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The association between fibrotic diseases and treatment resistant hypertension in England
No full textAims
Multimorbidity has been identified as a research priority in recent years; fibrosis (progressive organ scarring) is one mechanism that may underpin multimorbidity. Some studies suggest hypertension could be fibrotic, particularly severe hypertension (uncontrollable with medications); however, it is not currently known whether severe hypertension is associated with fibrotic conditions. The objective is to investigate whether treatment-resistant hypertension is associated with fibrotic conditions.
Methods and results
We used the Clinical Practice Research Datalink Aurum primary care database to define a cohort of people with hypertension during 2015. We determined the percentage of people who had conditions with fibrotic manifestations and explored differences respective to hypertension control. We applied multivariable logistic regression to analyse associations (P < 0.001) between hypertension control and each fibrotic condition, respectively. Of 1 340 495 people with hypertension during 2015, 83.50% (n = 1 119 333) had managed hypertension either by lifestyle or by medication; 16.50% (n = 221 162) had treatment-resistant hypertension. Fibrotic conditions were more common {75.40% [95% confidence interval (CI): 75.20–75.60] vs. 68.90% (95% CI: 68.81–70.01)} in people with treatment-resistant hypertension compared with those with managed hypertension. We found that treatment-resistant hypertension was associated with cardiomyopathy (ORadj: 1.85, 95% CI: 1.81–1.90), both Type 1 and Type 2 diabetes (ORadj: 1.49, 95% CI: 1.44–1.55, ORadj: 1.61, 95% CI: 1.60–1.63, respectively), liver fibrosis (ORadj: 1.52, 95% CI: 1.46–1.58), valve fibrosis (ORadj: 1.41, 95% CI: 1.37–1.44), and urinary fibrosis (ORadj: 1.41, 95% CI: 1.36–1.47).
Conclusion
The proportion of people with fibrotic conditions was greater in those with treatment-resistant hypertension than managed hypertension. The identified associations between treatment-resistant hypertension and fibrotic conditions may point to common disease pathways, which should be further explored to understand shared mechanisms
AQUA-SLAM: tightly-coupled underwater acoustic-visual-Inertial SLAM with sensor calibration
No full textUnderwater environments pose significant challenges for visual simultaneous localization and mapping (SLAM) systems due to limited visibility, inadequate illumination, and sporadic loss of structural features in images. Addressing these challenges, this article introduces a novel, tightly coupled acoustic-visual-inertial SLAM approach, termed AQUA-SLAM, to fuse a Doppler velocity log (DVL), a stereo camera, and an inertial measurement unit (IMU) within a graph optimization framework. Moreover, we propose an efficient sensor calibration technique, encompassing the multisensor extrinsic calibration (among the DVL, camera, and IMU) and the DVL transducer misalignment calibration, with a fast linear approximation procedure for real-time online execution. The proposed methods are extensively evaluated in a tank environment with ground truth, and validated for offshore applications in the North Sea. The results demonstrate that our method surpasses current state-of-the-art underwater and visual-inertial SLAM systems in terms of localization accuracy and robustness. The proposed system will be made open-source for the community
Self-initiated humour protocol: a pilot study with an AI agent
No full textIntroduction: Non-hostile humour and laughter have been known for therapeutic benefits in an individual’s mental health and wellbeing. To this end, we evaluated the Self-Initiated Humour Protocol (SIHP), a new type of self-administrable laughter intervention that utilises spontaneous and self-induced laughter. Rooted in the core principles of the Self-Attachment Technique—in which an individual creates an affectional bond with their childhood self as represented by their childhood photo or personalised childhood avatar—SIHP provides an algorithmic framework for individuals to learn to laugh in a non-hostile manner and develop a sense of humour in all possible life contexts. This allows SIHP to be self-administered by interacting with an AI agent.
Methods: An 8-week intervention was conducted with N = 27 adult participants. Exclusion criteria: severe depression or anxiety (PHQ-9 and GAD-7 scores above 15). Participants’ measurements were collected in the areas of wellbeing, use of different humour styles, emotional self-regulation, self-compassion and psychological capital, and analysed to understand any changes over time. Measurements were taken immediately before, after the intervention, and at the 3-month follow-up. Throughout the intervention, participants were required to practise SIHP 20 min a day with the aid of an emotionally intelligent chatbot and their personalised child avatar in virtual reality (VR).
