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Utilization of a PFA-GGBS-Based Precursor in Geopolymer Concrete Production as a Sustainable Substitute for Conventional Concrete
Full text linkAwareness of environmental sustainability is driving the shift from conventional Portland cement, a major contributor to carbon dioxide emissions, to more sustainable alternatives. This study focuses on developing a geopolymer concrete by optimizing geopolymer concrete mixtures with various ratios of Ground Granulated Blast Furnace Slag (GGBS) and pulverized fly ash (PFA) as precursors, aiming to find a mix that maximizes strength while minimizing environmental impacts. The precursor was activated using a laboratory-synthesized silica fume (SF)-derived sodium silicate solution in combination with NaOH at a molarity of 10M. This study aims to find the optimal geopolymer concrete mix with a 0.55 water-to-binder ratio, a 0.40 alkali-to-precursor ratio, and a 1:1 sodium silicate to sodium hydroxide ratio. Ordinary Portland cement was used as the control mix binder (C), while the geopolymer mixes included varying GGBS-PFA compositions [CL0 (50% GGBS—50% PFA), CL1 (60% GGBS—40% PFA), CL2 (70% GGBS—30% PFA), CL3 (80% GGBS—20% PFA), and CL4 (90% GGBS—10% PFA)]. The engineering performance of the mixtures was assessed using slump, unconfined compressive strength, split tensile, and flexural strength tests in accordance with their relevant standards. Observations showed that GPC specimens exhibited similar or slightly higher strength values than conventional concrete using PC. In addition to strength, geopolymers have a smaller environmental footprint, consuming less energy and reducing greenhouse gas emissions. These qualities make geopolymer concrete a sustainable construction option that aligns with global efforts to reduce carbon emissions and conserve resources
The performance of a blended PFA/GGBS alkali-activated concrete using a silica fume-based activator
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The Impact of Understanding and Openness on State Mindfulness following a Brief Meditation: A Sham Controlled Study
Full text linkObjectives: There is growing concern among researchers and practitioners that misunderstanding of the central acceptance-based foundations of mindfulness, and/or a lack of openness to mindfulness, may prevent recipients from fully benefiting from an intervention. The current study was the first to experimentally investigate the impact of mindfulness understanding and openness on the efficacy of brief mindfulness meditation. Specifically, it investigated how both variables influence state mindfulness change following meditation. Method: Participants (n = 155) were randomly assigned to a sham or active mindfulness meditation condition. Pre-intervention measures included participants’ understanding of mindfulness (control vs. acceptance-based) and openness to mindfulness. State mindfulness levels were assessed before and after the intervention. Results: Participants in the active mindfulness condition reported significantly larger increases in state mindfulness than the sham, allowing further exploration of the primary research question. Higher openness was found to significantly predict increases in state mindfulness, while understanding was not. Conclusions: The current study provides preliminary evidence that higher openness to mindfulness practice leads to greater increases in state mindfulness following meditation. It also provides preliminary evidence that mindfulness understanding does not impact state mindfulness change following meditation. These findings emphasise the benefits of fostering open attitudes to mindfulness-based interventions (MBIs) to maximise treatment outcomes in clinical practice and suggest that the effectiveness of brief mindfulness meditation at eliciting mindful states is not compromised by misconceptions regarding its acceptance-based foundations. Major limitations discussed include placebo effects, suitability of the active and sham meditations, use of single item measures, and generalisability. Preregistration: This study was not preregistered.</p
Carotid artery dissection linked to intermittent apnoeic swimming: A case–control study
Full text linkInternal carotid artery (ICA) dissection is a rare and potentially devastating cause of cerebral ischaemia, initiated by an intimal tear or rupture of the vasa vasorum, that can lead to an intraluminal thrombus, vascular stenosis, occlusion, or dissecting aneurysm formation. Management is challenging due to its complex pathophysiology and non‐specific nature of symptoms. In this case–control study, we were able to document the clinical presentation and management of an ICA dissection in a hypertensive, 50‐year‐old male triathlete following an acute bout of intermittent apnoeic (pyramid breathing) swimming. He developed blurred vision in his left eye, ipsilateral headache, pulsatile tinnitus and later noticed left‐sided ptosis and pupil miosis consistent with Horner's syndrome, prompting specialist referral. Neuroimaging confirmed a dissection of the left ICA and incidental pseudoaneurysm of the distal right ICA. The patient recovered well due to a combination of pharmacological/dietary management of hypertension and graduated, structured return to physical activity and competition, culminating in significant re‐expansion of the ICA true lumen calibre. We also conducted a laboratory‐based, dry‐land, static swimming simulation in an age‐ and physical activity‐matched healthy male control. This demonstrated that exercise‐induced ICA shear stress was more exaggerated during dynamic apnoeic breathing compared to normal breathing, which, in the setting of the patient's hypertension, may have been a precipitating factor underlying ICA dissection. Collectively, these findings provide unique insights into the pathophysiology and management of this rare condition while highlighting the inherent risks associated with this mode of exercise training in susceptible individuals with hypertension
