Search Results (235)

Antimicrobial resistance (AMR) constitutes a major global health challenge, driven significantly by inappropriate antibiotic use in human medicine. Despite the existence of evidence-based guidelines, variability in antibiotic prescribing persists, influenced by psychosocial factors, diagnostic uncertainty, patient expectations, and local prescribing cultures. Outpatient care, the setting in which most antibiotics are prescribed, is particularly affected by such challenges. Traditional top-down interventions, such as national guidelines, often fail to achieve sustained behavioral change among prescribers. In this comprehensive review, we provide an overview of the psychological and behavioral factors influencing antimicrobial stewardship (AMS) implementation, as well as describe a bottom-up project working to meet these challenges: the “Antibiotic Therapy in Bielefeld” (AnTiB) initiative. AnTiB employs a cross-sectoral strategy aimed at developing rational prescribing culture by means of locally developed consensus guidelines, interdisciplinary collaboration, and regularly held trainings. By addressing both the organizational and psychological aspects of prescribing practices, AnTiB has facilitated a harmonization of antibiotic use across specialties and care interfaces at the local level. The initiative’s success has led to its expansion within Germany, including through the creation of the AMS-Network Westphalia Lippe and the development of AnTiB-based national pediatric recommendations. These projects are all grounded in social structures designed to strengthen the long-term establishment of AMS measures. Our efforts underscore the importance of considering local social norms, professional network, and real-world practice conditions in AMS interventions. Integrating behavioral and social science approaches into outpatient antimicrobial stewardship—exemplified by the practitioner-led AnTiB model—improves acceptability and alignment with stewardship principles; wider adoption will require local adaptation, routine outpatient resistance surveillance, structured evaluation, and sustainable support. Full article

To address the difficulty in obtaining analytical solutions for the torsional vibration response of pile foundations in orthotropic layered soil foundations subjected to torsional excitation at the pile top, this study investigates a layered recursive algorithm based on the Hankel transform. An integral transformation method is employed to reduce the dimensionality of the coupled pile–soil torsional vibration equations, converting the three-dimensional system of partial differential equations into a set of ordinary differential equations. Combining the constitutive properties of transversely anisotropic strata with interlayer contact conditions, a transfer matrix model is established. Employing inverse transformation coupled with the Gauss–Kronrod integration method, an explicit frequency-domain solution for the torsional dynamic impedance at the pile top is derived. The research findings indicate that the anisotropy coefficient of the foundation significantly influences both the real and imaginary parts of the impedance magnitude. The sequence of soil layer distribution and the bonding state at interfaces jointly affect the nonlinear transmission characteristics of torque along the pile shaft. Full article

To further investigate the bond behavior between carbon fiber-reinforced polymer (CFRP) bars and ultra-high-performance concrete (UHPC) under monotonic loading, a finite element model was established in ABAQUS based on existing experimental data. The material parameters, constitutive models, and interface contact definitions were verified through numerical simulation. Utilizing this modeling strategy, 36 center-pull finite element models with dimensions of 150 mm × 150 mm × 150 mm were analyzed. By systematically varying the geometric parameters of the CFRP bars, the effects of surface configuration, bar diameter, and rib spacing on the bond performance between CFRP bars and UHPC were analyzed. The results demonstrate that uniform-ribbed bars exhibit the highest bond performance, followed by helical-ribbed bars, whereas dented-ribbed bars show the lowest bond strength. The ultimate bond strength decreases with increasing bar diameter. For uniform-ribbed bars, the optimal rib spacing is 1.2D (where D is the bar diameter), resulting in the highest peak bond strength. Full article

