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We reconsider the matrix model formulation of type IIB superstring theory in (9+1)-dimensional space-time. Unlike the previous works in which the Wick rotation was used to make the model well defined, we regularize the Lorentzian model by introducing infrared cutoffs in both the spatial and temporal directions. Monte Carlo studies reveal that the two cutoffs can be removed in the large-N limit and that the theory thus obtained has no parameters other than one scale parameter. Moreover, we find that three out of nine spatial directions start to expand at some "critical time," after which the space has SO(3) symmetry instead of SO(9).
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http://dx.doi.org/10.1103/PhysRevLett.108.011601 | DOI Listing |
PLoS One
September 2025
School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an, China.
Accurate prediction of time-varying dynamic parameters during the milling process is a prerequisite for chatter-free cutting of thin-walled parts. In this paper, a matrix iterative prediction method based on weighted parameters is proposed for the time-varying structural modes during the milling of thin-walled blade structures. The thin-walled blade finite element model is established based on the 4-node plate element, and the time-varying dynamic parameters of the workpiece during the cutting process can be obtained by modifying the thickness of the nodes through the constructed mesh element finite element model It is not necessary to re-divide the mesh elements of the thin-walled parts at each cutting position, thus improving the calculation efficiency of the dynamic parameters of the workpiece.
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
September 2025
Stochastic Kriging (SK) is a generalized variant of Gaussian process regression, and it is developed for dealing with non-i.i.d.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2025
Department of Bioengineering, Stanford University, Stanford, CA 94305.
Despite periods of permanent darkness and extensive ice coverage in polar environments, photosynthetic ice diatoms display a remarkable capability of living inside the ice matrix. How these organisms navigate such hostile conditions with limited light and extreme cold remains unknown. Using a custom subzero temperature microscope during an Arctic expedition, we present the finding of motility at record-low temperatures in a Eukaryotic cell.
View Article and Find Full Text PDFVet Res Commun
September 2025
Department of Animal Industry Convergence, Kangwon National University, Chuncheon, 24341, Republic of Korea.
Global warming causes heat stress in livestock, impairing their health, welfare, and productivity. In bovines, chronic stress elevates cortisol levels; however, this response often goes undetected due to the lack of practical biomatrices for accurate assessment. Common biomatrices such as blood require repeated sampling that may affect measurement accuracy.
View Article and Find Full Text PDFHum Vaccin Immunother
December 2025
Department of Epidemiology, Ministry of Education Key Laboratory of Public Health Safety, School of Public Health, Fudan University, Shanghai, China.
Human papillomavirus (HPV) causes multiple diseases in both sexes. This study evaluates the cost-effectiveness and epidemiological impact - defined as reductions in HPV-related disease cases - of a gender-neutral vaccination (GNV) strategy in China's economically developed metropolises: Beijing, Shanghai, and Guangzhou. A discrete-time Markov model simulated no vaccination, female-only vaccination (FOV), and GNV strategies among 12-year-olds.
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