Abstract: "In Navier–Stokes (NS) turbulence, large-scale turbulent flows inevitably determine small-scale flows. Previous studies using data assimilation with the three-dimensional (3-D) NS equations indicate that employing observational data resolved down to a specific length scale, ℓ<sup>3-D</sup><sub>∗</sub>, enables the successful reconstruction of small-scale flows. Such a length scale of ‘essential resolution of observation’ for reconstruction ℓ<sup>3-D</sup><sub>∗</sub> is close to the dissipation scale in three-dimensional NS turbulence. Here, we study the equivalent length scale in two-dimensional (2-D) NS turbulence, ℓ<sup>2-D</sup><sub>∗</sub>, and compare with the three-dimensional case. Our numerical studies using data assimilation and conditional Lyapunov exponents reveal that, for Kolmogorov flows with Ekman drag, the length scale ℓ<sup>2-D</sup><sub>∗</sub> is actually close to the forcing scale, substantially larger than the dissipation scale. Furthermore, we discuss the origin of the significant relative difference between the length scales, ℓ<sup>2-D</sup><sub>∗</sub> and ℓ<sup>3-D</sup><sub>∗</sub>, based on inter-scale interactions, ‘cascades’ and orbital instabilities in turbulence dynamics."
Abstract: "When the species composition of ecological communities changes over time, environmental drivers are often invoked as the most plausible explanation. Several lines of reasoning, however, suggest that such compositional change, called temporal species turnover, can similarly result from intrinsic ecosystem dynamics, even in a constant environment. The degree to which these two drivers contribute to observed turnover remains unclear. To address this conundrum, we analyse the well-established BioTIME database of surveys. We expect either an acceleration of turnover with accelerating climate change or constant turnover if intrinsic mechanisms dominate. Surprisingly we find instead that species turnover over short time intervals (1-5 years) has decelerated in significantly more communities during the last 100 years than it has accelerated, typically by one third. The observed slowing of turnover, we argue, could be understood—when intrinsic dynamics dominate—as resulting because anthropogenic environmental degradation or declines of regional species pools reduce the number of potential colonisers driving turnover. Our results suggest that observed past changes in species composition were often manifestations of natural, intrinsic ecosystem dynamics. Although one can expect environmental drivers to dominate species turnover eventually as climate change accelerates further, for now such attribution should be done with caution."
Abstract: "Ecological communities in heterogeneous environments assemble through the combined effect of species interaction and migration. Understanding the effect of these processes on the community properties is central to ecology. Here we study these processes for a single community subject to migration from a pool of species, with population dynamics described by the generalized Lotka-Volterra equations. We derive exact results for the phase diagram describing the dynamical behaviors, and for the diversity and species abundance distributions. A phase transition is found from a phase where a unique globally attractive fixed point exists to a phase where multiple dynamical attractors exist, leading to history-dependent community properties. The model is shown to possess a symmetry that also establishes a connection with other well-known models."
"Methods: The mindful endoscopy team, consisting of an endoscopist and endoscopy support practitioners (ESPs) was created. Nurse-led mindfulness comprised patient education on a range of relaxation methods just before the start of the procedure, and holistic and proactive patient support within a clear structure during it. Patient experience of awake oral and pharyngolaryngeal endoscopy (180 procedures) and transnasal panendoscopy (70 procedures) were recorded using the Gastrointestinal Endoscopy Satisfaction Questionnaire.
Results: Overall, 92.4% of patients were satisfied or very satisfied with their awake endoscopies and 96.4% indicated that they would be happy or very happy to undergo the same procedure undertaken by the same team again. At a mean follow-up of 14 months, 12 cancers had been detected and no cancers had been missed."
"Abstract. Atlantic Meridional Overturning Circulation (AMOC) is suggested to be in a bi-stable regime and might already be at the brink of a irreversible trajectory towards a complete shutdown–a so called tipping point. Such a tipping point requires a self-reinforcing feedback, for example one related to the upper ocean salt transport convergence to the North Atlantic subpolar gyre. We show that in Earth System Model simulations under abrupt high CO$_2$ forcing ($>$1.8 times the pre-industrial conditions), salt transport convergence is highly correlated with AMOC, indicating an active role for salinity in reinforcing AMOC decline. However, at weak or transiently increasing CO$_2$ forcing the relation is masked by internal variability in our model simulations and observationally constrained products. Our results suggest that with the present forcing levels, salinity reinforced AMOC decline is unlikely, and consequently, it is unlikely that AMOC would be close to a salt transport convergence induced tipping point."