Changes in membrane lipid composition constitute a key bacterial resistance mechanism. In Staphylococcus aureus, phosphatidylglycerol undergoes lysine modification to form lysyl-phosphatidylglycerol, a cationic lipid that reduces the net negative surface charge and thereby enhances resistance to cationic antimicrobial peptides. In this study, we examined the influence of lysyl-PG on the membrane activity of three antimicrobial peptides with distinct physicochemical characteristics: LL-37, F5W Magainin II, and NA-CATH:ATRA-1-ATRA-1. Model membranes composed of phosphatidylglycerol and cardiolipin were supplemented with increasing molar fractions of lysyl-phosphatidylglycerol, and peptide–membrane interactions were characterized using Fourier-transform infrared spectroscopy. Membrane fluidity was evaluated through shifts in the symmetric methylene stretching bands, while changes in interfacial polarity were assessed via the carbonyl and phosphate asymmetric stretching bands. LL-37 induced pronounced disruption of anionic bilayers, an effect progressively attenuated by lysyl-phosphatidylglycerol, particularly within the hydrophobic core. F5W Magainin perturbed both hydrophobic and interfacial regions across a broader range of lysyl-phosphatidylglycerol concentrations, whereas NA-CATH:ATRA-1-ATRA-1 primarily targeted interfacial domains, with minimal disruption of acyl chain order. Increasing lysyl-PG content modulated the extent of bilayer disorder and dehydration at the hydrophobic–hydrophilic interface, with each peptide exhibiting a distinct interaction profile. Collectively, these findings provide mechanistic insights into lysyl-PG-mediated modulation of peptide activity and highlight the role of lipid remodeling as a bacterial defense strategy. Full article

Industrial park (IP) expansions in Mediterranean peri-urban areas can generate conflicts between economic development and agricultural heritage preservation. This paper develops a theoretically derived circular land use symbiosis model based on Hubs for Circularity (H4C) principles, using Fosso Imperatore IP in southern Italy as an illustrative case. This model proposes a transferable three-zone gradient design that enables the transformation of industrial–agricultural boundaries when combined with appropriate governance mechanisms and stakeholder engagement. Zone A concentrates vertical industrial development with rooftop agriculture; Zone B creates mixed agro-industrial interfaces; and Zone C enhances agricultural productivity through industrial resources. The model’s components (gradient zonation, temperature–cascade matching, and bidirectional resource flows) constitute generalizable design principles. When applied to Fosso Imperatore, where farmers oppose expansion that threatens culturally significant San Marzano tomato production, the model shows how 547 tons of organic waste could generate 87,520 m³ of methane, while industrial waste heat cascades from 150–200 °C to 25–40 °C of greenhouse heating across distances of 3 km. Implementation constraints include regulatory gaps and limited empirical data. This study operationalizes H4C through spatial design, showing how benefit-sharing mechanisms can transform stakeholder conflicts into collaboration. The model provides a replicable framework for Mediterranean contexts where industrial expansion encounters agricultural heritage. Full article

This paper presents a real-time smart mirror system combining multiple AI modules for multimodal health monitoring. The proposed platform integrates three core components: facial expression analysis, remote photoplethysmography (rPPG), and conversational AI. A key innovation lies in transforming the Moving Average rPPG (MA-rPPG) model—originally developed for offline batch processing—into a real-time, continuously streaming setup, enabling seamless heart rate and peripheral oxygen saturation (SpO₂) monitoring using standard webcams. The system also incorporates the DeepFace facial analysis library for live emotion, age detection, and a Generative Pre-trained Transformer 4o (GPT-4o)-based mental health chatbot with bilingual (English/Korean) support and voice synthesis. Embedded into a touchscreen mirror with Graphical User Interface (GUI), this solution delivers ambient, low-interruption interaction and real-time user feedback. By unifying these AI modules within an interactive smart mirror, our findings demonstrate the feasibility of integrating multimodal sensing (rPPG, affect detection) and conversational AI into a real-time smart mirror platform. This system is presented as a feasibility-stage prototype to promote real-time health awareness and empathetic feedback. The physiological validation was limited to a single subject, and the user evaluation constituted only a small formative assessment; therefore, results should be interpreted strictly as preliminary feasibility evidence. The system is not intended to provide clinical diagnosis or generalizable accuracy at this stage. Full article

