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MapEx: Indoor Structure Exploration with Probabilistic Information Gain from Global Map Predictions
No full textExploration is a critical challenge in robotics centered on understanding unknown environments In this work we focus on structured indoor environments which often exhibit predictable repeating patterns Conventional frontier based exploration approaches have difficulty leveraging this predictability relying on simple heuristics such as closest first for exploration More recent deep learning based methods predict unknown regions of the map for information gain computation but these approaches are often sensitive to the predicted map quality or fail to account for sensor coverage To overcome these issues our key insight is to jointly reason over what the robot can observe and its uncertainty to calculate probabilistic information gain We introduce MapEx a new exploration framework that uses predicted maps to form probabilistic sensor model for information gain estimation MapEx generates multiple predicted maps based on observed information and takes into consideration both the computed variances of predicted maps and estimated visible area to estimate the information gain of a given viewpoint Experiments on the real world KTH dataset showed on average 12 4 improvement than representative map prediction based exploration and 25 4 improvement than nearest frontier approach Website https mapex explorer github i
AuditableLLM: A Hash-Chain-Backed, Compliance-Aware Auditable Framework for Large Language Models
Get PDFAuditability and regulatory compliance are increasingly required for deploying large language models (LLMs). Prior work typically targets isolated stages such as training or unlearning and lacks a unified mechanism for verifiable accountability across model updates. This paper presents AuditableLLM, a lightweight framework that decouples update execution from an audit-and-verification layer and records each update as a hash-chain-backed, tamper-evident audit trail. The framework supports parameter-efficient fine-tuning such as Low-Rank Adaptation (LoRA) and Quantized LoRA (QLoRA), full-parameter optimization, continual learning, and data unlearning, enabling third-party verification without access to model internals or raw logs. Experiments on LLaMA-family models with LoRA adapters and the MovieLens dataset show negligible utility degradation (below 0.2% in accuracy and macro-F1) with modest overhead (3.4 ms/step; 5.7% slowdown) and sub-second audit validation in the evaluated setting. Under a simple loss-based membership inference attack on the forget set, the audit layer does not increase membership leakage relative to the underlying unlearning algorithm. Overall, the results indicate that hash-chain-backed audit logging can be integrated into practical LLM adaptation, update, and unlearning workflows with low overhead and verifiable integrity
Youth advisory boards: a scoping review of characteristics, youth engagement activities and role in inclusive research
Get PDFCarers' Perceptions of Seclusion and Restraints in Mental Healthcare: An Integrative Literature Review.
No full textThe use of seclusion and restraints in mental health care is a significant international concern. Although these practices are perceived to de-escalate volatile situations and provide physical protection for those involved, they raise critical issues such as the violation of human rights, physical and emotional harm. Despite the crucial role of carers in recovery, care and protection for persons with lived experience of mental health conditions, few studies have explored their perspectives on seclusion and restraints. This integrative literature review explored carers' perceptions of these practices. A systematic search of four electronic databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, was conducted without time limitations, resulting in 10 final studies. The synthesis of the literature revealed that carers and persons with lived experience of mental health conditions have negative experiences of seclusion and restraints. However, while carers desire the elimination of seclusion and restraints, some do support the limited use, such as a 'last resort'. Importantly, many carers want to be involved before, during and after these events. Current evidence suggests that empathy is a key in de-escalation that is planned with persons with lived experience and their carers. Healthcare providers should prioritise carers' needs for engagement, emotional support and access to related information for effective reduction and elimination of seclusion and restraints. Training on de-escalation should focus on empathy, therapeutic relationships and communication during crisis. Empirical research should explore the role of carers in developing de-escalation plans
Genetic signatures of bufadienolide resistance are poor predictors of cane toad toxin resistance in crocodilians
No full textAs an invasive species in northern Australia, the cane toad (Rhinella marina) has caused the decline of many native predator populations that lack resistance to toad toxin. Freshwater crocodiles (Crocodylus johnstoni) are particularly affected due to ingestion of cane toads, whereas saltwater crocodiles (Crocodylus porosus) appear to be resistant. We hypothesised that this difference in resistance may be due to sequence differences in the extracellular H1-H2 domain of the alpha subunit of the Na/K ATPase transmembrane pump, which have previously been shown to correlate with susceptibility to bufadienolides – a major component of toad toxin. Unexpectedly, predicted H1-H2 domain sequences were identical between C. johnstoni and C. porosus in all three of the candidate paralogous genes (ATP1A1, ATP1A2 and ATP1A3) implicated in bufadienolide resistance. Moreover, sequence motifs in ATP1A1 and ATP1A3 were predictive of bufadienolide resistance, suggesting that other mechanisms drive cane toad toxin susceptibility in C. johnstoni. We discuss alternative possible explanations for our observations based on crocodilian evolution, physiology, and other active components of toad toxin
Supine hyperinflation and expiratory flow limitation are associated with respiratory arousals and nocturnal hypoventilation in COPD.
