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A noise-resistant and annotation-free supervoxel-based algorithm for rapid segmentation of multiphase X-ray images
No full textThis study introduces a three-dimensional supervoxel segmentation method to accurately separate solid and fluid phases in X-ray images of porous materials, with applications in energy research. Compared with intelligent segmentation algorithms requiring model training, the proposed method operates as a ready-to-use solution with significantly enhanced efficiency. When benchmarked against conventional approaches such as watershed transformation, our technique demonstrates superior segmentation accuracy. Tested on porous rock and gas diffusion layers under varying wettability, it accurately quantifies fluid saturation, interfacial area, curvature, and contact angles—key parameters for enhanced oil recovery, CO2 storage, and hydrogen fuel cells. The proposed three-dimensional segmentation method is noise-resistant and annotation-free, improving both the accuracy and efficiency of segmenting diverse micro-structural material datasets and providing reliable measurements of their geometric characteristics
Weaning patients off long-term prednisolone: a survey of physicians’ practice in the UK and Southeast Asia
No full textStudy Objective
Prolonged glucocorticoid (GC) use is associated with significant morbidity and mortality, including the development of glucocorticoid induced adrenal insufficiency. Recent guidance from the European Society of Endocrinology (ESE) and Endocrine Society (ES) provides a framework for tapering GCs. However, there is limited understanding into current practice across endocrine and other medical specialties, including barriers and challenges to GC weaning. This study aimed to establish how GCs are weaned in patients across endocrine and non-endocrine specialists.
Design and Setting
Anonymous online surveys were disseminated to all members of the Society for Endocrinology (SfE) and all members of the ASEAN (Association of Southeast Asian Nations) Federation of Endocrine Societies (AFES) and the Endocrine and Metabolic Society of Singapore (EMSS). Non-endocrine specialists were surveyed in the UK and in Singapore.
Results
A total of 306 (258 endocrine specialists and 48 non-endocrine specialists) responded to the survey. Approaches to discontinuing prednisolone were heterogeneous. Amongst endocrine respondents, only 78% would fully wean the prednisolone, with 50.4% switching to hydrocortisone to wean and 12.6% favouring long-term GC replacement without further investigations. Amongst the non-endocrine respondents, 16.7% would stop prednisolone abruptly and 10.4% would refer to endocrinology to supervise weaning. The most common barrier to weaning GCs reported by both endocrine and non-endocrine specialists was relapse of the underlying condition (55.9% and 70.8% respectively).
Conclusion
Relapse of the underlying condition is common, and endocrinology input may not be appropriate when this occurs. There remains a need to develop an evidence-based approach for safe and effective GC weaning and hypothalamic-pituitary-adrenal axis assessment.
Strengths and limitations of this study:
• A web-based survey capturing GC weaning practices amongst endocrine and non-endocrine specialists in the UK and Southeast Asia.
• Limitations include the respondent time frame of three months and design of the survey in English, which may have limited participation.
• The design of the survey relied on self-reported data, which may be subject to recall bias.
• The survey explores real-world barriers to GC weaning, which will inform the design of larger prospective GC weaning studies
Optimal number-conserved linear encoding for practical fermionic simulation
No full textNumber-conserved subspace encoding reduces resources needed for quantum simulations, but scalable com plexity trade-off bounds for M modes and N particles with O(N log M) qubits have remained unknown. We study
qubit-gate-measurement trade-offs through the lens of classical/quantum error correction complexity and develop
a framework of fermionic gate and measurement complexity based on classical encoder/decoder appearing in
the error correction framework. We demonstrate optimal encoding with random classical parity check code and
propose the Fermionic Expectation Decoder for scalable probability decoding in O(M4 ) bases. The protocol is
tested with variational quantum eigensolver on LiH in the STO-3G and 6-31G bases, and H2 potential energy
curve in the 6-311G* basis
Heat transfer improvement of tubular heat exchangers with twisted nail wire inserts
No full textMeeting the challenge of designing compact, energy-efficient, and sustainable heat exchangers requires inno vative yet practical passive heat transfer improvement techniques. This study introduces a new passive technique using innovative twisted nail wire inserts (TNWIs) in double-tube heat exchangers (DTHXs). Experiments are conducted under turbulent flow conditions (Reynolds number of 5000–21,250) with constant inlet temperatures of hot- and cold-water streams. Three distinct TNWI configurations − aligned, cross, and alternating nail arrangements − were tested at fixed nail spacing (P) to evaluate thermal-hydraulic performance and entropy generation, using a plain-tube DTHX as the baseline. Among these, the alternating configuration yields the best performance, achieving a 1.78-times higher Nusselt number (Nu), a maximum thermal performance factor (TPF) of 1.75, and the lowest entropy generation ratio (EGR), while requiring minimal material and maintaining low friction losses. Further evaluation with varying nail density ratios (L/P = 60, 30, and 20; L is the insert length) reveals that increased nail density enhances heat transfer (up to 2.29 times Nu enhancement) and reduces EGR (down to 2.15). New empirical correlations are developed for Nu, friction factor, and TPF, with prediction errors within ±10%. Compared to conventional inserts, TNWIs offer a simpler and energy-efficient alternative for advanced thermal system applications
