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Recent explosions have prompted researchers to investigate the vulnerability of civil structures, leading to an increased demand for blast-resistant buildings. Laminated glass (LG) panels in glazed facades boost resilience, yet understanding glass fragment interaction with interlayers remains incomplete. This paper presents an integrated experimental-computational study on strain localization in LG polymeric interlayers to accurately simulate their response, addressing this gap. Uniaxial tensile tests were performed on the polymeric interlayer materials polyvinyl butyral (PVB) and SentryGlas® (SG), commonly used in the design of LG in blast-resistant glazing systems. Digital image correlation was used to characterize strain localization within the material. The experimental results were used to calibrate material model parameters to be used in the modeling of LG systems. A three-network viscoplastic (TNV) material model for SG interlayer was calibrated using PolymerFEM software. Yeoh hyperelastic material model parameters were calibrated for the quasistatic response of PVB. A finite element computational model was developed using Ansys LS-DYNA software and validated with experimental data. The study results showcase finite element modeling's ability to accurately predict both the hyperelastic response of PVB and the post-peak large strain behavior of SG interlayer materials by 8% and 3.6%, respectively.

The study of blast loads on structures is important due to the potential of significant consequences in various scenarios. From terrorist attacks to industrial accidents, comprehending how structures respond to blast waves is critical for ensuring public safety and designing resilient structures. Studying these effects typically involves two main methods: free-field tests with live explosives and shock tube tests. Although shock tube testing offers certain advantages, both approaches are costly and demand significant space. This research aims to develop a cost-effective and straightforward technique for generating stress waves that closely replicate the progressive and spatial characteristics of free-field or shock tube blast waves. This method was designed to evaluate the dynamic response of laminated glass panels. The stress wave was generated by impacting a piston on the fluid inside a tube, which was connected to a fluid chamber. This setup produced impulsive loads that were distributed across a laminated glass test panel. Moreover, it was used to simulate the shock near filed explosions for a certain part of a structure. High-speed cameras were utilized to analyze the initial velocity of flying glass fragments. The apparatus successfully produced various blast waves and impulsive profiles for different drop weight heights. The initial velocities of randomly selected flying shards ranged from 3 m/s to 4 m/s.

Self-healing concrete presents an innovative and eco-friendly solution with the potential to reduce maintenance costs through self-activated crack repair. This study examined the effect of varying bacterial content across different environmental conditions. Additionally, the coupling effect between bacteria and steel fiber to enhance the mechanical and physical properties at different ages has been investigated. Bacillus Sphaericus (B. Sphaericus) was incorporated into the concrete at concentrations of 2 × 109 (CFU/ml), and different bacterial percentages selected utilizing calcium lactate as a nutrient source. Bacterial content of 0.0 %, 0.25 %, 1.0 %, and 2.5 %, cured in both fresh water and magnesium sulfate water solution, were tested to examine concrete behavior in harsh environments. Additionally, steel fibers at volume fraction percentages (Vf%) of 1.0 % and 1.5 %, along with 1.0 % bacterial content, were tested to highlight their combined effect. Tests were conducted at different ages to measure compressive, tensile, and flexural strengths. In addition, SEM and EDS analyses for cracked and uncracked specimens were performed. The results showed a significant increase in the long-term compressive, tensile, and flexural strengths at 180 days by 47 %, 80 %, and 50 %, respectively, with a bacterial content of 2.5 %. Moreover, the incorporation of steel fibers, 1.0 % and 1.5 % content, in the bacterial concrete resulted in a long-term compressive strength increase at 180 days by 45 % and 55 %, respectively with 1.0 % bacterial content, compared to 15 % and 27 % for 0 % bacteria. Curing in sulfate-rich water, concrete specimens exhibited increasing compressive strength at 180 days from 47 MPa for 0 % bacteria to 77 MPa with 2.5 % bacteria content. Despite lower initial strength of 29 MPa at 7 days, bacterial incorporation led to significant strength improvements, highlighting effective self-healing even in aggressive curing environments.

