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Modelling heat transfer of timber sections subjected to non-standard fire action
No full textUsing timber as a structural material in buildings is promising in reducing the carbon footprint of construction, although fire safety has been a long-standing challenge prohibiting its wider use. The current design practice usually complies with Eurocode 5, but it is largely prescribed only for standard fire scenario. While investigating the fire behavior in real compartments containing timber members, the fire action imposed on the surface of timber members can be hardly represented by the standard fire curve. Therefore, modelling the heat transfer of timber sections in these real fire scenarios requires adequate numerical models. In this paper, the heat transfer model equipped with temperature-variant thermal properties of timber as well as a heat generation model addressing timber combustion effect, has been developed and implemented in the open-source simulation platform OpenSees for fire. Advancing from the existing heat transfer models, the present model has been validated against test results of timber sections subjected to the prescribed non-standard fire actions supported by the e-controlled radiant panel system. The modelling results have shown good performance in predicting the temperature evolution at various depths of the timber sections subjected to non-standard heating conditions
The newfound relationship between extrachromosomal DNAs and excised signal circles
No full textElevated levels of extrachromosomal DNAs (ecDNAs) are associated with poor prognoses of many cancer types. These large circular DNAs typically harbour oncogenes and regulatory elements which, together with high levels of ecDNA transcription, confer a growth advantage to cancer cells. Replication of ecDNAs, followed by their unequal distribution at mitosis, further promotes rapid cancer evolution. In contrast to ecDNAs, the role of circular DNA by-products from V(D)J recombination in cancer development has largely been overlooked. Developing lymphocytes generate millions of excised signal circles (ESCs) each day through gene rearrangement at the immunoglobulin and T-cell receptor loci. Despite their similar size to ecDNAs, ESCs were long assumed to be inert and lost during cell division. However, it is now known that ESCs potently trigger genome instability when complexed with recombinase proteins. Not only this, but new data show that just like ecDNAs, ESCs replicate and persist, with high levels strongly correlating with poor prognosis of B-cell precursor acute lymphoblastic leukaemia (BCP-ALL). Despite these striking similarities, the properties of ESCs and ecDNAs are seldom linked. Here, we provide the first comparative review of ecDNAs and ESCs, and highlight the reasons why these molecules are more closely related than once assumed
Fabrication and characterization of boron-terminated tetravacancies in monolayer hBN using STEM, EELS and electron ptychography
No full textTetravacancies in monolayer hexagonal boron nitride (hBN) with consistent edge termination (boron or nitrogen) form triangular nanopores with electrostatic potentials that can be leveraged for applications such as selective ion transport and neuromorphic computing. In order to quantitatively predict the properties of these structures, an atomic-level understanding of their local electronic and chemical environments is required. Moreover, robust methods for their precision manufacture are needed. Here we use electron irradiation in a scanning transmission electron microscope (STEM) at a high dose rate to drive the formation of boron-terminated tetravacancies in monolayer hBN. Characterization of the defects is achieved using aberration-corrected STEM, monochromated electron energy-loss spectroscopy (EELS), and electron ptychography. Z-contrast in STEM and chemical fingerprinting by core-loss EELS enable identification of the edge terminations, while electron ptychography gives insight into structural relaxation of the tetravacancies and provides evidence of enhanced electron density around the defect perimeters indicative of bonding effects
Responding proportionately to the COVID-19 pandemic in UK long-stay inpatient pediatric wards
No full textThe COVID-19 pandemic had a significant impact on how healthcare and social care were delivered in the United Kingdom. Infection prevention and control measures were introduced in all settings to prevent transmission within, to, and from them. A case study of an inner-city pediatric surgical ward in late autumn 2020 was created for this chapter to explore the ethical and legal dimensions of the impact of these measures on patients, their families, and healthcare staff. Material for the case study and the impacts discussed were informed by research carried out during the pandemic. As part of a project entitled When Pandemic and Everyday Ethics Collide: Supporting Ethical Decision-Making in Maternity Care and Pediatrics During the COVID-19 Pandemic, a National Health Service (NHS) Reset Ethics Project. Data was collected from NHS staff and service users between July 2020 and September 2021. The chapter discussion reflects research findings related to the loss of community on hospital wards and the effect this had on staff and parents. The chapter also addresses how parental visiting restrictions may have eroded parents’ rights to family life and the loss of their right to parent. Finally, the chapter explores the negative effects on all concerned of staff being responsible for policing restrictions on the ward. The measures were, on balance, proportionate, given the staff’s duty of care, but the costs were probably more significant than originally envisaged. This should be reflected in future planning measures and in greater stakeholder involvement
Dynamic Protein Structures in Solution:Decoding the Amide I Band with 2D-IR Spectral Libraries and Machine Learning
No full textDevelopment of a Novel 7-DOF Position-Orientation Decoupled Microsurgical Robot with Motorized Instruments for Microvascular Anastomosis
