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Experimental game-based learning:A serious game experiment in purchasing and supply management
No full textTo better prepare higher education graduates for the early stages of their careers, universities aim to bridge the gap between classroom teaching and the skills demanded by industry, particularly in the field of procurement. Today, procurement professionals increasingly require specialised skill sets, rather than generalist education, to effectively fulfil their role-specific responsibilities. This study integrates experiential learning theory with game-based learning by presenting a synthesised model that unites both perspectives. Building on this model, a purchasing-specific game is employed to compare traditional lecture-based teaching with experiential game-based learning, focusing on purchasing skills as well as cognitive and affective learning outcomes. The effectiveness of the game-based approach is examined through a group comparison experiment, contrasting students who played the game (N = 202) with those who attended conventional lectures (N = 135). The findings indicate that the game effectively develops purchasing and supply management (PSM) skills relevant to professional practice. Moreover, students evaluated the game as a highly positive learning experience, and it outperformed traditional lecturing in most skill-related, cognitive, and affective outcomes, ultimately leading to improved examination performance. For educators, the study highlights the design and implementation of the serious game, its pedagogical implications, and directions for future research in procurement education and beyond.</p
Deep learning–based temporal MR image reconstruction for accelerated interventional imaging during in-bore biopsies
No full textPurpose: Interventional MR imaging struggles with speed and efficiency. We aim to accelerate transrectal in-bore MR-guided biopsies for prostate cancer through undersampled image reconstruction and instrument localization by image segmentation. Approach: In this single-center retrospective study, we used 8464 MR 2D multislice scans from 1289 patients undergoing a prostate biopsy to train and test a deep learning–based spatiotemporal MR image reconstruction model and a nnU-Net segmentation model. The dataset was synthetically undersampled using various undersampling rates (R ¼ 8, 16, 25, 32). An annotated, unseen subset of these data was used to compare our model with a nontemporal model and readers in a reader study involving seven radiologists from three centers based in the Netherlands. We assessed a maximum noninferior undersampling rate using instrument prediction success rate and instrument tip position (ITP) error. Results: The maximum noninferior undersampling rate is 16-times for the temporal model (ITP error: 2.28 mm, 95% CI: 1.68 to 3.31, mean difference from reference standard: 0.63 mm, P ¼:09), whereas a nontemporal model could not produce noninferior image reconstructions comparable to our reference standard. Furthermore, the nontemporal model (ITP error: 6.27 mm, 95% CI: 3.90 to 9.07) and readers (ITP error: 6.87 mm, 95% CI: 6.38 to 7.40) had low instrument prediction success rates (46% and 60%, respectively) compared with the temporal model’s 95%. Conclusion: Deep learning–based spatiotemporal MR image reconstruction can improve time-critical intervention tasks such as instrument tracking. We found 16 times undersampling as the maximum noninferior acceleration where image quality is preserved, ITP error is minimized, and the instrument prediction success rate is maximized.</p
A fully integrated ion trap with a single layer of Al<sub>2</sub>O<sub>3</sub> nanophotonics supporting light delivery from UV-NIR
No full textOptical clocks based on trapped ions are highly stable frequency standards with applications in navigation, fundamental physics tests, and chronometric geodesy. Hence, ion traps are a key component for ion-based quantum technology applications. To achieve greater scalability and laser pointing stability, it is crucial to integrate nanophotonics monolithically into ion trap architectures. Addressing and manipulating the ions requires wavelengths ranging from ultraviolet (UV) to near-infrared (NIR). In this contribution, we report on the design and characterization of a photonic integrating circuit for the optical addressing of Yb+ ions using a foundry-fabricated single-layer Al2O3 nanophotonic platform.</p
Energy efficiency of <i>Re</i>BCO degaussing systems for naval vessels
No full textShips are predominantly constructed from magnetic steel alloys, which exhibit magnetic permeabilities typically ranging between 100 and 300. As a result, the geomagnetic field around the ship becomes distorted, an effect known as its magnetic signature. This signature can be detected from a distance using active or passive magnetic field sensors. To avoid detection, navy ships are equipped with degaussing systems that render them largely magnetically invisible. These systems consist of coils distributed throughout the ship, generating magnetic fields that counteract its magnetic signature. Depending on the vessel’s size and geometry, degaussing systems typically require currents ranging from several hundred to several thousand amperes. Due to the ohmic resistance of conventional copper coils, their power consumption is relatively high. To reduce energy demand, copper cables can be replaced with superconducting ones. When cooled below their critical temperature Tc, superconductors exhibit negligible electrical resistance and can carry current densities 100 to 1000 times higher than normal metals. In this project, a ReBCO-based degaussing system was compared to a conventional one, focusing on the cooling power required versus the electrical power consumed. For small-scale ReBCO systems, cooling demands result in higher overall power consumption than conventional setups. However, as system size increases, ReBCO power consumption grows more slowly, leading to a crossover point. The exact ship length at which ReBCO becomes more energy-efficient depends on factors such as cryocooler efficiency, insulation heat leakage, and copper cable current density. Estimates suggest that for ships around 100 meters or longer, ReBCO degaussing systems become energetically more favorable
