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High-fidelity simultaneous measurements of velocity and temperature fluctuations using a dual-wire sensor within thermal boundary layers
No full textAbstract
A customised dual-wire sensor, incorporating both a cold-wire and a hot-wire, has been developed to enable simultaneous measurement of temperature and velocity at the same wall-normal location within a thermal boundary layer. This study details the sensor’s design, its in-situ calibration technique, and addresses potential sensor drift, offering guidance for its effective utilisation. While the results obtained from this sensor confirm the similarity between the wall-normal profiles for mean temperature and velocity, profiles of the temperature variance present a less obvious plateau in the logarithmic region when compared to the streamwise velocity variance. The simultaneously acquired instantaneous signals also reveal the markedly different characteristics of the streamwise velocity and temperature fluctuations at the edge of the boundary layer, highlighting the dissimilarity between velocity and temperature (with the latter exhibiting a unique one-sided distribution)
Detecting imbalanced financial markets through time-varying optimization and nonlinear functionals
No full textThis paper studies the time-varying structure of the equity market with respect to market capitalization. First, we analyze the distribution of the 100 largest companies’ market capitalizations over time, in terms of inequality, concentration at the top, and overall discrepancies in the distribution between different times. In the next section, we introduce a mathematical framework of linear and nonlinear functionals of time-varying portfolios. We apply this to study the market capitalization exposure and spread of optimal portfolios chosen by a Sharpe optimization procedure. These methods could be more widely used to study various measures of optimal portfolios and measure different aspects of market exposure while holding portfolios selected by an optimization routine that changes over time
The past, present and future for chronic ankle instability research: A bibliometric analysis from 1992 to 2023
No full textObjects To examine publication records between 1992 and 2023 for topics and trends in chronic ankle instability (CAI) research. Methods For CAI-related research papers published between 1992 and 2023 retrieved from the Web of Science Core Collection, bibliometric analysis via Citespace was undertaken on authorship cooperations, reference co-citations, and keyword co-occurrence. Results In total, 2697 research articles and reviews related to CAI were found. The journal “Journal of Athletic Training” contained the greatest number of relevant publications (6.3%). Jay Hertel, The University of North Carolina, and the USA were respectively the most prolific author (109), institution (122), and country (934). Nevertheless, after normalising publication volume by GDP per capita, China ranked highest with the largest CAI-related publication volume, with 0.041 per US dollar. Seven out of the top 10 most productive countries showed significant pivotal roles in the co-authorship network, with the USA having the highest betweenness centrality (0.69), whilst the BCs for both author or institutions were less than 0.1. “Delahunt E, 2010, Med Sci Sport Exerc, V42, P2106, DOI: 10.1249/MSS.0b013e3181de7a8a” was the paper that had the highest BC (0.26). The keyword “balance” occurred most frequently (424). The keyword co-occurrence network was able to be divided into five main subdomains (modularity=0.45), with the larges cluster #0 labelled “anterior talofibular ligament” (size=96, silhouette=0.816). Some keywords in the burstiness detection have drawn abruptly increased attention over the last five years, and reflect the frontiers of CAI research. They were; “prevalence”, “cross cultural adaption”, “management”, “gould procedure”, with burst strengths between 5.98 and 13.89. Conclusions CAI has drawn increasing research interest globally, yet high-quality, intervention-related studies remain scarce. USA-based authors and affiliations dominate both publication volume and academic influence. Shifts in research hotspots from structural to functional concerns are evident. Future directions include epidemiological investigations based on diverse cohorts and adopting currently-emerging diagnosis and treatment technologies
Generation and heterozygous repair of human iPSC lines from two individuals with the neurodevelopmental disorder, TRAPPC4 deficiency
