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Fast Ion Interaction with Turbulence Mediated by Zonal Flows in Tokamak Plasmas: Overview of the Recent Insights
Get PDFRecent findings on improved thermal plasma confinement in the presence of large-scale Alfvén Eigenmodes in tokamak plasmas have sparked a great interest in the complex physics at play, as it is relevant for next-generation fusion device optimization. These studies must be framed within the latest two decades of efforts in analyzing the various mechanisms through which the fast ions, i.e. ions with much larger energy than that of thermal ions, can interact with the background turbulence and, remarkably, reduce or even suppress the latter in magnetized plasmas. This contribution aims at reviewing the latest results about experimental and modeling observation of reduced outward ion heat flux triggered by the nonlinear and multi-scale interplay of fast-ion-driven modes and background turbulence, and framing it within the broad knowledge on the well-established fast-ion mechanisms reducing the tokamak plasma turbulence
Rapamycin Exerts Its Geroprotective Effects in the Ageing Human Immune System by Enhancing Resilience Against DNA Damage
Get PDFmTOR inhibitors such as rapamycin are among the most robust life‐extending interventions known, yet the mechanisms underlying their geroprotective effects in humans remain incompletely understood. At non‐immunosuppressive doses, these drugs are senomorphic, that is, they mitigate cellular senescence, but whether they protect genome stability itself has been unclear. Given that DNA damage is a major driver of immune ageing, and immune decline accelerates whole‐organism ageing, we tested whether mTOR inhibition enhances genome stability. In human T cells exposed to acute genotoxic stress, we found that rapamycin and other mTOR inhibitors suppressed senescence not by slowing protein synthesis, halting cell division, or stimulating autophagy, but by directly reducing DNA lesional burden and improving cell survival. Ex vivo analysis of aged immune cells from healthy donors revealed a stark enrichment of markers for DNA damage, senescence, and mTORC hyperactivation, suggesting that human immune ageing may be amenable to intervention by low‐dose mTOR inhibition. To test this in vivo, we conducted a placebo‐controlled experimental medicine study in older adults administered with low‐dose rapamycin. p21, a marker of DNA damage‐induced senescence, was significantly reduced in immune cells from the rapamycin compared to placebo group. These findings reveal a previously unrecognised role for mTOR inhibition: direct genoprotection. This mechanism may help explain rapamycin's exceptional geroprotective profile and opens new avenues for its use in contexts where genome instability drives pathology, ranging from healthy ageing, clinical radiation exposure and even the hazards of cosmic radiation in space travel
Automated landmark detection for assessing hip conditions: a cross-modality validation of MRI versus X-ray
Get PDFMany clinical screening decisions are based on angle measurements. In particular, FemoroAcetabular Impingement (FAI) screening relies on angles traditionally measured on x-rays. However, assessing the height and span of the impingement area requires also a 3D view through an MRI scan. The two modalities inform the surgeon on different aspects of the condition. In this work, we conduct a matchedcohort validation study (89 patients, paired MRI/x-ray) using standard heatmap regression architectures to assess cross-modality clinical equivalence. Seen that landmark detection has been proven effective on x-rays, we show that MRI also achieves equivalent localisation and diagnostic accuracy for cam-type impingement. Our method demonstrates clinical feasibility for FAI assessment in coronal views of 3D MRI volumes, opening the possibility for volumetric analysis through placing further landmarks. These results support integrating automated FAI assessment into routine MRI workflows
Driving impacts through science-practitioner partnership: Professionalising water service delivery in rural Bangladesh
Get PDFAcademic research is under increasing pressure to demonstrate tangible societal, environmental, and economic impact, prompting increased engagement between scientists and practitioners. This paper investigates how such partnerships evolve, how science contributes across different phases of the policy process, and what conditions enable or constrain their effectiveness. It does so through the case of SafePani, a professional rural water service delivery model in Bangladesh. Conceptualised and piloted through UK-based research funding in schools and healthcare facilities, SafePani was later scaled under a six-year, results-based funding contract co-funded by the Government of Bangladesh. The study integrates the multi-level perspective, actor-centred institutionalism, and institutional work to analyse the micro-level activities that actors engaged in to build networks, shape dominant discourses and drive institutional change. Findings show that SafePani’s success stemmed not only from technical innovation but from its strategic adaptability. This included evolving actor configurations from academic-led research to government-led implementation, mobilising financial, intellectual, and political capital, engaging credible boundary actors to build trust, and engaging bureaucratic champions. Crucially, institutional stamina of the government, the model’s low cost and public value, and the funding flexibility enabled actors to overcome institutional inertia. SafePani offers a replicable example of how interdisciplinary science, sustained engagement, and contextual adaptation can drive institutional reform in complex policy environments
Helping patients with persecutory delusions find safety
