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For an arbitrary countable discrete infinite group G, non-singular rank-one actions are introduced. It is shown that the class of non-singular rank-one actions coincides with the class of non-singular $(C,F)$-actions. Given a decreasing sequence of cofinite subgroups in G with $\bigcap _{n=1}^\infty \bigcap _{g\in G}g\Gamma _ng^{-1}=\{1_G\}$, the projective limit of the homogeneous G-spaces $G/\Gamma _n$ as $n\to \infty $ is a G-space. Endowing this G-space with an ergodic non-singular non-atomic measure, we obtain a dynamical system which is called a non-singular odometer. Necessary and sufficient conditions are found for a rank-one non-singular G-action to have a finite factor and a non-singular odometer factor in terms of the underlying $(C,F)$-parameters. Similar conditions are also found for a rank-one non-singular G-action to be isomorphic to an odometer. Minimal Radon uniquely ergodic locally compact Cantor models are constructed for the non-singular rank-one extensions of odometers. Several concrete examples are constructed and several facts are proved that illustrate a sharp difference of the non-singular non-commutative case from the classical finite measure preserving one: odometer actions which are not of rank-one and factors of rank-one systems which are not of rank one; however, each probability preserving odometer is a factor of an infinite measure preserving rank-one system, etc.
This study investigates neuropsychological and psychosocial outcomes in patients with traumatic brain injury (TBI) and post-traumatic epilepsy (PTE) compared to a healthy control group.
Method:
Utilizing a quasi-experimental cross-sectional design, the research involved patients with TBI and PTE referred from a Taiwanese medical center. An age- and education-matched control group of healthy adults without traumatic injuries was also recruited. The study involved analyzing retrospective medical records and applying a comprehensive suite of neuropsychological tests and psychosocial questionnaires.
Results:
Executive function measures revealed significantly reduced performance in both the TBI and PTE groups compared to controls. Specifically, the MoCA scores were lowest in the PTE group, followed by the TBI group, and highest in the controls. Measures of subjective symptomatology showed comparably elevated levels in both the TBI and PTE groups relative to controls.
Conclusion:
The research suggests that PTE may intensify the difficulties faced by individuals with TBI, but its impact on overall recovery might not be significant, considering the trajectory of the brain injury itself. Notably, the MoCA results indicate that cognitive deficits are more pronounced in PTE patients compared to those with TBI, underscoring the necessity for targeted neuropsychological assessments. Further investigation is essential to explore PTE’s broader neuropsychological and psychosocial impacts. These findings advocate for tailored care strategies that address both neuropsychological and psychosocial needs, ensuring comprehensive management of TBI and PTE.
The Malabar dwarf puffer, Carinotetraodon travancoricus is the smallest known pufferfish (family Tetraodontidae) and one of the smallest freshwater fishes of the Indian subcontinent. Due to their miniature size, wacky behaviour and appearance, they are much preferred in the international aquarium fish trade, although little is known regarding their breeding activity in captivity and their embryonic development. The purpose of this study was to fill these knowledge gaps. Wild-caught Malabar dwarf puffers were acclimatised to conditions, and pairs were introduced to breeding tanks. Adult fishes were fed with live and frozen diets including Artemia nauplii, moina and bloodworm. During spawning seasons, adult fish displayed elaborate courtship behaviour around sunset. Carinotetraodon travancoricus is a batch spawner releasing 1 to 5 eggs per diem. The eggs were spherical, and non-sticky, with a diameter of 1.48 ± 0.1 mm, and hatching took place after 108 to 116 h post-incubation. The newly hatched larvae were 3.5 ± 0.2 mm in length, and weighed 2.9 ± 0.4 mg. The early larvae have substantial yolk and oil globules as an energy reserve. Histological studies on mature females suggested the batch spawning nature of the species and low fecundity. Given its unique reproductive behaviour and characters, in situ protected habitats are required to ensure their continued survival in the wild, apart from encouraging captive breeding to augment the demand in the international aquarium fish trade.
