Tootfinder

Quartet 🎵
四重奏 🎵
📷 Nikon F4E
🎞️ Ilford Pan 400
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When you are a Xogot user, every day is Xmas!
Performance, exploration, usability, live shader debugging and more!
https://blog.xogot.com/xogot-1-6-2-is-out/

Xogot 1.6.2 is out
We just published Xogot 1.6.2, a quick follow-up release to our launch of Xogot 1.6, powered by Godot 4.6. With performance improvements, a redesigned MultiMeshInstance3D populate workflow, a much more usable GridMap editor, and early access to the Godot 4.7 shader previewer. Performance We

Here's somebody's blog post about grackles' fondness for dropping feces in water, written from the perspective of an annoyed koi-pond owner. The author gives the usual explanation that behavior reduces nest predation (presumably because fecal smell is attractant). I couldn't find support for this hypothesis in the primary literature, however. Nor could I find support for the idea that a clean nest reduces parasites such as flesh-eating flies. But I'm not a birdologist so I could have missed the definitive paper. https://www.pondtrademag.com/blackbird-gift-sacs-the-airmail-no-pond-keeper-wants/

A discrete Boltzmann model with state-dependent power-law relaxation time for nonequilibrium transport in compressible flows
Demei Li, Zhongyi He, Huilin Lai, Yanbiao Gan, Hailong Liu, Pengfei Lin
https://arxiv.org/abs/2605.18216 https://arxiv.org/pdf/2605.18216 https://arxiv.org/html/2605.18216
arXiv:2605.18216v1 Announce Type: new
Abstract: Thermodynamic nonequilibrium effects play a central role in momentum and energy transport in compressible flows. In conventional BGK kinetic models, the relaxation time $\tau$ is taken as a constant, which neglects the dependence of the relaxation process on local macroscopic states. To overcome this limitation, we develop a discrete Boltzmann model with a density- and temperature-dependent power-law relaxation time, termed DTRT-DBM, in which $\tau=\tau_0(\rho/\rho_0)^a(T/T_0)^b$. This formulation extends the discrete Boltzmann framework to flows with spatially varying nonequilibrium intensity. The model is validated by the Sod shock tube and by analytical solutions for viscous stress and heat flux, demonstrating accurate recovery of both macroscopic wave structures and nonequilibrium quantities across shock waves, rarefaction waves, and contact discontinuities. On this basis, phase diagrams of viscous stress and heat flux are constructed to examine how these quantities depend on the power-law exponents $a$ and $b$. The extrema of these quantities depend exponentially on the model parameters and exhibit regime-dependent behaviour. The roles of $a$ and $b$ are not symmetric: the nonequilibrium response is more sensitive to $a$ when density gradients dominate, but more sensitive to $b$ when temperature gradients dominate. Within the parameter range and flow configurations examined here, higher-order viscous stress increases the growth rate of the total viscous-stress extremum, whereas higher-order heat flux reduces the growth rate of the total heat-flux extremum. These results show that the proposed model can capture different higher-order nonequilibrium responses in compressible flows and provides a framework for the modelling and analysis of multiscale nonequilibrium processes.
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Giants' Cam Skattebo won't alter approach after injury: I'm going to get back to 'running people over' https://www.nfl.com/news/giants-cam-skattebo-won-t-alter-approach-after-injury-i-m-going-to-get-bac…

Perfection Because It Doesn’t Exist 🌅
完美因为完美不存在 🌅
📷 Pentax 6x7
🎞️ Kentmere 400
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Shear alignment and tensorial Taylor--Aris dispersion of Brownian rods in a circular tube
Jingsen Feng, Xu Chu
https://arxiv.org/abs/2605.17614 https://arxiv.org/pdf/2605.17614 https://arxiv.org/html/2605.17614
arXiv:2605.17614v1 Announce Type: new
Abstract: Brownian rods disperse in pressure-driven flow through a coupling between axial shear, anisotropic translational diffusion and Jeffery--Brownian rotation. Classical tube Taylor--Aris theory treats transverse mixing as a scalar process, and existing passive-rod reductions have mainly addressed planar geometries. A circular tube adds two ingredients: the shear strength varies with radius and freely rotating rods sample a three-dimensional orientation space. We formulate a tensorial Taylor--Aris theory for dilute axisymmetric rods in Poiseuille flow by solving the local steady orientation Fokker--Planck problem and using its second moments to close a conservative axisymmetric transport equation. The long-wave reduction shows how each part of the diffusion tensor enters the one-dimensional limit. The radial diffusivity sets the invariant cross-sectional measure and the cell problem for the leading Taylor coefficient; the radial--axial component produces an inverse-P{\'e}clet correction to the migration speed; the axial component gives the direct diffusivity. The central mechanism is the streamwise alignment generated in high-shear annular layers. Alignment reduces radial diffusivity there, shifts the long-time sampling of the velocity profile toward slower streamlines, and amplifies the radial cell response. In strong shear this raises the Taylor coefficient by about \(23\%\) for aspect ratio \(p=1000\) and by about \(30\%\) in the infinitely slender limit, approaching the fully aligned bound. Direct simulations of the full tensorial equation validate the asymptotic coefficients. The same radial mixing operator also gives a Sturm--Liouville spectral model that tracks finite-time relaxation from different radial injections to the long-time Taylor regime.
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Giants' Cam Skaettbo won't alter approach after injury: I'm going to get back to 'running people over' https://www.nfl.com/news/giants-cam-skaettbo-won-t-alter-approach-after-injury-i-m-going-to-get-bac…

Elastic wave propagation governs impulse enhancement in pulsed jets through flexible nozzles
Paras Singh, Daehyun Choi, Saad Bhamla, Chandan Bose
https://arxiv.org/abs/2605.17319 https://arxiv.org/pdf/2605.17319 https://arxiv.org/html/2605.17319
arXiv:2605.17319v1 Announce Type: new
Abstract: Inspired by cephalopod jet propulsion through compliant funnels, this study investigates elastic wave propagation and energy exchange in passively deforming cylindrical nozzles through three-dimensional, two-way fluid-structure interaction simulations. Flexible nozzles with varying stiffness ($Eh = 75 - 500~\mathrm{N\,m^{-1}}$, where $E$ and $h$ are Young's modulus and nozzle thickness, respectively) are subjected to a pulsatile jet inflow at $Re \sim 4000$. Increasing nozzle flexibility reduces the deformation-wave speed in accordance with Moens-Korteweg scaling, thereby prolonging the nozzle expansion phase. This delayed expansion enhances jet entrainment and elastic energy storage while suppressing early shear-layer roll-up and vortex formation. During contraction, the stored elastic energy is released, thereby enhancing jet acceleration and vortex formation. For the most flexible nozzle, the primary vortex-ring circulation increases by 52.13%, the vortex convection distance by 9.00%, and the peak outlet kinetic energy flux by a factor of 4.62 compared with a rigid nozzle. These effects collectively yield a 61.92% increase in total hydrodynamic impulse. These findings identify passive wave-speed tuning via nozzle compliance as a mechanism to enhance pulsed-jet thrust for bio-inspired underwater propulsion.
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Mistakes and None Thereof III ❌
错误和当中没有错误 III ❌
📷 Nikon F4E
🎞️ Kentmere 400
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