This paper described the use of photovoice within design thinking to empathise with patients’ challenges and co-create ideas on asthma management in Singapore. A one-day workshop was organised and conducted in Singapore by SingHealth Polyclinics to discuss the challenges and enablers of good asthma care and ideate innovations to address the issues discussed. The workshop was conceptualised based on the Stanford’s d: school Design Thinking Process: 1. empathise, 2. define, 3. ideate, 4. prototype, and 5. test, focussing on the first three stages. Empathise stage was executed by having two patients share their challenges and enablers of good asthma care using photovoice. Define and ideate stage were accomplished through the multidisciplinary team discussion, with the patient going to every group to allow them to seek clarifications and opinions on ideas. The study findings were summarised based on the Empathise, Define and Ideate stages. Thirty-seven healthcare providers attended—9 doctors, 14 nurses, 4 pharmacists, 3 clinical service, 3 medical students and 4 research staff. Participants’ feedback was collected via an online feedback form to evaluate the effectiveness of an innovation workshop. More than 90% of participants strongly agreed or agreed that they could generate ideas to improving asthma care, the workshop helped drive innovation, and the use of photovoice helped them empathise with patients challenges. A design thinking framework can be used for innovation workshops. Photovoice is a useful method for understanding the problems faced by patients. A multidisciplinary team format with patient involvement was highly favoured.

Verifying and validating explosion-resistant design models are challenging tasks due to the difficulties in accurately capturing the failure evolution within a setup influenced by the combined effects of fluid–solid interactions (FSI), blast waves, fragmentation, and impact. Curtain wall system, as a key structural component, is widely used in various types of buildings for its aesthetic appeal and weather protection. Hence, optimizing the explosion-resistance of such systems is necessary to improve building safety. In this work, we develop computational procedures that can be used to enhance the design of blast-resistant structures. This paper focuses on studying a representative component (e.g., window panels) from a typical curtain wall system, as well as a small-scale modeling of shock tube testing. For that, the material point method (MPM) simulations are verified against the finite element method (FEM) simulations, and the computational results are validated against shock tube testing. The work objective is to evaluate the simulation fidelity of explosion responses in several case studies. The first case study demonstrates how the MPM captures damage and fragmentation in a typical confined explosion event involving FSI, thus, providing an improved physical description compared to the FEM. The second case study qualitatively compares the MPM’s ability to simulate the shock tube response with experimental observations. Since the second study validates that the MPM solution is qualitatively consistent with the experimental data, the MPM model is then used in the third case study to establish an FEM model that could capture the same physics. This FEM model can be scaled up to model field experiments. The fourth case study involves the development of an FEM model for a representative curtain wall system component, which is validated against experimental results and then scaled down and employed to validate a corresponding MPM model. The proposed procedure provides a feasible approach to verifying and validating explosion-resistant designs for more general cases.

Abstract Background Digital technology tailored for those with limited health literacy has the potential to reduce health inequalities. Although mobile apps can support self-management in chronic diseases, there is little evidence that this approach applies to people with limited health literacy. We aimed to determine the acceptability of a self-management app in adults living with asthma and have limited health literacy and the feasibility of delivering the intervention and assessing outcomes. Methods We recruited eligible adults from the Klang Asthma Cohort registry in primary care for a 3-month mixed-method study plus a 2-month extended observation. We collected baseline data on socio-demography, health literacy and asthma control level. The outcomes of the intervention were assessed at 1- and 3-month: i) adoption (app download and usage), ii) adherence (app usage), iii) retention (app usage in the observation period), iv) health outcomes (e.g., severe asthma attacks) and v) process outcomes (e.g., ownership and use of action plans). At 1-month, participants were purposively sampled for in-depth interviews, which were audio-recorded, transcribed verbatim, and analysed deductively. Results We recruited 48 participants; 35 participants (23 Female; median age = 43 years; median HLS score = 28) completed the 3 months study. Of these, 14 participants (10 Female; median age = 48 years; median HLS score = 28) provided interviews. Thirty-seven (77%) participants adopted the app (downloaded and used it in the first month of the study). The main factor reported as influencing adoption was the ease of using the app. A total of 950 app usage were captured during the 3-month feasibility study. App usage increased gradually, peaking at month 2 (355 total log-ins) accounting for 78% of users. In month 5, 51.4% of the participants used the app at least once. The main factors influencing continued use included adherence features (e.g., prompts and reminders), familiarity with app function and support from family members. Conclusions An asthma self-management app intervention was acceptable for adults with limited health literacy and it was feasible to collect the desired outcomes at different time points during the study. A future trial is warranted to estimate the clinical and cost-effectiveness of the intervention and to explore implementation strategies.

