysfunction is common in chronic obstructive pulmonary disease (COPD). Ultrasound-derived rectus femoris cross-sectional area (RFCSA) is a radiation free, non-invasive measure of muscle bulk that relates to quadriceps strength in people with COPD. However, there are limited longitudinal data for RFCSA, and it is not known whether longitudinal change in RFCSA reflects change in quadricep strength, exercise capacity, lower limb function or muscle mass. We aimed to quantify longitudinal change in ultrasound-derived RFCSA and assess its relationship with change in quadriceps maximal voluntary contraction (QMVC), incremental shuttle walk test (ISWT), five repetition sit-to-stand (5STS) and fat free mass (FFM) over 12 months in people with COPD.
Methods:
We measured ultrasound-derived RFCSA, QMVC, ISWT, 5STS and FFM (measured by bioelectric impedance analysis) at baseline and 12 months in 169 people with stable COPD. Change was correlated using Pearsons or Spearman's coefficients.
Results:
Baseline characteristics: Mean (sd) age 70 (9.4) years; FEV1 52.6 (18.8)% predicted. Over the course of 12 months mean (99% confidence interval) RFCSA change was −33.7mm2 (−62.6 to −4.9, p=0.003) representing a mean (sd) percentage change of −1.8% (33.5). There was a weak correlation between change in RFCSA and FFM (r=0.205 p=0.009), but not with change in QMVC, ISWT or 5STS.
Conclusion:
There is a statistically significant decrease in ultrasound-derived RFCSA over 12 months in people with stable COPD, but this decrease does not correlate with change in quadriceps strength, exercise capacity, fat free mass nor lower limb function.This cohort study was funded by a Medical Research Council (UK) New Investigator Research Grant (G1002113) awarded to WM. MM is part funded by the National Institute for Health and Care Research (NIHR) Applied Research Collaboration South London. TOJ is funded by a Health Education England and National Institute for Health Research (NIHR) ICA Predoctoral Clinical and Practitioner Academic Fellowship
Single-Phase Pressure Drop and Heat Transfer in Micro-Pin Fin Heat Exchangers
Get PDFAbstract number 6 (https://more.bham.ac.uk/ukhtc-2024/programme/).Single-phase flow of HFE-7100 in a micro-pin fin heat sink was investigated and the results described in this paper. Both adiabatic and diabatic experiments were carried out at a system pressure of 1 bar, inlet fluid temperature of 19 ⁰C and Reynolds number ranging from 86 to 850. Different existing correlations of friction factor and Nusselt number were evaluated and assessed. A good agreement between the present results and some correlations was found.EPSRC grant EP/S019502/1
From riverbank to the sea: An initial assessment of plastic pollution along the Ciliwung River, Indonesia
Get PDFData availability: Data will be made available on request.Supplementary data are available online at: https://www.sciencedirect.com/science/article/pii/S0025326X24006398?via%3Dihub#s0090 .This study presents the first comprehensive analysis of anthropogenic debris on the riverbanks of the Ciliwung River, covering upstream to downstream areas. The mean of debris found in each measurement was 32.79 ± 15.38 items/m2 with a weight of 106.00 ± 50.23 g/m2. Plastic debris accounted for over 50 % of all litter items identified and represents 55 % by weight, signifying a significantly high prevalence compared to global studies examining litter along riverbanks. The majority of the plastics found originated from Single-use applications and were predominantly made from Styrofoam. This investigation demonstrated the importance of actions to reduce single use applications and to improve waste management strategies. This can be achieved through proactive initiatives coupled with adaptable approaches, such as implementing effective urban planning and enhancing waste collection capacity.The research was made possible through the support of “A Systems Analysis Approach to Reduce Plastic Waste in Indonesian Societies (PISCES)”, funded by UK Research and Innovation (UKRI) and UK Global Challenges Research Fund (GCRF) (Grant Ref: NE/V006428/1). PISCES aims to inform, complement, and catalyze national and global action programs to solve the plastic challenge (https://www.piscespartnership.org/)
Professor David Denver
Get PDFProfessor David Denver, who died in August 2024, made an outstanding contribution to the study of elections, public opinion and parties.
