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The Laude Institute, a nonprofit that runs the K Prize multi-round AI coding challenge, says a Brazilian prompt engineer won with just 7.5% of the right answers (Russell Brandom/TechCrunch)
https://techcrunch.com/2025/07/23/a-ne

A new AI coding challenge just published its first results – and they aren’t pretty | TechCrunch
A new AI coding challenge has revealed its first winner — and set a new bar for AI-powered software engineers.  On Wednesday at 5pm PST, the

This https://arxiv.org/abs/2504.10928 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Radiative-transfer models for dusty Type II supernovae
Dust is expected to form on a year timescale in core-collapse supernova (SN) ejecta. Its existence is revealed through an infrared brightening, an optical dimming, or a blue-red emission-line profile asymmetry. To investigate how the dust location and amount impact observations, we computed ultraviolet-to-optical spectra of interacting and standard, noninteracting Type II SNe using state-of-the-art models -- for simplicity we adopted 0.1micron silicate grains. These models account for the full …

Outflows from Star-Forming Galaxies in the Early Universe: Evolution from Double- to Single-Peaked Lyman-$ \alpha $ Profiles Following Delayed Supernova Feedback
James Nianias, Jeremy Lim, Yik Lok Wong, Gordon Wong
https://arxiv.org/abs/2506.20422

Outflows from Star-Forming Galaxies in the Early Universe: Evolution from Double- to Single-Peaked Lyman-$ α$ Profiles Following Delayed Supernova Feedback
Lyman-$ α$ emission, which owing to its resonant nature strongly couples the emergent line profile to gas kinematics, has become a key observable for probing outflows from star-forming galaxies in the early universe. Typically, Lyman-$ α$ profiles are explained in terms of idealised expanding shell models, while empirically-motivated interpretations of Lyman-$ α$ profiles that make use of comparisons with kinematics revealed by other spectral features (e.g. metal emission and absorption line…

A Study in Thermal: Advantage framework for resource engines
Jakub Czartowski, Rafa{\l} Bistro\'n
https://arxiv.org/abs/2507.05699 https://

A Study in Thermal: Advantage framework for resource engines
Thermal engines have been one of the principal topics of thermodynamics ever since its beginning. Today, in the era of the second quantum revolution, although the thermal processes in constant temperatures are relatively well understood in the language of resource theories, a framework to describe thermal engines is still in its infancy. In this work we formalize the resource theory of engines, initially put forward in [Quantum 8, 1222], and define such quantities as engine efficiency. Then, we…

"For the first time, we architected every part of the rack as a unified system," Su explained, highlighting Helios as "really a rack that functions like a single, massive compute engine."
http://m.timesofindia.com/articleshow/121834703.cms
Why does th…

AMD unveils next-gen AI chips as it takes on Nvidia: 'For the first time, we...' CEO Lisa Su says - The Times of India
Tech News : AMD has revealed its Instinct MI400 series AI chips, designed for rack-scale systems and set to compete with Nvidia's Blackwell. CEO Lisa Su highlight

Probing the sensitivity of CTAO-N LSTs observations at large zenith angles to the multi-TeV gamma-ray emission from the inner 10 parsecs of the Galactic Center
Shotaro Abe, Tomohiro Inada, Emmanuel Moulin
https://arxiv.org/abs/2506.04074

Probing the sensitivity of CTAO-N LSTs observations at large zenith angles to the multi-TeV gamma-ray emission from the inner 10 parsecs of the Galactic Center
Observations of the Galactic Center using Imaging Atmospheric Cherenkov Telescopes (IACTs), such as H.E.S.S., MAGIC, and VERITAS, have revealed a very-high-energy (VHE, $\gtrsim 100$ GeV) gamma-ray source, HESS J1745$-$290, aligned with the dynamical center of the Milky Way. This source shows point-like emission ($\lesssim 0.1^\circ$) and a strong suppression in its energy-differential spectrum in the ten TeV energy regime, modeled well by a power-law with an exponential cutoff. The origin of t…

RNA Dynamics and Interactions Revealed through Atomistic Simulations
Olivier Languin-Catto\"en, Giovanni Bussi
https://arxiv.org/abs/2507.08474 https:…

RNA Dynamics and Interactions Revealed through Atomistic Simulations
RNA function is deeply intertwined with its conformational dynamics. In this review, we survey recent advances in the use of atomistic molecular dynamics simulations to characterize RNA dynamics in diverse contexts, including isolated molecules and complexes with ions, small molecules, or proteins. We highlight how enhanced sampling techniques and integrative approaches can improve both the precision and accuracy of the resulting structural ensembles. Finally, we examine the emerging role of ar…

Constraints on Quaoar's rings and atmosphere from JWST/NIRCam observations of a stellar occultation
Benjamin Proudfoot, Bryan Holler, Ko Arimatsu, Flavia Rommel, Cameron Collyer, Estela Fern\'andez-Valenzuela
https://arxiv.org/abs/2506.07898

Constraints on Quaoar's rings and atmosphere from JWST/NIRCam observations of a stellar occultation
Observations of stellar occultations have revealed that small bodies are capable of hosting ring systems. The trans-Neptunian object (TNO) Quaoar, is the host of an enigmatic ring system, with two rings located well-outside the Roche limit. To better understand these structures, we observed a stellar occultation by Quaoar and its rings using the James Webb Space Telescope's (JWST) NIRCam instrument. Our observations detect both known rings, although Q2R -- the inner known ring -- is not detecte…

Stephenson 2 DFK 52: Discovery of an exotic red supergiant in the massive stellar cluster RSGC2
Mark A. Siebert, Elvire De Beck, Guillermo Quintana-Lacaci, Wouter Vlemmings
https://arxiv.org/abs/2507.11609

Stephenson 2 DFK 52: Discovery of an exotic red supergiant in the massive stellar cluster RSGC2
Atacama Large Millimeter/submillimeter Array (ALMA) observations at 1.3mm have recently revealed surprising complexity in the circumstellar environment of DFK 52, a red supergiant (RSG) located in the Stephenson 2 massive open cluster. We provide an initial characterisation of the star's mass-loss properties by studying its circumstellar emission in continuum, $^{12}$CO, $^{13}$CO, and SiO rotational lines. We find that DFK 52 is surrounded by an extremely large outflow (up to 50,000 au in radi…

Insights into Ionic Diffusion in C-S-H Gel Pore from MD Simulations: Spatial Distributions, Energy Barriers, and Structural Descriptor
Weiqiang Chen, Kai Gong
https://arxiv.org/abs/2506.23089

Insights into Ionic Diffusion in C-S-H Gel Pore from MD Simulations: Spatial Distributions, Energy Barriers, and Structural Descriptor
Understanding transport behavior in nanoconfined environments is critical to many natural and engineering systems, including cementitious materials, yet its molecular-level mechanisms remain poorly understood. Here, molecular dynamics (MD) simulations were used to investigate Na+, Cl-, and water diffusion inside a 4 nm calcium-silicate-hydrate (C-S-H) pore channel over temperatures ranging from 300 K to 360 K. Spatially resolved analysis revealed strong suppression of diffusivity near the solid…