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Recommendations for defining disturbed flow as laminar, transitional, or turbulent in assays of hemostasis and thrombosis: communication from the ISTH SSC Subcommittee on Biorheology
No full textBlood flow is vital to life, yet disturbed flow has been linked to atherosclerosis, thrombosis, and endothelial dysfunction. The commonly used hemodynamic descriptor “disturbed flow” found in disease and medical devices is not clearly defined in many studies. However, the specific flow regime—laminar, transitional, or turbulent—can have very different effects on hemostasis, thrombosis, and vascular health. Therefore, it remains important to clinically identify turbulence in cardiovascular flow and to have available assays that can be used to study effects of turbulence. The objective of the current communication was to 1) provide clarity and guidance for how to clinically identify turbulence, 2) define standard measures of turbulence that can allow the recreation of flow conditions in a benchtop assay, and 3) review how cells and proteins in the blood can be impacted by turbulence based on current literature.Funding information D.L.B. acknowledges funding support from National Institutes of Health; National Heart, Lung, and Blood Institute (R01HL164424); and National Institute of Biomedical Imaging and Bioengineering (R21EB034579). E.E.G. receives funding from the National Health and Medical Research Council of Australia.Peer-reviewe
Isolation, identification, and characterisation of the malachite green detoxifying bacterial strain Bacillus pacificus ROC1 and the azoreductase AzrC
No full textMalachite green (MG) is used as a dye for materials such as wood, cotton, and nylon, and is used in aquaculture to prevent fungal and protozoan diseases. However, it is highly toxic, with carcinogenic, mutagenic, and teratogenic properties, resulting in bans worldwide. Despite this, MG is still frequently used in many countries due to its efficacy and economy. MG is persistent in the environment and so requires degradative intervention. In this work we isolated Bacillus pacificus ROC1 strain from a salt flat in Pakistan that had the ability to aerobically detoxify MG, as determined by bacterio- and phyto-toxicity assays. We demonstrate immobilized B. pacificus ROC1 can effectively detoxify MG, which highlights a potential method for its biodegradation. Genomic sequencing identified three candidate azo-reductases within B. pacificus ROC1 that could be responsible for the MG-degrading activity. These were cloned, expressed and purified from Escherichia coli, with one (AzrC), catalyzing the reduction of MG to leuco-MG in vitro. AzrC was crystallised and MG was captured within the active site in a Michaelis complex, providing structural insight into the reduction mechanism. Altogether, this work identifies a bacterium capable of aerobically degrading a major industrial pollutant and characterizes the molecular basis for this activity.This research was undertaken in part using the MX2 beamline at the Australian Synchrotron, which is part of ANSTO, and made use of the Australian Cancer Research Foundation (ACRF) detector. We acknowledge the ARC Centre of Excellence for Innovations in Peptide and Protein Science (CE200100012) and the ARC Centre of Excellence in Synthetic Biology (CE200100029) for funding.Peer-reviewe
Violent Impacts: How Power and Inequality Shape the Concussion Crisis
No full textConcerns regarding brain injury in sport have escalated into what is often termed a “concussion crisis,” fueled by high-profile lawsuits and deaths. Although athletes are central figures in this narrative, they comprise only a small proportion of the people who experience brain injuries, while other high-risk groups—including victims of domestic violence and police brutality—are all too often left out of the story. In Violent Impacts, Kathryn Henne and Matt Ventresca examine what is and what isn’t captured in popular discourse, scrutinizing how law, science, and social inequalities shape depictions and understandings of brain injury. Drawing on research carried out in Australia, Canada, and the United States, they illustrate how structural violence centers certain bodies as part of the concussion crisis while pushing others to the margins.Peer-reviewe
Prosecuting international crimes against children: prospects for intergenerational justice in international security
No full textIn my contribution to the 2015 special issue (Jacob Citation2015),Footnote1 I argued that security studies are structured on themes of statehood, power, and sovereignty in ways that foreclose theoretical space to integrate children’s experiences and contributions. I called for a practice-based reading of the ‘field’ of security in which children’s presence in the wider social-political landscape could be researched. I argued that theorising childhood as a bounded category would abstract the research agenda from the wider contours of conflict and insecurity and restrict our view to narrow themes such as child soldiers and war victims. Furthermore, violent conflict represents a ‘radical realignment of the entire social space’ in which children’s constitutive presence cannot be extricated (Jacob Citation2015, 24). These insights, I believe, still hold, and I briefly consider more recent developments in the application of international law in armed conflict to illustrate...Peer-reviewe
Can Peter Dutton flip Labor voters to rewrite electoral history? It might just work
No full textThey are neither as leafy nor as affluent as much of the Liberal heartland, but Peter Dutton believes the outer ring-roads of Australia’s capitals provide the most direct route to power. He has been telling his MPs these once-safe Labor-voting suburbs are where the 2025 election can be won.Not peer-reviewe
