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With the addition of electrically conductive steel or carbon fibers, Ultra-High-Performance Concrete (UHPC) possesses an intrinsic self-sensing capability. This opens up the possibility of combining the resilience and sustainability of UHPC with the development of self-sensing solutions for structural applications. In this study, the self-sensing behaviour of a proprietary nano-engineered UHPC material subjected to tension was investigated. To assess the self-sensing performance of the material, bulk resistivity measurements were used on direct tension and pure flexure tests, while a novel wireless approach that operates on was used on out-of-plane bending tests. The wireless approach used alternate current (AC) measurements while the bulk resistivity methods were performed through direct current (DC) and the four-probe method. In both methods, the fractional change in resistance was correlated to the state of deformation. The disposition of the actual strain field was evaluated using Digital Image Correlation (DIC). It was found that in the case of direct tension and pure flexure, the fractional change of resistance was initially decreased up to the onset of strain localization, while it gradually increased in the post-peak range, where the separation of the localized crack gradually increased. In the case of the wireless approach using AC, the onset of cracking was successfully predicted with an abrupt increase in resistivity. The wireless strain-sensing approach also captured the Poisson's effect due to the loading. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to develop a healthy body image package for adolescents aged 12 to 15 years with body image dissatisfaction. Methods and Materials: The research method was a theory-driven deductive thematic analysis. In the qualitative content determination phase, the content, structure, and final form of the healthy body image package were developed using a five-step method based on theory-driven thematic analysis in line with Attride-Stirling's (2001) thematic network analysis. The statistical population included scientific texts related to a healthy body image and experts in the field of adolescent psychotherapy. Purposeful sampling was employed based on the content relevance of 30 scientific texts to strategies for promoting a healthy body image in adolescents until theoretical saturation was reached. Additionally, 6 expert psychotherapists with more than 10 years of experience in adolescent psychotherapy participated. Data were analyzed using theory-driven thematic analysis. Findings: The findings indicated that the content of the healthy body image package included four main concepts: perceptual strategies training, emotional strategies training, cognitive strategies training, and behavioral strategies training. The content validity of the educational package was equal to 1. Conclusion: According to the results of the present study, it is suggested that this educational package be taught to managers, teachers, and counselors to reduce body image dissatisfaction in adolescents. [ABSTRACT FROM AUTHOR]

The rapid, inexpensive, and on-site detection of bacterial contaminants using highly sensitive and specific microfluidic sensors is attracting substantial attention in water quality monitoring applications. Cell-imprinted polymers (CIPs) have emerged as robust, cost-effective, and versatile recognition materials with selective binding sites for capturing whole bacteria. However, electrochemical transduction of the binding event to a measurable signal within a microfluidic device to develop easy-to-use, compact, portable, durable, and affordable sensors remains a challenge. For this paper, we employed CIP-functionalized microwires (CIP-MWs) with an affinity towards E. coli and integrated them into a low-cost microfluidic sensor to measure the conductometric transduction of CIP–bacteria binding events. The sensor comprised two CIP-MWs suspended perpendicularly to a PDMS microchannel. The inter-wire electrical resistance of the microchannel was measured before, during, and after exposure of CIP-MWs to bacteria. A decline in the inter-wire resistance of the sensor after 30 min of incubation with bacteria was detected. Resistance change normalization and the subsequent analysis of the sensor's dose-response curve between 0 to 109 CFU/mL bacteria revealed the limits of detection and quantification of 2.1 × 105 CFU/mL and 7.3 × 105 CFU/mL, respectively. The dynamic range of the sensor was 104 to 107 CFU/mL where the bacteria counts were statistically distinguishable from each other. A linear fit in this range resulted in a sensitivity of 7.35 μS per CFU/mL. Experiments using competing Sarcina or Listeria cells showed specificity of the sensor towards the imprinted E. coli cells. The reported CIP-MW-based conductometric microfluidic sensor can provide a cost-effective, durable, portable, and real-time solution for the detection of pathogens in water. [ABSTRACT FROM AUTHOR]