This study examines the influence of friction at the specimen–bar interface on the macroscopic response of materials during dynamic compression tests using the split Hopkinson Pressure Bar (SHPB) under high-deformation-rate conditions. A mesoscale model is employed to simulate and compare results with experimental data, and a finite element model of cylindrical specimens with varying slenderness ratios is developed in Abaqus/Explicit. Numerical analyzes show that both specimen geometry and boundary conditions, particularly friction, have a decisive impact on the accuracy and reliability of SHPB measurements. A friction correction method based on barreling factor and plastic deformation demonstrates closer agreement with experimental observations than conventional approaches, revealing that the widely used Avitzur model may overestimate friction by 34–39%. The results highlight the importance of accurate friction correction and the selection of optimal specimen dimensions to minimize testing errors. These findings improve the precision of dynamic material characterization and support the development of more reliable constitutive models to predict material behavior across a broad range of strain rates. Full article

A layerwise laminate FE model capable of predicting the dynamic response of delaminated composite beams with piezoelectric actuators and sensors encompassing local non-linear contact and sliding at the delamination interfaces was formulated. The kinematic assumptions of the layerwise model enabled the representation of opening and sliding of delamination interfaces as generalized strains, thereby allowing the introduction of interfacial contact and sliding effects through constitutive relations at the interface. This realistic FE model, assisted by representative experiments, was used to study the time response of delaminated active sensory composite beams with predefined delamination extents. The time response was measured and simulated for narrowband actuation signals at two distinct frequency levels using a surface-bonded piezoceramic actuator, while signal acquisition was performed with a piezopolymer sensor. Four different composite specimens, each containing a different delamination size, were used for this study. Experimental results were directly compared with model predictions to evaluate the performance of the proposed analytical approach. Damage signatures were identified in both the signal amplitude and the time of flight, and the sensitivity to delamination size was examined. Finally, the distributions of axial and interlaminar stresses at various time snapshots of the transient analysis are presented, along with contour plots across the structure’s thickness, which illustrate the delamination location and wave propagation patterns. Full article

This paper investigates the influence of initial porosity and its evolution on the mechanical behavior of metallic materials manufactured by additive manufacturing (AM), using the Gurson model to predict the initiation and propagation of damage in specimens produced via Laser Powder Bed Fusion (LPBF). The methodology combines experimental uniaxial tensile tests, numerical simulations based on the Gurson model, and the parametric identification method (PIP) to calibrate constitutive parameters (${\sigma }_{y0}$, ${\sigma }_{\infty }$, $\delta$, $\xi$). The specimens, made of AlSi10Mg with different printing directions (horizontal and vertical) and porosity levels, were evaluated to determine the relationship between density, anisotropy, and mechanical properties. The experimental results revealed that vertical printing accelerates fracture due to the concentration of stresses at the interfaces between layers, while the numerical simulations, compared with the von Mises model, showed greater accuracy of the Gurson model in predicting damage in porous materials. The analysis of porosity evolution highlighted the impact of void size and spacing on coalescence and ductility. The proposed methodology was validated, establishing a useful approach for evaluating the mechanical behavior of materials manufactured by AM. This work contributes to the advancement of the design of lightweight and resistant components, with applications in sectors such as aerospace and automotive, and suggests directions for future studies, including the investigation of other alloys and dynamic loading conditions. Full article

Desert sand (DS) serves as a sustainable alternative to river sand in concrete production, delivering environmental and economic benefits. Furthermore, the durability of concrete structures in cold regions is severely affected by freeze–thaw (F-T) cycles. Therefore, this study employed a central pull-out test to examine the bond performance between desert sand concrete (DSC) and steel bars subjected to F-T cycles, considering the effects of the number of F-T cycles, DS replacement ratios (i.e., the replacement ratio of river sand by DS), and the type of reinforcement. The F-T cycle numbers tested were 0, 25, 50, and 75 cycles. The DS replacement ratios were varied at 0%, 20%, 40%, 60%, 80%, and 100%. The plain and threaded steel bars (PSBs and TSBs) were selected for the experiment. The results indicate a decrease in bond strength for both PSB and TSB specimens with increasing F-T cycle numbers. Regarding the DS replacement ratios, bond strength initially decreased, with an increasing replacement rate, then increased, and eventually reduced again. Notably, significantly improved bonding was observed for steel reinforcement in DSC containing 40% or 60% DS compared to plain concrete. Additionally, the bond strengths of PSB specimens were lower than those of TSB specimens under identical conditions. A calculation formula for the bond–slip characteristic was derived using statistical regression, which considered multiple factors. Eventually, a bond–slip constitutive model was developed for the interface between DSC and reinforced steel, showing a high degree of consistency with the experimental data. Full article

