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Radio activity from the rapidly rotating T dwarf 2MASS 2228-4310
Get PDFWe present the detection of 2MASS J22282889−4310262 (2M2228), a T6/T6.5 brown dwarf, using the Karl G. Jansky Very Large Array archival data observed at C band (4–8 GHz) over two observing epochs ( min). 2M2228 is detected at time and frequency averaged Stokes I and V peak flux densities of and in the first epoch and and in the second epoch. This discovery constitutes the eighth and, notably, the most rapidly rotating T dwarf detected to date at radio wavelengths. Our observations reveal highly polarized bursts at fractional polarization ratios per cent. Using Stokes I light curves, we measure occurrence intervals of and min in the two observing epochs, respectively, with the first burst aligning within a half-period time-scale of the the previously measured mid-infrared photometric period of min. We attribute the emission to the electron cyclotron maser emission and constrain the magnetic field strength to kG. We emphasize that the periods inferred are provisional considering the short observing durations. The combination of previously demonstrated atmospheric stability and newly detected radio emission in 2M2228 makes it a promising laboratory for testing magnetospheric currents-driven auroral models. Future coordinated James Webb Space Telescope and radio observations will further probe the link between auroral activity and atmospheric dynamics in this brown dwarf
Geographies of halal: slaughter, ethics and edibility in the British halal meat industry
Get PDFThis thesis focuses on how halal meat production and consumption in the UK is shaped by relations of distance and proximity to animal killing, in order to understand how the intersection of sacred and secular values shapes producers’ and consumers’ ethical dispositions towards the animals they rear, kill and consume. Throughout the thesis, I draw upon interviews with halal meat producers, retailers, and certifiers, as well as slaughterhouse and farm visits and responses to an in-depth online consumer survey. My work develops literature in animal geographies, critical animal studies and animal ethics on distancing animal death, as well as debates in food geographies and cultural anthropology on material semiotics of consumption and reconnecting with food production. The results chapters progress through the halal meat supply chain, with each chapter focusing on a specific practice of production or consumption, and the spaces and distance/proximity relations implicated in each. The first results chapter addresses slaughtering, situated in the modern British halal slaughterhouse, the predominant site of animal killing for halal meat in the UK. The chapter demonstrates how the halal ritual creates unique configurations of proximity and distance regarding animal death, both leaving open the ability to be affected and providing protection from the emotional impacts of killing animals for food. However, there is a tension between practices of ritual slaughter and the realities imposed by commercial demands. The next three results chapters move to the realm of consumption, with the second results chapter examining halal consumers’ witnessing of animal killing and rearing, told through the narrative of significant space-times of slaughter and their (un)ethical effects. I argue that British Muslim consumers make an interesting case for studying relations with animal death because, by virtue of the unique configurations of their identity, they straddle ‘domestic’ and ‘postdomestic’ animal relations. The following chapter explores how knowledge intermediaries shape distance/proximity relations in common sites of halal meat purchasing, most notably the butcher shop, and how these are changing with time. The final results chapter explores how the embodied eating experience affects halal consumers’ proximity and/or distance to food animals’ lives and deaths and how they perceive the implications of this for their bodies and souls, blurring sacred and secular concerns. Throughout the thesis, I draw attention to the spatial, multi-scalar, temporal, embodied, contingent and culturally- and religiously-laden nature of halal meat consumption, developing geographical work on the ethics and politics of meat production and consumption
Inflationary attractors and radiative corrections in light of ACT data
Get PDFIn light of the recent results from the Atacama Cosmology Telescope (ACT), which have provided a notable shift in the constraints on (ns, r) and placed several otherwise viable models of inflation in tension with the latest data, we investigate the possible effects that radiative corrections can have on ξ-attractor and α-attractor models of inflation. These models, which share much in common with Starobinsky inflation, have likewise been put under pressure by these results. We find that percent (and even sub-percent) level radiative corrections can easily shift both of these classes of inflation models comfortably into the regions of parameter space favoured by the most recent constraints. However, the flexibility under such corrections calls into question to what extent it is possible to precisely pin down model-specific predictions for important cosmological observables
Clinical Grading of Artificial Intelligence‐Based 3D Fetal Brain Segmentations: A Cross‐Vendor Evaluation of Deep Learning in Fetal Neuroimaging