In 2020, Asian Americans were the least descriptively represented at all levels of elected office compared to whites, Blacks, and Latinos (Sedique, Bhojwani, and Lee 2020). In this context, Asian women lagged behind Asian men in holding local-level positions, yet they surpassed Asian men in holding federal and statewide offices, and they led 81% of state- and local-level Asian civil rights organizations (AAPI Power Fund 2020; Reflective Democracy Campaign 2021). Do gender disparities in Asian American political representation arise because Asian women are less likely to run for office than Asian men, or because they are less likely to win elections? Do these disparities vary across levels of office? And are they unique to Asian Americans?
Determine whether weight gain velocity (g/day) 30 days after initiating feeds following cardiac surgery and other clinical outcomes improve in infants with single-ventricle physiology fed an exclusive human milk (EHM) diet with early fortification compared to non-protocolised “standard of care.”
Methods:
This retrospective cohort study compares term infants with single-ventricle physiology who underwent neonatal surgical palliation. The retrospective control group (RCG) was fed according to non-protocolised standard of care at a single centre and was compared with infants in a previous protocolised multi-site randomised controlled trial assigned to either an EHM group or a control group (TCG). The primary outcome measure is weight gain velocity. Secondary outcomes include change in weight z-score, and incidence of feeding intolerance and necrotising enterocolitis.
Results:
We evaluated 45 surgically palliated neonates with single-ventricle physiology compared to the prior trial patients (EHM = 55, TCG = 52). Baseline demographics were similar between groups, except the RCG had fewer patients with hypoplastic left heart syndrome (51% vs. 77% vs. 84%, p = 0.0009). The RCG grew similarly to the TCG (7.5 g/day vs. 8.2 g/day), and both groups had significantly lower growth than the EHM group (12 g/day). Necrotising enterocolitis/suspected necrotising enterocolitis were similar in the RCG versus TCG but significantly higher in the RCG compared to the EHM group (20.5% vs. 3.6%, p = 0.033). Incidences of other morbidities were similar.
Conclusions:
Neonates with single-ventricle physiology have improved short-term growth and decreased risk of necrotising enterocolitis or suspected necrotising enterocolitis when receiving an EHM diet after surgical palliation compared to non-protocolised feeding with bovine formula.
This article re-examines the traditional account of administrative decision-making under wide conferrals of statutory power. The received wisdom in such cases is that public officials exercise “discretion”, usually defined as freedom of choice. Based on a doctrinal study of the English planning system and related case law, this paper contends that the notion of discretion as choice obscures one of the defining characteristics of modern government. That is, the making of public decisions tackling practical problems with intelligent and expert judgement under legal standards set out in legislation and further developed by the courts. More widely, the paper discusses the foundational role of tacit knowledge and decision-making expertise in public administration.
Coronary anomalies occur in 0.2% to 1.2% of the population, with the anomalous aortic origin of the coronary arteries accounting for one third of these cases. Clinical presentations can vary from asymptomatic to experiencing cardiac symptoms and sudden death, making diagnosis challenging. In this report, we present a novel artificial intelligence-supervised vectorcardiographic analysis and the subsequent successful surgical treatment of a young patient.
The Duke Activity Status Index is used to assess an individual patient’s perception of their fitness abilities. It has been validated and shown to predict actual fitness in adults but has been studied less in the paediatric population, specifically those with heart disease. This study aims to assess if the Duke Activity Status Index is associated with measured markers of physical fitness in adolescents and young adults with heart disease.
Methods:
This retrospective single-centre cohort study includes patients who completed a minimum of 12 weeks of cardiac rehabilitation between 2016 and 2022. Cardiac rehabilitation outcomes included physical, performance, and psychosocial measures. A comparison between serial testing was performed using a paired t-test. Univariable and multivariable analyses for Duke Activity Status Index were performed. Data are reported as median [interquartile range].
