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"The clock is ticking": (dis)orientations to ageing and end-of-life care in advanced capitalism and care directives
Get PDFSpecial Issue: ‘Future/Tense: A Sociology of Temporal (Dis)Order’This article engages Italian migrant experiences and enactments of futurity to problematize neoliberal anticipatory approaches to ageing and care. Stepping beyond the focus on atomized and agentic individuals and a singular imagined future defined by notions of advancement and progress, sistemazione (home, future, and security) offers ways of building alternative and relational futures within times and spaces of shared precarity. We draw on ethnographic fieldwork and interviews with Italian migrant families living in Adelaide, and a critical analysis of objects as “orienting devices,” to consider how a family heirloom, a 26-face handmade Italian clock made from the physical remnants of World War II, offers new ways of imagining care within spaces of ruin.Tanya Zivkovic, Simone Marin
Effects of Notches on Breakdown Pressures and Fracture Evolution in Hydraulic Fracturing
No full textPublished online: 19 July 2024Sustainable ore extraction in cave mining heavily relies on the effective fragmentation or caveability of the orebody. Since cave mining offers substantial benefits, it has gained popularity after preconditioning was introduced to help improve caveability. Therefore, hydraulic fracturing serves as a vital technique for risk management and cave stimulation. The increased rock competency and high stress levels in the rock mass around the orebody significantly influence fracturing and, thus, cavability processes. In order to improve the çefficiency of preconditioning by hydraulic fracturing to specific parts of the non-caving or poorly caving formations, the use of notches as artificial flaws offers an influence on the directionality of fracture propagation; this approach also has the potential to decrease the necessary breakdown pressures, thereby lifting limitations on the design and mechanical capabilities of fracturing campaigns and reducing required breakdown pressures, which could improve hydraulic fracturing capabilities. In this study, we studied the effects of notches on hydraulic fracturing performance under varying stress conditions. A number of hydraulic fracturing experiments were conducted using different notch quantities and spacings. Notches were created parallel to the axis of confining stress, and specimens were then subjected to constant axial loads of 40 MPa under varying confining pressures ranging from 5 to 40 MPa. A supplementary 3-D discrete element method using 3DEC was performed, and the results were compared with the hydraulic fracturing experiment. The 3DEC models incorporated Darcy's Law to describe fluid flow through fractures, and the Mohr–Coulomb softening yield criterion was used to simulate failures on predefined surfaces, providing a thorough hydro-mechanical coupled solution. We found that introducing notches can effectively reduce the pressures needed for fracture initiation and growth. Moreover, with appropriate spacing, fracture direction can be controlled. This knowledge, combined with the use of numerical modelling, has advanced our understanding of fracture behaviour and the influence of notches on propagation paths under different stress regimes. These findings could potentially revolutionise the field of hydraulic fracturing, making it more efficient and sustainable.Ben Powlay, Murat Karakus, Khalid Amrouch, Chris Cheste
Transforming Plastics to Single Atom Catalysts for Peroxymonosulfate Activation: Axial Chloride Coordination Intensified Electron Transfer Pathway
No full textFirst published: 05 January 2025Transforming plastics into single-atom catalysts is a promising strategy for upcycling waste plastics into value-added functional materials. Herein, a graphene-based single-atom catalyst with atomically dispersed FeN4Cl sites (Fe─N/Cl─C) is produced from high-density polyethylene wastes via one-pot catalytic pyrolysis. The Fe─N/Cl─C catalyst exhibited much higher turnover frequency and surface area normalized activity (Kac) compared with the Fe─N─C catalyst without axial Cl modulation. Both experiments and density functional theory (DFT) computations demonstrated that the axial incorporation of chloride fine-tuned the coordination environment of FeN4 sites and enhanced peroxymonosulfate (PMS) activation because of improved conductivity and modulated spin state. In situ, Raman, and infrared spectroscopic techniques revealed that PMS is activated by the Fe─N/Cl─C catalyst through an electron transfer process. The formation of a key PMS* intermediate at the Fe site effectively elevated the redox capacity of the catalyst surface to realize a fast degradation of diverse pollutants. The non-radical oxidation manner secures high selectivity toward target pollutants and high chemical utilization efficiency. A continuous operation in a column reactor also demonstrated the high efficiency and stability of the (Fe─N/Cl─C + PMS) system for practical water treatment.Shiying Ren, Yantao Wang, Lei Shi, Xin Xu, Shuang Zhong, Kunsheng Hu, Hongyu Zhou, Zhong-Shuai Zhu, Peng Zhou, Wenjie Tian, Jian Zuo, Jiabao Yi, Xiaohong Guan, Xiaoguang Duan, and Shaobin Wan
