Publications by authors named "David Logan"

This article reviews recent progress in understanding the physics of many-body localisation (MBL) in disordered and interacting quantum many-body systems, from the perspective of ergodicity breaking on the associated Fock space. This approach to MBL is underpinned by mapping the dynamics of the many-body system onto that of a fictitious single particle on the high-dimensional, correlated and disordered Fock-space graph; yet, as we elaborate, the problem is fundamentally different from that of conventional Anderson localisation on high-dimensional or hierarchical graphs. We discuss in detail the nature of eigenstate correlations on the Fock space, both static and dynamic, and in the ergodic and many-body localised phases as well as in the vicinity of the MBL transition.

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During touch, mechanical forces are converted into electrochemical signals by tactile organs made of neurons, accessory cells, and their shared extracellular spaces. Accessory cells, including Merkel cells, keratinocytes, lamellar cells, and glia, play an important role in the sensation of touch. In some cases, these cells are intrinsically mechanosensitive; however, other roles include the release of chemical messengers, the chemical modification of spaces that are shared with neurons, and the tuning of neural sensitivity by direct physical contact.

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Animosity between drivers and cyclists has existed on urban road networks for many years. Conflicts between these two groups of road users are exceptionally high in the shared right-of-way environments. Benchmarking methods of conflict assessments are mostly based on statistical analysis with limited data sources.

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In image-based profiling, software extracts thousands of morphological features of cells from multi-channel fluorescence microscopy images, yielding single-cell profiles that can be used for basic research and drug discovery. Powerful applications have been proven, including clustering chemical and genetic perturbations on the basis of their similar morphological impact, identifying disease phenotypes by observing differences in profiles between healthy and diseased cells and predicting assay outcomes by using machine learning, among many others. Here, we provide an updated protocol for the most popular assay for image-based profiling, Cell Painting.

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Background: Previous research showed differences in the exposure to risk from using different modes of transport and that modal choice can significantly impact road safety outcomes. Though, a modal shift to a safer mode is not commonly discussed as part of road safety strategies.

Aim: This study aimed to explore the perspectives of transport policymakers about the role of safety in modal choice and if it can be one of the main factors for modal choice and shift.

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Energy flow in molecules, like the dynamics of other many-dimensional finite systems, involves quantum transport across a dense network of near-resonant states. For molecules in their electronic ground state, the network is ordinarily provided by anharmonic vibrational Fermi resonances. Surface crossing between different electronic states provides another route to chaotic motion and energy redistribution.

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Morphological and gene expression profiling can cost-effectively capture thousands of features in thousands of samples across perturbations by disease, mutation, or drug treatments, but it is unclear to what extent the two modalities capture overlapping versus complementary information. Here, using both the L1000 and Cell Painting assays to profile gene expression and cell morphology, respectively, we perturb human A549 lung cancer cells with 1,327 small molecules from the Drug Repurposing Hub across six doses, providing a data resource including dose-response data from both assays. The two assays capture both shared and complementary information for mapping cell state.

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Objective: To investigate the impact of a road safety programme on adolescents' willingness to engage in risky behaviour as probationary drivers, adjusted for covariates of interest.

Method: The streetsmart is a road safety programme delivered to around 25 000 adolescent students annually in New South Wales. Using a smartphone-based app, student and teacher participation incentives, students were surveyed before and after programme attendance.

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The overall objective of the current study was to investigate the behaviours and knowledge of parents/carers in relation to safe child occupant travel in the Emirate of Dubai in the United Arab Emirates (UAE). A community survey was completed by 786 participants who were responsible for the safety of 1614 children (aged 10 years and younger). The survey included questions related to the type, frequency and appropriateness of restraint use for their eldest child.

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Many-body localization in interacting quantum systems can be cast as a disordered hopping problem on the underlying Fock-space graph. A crucial feature of the effective Fock-space disorder is that the Fock-space site energies are strongly correlated-maximally so for sites separated by a finite distance on the graph. Motivated by this, and to understand the effect of such correlations more fundamentally, we study Anderson localization on Cayley trees and random regular graphs, with maximally correlated disorder.

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Objective: To understand which users' characteristics influence their preferences in the selection of vehicle seating configurations and positions across different traveling scenarios involving a fully automated vehicle (FAV).

Methods: Participants ( = 730) completed an online survey in which they were asked to imagine traveling in a FAV across three hypothetical scenarios. Participants were asked to select between five different seating configurations and four positions for each scenario and about their anthropometry and their driving/riding experience.

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Bicyclists are vulnerable road users as they are not protected during a road collision. Although numerous studies have been conducted to understand the parameters contributing to bicyclist's injury severity, most of these studies have focused on the relationship between crash severity and road, environmental, vehicle and human demographic parameters. No study has been found that investigated the relationship of bicyclist's injury severity with speed and mass of both vehicles, as well as other crash dynamics aspects.

