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Ward-delivered nasal high-flow oxygen and non-invasive ventilation are safe for people with acute respiratory failure: a cohort study
No full textBACKGROUND AND AIMS: Ward-delivered non-invasive respiratory supports (NIRS) (conventional oxygen therapy (COT), high-flow nasal oxygen (HFNO), continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV)), are often used to treat hospitalised patients with acute respiratory failure (ARF) both in high acuity and general wards. This study aimed to describe the processes of care adopted and examine patient outcomes from a specialist, ward-delivered NIRS service caring for people with COVID-19 in general wards or in a respiratory care unit (RCU). METHODS: A cohort study was undertaken including all consecutive patients admitted to a quaternary hospital with ARF secondary to COVID-19 and requiring ward-delivered NIRS between 28 February 2020 and 18 March 2022. NIRS use, processes of care and patient outcomes were examined. RESULTS: Six hundred sixty-eight patients were included, with 61% male and a mean age of 64 years (interquartile range 48-79 years). All received COT. Fifty eight percent of patients required additional NIRS: HFNO (36.2%), CPAP (19.8%) and NIV (1.9%). Eighty-two percent of patients had oxygen saturation targets documented. After the implementation of the RCU, significantly more nurse consultant-led CPAP prescriptions were initiated (P = 0.004) and fewer patients required review by the ICU team (P = 0.001) or transfer to ICU (P = 0.050). Forty-nine patients died (7.3%), with most (62.8%) being discharged directly home. CONCLUSION: This study highlights that ward-delivered NIRS is feasible and safe for people with COVID-19 and ARF. The combination of ward and RCU-delivered NIRS was particularly effective. Further research is required to determine the optimal models of respiratory care required for a broader range of patients and to understand how these should be implemented
The Relationship between the Economy and Environmental Attitudes: The Role of Folk Understandings of the Economy and its Functioning
No full text© 2025 Stephanie Marie RizioThe ongoing debate surrounding the relationship between economic conditions and environmental attitudes has been a focal point in recent psychological research and across the social sciences. Conventional perspectives suggest that actions toward the environment are contingent on a strongly performing economy, where pro-environmental efforts are seen as viable only when economic conditions are favorable. In contrast, less conventional perspectives, such as the green growth approach, posit that environmental actions are themselves an investment in the economy, fostering economic growth rather than hindering it. Despite the intensity of this discourse, the current empirical literature falls short in adequately elucidating emerging perspectives, particularly regarding the perceived compatibility between environmental actions and the economy.
While there has been some investigation of how the perception of the economy relates to environmental attitudes (e.g., Kachi et al., 2015; Kenny, 2017), these studies do not explore how individuals’ lay cognitions or intuitions about the economy and its functioning, known as “folk economics” (e.g., Caplan, 2006, 2008; Boyer & Petersen, 2018; Rubin, 2003; Williamson & Wearing, 1991), may deviate from what economic indicators convey and influence their attitudes towards the environment.
Through a comprehensive review of the literature on folk economics, this thesis argues that folk economic beliefs may influence support for pro-environmental initiatives, in addition to objective economic indicators such as GDP per capita and unemployment rates. We focus on two types: (1) the perception of economic conditions, referred to as the ‘perceptions of the state of the economy’ (PSE), shaped by individuals’ experiences and understandings of economic indicators, and (2) beliefs concerning the economic outcomes of environmental actions, termed ‘consequences of environmental action’ (CEA). For the latter, some individuals may hold the belief that environmental actions will impede economic progress (zero-sum folk economics), while others may believe that such actions will foster economic growth (positive-sum folk economics).
This thesis proposes a more nuanced framework for understanding the relationship between the economy and the environment. Using a combination of archival, survey, and experimental approaches across three studies in two culturally similar countries—Australia and Canada—lay economic beliefs, or folk economics (PSE and CEA) were found to shape environmental attitudes even in comparable contexts. Study 1 drew on over two decades of archival survey data (since 1990), with average sample sizes of N = 2,411 (Australia) and N = 1,986 (Canada). Study 3 was a cross-national survey (N = 157 Australia, N = 172 Canada), and Study 4 a cross-national experiment (N = 310 Australia, N = 283 Canada).
The results revealed divergent patterns between the two countries. While both showed tendencies toward conventional views of the economy–environment relationship, Australians more strongly endorsed zero-sum beliefs. In contrast, Canadians were more inclined toward less conventional perspectives, such as green growth, with a higher prevalence of positive-sum folk economic beliefs.
