@heiseonline@social.heise.de2026-05-26 13:04:01
@presseportal_pol_NDS@frawas.de2026-05-26 13:33:12
POL-WOB: Pkw in Brand gesetzt - Polizei sucht Zeugen Wolfsburg (ots) - Wolfsburg, Detmerode, Kurt-Schumacher-Ring 26.05.2026, 02.47 Uhr Unbekannte Täter setzten in der Nacht zu Dienstag einen Pkw in Brand. Der Pkw wurde vollständig zerstört. Ein Zeuge verständigte die Polizei, nachdem er auf einem ... https://www.pressep…
@memeorandum@universeodon.com2026-06-25 20:55:45
Texas Public School Students May Soon Be Required to Read the Bible (Sarah Mervosh/New York Times)
https://www.nytimes.com/2026/06/25/us/texas-schools-book-list.html?unlocked_article_code=1.s1A.pElm.SNquRN8zQurQ&smid=url-share
http://www.memeorandum.com/260625/p109#a260625p109
@arXiv_physicsmedph_bot@mastoxiv.page2026-06-23 08:13:11
Dosimetric Quantification of a Commercial Dual-Tube kV X-Ray System for Preclinical FLASH Research
Luka Matej Devenica, Lixiang Guo, Mohammad Rezaee, Ken Kang-Hsin Wang
https://arxiv.org/abs/2606.23401 https://arxiv.org/pdf/2606.23401 https://arxiv.org/html/2606.23401
arXiv:2606.23401v1 Announce Type: new
Abstract: A kV dual tube system has been disseminated as a commercial research platform for preclinical FLASH radiotherapy (RT). Because the tubes are arranged in a parallel opposed geometry, both output symmetry and time resolved tube synchronization are critical for achieving sufficiently high dose rates (DR) and reproducible study results. We quantified tube output asymmetry observed in depth dose measurements as well as tube synchronization and evaluated their impact on FLASH studies. The dual-tube system defines dose per pulse as the combined single pulse output from both tubes, with DR given by dose per pulse/pulse length. 3D dose distributions were reconstructed from film measurements to assess the impact of output discrepancies. Pulse synchronization between tubes was characterized using a scintillator with 1 ms resolution. We showed >20% discrepancies in output at nominally equal mA/ms settings. After we compensated such discrepancy by decreasing the current of the tube with higher output, the inter tube output difference was reduced to <1%, restoring symmetrical depth dose. We further simulated an in vivo intestinal irradiation in which naive tube settings resulted in >22% of the organ volume receiving >102% of the prescribed dose, compared with <7% when output compensation was applied. We identified a 10.2 /- 7.0ms synchronization jitter between tubes, which disproportionately impacts the DR at low dose-per-pulse settings, particularly relevant for fractionated studies. Corresponding quality assurance (QA) was designed to monitor tube synchronization over time. We quantified the dosimetric impact of asymmetric output and synchronization and demonstrated implications for preclinical studies. The proposed methodology and QA would mitigate and monitor these effects, ensuring study reproducibility.
toXiv_bot_toot
@heiseonline@social.heise.de2026-07-21 08:54:06
@grumpybozo@toad.social2026-06-15 22:49:23
If we let the orbital datacenter scams get to the point of launching, we deserve the Kessler Syndrome we get.
Sun-synch terminator-riders are in a limited orbital space. Many current residents belong to governments, as it’s a useful surveillance orbit. Once upon a time it’s the sort of thing that a U.N. body might regulate. Suggesting that now just seems like a joke…
@jake4480@c.im2026-05-18 06:27:27
Apparently there are too many bears in Japan, they've been using robotic wolves to keep them at bay, and they're running low on the robot wolves.
Just not the headline I expected to read today 😂🐻🐺 https://www.popsci.com/environment/japan-robot-wolf-army
@arXiv_physicsfludyn_bot@mastoxiv.page2026-07-23 08:09:05
The spectral picture of self-similar collapse in the Constantin-Lax-Majda equation
Jie Xu
https://arxiv.org/abs/2607.19762 https://arxiv.org/pdf/2607.19762 https://arxiv.org/html/2607.19762
arXiv:2607.19762v1 Announce Type: new
Abstract: We give a spectral description of the self-similar collapse profile of the Constantin-Lax-Majda (CLM) equation, the $a=0$ anchor of the generalized family $w_t a\,u\,w_x = u_x\,w$, $u_x = Hw$. Linearizing about the exact profile $\Omega(y) = -y/(y^2 1/4)$ and realizing $L_0$ as a closed operator on the origin-$H^2$ space, we prove three things at $a=0$. Its essential spectrum meets the closed half-plane $\{\mathrm{Re}\,\lambda \ge -1/2\}$ in the single vertical line $\{\mathrm{Re}\,\lambda = -1/2\}$: the line is placed by a log-widening Weyl sequence, and an explicit Hardy-Mellin resolvent bound constructively empties the rest of the half-plane apart from $0$ and $1$. Its full point spectrum over $\mathbb{C}$, on the odd realization, is exactly $\{0,1\}$, the scaling and time-shift symmetry modes, with no embedded eigenvalues; removing these by the standard modulation leaves a spectral gap of $1/2$ on $X$. The linear semigroup and its exact decay rate $e^{-\tau/2}$ are computed in closed form, but on a weighted space of the conjugated variable reached from $X$ by a bounded transfer map; we keep the two separate, since $L_0$ is non-normal and a spectral gap does not by itself give a decay rate in the $X$ norm. A realization dichotomy identifies the in-strip smear of generic discretizations as the faithful spectrum of the maximal $L^2$ realization, which origin-$H^2$ removes. For $a>0$ we prove a conditional two-line inclusion for each admissible smooth focusing profile, recompute the branch $c_l(a)$ of Lushnikov, Silantyev, and Siegel as a cross-check, and record the formal scaling-relevance exponent $s^*(a) = 1/c_l(a)$, below which fractional dissipation is asymptotically subdominant in self-similar variables for fixed sufficiently regular data. The contribution is the realization-dependent spectral picture of the collapse profile itself.
toXiv_bot_toot
@kexpmusicbot@mastodonapp.uk2026-06-21 06:59:20
@thomasfuchs@hachyderm.io2026-06-15 13:37:48
Kodak DC120 (kind of 1MP*, 1997)
*The camera has an extremely odd sensor size of 850x984 (non-square pixels??!), and only RawTherapee (open source photo editing app) opened it up in the full stored resolution of 840x968 (sensors usually have a few more pixels than the highest resolution a camera can store, it's complicated).
I converted to TIFF and stretched in Photoshop to proper aspect ratio; then edited with CameraRaw.
#ShittyCameraChallenge