Living Wage Places as a Strategic Governance Tool: Strengthening Local Economies and Challenging In-Work Poverty
Full text linkThe UK’s Real Living Wage (RLW) serves as a strategic governance tool that establishes a boundary between in-work poverty and wages that provide a basic standard of living. While individual employer accreditation has been widely studied, less attention has been given to Living Wage Places, a scheme that accredits towns and cities based on clusters of accredited employers. As the result of a project exploring the feasibility of Newport, Wales, becoming a Living Wage Place, we conducted a case study analysis, statistical data review and geo-demographic assessment to make recommendations. The study situates Living Wage Places within broader discussions on the moral economy, social responsibility, and strategic governance, highlighting their role in reinforcing wage fairness and reducing in-work poverty at a local level. By examining how Living Wage Places can serve as a governance tool, this paper contributes to discussions on wage policy, local economic resilience, and the institutionalisation of fair work practices
Heart failure‐related elevation of carbohydrate antigen 125 identified by pre‐operative cardiopulmonary exercise testing
Full text linkSummary: Heart failure is a major peri‐operative risk factor associated with significant postoperative morbidity and mortality. Traditional biomarkers used in heart failure management include natriuretic peptides. Carbohydrate antigen 125 biomarker is well known to be elevated in ovarian cancer but can also be elevated in heart failure, particularly right‐sided heart failure and heart failure with preserved ejection fraction. We report the management of a 71‐year‐old woman with a presumed diagnosis of ovarian cancer based on imaging and an elevated carbohydrate antigen 125, who underwent cardiopulmonary exercise testing as part of the pre‐operative assessment. Exercise testing, despite being sub‐maximal, identified significant but asymptomatic heart failure. Surgery was deferred and cardiology‐led optimisation resulted in normalisation of her carbohydrate antigen biomarker, refuting her ovarian cancer diagnosis and avoidance of a major intra‐abdominal surgery. This case highlights the role of biomarkers, such as carbohydrate antigen 125, in heart failure treatment and the use of exercise testing in heart failure diagnosis and management. Cardiopulmonary exercise testing facilitated the identification of hidden comorbidities leading to better pre‐operative risk stratification, optimisation and collaborative decision making
Sustainability Coordinator Training: Successes, Challenges and Next Steps
Full text linkExecutive SummaryThe Sustainability Coordinator training programme, funded by Media Cymru in partnership with Severn Screen and Earth to Action, and supported by Ymddiried and Creative Wales, trained six people to become Sustainability Coordinators in the High-End television industry. Sustainability Coordinators can play a key role in fostering sustainable mindsets, behaviours, and practices across all phases of production, therefore having a broad and significant long-term impact. Over a two-month period in 2024, participants engaged in intensive training sessions, featuring leading industry speakers, held in studio classrooms throughout Wales.Through a series of in-depth interviews with participating trainees and training providers, and questionnaire responses from participating productions, below we provide a summary of the feedback received, in relation to the training itself, the successes and challenges encountered on production placements, and the wider discussion about the future of sustainability practice within TV and film production in Wales.The Media Cymru Sustainability Coordinator training programme successfully developed a cohort of skilled professionals, equipped to address sustainability challenges within the Film and Television sector in 2024. Future iterations of the programme must assess the capacity for new sustainability professionals, and ensure current participants receive adequate employment and development support.While an embedded sustainability approach adds significant value, its success relies on ongoing industry-wide commitment. Generating this commitment may involve budgeting for sustainability from the outset and mandating compliance for productions in Wales. With major broadcasters pledging net-zero goals, Wales has a unique opportunity to align national policy, leverage its trained workforce, and lead globally in sustainable TV and film production
Ultra-High-Order Laguerre-Gaussian Mode Output Based on Annular Pumping and Intra-cavity Lens
Full text linkThis letter presents an experimental study on generating ultra-high-order Laguerre-Gaussian (LG) modes in an Nd:YAG solid-state laser using annular pumping and an intracavity lens. The hollow structure of the annular pump beam effectively suppresses low-order modes, creating optimal conditions for high-order modes excitation. The intra-cavity convex lens enhances single-mode selection, enabling stable ultra-high-order petal-like LG 0,±l mode output. By adjusting the pump beam size and lens position, the highest angular indices l reached 375th order was achieved. This approach provides a novel method for high-order LG 0,±l mode generation in solid-state lasers, with potential applications in optical manipulation, optical communication, and related fields.</p