Compassion as a guiding framework for the implementation of digital mental health interventions:An interview study with clients and professionals
No full textBackground Digital mental health interventions are often described in terms of their contribution to cost-effectiveness or innovation. Instead, many clients and professionals in mental healthcare seem to value the human connection highly. To implement technology in ways that align with values held by clients and professionals, a value-based framework for technology use in mental healthcare could be promising. The current study explores whether values of clients and professionals in mental healthcare match a framework of compassion, and whether this framework could be a suitable foundation for the implementation of digital mental health interventions. Method We conducted semi-structured interviews with 5 (former) clients and 15 professionals in mental healthcare. Values of both clients and professionals were analyzed inductively, and deductively linked to a compassion framework. Professionals were asked whether their values were congruent with their organization’s approach to technology. We coded their answers as matches and mismatches, and described the themes developed in both categories. Results Values held by clients and professionals showed many connections with the compassion framework. Clients highly valued feeling heard and understood, humanity, and openness from the professional. Professionals highly valued helping people, personalization, and offering transparency. Examples of how technology use could enhance or detract from compassion according to participants were also produced. Professionals experienced a match with their values if they felt that their organizations focused the adoption of technology on the client’s autonomy or meeting treatment needs. They experienced a mismatch if they felt that their organizations were more focused on financial benefit or a technology push. Conclusion Compassion seems a promising framework for integrating technology in mental healthcare in value-sensitive ways.</p
Showcasing the Governance Assessment Tool as an “effective” contextual approach to water governance
No full textAddressing water challenges requires policies tailored to their governance context. The lack of such consideration is among the reasons why decentralisation, privatisation, and integrated water resources management have not achieved their intended outcomes. The Governance Assessment Tool (GAT) helps improve the effectiveness of water policies. GAT assesses how effective the implementation of water policies is and helps to develop policy recommendations to improve the effectiveness of the policy. As the purpose of this paper is to showcase the capabilities of GAT, we present its application in two different governance contexts (Iran and Mexico) to the European one where GAT was created. In our case selection, we focus on different challenges in water services (water supply and sanitation). In Iran, it is a single case study that assesses the groundwater policy, and in Mexico, it is a comparative case study of three sub-basins where the wastewater treatment plant policy is assessed. For each case, the results provide insights for improving policy effectiveness, such as the need for farmer participation in Iran and the need to enhance coordination by subnational governments in Mexico. These results showcase the GAT capability to assessing in-depth single case studies (Iran) and comparative analysis (Mexico). Moreover, GAT allows systematisation to navigate our understanding of complex challenges and provides a framework for academic and practitioners to understand the context and to propose tailored policies
Description of excitonic absorption using the Sommerfeld enhancement factor and band-fluctuations
No full textOne of the challenges of excitonic materials is the accurate determination of the exciton binding energy and bandgap from optical measurements. The difficulty arises from the overlap of the discrete and continuous excitonic absorption at the band edge. Many researches have modeled the shape of the absorption edge of such materials on the seminal formulation proposed by Elliott in 1957 (Phys. Rev. 108 1384-9) and its several modifications such as non-parabolic bands, magnetic potentials and electron-hole-polaron interactions. However, exciton binding energies obtained from optical absorption often vary strongly depending on the chosen ‘Elliott formula’. Here, we propose an alternative and rather simple approach, which has previously been successful in the determination of the optical bandgap of amorphous, direct and indirect semiconductors, based on the band-fluctuations (BFs) model. In this model, the fluctuations due to disorder, temperature or lattice vibrations give rise to the well known exponential shape of band tail states. The formulation results in an analytic equation for the fundamental absorption