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What we do and do not know about public inquiries : a narrative review
Get PDFPublic inquiries have become a common governmental response to high-profile organisational failures, disasters or flagrant abuses of professional standards. Inquiries are detailed investigations charged with establishing ‘the facts’, ‘learning lessons’ and making recommendations to prevent similar events recurring. Despite their increasing frequency and public importance, knowledge about inquiries is limited and fragmented across political science, management science, organisation studies, science and technology studies, criminology, law and health. We reviewed the literature to synthesise learning from across these fields and identify gaps in understanding. We discuss five key concerns – political management of risk; sensemaking; procedure; learning and change; and the evolution of inquiries – and the research questions we see as arising from them. We suggest that there is a need to move beyond what we can learn from inquiry reports and, instead, to explore how people experience inquiries, what they value about them, and what personal, human costs are involved for whom
Open Stopband Suppressed, Gain Flatness Enhanced, and Cross-Polarization Reduced Leaky-Wave Antenna Using High-Order Mode Substrate Integrated Cavity
Get PDFA novel high-order mode substrate integrated cavity leaky-wave antenna (LWA) with high gain, low cross-polarization, and continuous beam scanning is proposed. The proposed antenna element employs mirror-symmetric arc-shaped slots within a circular substrate integrated cavity (CSIC), fed by a grounded coplanar waveguide. Moreover, the high-order TM110 mode of CSIC is employed to form an equivalent two-element array, enhancing element directivity and beam scanning capability. Unlike conventional LWAs, the proposed LWA achieves wide scanning and gain flatness enhanced by utilizing element-level beam scanning. Additionally, the open stopband is suppressed through impedance tuning of the arc-shaped slots, without degrading polarization purity. Experimental results demonstrate that the proposed LWA achieves a beam scanning range of –78° to 28° within a frequency range of 6.7 to 13 GHz, with a maximum gain of 17.3 dBi at 11 GHz, a peak radiation efficiency of 91%, and a cross-polarization ratio exceeding 45 dB
Medial Malleolar Fracture Fixation with Stainless Steel, Titanium, Magnesium, and PLGA Screws : A Finite Element Analysis
No full textBackground: Implant material may influence interfragmentary mechanics in medial malleolar (MM) fracture fixation. This study aimed to compare stainless steel, titanium, magnesium, and PLGA screws under identical conditions using finite element analysis (FEA). Methods: A CT-based ankle model with a unilateral oblique MM fracture (θ = 60° to the medial tibial plafond) was fixed with two parallel M4 × 35 mm screws placed perpendicular to the fracture plane (inter-axial distance 13 mm). Contacts were defined as nonlinear frictional, and each screw was assigned a pretension force of 2.5 N. Static single-leg stance was simulated with physiologic tibia/fibula load sharing. Four scenarios differed only by screw material. Primary outputs were interfragmentary micromotion (maximum sliding and gap). Secondary measures included fracture interface contact/frictional stresses, screw/bone von Mises stress, global construct displacement, and average tibiotalar cartilage contact pressure. Results: Interfragmentary micromotion increased as screw stiffness decreased. Maximum sliding was 32.2–33.8 µm with stainless steel/titanium, 40.4 µm with magnesium, and 65.0 µm with PLGA; corresponding gaps were 31.2–32.0 µm with stainless steel and titanium, 31.2 µm with magnesium, and 54.1 µm with PLGA, respectively. Interface stresses followed the same pattern: contact pressure (3.18–3.24 MPa for stainless steel/titanium/magnesium vs. 4.29 MPa for PLGA); frictional stress (1.46–1.49 MPa vs. 1.98 MPa). Peak screw von Mises stress was highest in stainless steel (104.1 MPa), then titanium (73.4 MPa), magnesium (47.4 MPa), and PLGA (17.9 MPa). Global axial displacement (0.26–0.27 mm) and average tibiotalar cartilage contact pressure (0.73–0.75 MPa) were essentially unchanged across materials. All conditions remained below commonly cited thresholds for primary bone healing (gap < 100 µm); however, PLGA exhibited a reduced safety margin. Conclusions: Under identical geometry and loading conditions, titanium and stainless steel yielded the most favorable interfragmentary mechanics for oblique MM fixation; magnesium showed intermediate performane, and PLGA produced substantially greater micromotion and interface stresses. These findings support the use of metallic screws when maximal initial stability is required and suggest that magnesium may be a selective alternative when reducing secondary implant removal is prioritized
CoGA : A Collaborative Gray-Box Adversarial Attack for Multimodal Language Models
Get PDFMultimodal language models (LMs) have shown significant potential for applications across various domains but remain vulnerable to adversarial attacks. Current research in white-box or black-box settings generally struggles with unrealistic attack assumptions and limited efficacy of targeted attacks. This paper introduces CoGA, a novel gray-box collaborative adversarial attack method for multimodal LMs. Under our gray-box settings, attackers have access only to the victim model’s input encoders. With the guidance of different modalities, we perturb the embedding representations from encoders to disrupt the semantic alignment across modalities, ultimately causing inaccurate outputs on various downstream tasks. Specifically, we integrate text embeddings into the loss calculations of the image attack and utilize image embeddings to guide the ranking of vulnerable words and the selection of final samples. Extensive experiments demonstrate that our method achieves superior attack performance across diverse models and tasks, suggesting the shared vulnerability of multimodal LMs in confronting adversarial challenges. Our work provides new insights into the security of multimodal LMs, facilitating the deployment of more robust and secure models in practical applications