Physical activity (PA) effectively prevents and treats non-communicable diseases in clinical settings. PA promotion needs to be more consistent, especially in busy primary care. Sports scientists have the potential to support PA promotion in primary care. The Physical Activity with Sports Scientist (PASS) programme is created to personalise PA promotion led by a sports scientist in a primary care clinic. A pragmatic randomised controlled trial with two parallel groups will be conducted at a family medicine clinic. Physically inactive participants aged 35–70 years who have type 2 diabetes mellitus, hypertension or dyslipidaemia will be invited. The control group (n=60) will receive usual care. The intervention group (n=60) will receive the PASS programme and usual care. The PASS programme will consist of a tailored PA prescription after the physician’s consultation at the first visit and monthly phone follow-ups. The primary outcome is the proportion of participants who have achieved the PA goal defined as aerobic activity (≥150 min/week of moderate to vigorous-intensity PA), muscle-strengthening activity (≥2 days/week of moderate or greater intensity) and multicomponent PA (≥2 days/week of moderate or greater intensity). Secondary outcomes are body composition and physical fitness. The primary and secondary outcomes will be measured and compared between the control and intervention groups at visit 1 (month 0: baseline measurements), visit 2 (months 3–4: follow-up measurements), visit 3 (months 6–8: end-point measurements) and visit 4 (months 9–12: continuing measurements). The study protocol was registered with the Thai Clinical Trials Registry.Trial registration number: TCTR20240314001.

Strengthening of composite beams is highly needed to upgrade the capacities of existing beams. The strengthening methods can be classified as active or passive techniques. Therefore, the main purpose of this study is to provide detailed FE simulations for strengthened and unstrengthened steel–concrete composite beams at the sagging and hogging moment regions with and without profiled steel sheeting. The developed models were verified against experimental results from the literature. The verified models were used to present comparisons between the effect of using external post-tensioning and CFRP laminates as strengthening techniques. Applying external post-tensioning at the sagging moment regions is more effective because of the exhibited larger eccentricity. In the form of an initial camber and compressive stresses in the bottom flange prior to loading, this reasonable eccentricity induces reverse loading on the reinforced beams, reducing the net tensile stress induced during loading. Using CFRP laminates on the concrete slab for continuous composite beams is more effective in enhancing the beam capacity in comparison with using the external post-tension. However, reductions in the beam ductility were obtained.

The fiber-reinforced polymeric (FRP) composite can be joined by adhesive bonding or mechanically fastening the composite element. Carbon fiber-reinforced polymers (CFRP) and glass fiber-reinforced polymers (GFRP) are the most common types of polymers. Mechanically fastened or bolted joints do not need treatments, and the surface temperature and other environmental effects such as humidity do not affect its strength. In this research, the previous research that describes the behavior of the composite bolted joint (CBJ) is presented and summarized including the modes of failure of the CBJ, and the experimental works that explain the bearing failure (BF) of the CBJ. In addition, the effects of bolt clamping force (BCF) and techniques that are used to simulate the progressive failure and damage in composite materials and finite element simulation works are surveyed.

Fatigue in steel–concrete composite beams can result from cyclic loading, causing stress fluctuations that may lead to cumulative damage and eventual failure over an extended period. In this paper, the experimental findings from fatigue loading tests on composite beams with various arrangements are presented. Fatigue tests were performed up to 1,000,000 cycles using four-point loading, encompassing various ranges of shear stress at a consistent amplitude. Additionally, the effects of external post-tensioning and the strength of the shear connection were investigated. Static tests were run until failure to assess the enduring strength of the specimens subjected to fatigue. The cyclic mid-span deflections, slippages, and strains were measured during the testing. Based on the experimental findings, it was found that the damage region that the shear studs caused in the concrete slab, which resulted in a reduction in stiffness within the shear connection, grew as the loading cycles increased, leading to an increase in residual deflections and plastic slippages. Controlling the longitudinal fatigue cracks in the concrete slab was largely dependent on the strength of the shear connection between the steel beams and concrete slabs. Moreover, the applied fatigue loading range affected the propagation and distribution of fatigue cracks in the concrete slab. The strains in different parts of the composite specimens were significantly reduced by applying the external post-tensioning. With no signs of distress at the anchors, the tendons displayed excellent fatigue performance.

