Strengthening System Research Articles

Intrados FRCM-strengthening of a masonry bridge: Experimental and analytical investigations

This paper will present the results of an experimental campaign aimed to study the structural behavior of solid clay brick masonry arch models strengthened at the intrados with Fiber Reinforced Cementitious Matrix (FRCM). The arch models’ peculiarities are: i) the presence of the haunching made of hydraulic lime mortar-based conglomerate, and ii) the geometry that reproduces a 1:2 scaled longitudinal section of a typical Italian railway single span bridge. The arch models are tested, imposing loading-unloading cycles to analyze the effectiveness of the strengthening system. The results are expressed in terms of failure mode, load carrying capacity and ductility, which shows the increase in the strength and displacement capacity of the strengthened model. Finally, limit analysis was performed to validate the experimental results and to assess the maximum fiber strain and the corresponding stress at the peak load.

Commentary: Strengthening System Readiness for Health Interventions: Lessons for Implementing Interventions and Implementation Support in Low-And Middle-Income Countries.

In low- and middle-income countries (LMICs), barriers such as low system readiness, contextual mismatches, and resource limitations impede effective implementation of evidence-based interventions. This commentary offers insights into overcoming these challenges with a case study of the PRISM project, designed to reduce behavioral and psychological symptoms of dementia in older adults living in Thailand. The case highlights how combining two evidence-based models - the Reducing Disability in Alzheimer's Disease clinical intervention and the Getting To Outcomes implementation science process enhances program success. Using interviews with stakeholders across various health system levels, we identify factors critical to successful program implementation: (1) integrating interventions into policy frameworks, (2) empowering local implementers, (3) fostering collaborative learning, and (4) adapting interventions to local contexts. The case demonstrates that building system readiness through local engagement and ownership is central to scaling up health programs in LMICs. This commentary's contribution lies in its emphasis on the role of implementation science as a vehicle for translating research into practice. It presents a practical, adaptive model for embedding interventions into routine health systems, thereby offering a pathway for successfully scaling up evidence-based programs in LMICs. Such findings provide lessons for overcoming barriers to implementation in resource-limited environments.

Shear Performance of RC Beams Strengthened with High-Performance Fibre-Reinforced Concrete (HPFRC) Under Static and Fatigue Loading.

This study experimentally assessed the shear performance of reinforced concrete (RC) beams strengthened with U-shaped High-Performance Fibre-Reinforced Concrete (HPFRC) under static and fatigue loading. Key parameters included HPFRC jacket thickness and beam shear span-depth (a/d) ratio. Five beams were tested under static loads to determine ultimate shear strengths, followed by fatigue tests on identical beams at 30-70% of ultimate shear strengths at 4 Hz. In static loading experiments, all the HPFRC jacketing proved effective, increasing the shear strength of RC beams by 95% to 130%. Although the strengthening system did not change the failure mode of the beams, the strengthened beams exhibited pseudo-ductile behaviour. As the a/d increased, the shear enhancement capability of the HPFRC jackets decreased. In fatigue loading experiments, all the HPFRC systems improved the fatigue life of RC beams. Specifically, in beams with an a/d ratio of 2.0, the fatigue life was extended from 75 cycles to a maximum of 951 cycles, while in beams with an a/d ratio of 3.5, it increased from 12,525 cycles to 48,786 cycles. In addition, a predictive model has been developed for the fatigue life of HPFRC/UHPFRC shear-strengthened beams, utilising the maximum fatigue load and the design's ultimate shear strength under static loading conditions.

Thin-layer Ultra-High-Strength Engineered Cementitious Composites (UHS-ECC) reinforced with small-diameter FRP bars for structural strengthening