This study investigates the elastoplastic behavior of phenol formaldehyde/polyvinyl butyral matrix (70% PF/30% PVB) reinforced with Kevlar^® fibers through comprehensive in-plane tensile testing. Cyclic loading–unloading tests were conducted at a 100%/min strain rate using a universal testing system at room temperature on $\left(0_4\right)$, $\left({90}_4\right)$, and ${\left(\pm 45\right)}_s$ laminates. The experimental results revealed significant nonlinear hardening behavior beyond yield stress, accompanied by yarn stiffening effects during loading cycles. A novel elastoplastic constitutive model was developed, incorporating Hill’s yield criterion adapted for orthotropic materials and an isotropic hardening function that accounts for equivalent plastic strains and progressive yarn stiffening. Laminates with other stacking sequences were also tested and the accuracy of the predictions of the nonlinear behavior was assessed. In these laminates, delaminations took place and the model provided an overestimation of the stress–strain response. Since the model could not predict delamination onset and propagation, an adaptation of the model considering fully delaminated interfaces brought a lower bound of this response. Despite the limitations of the model, it can be used to provide reasonable limits to the stress–strain response of laminates accounting for plastic strains within plies. This study provides essential mechanical properties and constitutive relationships for designing Kevlar^® composite structures with tailored stiffness characteristics for impact-resistant applications. Full article

This paper presents the development and structure of a geospatial (work in progress), architectural heritage database designed to document, interpret, and valorize Second World War military fortifications in Sardinia. Currently hosting over 1800 georeferenced entries—including bunkers, artillery posts, underground shelters, and camouflage systems—the database constitutes the analytical core of an interdisciplinary research framework that interprets these remnants as a coherent wartime palimpsest embedded in the contemporary landscape. By integrating spatial data, archival sources, architectural features, conservation status, camouflage typologies, and both analog and digital graphic representations, the system operates as a central infrastructure for multiscale heritage analysis. It reveals the interconnections between dispersed military structures and the wider territorial fabric, thereby laying the groundwork for landscape-based interpretation and site-specific reactivation strategies. More than a cataloging tool, the database serves as an interpretive and decision-making interface—supporting the generation of cultural itineraries, the identification of critical clusters, and the design of adaptive reuse scenarios. While participatory tools and community engagement will be explored in a second phase, the current methodology emphasizes landscape-oriented reuse strategies based on the perception, spatial storytelling, and contextual reading of wartime heritage. The methodological synergy between GIS, 3D modeling, traditional drawing, and archival research (graphic and photographic documents) contributes to a holistic vision of Sardinia’s wartime heritage as both a system of knowledge and a spatial–cultural resource for future generations. Full article