No full textA rare neurodevelopmental disorder has been linked to a well-conserved splice site variant in the TRAPPC4 gene (c.454 + 3A > G), which causes mis-splicing of TRAPPC4 transcripts and reduced levels of TRAPPC4 protein. Patients present with severe progressive neurological symptoms including seizures, microcephaly, intellectual disability and facial dysmorphism. We have generated stem cells from fibroblasts of two individuals with the same homozygous TRAPPC4 c.454 + 3A > G pathogenic variant and used CRISPR/Cas9 editing to generate heterozygous gene-corrected isogenic controls. Clones were tested for pluripotency, differentiation potential, genotyped and karyotyped. These iPSC-based models will be used to understand disease mechanisms of TRAPPC4 disorder
The effect of a low-load plyometric intervention on running kinematics in youth with cerebral palsy: A randomised controlled trial
No full textBACKGROUND: For children and adolescents with cerebral palsy (CP) who are independently ambulant (Gross Motor Function Classification System (GMFCS) I or II), running is a fundamental movement skill that enables them to play and engage in school and community activities. A running intervention which resulted in good running goal attainment should logically have improved running kinematics, however, this has not yet been established. RESEARCH QUESTION: Does a low-load plyometric running intervention improve joint kinematics during running in children with CP? METHODS: Three-dimensional gait analysis was undertaken before and after a 12-week intervention. The Gait Profile Score (GPS) was calculated, and linear mixed models were developed. RESULTS: 36 children with cerebral palsy (control group: male=10, female=8, GMFCS I=12, GMFCS II=6, mean age=12.7 years; intervention group: male=13, female=5, GMFCS I=12, GMFCS II=6, mean age=12.7 years) were included in this study. No significant between-group differences in GPS were found at follow-up. The GPS increased (i.e. running kinematics became more atypical) as speed increased. SIGNIFICANCE: A low-load plyometric intervention which resulted in significant goal attainment in children with CP had no overall effect on running kinematics as measured by the GPS. Future studies should be powered according to both GMFCS level and distribution (unilateral vs bilateral CP)
Generation and characterisation of four human NAD(P)HX epimerase (NAXE) knockout iPSC lines
No full textPathogenic variants in NAD(P)HX epimerase (NAXE) cause early-onset progressive encephalopathy with brain edema and/or leukoencephalopathy-1 (PEBEL1), an ultra-rare severe neurometabolic disorder resulting in death in infancy. The absence of functional NAD(P)HX epimerase leads to accumulation of S- and R-forms of NAD(P)HX, inhibiting key metabolic pathways. We have generated four NAXE-deficient cell lines via simultaneous CRISPR/Cas9-mediated gene knockout (KO) of NAXE and episomal reprogramming of control human fibroblasts into induced pluripotent stem cells (iPSCs). We have demonstrated loss of NAXE gene expression, characterized iPSC pluripotency and differentiation potential into three germ layers. This provides a suitable model for investigating disease mechanisms and therapies
Playing with Paper Dolls: The evolution of cancer cytogenetics as a clinical laboratory science
No full text© 2025 Lynda Jane CampbellPlaying with Paper Dolls is an exploration of the development of the field of cancer cytogenetics, the chromosome analysis of cancer cells. It is part narrative history and part memoir as I spent most of my working life in the field. I used an oral history approach and interviewed over fifty cytogeneticists and others. Their words are quoted extensively.
Cancer cytogenetics started in a handful of laboratories in the 1950s. Its transition from obscure research interest to essential clinical laboratory test required several methodological and taxonomic inventions. The objects of study were always chromosomes but new ways of seeing those objects were needed, including the addition of fluorescent tags to probe the underlying genetic rearrangements. Each innovation prompted changes to the taxonomy so that workers around the world could understand and communicate with each other.
Cytogenetics developed in parallel with molecular biology and yet the two sciences had a difficult relationship. I describe the discovery and elucidation of three important chromosome abnormalities in various types of leukaemia and lymphoma to illustrate the reliance of both cytogenetics and molecular biology upon the other discipline. Each played an important role in establishing the underlying genetics of cancer.
Linking chromosome abnormalities to specific types of cancer was critical for establishing chromosome analysis as a clinical test. But also required were the multinational workshops and clinical trials that proved cytogenetics could assist with diagnosis and treatment of cancer patients. In the process, cytogeneticists needed to develop their specialty with the formation of societies, credentialling, specialist books and journals.