This study proposed a novel strengthening system for reinforced concrete (RC) structures using a thin layer of Ultra-High-Strength Engineered Cementitious Composites (UHS-ECC) reinforced with small-diameter Fiber-Reinforced Polymer (FRP) bars. Experimental investigation, digital image correlation analysis, and numerical simulation were conducted to evaluate the flexural performance and failure mechanism of RC beams strengthened with 20-mm UHS-ECC layers and 3-mm FRP bars. It was found that the 20-mm UHS-ECC layer alone improved the load capacity of RC beams by 8.3 %, though with reduced deflection, whereas incorporating two 3-mm FRP bars increased load capacity by up to 40.4 %, without sacrificing deflection. Failure in all specimens was caused by concrete crushing; however, FRP-reinforced UHS-ECC layers mitigated early crack localization, significantly enhancing both strength and ductility. This study also revealed that cast-in-place FRP-reinforced UHS-ECC layers exhibited higher load capacity and could avoid ECC/concrete interfacial cracks compared to epoxy-bonded prefabricated layers. A three-dimensional finite element model was proposed for the strengthening system, and the flexural behavior was successfully predicted. It is revealed that the FRP-to-UHS-ECC bond had a marginal influence on performance, while the bond at the UHS-ECC-to-concrete interface significantly impacted flexural behavior. Remarkably, the small-diameter FRP bar achieved 75 % of its tensile strength at the ultimate stage. These findings underscore the potential of FRP-reinforced UHS-ECC layers as an effective solution for enhancing the mechanical and durability performance of RC structures.

Shear Strengthening of RC Beams Incorporating Post-Tensioned Bars and Engineered Cementitious Composite Reinforced with Palm Fronds

This paper investigates, experimentally and numerically, the shear strengthening of Normal Concrete (NC) beams using post-tensioning steel bars and Engineered Cementitious Composite (ECC) reinforced with chemically cured Palm Fronds (PFs). The benefits of strain-hardening ECC and the tensile strength of PFs cured with 6% wt Alkali NaOH solution beside post-tensioned bars have been employed herein. Seven full-scale Reinforced Concrete (RC) beams were fabricated and experimented with under three-point loading until failure. The test parameters include the strengthening technique, type, and configuration of the material used for strengthening. The strengthening process has been implemented through two techniques: Externally Bonded Reinforcement (EBR) and Near-Surface Mounted (NSM) Reinforcement. The strengthening materials have been configured and placed in horizontal, vertical, and inclined positions. The effectiveness of the strengthening methods has been evaluated by examining their cracking propagations, load-deflection responses, collapse modes, elastic stiffness, and absorbed energy. It was found that the proposed strengthening systems could significantly control the crack pattern and failure mode, and they could enhance the ultimate load amplitude up to 37% and 50% for NSM ECC with PFs and EBR post-tensioning steel bars, respectively. Nonlinear three-dimensional finite element models of the tested beams were developed and validated with the test data, where it was found that finite element models predict the structural performance of tested beams with a maximum error of only 2%.

Elevated Temperature Effects on FRP–Concrete Bond Behavior: A Comprehensive Review and Machine Learning-Based Bond Strength Prediction

Because of their improved properties, FRP composites are vastly used in the strengthening of aged concrete infrastructures. However, it has been observed that their performance is highly compromised when exposed to high temperatures, as expected during fire incidents, which critically affects FRP–concrete bond behavior, hence affecting the overall efficiency of the strengthening system. This paper critically presents the available literature concerning the degradation of bond strength between FRP systems with concrete substrates due to increased temperatures. Both analytical and numerical bond–slip models developed for the prediction of bond strength degradation under such conditions are reviewed. A generally confirmed fact is that exposure to high temperatures, especially those reaching glass transition temperature (Tg) for epoxy adhesives, leads to bond degradation. Therefore, cement mortar-bonded CFRP textiles display better performance in fire endurance. This present paper also utilizes machine learning algorithms for the prediction of bond strength under elevated temperatures based on an experimental database of 37 beams. The nonlinear relationships and variable interactions in the developed model provide a reliable method for the estimation of bond strength with reduced extensive experimental testing, where the critical role of temperature in bond behavior is identified. This paper emphasizes the use of advanced predictive models to ensure the durability and safety of FRP-strengthened concrete structures in thermally challenging environments.