Non-uniform corrosion cracking in reinforced concrete buildings constitutes a fundamental difficulty resulting in durability failure. This work develops a microscopic-scale multi-species electrochemical phase field model to tackle this issue. The model comprehensively examines the spatiotemporal coupling mechanisms of the full “corrosion-rust swelling-cracking” process by integrating electrochemical reaction kinetics, multi-ion transport processes, and a unified phase field fracture theory. The model uses local corrosion current density as the primary variable to accurately measure the dynamic interactions among electrochemical processes, ion transport, and rust product precipitation. It incorporates phase field method simulations of fracture initiation and propagation in concrete, establishing a bidirectional link between rust swelling stress and crack development. Experimental validation confirms that the model’s predictions about cracking duration, crack shape, and ion concentration distribution align well with empirical data, substantiating the efficacy of local corrosion current density as an indicator of electrochemical reaction rate. Parametric studies were performed to examine the effects of interface transition zone strength, oxygen diffusion coefficient, protective layer thickness, reinforcing bar diameter, and reinforcing bar configuration on cracking patterns. This model’s multi-physics field coupling framework, influenced by dynamic corrosion current density, facilitates cross-field interactions, offering sophisticated theoretical tools and technical support for the quantitative analysis, durability evaluation, and protective design of corrosion-induced cracking in reinforced concrete structures. Full article

Short fiber-reinforced polymer (SFRP) has been extensively applied in structural engineering due to its exceptional specific strength and superior mechanical properties. Its mechanical behavior under medium strain rate conditions has become a key focus of ongoing research. A comprehensive understanding of the response characteristics and underlying mechanisms under such conditions is of critical importance for both theoretical development and practical engineering applications. This study proposes an innovative three-dimensional (3D) multiscale constitutive model that comprehensively integrates mesoscopic fiber–matrix interface effects and pore characteristics. To systematically investigate the dynamic response and damage evolution of SFRP under medium strain rate conditions, 3D-printed SFRP porous structures with volume fractions of 25%, 35%, and 45% are designed and subjected to drop hammer impact experiments combined with multiscale numerical simulations. The experimental and simulation results demonstrate that, for specimens with a 25% volume fraction, the strain rate strengthening effect is the primary contributor to the increase in peak stress. In contrast, for specimens with a 45% volume fraction, the interaction between damage evolution and strain rate strengthening leads to a more complex stress–strain response. The specific energy absorption (SEA) of 25% volume fraction specimens increases markedly with increasing strain rate. However, for specimens with 35% and 45% volume fractions, the competition between these two mechanisms results in non-monotonic variations in energy absorption efficiency (EAE). The dominant failure mode under impact loading is shear-dominated compression, with damage evolution becoming increasingly complex as the fiber volume fraction increases. Furthermore, the damage characteristics transition from fiber pullout and matrix folding at lower volume fractions to the coexistence of brittle and ductile behaviors at higher volume fractions. The numerical simulations exhibit strong agreement with the experimental data. Multi-directional cross-sectional analysis further indicates that the initiation and propagation of shear bands are the principal drivers of structural instability. This study offers a robust theoretical foundation for the impact-resistant design and dynamic performance optimization of 3D-printed short fiber-reinforced polymer (SFRP) porous structures. Full article

Agentic AI systems, possessing capabilities for autonomous planning and action, show great potential across diverse domains. However, their practical deployment is hindered by challenges in aligning their behavior with varied human values, complex safety requirements, and specific compliance needs. Existing alignment methodologies often falter when faced with the complex task of providing personalized context without inducing confabulation or operational inefficiencies. This paper introduces a novel solution: a ‘superego’ agent, designed as a personalized oversight mechanism for agentic AI. This system dynamically steers AI planning by referencing user-selected ‘Creed Constitutions’—encapsulating diverse rule sets—with adjustable adherence levels to fit non-negotiable values. A real-time compliance enforcer validates plans against these constitutions and a universal ethical floor before execution. We present a functional system, including a demonstration interface with a prototypical constitution-sharing portal, and successful integration with third-party models via the Model Context Protocol (MCP). Comprehensive benchmark evaluations (HarmBench, AgentHarm) demonstrate that our Superego agent dramatically reduces harmful outputs—achieving up to a 98.3% harm score reduction and near-perfect refusal rates (e.g., 100% with Claude Sonnet 4 on AgentHarm’s harmful set) for leading LLMs like Gemini 2.5 Flash and GPT-4o. This approach substantially simplifies personalized AI alignment, rendering agentic systems more reliably attuned to individual and cultural contexts, while also enabling substantial safety improvements. Full article