In addition, we speculate that the national differences found may be attributed to the composition of their respective mining industries and the resulting social and political effects. This underscores the significance of considering the psychological effects of country-specific contextual factors, even within ostensibly similar country settings, to understand the relationship between the economy and the environment more clearly
Mice expressing the autism-associated neuroligin-3 R451C variant exhibit increased mucus density and altered distributions of intestinal microbiota
No full textThe intestinal mucus layer protects the host from invading pathogens and is essential for maintaining a healthy mucosal microbial community. Alterations in the mucus layer and composition of mucus-residing microbiota in people diagnosed with autism may contribute to dysbiosis and gastrointestinal dysfunction. Although microbial dysbiosis based on sequencing data is frequently reported in autism, spatial profiling of microbes adjacent to the mucosa is needed to identify changes in bacterial subtypes in close contact with host tissues. Here, we analysed the spatial distribution of the mucin-2 protein using immunofluorescence as well as total bacteria, Bacteroidetes, Firmicutes phyla, and Akkermansia muciniphila using fluorescent in situ hybridization in mice expressing the autism-associated R451C variant in the Neuroligin-3 gene. We show that the Neuroligin-3 R451C variant increases mucus density adjacent to the distal ileal epithelium in mice. The relative density of total bacteria, Firmicutes, and A. muciniphila was increased whereas the density of Bacteroidetes was decreased closer to the epithelium in Neuroligin-3R451C mice. In summary, the autism-associated R451C variant in the Neuroligin-3 gene increases mucus density adjacent to the epithelium and alters microbial spatial distribution in the mouse distal ileum
Sex Differences in Perception of Economic and Dating Access
No full textMating and labor markets are fundamental drivers of societal dynamics. Yet, equity of access to these domains differs between the sexes due to numerous biological, economic, psychological, and socio-cultural factors. These inequalities and their impacts can accentuate perceptions, preferences, and behaviors of males and females in different ways. Utilizing a large cross-sectional sample of those currently engaged in the Australian mating market (n = 1072 online daters), we explored the impact of sex and individual differences on the perceptions of men's ease of access to a decent job in the labor market (opportunity), women's economic dependence on men (economic inequality), and relative reproductive opportunity (dating access) for both sexes. Our study identifies both sex differences and symmetries in socio-economic factors (such as education level and having offspring) correlating with the perceptions of both economic and dating market access for Australian online daters. Additionally, key resource endowment indicators (income and unemployment) also reflect differences in both sexes’ perceptions of both access and gender equity. That said, our study finds that perceptions of access to both (economic and mating) markets shows far greater variation based on biological age (especially for women) than any other factor
Before the beginning: International students’ negotiation of moving to Australia through Reddit or Xiaohongshu
No full textAs transient migrants, international students draw on diverse online information sources. While existing research primarily focuses on the information behaviours of international students who have already moved to their host countries, less attention has been given to those in the preparatory phase. Further, less attention has been paid to the different experiences students have in seeking out information prior to departure. To address these gaps, this study examines how international students use two distinct social media platforms – Reddit and Xiaohongshu – to seek information prior to their move. Reddit is a predominantly English-language platform, and Xiaohongshu is primarily used by Chinese-speaking communities. These platforms differ in user demographics and the nature of the content shared. Posts were collected over a six-month period on both platforms. Our qualitative content analysis of the posts explores differences in these online information sources. We identify barriers to finding credible information the pre-departure phase. We also highlight how students use crowd-sourced tools to navigate uncertainty around information quality and emphasize the benefits of such practice. This article contributes to the field of information behaviour by showcasing unique information experiences of pre-departure international students
Diagnostic accuracy of plasma p-tau217/Aβ42 for Alzheimer's disease in clinical and community cohorts
No full textINTRODUCTION: This study was undertaken to evaluate the diagnostic performance of a novel plasma phosphorylated tau (p-tau) 217/amyloid beta (Aβ) 42 ratio test for Alzheimer's disease (AD). METHODS: The diagnostic performance of the Lumipulse G plasma p-tau217/Aβ42 ratio was evaluated using Aβ and tau positron emission tomography (PET) as reference standards in a clinic cohort (n = 391) and a community cohort (n = 121). RESULTS: Plasma p-tau217/Aβ42 exhibited high performance for abnormal statuses of Aβ PET (area under the curve [AUC]: 0.963 to 0.966) and tau PET (AUC: 0.947 to 0.974), which were clinically equivalent to those of cerebrospinal fluid (CSF) p-tau181/Aβ42 and Aβ42/Aβ40 and higher than those of blood p-tau217, Aβ42/Aβ40, p-tau181, and p-tau181/Aβ42 in both clinic and community cohorts. Applying a two-cutoff approach improved the specificity without reducing sensitivity. The p-tau217/Aβ42 ratio had a lower intermediate percentage than p-tau217 alone in both clinic (10.6% vs 13.0%) and community (16.5% vs 31.4%) cohorts. DISCUSSION: Plasma p-tau217/Aβ42 has high performance in detecting cerebral AD pathologies, thus offering a promising tool for clinical diagnosis and community screening of AD. HIGHLIGHTS: Lumipulse G plasma p-tau217 and the p-tau217/Aβ42 ratio accurately identified abnormal Aβ and tau PET statuses in both clinical and community cohorts. The performance of plasma p-tau217 and p-tau217/Aβ42 ratio were equivalent to CSF tests. Plasma p-tau217/Aβ42 ratio outperformed p-tau217 alone in identifying Aβ PET positivity, and this superiority is more obvious in the community cohort, suggesting an advantage in the early diagnosis of AD. Two cut points of p-tau217/Aβ42 were established in the Chinese population for clinical laboratory and community screening uses
