Using a Lubachevsky-Stillinger-like growth algorithm combined with biased SWAP Monte Carlo and transient degrees of freedom, we generate ultradense disordered jammed ellipse packings. For all aspect ratios α, these packings exhibit significantly smaller intermediate-wavelength density fluctuations and greater local nematic order than their less-dense counterparts. The densest packings are disordered despite having packing fractions ϕ(α) that are within less than 0.
View Article and Find Full Text PDFBackground: The incidence of silicosis has increased due to occupational silica exposure from artificial stone, with no treatments proven to halt or reverse the disease. Whole lung lavage (WLL) involves the instillation of fluid into the lungs to wash out silica particles and disease-causing inflammatory cells. This study aimed to determine the feasibility, safety, and possible benefit of WLL in patients with artificial stone silicosis.
View Article and Find Full Text PDFObjectives: Workers in the stone benchtop industry in Australia are at high risk of silicosis due to exposure to respirable crystalline silica (RCS) from the dry processing of artificial stone. In Victoria, Australia, a multifaceted response including education, regulatory changes, inspection site visits, and occupational health screening programme began in 2019. We aimed to review the success of this approach to safety practices in the industry.
View Article and Find Full Text PDFFetal microchimerism, the presence of fetal cells in maternal tissues, has garnered interest for its potential role in maternal physiology. In this study, we aimed to explore the impact of fetal microchimeric cells on maternal lung health following term and preterm delivery, particularly in the context of infection-induced preterm birth and subsequent allergic challenges. We characterized the immune cells in maternal lungs using a transgenic mouse model (mT+ Ve, Td Tomato) and high dimensional mass cytometry (CyTOF) techniques.
View Article and Find Full Text PDFInt Arch Occup Environ Health
December 2024
Purpose: This study aimed to use workers' compensation (WC) data to explore the impact of the extreme bushfires on injury/disease claim rates amongst first responders (FR) compared with other occupations and off-seasons.
Methods: Data on WC claims for FR (ambulance officers, paramedics, firefighters, police) and other occupations were obtained from WorkSafe Victoria 2005-2022. Negative binomial regression models adjusting for age, gender and number of employed people were used to estimate incident rate ratios of all injury/disease, mental, musculoskeletal and respiratory claims among FR in summer and extreme bushfires compared to off-season/summer and other occupations.
Background: Wildfire smoke contains numerous hazardous air pollutants which pose serious health risks to humans. Despite this, there has been a limited focus on the assessment of the acute physiological and longer-term respiratory effects of wildfire exposure on firefighters and other emergency workers. Therefore, we undertook a systematic review of the evidence about the respiratory impacts of occupational wildfire smoke exposure among wildfire fighters (WFF).
View Article and Find Full Text PDFObjectives: Autoimmune disorders are multifactorial but occupational exposures have long been implicated, including respirable crystalline silica (RCS). A modern epidemic of silicosis is emerging internationally, associated with dry processing of engineered stone with high (>90%) RCS content. We aimed to investigate the prevalence of clinical autoimmune disease and common autoantibodies in exposed workers.
View Article and Find Full Text PDFUsing hybrid molecular dynamics/SWAP Monte Carlo (MD/SMC) simulations, we show that while the terminal relaxation times τ(ϕ) for FIRE energy minimization of soft-sphere glasses can decrease by orders of magnitude as sample equilibration proceeds and the jamming density ϕ_{J} increases, they always scale as τ(ϕ)∼(ϕ_{J}-ϕ)^{-2}∼[Z_{iso}-Z_{ms}(τ)]^{-2}, where Z_{iso}=2d and Z_{ms}(τ) is the average coordination number of particles satisfying a minimal local mechanical stability criterion (Z≥d+1) at the top of the final potential-energy-landscape (PEL) sub-basin the system encounters. This scaling allows us to collapse τ datasets that look very different when plotted as a function of ϕ, and to address a closely related question: how does the character of the PEL basins that dense thermal glasses most typically occupy evolve as the glasses age at constant ϕ and T?