Cancer cytogenetics laboratories were always full of women, although initially only as technicians. I investigate the role of women in the development of the field and the relationships between the various actors in cytogenetics laboratories: pathologists, scientists and technologists. These interactions have been and remain problematic. And ultimately, I discuss the possible demise of the specialism as new methodologies arise with the potential to supersede cytogenetics in the diagnosis of cancer
Avian nest architecture: evolutionary drivers and thermal consequences
No full text© 2025 Silvia ColomboMany avian species lay eggs in nests to protect eggs and nestlings from external factors such as predators and climatic conditions. Nests are incredibly diverse, ranging from simple scrapes on the ground to complex structures. To date, the drivers behind this diversity remain poorly understood. For years, it has been suggested that nests offer protection from parasites, predators, and climatic factors. In this thesis, I explored the factors influencing the evolution of variation in nest traits and how these changes influence the nest microclimate. Moreover, I investigated whether species that build more complex nests — such as domed nests — that may require more energy and time to be built, are specialized to specific environments where their structure could provide benefits.
In my second chapter, I present observations based on a published database of nest architecture in birds and small literature review highlighting the previously neglected diversity in nest types within families, genera, and even species. In my third chapter, I performed a comparative analysis at an order level (passerines) to test whether domed nests evolved in both very hot (and arid) and cold environments. In this chapter, I also quantified the benefits that the roof in domed nests could offer in terms of thermal properties by comparing the nest internal temperature between open- and dome-nesting species in the same environment. In the fourth chapter, I investigated the role of climatic variables at a different scale, focusing on a family of birds called tanagers (Thraupidae); this study aimed at understanding if climatic variables influence the evolution of specific nest traits (such as the wall thickness, entrance diameter, nest depth) in both open and domed nests. Lastly, in my fifth chapter, I present a field experiment on Superb fairy-wren’s nest, to study whether the weather experienced by a bird before building its nest influences the nest traits. In the second part of this chapter, on the same nests, I explored if different nest traits affect nest internal microclimate and to what extent.
Overall, I have provided evidence in my dissertation that climatic factors have substantially contributed to the variation in nest architecture and traits between closely related species and within species. I have also shown that this variation can affect the nest microclimate, which could help mitigate the adverse effects of both extremely cold and hot temperatures
The stochastic behavior of electricity prices under scrutiny: Evidence from spot and futures markets
No full textThis article proposes a stochastic volatility jump–diffusion model for pricing electricity derivative contracts. The main objective is to develop a model that effectively captures the characteristics and stylized facts of the electricity spot market, such as mean reversion, changing expectations in the spot price’s long-run level, seasonality, extreme volatility, price spikes, and time-varying jump intensity. We employ a particle filter that relies on both spot prices and futures data to estimate model parameters. The results demonstrate that incorporating the aforementioned features is crucial for accurately fitting both spot and futures prices, as evidenced by data from the Australian electricity market
Investigating the effects of orexin receptor 1 antagonism on decision making under uncertainty
No full textOrexins/hypocretins are neuropeptides produced by several thousand neurons in the lateral hypothalamus. They project widely through the central nervous system where they release orexins which bind to two regionally selective G-protein coupled receptors: OX1R and OX2R. Orexins are well known as regulators of the sleep/wake cycle, however, recent investigations into orexinergic modulation of feeding and drug-seeking behaviour suggest they also play a role in reward processing and decision making. In the present study, we investigated the effects of OX1R antagonism on goal-directed decision making using an operant probabilistic reversal learning (PRL) task. 44 male C57/BL6 mice were dosed daily with an OX1R selective antagonist (1-SORA-51, 45 mg/kg) or vehicle (20 % w/v TPGS) while performing a PRL task consisting of 5 sessions on 5 consecutive days of probabilistic discrimination learning, followed by 5 sessions of reversal learning, both on and off drug, in a crossover design. Behaviours were then analysed within a reinforcement learning framework. Mice treated with 1-SORA-51 show a significant decrease in learning both initial and reversed reward contingencies, mediated largely through learning from positive outcomes. 1-SORA-51 also increased exploratory behaviours, both during learning and after reward contingencies had been learned. The findings suggest that OX1R signalling plays multiple roles in decision making in both learning and reward processing, largely by impacting the positive reward domain. As such, OX1R antagonists may be of therapeutic interest for improving abnormal reward processing and explore-exploit behaviours, such as the heightened sensitivity to drug cues and reduced responses to natural rewards, or heightened delay discounting as observed in people with substance use disorders