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Algorithmic Tenancies and the Ordinal Tenant:Digital Risk-profiling in England’s Private Rented Sector
No full textCharacterisation of an oat protein-beta-glucan co-extract
No full textWe characterise a novel, dilute protein concentrate produced via alkaline extraction of defatted oat flour (DOF) without additional protein purification and identify a self-assembly of oat protein and dietary fibre (primarily oat β-glucan). The oat protein-β-glucan co-extract (OPBG) was characterised using sodium dodecyl-sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and showed multiple protein bands, with major bands assigned to oat 12S globulin monomers (65-67 kDa) and its subunits (45 and 22 kDa). Circular dichroism (CD) spectroscopy revealed high quantities of β-sheet and random coil structures with evidence of partial protein unfolding at pH 2.0. The co-extract showed various degrees of aggregation when subjected to different pH (pH 2.0-10.0) and ionic strength (0-1.0 M added NaCl) conditions. At pH 2.0, β-glucan-β-glucan aggregates appeared dispersed in a continuous protein phase. At pH 7.0, OPBG displayed a compact aggregated microstructure with a hydrodynamic diameter (dH) of ∼100-150 nm and a polydispersity index of 0.28, where binary protein-β-glucan clusters co-existed with singular entities, i.e. protein-protein and β-glucan-β-glucan aggregates. Complementary ζ-potential measurements confirmed a negative surface charge at pH 7.0 and isoelectric point (pI) of 4.0-4.5. As the pH increased to 10.0, confocal laser scanning microscopy (CLSM) images revealed strong colocalisation of the protein and β-glucan, with consequent evolution of a smaller peak (dH ∼ 20 nm) resembling oat 12S globulin hexamers. Overall, hydrogen bonding appeared to dominate the protein-polysaccharide interactions in OPBG, whilst its colloidal properties, including responsiveness to pH and added salt, seemed to be largely governed by the proteinaceous fraction
Mirosław Michał Sadowski, Intersections of Law and Memory: Influencing Perceptions of the Past, Abingdon, Oxon and New York, Routledge, 2024, 304 pp, hb, £135.00
No full textBook review of Intersections of Law and Memory: Influencing Perceptions of the Past by Mirosław Michał Sadowsk
Digital Dong: Heritage assessment, reality capturing and 3D modelling
No full textThis original paper presents the digital documentation and reconstruction of the endangered drum tower building and its contemporary surroundings in Dong villages of peripheral mountains of southwestern China. The research methods adopted a series of digital techniques, including 3D terrestrial LiDAR scanning, aerial and close-range photography and photogrammetry, alongside conventional humanities methods such as ethnographic observation and oral histories with local carpenters and communities. Much as an unknown construction heritage from outside Dong and a heavily used everyday space inside Dong, the drum tower has met severe threats from human and wild fires, natural decay due to material degradation and climate change, as well as urbanisation and modern tourism. Hence a timely and thoroughly digital assessment, analysis, and documentation of the historic structures is a necessity, which will serve as an evidence base for subsequent conservation, maintenance and repair interventions. The paper will present latest case studies highlighting the above workflow from on-site assessment to surveying, reality capturing and 3D digital modelling. This paper is part of the results from the EWAP Large Grant ‘Decoding Dong: Documentation of Dong Minority Villages’ Drum Tower and Wooden Heritage’, funded by Arcadia (EWAP2039LG, 2023-2025)
Combining sequential test cases into an equivalent set of adaptive test cases
No full textWhen testing a state-based system one might use a set of (negative) test cases in which each test case is a sequence of events that should not occur. Testing then involves executing the system under test (SUT) in order to check whether any of these disallowed sequences can occur. While testing using such sequences can be effective, they introduce a source of inefficiency: if a test case expects the SUT to produce output a after observing a sequence σ and the SUT instead produces a different output a' after σ then testing with that test case did not show an error, because the SUT can autonomously produce outputs, and terminates because the test case only makes sense if the exact sequence is observed. This is a source of inefficiency if there is another test case that starts with σ followed by a': we could have continued evaluating whether the application of this second test case leads to an error. This paper considers scenarios in which events represent inputs, outputs, or the passing of discrete time. We show how a set of sequential test cases can be converted into an equivalent set of adaptive test cases, with adaptivity addressing the above source of inefficiency. The proposed approach has the potential to improve efficiency when using any test generation technique that returns negative sequential test cases
Moderate rating bias in interpersonal recommendations
No full textTourists often convey ratings in interpersonal recommendations to close others. However, extant research offers limited insight into whether such recommendations are received as intended. This research uncovers a “Moderate Rating Bias,” where tourists systematically overestimate close others’ likelihood of accepting their moderately rated recommendations (e.g., 3 out of 5). We show that this bias stems from asymmetric evaluations of such recommendations: recommenders focus on shared preferences, interpreting moderate ratings through a social lens, while recipients emphasize their unique preferences, viewing them more objectively. This bias diminishes when ratings clearly indicate positive (e.g., 5 out of 5) or negative (e.g., 1 out of 5) experiential quality or when moderate ratings reflect divergent performance across experiential dimensions (e.g., “excellent food, poor service”). We present evidence from five experiments (four preregistered and one with an incentive-compatible design) to support our theorizing. These findings provide novel insights into how tourists interpret peer recommendations and offer guidance for managing tourism experiences