The legacy of his scholarly work is considerable, most obviously in his pioneering work on election campaigning. Experiments are now de rigueur in the discipline, but in 1970, Denver (along with John Bochel) conducted the first field experiment in British political science, demonstrating the electoral impact of campaigns on the ground. Published in the British Journal of Political Science in 1971, this work was the first in a long line of analysis which turned on its head what was at that point the conventional approach to the analysis of British elections. Rather than being an ineffective relic, Denver showed that local campaigning had the potential to alter the outcome
Acceptability of a remotely delivered sedentary behaviour intervention to improve sarcopenia and maintain independent living in older adults with frailty: a mixed-methods study
Get PDFAvailability of data and materials: The datasets supporting the conclusions of this article are available in Figshare, https://doi.org/10.17633/rd.brunel.26028892.v1. The raw qualitative data (transcripts) are not publicly available due to privacy restrictions. Further detail on the qualitative data and analysis that supports the findings of this study are available upon request to the corresponding author.Supplementary Information is available online at: https://bmcgeriatr.biomedcentral.com/articles/10.1186/s12877-024-05385-4#Sec222 .Background:
Sarcopenia is a leading cause of functional decline, loss of independence, premature mortality, and frailty in older adults. Reducing and breaking up sedentary behaviour is associated with positive sarcopenia and frailty outcomes. This study aimed to explore the acceptability, engagement and experiences of a remotely delivered sedentary behaviour intervention to improve sarcopenia and independent living in older adults with frailty.
Methods:
This was a mixed-methods study. In-depth qualitative semi-structed interviews were conducted with a subset (N = 15) of participants with frailty (aged 74 ± 6 years) who had participated in the Frail-LESS (LEss Sitting and Sarcopenia in Frail older adults) intervention aimed at reducing sedentary behaviour. The interviews explored acceptability of the intervention overall and its individual components (a psychoeducation workbook, wrist-worn activity tracker, health coaching, online peer support and tailored feedback on sitting, standing and stepping). Process evaluation questionnaires with closed and scaled questions explored intervention engagement, fidelity and experiences.
Results:
Overall acceptability of the intervention was good with most participants perceiving the intervention to have supported them in reducing and/or breaking up their sedentary behaviour. The wrist-worn activity tracker and health coaching appeared to be the most acceptable and useful components, with high levels of engagement. There was attendance at 104 of 150 health coaching sessions offered and 92% of participants reported using the wrist-worn activity tracker. There was a mixed response regarding acceptability of, and engagement with, the psychoeducation workbook, tailored feedback, and online peer support.
Conclusions:
The Frail-LESS intervention had good levels of acceptability and engagement for some components. The findings of the study can inform modifications to the intervention to optimise acceptability and engagement in a future definitive randomised controlled trial.Abbeyfield Research Foundatio
On the refined boundary condition at the edge of a thin elastic strip supported by a Winkler-type foundation under antiplane shear deformation
No full textData availability:
No data was used for the research described in the article.The derivation of the boundary conditions is the most challenging part of the asymptotic techniques underlying low-dimensional models for thin elastic structures. At the moment, these techniques do not take into consideration the effect of the environment, e.g., a Winkler foundation, when tackling boundary conditions, and have to be amended. In this paper as an example we consider an antiplane problem for a thin elastic strip contacting with a relatively compliant Winkler foundation. Refined boundary conditions at an edge loaded by prescribed stresses are established using a properly adjusted Saint-Venant’s principle. They appear to be useful for advanced structure modelling including analysis of the static equilibrium under self-equilibrated loading.LP, JK and WM are thankful to the H2020-MSCA-RISE project ‘EffectFact’ ID: 101008140 and their secondment industrial hosts (ROEZ, Slovakia and CAEmate, Italy) for the hospitality. LP was supported by the Engineering and Physical Sciences Research Council, UK [EP/Y021983/1]. WM also acknowledges partial support from the project within the Innovate Ukraine competition, funded by UK International Development and hosted by British Embassy Kyiv
Reducing embodied carbon emissions of buildings – a key consideration to meet the net zero target