The Caring Life Course Theory: Opening new frontiers in care-A cardiac rehabilitation example
No full textFirst published: 16 July 2024Aim(s): To operationalize the Caring Life Course Theory (CLCT) as a framework for improving cardiac rehabilitation (CR) engagement and informing ways to address disparities in rural, low socio-economic areas. Methods: A secondary analysis of data collected from 15 CR programmes to identify CR patterns through the CLCT lens using a mixed-methods approach. All analytical processes were conducted in NVivo, coding qualitative data through thematic analysis based on CLCT constructs. Relationships among these constructs were quantitatively assessed using Jaccard coefficients and hierarchical clustering via dendrogram analysis to identify related clusters. Results: A strong interconnectedness among constructs: ‘care from others’, ‘capability’, ‘care network’ and ‘care provision’ (coefficient = 1) highlights their entangled crucial role in CR. However, significant conceptual disparities between ‘care biography’ and ‘fundamental care’ (coefficient = 0.4) and between ‘self-care’ and ‘care biography’ (coefficient = 0.384615) indicate a need for more aligned and personalized care approaches within CR. Conclusion: The CLCT provides a comprehensive theoretical and practical framework to address disparities in CR, facilitating a personalized approach to enhance engagement in rural and underserved regions. Implications: Integrating CLCT into CR programme designs could effectively address participation challenges, demonstrating the theory's utility in developing targeted, accessible care interventions/solutions. Impact: • Explored the challenge of low CR engagement in rural, low socio-economic settings. • Uncovered care provision, transitions and individual care biographies' relevance for CR engagement. • Demonstrated the potential of CLCT to inform/transform CR services for underserved populations, impacting practices and outcomes. Reporting Method: EQUATOR—MMR-RHS. Patient Contribution: A consumer co-researcher contributed to all study phases.Maria Alejandra Pinero de Plaza, Claire Hutchinson, Alline Beleigoli, Matthew Tieu, Michael Lawless, Tiffany Conroy, Rebecca Feo, Robyn A. Clark, Hila Dafny, Penelope McMillan, Regina Allande-Cussó, Alison A. Kitso
The United States' statecraft in the Pacific Islands
No full textThis chapter analyses the first country case study, that of the United States. In the context of its broader strategic competition with China, over the last five years, the US has considerably increased its focus on the Pacific Islands region. This chapter outlines the contours of the US's statecraft in the region since 2018 and argues that it has consisted of the deployment of tools statecraft in the diplomatic, developmental, and military realms. It concludes by arguing that, while the US has made a significant number of diplomatic gestures and has announced a range of substantial spending programs in the region, implementation of these announcements has been poor, primarily because domestic political divisions have delayed their passage through Congress. Therefore, while Pacific leaders have welcomed the US's re-engagement, the window for its statecraft to successfully build its reputation and relationships remains tight.Alan Tidwell, Joanne Walli
Upstream targeting for the prevention of atrial fibrillation: Targeting Risk Interventions and Metformin for Atrial Fibrillation (TRIM-AF)-rationale and study design
