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    Exposure to fine particulate matter (PM2.5) during landscape fire events and the risk of cardiorespiratory emergency department attendances: a time-series study in Perth, Western Australia

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    Background Landscape fires (LFs) are the main source of elevated particulate matter (PM2.5) in Australian cities and towns. This study examined the associations between daily exposure to fine PM2.5 during LF events and daily emergency department attendances (EDA) for all causes, respiratory and cardiovascular outcomes. Methods Daily PM2.5 was estimated using a model that included PM2.5 measurements on the previous day, remotely sensed aerosols and fires, hand-drawn tracing of smoke plumes from satellite images, fire danger ratings and the atmosphere venting index. Daily PM2.5 was then categorised as high (≥99th percentile), medium (96th–98th percentile) and low (≤95th percentile). Daily EDA for all-cause and cardiorespiratory conditions were obtained from the Western Australian Emergency Department Data Collection. We used population-based cohort time-series multivariate regressions with 95% CIs to assess modelled daily PM2.5 and EDA associations from 2015 to 2017. We estimated the lag-specific associations and cumulative risk ratios (RR) at lags of 0–3 days, adjusted for sociodemographic factors, weather and time. Results All-cause EDA and overall cardiovascular presentations increased on all lagged days and up to 5% (RR 1.05, 95% CI 1.03 to 1.06) and 7% (RR 1.07, 95% CI 1.01 to 1.12), respectively, at the high level. High-level exposure was also associated with increased acute lower respiratory tract infections at 1 (RR 1.19, 95% CI 1.10 to 1.29) and 3 (RR 1.17, 95% CI 1.10 to 1.23) days lags and transient ischaemic attacks at 1 day (RR 1.25, 95% CI 1.02 to 1.53) and 2 (RR 1.20, 95% CI 1.01 to 1.42) days lag. Conclusions Exposure to PM2.5 concentrations during LFs was associated with an increased risk of all-cause EDA, overall EDA cardiovascular diseases, acute respiratory tract infections and transient ischaemic attacks

    Thoracic Electrical Impedance Tomography—The 2022 Veterinary Consensus Statement

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    Electrical impedance tomography (EIT) is a non-invasive real-time non-ionising imaging modality that has many applications. Since the first recorded use in 1978, the technology has become more widely used especially in human adult and neonatal critical care monitoring. Recently, there has been an increase in research on thoracic EIT in veterinary medicine. Real-time imaging of the thorax allows evaluation of ventilation distribution in anesthetised and conscious animals. As the technology becomes recognised in the veterinary community there is a need to standardize approaches to data collection, analysis, interpretation and nomenclature, ensuring comparison and repeatability between researchers and studies. A group of nineteen veterinarians and two biomedical engineers experienced in veterinary EIT were consulted and contributed to the preparation of this statement. The aim of this consensus is to provide an introduction to this imaging modality, to highlight clinical relevance and to include recommendations on how to effectively use thoracic EIT in veterinary species. Based on this, the consensus statement aims to address the need for a streamlined approach to veterinary thoracic EIT and includes: an introduction to the use of EIT in veterinary species, the technical background to creation of the functional images, a consensus from all contributing authors on the practical application and use of the technology, descriptions and interpretation of current available variables including appropriate statistical analysis, nomenclature recommended for consistency and future developments in thoracic EIT. The information provided in this consensus statement may benefit researchers and clinicians working within the field of veterinary thoracic EIT. We endeavor to inform future users of the benefits of this imaging modality and provide opportunities to further explore applications of this technology with regards to perfusion imaging and pathology diagnosis

    Distribution and habitat partitioning of cetaceans (Mammalia: Cetartiodactyla) in the Bohol Sea, Philippines.