Results: Analysis of results at the 3-month follow-up showed significant improvements in the primary outcome of wellbeing with large effect size (
r
=
0.92
), as well as a range of secondary outcomes with large effect sizes, self-compassion (
r
=
0.93
), use of self-enhancing humour (
d
=
0.80
), and emotion regulation (
d
=
0.87
); the results also showed improvement to participant’s psychological capital with moderate effect size (
d
=
0.56
).
Discussion: This study shows the potential for the practice of SIHP as supported by an emotionally intelligent chatbot and personalised child avatar to have medium-term positive effects, which should be validated through future randomised trials
Computational modelling of water-fuelled Hall Effect Thrusters
No full textThis paper presents a Particle-In-Cell code designed for the simulation of water-fuelled
Hall Efect Thrusters, including two diferent propellants: water vapour and oxygen
(the latter being intended for water electrolysis propulsion with oxygen supplied
through the anode and hydrogen through the cathode). The reactive model is struc‑
tured in two stages, encompassing not only the initial reactions of water vapour
and oxygen molecules (1st stage) but also the reactions of the diatomic and mono‑
atomic products resulting from them (2nd stage). Specifcally, the model accounts
for 45 reactions in the case of water vapour and 18 reactions in the case of oxygen,
including the most relevant excitation events for each species. The Particle-In-Cell
code uses a combination of a 0-dimensional model with a 2-dimensional model.
The 0-dimensional model provides initial neutral and electron densities, as well
as the most signifcant reactions, to facilitate the convergence of the 2-dimensional
model without the computational burden of starting a simulation from scratch. The
0-dimensional model reveals that the reactions considered within the 2nd stage are
crucial for the plasma species composition of the discharge. The oxygen plasmas
consist mainly of O+ and O+
2 ions in a similar proportion, while double and negative
ions do not play a signifcant role. Neutrals (O2 and O) also show similar distributions,
depending on the thruster’s operating conditions. Water vapour plasmas are domi‑
nated by OH+, H2O+, H+, and O+ ions, with other species such as H+
2 , O++, and nega‑
tive ions being negligible. The neutral population is predominantly composed of mon‑
oatomic H particles. The 0-dimensional model also demonstrates that all ionisation
fractions of the species follow an exponentially increasing trend with the electron tem‑
perature. Finally, the 2-dimensional model provides additional insight into the plasma
evolution, electron temperature, power losses coming from the reactive model
and equilibrium points of the system
Portable molecular diagnostic platform for rapid point-of-care detection of mpox and other diseases
No full textThe World Health Organization’s designation of mpox as a public health emergency of international concern in August 2024 underscores the urgent need for effective diagnostic solutions to combat this escalating threat. The rapid global spread of clade II mpox, coupled with the sustained human-to-human transmission of the more virulent clade I mpox in the Democratic Republic of Congo, highlights a critical gap in point-of-care diagnostics for this emergent disease. In response, we developed Dragonfly, a portable molecular diagnostic platform for point-of-care use that integrates power-free nucleic acid extraction (<5 minutes) with lyophilised colourimetric LAMP chemistry. The platform demonstrated an analytical limit-of-detection of 100 genome copies per reaction for monkeypox virus, effectively distinguishing it from other orthopoxviruses, herpes simplex virus, and varicella-zoster virus. Clinical validation on 164 samples, including 51 mpox-positive cases, yielded 96.1% sensitivity and 100% specificity for orthopoxviruses, and 94.1% sensitivity and 100% specificity for monkeypox virus. Here, we present a rapid, accessible, and robust point-of-care diagnostic solution for mpox, suitable for both low- and high-resource settings, addressing the global resurgence of orthopoxviruses in the context of declining smallpox immunity
IT-enabled organisational transformation and green employment growth in microfirms
No full textIn this paper, we explore whether IT-enabled organisational transformation (ITOT) moderates the relationship between eco-innovation and the growth performance of microfirms. Our framework conceptualises ITOT in microfirms as a multistage process that includes: (i) setting a digitalisation strategy, (ii) adopting advanced information systems technology (IST) artefacts and (iii) developing in-house digital resources and capabilities. The analysis of a sample of 5015 microfirms from 39 countries indicates that eco-innovations boost firm growth when coupled with (i) a formalised digitalisation strategy, (ii) adoption of advanced IST artefacts (e.g., digital technologies that characterise Industry 4.0) and (iii) digital resources and capabilities in microfirms. These findings contribute to the growing digitalisation literature by highlighting the essential role that ITOT processes play in enabling sustainability-led growth pathways for microfirms. The paper advocates for the viability and performance benefits of a twin digital and ecological transformation and showcases the potential of ITOT for an economically successful net-zero transition that embraces microfirms
Joint-velocity-scalar probability density function method for modelling high-speed turbulent combustion
No full textThis thesis presents a joint-velocity-scalar probability density function (VSPDF) model aimed at improving dual-mode ramjet engine simulations. This model stands out as a unified closure for sub-grid turbulence interactions in large eddy simulations (LES), requiring minimal coefficients and making no assumptions about specific flame structure or combustion regime. The VSPDF is transported using a conservative and thermodynamically consistent stochastic fields (SF) formulation, ensuring stability in shocked turbulent flows. The Eulerian nature of SF allows direct implementation of a high-order numerical scheme and adaptive mesh refinement (AMR). Various cases showcase the model’s unique capabilities, such as the ability to distinguish between laminar shear and turbulence, and to capture extreme events such as autoignition.
