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Wetlands:A blessing and a curse for human health
No full textAs populations are growing and need to be fed, wetlands become ever more essential for survival. Especially in arid and semi-arid environments where water is scarce, wetlands offer year-round water supplies and food security, providing life-support systems and promoting health in otherwise uninhabitable landscapes. Wetlands are extensively being used for agriculture, rendering them increasingly “unhealthy”, degraded and contaminated. The high dependence of users on wetlands and hence their exposure to contaminated water can subsequently cause problems in terms of health outcomes, given that wetlands are known sources of disease-causing microorganisms and invertebrates. Coupled with the degradation of water resources, wetlands can also become a health hazard, potentially exposing users to water-related infectious diseases. Thus, wetlands are not only a blessing but may also be a curse. The priority of the wetland-human health nexus on global reference frameworks and political agendas shows how essential it is to strike a balance between different wetland uses – that reduce the negative impacts and enhance the positive. This chapter showcases the benefits and threats that wetland use poses to human health, exemplified by evidence from empirical research in the Ewaso Narok Swamp in Laikipia, Kenya related to health risk assessments, health-related behaviour, health-seeking and health-related risk perceptions and local knowledge informing health-promoting wetland management strategies
Adopting circular strategies in medical device development:Mapping of methods along the engineering design process
Full text linkWith growing awareness of the environmental impact of medical devices, there is increasing recognition of the need to adopt circular strategies into their designs. This adoption involves redesigning existing devices and developing new devices, prioritizing efficiency and longevity of use through R-strategies such as Reduce, Reuse, Repair, and Recycle. As circular product design is still emerging, there is a need for practical guidance on integrating these R-strategies in medical devices. This study focuses on an inventory and mapping of methods (design methods) explicitly mentioned in the literature related to the (re)design of medical devices under the framework of circular economy principles. Through a systematic review of 28 papers, we identified 12 methods and mapped them to the corresponding R-strategies and phases of the generic engineering design process. Life cycle assessment (LCA) and material flow analysis were the two most frequently applied methods, with 12 and five citations, respectively, and tend to focus more on eco-efficient R-strategies. Nine out of the 12 identified methods focus on redesigning existing medical devices, primarily applied during the analysis and evaluation phases. By highlighting existing methods and their R-strategy applications in medical device (re)design, our findings aim to offer guidance to select and integrate methods that can support circular design practices throughout the design process of medical devices to drive the transition to a circular economy within healthcar
Pulsed laser deposition of ferroelectric gradient thin films
No full textThis thesis explores the use of off-center pulsed laser deposition (PLD) to fabricate ferroelectric thin films with controlled gradients in thickness, stoichiometry, and strain, enabling high-throughput investigation of growth-structure-property relationships in oxides. Using BaTiO3 (BTO) and Hf0.4Zr0.6O2 (HZO) as model systems, the work examines how process parameters and heterostructure design govern film morphology, strain, and ferroelectric switching. For BTO grown on SrTiO3 (STO), systematic variation of laser fluence and oxygen pressure revealed that pressure most strongly dictates morphology, stoichiometry, and lattice parameter gradients, while sufficient fluence is required to suppress Ba-rich island formation; together, these results establish thresholds for controlling oxygen vacancy and cation ratios. Off-center growth was then extended to heterostructures combining La0.7Sr0.3MnO3 (LSMO) with HZO, where thickness gradients enabled direct observation of both constant-voltage and constant-field coercive field scaling within a single film – respectively following JKD-like behavior (n ≈ –2/3) and near thickness-invariance (n ≈ 0) – demonstrating the critical role of measurement conditions and extrinsic effects such as leakage and imprint. Finally, BTO grown on STO-buffered silicon with either LSMO or La0.07Ba0.93SnO3 (LBSO) electrodes highlighted the interplay of plume-induced strain gradients, lattice mismatch, and domain orientation in determining ferroelectric switching. While BTO/LSMO showed stable polarization with significant imprint from asymmetric electrodes, BTO/LBSO exhibited strain-engineered lattice parameters but lacked measurable out-of-plane switching, suggesting that electrode geometry must be chosen according to the domain orientation. Across these studies, off-center PLD is validated as a powerful, scalable platform for mapping intrinsic and extrinsic ferroelectric behaviors, and the work ends with a brief note on the commercialization of PLD and the search for materials that can fully exploit the advantages of this technique
EMI Filter Design for High-Speed Inverter Drives in All-Electric Aircraft
