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Management of Coronary Artery Perforations:A Stepwise, Case-Based Review From a High-Volume Center
Get PDFBackground Coronary artery perforation (CAP) is an uncommon but potentially life-threatening complication of percutaneous coronary intervention, occurring in 0.2% to 0.5% of routine cases and up to 3% of complex procedures such as chronic total occlusion interventions. Case Summary We report 9 consecutive cases of CAP managed at a high-volume tertiary center in the United Kingdom and involving varied coronary territories, mechanisms, and Ellis grades (I-V). All cases were initially managed with balloon tamponade. Definitive treatments included covered stents (n = 4), coil embolization (n = 2), and autologous clot embolization (n = 1), with no surgical bailout. Ellis class III perforations accounted for 4 cases, all requiring active intervention. Pericardial effusion occurred in 5 patients, with 3 patients requiring urgent pericardiocentesis. No in-hospital mortality was observed. Discussion CAP management should be guided by the severity of perforation, the anatomical site, and the patient's hemodynamics. A structured algorithm involving early balloon tamponade, lesion-specific device selection, and structured escalation can prevent mortality and surgical bailout
A techno-economic-environmental comparison of residential solar energy systems employing an up-to-date market analysis
No full textTo reduce primary energy consumption and emissions for households, this paper assesses the techno-economic-environmental performance of four residential energy systems based on a variety of solar technologies, i.e., solar photovoltaic (PV) panels, solar thermal evacuated tube collectors (ETCs), photovoltaic-thermal (PVT) collectors, and hybrid PV-ETCs, in comparison with grid-dependent systems. The primary innovative contribution of this study is the integration of realistic market-based cost models into the assessment framework, along with a comprehensive generalisation analysis to address the potential of solar-based systems across diverse contexts. An extensive market investigation on the current retail prices and quotations of components is first conducted, with up-to-date data integrated into the economic evaluation. The component sizes and operational control variables of the solar systems are optimised to achieve the minimum net present cost (NPC). A case study in Beijing shows that PV-, ETC-, PVT- and hybrid PV-ETC-based systems reduce the benchmark NPC of grid-dependent systems (USD 9890) by 34 %, 31 %, 44 % and 43 %, respectively, indicating that solar systems, especially cogeneration systems, are cost-effective in residential households. In contrast, ETC-based systems achieve the shortest payback period of 3.4 years and the highest internal rate of return at 42 %. Moreover, these solar systems reduce the benchmark carbon emissions of grid-dependent systems (9500 kg) by 35 %–74 %. The influence of local conditions and parameters on system performance is also investigated, showing that all solar systems can be profitable with annual solar irradiance of 900–2500 kWh/m2 and electricity tariffs of 0.05–0.10 USD/kWh. A generalised analysis of load characteristics indicates that PV-, hybrid PV-ETC-, and PVT-based systems are optimal for householders with low domestic (<40 L/day), medium (40–200 L/day), and high hot water loads (>200 L/day), respectively. Finally, the economic feasibility of these systems is analysed in Beijing, Washington, London and New Delhi to span different global regions, revealing that all systems are profitable in these locations, and that hybrid PV-ETC-based systems in London achieve the highest NPC reduction of USD 20600.</p
Development and testing of strong-middle steel sections with enhanced buckling behaviour
No full textThis study experimentally investigates the compressive behaviour of steel hollow sections with a specified strength heterogeneity along their length achieved through localized Induction Heat (IH) treatments. By converting the ferrite microstructure of S355 circular hollow sections (CHS) into coarse or fine martensite through IH, material yield strength can increase from 1.5 up to 2.4 times, respectively, in the area of IH application. The proposed strength-heterogenous steel sections, named Strong-Middle Sections (SMSs), are designed with higher material strength at mid-length and lower strength at the ends. As a result, SMSs can sustain higher compressive loads than conventional steel sections (CSSs) owing to their increased flexural resistance at mid-length. To validate the concept, column buckling tests were conducted to examine the effect of slenderness ratio, middle-to-end material strength ratio and the length of the strong mid-section in the proposed SMS design. Based on test data, SMSs achieved approximately up to 40 % higher buckling loads and up to 120 % greater post-buckling strength than the corresponding CSSs, displaying either a symmetrical or a novel asymmetrical buckling mode. Digital Image Correlation (DIC) measurements revealed a more unifrom distribution of strain demands along the length of the SMSs, indicating that larger portions of the steel section participated in plastic deformation. The novel deformation mechanism of SMS led to smoother post-buckling transitions and less abrupt drop of post-peak strength. Although approximate, EN 1993–1–1 well estimates the yielding strength of SMS by shifting the location of the first-fibre yielding from the mid-length of the section to the end regions of the section. However, this approach appears to underestimate the maximum compression load achieved by SMSs, which was found to exceed the axial plastic resistance of the section at low slenderness ratios