with 6 parameters only. To test it, the binding energy and optical bandgap of GaAs and the family of tri-halide perovskites (MAPbX3), X = Br , I , Cl , over a wide range of temperatures, are obtained by fitting the modified Elliott model. The results for the bandgap, linewidth and exciton binding energy are in good agreement with reports based on non-optical measurements. Moreover, due to the polar nature of perovskites, the retrieved binding energies can be compared with those computed with a model proposed by Kane (1978 Phys. Rev. B 18 6849). In the latter model, the exciton is surrounded by a cloud of virtual phonons interacting via the Frölich interaction. As a consequence, the upper bound for the binding energy of the exciton-polaron system can be estimated. These results are in good agreement with the optical parameters obtained with the proposed Elliott equation including BFs.</p
Performance Evaluation of Monolithic and Microservice Architectures for Natural Language Processing in Command and Control Applications
No full textThe success of Command and Control (C2) operations relies heavily on clear communication among participants, often under stressful and time-sensitive conditions that demand accurate decision-making. Examples of such operations include military engagements, reconnaissance missions, search and rescue efforts, and peacekeeping activities. The design of systems to support C2 is therefore challenging, as they must support structured communication and interaction means among participants. To address this, we developed a method called Method to Support Semantic Interoperability in Command and Control (MAISC2) to support C2, in which we have applied Natural Language Processing (NLP) and semantic techniques to pinpoint specific elements in sentences, thereby enhancing the participants' understanding of the C2 communications. Microservices Architecture (MSA) are known to offer potential benefits over MA, particularly in terms of scalability, independence, and maintenance. Furthermore, some NLP applications have already been developed using MSA, confirming these benefits. This paper presents a version of our system developed using MSA and compares it to its Monolithic Architecture (MA) counterpart. Our objective is to evaluate whether the benefits of adopting MSA, observed in other domains, also apply to C2 support systems based on NLP and semantic techniques, as exemplified by the MAISC2 method. Our results show that MA outperforms MSA in many scenarios; however, as the application load increases, MSA shows increasingly better performance. In particular, although MA had shorter processing and delivery times under normal conditions, MSA delivered better processing performance when handling significantly higher levels of concurrent activity.</p
Tuning the Shell Elasticity of Phospholipid-Coated Microbubbles via Palmitic Acid Doping
Get PDFPhospholipid-coated microbubbles have been developed as blood pool agents for contrast-enhanced ultrasound imaging. Tuning their acoustic response is key to expanding their use beyond contrast imaging alone. Here, we demonstrate that the shell elasticity of coated microbubbles can be controlled over 1 order of magnitude, from 0.5 N/m up to 4.5 N/m, by doping the native shell with palmitic acid. Characterization of shell elasticity as a function of bubble surface area via ambient pressure-controlled acoustic attenuation measurements revealed that the increased shell elasticity is confined to a narrow region around the equilibrium bubble surface area. Upon expansion of just 1–2% in bubble surface area, the surface elasticity rapidly drops to levels observed in non-PA-doped bubbles. The results further demonstrated that shell viscosity also varies with bubble surface area, which may further enhance nonlinear bubble dynamics. Dilatational surface tension curves, obtained by numerically integrating the elasticity curves, were used as input to a nonlinear bubble dynamics model based on a Rayleigh–Plesset-type equation. The results demonstrate that the controlled shell elasticity offered by this work allows microbubbles to be tuned in nonlinear acoustic response, significantly enhancing the sensitivity of their subharmonic response for a range of applications, including noninvasive pressure sensing.</p
A Robust Synthesis of Fluorosurfactants with Tunable Functionalities via a Two‐Step Reaction
Get PDFFluorosurfactant-stabilized microdroplets hold significant promise for a wide range of applications, owing to their biological and chemical inertness. However, conventional synthetic routes for fluorosurfactants typically require multiple reaction steps and stringent conditions, such as high temperatures and anaerobic environments. This complexity poses a significant limitation to the development of fluorosurfactant synthesis and its subsequent applications in droplet-based systems. In this work, a robust two-step synthesis of fluorosurfactants with tunable functionalities is presented. Microdroplets stabilized by these fluorosurfactants exhibit enhanced stability and biocompatibility. Notably, these fluorosurfactants facilitate the formation of nanodroplets that efficiently transport and concentrate fluorophores with high selectivity. Furthermore, it is demonstrated that colloidal self-assemblies with distinct structures can be engineered by modulating interactions between the fluorosurfactants and colloidal particles. The synthetic approach provides a strategy for the rapid production of functional fluorosurfactants under mild conditions, enabling droplet-based microfluidic techniques with applications in biology and material science.</p