Large AI model training data sets often require a significant amount of human labor to annotate and/or format prior to model training. Researchers recently wrote a review paper highlighting self-supervised learning methods for 3D pre-training and provide a unified perspective on comparison and prediction techniques.

Researchers discovered a previously unknown polishing mechanism in bismuth, a promising layered material for future computer chips. Instead of being scratched or chemically pulled away during chemical mechanical polishing, bismuth forms a thin oxide layer that slips sideways, enabling unusually rapid material removal. The findings contribute to future advances in semiconductor manufacturing.

In the fields of material science and engineering, understanding the principles of wear and friction is pivotal for the development and optimization of materials and mechanical systems. A research team has synthesized the current research on wear modeling and friction-induced noises, exploring their mechanisms, influencing factors, and predictive challenges.  By studying wear modeling and friction-induced noise, engineers are better able to predict the lifespans of components and prevent structural failure across a wide range of industries.

A patient-derived KDF1 mutation was found to impair enamel formation by disrupting cell adhesion and Hippo-YAP signaling in dental epithelial cells. Using genetically engineered mice and cellular models, the scientists showed that the mutation weakened intercellular connections, increased abnormal YAP activity, and blocked proper ameloblast differentiation. Treatment with a YAP-TEAD1 inhibitor partially restored enamel-forming functions. The findings reveal a new disease mechanism underlying amelogenesis imperfecta and suggest potential therapeutic strategies for patients.

As humanity's exploration of the Earth's internal structure deepens, Earth's free oscillations, serving as crucial "fingerprints" for revealing the large-scale structure and dynamic processes within the Earth, have always been a core subject in geophysics. Ground-based station observations are currently the mainstream method for measuring Earth's free oscillations. With the advancement of space technology, high-precision inter-satellite distance measurement holds the potential to become a novel method for detecting these oscillations.

The rapid increase in space debris poses a significant threat to the safety of in-orbit spacecraft and the utilization of valuable orbital resources. Active debris removal (ADR) has emerged as the most effective approach to mitigating debris growth. However, traditional rigid capture methods are limited by constraints such as capture distance, target adaptability, and the risk of generating secondary debris, making them inadequate for the increasingly complex space debris environment. Net-membrane capture systems integrate smart materials with controllable deployment mechanisms, offering advantages such as long-range capture, adaptability to non-cooperative targets, and reusability. However, the dynamic characteristics throughout the entire process—shooting, deployment, contact, and wrapping capture—remain insufficiently understood. The combined stretching, shearing, and bending deformations of the membrane, along with the complex contact mechanics introduced by debris spin, pose challenges for traditional modeling approaches such as the finite element method (FEM) and the absolute nodal coordinate formulation (ANCF).

Space-based distributed array telescope formations, through multi-telescope collaborative observation and long-baseline optical interferometry, can significantly enhance deep space exploration capabilities, providing key technological support for missions such as asteroid monitoring and the search for extraterrestrial life. However, the measurement and control performance of such formations is highly dependent on the precision of intertelescope baseline measurements. Frequency-sweeping interferometry (FSI) technology, with its significant advantages—including freedom from the ambiguity range limitation, capability for non-cooperative target measurement, strong anti-interference ability in complex space environments, and high maturity of core components—has emerged as the most promising technical approach for baseline measurement in space-based distributed array telescope formations. Nevertheless, advancing this technology toward aerospace engineering applications still faces two major challenges: suppressing optical frequency-sweep nonlinearity and eliminating dynamic ranging errors. Currently, using electro-optic modulation to generate highly linear, synchronized, symmetrically sweeping positive and negative sidebands—establishing a frequency-sweeping interferometry system based on electro-optic sideband modulation—represents an effective method to address the issues of sweep nonlinearity and Doppler dynamic error. However, frequency-sweeping interferometry systems based on electro-optic sideband modulation lack a traceable on-orbit optical frequency-sweep reference, making it difficult to ensure long-term stable measurement and accuracy maintenance on orbit. Therefore, further research into high-precision electro-optic sideband modulation-based frequency-sweeping interferometry methods with traceable sweep references is of great significance for advancing the development of baseline measurement technology for space-based distributed array telescope formations.

Spaceborne gravitational wave detectors achieve long-baseline inter-satellite laser interferometry through satellite constellations, overcoming the limitations imposed by seismic noise and interferometer arm lengths on ground-based detectors, and providing a new observational means for detecting medium- and low-frequency gravitational waves and revealing the origin and evolution of the universe. The TianQin project aims to build a high‑precision spaceborne gravitational wave detection array. The test mass within its core component, the gravitational reference sensor, must transition smoothly from a high-load locked state to an ultra‑quiet and ultra‑stable geodesic state after launch and orbit injection, and this release process is a critical link for mission success. However, the plunger of the grabbing, positioning, and release mechanism (GPRM), under prolonged high-load operation, induces adhesion effects such as cold welding on the test mass, and the available electrostatic capture force is insufficient to overcome the interfacial adhesion, making it difficult for conventional release strategies to meet the strict constraint of residual velocity below 5 μm/s. Therefore, establishing a theoretical model that can accurately describe the dynamic behavior of the release mechanism and the interfacial adhesion effect is of great significance for evaluating release performance, revealing the mechanism of residual velocity generation, and guiding the optimization of mechanism parameters.

Ionic thermoelectrics (i-TEs) convert temperature differences into electricity, taking forms from liquids and gels to polyelectrolytes and porous solids. A new review in National Science Review takes a bird's-eye view—from the physics and chemistry of a single electrolyte to the engineering of commercial products—and lays out a material–device–system design framework. The authors conclude that reaching commercial products demands concerted, cross-disciplinary efforts in standardization, scalable manufacturing, reliability, and sustainability—not merely ever-higher performance metrics.

Near‑Earth asteroid impacts pose a major threat that could lead to the destruction of human civilization, having already caused catastrophic environmental changes and mass extinctions multiple times in history. In recent years, asteroids with diameters ranging from tens to hundreds of meters have frequently made close flybys of Earth, and a large number of large‑sized asteroids remain undiscovered, with warning times often only a few days to weeks. For large‑sized asteroids exceeding 100 meters in diameter, or even kilometer‑scale ones, traditional kinetic impact or long‑term force deflection methods offer limited energy and cannot achieve effective deflection within short timeframes. Using the enormous energy generated by nuclear detonation to directly destroy or rapidly deflect the asteroid's orbit is the most effective, and in extreme cases the only feasible, approach for dealing with large asteroids or those with short warning times. However, existing research on detonation defense has mostly focused on the direct rendezvous impact mode, in which the impact and detonation positions cannot be autonomously selected and energy coupling is relatively weak. Moreover, there is a lack of systematic analysis of the capability coverage and overall effectiveness of different defense modes, severely constraining the optimization of engineering designs.