By invoking Bogoliubov's spectrum, we show that for the nonlinear Schrödinger equation, the modulation instability (MI) of its n=1 Fourier mode on a finite background automatically triggers a further cascading instability, forcing all the higher modes to grow exponentially in locked step with the n=1 mode. This fundamental insight, the enslavement of all higher modes to the n=1 mode, explains the formation of a triangular-shaped spectrum that generates the Akhmediev breather, predicts its formation time analytically from the initial modulation amplitude, and shows that the Fermi-Pasta-Ulam (FPU) recurrence is just a matter of energy conservation with a period twice the breather's formation time. For higher-order MI with more than one initial unstable mode, while most evolutions are expected to be chaotic, we show that it is possible to have isolated cases of "super-recurrence," where the FPU period is much longer than that of a single unstable mode.
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http://dx.doi.org/10.1103/PhysRevE.92.063202 | DOI Listing |
J Mammary Gland Biol Neoplasia
January 2025
Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
Fluorescent biosensors offer a powerful tool for tracking and quantifying protein activity in living systems with high temporospatial resolution. However, the expression of genetically encoded fluorescent proteins can interfere with endogenous signaling pathways, potentially leading to developmental and physiological abnormalities. The EKAREV-NLS mouse model, which carries a FRET-based biosensor for monitoring extracellular signal-regulated kinase (ERK) activity, has been widely utilized both in vivo and in vitro across various cell types and organs.
View Article and Find Full Text PDFSleep Breath
January 2025
Department of Pulmonary and Critical Care Medicine, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, No.1 Da Hua Road, Dong Dan, Dongcheng District, Beijing, 100730, PR China.
Purpose: To investigate the relationship between obstructive sleep apnea hypopnea syndrome (OSAHS) severity and fat, bone, and muscle indices.
Methods: This study included 102 patients with OSAHS and retrospectively reviewed their physical examination data. All patients underwent polysomnography, body composition analysis, dual-energy X-ray absorptiometry, computed tomography (CT) and blood test.
Arch Dermatol Res
January 2025
Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
We have recently shown that fluoxetine (FX) suppressed polyinosinic-polycytidylic acid-induced inflammatory response and endothelin release in human epidermal keratinocytes, via the indirect inhibition of the phosphoinositide 3-kinase (PI3K)-pathway. Because PI3K-signaling is a positive regulator of the proliferation, in the current, highly focused follow-up study, we assessed the effects of FX (14 µM) on the proliferation and differentiation of human epidermal keratinocytes. We found that FX exerted anti-proliferative actions in 2D cultures (HaCaT and primary human epidermal keratinocytes [NHEKs]; 48- and 72-h; CyQUANT-assay) as well as in 3D reconstructed epidermal equivalents (48-h; Ki-67 immunohistochemistry).
View Article and Find Full Text PDFCell Mol Life Sci
January 2025
Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, Unitat de Farmacologia, Universitat de Barcelona, Av. Joan XXIII 27-31, 08028, Barcelona, Spain.
Nuclear growth differentiation factor 15 (GDF15) reduces the binding of the mothers' against decapentaplegic homolog (SMAD) complex to its DNA-binding elements. However, the stimuli that control this process are unknown. Here, we examined whether saturated fatty acids (FA), particularly palmitate, regulate nuclear GDF15 levels and the activation of the SMAD3 pathway in human skeletal myotubes and mouse skeletal muscle, where most insulin-stimulated glucose use occurs in the whole organism.
View Article and Find Full Text PDFInorg Chem
January 2025
College of Chemistry and Materials Science, College of Environmental and Resource Sciences, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Normal University, Fuzhou 350007, China.
The glassy state of inorganic-organic hybrid metal halides combines their excellent optoelectronic properties with the outstanding processability of glass, showcasing unique application potential in solar devices, display technologies, and plastic electronics. Herein, by tailoring the organic cation from -phenylpiperazine to dimethylamine gradually, four types of zero-dimensional antimony halides are obtained with various optical and thermal properties. The guest water molecules in crystal (-phenylpiperazine)SbCl·Cl·5HO lead to the largest distortion of the Sb-halogen unit, resulting in the red emission different from the yellow emission of other compounds.
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