Adhesive layer formation and its dual role in tribological performance and surface integrity of Ti-6Al-4V: implications for the machining process
No full textThe poor machinability of Ti-6Al-4V (Ti64), characterized by adhesive and abrasive wear, low thermal conductivity, and high chemical reactivity, continues to hinder efficient manufacturing. Among these challenges, adhesive layer formation on tool flank faces remains poorly understood despite its critical influence on tool degradation and workpiece surface integrity. To address this, this study investigates the tribological behaviour of WC/Co-Ti64 pin-on-disc sliding contacts under dry and minimum quantity lubrication (MQL) conditions through both experimental and numerical approaches. Experimental results show that thick, stable, and intact adhesive layers transferred from Ti64 discs was formed on WC/Co pin surfaces under dry and low MQL flowrate conditions. These layers are associated with reduced friction coefficients and lower disc wear but simultaneously contribute to compromised surface integrity. Comparative boundary element method (BEM) simulations with 316 L stainless steel reveal that the lower elastic modulus of Ti64 adhesive layers significantly reduces nominal contact pressure and subsurface von Mises stress, lowering friction coefficients and enhancing mechanical stability of adhesive layer. However, the accompanying increase in surface roughness intensifies local stress concentrations and result in thicker work-hardened layers on Ti64 disc, which align well with BEM simulation results. Conversely, high MQL flowrate inhibited adhesive layer formation, leading to higher friction and wear but producing smoother surfaces and thinner work-hardened layer. The findings offer new mechanistic insights into complex interplay between adhesive layer, lubrication and surface topography, and present the first direct evidence of the dual role of adhesive layer: reducing friction and tool-side wear but compromising workpiece surface integrity
Disaggregation of a tracer cloud in accelerating transitional pipe flow
No full textPrevious studies on longitudinal solute transport in a pipe during acceleration from laminar to turbulent flow highlighted a disaggregation of the tracer cloud resulting in two peaks occurring downstream from a single pulse injection. It was hypothesized that the disaggregation was caused by the spatially nonuniform acceleration of flow at different radial locations. This study improves the previous understanding of solute transport during accelerating flow using novel laboratory measurements of pipe cross-sectional tracer distribution from planar laser-induced fluorescence and radial velocity profiles from an ultrasonic velocity profiler. Disaggregation of the tracer cloud was observed, with the tracer not being uniformly distributed within the cross-section at the first peak but cross-sectionally well-mixed at the second peak. The relative magnitude of the first peak, compared with the second peak, decreased with the time of injection (and therefore with increased Reynolds number) after the start of the acceleration. Radial velocity profiles showed that the central core of the flow exhibited a smooth, linear increase in velocity compared with the flow closer to the pipe boundary. The data also revealed, for the first time to our knowledge, that the transition time to different flow regimes increased with distance downstream. A model based on the 2D advection-dispersion equation, parameterized using experimental data, was employed to describe the flow and mixing processes during the acceleration. In addition to the combined effects of the radial velocity profile and radial diffusion coefficient, this study confirms that it is essential to also include the delay in the transition time at downstream locations to create the observed disaggregation
Community challenge towards consensus on characterization of biological tissue: C4Bio’s first findings
No full textThis study investigates methodological variability across various expert laboratories worldwide, with regards to characterizing the mechanical properties of biological tissues. Two testing rounds were conducted on the specific use case of uniaxial tensile testing of porcine aorta. In the first round, 24 labs were invited to apply their established methods to assess inter-laboratory variability. This revealed significant methodological diversity and associated variability in the stress–stretch results, underscoring the necessity for a standardized approach.
In the second round, a consensus protocol was collaboratively developed and adopted by 19 labs in an attempt to minimize variability. This involved standardized sample preparation and uniformity in testing protocol, including the use of a common cutting and thickness measurement tool. Despite protocol harmonization, significant variability persisted across labs, which could not be solely attributed to inherent biological differences in tissue samples.
These results illustrate the challenges in unifying testing methods across different research settings, underlining the necessity for further refinement of testing practices. Enhancing consistency in biomechanical experiments is pivotal when comparing results across studies, as well as when using the resulting material properties for in silico simulations in medical research