No full textThis work introduces a novel compact 7-degree-of-freedom (7-DOF) microsurgical robot with position-orientation decoupling capacity for microvascular anastomosis. The proposed system employs a modular architecture combining a proximal displacement platform for 3D small-stroke translation and a distal compact remote center of motion (RCM) mechanism for wide-range orientation adjustment. This design meets the workspace requirements for microvascular anastomosis, requiring extensive orientation adjustments with minimal positional movement and reducing the system footprint. The parasitic motion reverse self-compensation method has been developed for motorized surgical instruments, effectively reducing operational resistance to improve precision. Theoretical analysis has been performed on both the RCM mechanism and motorized surgical instruments, and kinematics-based parameter optimization and data-driven calibration have been conducted to enhance superior performance. A prototype has been constructed, and its experimental validation demonstrated that the system achieved repeatability of 11.24 ± 2.31 μm (XY) and 12.46 ± 4.48 μm (YZ), and absolute positioning accuracy of 29.80 ± 12.27 μm (XY) and 37.02 ± 19.47 μm (YZ), meeting super-microsurgical requirements. Experiments that include needle-threading and stamen peeling tasks demonstrate the robot's superior dexterity and manipulation capabilities
Measuring progress in a new energy technology deployment: The case of small modular reactors
No full textSmall modular reactors (SMRs) are increasingly recognised as a promising solution to address the global energy trilemma of security, affordability, and sustainability. However, despite their potential, SMRs face systemic challenges that hinder their progression from conceptual designs to full commercial deployment. While existing literature identifies critical barriers individually, such as policy, regulation, financing, and supply chain development, integrated frameworks for assessing systemic progress remain scarce. This study addresses this gap by developing a novel, structured framework for evaluating the readiness of SMR deployment. Drawing on document analysis and 25 semi-structured expert interviews, a thematic analysis guided by abductive reasoning was conducted to identify the critical threshold criteria for the deployment of SMRs. A framework was then developed and operationalised across five core areas: policy support, licensing and regulatory readiness, financial viability, supply chain availability, and commercial readiness. The resulting framework offers policymakers, investors, and developers a practical tool for identifying bottlenecks, measuring systemic progress, and accelerating SMR deployment
General Surgery 4.0 – A Systematic Review of Extended Reality Interventions in General Surgery
No full textBackground
Surgery is a central component of healthcare but involves significant risks, with complications occurring in 16.4% patients, accounting for 7.7% of worldwide fatalities. “Surgery 4.0” or digitisation of surgery, has introduced extended reality (XR) technology, offering opportunities to enhance peri-operative care. This study explored the current uses of XR to improve outcomes for general surgery patients.
Method
A systematic search of MEDLINE, EMBASE, and Cochrane databases was performed in August 2024 to include studies using XR for pre-operative planning, navigation or patient experience for adult patients undergoing general surgery. Data on pre-operative planning, post-operative complications, patient experience, image segmentation and study reporting were presented using a narrative approach.
Results
The search returned 966 articles. 26 studies were included featuring 1142 patients. The most investigated procedure was liver resection (n = 11, 42%), with XR interventions showing significant reductions in length of stay, blood loss, operative time and complication rates. Improved outcomes were only seen for patients undergoing liver resection. For patient experience (n = 5, 19%), XR systems were shown to significantly improve anxiety, pain and mood scores. Most studies (n = 11, 73%%) utilised manual methods for image segmentation, costing up to €650 and taking 3-6 hours per model. Reporting of the XR technology, assessment and future development was variable.
Conclusion
The benefits of XR technology to improve patient outcomes in liver surgery are emerging but are yet to materialise in other general surgical procedures. Future research should focus on automatic image segmentation to improve workflow efficiency and innovation frameworks to generate robust evidence
Atmospheric Deposition of Local Mineral Dust Delivers Phosphorus to the Greenland Ice Sheet
No full textAerosol composition, size, and deposition rate determine the impact these particles have on cryosphere environments. Mineralogical, biological, and geochemical characteristics of aerosols collected over two years from the southwest Greenland Ice Sheet indicate that aerosols delivered via dry deposition and in snow primarily consisted of silicate minerals, with mean particle diameters of 1.01 ± 1.58 μm (2016) and 0.76 ± 0.87 μm (2017) for dry deposition and 2.4 ± 3.2 μm for dust delivered in snow (2017). The rare earth element signature of the delivered dust was typical of nearby Greenlandic lithologies, and combining this with other geochemical results and airmass history modeling indicated that the airborne mineral dust collected on-ice was likely from local emission sources, namely nearby proglacial plains. Dust and snow deposition rates were used to estimate phosphorus delivery to the ice surface at a rate of 1.2 mg·m–2·year–1, which could fuel estimated pigmented glacier ice algal cell abundances of 8.6 × 103 cells·mL–1, a value consistent with glacier ice algal bloom cell densities documented in the region. The eukaryotic communities in air and snow samples were dominated by algae and fungi, respectively, with both sample types also hosting various bacteria. These results suggest that the airborne transfer of glacier ice and snow algae may be a method by which fresh cryosphere surfaces become inoculated with these pigmented organisms. Collectively, these findings highlight the biogeochemical links between aerosols and the ice sheet surface, which have impacts on glacier ice algal growth and the corresponding surface ice albedo and melting