The ice surface is known for presenting a very small kinetic friction coefficient, but the origin of this property remains highly controversial to date. In this work, we revisit recent computer simulations of ice sliding on atomically smooth substrates, using newly calculated bulk viscosities for the TIP4P/ice water model. The results show that spontaneously formed premelting films in static conditions exhibit an effective viscosity that is about twice the bulk viscosity. However, upon approaching sliding speeds in the order of m/s, the shear rate becomes very large, and the viscosities decrease by several orders of magnitude. This shows that premelting films can act as an efficient lubrication layer despite their small thickness and illustrates an interesting interplay between confinement enhanced viscosities and shear thinning. Our results suggest that the strongly thinned viscosities that operate under the high speed skating regime could largely reduce the amount of frictional heating.
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Sci Rep
January 2025
Commercial Product R&D Institute, Dongfeng Automobile Co., Ltd., Wuhan, 430070, People's Republic of China.
The rapid acceleration of urbanization and the surge in car ownership necessitate efficient automatic parking solutions in constricted spaces to address the escalating urban parking issue. To optimize space utilization, enhance traffic efficiency, and mitigate accident risks, a method is proposed for smooth, comfortable, and adaptable automatic parking trajectory planning. This study initially employs a hybrid A* algorithm to generate a preliminary path, then fits the velocity and acceleration based on a cubic polynomial.
View Article and Find Full Text PDFNat Chem Biol
January 2025
State Key Laboratory of Chemo/Biosensing and Chemometrics and School of Chemistry and Chemical Engineering, Hunan University, Changsha, China.
Artificial metalloenzymes (ArMs) integrated within whole cells have emerged as promising catalysts; however, their sensitivity to metal centers remains a systematic challenge, resulting in diminished activity and turnover. Here we address this issue by inducing in cellulo liquid-liquid phase separation through a self-labeling fusion protein, HaloTag-SNAPTag. This strategy creates membraneless, isolated liquid condensates within Escherichia coli as protective compartments for the assembly of ArMs using the same fusion protein.
View Article and Find Full Text PDFSci Rep
January 2025
School of Safety and Management Engineering, Hunan Institute of Technology, Hengyang, 421002, China.
The extraction of coal seams with high gas content and low permeability presents significant challenges, particularly due to the extended period required for gas extraction to meet safety standards and the inherently low extraction efficiency. Hydraulic fracturing technology, widely employed in the permeability enhancement of soft and low-permeability coal seams, serves as a key intervention. This study focuses on the high-rank raw coal from the No.
View Article and Find Full Text PDFRinsho Ketsueki
January 2025
Department of Hematology, Kochi Medical School Hospital, Kochi University.
Primary hepatic lymphoma (PHL) is a lymphoproliferative disorder confined to the liver, with no evidence of lymphomatous involvement in other organs. Here, we report a case of diffuse large B-cell lymphoma (DLBCL)-type PHL in a patient with a long history of primary biliary cholangitis (PBC) and Sjögren's syndrome (SS). A 78-year-old woman presented with epigastralgia and was found to have a solitary liver tumor by contrast-enhanced computed tomography (CT).
View Article and Find Full Text PDFNaunyn Schmiedebergs Arch Pharmacol
January 2025
School of Human Sciences, London Metropolitan University, London, UK.
Mpox, formerly known as monkeypox, is a zoonotic disease caused by the Mpox virus (MPXV), which has recently attracted global attention due to its potential for widespread outbreaks. Initially identified in 1958, MPXV primarily spreads to humans through contact with infected wild animals, particularly rodents. Historically confined to Africa, the virus has expanded beyond endemic regions, with notable outbreaks in Europe and North America in 2022, especially among men who have sex with men (MSM).
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