Mathematical modelling of Ciliary flows: Rotlet model
No full text© 2025 Siluvai Antony Selvan Antony RavichandranCilia are microscopic, hair-like structures in eukaryotic organisms, such as coral, mammals and algae, performing diverse functions including fluid pumping, locomotion, environmental sensing, and nutrient capture. Their active stirring close to the surface generates vortical flows, and various models have been employed to study such flows, ranging from capturing the detailed ciliary motion to approximating the multiple ciliary motions as a slip boundary. The former is computationally expensive for larger arrays, while the latter fails to resolve the individual ciliary flow, which is crucial for nutrient mixing in ciliated tissues. This study develops an efficient mathematical model using a point torque (rotlet) – a singularity solution of the Stokes equations – to capture flows generated by ciliary arrays and investigate particle transport at individual and array scales. Initially, we employ the rotlet model to represent a single cilium’s steady-state flow field in a semi-infinite domain, which is prevalent in coral surfaces. Then, we extend this model to confined geometries, such as those in the lung airway and oviduct, where we resolve the flows using the method of images and Fourier transforms. Using the developed flow model, we then analyse mass transport due to a single cilium near a no-slip boundary, combining a Langevin particle transport framework with a continuum model to reveal how flow enhances transport based on diffusivity, torque magnitude, and external shear alignment. Finally, we extend the developed flow model to the array scale based on the microfluidic observation of the coral Porites lutea. Through this setup, we investigate the influence of ciliary density, diffusivity, and external flow on mass transport to analyse concentration profiles and nutrient emission rates. This research provides insights into ciliated surfaces' near- and far-field flow characteristics, enabling detailed exploration of mass transport across the ciliated surface in diverse biological environments
Longitudinal Trajectories of Digital Cognitive Biomarkers for Multiple Sclerosis
No full textBACKGROUND: Cognitive impairment is one of the most common and debilitating symptoms of relapsing-remitting multiple sclerosis (RRMS). Digital cognitive biomarkers require less time and resources and are rapidly gaining popularity in clinical settings. We examined the longitudinal trajectory of the iPad-based Processing Speed Test (PST) and predictors of PST scores. METHODS: We prospectively enrolled RRMS patients between 2017 and 2021 across six Australian MS centres. Longitudinal data was analysed with mixed effect modelling and latent class mixed models. We then examined whether latent class group membership predicted confirmed decrease in correct PST responses. RESULTS: We recruited a total of 1093 participants, of which 724 had complete baseline data with a median follow up duration of 2 years. At a population level, PST trajectory was stable. A small practice effect was present up to the 4th visit. Age, baseline disability, T2 lesion volume, male sex and depression were associated with lower correct PST responses, whilst years of education and full/part-time employment were associated with more correct PST responses. We identified four latent class trajectories of PST. The worst latent class was typified by low baseline PST and lack of a practice effect. Being in the worst latent class was associated with a greater hazard of time to sustained 5% decrease in PST (HR 2.84, 95% CI 1.16-6.94, p = 0.02). CONCLUSION: Worse baseline cognitive performance and lack of a practice effect predicted future cognitive decline in RRMS
High-Resolution Geochronology and Geochemistry of Tuffs from the Nachukui Formation, Turkana Basin
No full text© 2025 Saini SamimThe Turkana Basin in northwest Kenya and southeast Ethiopia, hosted within the East African Rift System (EARS) is a renowned paleoanthropological region famous for the discoveries of several hominin species and their associated stone tool technologies. The Omo Group, a Plio-Pleistocene fossiliferous volcano-sedimentary succession, hosts these paleoanthropological remains which are intercalated with volcanic ash layers (tuffs) that provide critical age constraints for their enclosed artefacts. Establishing a robust tephrostratigraphic framework through 40Ar/39Ar geochronology and geochemical characterisation of volcanic products (pumice glass and their host tuff glass) is critical for refining the timeline of hominin milestone events. Key phases in hominin evolution are thought to have been influenced by variations in incoming solar radiation, with the most significant changes linked to precessional cycles (~21 kyrs). The ability to constrain the age estimates of important paleoanthropological sites and test hypotheses about potential links between environmental changes and hominin evolution are currently hampered by a) large uncertainties in the bracketing tuff age estimates (20,000 – 30,000 years; 2sigma) and b) similar major element geochemistry of tuffs which inhibits correct identification and leads to miscorrelation and age assignment. To address these issues, this study presents detailed single-grain, major and trace element geochemical analyses alongside high-precision 40Ar/39Ar geochronology on nine tuffs from the Nachukui Formation, West Turkana. The Nachukui Formation is a near-continuous volcano-sedimentary sequence which has yielded significant paleoanthropological discoveries such as the most complete Homo erectus skeleton, the Nariokotome Boy, the oldest examples of Acheulian tools (1.76 Ma) and the 3.3 Ma Lomekwian stone tool technologies. The presence of the datable temporal anchors (i.e., tuff layers) along with the potential of obtaining high-resolution paleoenvironmental records, make this region a prime locality for investigating key drivers of hominin evolution.