Get PDFINTRODUCTION: Subjective sleep disturbance is common in chronic obstructive pulmonary disease (COPD) and is related to hyperinflation when supine and tidal expiratory flow limitation (EFL). We hypothesised that abnormalities in supine lung mechanics disturb sleep and impair gas exchange in COPD. We aimed to assess relationships between supine lung derecruitment, EFL and hyperinflation, and polysomnographic measures of sleep disturbance and gas exchange in COPD. METHODS: In this prospective, observational study, supine oscillometry was performed in stable COPD patients to assess lung derecruitment (reactance at 5 Hz (Xrs5) z-score) and EFL (difference between mean inspiratory and expiratory reactance (∆Xrs5)). Hyperinflation was assessed by supine inspiratory capacity (ICsupine) z-score. In-laboratory polysomnography was used to assess sleep disturbance, measured by Apnoea-Hypopnoea Index (AHI), Oxygen Desaturation Index (ODI) and AHI during rapid eye movement sleep (AHI REM). Monitoring of transcutaneous carbon dioxide (TcCO2), and measurements of partial pressure of arterial carbon dioxide (PaCO2) and HCO3 - were performed in a subgroup. RESULTS: 28 COPD patients were enrolled (13 female, mean age (SD) 67.5 (8.71) years and mean forced expiratory volume in 1second (FEV1) z-scores (SD) -2.61 (1.06)). Worse Xrs5(supine) correlated with greater respiratory arousals (AHI rs =0.47, p=0.01; ODI rs=-0.58, p=0.001), as did greater ∆Xrs5(supine) (AHI REM rs=0.53, p=0.005). Xrs5(supine) correlated with peripheral oxygen saturation nadir (rs=0.43, p=0.02). ICsupine correlated negatively with hypoventilation (PaCO2 rs=-0.77, p=0.001; HCO3 - rs=-0.78, p=0.001, n=15), as did Xrs5(supine) (rise in TcCO2 rs=-0.65, p=0.009). CONCLUSION: Lung derecruitment, EFL and supine hyperinflation likely contribute to sleep disturbance and sleep-related gas exchange impairment in COPD
A novel transformer-based approach for predicting frost heave of high-speed railway in cold regions
No full textIn cold regions, the frost-heave of soil can cause uneven railway subgrades, affecting the safety and efficiency of high-speed railways. This study proposes a novel PCW-iTransformer model for predicting frost heave, which integrates PCHIP data interpolation, CEEMDAN signal decomposition, and WPT denoising to extract sequential features. Compared to existing models like Autoformer, Crossformer, and DLinear, PCW-iTransformer achieves a reduction of 19.1%–34.5% in error metrics and an improvement of 2.8%–4.6% in the coefficient of determination. Additionally, a fused parameter model based on normalized moisture and temperature improves prediction accuracy, reducing MSE, MAE, and RMSE by up to 7.6%. The model also demonstrates robustness under data scarcity, maintaining stable performance with 40% continuous or 60% random missing data. Overall, PCW-iTransformer provides a reliable approach for predicting frost heave, offering valuable insights for the maintaining and long-term stability of high-speed railway subgrades in cold regions
Mechanical performance of FDM-printed PLA TPMS lattices under hydrothermal aging
No full textTriply periodic minimal surface (TPMS) metamaterials exhibit superior mechanical properties, yet their response to hydrothermal aging remains largely unexplored. This study explores the hydrothermal aging behavior of TPMS lattice metamaterials with four distinct architectures, i.e., Primitive (P), Gyroid (G), Diamond (D) and I-Wrapped Primitive (IWP). The metamaterials were additively manufactured using fused deposition modeling (FDM) with polylactide (PLA) and subjected to water immersion at 50 °C for up to 30 days. Compression tests showed that all the metamaterials lost load carrying capacity after 30 days of aging due to material degradation. The G and D lattices exhibited the highest retention of mechanical properties, maintaining 96% and 94% of their initial peak stresses after 18 days. This superior performance is attributed to more cycles of variation in their load-bearing areas. In contrast, the P lattice, with fewer variation cycles, exhibited the weakest mechanical properties and the largest increase in stress fluctuation. Notably, the IWP lattice was most sensitive to aging, with mechanical degradation beginning on day 7. Moreover, TPMS lattice metamaterials loaded perpendicular to the building direction (⊥BD) degraded more rapidly than those loaded along the building direction (∥BD). This was evident at the material level, where the interlayer bonding had half the tensile strength of the filaments and deteriorated significantly during aging, confirming interlayer debonding as the dominated failure mode. These findings highlight the importance of architecture and interlayer bonding in the aging behavior of 3D printed metamaterials
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