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    Understanding broad-scale species distribution and finer-scale ecological interactions is essential for conservation. We assessed species richness, distribution, habitat use and interspecific associations of cetacean in the Bohol Sea, Philippines. During 72 days of dedicated survey (2010 - 2013), we encountered 12 species of cetacean in 291 sightings, 16.8% of which involved mixed species. We used maximum entropy (MaxEnt) models to assess species’ habitat suitability and found slope and distance from the coast to be influential contributors to cetacean distribution. To explore habitat use, through foraging ecology and niche segregation of sympatric species, we compared behavioral budgets across species and found significant differences (chi-sq = 21.44; p-value = 0.044). We then used GLMs to determine the foraging likelihood in relation to oceanographic features, group size and presence of associated species. Results from model selection complimented those derived from MaxEnt. However, some inter-specific exclusion behavior might also occur. Overall, our study suggests that the Bohol Sea supports a high cetacean biodiversity while more complex inter-specific dynamics might further shape species’ ecological niches. These results highlight the importance of multi-species ecology and can be used to develop management actions

    Behavioural and neural responses of crabs show evidence for selective attention in predator avoidance

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    Selective attention, the ability to focus on a specific stimulus and suppress distractions, plays a fundamental role for animals in many contexts, such as mating, feeding, and predation. Within natural environments, animals are often confronted with multiple stimuli of potential importance. Such a situation significantly complicates the decision-making process and imposes conflicting information on neural systems. In the context of predation, selectively attending to one of multiple threats is one possible solution. However, how animals make such escape decisions is rarely studied. A previous field study on the fiddler crab, Gelasimus dampieri, provided evidence of selective attention in the context of escape decisions. To identify the underlying mechanisms that guide their escape decisions, we measured the crabs’ behavioural and neural responses to either a single, or two simultaneously approaching looming stimuli. The two stimuli were either identical or differed in contrast to represent different levels of threat certainty. Although our behavioural data provides some evidence that crabs perceive signals from both stimuli, we show that both the crabs and their looming-sensitive neurons almost exclusively respond to only one of two simultaneous threats. The crabs’ body orientation played an important role in their decision about which stimulus to run away from. When faced with two stimuli of differing contrasts, both neurons and crabs were much more likely to respond to the stimulus with the higher contrast. Our data provides evidence that the crabs’ looming-sensitive neurons play an important part in the mechanism that drives their selective attention in the context of predation. Our results support previous suggestions that the crabs’ escape direction is calculated downstream of their looming-sensitive neurons by means of a population vector of the looming sensitive neuronal ensemble

    Axial length distributions in patients with genetically confirmed inherited retinal diseases

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    Purpose: We investigated axial length (AL) distributions in inherited retinal diseases (IRDs), comparing them with reference cohorts. Methods: AL measurements from IRD natural history study participants were included and compared with reference cohorts (TwinsUK, Raine Study Gen2-20, and published studies). Comparing with the Raine Study cohort, formal odds ratios (ORs) for AL ≥ 26 mm or AL ≤ 22 mm were derived for each IRD (Firth's logistic regression model, adjusted for age and sex). Results: Measurements were available for 435 patients (median age, 19.5 years). Of 19 diseases, 10 had >10 participants: ABCA4 retinopathy; CNGB3- and CNGA3-associated achromatopsia; RPGR-associated disease; RPE65-associated disease; blue cone monochromacy (BCM); Bornholm eye disease (BED); TYR- and OCA2-associated oculocutaneous albinism; and GPR143-associated ocular albinism. Compared with the TwinsUK cohort (n = 322; median age, 65.1 years) and Raine Study cohort (n = 1335; median age, 19.9 years), AL distributions were wider in the IRD groups. Increased odds for longer ALs were observed for BCM, BED, RPGR, RPE65, OCA2, and TYR; increased odds for short AL were observed for RPE65, TYR, and GPR143. In subanalysis of RPGR-associated disease, longer average ALs occurred in cone–rod dystrophy (n = 5) than rod–cone dystrophy (P = 0.002). Conclusions: Several diseases showed increased odds for longer AL (highest OR with BCM); some showed increased odds for shorter AL (highest OR with GPR143). Patients with RPE65- and TYR-associated disease showed increased odds for longer and for shorter eyes. Albinism genes were associated with different effects on AL. These findings add to the phenotype of IRDs and may yield insights into mechanisms of refractive error development

    Dominance, diversity, and niche breadth in arbuscular mycorrhizal fungal communities