Accurate and precise identification of a given tuff layer is a crucial prerequisite for assigning ages to marker beds where datable material is otherwise absent. To this end, this work presents the novel application of LA-ICP-MS analyses to determine the trace element composition of volcanic glasses and pumice glass from the Turkana Basin at high-spatial resolution (10-20 microns). Volcanic glass shards and pumice glass exhibits morphological limitations (due to limited vertical thickness and the abundance of vesicles) which inhibits the application of a traditional ‘spot’ analysis approach and results in degraded precision and accuracy for natural tephra samples compared to internationally recognised reference materials. This study applied a ‘traverse’ approach which yields both high-precision (<5% RSDs) and accuracy (< +/-5% bias) in natural samples. These methodological advances permit the possibility of effectively creating trace element ‘fingerprints’ for tuffs in the region, including throughout the EARS.
To fully characterise a given tuff unit, a combined approach was employed which integrates two high-precision tephrochronological tools: a) major and trace element geochemical data and (b) high-precision single-grain 40Ar/39Ar geochronology. The combination of these techniques allowed the identification of distinct temporal and geochemical fingerprints for the previously indistinguishable Nariokotome tuffs. Overlapping age estimates among the Upper, Middle, and Lower Nariokotome tuffs, coupled with the similar major element geochemistry of the Upper and Middle Nariokotome tuffs, posed significant challenges for intra- and inter-basin correlation. By establishing robust geochemical and geochronological age estimates (uncertainties less than +/- 1.5 ka, 2sigma), this study improves the correlation of these units within the Turkana Basin, as well their potential correlations in the Konso Formation, Ethiopia and their potential source volcanoes in the central sector of the Main Ethiopian Rift.
While distinct temporal and geochemical signatures are crucial for identifying tuff units, in some instances, geochemical correlation alone remains challenging due to natural heterogeneities; for example, this study identified multiple compositional modes in three different units: the Middle Nariokotome, Morutot, and Orange tuffs. Major and trace element analysis revealed intra-pumice clast variability in the Morutot and Middle Nariokotome tuffs (two signatures) and inter-clast variability in the Orange Tuff (four signatures). In such cases, integrating geochronology with geochemistry resolved heterogeneous geochemical signatures and linked them to discrete volcanic eruptions. The geochemical signatures further provide insights into silicic magma dynamics, with intra-pumice variability in the Middle Nariokotome and Morutot tuffs reflecting magma mixing triggered by silicic recharge, while inter-clast variability in the Orange Tuff suggesting multiple melt bodies erupted in a short time interval.
A key application of the refined geochronology and geochemistry approached used in this study is refining the tephrostratigraphic context of important paleoanthropological sites. Since volcanic tuffs serve as crucial chronological anchors for terrestrial paleoenvironmental models in eastern Africa, the new age estimates for the Etirr and Ebei Tuffs (1,490.1 +/- 0.4 and 1,493.4 +/- 0.4 ka, respectively) from this study, resulted in a revision of an age-depth model for an important paleoenvironmental record associated with the Nariokotome Boy. The new age constraints suggest a clustering of volcanic activity around ~1500 ka, coinciding with evidence of high precipitation, increased vegetation fires, shifts in lake water chemistry, and abrupt changes in fossil phytolith preservation conditions. These findings indicate complex interactions between volcanism, paleoenvironmental shifts, and hominin ecosystems.
Through refining age estimates, enhancing tuff identification, and improving stratigraphic correlations, this study strengthens intra- and inter-basin correlations, advances the chronology of key paleoanthropological sites, provides new insights into silicic volcanic processes, and explores the potential links between recurrent volcanism, environmental changes, and hominin evolution in the Turkana Basin