Bond behaviour between near surface mounted CFRP and concrete members using magnetized bond agent under different temperature degrees

ABSTRACT In this investigation, the bond performance between CFRP and concrete in Near Surface Mounted (NSM) strengthening system using cementitious-based adhesive (CBA) was evaluated at different exposure temperatures. Two types of CBA were used (CBA-A and CBA-B) with and without magnetic water (MCBA-A and MCBA-B). Magnetic device with magnetic strength of 9000 Gauss was used to magnetise the water for 15 mins with a flow rate of 0.1 m3/hr. The bond efficiency was evaluated by performing single-lap shear tests for CFRP laminate embedded in concrete prisms as a near surface-mounted strengthening system. The bond between CFRP and concrete was tested under ambient and high temperatures. The heating regime involves the exposure of NSM CFRP/concrete samples to constant temperature (200°C) for 2 hrs, then the load was applied until failure. In comparison with control samples, an improvement of 40% in the load failure was achieved for specimens strengthened with CFRP using magnetised water in CBA. Within the MCBA samples, higher failure load was conducted for MCBA-B samples when compared with samples of MCBA-A since the latter contain primer in its compositions in which its properties deteriorate by high temperature. All tested samples showed similar failure pattern, which is slippage of CFRP.

Fire performance of CFRP-strengthened piloti-type columns with fire-resistant materials during standard fire exposure

This paper presents a numerical investigation into the fire endurance of carbon fiber reinforced polymer (CFRP)-strengthened columns, shielded with fire-resistant materials, in piloti-type reinforced concrete buildings. The strengthened column, equipped with a fire protection system, underwent exposure to the ASTM E119 standard time-temperature curve for a duration of 4 h. To comprehensively evaluate the thermal and structural performance of the strengthened column at elevated temperatures and substantiate the effectiveness of the fire protection system, a fully coupled thermal-stress analysis was conducted. The numerical modeling approach employed in this study was rigorously validated through previous experimental studies in conjunction with adherence to the ACI design guideline, specifically ACI 440.2R-17. Using the validated structural fire model, the thermal and structural behaviors of the RC column with an insulated CFRP strengthening system were investigated based on four key performance criteria: glass transition temperature, ignition temperature of polymer matrix, critical temperature of reinforcing bars, and the design axial load capacity at elevated temperatures. Furthermore, a comparative assessment of fire endurance was performed using diverse fire-resistant materials, including Sprayed Fire-Resistive Material (SFRM) and Sikacrete®-213 F, with insulation thicknesses ranging from 10 to 30 mm, during the 4-hour fire exposure period.

Deformation mechanism of Ni-based single crystal superalloy under ultrasonic surface rolling and subsequent thermal exposure

In present work, ultrasonic surface rolling (USR) is applied to DD6 Ni-based single crystal (NBSC) superalloys, and the thermal relaxation behavior of the pre-treated alloys are investigated at 650 °C. Combined with mechanical properties, the plastic deformation and recovery mechanisms of the hardened layers are revealed in detail. Results show that compressive residual stress amplitude of 1163 MPa, 75.1 % improvement of surface nano-hardness and 83.02 % reduction on surface roughness are achieved by USR. Both deformed layer thickness and slip density progressively increases with USR cycles, where initial octahedron {111}<110> slips transform to a mixture of octahedron {111}<110> and dodecahedron {111}<112> slips. Meanwhile, shear step length expansions form γ′ segment/γ terminal interface with superlattice extrinsic stacking fault (SESF) on 1¯11, which may have inferior energy threshold for γ dislocation invasions than primary ones through shortening mean free path. Also, this drives γ′/γ solute mingling to induce tortuous interfaces. While dislocation proliferation dominates γ channel hardening, the γ′ hardening derives from planar fault strengthening and net system energy augmentation. During thermal exposure, surface integrities of USRed DD6 are strongly degraded, attributable to slip trace elimination and local γ′ coarsening. Thermal exposure further compels the γ dislocation to migrate towards γ′ segment across γ′ segment/γ terminal interface. Then, they are probably consumed to motivate solutes to phase boundary to reshape the γ′ morphologies through interface rearrangements under the assistance of γ dislocation network. The orientation transformation of SESF on 1¯11 to 010 and the mixture of SESF and superlattice intrinsic stacking fault on 1¯11 are thought to be possible manipulated mechanisms for γ′ coarsening, significant impairing the work hardening of alloy due to interfacial coherency deterioration. This paper could provide guidance for USR strengthening designs of NBSC.