Get PDFData availability: Data will be made available on request.The prevalence of modern techniques and industrialized materials has resulted in environmental contamination. Therefore, prioritizing the use of sustainable materials with minimal CO2 emissions should be the fundamental principle guiding future developments in construction projects. Rammed earth construction, a traditional method in Latin America, is valued for its sustainable, environmentally friendly properties. The research examines integrating Building Information Modeling (BIM) and Life Cycle Assessment (LCA) in Colombia, a region with limited exploration of BIM-LCA interoperability on earth-based materials. This study applies LCA (Cradle-to-Gate) to assess material use, and transportation, aiming to reduce construction carbon emissions. This study compares the traditional and Sustainable building environmental impacts through the BIM (using Autodesk Revit) and carbon footpring. Findings show that BIM-based models with traditional materials have significantly higher carbon footprints (171.93 kg CO2 eq per square meter) than sustainable models (62.25 kg CO2 eq per square meter). This research highlights the importance of low carbon materials for the carbon reduction to meet net zero target in construction industry
Advanced predictive modeling of shear strength in stainless-steel column web panels using explainable AI insights
Get PDFData availability:
Data will be made available on request.This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.In steel moment-resisting frames, energy dissipation occurs through yielding at the beam ends. Furthermore, the column panel zone can be designed to contribute to this energy dissipation process. The European standard (EN 1993–1–4) for stainless-steel is developed based on carbon steel procedures, without taking into account stainless steel's unique strain hardening and mechanical properties. This discrepancy may result in inaccuracies in predicting panel zone behavior. However, with the recent advancements in stainless steel, it is timely to reassess these limitations. The present research investigates the behavior of stainless-steel column web panels through an explainable artifactual intelligence methodology. This approach combines twelve widely recognized machine learning algorithms with the SHAP algorithm for enhanced explainability and transparency. In addition, a user-friendly graphical user interface has been developed to simplify engineering design. The Extra Trees Regression algorithm demonstrated the highest predictive performance, achieving R² = 0.987, mean absolute error (MAE) = 3.575 kN, and root mean square error (RMSE) = 6.464 kN for the entire dataset. The SHAP analysis revealed that bolt diameter and the column second moment of inertia are the most critical input features affecting shear strength. This approach effectively captures the nonlinear characteristics of shear behavior in stainless-steel column web panels and offers clear insights into the contribution of different factors. The developed method not only improves predictive accuracy but also promotes transparency, making it a practical tool for engineers in structural component design
Statin-treated RBC dynamics in a microfluidic porous-like network
Get PDFData availability:
Data will be made available on request.The impact of therapeutic interventions on red blood cell (RBC) deformability and microscale transport is investigated, using statins as an exemplar. Human RBCs were treated in vitro with two commonly prescribed statins, atorvastatin and rosuvastatin, at clinically relevant concentrations. Changes in RBC deformability were quantified using a microfluidic-based ektacytometer and expressed in terms of the elongation index. Dilute suspensions of the statin-treated RBCs were then perfused through a microfluidic pillar array, at a constant flow rate and negligible inertia, and imaged. Particle Tracking Velocimetry (PTV) was applied to track RBCs, identify preferential paths and estimate their velocities, whereas image processing was used to estimate cell dynamics, perfusion metrics and distributions. The findings were compared against those of healthy, untreated cells. Statins enhanced RBC deformability in agreement with literature. The extent of enhancement was found to be statin-dependent. The softer statin-treated cells were found to flow in straight, less tortuous paths, spend more time inside the pillar array and exhibit lower velocities compared to healthy RBCs, attributed to their enhanced deformation and longer shape recovery time upon impact with the array posts. The in vitro microfluidic approach demonstrated here may serve as a monitoring tool to personalise and maximise the outcome of a therapeutic treatment.EPSRC DTP programme (EP/R513143/1); Future Blood Testing Network+ (EP/W000652/1)
Data sources:
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