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The disruption of protein structures by denaturants like urea is well studied, though its molecular mechanisms remain unclear. Using Molecular Dynamics (MD) simulations, we investigated how urea affects the structural stability of Bovine Serum Albumin (BSA) at concentrations from 0 M to 5 M. Our results reveal that urea induces a dehydration/rehydration cycle, characterized by displacement and partial replacement of water molecules in BSAs hydration shell. At low concentrations, urea reduces protein/water hydrogen bonds while enhancing protein-urea interactions. At higher concentrations, urea aggregation limits these interactions, promoting rehydration and changes in tertiary structure, while secondary structure remains largely intact. These findings provide insights into the mechanisms of protein denaturation and stability by urea.
Breast cancer is the most common type of cancer observed in women. Communication with the tumor microenvironment allows invading breast cancer cells, such as triple negative breast cancer cells, to adapt to specific substrates. The substrate topography modulates the cellular behavior, among other factors. A number of different materials and micro/nanofabrication techniques have been employed to develop substrates for cell culturing. Silicon-based substrates present a lot of advantages as they are amenable to a wide range of processing techniques and they permit rigorous control over the surface structure. We investigate and compare the response of triple negative breast cancer cells (MDA-MB-231) on laser-patterned silicon substrates with two different topographical scales, i.e., the micro- and the nanoscale, in the absence of any other biochemical modification. We develop silicon surfaces with distinct morphological characteristics by employing two laser systems with different pulse durations (nanosecond and femtosecond) and different processing environments (vacuum, SF6 gas, and water). Our findings demonstrate that surfaces with micro-topography are repellent, while surfaces with
Quantum mechanics has journeyed from a strange and controversial idea to the foundation of some of humanity’s most advanced technologies。 Now researchers are pushing its boundaries even further, with potential breakthroughs in energy, medicine, computing, and our understanding of the universe
Broadcom accuses Allstate of dodging VMware audits
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
Hubble has captured a spectacular view of LH 95, where about 2,500 young stars are still on their journey to becoming full-fledged stars。 Scientists discovered these growing stars can keep pulling in gas and dust for millions of years, extending an important stage of stellar development。 The region also contains multiple generations of stars living
Scientists have combined machine learning with quantum physics to discover two new superconductors and create a much faster way to search for many more。 The technique could bring researchers significantly closer to the long-sought goal of a room-temperature superconductor
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
What if consciousness isn’t limited to brains like ours。 Philosophers Eric Schwitzgebel and Jeremy Pober argue that consciousness could arise in many different forms of life, even in beings built from radically different materials than those found on Earth。 Drawing on the vastness of the universe and the likely existence of countless alien civiliza
Scientists are calling for a lunar quarantine facility where samples from Mars, the Moon, and beyond would be examined before being brought to Earth。 They warn that even a tiny alien microorganism could have unpredictable effects on Earth's ecosystems。 By using robotic handling systems on the Moon, researchers hope to eliminate the risk of accident
A groundbreaking superconducting X-ray spectrometer has begun operation at BESSY II, giving Europe its first TES-based system and boosting photon detection efficiency by up to 1,000 times。 The advance enables scientists to explore atomically thin materials, nanostructures, and ultra-dilute samples with remarkable speed and sensitivity
Ancient asteroid impacts may have done more than reshape Earth's surface—they could have helped spark life itself。 New computer models show the collisions created enormous underground hydrothermal systems by cracking the planet's crust and allowing hot water to flow through it。 These long-lasting, life-friendly environments may have covered much of
NASA is marking the United States' 250th birthday with four striking red, white, and blue images of deep space from the Chandra X-ray Observatory。 The collection features an exploded star, a stellar nursery, a galaxy where stars are rapidly forming, and a galaxy cluster that provides evidence for dark matter
The Earth may not be that massive, but it still distorts space-time
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—
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
Preclinical trial is testing the feasibility of humanoid robots in surgery
The AC culture wars may be solved by advances in environmentally friendly technology
The hunt for ancient life on Mars just got an important test run。 Scientists confirmed that the Rosalind Franklin rover's sophisticated instrument can detect subtle differences in two stable molecules that could preserve evidence of past life for billions of years。 But the team also uncovered a surprise: organic molecules in the Murchison meteorite