Ice nucleation is greatly important in areas as diverse as climate change, cryobiology, geology or food industry. Predicting the ability of a substrate to induce the nucleation of ice from supercooled water is a difficult problem. Here, we use molecular simulations to analyse how the ice nucleating ability is affected by the substrate lattice structure and orientation. We focus on different model lattices: simple cubic, body centred cubic and face centred cubic, and assess their ability to induce ice nucleation by calculating nucleation rates. Several orientations are studied for the case of the face centred cubic lattice. Curiously, a hexagonal symmetry does not guarantee a better ice nucleating ability. By comparing the body centred cubic and the cubic lattices we determined that there is a significant role of the underlying crystal plane(s) on ice nucleation. The structure of the liquid layer adjacent to the substrate reveals that more efficient nucleants induce a more structured liquid. The most efficient substrates present a strong sensitivity of their ice nucleating ability to the lattice parameters. Introducing a novel methodological approach, we use Classical Nucleation The
Cryosurgery employs a safe and relatively simple technique of exposure and is an advantageous and highly rated method. For its effective application, it is necessary to control both the volume of the expanding freezing zone and volumetric thermal field dynamics. The aim of this study was to perform a thermal imaging study of freezing and thawing in a model system (gel phantom) to predict the dynamics of the freezing zone during cryodestruction of biological tissues in vivo. Here, the thermal imager is an effective tool for demonstrating the surface temperature distribution. We have studied how the observed infrared image relates to the distribution and change of the thermal field in depth. For this purpose, we created test measuring equipment for simultaneous analysis of the dynamics of thermal fields on the surface, video recording of freezing and thawing on the surface as well as in the depth of the gel phantom, measuring the temperature at any given point in the depth and modeling in the zone of low-temperature exposure of vessels with different blood flow parameters. It was revealed that with a modeled vessel in the low-temperature exposure zone, the surface thermal fields defo
Biostasis has the potential to extend human lives by offering a bridge to powerful life extension technologies that may be developed in the future. However, key questions in the field remain unresolved, including which biomarkers reliably indicate successful preservation, what technical obstacles pose the greatest barriers, and whether different proposed revival methods are theoretically feasible. To address these gaps, we conducted a collaborative forecasting exercise with 22 practitioners in biostasis, including individuals with expertise in neuroscience, cryobiology, and clinical care. Our results reveal substantial consensus in some areas, for example that synaptic connectivity can serve as a reliable surrogate biomarker for information preservation quality. Practitioners identified three most likely failure modes in contemporary biostasis: inadequate preservation quality even under ideal conditions, geographic barriers preventing timely preservation, and poor procedural execution. Regarding revival strategies, most respondents believe that provably reversible cryopreservation of whole mammalian organisms is most likely decades away, with provably reversible human cryopreservat
Ice nucleation and growth are critical in many fields, including atmospheric science, cryobiology, and aviation. However, understanding the detailed mechanisms of ice crystal growth remains challenging. In this work, crystallization at the ice/quasi-liquid layer (QLL) interface of the basal and primary prism (prism1) surfaces of hexagonal ice (Ih) was investigated using molecular dynamics simulations across a wide range of temperatures for the TIP4P/Ice model, with comparisons to the mW coarse-grained model. Together with elucidating the temperature-dependent mechanisms of crystallization, face-specific growth rates were systematically estimated. While the prism surface generally exhibits faster growth rates than the basal surface, a temperature-dependent crossover in growth rates between the basal and prism surfaces is observed in TIP4P/Ice simulations, which correlates with crossovers in QLL thickness and properties and with the well-known column to platelets transition in ice-crystal habits at low vapor pressure. This observation helps decode the complex dependence between crystal morphology and temperature in ice crystals.
Vitrification is a promising approach for ice-free cryopreservation of biological material, but progress is hindered by the limited set of experimental tools for studying processes in the interior of the vitrified matter. Isochoric cryopreservation chambers are often metallic, and their opacity prevents direct visual observation. In this study, we introduce photon counting X-ray computed tomography (CT) to compare the effects of rigid isochoric and unconfined isobaric conditions on vitrification and ice formation during cooling of two aqueous solutions: 50 wt% DMSO and a coral vitrification solution, CVS1. Previous studies have only compared vitrification in isochoric systems with isobaric systems that have an exposed air-liquid interface. We use a movable piston to replicate the surface and thermal boundary conditions of the isochoric system yet maintain isobaric conditions. When controlling for the boundary conditions we find that similar ice and vapor volume fractions form during cooling in isochoric and isobaric conditions. Interestingly, we observe distinct ice and vapor cavity morphology in the isochoric systems, possibly due to vapor outgassing or cavitation as rapid cooling
The freezing of colloidal suspensions is encountered in many natural and engineering processes such as the freezing of soils, food engineering, and cryobiology. It can also be used as a bio-inspired, versatile, and environmentally-friendly processing route for porous materials and composites. Yet, it is still a puzzling phenomenon with many unexplained features, due to the complexity of the system and the space and time scales at which the process should be investigated. We demonstrate here the interest of fast X-ray computed tomography to provide time-lapse, three-dimensional, in situ imaging of ice crystal growth in a colloidal silica suspension. The experimental measurements show that the local increase of colloid concentration does not affect the growth kinetics of the crystals, until the colloidal particles become closely packed. For particles much smaller than ice crystals, the concentrated colloidal suspension is equivalent to a simple liquid phase with higher viscosity and a freezing point determined by the concentration of colloidal particles.
A new sunlight-powered material can convert visible light into higher-energy UV light, overcoming a challenge that has frustrated scientists for years。 The breakthrough could enable cleaner air purification, solar-driven chemistry, and advanced manufacturing technologies using nothing more than natural sunlight
Plex is pushing customers to newer features and more frequent payments
Biology could explain the find, but there are other potential explanations
The discovery underscores the increased effort being poured into Mac infostealers
The EU went after Google for the practice of bundling its search engine and browser with Android
A new AI-powered framework could transform how astronomers measure the expansion of the Universe。 By analyzing images of Type Ia supernovae and modeling their environments in unprecedented detail, researchers can estimate cosmic distances with near-spectroscopic accuracy。 The technique is designed for the flood of data expected from the upcoming Ve
Disturbances in this critical sense are often linked to problems with brain health
It’s a pretty good movie, but it needed to be a great movie to thrive in an oversaturated superhero market
It's difficult to pinpoint the moment in my life where America started to lose the plot
A major breakthrough in quantum technology has turned magnons, tiny magnetic waves once considered too short-lived for practical use, into promising carriers of quantum information。 Researchers extended their lifetime by nearly 100 times, reaching up to 18 microseconds, and discovered that the main limitation is not a law of physics but the purity
A rare meteorite has revealed evidence of a massive lost world that once orbited the young Sun before being destroyed in a catastrophic collision。 The discovery suggests some early planets formed from dramatically different materials than Earth and Mars, rewriting part of the solar system’s origin story
The race to build data centers in space is gaining momentum as AI drives unprecedented demand for computing power。 Orbital facilities could tap into abundant solar energy and avoid many of the environmental challenges faced on Earth。 Yet space remains a harsh and expensive place to operate, with major hurdles including cooling, maintenance, radiati
A newly proposed quantum sensing technique could make it much easier to identify one of physics’ newest and most intriguing classes of magnets: altermagnets。 These unusual materials, discovered only a few years ago, appear to combine the speed and efficiency of antiferromagnets with some of the useful electronic properties of traditional magnets, m
I have not seen anyone put out a date for a new rocket, and actually hit it