Results:
Of the 118 participants (20 years-old [13.9–22.5], 53% male), 33 (28%) completed at least 12 weeks of cardiac rehabilitation. Median peak oxygen consumption was 60.1% predicted [49–72.8%], and Duke Activity Status Index was 32.6 [21.5–48.8]. On Pearson’s correlation assessing the Duke Activity Status Index, there were significant associations with % predicted peak oxygen consumption (r = 0.49, p < 0.0001), 6-minute walk distance (r = 0.45, p < 0.0001), Duke Activity Status Index metabolic equivalents (r = 0.45, p < 0.0001), and dominant hand grip (r = 0.48, p < 0.0001). In multivariable analysis, the % predicted peak oxygen consumption (r = 0.40, p = 0.005) and dominant hand grip (r = 0.37, p = 0.005) remained statistically significant.
Conclusions:
Duke Activity Status Index is associated with measures of physical fitness in paediatric and young adults with heart disease who complete a cardiac rehabilitation program.
Anthropogenic-mediated climate change is expected to negatively affect pest management in agriculture. Hence, we investigated the oviposition, immature mortality, and developmental processes of Spodoptera species (Spodoptera exigua (Hübner) and Spodoptera litura (Fabricius)) under different temperatures (20, 25, and 30°C) and relative humidity (RH) (30–35, 50–55, 70–75, and 90–95%) conditions. For fecundity, mouths of each Spodoptera species were released into a rectangular box whose inner walls were covered with a sheet of white paper for each combination of temperature and RH. The mouths were kept inside the box to deposit eggs for 72 h. Temperature and RH significantly affected the fecundity, with the maximum number of eggs laid in 70–75% at 30°C. The highest egg and larval mortalities were recorded in 30–35 and 90–95% RH, respectively. Temperature and RH greatly affected the developmental period (egg–adult) and adult emergence rate. The rapid development was recorded in 70–75% RH at 30°C. Higher number of adults was found with an increase in temperature and RH. Adult longevity was significantly higher in 70–75% RH at 20°C. Based on the present study's findings, temperature and RH had an individual apparent effect on the developmental processes of Spodoptera species instead of an interactive effect. Therefore, there is need for an in-depth study of the influence of several climatic factors, including CO2, on the developmental modality and demographic changes of Spodoptera species to assess the impacts of climatic components and the sustainable development of management strategies.
The study analysed 93 samples from four Serbian clay deposits to determine their suitability for ceramics production. The samples were mainly composed of illite and kaolinite. Ternary diagrams were used to classify the samples and evaluate their applicability. Winkler's diagrams, ternary graphs and mineralogical compositions were analysed. The results showed a broader area in these graphs than previously determined for structural ceramics, as well as the potential of these clays for ceramic production. The study used dry-milled, hydraulically semi-dry, pressed and fired samples to assess water absorption and flexural strength and statistical analysis to determine the key parameters influencing final product quality, including that of refractory, wall and floor tiles. This paper evaluates the raw clay materials’ applicability in ceramic production, promoting sustainable use through rapid initial tests, energy savings through dry milling and ecologically sound principles through resource-efficient evaluation.
Venovenous collaterals are abnormal connections between the systemic and pulmonary venous systems. They are commonly seen in the Fontan circulation and may lead to significant hypoxaemia. Transcatheter closure of venovenous collaterals is a potential but controversial treatment as the long-term benefits and outcomes are not well understood.
Methods:
This retrospective cohort study utilised data from the Australian and New Zealand Fontan Registry. Patients who underwent transcatheter venovenous collateral occlusion for hypoxemia from the year 2000 onwards were included. Atriopulmonary and Kawashima-type Fontan circulations were excluded to reflect a more contemporary Fontan cohort.
Results:
Nineteen patients (age 19.3 ± 7.8 years, 53% female) underwent transcatheter venovenous collateral occlusion. Compared to baseline, mean oxygen saturation was improved at latest follow-up (90.5% vs 87.0%; p = 0.003). Nine patients achieved a clinically significant response (defined as an increase of at least 5% to 90% or greater), and this was associated with lower baseline Fontan pressures (12.9 v 15.6 mmHg; p = 0.02). No heart failure hospitalisations, arrhythmia, transplant referrals, or mortality were observed during the median follow-up period of 4 years. Two patients experienced thromboembolic events and five patients underwent re-intervention.