Textual dimensions of sustainability information, stock price informativeness, and proprietary costs: Evidence from integrated reports
No full textWe examine whether integrated report quality, IRQ, is negatively associated with stock price synchronicity, an inverse measure of firm-specific information, and the extent to which the relation between IRQ and synchronicity is attenuated by proprietary costs. We measure IRQ using machine-based textual analysis along four dimensions: textual attributes, topical content, integrated reporting capitals, and financial versus sustainability information. We find that measures of IRQ based on seven textual attributes are negatively related to synchronicity, which is consistent with higher quality text containing more firm-specific content. Using PhraseLDA to identify topics in integrated reports, we find that contents related to the three most common categories—governance, performance, and risks and opportunities—are negatively associated with synchronicity. We find similar results for all integrated report capitals, except manufactured capital. Further, we find that sustainability information has a larger negative association with synchronicity than financial information. We also find that proprietary costs stemming from product market competition attenuate the association between IRQ and synchronicity, which suggests the informativeness of integrated reports varies with a firm's competitive environment. Our results may inform the International Sustainability Standards Board as it considers the role of the Integrated Reporting Framework in developing sustainability standards.In June 2022, the EFRAG Financial Reporting Board (EFRAG FRB) approved the addition of a project on the connectivity between financial and sustainability-related disclosures to EFRAG's proactive research agenda. In February 2023, the EFRAG FRB approved the formation of an advisory panel on the connectivity between financial reporting and sustainability reporting (EFRAG CAP) to support the research activities and advise the EFRAG Financial Reporting Technical Expert Group (FR TEG) on the project.13 In February 2024, the EFRAG FR TEG and Sustainability Reporting Technical Expert Group released the \u201CConnectivity Principles Issues Paper\u201D based on the discussions from their joint public meeting held in December 2023. This report highlights that between 2013 and 2017 the principle of connectivity has been considered by more than 4000 European firms that annually prepared an integrated report in terms of the Framework.Alongside the EU developments, in June 2021, the IIRC and SASB merged to form the Value Reporting Foundation (VRF).14 In August 2022, the International Financial Reporting Standards Foundation (IFRSF) consolidated the VRF into the IFRSF to support the work of the Foundation's newly established International Sustainability Standards Board (ISSB), a sister board to the International Accounting Standards Board (IASB), to develop a comprehensive global baseline of sustainability disclosures for the capital markets.15 Our sample period is from 2011 to 2017. We begin in 2011 because integrated reporting became mandatory in South Africa for JSE primary listed firms in 2010 and the EY integrated reporting awards commenced in 2012 for 2011 reports. Our sample is based on the top 100 JSE firms by market capitalization for which EY evaluates integrated report quality annually.39 We obtain integrated reports from firms\u2019 websites and remaining data from Compustat Global, Refinitiv Worldscope, and Refinitiv Datastream.Peer-reviewe
On-Chip Stimulated Brillouin Scattering to Linearize a Dual-Parallel Mach-Zehnder Modulator
No full textMicrowave photonics offers great potential for wideband systems, but link linearity remains limited and must be overcome to have the dynamic range required for many applications. Here, we propose and demonstrate the linearization of a Dual-Parallel Mach-Zehnder Modulator by frequency-selectively controlling the phase and amplitude of the carrier utilizing a dual-pump, narrowband stimulated Brillouin scattering scheme. Measurements using a single-mode fiber and chalcogenide waveguides on a chip are presented. As a result, a suppression of third-order distortion terms of 27 dB is experimentally obtained, and a spurious free dynamic range improvement of 9 dB using fiber and 4.5 dB using a chalcogenide chip, respectively. On-chip measurements enable the possibility of a fully integrated system, significantly reducing the overall footprint.Peer-reviewe
Recent Developments in Applying Quantile Regression for Missing Data in Longitudinal Studies
No full textIn this thesis, we propose new approaches based on a quantile regression model to handle missing data in longitudinal studies. In Chapters 2 and 3, we develop univariate quantile regression imputation models for longitudinal data that may exhibit population heterogeneity. In Chapter 4, we propose a multivariate quantile regression imputation model capable of handling missing values across multiple responses, as well as imputations for censored observations. Our proposed models are evaluated using three HIV longitudinal datasets collected from the Multicenter AIDS Cohort Study and the Women's Interagency HIV Study (also known as the MACS/WIHS Combined Cohort Study). We believe these models can also be applied to other longitudinal datasets. All our models are built within the Bayesian framework, with estimation and inference implemented using the Markov Chain Monte Carlo (MCMC) procedure.