Learning interventions in the WHO Eastern Mediterranean region: supporting Member States to get prepared for better response to health emergencies in the region.

The Eastern Mediterranean Region (EMR) faces numerous public health risks caused by biological, chemical, man-made, and natural hazards. This manuscript aimed to assess the multifaceted interventions and strategies used to strengthen the EMR's preparedness capacities to respond properly to current and upcoming health emergencies. To address these challenges, it is crucial to implement comprehensive and robust strategic risk assessments and health emergency preparedness frameworks. The World Health Organization (WHO) takes a risk-based approach, emphasizing the significance of all-hazards emergency management and the creation of national health risk profiles using the Strategic Toolkit for Assessing Risk (STAR). Furthermore, the International Health Regulations (IHR) Monitoring and Evaluation Framework (MEF) ensures continuous learning and capacity building among Member States, enhancing their ability to manage health emergencies effectively. Key components include State Party Annual Reporting (SPAR), Joint External Evaluation (JEE), After Action Review (AAR), Intra Action Review (IAR), and Simulation Exercises (SimEx). Moreover, initiatives like One Health, Emergency Care Systems, Safe Hospitals, and Public Health Emergency Operations Centers (PHEOCs) reinforce preparedness and response capacities. Risk communication and community engagement (RCCE) strategies play a pivotal role in disseminating timely information and fostering community resilience. Furthermore, the management of Chemical, Biological, and Radiological (CBRN) incidents remains a priority, necessitating collaboration between the public health and security sectors. This comprehensive approach aims to strengthen health systems, reduce risks, and improve emergency response capabilities throughout the EMR, thereby promoting global health security and resilience. The EMR is addressing public health challenges through frameworks like IHR-MEF, and RCCE. It is strengthening emergency care systems, ensuring safe hospitals, and establishing PHEOCs. Proactive measures to address CBRN events and collaboration are enhancing resilience. The inclusion of the One Health approach underscores the EMR's holistic strategy to address the health threats at the human-animal-environment interface. This demonstrates the EMR's commitment to global health security.

Enhancing the Flexural Capacity of Deteriorated Low-Strength Prestressed Concrete Beam Using Near-Surface Mounted Post-Tensioned Carbon Fiber-Reinforced Polymer Bar

This study aimed to address the critical issue of age deterioration in prestressed concrete (PSC) structures by investigating the strengthening of aged PSC structures using a near-surface mounted (NSM) post-tensioned carbon fiber-reinforced polymer (CFRP). A total of nine PSC beams, each with a length of 6.5 m, were fabricated for a four-point bending test. Various experimental parameters were taken into account, including the strengthening method, compressive strength of concrete in the PSC beam, and the prestressing force of the PSC beam. The results indicated that the NSM post-tensioned CFRP strengthening system proved more efficient when compared to the NSM non-post-tensioned CFRP strengthening system. The flexural capacity of the NSM post-tensioned CFRP strengthening system, under the deteriorated low-strength PSC beam, increased by up to 30.9% compared to the PSC reference beam. Additionally, the experimental results were compared to a finite-element analysis, and a parametric study was conducted to examine the material properties of the PSC beam. Consequently, the NSM post-tensioned CFRP strengthening system is expected to be an effective solution for addressing the issue of deteriorated low-strength PSC structures.

Flexural Behavior of RC Continuous Beams Strengthened by Cementitious Composite Materials