View Article and Find Full Text PDFEngineered stone-associated silicosis is characterised by a rapid progression of fibrosis linked to a shorter duration of exposure. To date, there is lack of information about molecular pathways that regulates disease development and the aggressiveness of this form of silicosis. Therefore, we compared transcriptome responses to different engineered stone samples and standard silica.
View Article and Find Full Text PDFBackground And Objective: Chest x-ray (CXR) remains a core component of health monitoring guidelines for workers at risk of exposure to crystalline silica. There has however been a lack of evidence regarding the sensitivity of CXR to detect silicosis in artificial stone benchtop industry workers.
Methods: Paired CXR and high-resolution computed tomography (HRCT) images were acquired from 110 artificial stone benchtop industry workers.
We observe homogeneous crystallization in simulated high-dimensional (d>3) liquids that follow physically realistic dynamics and have system sizes that are large enough to eliminate the possibility that crystallization was induced by the periodic boundary conditions. Supercooled four-dimensional (4D) Lennard-Jones (LJ) liquids maintained at zero pressure and constant temperatures 0.59
Two transcriptional co-repressors physically interact with a transcription factor that is known to recruit a multi-protein complex, which promotes the repression of seed maturation genes by depositing trimethylation marks on lysine 27 of the histone 3 tails.
View Article and Find Full Text PDFBackground: The Perceived Stress Scale (PSS-10) has been used in a range of occupational cohorts, but only recently in stone benchtop workers undergoing screening for silicosis. The aim of this study was to compare psychometric properties of the PSS-10 in stone benchtop workers amongst those born overseas or who used an interpreter.
Methods: Stone benchtop workers in Melbourne, Australia completed the PSS-10 as part of their occupational screening for silicosis.
Most mosquito and midge species use hearing during acoustic mating behaviors. For frog-biting species, however, hearing plays an important role beyond mating as females rely on anuran calls to obtain blood meals. Despite the extensive work examining hearing in mosquito species that use sound in mating contexts, our understanding of how mosquitoes hear frog calls is limited.
View Article and Find Full Text PDFJumping spiders have extraordinary vision. Using multiple, specialized eyes, these spiders selectively gather and integrate disparate streams of information about motion, color, and spatial detail. The saccadic movements of a forward-facing pair of eyes allow spiders to inspect their surroundings and identify objects.
View Article and Find Full Text PDFMotivated in part by the recent observation of liquid glass in suspensions of ellipsoidal colloids, we examine the structure of jammed two-dimensional ellipse packings over a much wider range of particle aspect ratios (, the ratio of the major and minor axis lengths) than has been previously attempted. We determine the jamming densities () to high precision, and find empirical analytic formulae that predict () to within less than 0.1% for all 1≤≤10, for three different particle dispersities.
View Article and Find Full Text PDFObjectives: High silica content artificial stone has been found to be associated with silicosis among stone benchtop industry (SBI) workers. The objectives of this study were to determine the prevalence of and risk factors for silicosis among a large cohort of screened SBI workers, and determine the reliability of respiratory function testing (RFT) and chest x-ray (CXR) as screening tests in this industry.
Methods: Subjects were recruited from a health screening programme available to all SBI workers in Victoria, Australia.
Using discrete element method simulations, we show that the settling of frictional cohesive grains under ramped-pressure compression exhibits strong history dependence and slow dynamics that are not present for grains that lack either cohesion or friction. Systems prepared by beginning with a dilute state and then ramping the pressure to a small positive value P_{final} over a time τ_{ramp} settle at packing fractions given by an inverse-logarithmic rate law, ϕ_{settled}(τ_{ramp})=ϕ_{settled}(∞)+A/[1+Bln(1+τ_{ramp}/τ_{slow})]. This law is analogous to the one obtained from classical tapping experiments on noncohesive grains, but crucially different in that τ_{slow} is set by the slow dynamics of structural void stabilization rather than the faster dynamics of bulk densification.
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