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Lignin enabling facile 3D printing of rubber for all‐weather water harvesting
Get PDFSoft materials, with high elasticity and low glass transition temperatures (Tgs), present significant challenges in fabricating finely structured components via 3D printing due to their inherent softness and slow curing kinetics. Current direct ink writing (DIW) methods for soft polymers typically rely on external stimuli (e.g., light and heat) or precious metal catalysts to ensure structural stability during printing, increasing process complexity and cost. Here, a simple DIW 3D printing strategy for rubber was developed by introducing modified lignin. By virtue of its rigid benzene ring structure and abundant reactive groups, the modified lignin forms covalently bonded crosslinked networks and intermolecular hydrogen bonds with rubber to enhance the viscoelasticity, and thixotropy of the ink. The addition of 30–50 wt% modified lignin increased the modulus of the ink by five orders of magnitude, which resulted in stable self-supported printing during the printing process. Water-collecting materials with a bionic cactus spine structure were fabricated utilizing 3D printing, which demonstrated superior capabilities for efficient fog capturing and photothermal evaporation, respectively. By combining these two water-harvesting methods, a daily cycle can ideally deliver an overall water yield approximately 22 L m−2, which will providing a high-performance solution for all-weather fresh water access
Business model innovation in the context of crisis : a qualitative longitudinal analysis
No full textThe Covid-19 pandemic highlighted the challenges firms face in engaging in Business Model Innovation (BMI) during a crisis. To better understand how and why entrepreneurial firms undertake BMI during periods of uncertainty this study employs a novel methodology to systematically identify how firms shift their business model by using qualitative longitudinal data based on 229 interviews with 85 high-growth British entrepreneurs. The findings suggest three core archetypes of BMI in crisis: Crisis Response, Crisis Enablement, and Planned Innovation. Each archetype is underpinned by specific drivers and processes that explain why and how BMI occurred
Martian aqua : occurrence of water and appraisal of acquisition technologies
No full textThe production of water through in-situ resource utilization (ISRU) will be necessary for a sustainable human presence on Mars. Accessible water on Mars occurs as ice (pure and mixed with regolith), bounded water in the regolith (adsorbed and in hydrated minerals) and vapor in the atmosphere. Harvesting water from the atmosphere appears to be relatively challenging than obtaining it from the regolith. However, the potential landing sites for human exploration are unlikely to have easy access to near-surface ice of any form, while utilization of the atmosphere can be accomplished almost anywhere. Extensive research has been conducted on atmospheric water vapor, which is ubiquitous and renewable, yet provides only a thin water source across the planet. This paper provides an overview of water availability on Mars, investigates the volatiles (CO2, H2O) phase equilibria in the atmosphere-surface system of the planet, and compares water harvesting from the atmosphere to obtaining water from the regolith. The findings indicate that while atmospheric water harvesting does not appear to be feasible to serve as the primary water source, it might have potential to become a supplementary, decentralized clean water supply. Atmospheric water harvesting systems on Mars require more power and energy, but they offer greater simplicity and flexibility compared to water extraction from the regolith. This approach could prove valuable in regions where water extraction from the regolith is infeasible or as a temporary backup in the event of a primary water system failure. Such a distributed water harvesting method might enhance the resilience and flexibility of water supply systems for future human Mars missions and settlements. Ultimately, any technology developed for extraterrestrial environments can have important applications on Earth
Observation of quantum effects on radiation reaction in strong fields
No full textRadiation reaction, the force experienced by an accelerated charge due to radiation emission, has long been the subject of extensive theoretical and experimental research. Experimental verification of a quantum, strong-field description of radiation reaction is fundamentally important, and has wide-ranging implications for astrophysics, laser-driven particle acceleration, next-generation particle colliders and inverse-Compton photon sources for medical and industrial applications. However, the difficulty of accessing regimes where strong field and quantum effects dominate inhibited previous efforts to observe quantum radiation reaction in charged particle dynamics with high significance. We report a high significance ( > 5σ) observation of strong-field radiation reaction on electron spectra where quantum effects are substantial. We obtain quantitative, strong evidence favouring the quantum-continuous and quantum-stochastic models over the classical model; the quantum models perform comparably. The lower electron energy losses predicted by the quantum models account for their improved performance. Model comparison was performed using a novel Bayesian framework, which has widespread utility for laser-particle collision experiments, including those utilising conventional accelerators, where some collision parameters cannot be measured directly
