Tootfinder

Trump’s fragile agreement with Iran has introduced a new variable into this year’s midterm elections.
Democratic candidates have assailed the agreement,
arguing that the president accepted unfavorable terms to try to end an unnecessary war that hurt the economy.
Republicans have been more divided.
Some, eager to turn the page on the unpopular war, are hailing falling gas prices and praising Trump for weakening Iran’s military capabilities,
while others are expr…

How Trump’s Fragile Agreement With Iran Is Shaping the Midterms
Democrats say the president started an economically painful war that resulted in nothing positive. Republicans are more divided, even as they show some signs of relief at falling gas prices.

Feeling very honored to be nominated for the Hedy Lamarr Preis 2026 next to all these other great researchers 🙏
https://www.wienholding.at/news/7-forscherinnen-fuer-hedy-lamarr-preis-der-stadt-wien-nominiert

Mit der Studie ergibt vieles wieder Sinn, wenn davon gesprochen wird, dass »die Politik«™ Sorgen ernst nehmen müsse – die Sorgen sind nämlich rassistischer Natur und weniger Abstiegsängste. Passt auch zum Sachsen-Anhalt-Monitor 2025, demzufolge 90 Prozent mit ihrem Leben zufrieden sind. Nur die Ausländer, Schmarozer und Queers stört den Deutschen.

Price Responses of Rwandan Tungsten Exports under Conflict Minerals Regulation
Haruka Nagamori, Kazuhiko Nishimura
https://arxiv.org/abs/2608.08690 https://arxiv.org/pdf/2608.08690 https://arxiv.org/html/2608.08690
arXiv:2608.08690v1 Announce Type: new
Abstract: Section 1502 of the Dodd--Frank Act, enacted in 2010, requires U.S.-listed companies using tin, tantalum, tungsten, and gold (3TG) from the Democratic Republic of the Congo and adjoining countries to disclose information on the minerals' origins. Concerns have been raised that the regulation may have induced a de facto embargo through avoidance of sourcing from the covered region. However, how the price responsiveness of mineral exports evolved under changing institutional and market conditions remains insufficiently understood. Since tungsten production in the covered region is concentrated almost entirely in Rwanda, this study examines the price responsiveness of Rwandan tungsten exports from January 2009 to December 2023.
Because missing export quantity data prevent continuous observation of export unit values, we apply the identification approach of Nakano and Nishimura (2025), combining monthly mirror trade data from UN Comtrade with exchange rates and a world average price. An importer fixed-effects model is estimated using export value as the dependent variable, with the sample divided into four periods according to changes in the institutional and market environment.
The results reveal substantial temporal variation in price responsiveness. A statistically significant negative price response is observed in Period 1 ($\eta=-20.814$, $p<0.01$), disappears in Period 2 ($\eta=1.814$, $p>0.10$), reappears in Period 3 ($\eta=-5.277$, $p<0.01$), and disappears again in Period 4 ($\eta=0.440$, $p>0.10$). Coefficient-difference tests confirm significant changes between Periods 1 and 2 ($p=0.0021$) and between Periods 3 and 4 ($p=0.0006$). These findings suggest that the price responsiveness of Rwandan tungsten exports varied substantially over time rather than following a uniform trajectory after the regulation.
toXiv_bot_toot

Deformation algorithm: Deforming (2 1)-dimensional integrable systems to higher dimensional ones
Wang Fa-Ren, Jia Man, Lou S Y
https://arxiv.org/abs/2608.01293 https://arxiv.org/pdf/2608.01293 https://arxiv.org/html/2608.01293
arXiv:2608.01293v1 Announce Type: new
Abstract: The deformation algorithm based on conservation laws can lift (1 1)-dimensional integrable systems to higher-dimensional counterparts while preserving Lax integrability, yet its generalization to (2 1)-dimensional models has remained an open problem. This paper establishes a unified deformation framework for two (2 1)-dimensional integrable equations: the anisotropic Kadomtsev-Petviashvili (KP) equation and the isotropic Nizhnik-Novikov-Veselov (NNV) equation. By introducing a set of mutually commuting field-dependent deformation operators, we systematically construct infinite families of ($m 3$)-dimensional integrable KP and NNV hierarchies, derive their closed-form Lax pairs, and rigorously verify integrability via the vanishing commutator condition of Lax operators. For each high-dimensional hierarchy, concrete finite-dimensional master systems are obtained by truncating auxiliary spatial variables: a (3 1)-dimensional KP system and a (4 1)-dimensional generalized NNV system. Further symmetry reductions recover the original (2 1)-dimensional KP and NNV equations, and more importantly produce two distinct Harry-Dym (HD)-type reciprocal integrable systems. The KP reduction yields an anisotropic (2 1)-dimensional HD model, while the NNV reduction generates the first spatially isotropic two-space-dimensional HD system reported so far, filling a notable gap in existing literature. Parallel comparison of the KP and NNV branches reveals that the spatial symmetry of the original two-dimensional parent equation directly governs the symmetry properties of its high-dimensional deformations and HD dual subsystems. Our work not only extends the conservation-law deformation conjecture beyond (1 1)-dimensions to accommodate both strong Lax and weak Lax structures, but also provides a universal route to construct reciprocal links for multi-dimensional integrable systems.
toXiv_bot_toot

Theoretical derivation of blood velocity from TOF-MRA based artery centerline
Abrar Faiyaz
https://arxiv.org/abs/2607.16498 https://arxiv.org/pdf/2607.16498 https://arxiv.org/html/2607.16498
arXiv:2607.16498v1 Announce Type: new
Abstract: Time-of-flight magnetic resonance angiography (TOF-MRA) is widely used for structural vascular imaging, but extracting functional hemodynamics like blood velocity typically requires supplementary phase-contrast scans. This study proposes a novel, physics-informed computational framework to extract variable fluid velocity directly from standard TOF-MRA signal profiles. We analytically expand the Bloch equations into Bloch-McConnell flow equations, establishing a mathematical relationship between the spatial decay of longitudinal magnetization and fluid velocity. To validate this derivation and overcome the limitations of constant-velocity assumptions, a MATLAB simulation framework was developed to model fluid flow in two variable-geometry flowing tube cases i.e continuous tapering and focal stenosis -under synthetic scanner noise. A global inverse optimization approach utilizing Dual-Tikhonov regularization was deployed to stably invert the ill-posed transit time integral, actively penalizing high-frequency numerical ringing while preserving structural curve stiffness. The computational sim-ulations successfully recovered ground-truth point-wise velocities, accurately tracking gradual hemodynamic accelerations and sharp stenotic jets. This theoretical framework provides a robust mathematical proof-of-concept that quantitative, localized functional hemodynamic metrics can be extracted from standard structural MRA imaging, estab-lishing a foundation for advanced flow quantification without requiring additional scan time.
toXiv_bot_toot