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Golden dark sirens - exceptionally well-localized gravitational-wave (GW) sources without electromagnetic counterparts - offer a powerful route to precision measurements of the Hubble constant, $H_0$, with next-generation (XG) detectors. The statistical promise of this method, however, places stringent demands on waveform accuracy and detector calibration, as even small systematic errors can dominate over statistical uncertainties at high signal-to-noise ratios. We investigate the impact of waveform-modeling systematics on golden dark siren cosmology using a synthetic population of binary black holes consistent with current GW observations and analyzed in the XG-detector era. By comparing state-of-the-art waveform models against numerical-relativity-based reference signals, we quantify modeling inaccuracies from both modeling and data-analysis perspectives and assess how they propagate into biases in luminosity distance, host-galaxy association, and single-event $H_0$ inference. We find that while current waveform models often allow recovery of statistically consistent $H_0$ posteriors, small waveform-induced biases can significantly affect three-dimensional localization and host g

Silver phenylselenide (AgSePh), known as mithrene, is a two-dimensional (2D) organic-inorganic chalcogenide (MOC) semiconductor with a wide direct band gap, narrow blue emission and in-plane anisotropy. However, its application in next-generation optoelectronics is limited by crystal size and orientation, as well as challenges in large-area growth. Here, we introduce a controlled tarnishing step on the silver surface prior to the solid-vapor-phase chemical transformation into AgSePh thin films. Mithrene thin films were prepared through thermally assisted conversion (TAC) at 100°C, incorporating a pre-tarnishing water (H${_2}$O) vapor pulse and propylamine (PrNH${_2}$) as a coordinating ligand to modulate Ag${^+}$ ion reactivity and facilitate the conversion of Ph${_2}$Se${_2}$ into an active intermediate. The AgSePh thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and grazing incidence wide-angle X-ray scattering (GIWAXS). The pre-tarnishing process, combined with organic ligands, resulted in large crystals exceeding 1 $μ$m and improved homogeneous in-plane orientation, while also enabling the selective, wafer-scale synthesis of mithrene

Metal-organic chalcogenides (MOCs), robust crystalline assemblies composed of coinage metals, chalcogens and organic ligands, are typically synthesized via prolonged, high temperature tarnishing of vacuum-deposited metal films with organochalcogen precursors. The prolonged exposure to high temperatures and the necessity for direct vacuum deposition of silver can induce damage to the underlying films, posing significant challenges to the fabrication of optoelectronic devices, despite their cost-effectiveness and chemical robustness. This study introduces vapor-assisted solution processing, a novel chemical vapor deposition method, enabling remarkably rapid fabrication of luminescent MOC films. Furthermore, the first MOC-based light-emitting diodes (MOCLEDs) are realized, achieving an external quantum efficiency (EQE) approaching 0.1% and electroluminescence peaking at 633 nm. These results highlight the potential of MOCs as next-generation emitters for displays and solid-state lighting. This work offers a promising fabrication strategy and insights for advancing MOCLEDs and expanding their optoelectronic potential.

Recently, a distinct form of online antisocial behavior, known as "fanchuan", has emerged across online platforms, particularly in livestreaming chats. Fanchuan is an indirect attack on a specific entity, such as a celebrity, video game, or brand. It entails two main actions: (i) individuals first feign support for the entity, and exhibit this allegiance widely; (ii) they then engage in offensive or irritating behavior, attempting to undermine the entity by association. This deceptive conduct is designed to tarnish the reputation of the target and/or its fan community. Fanchuan is a novel, covert and indirect form of social attack, occurring outside the targeted community (often in a similar or broader community), with strategic long-term objectives. This distinguishes fanchuan from other types of antisocial behavior and presents significant new challenges in moderation. We argue it is crucial to understand and combat this new malicious behavior. Therefore, we conduct the first empirical study on fanchuan behavior in livestreaming chats, focusing on Bilibili, a leading livestreaming platform in China. Our dataset covers 2.7 million livestreaming sessions on Bilibili, featuring 3.6

Deep learning constitutes a pivotal component within the realm of machine learning, offering remarkable capabilities in tasks ranging from image recognition to natural language processing. However, this very strength also renders deep learning models susceptible to adversarial examples, a phenomenon pervasive across a diverse array of applications. These adversarial examples are characterized by subtle perturbations artfully injected into clean images or videos, thereby causing deep learning algorithms to misclassify or produce erroneous outputs. This susceptibility extends beyond the confines of digital domains, as adversarial examples can also be strategically designed to target human cognition, leading to the creation of deceptive media, such as deepfakes. Deepfakes, in particular, have emerged as a potent tool to manipulate public opinion and tarnish the reputations of public figures, underscoring the urgent need to address the security and ethical implications associated with adversarial examples. This article delves into the multifaceted world of adversarial examples, elucidating the underlying principles behind their capacity to deceive deep learning algorithms. We explore t