Development of Superfluid Helium-3 Bolometry Using Nanowire Resonators with SQUID Readout for the QUEST-DMC Experiment
Get PDFSuperfluid helium-3 bolometers can be utilised for dark matter direct detection searches. The extremely low heat capacity of the B phase of the superfluid helium-3 at ultra-low temperatures offers the potential to reach world leading sensitivity to spin-dependent interactions of dark matter in the sub-GeV/c2 mass range. Here, we describe the development of bolometry using both micron scale and sub-micron diameter vibrating wire resonators, with a SQUID amplifier-based readout scheme. Characterisation of the resonators and bolometer measurements are shown, including the use of nonlinear operation and the corresponding corrections. The bolometer contains two vibrating wire resonators, enabling heat injection calibration and simultaneous bolometer tracking measurements. Coincident events measured on both vibrating wire resonators verify their response. We also demonstrate proof of concept frequency multiplexed readout. Development of these measurement techniques lays the foundations for the use of superfluid helium-3 bolometers, instrumented with vibrating nanomechanical resonators, for future low-threshold dark matter searches
Assessing the temporal clustering of coastal storm tide hazards under natural variability in a near 500-year model run
Get PDFThe temporal clustering of storms can present successive natural hazards for coastal areas in the form of extreme sea levels, storm surges and waves. Studies have investigated the prevalence of the temporal clustering of such hazards but are hindered by the rarity of the phenomena combined with short records and a lack of data availability around the coastline. This has made it difficult to determine if the levels of clustering reported were typical for the location or were being masked by natural variability or climate change over different timescales. In this study, we assess a near 500-year model simulation of extreme sea levels and storm surges forced with pre-industrial meteorological conditions to quantify the levels of temporal clustering seen from natural variability around Great Britain. We then utilise a 50-year rolling window to see how clustering statistics can change through time when dealing with time periods that are representative of the average length of a record in the United Kingdom National Tide Gauge Network. When using near 500-year timeseries, we highlight that many clustering statistics return values close to their statistical expectancies. However, when analysing discrete 50-year windows, results can vary dramatically. The percentage of years with an extreme sea level or surge exceedance at a given location at the 1 in 1-, 5-, and 10-year return level, can vary by up to ~ 33%, ~ 24%, and ~ 18%, the mean number of days between consecutive sea level or surge exceedances can vary by ~ 231, ~14,780, and ~ 17,793 days, and the extremal index can vary by ~ 0.37, ~ 0.64, and ~ 0.79, respectively. Although these results represent the best estimate of the levels of clustering to be expected under natural variability, a comparison of the longest records in the tide gauge network and their nearest model grid nodes shows a tendency for the model to underestimate the clustering statistics that are calculated from the measured data (apart from the extremal index). As such, these can be considered to represent the minimum levels of temporal clustering around Great Britain, as the potential underestimation of clustering, combined with climatic change and sea level rise, means that the temporal clustering of sea levels and storm surges are likely to be far greater over the next 500 years
Hospital Manager Panels under the Mental Health Act 1983
Get PDFSecure mental healthcare works through the interaction between the patient, healthcare professionals, Hospital Managers, the Mental Health Tribunal and the patient’s family. These people all have a role in determining whether a person’s detention or Community Treatment Order (CTO) should continue. Associate Hospital Managers (AHMs) are members of the local community who sit on Hospital Manager Panels (HMPs). HMPs have the power to discharge people from detention or CTOs under section 23 of the Mental Health Act (MHA) 1983 against medical advice. This research looks at the lack of evidence about how AHMs, and the panels, operate, what their role should be, and why the role of AHM’s is important
Global nutritional equity of fishmeal and aquaculture trade flows
Get PDFAquaculture, the single fastest growing food sector, is central to achieving key Sustainable Development Goals (e.g., SDG 2: Zero Hunger). Linking the nutrient composition of >2,800 aquatic species with >2 million fishmeal and farmed fish transactions in international aquatic food trade between 2015 and 2019, we examined aquaculture's nutritional flows and distributional equity. We found that aquaculture provided adequate intakes for nearly a quarter of a million individuals, on average, across 14 key nutrients, and for up to 2.7 billion individuals for several nutrients, such as Vitamin B . The vast majority of these nutrients (76.8%) were domestically retained, contributing to the nutritional security of producer countries. With most internationally traded nutrients originating from nutritionally vulnerable countries (57.7% for fishmeal and 66.3% for farmed aquatic foods), rethinking existing distribution policies with nutrition as the primary objective may help unlock the full potential of aquaculture to eliminate hunger and malnutrition