Due to their great strain capacity, high tensile strength, and ability to localize cracks, cementitious composite materials are beneficial for strengthening reinforced concrete (RC) members. This paper illustrates the application of cementitious composite materials in the form of precast thin layers to strengthen a double-spanned, full-scale RC beam. Both positive and negative zones were strengthened by the precast layer embedded into the concrete cover. The precast layers have a dimension of 20 mm in thickness and 150 mm in width as that of the substrate beam and were applied by two configurations: plain and reinforced layers. A ductile smooth steel sheet with 2 mm in thickness and 100 mm in width was used inside the reinforced precast layer. The composite action of the precast layer has mutual benefits; the embedded steel sheet localizes the cracks, while the surrounding cementitious composite materials protect the steel sheet from environmental impact. The experimental results showed that the strengthening system has a significant contribution to improve the failure mode and load-carrying capacity. The use of a plain precast layer caused a 6% increase in the ultimate load and a 33% enhancement in the moment redistribution ratio compared to the control beam (CB). Applying the strengthening system with reinforced precast layer shifted the failure mode from rupture failure in the precast layer to delamination without slippage in the embedded steel sheet and matrix, leading to the full tensile capacity of the precast layer. Besides, the yielded and ultimate loads increased by 34% and 41%, respectively, and maximum deflection increased by 36%. In addition, the beam's ductility increased by 36%, and the moment redistribution ratio was enhanced by 49% compared to the CB. Doi: 10.28991/CEJ-2024-010-09-05 Full Text: PDF

Flexural performance of narrow RC beams hybrid strengthened by TRECC plate

This paper proposes a novel hybrid strengthening method for narrow reinforced concrete (RC) beams that combines fiber-reinforced polymer (FRP) textile-reinforced engineered-cementitious composites (TRECC) plates along with a self-locking anchorage system. To evaluate the effectiveness of the proposed system, a series of four-point bending tests were conducted. These tests were designed to understand the effects of different strengthening methods, number of FRP grid layers, and TRECC bond lengths. The results showed that the hybrid strengthening system could effectively prevent the end debonding failure and impede the development of the intermediate debonding in the TRECC plate. Consequently, the TRECC plate can continue to carry the force, leading to a significant increase in strengthening efficiency, quantified as the increased ratio of the peak load of the strengthened beams to that of the reference beam. Furthermore, increasing the number of FRP grid layers can also improve the strengthening efficiency. However, longer TRECC bond length in hybrid strengthened beams will reduce the strengthening efficiency since the intermediate debonding will be more susceptible to occur; the design for appropriate bond length is necessary. Finally, an analytical model to predict the flexural capacity was derived and verified against the experimental results.

Novel strengthening method of signal tower using prestressed CFRP plates: Concept and behavior

A novel prestressed carbon fiber reinforced polymer (CFRP) plate strengthening method for signal towers was proposed. The proposed strengthening system incorporates a circumferential anchorage system, a support system, a column system, and CFRP plates. These elements synergistically interact with the tower, forming a self-balancing system. This integrated system can provide exceptional flexural capacity and reduce the lateral displacement of the tower under wind load. To validate this novel method, a series of four static load tests were conducted. The results showed that the initial stiffness of the strengthened tower with CFRP plate prestresses of 0, 200, and 400 MPa increased by 71.0 %, 113.8 %, and 113.8 % compared with the unstrengthened tower, respectively. Moreover, the CFRP plate slacking occurred later for the strengthened tower with higher CFRP plate prestress, and the stiffness of the tower after the CFRP plate slacking kept increasing as CFRP plate prestress increases. The results indicate that the prestressed CFRP plate strengthening method effectively improved the behavior of the tower under wind load. Moreover, the finite element method (FEM) was utilized to analyze the influence of the ratio of the circumferential anchorage system height to tower height, the ratio of the support system height to tower height, the ratio of the column height to tower height, the ratio of steel support length to tower diameter, the elastic modulus of the CFRP plate and CFRP plate prestress on the strengthening effect. Finally, a strengthening procedure was proposed according to FEM results and sensitivity analysis. The analysis findings can serve as a guide for designing the strengthening system.

Consistency of Bond–Slip Models in Simulating the Bond between ETS-FRP Bars and Concrete and the Shear Contribution of the Strengthening System

Consistency of Bond–Slip Models in Simulating the Bond between ETS-FRP Bars and Concrete and the Shear Contribution of the Strengthening System

Efficiency of FRPU strengthening of a damaged masonry infill wall under in-plane cyclic shear loading and elevated temperatures