Get PDFObjective: To evaluate the performance of automated (sub)cortical fetal brain segmentation methods on a novel 3D ultrasound dataset acquired from a different vendor, and to introduce a clinician‐focused visual evaluation framework complementary to the widely used Dice Similarity Coefficient (DSC). Method: This cohort study included 270 volumes (141 fetuses, 19–26 + 6 weeks gestation). Deep learning models were applied to segment the cavum septum pellucidum et vergae (CSPV), lateral posterior ventricle horn (LPVH), choroid plexus (ChP), cerebellum (CBM) and cortical plate (CoP) on a new dataset acquired by a different ultrasound vendor. Segmentations were visually graded (1–4 = high to poor quality) based on predefined criteria. Grades were analyzed as “adequate” (1 + 2) or “inadequate” (3 + 4). Results: CSPV, ChP and CBM showed the best segmentation grades (> 83.1% grade 1, > 90.5% adequate) and were robust across gestation. LPVH showed the lowest performance (73.9% adequate). Overall segmentation quality across all structures was high (87.2% adequate). Intra‐ and interobserver agreement was 90.1% and 82.1%–92.7%, respectively. Conclusion: These deep‐learning methods can reliably segment (sub)cortical structures when applied to a novel dataset acquired with a different ultrasound vendor, demonstrating robustness. Incorporating visual assessment alongside quantitative metrics provides insight into anatomical accuracy and clinical usability
Evaluation of Large Language Models in the Diagnosis, Urgency Triage, and Initial Management of Ophthalmic Emergencies
Get PDFIntroduction Artificial intelligence (AI) technologies are progressing rapidly and becoming an integral part of how healthcare professionals obtain medical knowledge. Large language models (LLMs) now enable clinicians to have direct access to medical guidance and support in clinical reasoning. In ophthalmology, where prompt identification of sight-threatening symptoms is essential, these tools can offer diagnostic support, urgency triaging, and initial management guidance, thus potentially reducing delays in care and improving referrals. Limited evidence exists regarding their accuracy, reliability, and safety in eye emergencies. This study aims to compare the diagnostic accuracy, urgency triage, and initial management advice generated by the three leading LLMs, to evaluate their prospective role in the early assessment and management of acute eye presentations. Methods This cross-sectional study compared the performance of three LLMs, including ChatGPT-5 (2025, OpenAI, San Francisco, CA, USA), Google Gemini 2.5 Pro (2025, Google DeepMind, London, UK), and Claude Opus 4.1 (2025, Anthropic, San Francisco, CA, USA), using a set of 40 standardised ophthalmic emergency vignettes across five key subspecialties within ophthalmology. Each vignette was entered into each LLM, and responses were evaluated for diagnostic accuracy (2 points), urgency recognition (2 points), initial management advice (3 points), and identification of red flag symptoms (1 point). Each vignette case had a minimum possible score of 0 and a maximum possible score of 8. Scores were compared across the three models, and statistical significance was assessed using the Wilcoxon signed-rank and Friedman tests. Results In this analysis, 40 clinical vignettes were each evaluated across three LLMs: ChatGPT-5, Gemini 2.5 Pro, and Claude Opus 4.1, producing 120 responses in total. Overall scores were similar across ChatGPT (6.88 ± 1.16), Gemini (7.03 ± 1.21), and Claude (6.93 ± 1.19), with no significant differences identified on statistical analysis. Additional comparison across diagnostic scores, urgency triage, red flag recognition, and management scores yielded no significant differences between any of the LLMs. Further subgroup analysis comparing subspecialties similarly yielded no significant differences across all LLMs. Conclusion This study demonstrates that ChatGPT-5, Google Gemini 2.5 Pro, and Claude Opus 4.1 show consistent performances in diagnosing, triaging, and providing management advice for ophthalmic emergencies from text-based clinical vignettes. All models achieved diagnostic accuracies above 80% and provided management advice in line with recognised ophthalmology guidelines, with no statistically significant differences between their overall performances. These findings showcase the potential of LLMs as support tools for ophthalmic clinical advice, particularly for non-specialists, where guidance is valuable. However, their diagnostic errors and consequent suboptimal management advice emphasise the need for ongoing development and human supervision to ensure safety before widespread clinical application
MEGATRON: disentangling physical processes and observational bias in the multi-phase ISM of high-redshift galaxies