No full textPublished: 13 December 2024BACKGROUND: Despite advances in ablation and other therapies for AF, progression of atrial fibrillation (AF) remains a significant clinical problem, associated with worse prognosis and worse treatment outcomes. Upstream therapies targeting inflammatory or antifibrotic mechanisms have been disappointing in preventing AF progression, but more recently genetic and genomic studies in AF suggest novel cellular and metabolic stress targets, supporting prior studies of lifestyle and risk factor modification (LRFM) for AF. However, while obesity is a significant risk factor, weight loss and risk factor modification have not been successfully applied in a US population with AF. Metformin, a common drug that targets metabolic stress pathways, has demonstrated potential in reducing the burden of AF. METHODS: The Targeting Risk Interventions and Metformin for Atrial Fibrillation (TRIM-AF, NCT03603912) is a randomized clinical trial designed to examine reduction of AF burden and progression, targeting metabolic upstream therapies. This single center trial, at the Cleveland Clinic, is designed as a prospective randomized open-label blinded endpoint (PROBE) 2 × 2 factorial study of metformin extended release up to 750 mg twice daily and lifestyle and risk factor modification (LRFM) in patients with a cardiovascular implantable electronic device (CIED) that have had at least one ≥ 5-min episode of atrial fibrillation (AF) over the prior 3 months. Randomization is stratified by pacemaker vs. ICD and rhythm at enrollment (sinus rhythm/atrial paced vs. AF). CONCLUSION: TRIM-AF trial aims to determine if metformin, lifestyle, and risk factor modification (LRFM) reduce AF burden and its progression and assess whether combined therapy outperforms individual treatments. TRIAL REGISTRATION: URL: https://clinicaltrials.gov/ ; Unique Identifier: NCT03603912.Sojin Y. Wass, John Barnard, Hyun Su Kim, Han Sun, William Telfer, Taylor Schilling, Benico Barzilai, Dennis Bruemmer, Leslie Cho, Julie Huang, Ayman Hussein, Sangeeta R. Kashyap, Luke Laffin, Reena Mehra, Chris Moravec, Walid Saliba, Prashanthan Sanders, Steven Nissen, Niraj Varma, Jonathan Smith, David Van Wagoner, Mina K. Chun
Microplastic presence in dried and fresh fish from seafood markets in Sri Lanka
No full textContext: Microplastics have been found in aquatic ecosystems globally, including in many marine organisms. Despite this, understanding the occurrence of microplastics in seafood products prepared for human consumption has received less attention. Aims. This study aims to determine the abundance and type of microplastic in dried and fresh fish purchased from seafood markets. Methods: Four locally harvested species of anchovies and sardines were sampled from seafood markets across Sri Lanka. These pelagic species are popular seafood items and are commonly consumed whole. We analysed fresh (gastrointestinal tracts and whole body) and dried fish (whole body) under the microscope for microplastic presence (>38 μm, <5 mm), followed by polymer validation. Key results: Across all fish sampled (N = 215), 82.3% had microplastic (3.64 ± 0.26 microplastics per individual), with fibre-shaped pieces making up more than 95% of all microplastic particles. Overall, contamination was higher in fresh fish than in whole dried fish. And, acrylic resin was the most common polymer. Conclusions: Microplastics were found in nearly all fresh fish and almost half the dry fish from Sri Lanka, confirming the pervasive nature of microplastic contamination. Implications. Differences in contamination levels in popular seafood products demonstrate how preparation and consumption habits can influence microplastic intake.Nina Wootton, Vinuri Silva, Danielle Giuretis, Patrick Reis-Santos and Bronwyn M. Gillander
A review of mask fit testing data associated with protocols utilized in evaluating the efficacy of N95 masks for health care workers
No full textFirst published online July 20, 2024Background: Quantitative mask fit testing (QNFT) is the gold standard to confirm the correct fit of a N95/P2 mask to ensure health care workers protection from airborne viruses. Using the Occupational Safety and Health Administration (OSHA) guidance indicates a final fit test result is a cumulative score derived from manoeuvres within the OSHA protocol. The protocol-based manoeuvres mimic aspects of clinical care by health professionals and mask fit testing is conducted to provide protection from airborne viruses and pollutants within a care setting. Objective(s): To determine whether studies undertaking QNFT report the results of individual manoeuvres of the OSHA protocol. Methods: A comprehensive search strategy for the systematic review was developed to determine eligible studies, published between May 2011 and May 2021. Two researchers independently screened all full text articles retrieved and all disagreements were resolved through discussion. Results: The search found 557 studies. After removing 119 duplicates, 437 articles were reviewed based on title and abstract, 411 studies were