In Chapter 2, considering the presence of population heterogeneity in the longitudinal data, we construct a latent class mixture quantile regression model for imputation. To address missing values under the Missing Not at Random (MNAR) assumption, we propose an additional model to capture the missingness indicator, thereby facilitating the imputation of missing values. We test the proposed approach under various simulation settings, and find the proposed model consistently yields accurate parameter estimations across the simulation scenarios. The model is also evaluated using real data from the MACS study. Based on the real-data analysis results, we conclude that the model fit can be improved with the addition of a latent class structure when a clustering effect exists in the data.
In Chapter 3, we extend the imputation model introduced in Chapter 2 by incorporating semiparametric random effects terms, assuming a Dirichlet process prior. This imputation model can be treated as a semiparametric latent class mixture quantile regression model. Additionally, we include the same random effects terms in the model for the missingness indicator, thus building a shared-parameter model structure for MNAR. Simulation results demonstrate that the proposed model can not only provide consistent and accurate results for the estimation of parameters of interest, but can also recover the shape of the random effects terms when the response variable contains missing observations. We also test the proposed model using longitudinal data from the MACS HIV study. Compared to the model presented in Chapter 2, the Chapter 3 model returns a better fit.
In Chapter 4, we propose a multivariate imputation approach within the quantile regression framework to address missing values in multiple responses within longitudinal studies. This model is motivated by real data from the WIHS HIV study. The response variable, HIV viral load, contains missing values and is also subject to upper detection limits, which can be treated as left-censored observations. Other variables of interest, such as CD4 and CD8 cell counts, also contain missing observations. Additionally, we incorporate an autocorrelated error structure in the imputation model, as current values can be influenced by previous observations. We test the model under various simulation settings and show that our model can provide accurate and consistent parameter estimation results by imputing the missing observations and recovering the censored observations. In the real data setting, we assess our model's performance compared to models without autocorrelated error structures and those using multivariate linear mixed effects models as imputation models, and we find that our model yields a better fit.
In Chapter 5, we summarize the thesis and outline directions for future research
Sprinkle Magic on the Dance: Enriching a Verified Choreographic Language with a Simply Typed Lambda Calculus
No full textDistributed systems are ubiquitous but writing endpoint programs can be error-prone since mismatched message sending and receiving can lead to errors such as deadlock, where the system indefinitely awaits a message. Choreography offers a solution by providing a global description of how messages are exchanged among endpoints, where message mismatches are disallowed — a property called “deadlock-free by design”. The global choreography is then projected into process models for each endpoint, preserving the deadlock-free property. While many choreography languages focus on message exchange behaviors, few address the local computations occurring within endpoints. Most current languages assume local computation results or delegate them to external languages. While this offers a reasoning ground for studying message exchange behaviours of choreography, when it comes to writing a concrete choreography program, the former can only exchange literal values and the latter leads to cumbersome code due to the addition of an external computation program which typically involves conversions between choreography values and external data types. Hence in this thesis, we extend Kalas, a state-of-the-art choreography language with verified end- to-end compilation, with a local language Sprinkles, such that local computations are handled gracefully within a few lines of codes. Moreover, it also allows us to formally analyse the message exchange behaviours of choreography when local computations are considered. Our proofs show that the strong normalisation property of Sprinkles implies progress for the enriched Kalas, and that the combination of type soundness and strong normalisation of of Sprinkles implies type preservation for non-recursive, synchronous transitions in the enriched Kalas
A reference genome for the eastern bettong (Bettongia gaimardi)
No full textThe eastern or Tasmanian bettong (Bettongia gaimardi) is one of four extant bettong species and is listed as ‘Near Threatened’ by the IUCN. We sequenced short read data on the 10x system to generate a reference genome 3.46Gb in size and contig N50 of 87.36Kb and scaffold N50 of 2.93Mb. Additionally, we used GeMoMa to provide and accompanying annotation for the reference genome. The generation of a reference genome for the eastern bettong provides a vital resource for the conservation of the species.LWS is supported by the Australian BioCommons which is enabled by NCRIS via Bioplatforms Australia and the University of Sydney. RJE was supported by the Australian Research Council (LP180100721). The eastern bettong translocation program was funded by Australian Research Council Linkage Projects LP 110100126 and LP140100209, including cash and in-kind support from the ACT Government. ADM was supported by an Australian Research Council Future Fellowship (FT100100358) during the first phase of the bettong translocation project.Peer-reviewe