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Metabolic alterations in cancer represent convergent effects of oncogenic mutations. We hypothesized that a metabolism-restricted genetic screen, comparing normal primary mouse hematopoietic cells and their malignant counterparts in an ex vivo system mimicking the bone marrow microenvironment, would define distinctive vulnerabilities in acute myeloid leukemia (AML). Leukemic cells, but not their normal myeloid counterparts, depended on the aldehyde dehydrogenase 3a2 (Aldh3a2) enzyme that oxidizes long-chain aliphatic aldehydes to prevent cellular oxidative damage.

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The objective of this study was to address the uptake of safer vehicles and in-vehicle technologies among older adults through a better understanding of extent and use of safer vehicles and awareness/acceptance of new vehicle technologies. Data were collected from a sample of 501 active older drivers (those who drove at least once a week) through telephone surveys. The sample included experienced and active drivers aged between 65 and 92 years (median 73 years).

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This study aimed to understand seating configuration and position preferences in a fully automated vehicle (FAV) across 7 hypothetical traveling scenarios. Participants completed an online survey in which they were asked to imagine traveling in an FAV across 7 hypothetical traveling scenarios and asked to select 1 of 5 seating configurations and 1 of 4 seating positions for themselves and for any additional occupants. Furthermore, participants were asked to indicate any activities that they and any additional occupants would engage in and whether they would be willing to wear a different seat belt in an FAV while seated in a non-forward-facing mode or while reclined.

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Angiosperm mitochondrial (mt) genes are generally slow-evolving, but multiple lineages have undergone dramatic accelerations in rates of nucleotide substitution and extreme changes in mt genome structure. While molecular evolution in these lineages has been investigated, very little is known about their mt function. Some studies have suggested altered respiration in individual taxa, although there are several reasons why mt variation might be neutral in others.

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Motor patterns in legged vertebrates show modularity in both young and adult animals, comprising motor synergies or primitives. Are such spinal modules observed in young mammals conserved into adulthood or altered? Conceivably, early circuit modules alter radically through experience and descending pathways' activity. We analyze lumbar motor patterns of intact adult rats and the same rats after spinal transection and compare these with adult rats spinal transected 5 days postnatally, before most motor experience, using only rats that never developed hind limb weight bearing.

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We consider some aspects of a standard model employed in studies of many-body localization: interacting spinless fermions with quenched disorder, for non-zero filling fraction, here on d-dimensional hypercubic lattices. The model may be recast as an equivalent tight-binding model on a 'Fock-space (FS) lattice' with an extensive local connectivity. In the thermodynamic limit exact results are obtained for the distributions of local FS coordination numbers, FS site-energies, and the density of many-body states.

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Objective: The objective of this study is to describe key risks related to dooring collisions on roads in mixed function activity centers by examining video footage recorded onboard the bicycles of cyclists riding through this road environment. The study aims to enhance our understanding of the risk associated with cyclist door collisions on these roads and to provide a focus for future studies that aim to identify measures that enhance cyclist safety.

Method: The study measured 4 key risk exposures (per hour and kilometer), namely, on-street parked cars and 3 conditions associated with parked cars being accessed or egressed: door opened (a) after the cyclist passes (give-way event); (b) in the path of the cyclist without collision (obstruction event); and (c) in the path of the cyclist with collision (collision event).

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Melbourne, Australia has the largest tram/streetcar network in the world including the largest mixed traffic tram operating environment. Therefore, Melbourne tram drivers are responsible for controlling one of the heaviest vehicles on road ranging from shared tram lanes to exclusive tram lanes. In addition to different tram lane configurations, tram drivers need to follow different traffic signal phases at intersections including tram priority signals as well as need to serve passengers at various types of closely spaced tram stops.

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Stem cells respond to the physicochemical parameters of the substrate on which they grow. Quantitative material activity relationships - the relationships between substrate parameters and the phenotypes they induce - have so far poorly predicted the success of bioactive implant surfaces. In this report, we screened a library of randomly selected designed surface topographies for those inducing osteogenic differentiation of bone marrow-derived mesenchymal stem cells.

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Mitochondrial dynamics and distribution are critical for supplying ATP in response to energy demand. CLUH is a protein involved in mitochondrial distribution whose dysfunction leads to mitochondrial clustering, the metabolic consequences of which remain unknown. To gain insight into the role of CLUH on mitochondrial energy production and cellular metabolism, we have generated CLUH-knockout cells using CRISPR/Cas9.

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Roadside advertising has the potential to create a crash risk for drivers as it may distract attention from driving at critical times. In an on-road instrumented vehicle study, we examined if and how static advertising billboards affect drivers' situation awareness across different driving environments. Nineteen fully licensed drivers drove an instrumented vehicle around a 38 km urban test route comprising freeway, busy urban retail and arterial road sections.

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Here we apply a control theoretic view of movement to the behavior of human locomotion with the goal of using perturbations to learn about subtask control. Controlling one's speed and maintaining upright posture are two critical subtasks, or underlying functions, of human locomotion. How the nervous system simultaneously controls these two subtasks was investigated in this study.

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Seed germination is a vital developmental transition for production of progeny by sexual reproduction in spermatophytes. Quiescent cells in nondormant dry embryos are reawakened first by imbibition and then by perception of germination triggers. Reanimated tissues enter into a germination program requiring energy for expansion growth.

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