Projecting compound flood hazards induced by tropical cyclones in Southeast China using MRI-AGCM3-2-S climate model
Get PDFMany low-lying coastal areas are highly vulnerable to compound flooding induced by tropical cyclones (TCs), which often generate storm tides, intense rainfall, and elevated river discharge simultaneously. Despite their significant impacts, the spatiotemporal changes and future hazards of TC-induced compound flooding under climate change remain poorly understood for many coastal regions. This study presents a novel integrated hazard assessment framework to evaluate TC-induced compound flooding across 60 cities in Southeast China, one of the world’s most TC-prone regions. Using TC tracks detected from the MRI-AGCM3-2-S climate model combined with simulations using a cascade of hydrodynamic models, we simulate undefended compound flood hazards driven by rainfall, storm tides, and river discharge under the current climate (1960–2014) and future projections under the SSP585 scenario (2015–2099). Our results indicate that, according to simulations using the MRI climate model, more than half of the 60 cities in Southeast China are projected to experience more severe TC-induced compound flooding under future climate scenarios. Shanghai, in particular, is projected to experience the largest increases in compound flood hazard, with the maximum flood volume rising by 83.6%. Our analysis of flood drivers shows that flooding in 6 cities transition from single driver to compound-dominated type. For instance, Suzhou and Nantong are projected to shift from rainfall-dominated flooding to compound-dominated flooding. A detailed case study of Shanghai indicates a significant spatial expansion of areas dominated by compound flood drivers, with the flood-prone area fraction projected to increase from 60.6% to 78.1% under future climate scenario. These findings highlight the growing hazards of TC-induced compound flooding in Southeast China due to climate change. We recommend future research to increase the robustness of the approach by including multiple climate models and collect data on flood defenses to further refine the model outcomes
Lifting polynomial representations of SL<sub>2</sub>(<i>p</i><sup>r</sup>) from <i><sub>p</sub></i> to ℤ/<i>p</i><sup>s</sup>ℤ
No full textWe describe all of the irreducible polynomial pSL2(pr) representations which lift to (ℤ/psℤ)SL2(pr) representations for s > 1, observing that they almost never do. We also show that two related indecomposable pSL2(pr) representations cannot be lifted to ℤ/psℤ representations for s > 1
The Experiences of People From Ethnic Minority Backgrounds Living in Care Homes—A Qualitative Systematic Review
Get PDFThe experiences of people from ethnic minority backgrounds living in care homes—A qualitative systematic review.Aim: Despite the increasing need for older people from ethnic minority backgrounds to be able to access good quality, culturally competent care home provision, globally, there is an absence of literature exploring care home residents' perspectives. This study conducted a systematic review, identifying and synthesising qualitative evidence, which explored the experiences of residents', and their families, from ethnic minority backgrounds, who live in care home settings.Design: A qualitative systematic review.Nine electronic databases, MEDLINE, Nursing and Allied Health, CINAHL, ASSIA, AMED, Sociological Abstracts, PsycINFO, Web of Science, SCOPUS, were systematically searched for research published after 2005 until 2025.Review Methods: This systematic review of qualitative studies was conducted in accordance with The PRISMA 2020 (Preferred Reporting Items for Systematic Reviews and Meta-analyses) statement. Studies were appraised for quality based upon validated critical appraisal tools from the Joanna Briggs Institute. Qualitative data were extracted and synthesised using reflexive thematic analysis.Results: Sixteen studies were identified from the international literature that explored care home experiences from the resident's and families' perspectives. Three key themes were extrapolated: Patter, which includes how cross-cultural communication skills and language affect care experiences; Place, which includes the care home environment, the multi-ethnic environment, and quality of care; and Person, which encompasses the individual's culture, values, beliefs, food, and family.Conclusion: There is limited literature from the UK and low-to-middle income countries exploring care home residents' perspectives on care provision. Key components of culturally competent care include culturally sensitive communication, adaptable environments that support residents' chosen lifestyles, and inclusive, family-centred approaches to living well.Impact: For nurses within the adult social care sector, to recognise the need for further research, education, and policy initiatives aimed at enhancing the care home provision for people from ethnic minority groups.Patient or Public Contribution: There was no patient or public contribution