Conclusion:
Transcatheter occlusion of venovenous collaterals in Fontan patients with chronic hypoxaemia resulted in a modest increase in oxygenation over a median follow-up of 4 years and longer-term prognosis did not appear to be adversely affected. Lower Fontan pressures at baseline were associated with a greater improvement in oxygenation.
Elastoinertial turbulence (EIT) is a chaotic flow resulting from the interplay between inertia and viscoelasticity in wall-bounded shear flows. Understanding EIT is important because it is thought to set a limit on the effectiveness of turbulent drag reduction in polymer solutions. Here, we analyse simulations of two-dimensional EIT in channel flow using spectral proper orthogonal decomposition (SPOD), discovering a family of travelling wave structures that capture the sheetlike stress fluctuations that characterise EIT. The frequency-dependence of the leading SPOD mode contains distinct peaks and the mode structures corresponding to these peaks exhibit well-defined travelling structures. The structure of the dominant travelling mode exhibits shift–reflect symmetry similar to the viscoelasticity-modified Tollmien–Schlichting (TS) wave, where the velocity fluctuation in the travelling mode is characterised by large-scale regular structures spanning the channel and the polymer stress field is characterised by thin, inclined sheets of high polymer stress localised at the critical layers near the channel walls. The travelling structures corresponding to the higher-frequency modes have a very similar structure, but are nested in a region roughly bounded by the critical layer positions of the next-lower-frequency mode. A simple theory based on the idea that the critical layers of mode $\kappa$ form the ‘walls’ for the structure of mode $\kappa +1$ yields quantitative agreement with the observed wave speeds and critical layer positions, indicating self-similarity between the structures. The physical idea behind this theory is that the sheetlike localised stress fluctuations in the critical layer prevent velocity fluctuations from penetrating them.
Instability and rupture dynamics of a liquid nano-thread, subjected to external hydrodynamic perturbations, are captured by a stochastic lubrication equation (SLE) incorporating thermal fluctuations via Gaussian white noise. Linear instability analysis of the SLE is conducted to derive the spectra and distribution functions of thermal capillary waves influenced by external perturbations and thermal fluctuations. The SLE is also solved numerically using a second-order finite difference method with a correlated noise model. Both theoretical and numerical solutions, validated through molecular dynamics, indicate that surface tension forces due to specific external perturbations overcome the random effects of thermal fluctuations, determining both the thermal capillary waves and the evolution of perturbation growth. The results also show two distinct regimes: (i) the hydrodynamic regime, where external perturbations dominate, leading to uniform ruptures, and (ii) the thermal-fluctuation regime, where external perturbations are surpassed by thermal fluctuations, resulting in non-uniform ruptures. The transition between these regimes, modelled by a criterion developed from linear instability theory, exhibits a strong dependence on the amplitudes and wavenumbers of the external perturbations.
We study actions of higher rank lattices $\Gamma <G$ on hyperbolic spaces and we show that all such actions satisfying mild properties come from the rank-one factors of G. In particular, all non-elementary isometric actions on an unbounded hyperbolic space are of this type.
The UK welfare landscape is increasingly challenging due to ongoing austerity involving public sector cuts, service retrenchment, and withdrawal of statutory responsibilities. This article shows that as the welfare state contracts, precarity increases and responsibility for service provision is progressively devolved to front-line individuals and service users. To illustrate, the article examines the use of assistive and everyday technologies to improve social housing residents’ quality of life based on a longitudinal mixed methods study conducted between 2020 and 2022. The findings highlight how housing providers can support person-led technology interventions for older residents, where minor improvements positively impact day-to-day living. However, interventions are often limited by practicalities, capacity, and cost. This article connects technological engagement in housing to the ongoing ‘responsibilisation’ of many areas of housing provision to social landlords and tenants. This suggests an extension of responsibility where social housing providers are papering over the cracks in the welfare state.