Abstract: "Understanding the cold atomic hydrogen gas (H i) within cosmic filaments has the potential to pin down the relationship between the low density gas in the cosmic web and how the galaxies that lie within it grow using this material. We report the discovery of a cosmic filament using 14 H i-selected galaxies that form a very thin elongated structure of 1.7 Mpc. These galaxies are embedded within a much larger cosmic web filament, traced by optical galaxies, that spans at least $\sim 15$ Mpc. We find that the spin axes of the H i galaxies are significantly more strongly aligned with the cosmic web filament ( $\langle |\cos \psi|\rangle = 0.64 \pm 0.05$) than cosmological simulations predict, with the optically selected galaxies showing alignment to a lesser degree ( $\langle |\cos \psi|\rangle = 0.55 \pm 0.05$). This structure demonstrates that within the cosmic filament, the angular momentum of galaxies is closely connected to the large-scale filamentary structure. We also find strong evidence that the galaxies are orbiting around the spine of the filament, making this one of the largest rotating structures discovered thus far, and from which we can infer that there is transfer of angular momentum from the filament to the individual galaxies. The abundance of H i galaxies along the filament and the low dynamical temperature of the galaxies within the filament indicates that this filament is at an early evolutionary stage where the imprint of cosmic matter flow on galaxies has been preserved over cosmic time."
Abstract: "Simone Weil is one of the most prominent 20th century French philosophers. She is the sister of Andr{é} Weil, the renowned mathematician, the father of modern algebraic geometry and the initiator of the Bourbaki group. Simone and Andr{é} Weil shared a love for literature, mathematics, science and philosophy. My aim in this article is to convey, based on their writings and their correspondence, the idea that Pythagoreanism was a central element of their thought. I will put this into context, talking first about the life and work of each of them, showing how much they were linked by essential common ideas, even though their life paths were very different, and how, ultimately, Pythagorean mathematics and philosophy became naturally part of their respective intellectual worlds. The article is the written version of a lecture I gave in October 2025, at the conference ``The Life and Contribution of Pythagoras to Mathematics, Sciences, and Philosophy'' that took place on October 3-4, 2025 at the Cyprus University of Technology in Limassol"
Abstract: "For over 600 years, debates over noncompete clauses have centered on whether they function as efficient contracting tools or anticompetitive restraints on workers. This article reassesses that debate in light of recent policy attention and new empirical and theoretical research. Proponents argue that noncompetes are necessary to protect investments in training and trade secrets, increasing productivity and wages. However, recent studies indicate that the widespread use of noncompetes—frequently extending beyond roles involving sensitive information—and their enforceability lower mobility, wages, innovation, and entrepreneurship. Moreover, in many cases, less restrictive contractual terms appear to safeguard firm interests. Evidence of spillovers to other workers and across state boundaries, as well as behavioral effects even when noncompetes are unenforceable, raises questions about whether existing state-level enforcement regimes adequately address their observed impacts."
Abstract: "Boltzmann distributions are used in statistical mechanics to describe how the states of a system are distributed at a given temperature. We give a novel characterization of this family as the unique one satisfying independence for uncoupled systems. The theorem boils down to a statement about endomorphisms of the convolution semi-group of finitely supported probability measures on the natural numbers, or, alternatively, about endomorphisms of the multiplicative semi-group of polynomials with non-negative coefficients."