Enabling highly conductive charged oxide inversion layers through hot corona discharge
Get PDFSilicon solar cell manufacturing is dominated by cell architectures that rely on a high-temperature energy-intensive diffusion process to introduce dopants. Such doped layers lead to substantial Auger recombination losses. Charged oxide inversion layer (COIL) solar cells eliminate the need for high-temperature diffusion and highly doped surface layers by incorporating charge in a surface dielectric to form an inversion layer emitter beneath the semiconductor-dielectric interface. The success of the COIL design hinges on achieving a sufficiently high dielectric charge to produce highly conductive inversion-layer emitters. In this work, we develop a new “hot-corona discharge” technique to facilitate the charge drive-in via a process integrating corona charging and thermal annealing into a single step. We show the process is effective in creating an n-type inversion layer on p-type silicon wafers, yielding increases in carrier lifetime and reductions in emitter sheet resistance. The temperature (330–430 °C) and time (30–1020 s) dependence of this new hot-corona approach is studied, demonstrating careful control over charge density. By optimising the process against temperature and ion drive-in cycles, we achieve the highest positive charge concentration reported on a SiO2/Si interface of >4.0 × 1013 q/cm2. With the ability to incorporate such high charge density, a low sheet resistance and highly conductive inversion layer can be formed. This represents a significant step forward in the attempt to replace the diffused emitter technology with a low-temperature alternative, enabling high-efficiency inversion-layer solar cells with reduced thermal budget and intrinsic losses.</p
Radiation effects of CERN-PS 24 GeV/c protons in silicon strip sensors, evaluated with ATLAS18 ITk strip sensor test structures
Get PDFTest structures from the ATLAS18 ITk strip detector wafers were irradiated with 24 GeV/c protons. These test structures were positioned at various angles with respect to the proton beam. Blocks of G10 material were placed in front of these test structures to study the effect of scattering of primary protons on the received particle fluence. The results confirm that both the incidence angle of the beam and scattering significantly influence the actual fluence to which the samples are exposed. Miniature strip detectors, first irradiated with protons, were also irradiated with reactor neutrons, to a combined fluence of φneq = 1.6 x 1015 cm−2. The combination of proton and neutron fluences matched the combination expected in the most exposed part of the strip detector in the ALTAS Inner Tracker (ITk). Good charge collection was measured confirming that the strip detectors are sufficiently radiation hard for successful operation to highest fluences expected at the HL-LHC
Solar-assisted high-temperature heat pumps to achieve off-grid zero-carbon heating in industrial parks
Get PDFIndustrial heating constitutes over half of global energy use, posing a major barrier to deep decarbonization. Solar energy, as a flexible and cost-effective renewable source, is ideal for off-grid power and heat in industrial parks. This study constructs and evaluates four solar-assisted pathways for delivering industrial heating by electrified heating: i) water-based photovoltaic-thermal with electric boiler (PV/T-EB), ii) water-based PV/T with high-temperature heat pump (PV/T + HTHP), iii) PV/T-direct-expansion heat pump with HTHP (PV/T-DXHP + HTHP), and iv) PV-powered air-source heat pump with HTHP (PV-ASHP + HTHP). A techno-economic assessment considering local weather, heat demand and system costs was conducted for four representative cities: Birmingham, Shanghai, Mumbai, and Los Angeles. Results show that heat pump-based systems have 50–67 % lower levelized cost of heat (LCOH) compared to PV/T-EB. Global climate and economic boundary conditions guide the selection of specific SAHP solutions. Water-based PV/T-HTHP and PV-ASHP + HTHP show the lowest LCOH (/kWh) for 100–160 °C heating in moderate solar zones. Although PV/T-EB shows the highest LCOH under current cost conditions, it may become favorable by 2035 (with a projected 30 % cost reduction) in areas with poor solar resources for high-temperature (>140 °C) applications, where it can also achieve lower life-cycle CO2 emissions compared to solar-assisted heat pump (SAHP) systems. For higher temperature processes (>200 °C), additional technologies beyond the scope of this study will be required. In summary, this article highlights the overall advantages of SAHPs in global heating scenarios within the 80–160 °C range by comparing SAHPs, EBs, and gas boilers (GBs) in terms of performance, economics, and carbon emissions, thereby providing a theoretical reference for addressing the decarbonization of ∼30 % of industrial heating demand.</p
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