Functional analyses and integrated mechanisms of cellular destruction by L-amino acid oxidase
No full textSnakebite accidents are prevalent worldwide and cause a spectrum of severe clinical manifestations and result in a reduction of patient quality of life and economic income. A major bottleneck in envenomation treatment is our limited understanding of how venom toxins perturb specific cellular processes involved in tissue necrosis. Here, we address this knowledge gap and define the cellular mechanisms via which cell death is triggered by the snake toxin L-amino acid oxidase (LAAO). LAAO is a highly toxic enzyme present in various venoms that causes tissue necrosis, edema, coagulopathies, and organ failure. Here, we identify the residues essential for LAAO oxidation and obtain a catalytically inactive LAAO mutant, which is unable to reproduce the cellular phenotypes. Striking cellular defects are triggered by a catalysis-dependent increase in oxidative stress, via H2O2 (reaction by product). LAAO uptake by cells leads to a decrease in lysosome number and size and inhibits autophagy flux. In parallel, mitochondria function is impaired by severe proton leakage, and mitochondrial fission is stimulated, causing their engulfment by autophagosomes. However, mitochondrial clearance is prevented by the lysosomal defects. The concurrent shutdown of cell respiration and energy consumption indicates that LAAO catalysis reduces both metabolism and cell fitness. Thus, essential organelles are coordinately impaired by LAAO activity, accelerating cell demise. Considering the multi-organelle impairment, strategies to reduce organelle injury after LAAO exposure may be effective to maintain critical cell functions and strengthen adaptive responses against cytotoxicity
Switching patients with congenital adrenal hyperplasia to modified-release hydrocortisone capsules: relative bioavailability and disease control
No full textBackground
Replacement therapy with modified-release hydrocortisone capsules (MRHC) restores the physiological circadian cortisol rhythm in congenital adrenal hyperplasia (CAH).
Aims
To determine the relative bioavailability of MRHC and evaluate an optimal protocol to switch CAH patients from standard therapy to MRHC.
Methods
(1): Crossover study in healthy participants comparing relative bioavailability of MRHC with immediate-release hydrocortisone (IRHC). (2): Post hoc analysis of first 4 weeks of phase 3 MRHC study when CAH patients were switched to MRHC.
Results
Twenty-four healthy male participants completed the relative bioavailability study: 20 mg MRHC showed comparable bioavailability to 20 mg IRHC tablets; mean AUC0−inf was 2650 versus 2450 h*nmol/L, ratio of 108% (90% confidence interval (CI) 103%−113%). In the phase 3 study, 122 CAH patients were recruited of which 63 patients were managed with IRHC alone at baseline; 31 of 63 were randomised to continue IRHC and 32 of 63 were randomised to switch to MRHC on the same daily dose but given twice daily. At 4 weeks, a greater reduction in both the 09:00 h 17-hydroxyprogesterone and androstenedione was observed in the MRHC group compared to the IRHC group; p < 0.001 and p = 0.01, respectively.
Conclusions
MRHC showed comparable bioavailability to IRHC based on cortisol AUC after 20 mg administration. Switching patients treated with IRHC to a twice daily MRHC regimen on the same daily dose (giving approximately two thirds of the dose at night) is an effective protocol for starting MRHC treatment
On the effects of parameters on galaxy properties in CAMELS and the predictability of Ωm
No full textRecent analyses of cosmological hydrodynamic simulations from CAMELS have shown that machine learning models can predict the parameter describing the total matter content of the universe, Ωm, from the features of a single galaxy. We investigate the statistical properties of two of these simulation suites, IllustrisTNG and ASTRID, confirming that Ωm induces a strong displacement on the distribution of galaxy features. We also observe that most other parameters have little to no effect on the distribution, except for the stellar-feedback parameter ASN1, which introduces some near-degeneracies that can be broken with specific features. These two properties explain the predictability of Ωm. We use optimal transport to further measure the effect of parameters on the distribution of galaxy properties, which is found to be consistent with physical expectations. However, we observe discrepancies between the two simulation suites, both in the effect of Ωm on the galaxy properties and in the distributions themselves at identical parameter values. Thus, although Ωm’s signature can be easily detected within a given simulation suite using just a single galaxy, applying this result to real observational data may prove significantly more challenging
Pore-scale imaging to quantify the evolution and reduction in trapped Co₂ due to Ostwald ripening
No full textGeological carbon storage is a key strategy for mitigating climate change, but the long-term stability of trapped CO2 remains uncertain. Transport of dissolved CO2 in the aqueous phase can cause the rearrangement of capillary-trapped CO2 in the pore space, which is called Ostwald ripening. Using high-resolution three-dimensional X-ray imaging, we visualized the in situ evolution of CO2 ganglia in reservoir sandstone during storage and quantified its impact on trapped CO2 saturation. Pore-scale imaging showed the concurrent shrinkage and growth of CO2 ganglia, reduced morphological complexity, and enhanced connectivity, resulting from Ostwald ripening. Ganglia exhibited a size-dependent response: small ganglia dissolved and disappeared, intermediate ones shrank or grew, and large ganglia stabilized with occasional fragmentation. After waiting for 58 h with no flow, originally residual CO2 reconnected, and subsequent brine injection led to a decrease in saturation from 22.8% to 15.6%, consistent with previous estimates based on pore-scale modeling. This work suggests that measurements that ignore the effect of Ostwald ripening overestimate the residual saturation by a factor of approximately a third