Get PDFNow detected out to redshifts of , the rest-frame ultraviolet and optical spectra of galaxies encode numerous physical properties of the interstellar medium (ISM). Accurately extracting these properties from spectra remains a key challenge that numerical simulations are uniquely suited to address. We present a study of the observed ISM of galaxies in MEGATRON: a suite of cosmological radiation hydrodynamics simulations coupled to on-the-fly non-equilibrium thermochemistry, with multiple prescriptions for star formation/feedback and parsec-scale resolution; capable of directly predicting spectroscopic properties of early galaxies. We find that irrespective of feedback physics used, the ISM of high-redshift galaxies is denser, less metal enriched, and subject to higher ionization parameters and radiation fields compared to similar mass galaxies in the local Universe -- in agreement with interpretations of JWST observations. Using common observational techniques to infer bulk galaxy properties, we find that ISM gas density controls the slope of the mass-metallicity relation. Similarly, at the densities reached in some high-redshift galaxies, O32 becomes a density tracer rather than one of ionization parameter. This motivates the use of other line ratios like C43 and N43 to infer the ionization state of the gas. Finally, various feedback models populate different regions of strong-line diagnostic diagrams as the line ratios are sensitive to the feedback-modulated density-temperature structure of the ISM. Therefore, observed strong-line diagnostics can provide a strong constraint on the underlying physics of star formation and feedback in the high-redshift Universe
The molecular mechanisms of cytokine-mediated activation of human CD8+ T cells
Get PDFBackground: CD8+ T cells can be activated through both TCR-dependent and TCR-independent pathways, the former response was shown to be largely regulated by mTORC2 over mTORC1. This raises the question of whether TCR-independent CD8+ T cell activation also involves the mTOR pathway and if so, which complex dominates. Additionally, because mTORC1 has been shown to regulate IRE1-α during ER stress, this study aims to explore whether the mTORC1-IRE1α pathway contributes to cytokine-induced CD8⁺ T cell activation, especially in NKG2A⁺ T cells and MAIT cells, known to be hyperresponsive to IL-12 and IL-18.Methods: Human primary peripheral blood mononuclear cells (PBMCs), purified CD8+ T cells and total T cells were used in this study. Small guide RNA and Cas9 protein or chemical inhibitors were used to study the function of proteins including mTORC1, mTORC2 and IRE1α. The knockout efficiency was assessed by western blotting. The activity of mTOR complexes was measured by phospho-flow cytometry (Phosflow). The expression of IFN-γ in CD8+ T cells or total T cells were measured by enzyme-linked immunosorbent assay (ELISA) or flow cytometry. The phenotype and the activation of CD8+ or CD3+ subsets were assessed by flow cytometry.Results: Chemical inhibition of mTORC1 had a more pronounced downregulation effect on cytokine-induced IFN-γ production than mTORC2 in total CD8+ T cells. Both chemical inhibition and genetic knockout of IRE1α potently supressed XBP1s expression and reduced the production of cytokine-induced IFN-γ in total CD8+ T cells. Regulation of cytokine-mediated activation by mTOR and IRE1α was further confirmed in CD8+NKG2A+CD161+ T and MAIT cells. Despite the shared feature of hyperresponsiveness to IL-12 and IL-18 by CD8+NKG2A+CD161+ T and MAIT cells, the former are less sensitive to glycolysis inhibition.Conclusions: In contrast to TCR-dependent activation, cytokine-induced CD8+ T cell activation is dependent more on mTORC1 than mTORC2 signalling. The regulation of cytokine-mediated activation by mTOR was partially dependent on IREα-XBP1s pathway. Additionally, NKG2A+CD161+ T and MAIT cells exhibit similar functional characteristics in response to cytokine stimulation but differed in energy utilisation
Fetal Growth Restriction at a Universal Late Third‐Trimester Scan and Relationship With Adverse Outcome: Retrospective Cohort Study
Get PDFObjective: To examine the contribution of fetal growth restriction ultrasound phenotypes to adverse perinatal outcomes at term. Design: Retrospective population‐based cohort study. Setting: John Radcliffe Hospital, Oxford, UK where universal ultrasound at 35+1–36+6 weeks is performed. Population: Congenital abnormalities and births before the scan were excluded. Singleton foetuses were categorised as five mutually exclusive phenotypes using a hierarchical approach: ISUOG fetal growth restriction (FGR), according to Delphi criteria; Constitutional small‐for‐gestational‐age (SGA) (estimated fetal weight [EFW] 95th centile; AGA with slowing abdominal circumference growth velocity (ACGV 24 h, or perinatal death); severe SGA at birth; neonatal unit admission; obstetric interventions. Results: Among 45 179 pregnancies, 54 SBs (0.1%) and 253 CAOs (0.6%) occurred. Normal AGA foetuses at the 35+1–36+6 week scan accounted for 82% of all pregnancies and for 43 (79.6%) SBs and 205 (81%) with the CAO, yet only 37.3% of neonates born with severe SGA. The absolute risk of SB and CAO was similar in all groups (0.1%–0.2%). Conclusions: Term FGR and ‘normal’ babies have similar perinatal risks, presumably because of intervention. Despite a detection rate of 62.7% for severe SGA, most adverse outcomes occurred in pregnancies with a normal scan
Efficacy of Pirtobrutinib Monotherapy in Treatment-Naïve Chronic Lymphocytic Leukemia: A Bayesian Network Meta-Analysis of Randomized Controlled Trials
Get PDFPrecision Is Not Enough: When Tools Outpace Translation in Ocular Gene Therapy
Get PDFAdvances in molecular biology have positioned the eye as a leading platform for gene therapy, owing to its surgical accessibility, relative immune privilege, and the ability of the contralateral eye to serve as an anatomical control. We trace the historical evolution of gene discovery, synthesize current gene therapy strategies for inherited and acquired ocular disorders, critically evaluating the limitations of CRISPR and related genome-editing technologies, and examine the key scientific and translational challenges that must be addressed for genetic therapies to be integrated into routine ophthalmic practice