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    Classical theory identifies resource competition as the major structuring force of biotic communities and predicts that (i) levels of dominance and richness in communities are inversely related, (ii) narrow niches allow dense “packing” in niche space and thus promote diversity, and (iii) dominants are generalists with wide niches, such that locally abundant taxa also exhibit wide distributions. Current empirical support, however, is mixed. We tested these expectations using published data on arbuscular mycorrhizal (AM) fungal community composition worldwide. We recorded the expected negative relationship between dominance and richness and, to a degree, the positive association between local and global dominance. However, contrary to expectations, dominance was pronounced in communities where more specialists were present and, conversely, richness was higher in communities with more generalists. Thus, resource competition and niche packing appear to be of limited importance in AM fungal community assembly; rather, patterns of dominance and diversity seem more consistent with habitat filtering and stochastic processes

    Knowledge transfer-oriented deep neural network framework for estimation and forecasting the state of health of the Lithium-ion batteries

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    This paper proposes an efficient data-driven framework for estimating and forecasting the state of health (SOH) of Lithium-ion (Li-ion) batteries. The proposed framework is established upon a deep neural network (DNN) model, knowledge transfer asset, and autoregressive integrated moving average (ARIMA) forecasting model. The knowledge transfer property reduces the required data for training the model and hence the approach becomes fast and good fit for forecasting the SOH of Li-ion batteries. Among various possibilities, the most efficient training features are picked by Pearson correlation coefficient and least absolute shrinkage and selection operator (LASSO) regression. To suppress existing noises, Savitzky-Golay filter is applied to the signals. The proposed framework allows to use a limited portion of the dataset (about 25 %) for training phase and guarantees high accuracy (almost 96 %) of estimation according to coefficient of determination. Mean squared error (MSE) of the estimations is 0.00075 which is small enough to trust on results. MSE of the model not only during training via 25 % of data is measured, but also after training by 20 % and 30 % of dataset is calculated as well. Training by 20 % of dataset results in a great downfall in the model performance with a 26.6 % rise in the MSE value. Surprisingly, training the model with 30 % portion of the dataset does not add any noticeable accuracy to the model. This study confirms that the transfer learning property and DNN model combination could achieve a dramatic reduction of the dataset portion for training purpose

    Inclusion body myositis: The interplay between ageing, muscle degeneration and autoimmunity

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    Inclusion body myositis (IBM) is a slowly progressive muscle disease affecting ageing individuals. IBM presents with a distinctive pattern of weakness involving the quadriceps and finger flexor muscles, although other muscles including pharyngeal muscles become affected over time. Pathological hallmarks of IBM include autoimmune features, including endomysial infiltration by highly differentiated T cells, as well as degenerative features marked by intramyofibre protein aggregates organised into inclusion bodies. Despite some progress in understanding the cellular pathways involved in IBM, it remains untreatable, and the progression of the disease leads to progressive weakness, disability, wheelchair dependency and loss of independence. Therefore, there is an urgent need to improve our understanding of the underlying mechanisms and pathways involved in this disease to identify new treatment targets. Here, we discuss the current understanding of aetiopathogenesis, the interrelationship between autoimmunity and degeneration, and how ageing is a major influencer of both these features

    Rethinking customer engagement design: Using customer-mobilized engagement (CME) to grow business networks

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    The purpose of this paper is to propose a conceptual framework of customer-mobilized engagement (CME) pathways where customers actively identify, engage, and mobilize hidden (new) actors (and their resources) who are beyond the reach of the focal organization. As a large proportion of value stems from connections with multiple business networks, an organization's customer network becomes an important strategic asset contributing to competitive advantage and survival. Taking a propositional approach, we conceptualize the CME pathway and elaborate on factors critical to CME drawing on two organizations for illustrative purposes. We develop three propositions explaining how customer-mobilized engagement of hidden (new) actors, resources, and engagement platforms connect dynamically via the mobilizing customer. The reinterpreted communicative value proposition increases the contribution of hidden actors and enhances and expands value outcomes for actors within the CME pathway including increased sustainable competitive advantage for the focal organization. Adopting CME adds new resources, in different ways to deliver value to an organization's diverse business streams and grow their business networks. The CME pathway provides industrial marketing managers with an agile tool to guide the design of their offerings which can adapt across business contexts and time as the social, economic, political and technological environment changes

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