This paper presents results of in-plane shear tests carried out at the ZAG laboratory in Ljubljana (Slovenia) on a RC frame with masonry infill made of clay blocks (KEBE OrthoBlock). The frame was loaded with constant vertical loads at the top of the columns and then by gradually increasing horizontal cyclic loads at the top beam level. Acquired forces and measured displacements allowed capturing hysteretic behavior for determination of dissipation energy. In addition, two Digital Image Correlation (DIC) systems, Aramis and the CivEng Vision, were used to visualize the behavior of the tested specimens, with an emphasis on computing locally required information about the behavior of highly deformable interfaces. Three types of specimens were tested in-plane: the reference specimen in form of plain RC frame, the reference specimen with constructed masonry infill without any strengthening and the specimen, previously damaged and then strengthened on both sides using glass mesh bonded to the infill and the RC frame using flexible adhesive made of polyurethane matrix (Glass Fiber Reinforced PolyUrethane - GFRPU system). The strengthening process, allowed the specimen to withstand additional cyclic loads, reaching a maximum drift of 3.6 % without serious damage disqualifying the structure from further exploitation. The GFRPU strengthening system was found to be highly effective in preventing infill collapse of damaged masonry infill wall during in-plane loading. Additionally, the results of extended thermal analysis of PU are presented as polymers are, in general, a material, poorly resistant to heat. However, the analyzed PU manifested stable properties up to 200 degrees Celsius, which makes this material promising in civil engineering applications at elevated temperatures.

Flexural Improvement of RC Slabs by FRP or Steel Using Different Strengthening Systems and Novel Anchoring Techniques

An experimental study on reinforced concrete one-way slabs strengthened by various methods and materials is introduced in this paper. Innovative anchorage procedures are presented and evaluated to prevent the strengthening elements with FRP system from de-bonding at the initial stages. Externally bonded embedded in concrete cover (EBECC) strengthening technology was proposed to save the fiber strips from being subjected to heat, degradation, and sabotage. Nine RC one-way slabs, including a control slab and eight strengthened slabs, were cast. One RC slab was strengthened using externally bonded embedded in concrete cover (EBECC), whereas the other tested RC slabs were strengthened using either externally bonded (EB) or near-surface mounted (NSM) procedures. The following test variables are used in this study: the proposed anchors, the area of steel, the kind of material utilized in NSM rods (carbon fiber reinforced polymer (CFRP), glass fiber reinforced polymer (GFRP), and steel), and the strengthening scheme. The ultimate and initial cracking loads, load–deformation response, cracking patterns, and failure behavior were recorded and discussed. Additionally, a comparison of the stiffness, ductility, and energy absorption of the examined slabs was reported. The strengthened slabs by various techniques showed a boost in flexural strength that varied from 67 to 107% compared to the control slab. In addition, RC slabs strengthened by NSM-CFRP bars showed a maximum flexural capacity when compared with slabs strengthened by GFRP and steel bars. Also, the results supported the superiority of a novel end anchorage. The ABAQUS program was employed to conduct a finite element analysis (FEA) employing 3-D geometries to compare and assess the numerical performance of the identical slabs under similar test settings. The results showed good agreement between the experimental and numerical findings.

What could improve surgical data system at health facilities with high surgical volume in Ethiopia?

BackgroundThe effective management of surgical and anesthesia care relies on quality data and its readily availability for both patient-centered decision-making and facility-level improvement efforts. Recognizing this critical need, the Strengthening Systems for Improved Surgical Outcomes (SSISO) project addressed surgical care data management and information use practices across 23 health facilities from October 2019 to September 2022. This study aimed to evaluate the effectiveness of SSISO interventions in enhancing practices related to surgical data capture, reporting, analysis, and visualization.MethodsThis study employed a mixed method, pre- post intervention evaluation design to assess changes in data management and utilization practices at intervention facilities. The intervention packages included capacity building trainings, monthly mentorship visits facilitated by a hub-and-spoke approach, provision of data capture tools, and reinforcement of performance review teams. Data collection occurred at baseline (February – April 2020) and endline (April – June 2022). The evaluation focused on the availability and appropriate use of data capture tools, as well as changes in performance review practices. Appropriate use of registers was defined as filling all the necessary data onto the registers, and this was verified by completeness of selected key data elements in the registers.ResultsThe proportion of health facilities with Operation Room (OR) scheduling, referral, and surgical site infection registers significantly increased by 34.8%, 56.5% and 87%, respectively, at project endline compared to baseline. Availability of OR and Anesthesia registers remained high throughout the project, at 91.3% and 95.6%, respectively. Furthermore, the appropriate use of these registers improved, with statistically significant increases observed for OR scheduling registers (34.8% increase). Increases were also noted for OR register (9.5% increase) and anesthesia register (4.5% increase), although not statistically significant. Assessing the prior three months reports, the report submissions to the Ministry of Health/Regional Health Bureau (MOH/RHB) rose from 85 to 100%, reflecting complete reporting at endline period. Additionally, the proportion of surgical teams analyzing and displaying data for informed decision-making significantly increased from 30.4% at baseline to 60.8% at endline period.ConclusionThe implemented interventions positively impacted surgical data management and utilization practice at intervention facilities. These positive changes were likely attributable to capacity building trainings and regular mentorship visits via hub-and-spoke approach. Hence, we recommend further investigation into the effectiveness of similar intervention packages in improving surgical data management, data analysis and visualization practices in low- and middle-income country settings.