Abstract: "Growing evidence suggests that peripheral diseases serve as risk factors for dementia, but the population-level burden of dementia associated with various peripheral diseases has remained unknown. Here, by conducting a systematic review and Bayesian meta-analyses to estimate the relative risks of 26 peripheral diseases across 9 systems with dementia, including 202 articles searched from the PubMed until 6 September 2024, we identified 16 peripheral diseases as associated with increased risk of dementia. With the relative risks estimated from meta-analyses, prevalences extracted from the Global Burden of Disease Study, and communalities among these 16 peripheral diseases derived from the UK Biobank, we analysed the population attributable fractions (PAFs) of these 16 peripheral diseases for dementia, stratified by sex, age, sociodemographic index level, world region and country, and trends from 1990 to 2021. Globally, these peripheral diseases collectively were related to a combined PAF of 33.18% (95% confidence interval (CI) 16.80–48.43) of dementia burden, corresponding to 18.8 million prevalent cases. The leading ten PAF contributors were periodontal diseases (6.10%, 95% CI 0.95–10.28), cirrhosis and other chronic liver diseases (5.51%, 95% CI 1.77–8.86), age-related and other hearing loss (4.70%, 95% CI 3.51–6.06), blindness and vision loss (4.30%, 95% CI 3.43–5.05), type 2 diabetes mellitus (3.80%, 95% CI 3.06–4.53), chronic kidney disease (2.74%, 95% CI 1.53–4.02), osteoarthritis (2.26%, 95% CI 0.41–4.12), stroke (1.01%, 95% CI 0.86–1.17), ischaemic heart disease (0.97%, 95% CI 0.69–1.29) and chronic obstructive pulmonary disease (0.92%, 95% CI 0.34–1.54). This study revealed that a series of peripheral diseases were associated with increased risk of dementia and collectively were related to about one-third of the global dementia burden, highlighting the need for targeted public health strategies."
Abstract: "Parkinson’s disease (PD) is an incurable neurological disorder that often begins insidiously with sleep disturbances and somatic symptoms, progressing to whole-body motor and cognitive symptoms1,2,3,4,5. Dysfunction of the somato-cognitive action network (SCAN)—which is thought to control action execution6,7 by coordinating arousal, organ physiology and whole-body motor plans with behavioural motivation—is a potential contributor to the diverse clinical manifestations of PD. To investigate the role of the SCAN in PD pathophysiology and treatments (medications, deep-brain stimulation (DBS), transcranial magnetic stimulation (TMS) and MRI-guided focused ultrasound stimulation (MRgFUS)), we built a large (n = 863), multimodal, multi-intervention clinical imaging dataset. Resting-state functional connectivity revealed that the substantia nigra and all PD DBS targets (subthalamic nucleus, globus pallidus and ventral intermediate thalamus) are selectively connected to the SCAN rather than to effector-specific motor regions. Importantly, PD was characterized by specific hyperconnectivity between the SCAN and the subcortex. We therefore followed six PD cohorts undergoing DBS, TMS, MRgFUS and levodopa therapy using precision resting-state functional connectivity and electrocorticography recording. Efficacious treatments reduced SCAN-to-subcortex hyperconnectivity. Targeting the SCAN instead of effector regions doubled the efficacy of TMS treatments. Focused ultrasound treatment benefits increased when the target was closer to the thalamic SCAN sweet spot. Thus, SCAN hyperconnectivity is central to PD pathophysiology and its alleviation is a hallmark of successful neuromodulation. Targeting functionally defined subcortical SCAN nodes may improve existing therapies (DBS, MRgFUS), whereas cortical SCAN targets offer effective non-invasive or minimally invasive neuromodulation for PD."
Abstract: "In Navier–Stokes (NS) turbulence, large-scale turbulent flows inevitably determine small-scale flows. Previous studies using data assimilation with the three-dimensional (3-D) NS equations indicate that employing observational data resolved down to a specific length scale, ℓ<sup>3-D</sup><sub>∗</sub>, enables the successful reconstruction of small-scale flows. Such a length scale of ‘essential resolution of observation’ for reconstruction ℓ<sup>3-D</sup><sub>∗</sub> is close to the dissipation scale in three-dimensional NS turbulence. Here, we study the equivalent length scale in two-dimensional (2-D) NS turbulence, ℓ<sup>2-D</sup><sub>∗</sub>, and compare with the three-dimensional case. Our numerical studies using data assimilation and conditional Lyapunov exponents reveal that, for Kolmogorov flows with Ekman drag, the length scale ℓ<sup>2-D</sup><sub>∗</sub> is actually close to the forcing scale, substantially larger than the dissipation scale. Furthermore, we discuss the origin of the significant relative difference between the length scales, ℓ<sup>2-D</sup><sub>∗</sub> and ℓ<sup>3-D</sup><sub>∗</sub>, based on inter-scale interactions, ‘cascades’ and orbital instabilities in turbulence dynamics."
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