excluded. Twenty-seven full text articles were assessed for eligibility, all were excluded for the following reasons: study did not report the results of the long or short OSHA protocol (12), study did not assess mask fit using the long or short OSHA protocol (10), article type (discussion/commentary/editorial) or wrong study type (1). Despite the use of very broad search terms no eligible studies were found and the result was declared an empty review. Conclusion: Internationally accepted QNFT protocols have a number of manoeuvres that reflect health care workers’ physical movements during the delivery of clinical care. Studies of mask fit testing appear to lack the reporting of outcomes for each manoeuvre with only the cumulative results being provided. This finding raises the need to understand potential risk from a mask leak during the delivery of clinical care as evidenced by failing a manoeuvre during mask fit testing. Further research is required to understand the importance of passing each mask fit testing manoeuvre and the relationship to airborne protection during the delivery of clinical care.Jody Hook, Louisa Sasko, and Sheree M Smit
Multifunctional Polymer Interphase with Fast Kinetics for Ultrahigh-rate Zn Metal Anode
No full textFirst published: 03 February 2025Polymer interphase on Zn anodes obviates dendrite growth and side reactions, however has drawbacks of slow kinetics. Here, a multifunctional polymer interphase with fast kinectics is reported, using poly(phenazine-alt-pyromellitic anhydride) (PPPA) as an electrolyte additive. PPPA, with linear π-conjugated structure and enriched polar pyridine (conjugated cyclic -C=N-) and carbonyl (C=O) groups, preferentially absorbs on the Zn anode to form a stable solid-electrolyte interpahse (SEI) layer in-situ. The PPPA SEI is efficient to block direct contact between water molecules and Zn anode, and regulate the interfacial solvation structure and Zn depostion. Importantly, the expanding π-conjugated structure of PPPA is shown to provide abundant 2D open channels for rapid Zn2+ transport, and the delocalized π electrons form a space electrostatic field to facilitate de-solvation and diffusion of Zn2+. As a result, the Zn metal anode with PPPA/ZnSO4 electrolyte exhibits high Coulombic efficiency of 98.3% at current density of 20 mA cm-2, and excellent cycle lifespan for over 2000 cycles (400 h) at current density 50 mA cm-2 and plating/stripping capacity of 5 mAh cm-2. The Zn||MnO2 full battery exhibited a discharge capacity of 74.4 mAh g-1 after 5000 cycles at the current density of 2000 mA g-1, demonstrating practical feasibility. It is concluded that judicious engineering of polymer additives and interphase will benefit the development of commercial AZIBs with fast kinetics for high-rate applications.Pan Xue, Can Guo, Wenbin Gong, Yuting Chen, Xiang Chen, Xiaoge Li, Jingyi Yang, Qichong Zhang, Kenneth Davey, Kaiping Zhu, Jianfeng Mao, and Zaiping Gu
Modeling of nonlinear systems: method of optimal injections
No full textIn this paper, a nonlinear system is interpreted as an operator F transforming random vectors. It is assumed that the operator is unknown and the random vectors are available. It is required to find a model of the system represented by a best constructive operator F approximation. While the theory of operator approximation with any given accuracy has been well elaborated, the theory of best constrained constructive operator approximation is not so well developed. Despite increasing demands from various applications, this subject is minimally tractable because of intrinsic difficulties with associated approximation techniques. This paper concerns the best constrained approximation of a nonlinear operator in probability spaces. The main conceptual novelty of the proposed approach is that, unlike the known techniques, it targets a constructive optimal determination of all 3p+2 ingredients of the approximating operator where p is a nonnegative integer. The solution to the associated problem is represented by a combination of new best approximation techniques with a special iterative procedure. The proposed approximating model of the system has several degrees of freedom to minimize the associated error. In particular, one of the specific features of the developed approximating technique is special random vectors called injections. It is shown that the desired injection is determined from the solution of a special Fredholm integral equation of the second kind. Its solution is called the optimal injection. The determination of optimal injections in this way allows us to further minimize the associated error