Acute Respiratory Tract Infections in Pediatric Populations of Slum Areas: Navigating Challenges and Dynamics of Immune Responses.

The study presents a thorough examination of immune responses in pediatric populations within slum areas, specifically addressing respiratory infections. It explores the impact of slum conditions on respiratory health, detailing the epidemiology of infections, including common pathogens and environmental factors. The review delves into the etiology, clinical manifestations, and challenges associated with viral respiratory infections, co-infections, and complications in slum environments. The discussion extends to immune responses in pediatric respiratory infections, emphasizing unique challenges in diagnosis and treatment within slum areas. Prevention and intervention strategies are highlighted, encompassing vaccination programs, health education, and improving living conditions. It underscores the importance of targeted interventions, accounting for socio-economic factors, community-based strategies, and culturally sensitive approaches. It proposes the exploration of novel approaches and the development of vaccines tailored to prevalent respiratory pathogens in slum settings. Furthermore, the feasibility and impact of routine immunization programs, emphasizing accessibility, acceptance, and long-term sustainability are explored. It advocates strengthening primary healthcare systems, investing in healthcare workforce training, and improving diagnostic facilities. The potential of digital health technologies in enhancing surveillance, early detection, and the development of mobile applications or telemedicine platforms is discussed. In conclusion, the study emphasizes the multifaceted challenges faced by children in slum areas regarding respiratory infections, necessitating informed, interdisciplinary interventions. Addressing healthcare disparities, improving living conditions, and enhancing vaccination coverage are deemed crucial for mitigating the burden of respiratory infections. This review calls for collaborative efforts among researchers, healthcare professionals, policymakers, and community stakeholders to develop sustainable solutions for enhanced respiratory health in slum-dwelling pediatric populations.

Integrating PZT-based WP and EMI techniques with multi-criteria analysis for monitoring and assessment of mechanical properties of structural adhesives under curing

Structural adhesives are commonly employed as bonding agents in FRP strengthening systems. Measuring and assessing the mechanical properties of adhesives during the curing process is essential, as these properties directly influence the overall effectiveness of the strengthening system. This study investigated the development of mechanical properties in structural adhesives at various curing times using two PZT-based monitoring techniques, specifically wave propagation (WP) and electromechanical impedance (EMI) techniques. Two types of structural adhesives and two distinct curing temperatures (ambient temperature and mild temperature) were selected for examination. Throughout the adhesive curing process, both methods were utilized for monitoring. Subsequently, tensile tests were conducted to obtain the mechanical properties at different curing durations. The results demonstrate that monitoring indicators from both PZT-based techniques effectively captured the enhancement in adhesive performance during the curing process. Moreover, the tensile strength of the Sika and Carbon adhesives reached stability at ambient temperature after five and three days, respectively, while elevated temperatures accelerated the curing process. Furthermore, two Multi-Criteria Decision Making (MCDM) methods were employed to select monitoring indicators with the least deviation and the closest correlations with mechanical properties. These indicators have the potential to predict mechanical properties, potentially reducing the need for tensile tests.