No full textAt the heart of a persecutory delusion is an incorrect perception of threat from others. This makes the person feel very unsafe. Overcoming such delusions therefore means establishing a sense of safety, and thus a realisation that there is no current threat. Discovering that one is safe functions as the counterweight to feeling unsafe. The counterweight shifts expectations and changes beliefs. In this article we describe how safety may be learned. This includes how to engage patients, framing the finding of safety, switching from threat to safety mode, using experiential learning, and consideration of blocking beliefs that may prevent new learning. Key points are to: frame intervention as an opportunity to find greater safety in the world so that meaningful activities can be resumed; repeatedly measure the learning of safety; make new benign associations with the internal and external cues driving the delusions; keep the new learning to the present and future, suitably circumscribed for an individual, so that potential for discord is limited; carry out safety-establishing behavioural experiments that allow for the dropping of defence behaviours, the reframing of evidence for the delusion, and diminish the pervasiveness of the perceived threat; and help patients move from situation-specific instances of safety to more generalised belief change. Enabling patients to re-discover safety in their everyday lives — decisively tipping the scales in favour of the counterweight — is the most transformational element of successful psychological intervention for persecutory delusions
A vibronic coupling model to study the nonadiabatic dynamics of polyenes
Get PDFWe develop a linear vibronic coupling (LVC) model for polyenes described by the extended Hubbard-Peierls Hamiltonian. This model is applied to trans-hexatriene to benchmark quantum-classical dynamics methods against fully quantum simulations. We find that surface-hopping methods describe short times more accurately than multitrajectory Ehrenfest. None of the quantum-classical methods studied obtain the longtime population oscillations found in fully quantum simulations. Varying the parameters of the LVC Hamiltonian, we find that surface hopping reproduces the correct trends in the long-time dynamics across a wide range of parameters, but generally overestimates the degree of internal conversion. On the other hand, multi-trajectory Ehrenfest gives more accurate long-time populations in proximity to the hexatriene parameter set
A comprehensive search for high-velocity X-ray sources: new compact object binary candidates in the Gaia era
Get PDFWe perform a comprehensive search for high-velocity X-ray sources with large X-ray/optical flux ratios (), identifying candidates for interacting black hole or neutron star binaries potentially accelerated by supernova natal kicks. We cross-match X-ray points sources from a variety of catalogues (Chandra, XMM–Newton, Swift, and eROSITA) with Gaia DR3. Using Gaia coordinates, parallaxes, and proper motions, we compute peculiar velocities () relative to Galactic disc rotation. Remaining agnostic about radial velocities (RVs), we vary RVs to find the minimum possible values (). Uncertainties on are estimated via Monte Carlo resampling, and we select X-ray sources that have lower limits on and high values. We show that this velocity threshold excludes most contaminants (e.g. cataclysmic variables and active binaries) while retaining a sensible fraction of compact object binaries, demonstrating that could serve as an effective indicator for the presence of a neutron star or black hole companion. Our selection yields a sample of sources, from which we construct a gold sample of sources that have relatively well-constrained astrometry and confident optical counterparts. Follow-up is necessary to confirm and characterise their high-energy emission, as well as a Galactic disc vs. halo origin
Ionic pathways to neuromorphic function: direct visualization of oxygen migration in interface synaptic memristive devices
No full textData was created ifrom June 2025 to January 2026. Data was processed with Python tools and can be plotted with any plotting softwar
Cohort profile: Infant Gut Bacterial Study in Nigeria (INBUGS-NG)
Get PDFPURPOSE: The Infant Gut Bacterial Study in Nigeria (INBUGS-NG) investigates how delivery mode, antibiotic exposure, feeding practices and environmental factors shape gut microbiome development and acquisition of antibiotic resistance genes (ARGs) during the first year of life in northern Nigeria.
PARTICIPANTS: Between February and July 2024, 90 mother-infant dyads were enrolled at a tertiary hospital in Kano city, Nigeria. This was a prospective longitudinal cohort with follow-ups at 10 scheduled time points: days 0, 1, 3, 5, 7, 14, 28, 90, 180 and 365. We also intensified stool sampling after infant antibiotic administration, enabling dense early-life sampling. To date, the cohort has contributed 480 infant stool samples, 232 maternal rectal swabs, 254 breast milk samples and 806 environmental samples (total 1772). In parallel, socio-demographic, clinical and cultural data were collected using Research Electronic Data Capture (REDCap) and household visit diaries.
FINDINGS TO DATE: Baseline data show that 84/90 mothers (93.3%) received postpartum antibiotics, and 26/90 infants (28.9%) received antibiotics within the first 3 months of life. Only 8% of infants were exclusively breastfed, with early water supplementation common. Caesarean deliveries accounted for 25% of births, and the mean gestational age was 38.5 weeks. Across the cohort, high retention was achieved, and the study has generated a unique long-read metagenomic resource from an African infant population, with analyses ongoing.
FUTURE PLANS: Shotgun long-read metagenomic sequencing (Oxford Nanopore) will enable strain-level and plasmid-level profiling of microbial communities and ARGs. Planned analyses include associations between early-life exposures and resistome dynamics, as well as cross-cohort comparisons with a parallel study in Pakistan. Follow-up will continue through 12 months