No full textThis paper presents an integrated approach to EMI filter design for high-speed inverter drives in All Electric Aircraft (AEA) applications. Where traditional Electromagnetic Interference (EMI) filter design methodologies primarily focus on Conducted Emission (CE), this study incorporates lightning and inrush current requirements from DO-160G/ED-14G standards. Thus the performance is evaluated in time and frequency domain. This impacts the overall EMI filter design. Two filters were designed and analyzed: one following only CE design, the other incorporating lightning and inrush. Both were evaluated through simulation, showing comparable Insertion Loss (IL). However, the proposed design demonstrated a better transient mitigation due to a higher impedance input stage. Integrating lightning and inrush current effects early in the filter design process can lead to more compact solutions for aerospace applications, compared to traditional methods that consider those on the system level
Identifying gait patterns in sub-acute stroke patients based on open access gait kinematics
No full textNeurological disorders, such as stroke, can affect the ability to walk and balance. Robotic rehabilitation assists in training walking and balance capabilities of patients with neurological disorders. However, not all participants are good responders when using exoskeletons. This study aims to cluster gait patterns in stroke patients to provide insights into the pathology of stroke patients. Joint angles of the affected lower limb of 45 sub-acute stroke patients from an open access database were clustered based on a principal component analyses, followed by a k-means cluster analysis. A total of eight gait pattern clusters were retrieved and clinically rearranged into four categories. The results can be used in the field of robotic devices as well as a more clinical setting. Future research should focus on validating and using the retrieved clusters as clinical indicators for selecting suitable treatments, such as robotic devices or exoskeletons, to personalize rehabilitation
Steerable Anatomical Shape Synthesis with Implicit Neural Representations
No full textGenerative modeling of anatomical structures plays a crucial role in virtual imaging trials, which allow researchers to perform studies without the costs and constraints inherent to in vivo and phantom studies. For clinical relevance, generative models should allow targeted control to simulate specific patient populations rather than relying on purely random sampling. In this work, we propose a steerable generative model based on implicit neural representations. Implicit neural representations naturally support topology changes, making them well-suited for anatomical structures with varying topology, such as the thyroid. Our model learns a disentangled latent representation, enabling fine-grained control over shape variations. Evaluation includes reconstruction accuracy and anatomical plausibility. Our results demonstrate that the proposed model achieves high-quality shape generation while enabling targeted anatomical modifications.</p
On-Chip Stimulated Brillouin Scattering from Higher-Order Surface Acoustic Waves
No full textWe experimentally demonstrate stimulated Brillouin scattering from surface acoustic waves (SAWs) in GeAsSe waveguides on a chip. Our modeling shows that two different SAWs are involved in the scattering process, a fundamental and higher-order SAW.</p
Click-Click-Add – Product Search Strategies in Online Shopping
No full textPeople shopping online often abandon their shopping sessions because they feel overwhelmed or insufficiently supported during product searches. We instructed 31 participants to perform two goal-directed product searches online, simulating real-world scenarios for two product types: search products (laptops) and experience products (jackets). Through observation and think-aloud protocols, we captured user behavior across browser tabs and online resources, enabling us to develop a novel annotation scheme for product search that captures resources used, views seen, and actions taken. Qualitative analysis of these annotated sessions revealed nine distinct product search strategies, which participants often combined and applied at different stages of their search sessions. For each strategy, we describe similarities and differences between search and experience products and identify common strategy combinations across product types. Finally, by mapping these findings to established information-seeking models, we offer insights that can inform the design of more effective and supportive e-commerce platforms.</p
Multicolor Wavefront Shaping
No full textWavefront shaping allows for controlling light propagation and optical processes in otherwise opaque media. Wavefront shaping was invented in 2007 at COPS [1, 2] and has since found many uses in e.g. nanophotonics, cryptography [3] and biomedical imaging. A new challenge in wavefront shaping is control of multiple incident wavelengths. Normally, when an opaque sample is illuminated with plane waves of different wavelengths, each wavelength forms its own random speckle pattern, as illustrated in figure 1a. The scattering process for different wavelengths becomes independent if the wavelengths differ by more than the correlation bandwidth [4]. This means that each wavelength must be shaped independently, as illustrated in figure 1b, leading to a massive increase in complexity
From Prototype to Clinical Practice:How to Validate Novel Instruments for Non-Invasive Erectile Dysfunction Diagnostics?
No full textErectile dysfunction (ED) diagnostics are in need of innovation, as traditional tools like the RigiScan face usability challenges and limited clinical adoption. Although several novel sensor systems have been proposed, none have undergone comprehensive clinical validation. This opinion article outlines a structured, three-phase validation framework comprising component validation, system feasibility testing, and clinical validation, aligned with European MDR requirements. Special attention is given to key aspects such as diagnostic accuracy, sleep-stage monitoring, and patient experience. By providing a clear validation pathway, this opinion article aims to support researchers in the development of reliable, patient-friendly, and regulatory-ready tools for non-invasive ED diagnosis.</p