A novel fractional-order derivative-based method for frequency estimation in low-inertia future grids
Get PDFThis article proposes a novel frequency estimation method based on fractional-order derivatives, designed to meet the rapid response requirements of modern low-inertia power systems. The proposed method utilizes the Park-Clark transformation to convert three-phase system voltages into \boldsymbol{d}\boldsymbol{q} components, which oscillate at a frequency deviation corresponding to the difference between the actual system frequency and a predefined reference frequency. A new analytical formulation is derived using fractional-order derivatives to process these oscillatory components and estimate the frequency deviation. The actual system frequency is then obtained by summing this deviation with the reference value. In contrast to conventional phase-locked loop (PLL) methods, which rely on integral control and are inherently limited by dynamic delays, the proposed method eliminates such latency. The performance of the proposed method is thoroughly evaluated through rigorous mathematical analysis, which encompasses its resilience to both noise and harmonic distortion, as well as its stability in the presence of measurement inaccuracies. Experimental validation is carried out using a real-time hardware-in-the-loop (HIL) setup, incorporating a CINERGIA programmable grid emulator. The proposed method is benchmarked against recent advanced PLL-based methods across a diverse set of grid disturbance scenarios. Results confirm that the proposed method achieves superior estimation accuracy, reduced response time, and enhanced robustness compared with the existing methods
Aircraft wake vortex encounters with residential structures
No full textPresented in the following work is a comprehensive analysis of wake vortex encounters with residential structures. From the results of high fidelity LES simulations, the dynamics and underlying flow structures which govern these potentially damaging encounters have been identified. Through evaluation of the pressure loads transmitted to the roof surface, the potential for damage to occur to a residential structure as a result of wake vortex exposure has been evaluated for a variety of cases. Regarding the building’s design, structures possessing larger pitch angles and thus steeper roofs have been found to sustain the largest peak loads for their encounter with an identical wake vortex system as compared to their flatter roofed counterparts. Similarly, upon assessing the effect of the environmental conditions it was observed that for increasingly turbulent atmospheres, the wake vortex encounter would occur sooner and with a reduced intensity compared to more neutral conditions. These behaviours have been attributed to the effects of secondary flow structures formed from the shedding of vorticity from the building surface or from wake vortex interactions with the eddies that comprise the atmospheric environment. These secondary flow structures energise wake vortex instability mechanisms thus leading to the variations in pressure loads sustained by the roof. With respect to the impact orientation, we note that there exists a minimal difference on the pressure loads generated during a wake vortex encounter for small angular offsets up to 20°
Ultrasonic phased array measurement & compression for in-process weld bevel estimation
Get PDFThis work presents a real-time ultrasonic inspection pipeline for weld bevel orientation measurement in robotic welding applications, addressing two major barriers to industrial deployment: reliable bevel geometry estimation in challenging environments and efficient management of high-throughput ultrasonic data. While phased array ultrasonics provides volumetric imaging where optical methods fail, its application in robotics has been limited by data scale and latency. Validated across both conventional V-groove and 120 mm thick narrow-gap geometries, the integrated GPU-accelerated orientation estimator and lightweight AUC compression strategy deliver ±0.4° angular precision for conventional V-grooves; the pipeline achieves sub-250 ms execution for single-probe V-groove scanning and sub-1500 ms for complex dual-tandem narrow-gap configurations, maintaining over 88% data reduction with geometric errors below 3 mm. The system is validated on a robotically deployed phased array platform dynamically scanning stepped bevel geometries, simulating realistic industrial scenarios. Rather than focusing on novel algorithms in isolation, the contribution lies in demonstrating, for the first time, a modular and interpretable FMC pipeline that achieves real-time weld geometry inference in tandem with data sparsification. This proof-of-concept highlights a viable pathway toward embedded, closed-loop ultrasonic inspection for robotic welding automation
Colour of medicines and children’s acceptability : What children think of the colour of oral dosage forms?