The optical response of metal nanoparticles is governed by plasmonic resonances, which are dictated by the particle morphology. A thorough understanding of the link between morphology and optical response requires quantitatively measuring optical and structural properties of the same particle. Here we present such a study, correlating electron tomography and optical micro-spectroscopy. The optical measurements determine the scattering and absorption cross-section spectra in absolute units, and electron tomography determines the 3D morphology. Numerical simulations of the spectra for the individual particle geometry, and the specific optical setup used, allow for a quantitative comparison including the cross-section magnitude. Silver nanoparticles produced by photochemically driven colloidal synthesis, including decahedra, tetrahedra and bi-tetrahedra are investigated. A mismatch of measured and simulated spectra is found when assuming pure silver particles, which is resolved by the presence of a few atomic layers of tarnish on the surface, not evident in electron tomography. The presented method tightens the link between particle morphology and optical response, supporting the pred

Cargo loss/damage is a very common problem faced by almost any business with a supply chain arm, leading to major problems like revenue loss and reputation tarnishing. This problem can be solved by employing an asset and impact tracking solution. This would be more practical and effective for high-cost cargo in comparison to low-cost cargo due to the high costs associated with the sensors and overall solution. In this study, we propose a low-cost solution architecture that is scalable, user-friendly, easy to adopt and is viable for a large range of cargo and logistics systems. Taking inspiration from a real-life use case we solved for a client, we also provide insights into the architecture as well as the design decisions that make this a reality.

Two newly confirmed "super-puff" planets are so diffuse that they are less dense than cotton candy, despite being about the size of Jupiter。 Their rare orbital relationship and enormous, lightweight atmospheres could provide valuable clues about how some of the strangest planets in the galaxy come to exist

A new study suggests Earth may have been sending tiny hitchhikers to Venus for billions of years。 Researchers found that asteroid impacts could launch microbes into space, where some might survive the journey and end up suspended in Venus' clouds。 If future missions detect life there, there's a surprising chance it didn't originate on Venus at all—

Researchers have created an AI-based simulation that makes it much faster to model how neutron star mergers produce many of the universe's heaviest elements。 The new tool could improve predictions of these powerful explosions while helping scientists better connect observations in space with experiments on Earth

Ultra-fine bubbles may offer a cleaner way to perfect inkjet printing for next-generation electronics。 By simply changing the number of bubbles in each droplet, researchers were able to dramatically reshape the final printed pattern without leaving behind unwanted chemical residues

Researchers have achieved a major milestone by creating a long-sought two-dimensional quantum material and confirming its unusual conducting edge states。 The ability to control these states through strain could make the material a promising platform for future room-temperature quantum electronics

Researchers have created quantum control techniques that can make a system appear to run backward in time。 By precisely managing quantum measurements, they can reshape the system's arrow of time and even harvest energy from the measurement process itself。 The breakthrough could lead to more powerful quantum computers, quantum batteries, and other a

Researchers discovered that electricity can dramatically reshape how heat flows through certain ceramic materials, increasing heat conduction by almost threefold in a preferred direction。 The unexpected result could lead to much more efficient cooling technologies and energy-saving devices

A strange "chirping" signal from a distant supernova has revealed the birth of a magnetar, confirming that these incredibly magnetic neutron stars can power the universe's brightest stellar explosions。 The discovery also marks the first time Einstein's general relativity has been used to explain the mechanics of a supernova

Researchers have proposed that black holes stop evaporating at the last moment, leaving behind tiny remnants that preserve all the information they contain。 The same seven-dimensional geometry behind this idea could also help explain why elementary particles have mass

A new quantum theory bridges two rival models of how impurities behave inside many-particle systems, resolving a problem that has challenged physicists for decades。 The findings could reshape experiments on ultracold atoms, semiconductors, and other exotic forms of quantum matter

Physicists have developed a new optical centrifuge that can precisely spin molecules inside a superfluid for the first time。 The advance could help unravel some of the biggest mysteries of quantum liquids and reveal how superfluidity breaks down at the atomic scale

It's unclear how the planet avoided its star's bloated red giant stage