Abstract Supported self-management reduces asthma-related morbidity and mortality. This paper is on a feasibility study, and observing the change in clinical and cost outcomes of pictorial action plan use is part of assessing feasibility as it will help us decide on outcome measures for a fully powered RCT. We conducted a pre–post feasibility study among adults with physician-diagnosed asthma on inhaled corticosteroids at a public primary-care clinic in Malaysia. We adapted an existing pictorial asthma action plan. The primary outcome was asthma control, assessed at 1, 3 and 6 months. Secondary outcomes included reliever use, controller medication adherence, asthma exacerbations, emergency visits, hospitalisations, days lost from work/daily activities and action plan use. We estimated potential cost savings on asthma-related care following plan use. About 84% (n = 59/70) completed the 6-months follow-up. The proportion achieving good asthma control increased from 18 (30.4%) at baseline to 38 (64.4%) at 6-month follow-up. The proportion of at least one acute exacerbation (3 months: % difference −19.7; 95% CI −34.7 to −3.1; 6 months: % difference −20.3; 95% CI −5.8 to −3.2), one or more emergency visit (1 month: % difference −28.6; 95% CI −41.2 to −15.5; 3 months: % difference −18.0; 95% CI −32.2 to −3.0; 6 months: % difference −20.3; 95% CI −34.9 to −4.6), and one or more asthma admission (1 month: % difference −14.3; 95% CI −25.2 to −5.3; 6 months: % difference −11.9; 95% CI −23.2 to −1.8) improved over time. Estimated savings for the 59 patients at 6-months follow-up and for each patient over the 6 months were RM 15,866.22 (USD3755.36) and RM268.92 (USD63.65), respectively. Supported self-management with a pictorial asthma action plan was associated with an improvement in asthma control and potential cost savings in Malaysian primary-care patients. Trial registration number: ISRCTN87128530; prospectively registered: September 5, 2019, http://www.isrctn.com/ISRCTN87128530 .

Laminated glass (LG) windows significantly enhance building safety due to their ability to retain shattered glass within the interlayer, but their susceptibility to failure under blast loading remains a concern. Compared with simplified models, detailed constitutive modeling is essential to evaluate these complex scenarios, as experimental investigation faces limitations in spatial and temporal resolutions. This study presents a robust model-based simulation approach for predicting the brittle failure response of glass in blast-resistant LG windows. An elasto-damage relation for glass (EDG) was integrated with the finite element model (FEM) to predict the blast response. Validation against shock tube testing results was performed to ensure the reliability of the FEM. Material parameters for the polymeric interlayer were obtained through dynamic experiments, enabling a reasonable representation of its constitutive behavior using the Johnson–Cook (JC) model. Additionally, a numerical parametric study was conducted to investigate how different glass types influence blast resistance performance. Tempered glass stood out for its blast resistance compared with annealed and heat-strengthened glass, displaying superior strength against blast loads. The Rankine-based elasto-damage description provides a more precise representation of the failure response than commonly used approaches. These findings contribute to advancing model-based simulation approaches for designing better blast-resistant LG windows, ensuring safer buildings.

Abstract Background Adjusting to life with a chronic condition is challenging, especially for people with limited health literacy, which is associated with low compliance with self‐management activities and poor clinical outcomes. Objective We explored how people with limited health literacy understand asthma and undertake self‐management practices. Design We adapted the arts‐based qualitative methodology Photovoice. Setting and Participants We sampled ethnically diverse adults with asthma and limited health literacy from four primary healthcare clinics in Malaysia. After a semistructured in‐depth interview, a subset of participants took part in the Photovoice component in which participants undertook a 2‐week photo‐taking activity and subsequent photo‐interview. Interviews, conducted in participants' preferred language, were audio‐recorded, transcribed verbatim, translated and analysed thematically. We used the Sorensen's framework (Domains: access, understand, appraise, apply) to describe participants' experience of living with asthma, what they understood about asthma and how they decided on self‐management practices. Results Twenty‐six participants provided interviews; eight completed the Photovoice activities. Participants with limited health literacy used various sources to access information about asthma and self‐management. Doctor–patient communication had a pivotal role in helping patients understand asthma. The lack of appraisal skills was significant and experiential knowledge influenced how they applied information. Self‐management decisions were influenced by sociocultural norms/practices, stigmatizing experiences, and available social support. Conclusion Locally tailored multilevel interventions (interpersonal, health system, community and policy) will be needed to support people with limited health literacy to live optimally with their asthma in an ethnically diverse population. Patient/Public Contribution Patients were involved in the study design, recruitment, analysis and dissemination.