Two improvements to the model are proposed. The first uses a tensor-based neural network to replace existing sub-grid mixing model. By respecting physical symmetries and dimensional consistency, this approach outperforms both the original simplified Langevin model and a conventional neural network.
The second improvement targets the computational cost for resolving boundary layers by integrating an ODE-based wall model with the SF, producing accurate wall fluxes with 10 to 50 times coarser grids. A coupling procedure is proposed to maintain stability and ensure correct sub-grid fluctuation profiles. Simulations of a supersonic channel agree well with direct numerical simulations, showing significant improvement over LES without a wall model.
Finally, the wall-modelled SF is applied to simulate a dual-mode ramjet engine. The method shows good agreement with experimental results in terms of shock train length, pressure profile, and flame position, in two fundamentally different conditions. This demonstrates the model's wide applicability, allowing for confident use in the design and optimisation of ramjet and scramjet engines.
This study represents the first application of VSPDF in simulating ramjet engines, as well as the first solver to integrate SF, AMR, and wall modelling.Open Acces
Contrail observation limitations using geostationary satellites
No full textContrails are a significant contributor to aviation's climate impact with an effective radiative forcing similar to that from aviation's CO₂ emissions, yet large uncertainties remain. Many observational contrail studies rely on data from a single sensor, in recent years increasingly from a geostationary imager, accepting lower spatial resolution in exchange for higher temporal and spatial coverage. However, the ability of geostationary imagery to resolve contrails has not been systematically characterized. By comparing higher spatial resolution low Earth orbit satellite imagery from Visual Infrared Imaging Radiometer Suite (VIIRS) to geostationary satellite imagery from GOES ABI, we show that the latter does not resolve 80% of the contrails nor half of the total length compared to contrails identified with VIIRS. Our findings underscore the need for multi-sensor approaches to collect observational contrail data for improved validation of climate models and to enable more rigorous and verifiable contrail avoidance strategies
Phase behaviour of asymmetric mixtures for the net zero transition
No full textUnderstanding the thermophysical properties of fluids is crucial to the effective development of industrial processes and is dependent on models optimised against reliable experimental data that are always in short supply. Veridical since antiquity, the accelerating impact of climate change and unsustainable processes have promoted it to a problem of the utmost importance and urgency. The transition towards sustainability and net zero greenhouse gas emissions requires the resolution of many known unknowns and the dissolution of unknown unknowns. Of especial significance is the behaviour of the consistently asymmetric mixtures formed by carbon dioxide (CO2) and hydrogen (H2). This work provides some essential fragments of the information required; investigating the phase behaviour of mixtures of carbon dioxide with methanol and with isobutane, and of hydrogen with isobutane, alongside the behaviour of hydrogen mixtures more broadly. Low uncertainty experimental measurements have extended the range of available data and have been applied to optimise and assess thermodynamic models suitable for use in process design and simulation. A methodology by which such measurements may be conducted has been developed to allow for unprecedented levels of automation, necessary to address knowledge gaps with sufficient haste. The possibility of apparatuses capable of autonomously exploring entire phase spaces, including self-calibration and some density measurement, has been demonstrated.Open Acces