Get PDFBackground Colour plays an important role in shaping consumer experiences, and in the context of medicines, it may influence patients’ expectations, behaviours, and treatment adherence. There is limited research on how children respond to medicine colour, despite their increased sensitivity to sensory cues. A previous literature review indicated that colour may affect medicine acceptability in children but highlighted the need for further research. This cross-sectional study aimed to fill that gap by directly collecting children’s opinions on the colour of oral medicines through an online survey, targeting a diverse paediatric population across age, health status, and countries in Europe. Methods The survey, developed by UCL School of Pharmacy UCL REC (ID 26765/001) and reviewed by experts of the European Young Persons Advisory Group Network (eYPAGnet), was translated into five languages and distributed via QR codes and anonymous links. Response collection occurred between September 2024 and April 2025. Participants included children aged 3 to 18, with parental assistance when needed and parental consent. Responses were analysed using the software R Studio. Results Out of 669 people who accessed the survey, 382 completed it. For liquids, pink (23%), colourless (16.5%), and blue (15.2%) were most preferred. Reasons included appealing look and taste associations (e.g., strawberry for pink). For solids, white (29.1%), pink (18%), and blue (12.5%) led, with neutral appearance and berry-related flavours cited. Statistically significant gender and age differences in preferences emerged, while variations by health, or country were not always significant. Ratings for previously used medicines highlighted preference for purple, pink, and blue, while white and colourless received moderate scores. A statistically significant link between taste and colour emerged (ρ = 0.42, p- value 2.2 × 10 −16 ), suggesting that the colour of a medicine may influence children’s anticipation of its taste and shape their overall expectations of the treatment experience. Conclusion This study offers valuable insight into children’s preferences for medicine colour. Pink and blue were associated with sweet/flavourful tastes, while neutral colours were perceived as tasteless, particularly by participants aged 12–18 years. These findings can inform paediatric formulation strategies, particularly the selection and use of colouring agents, in alignment with current regulatory requirements when their inclusion is considered necessary
Talking to, talking back : sex/gender as a dialogic process
Get PDFDebates have grown regarding the meaning and usage of the terms ‘sex’ and ‘gender’ in the UK. There is an influential ‘gender-critical’ movement that views sex as immutable biological reality, and advocates for this understanding to guide policymaking and politics. In contrast, this article argues that theories of sex and gender should account for both biological and sociocultural aspects, as well as interactions between the subject and the social world. To highlight interactions between biology, society and culture, this article takes sex/gender as one concept. It outlines how sex/gender can be viewed as a dialogic process of constant engagement with, and response to, the other. It centres Bakhtin’s concept of the ‘dialogic’, which denotes the continuous unfinished dialogue with others that moulds all language and cognition. The article first explores how some feminist theorists have addressed these questions. It builds especially on Butler, Moi and Young’s works, particularly the notion that gender can be viewed not as a set of shared features but a personal experiential response. Likewise, this article argues that subjects are born into prevailing sex/gender structures, shaped by societal norms and expectations, and can only respond to these. However, each response also generates the potential for change. In illustrating these points, the article explores one type of response, ‘embodied texts’, which construct narratives from lived experience. Focusing on trans writing, these texts can create space for trans writers to resist erasure and challenge mainstream discourses. As an effective example of such resistance, the article analyses Harry Josephine Giles’s transfeminist zine, Wages for Transition (2019)
Design and parameters optimization of an ultrasonic gas flow meter using simulation-assisted full factorial methodology
Get PDFUltrasonic transducers are widely used in gas flow metering due to their high accuracy and absence of moving parts. However, designing high-performance transducers often requires extensive prototyping and time-consuming trial-and-error. This study presents a simulation-driven design approach that combines a full factorial Design of Experiments (DOE) with finite element analysis to streamline and optimise transducer development. A total of 208 transducer configurations were simulated using finite element software (OnScale), varying three key parameters: matching layer material, matching layer thickness, and the presence of a light backing layer. The active element was an 8 mm diameter, 1 mm thick PIC255 piezoelectric disc operating in radial mode at 238 kHz. The design objectives were to maximise acoustic pressure while minimising pulse duration, both of which are critical for gas flow measurement resolution. The optimal configuration identified was 1 mm grey matching layer (ρ = 681.6 kg/m³) combined with a 5 mm RTV 664 backing layer. Multivariate analysis showed that matching layer thickness was the most influential parameter for both amplitude (58.49%) and pulse duration (59.44%). Its interaction with material type and backing configuration also had a significant impact on performance. Experimental validation confirmed the simulation trends, yielding a measured peak voltage of 5.87 × 10⁻⁴ V and a pulse duration of 2.61 × 10⁻⁴ s, compared to simulated values of 6.54 × 10⁻⁴ V and 3.31 × 10⁻⁴ s. this corresponds to errors of 10.24% in amplitude and 26.82% in pulse duration. Overall, the proposed approach reduces reliance on physical prototyping while providing reliable performance prediction, offering a practical and scalable method for ultrasonic transducer optimisation in gas sensing applications
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