ChatGPT, an artificial intelligence (AI) language model based on the GPT-3.5 architecture, is revolutionising scientific writing and medical research. Researchers employ ChatGPT for diverse tasks, including automated literature reviews, structured-outline generation and drafting/editing assistance. The tool adapts language for varied audiences, aids in citation management, supports collaborative writing and peer review and facilitates table/figure creation. While it enhances efficiency, concerns arise regarding ethics, bias, accuracy and originality. Transparent data sourcing and validation are crucial, as ChatGPT complements human efforts but does not replace critical thinking. Accordingly, researchers must uphold integrity, ensuring that AI-assisted content aligns with research principles. Acknowledgement of AI use in manuscripts, as recommended by the International Committee of Medical Journal Editors, ensures accountability. ChatGPT’s transformative potential lies in harmonising its capabilities with researchers’ expertise, fostering a symbiotic relationship that advances scientific progress and ethical standards.

Carbon fiber-reinforced polymer (CFRP) has many advantages as a construction/structural-strengthening material. However, there are still concerns regarding the long-term performance of these materials when used with reinforced concrete (RC) structures. Environmental conditions have an adverse effect on the behavior of CFRP and the bond between these sheets and concrete. Therefore, the durability of CFRP used for strengthening RC beams was evaluated under different environmental scenarios, including subjection to immersion in deicing agents, tap water, and saltwater, freeze-and-thaw cycles, and outdoor environmental changes. Laboratory tests were performed to examine the influence of these environmental scenarios on the bonding behavior between CFRP sheets and concrete in terms of deformations and modes of failure. Two types of test setups were performed in this study, namely pull-off shearing and three-point bending. Forty-two concrete prisms with CFRP were prepared and tested by using the pull-off shearing setup. It was observed that as the period of exposure increased, noticeable effects on the CFRP sheet as well as the bond stiffness were observed. Exposure to tap water had a greater impact than saltwater on the CFRP–concrete bond strength as well as the CFRP. In addition, eighteen notched concrete beams strengthened with an external CFRP were tested under three-point bending. The tap water exposure showed a 3.6% increase in the bond strength compared to the control specimen. However, the saltwater exposure showed a 10% increase.

Pre-stressed steel-concrete composite beams are widely used in bridges around the world. Loads during the service life of bridges may cause failure in the form of fracture in the studs near the ends of the bridge girders. The effect of stud failure on the residual static capacity and residual fatigue life of composite girders is not well investigated. Therefore, this study presents numerical investigations into the effects of the progressive failure of stud shear connectors on the residual static performance and remaining fatigue life of post-tensioned steel-concrete composite beams. The Finite Element (FE) model was validated using existing experimental work. Moreover, the effects of the progressive failure of stud shear connectors on the steel-concrete interface slippage, shear stress range, and compressive and tensile strains were investigated. The behavior of the composite girders in terms of the estimated fatigue life and residual capacity was inversely affected by the number of fractured studs. The AASHTO theoretical equation conservatively estimated the remaining fatigue life until 15% of the rows were removed and then the FE model predicted fewer remaining fatigue cycles than the theoretical equation. Until 15% of the rows were removed, the strengthened sample had a better response in terms of the stress range, tensile and compressive strains, and residual capacity. After that, both the strengthened and non-strengthened samples exhibited similar responses to the failure of studs. Subsequently, the positive effects of the post-tensioning vanish as the end studs fail. Therefore, designers should pay special attention to the ends of post-tensioned composite beams where the local failure of studs is expected.