A single-wave-number representation of a nonlinear energy spectrum, i.e., a stretching-energy spectrum, is found in elastic-wave turbulence governed by the Föppl-von Kármán (FvK) equation. The representation enables energy decomposition analysis in the wave-number space and analytical expressions of detailed energy budgets in the nonlinear interactions. We numerically solved the FvK equation and observed the following facts. Kinetic energy and bending energy are comparable with each other at large wave numbers as the weak turbulence theory suggests. On the other hand, stretching energy is larger than the bending energy at small wave numbers, i.e., the nonlinearity is relatively strong. The strong correlation between a mode a(k) and its companion mode a(-k) is observed at the small wave numbers. The energy is input into the wave field through stretching-energy transfer at the small wave numbers, and dissipated through the quartic part of kinetic-energy transfer at the large wave numbers. Total-energy flux consistent with energy conservation is calculated directly by using the analytical expression of the total-energy transfer, and the forward energy cascade is observed clearly.
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http://dx.doi.org/10.1103/PhysRevE.90.063004 | DOI Listing |
J Infect Dev Ctries
December 2024
Chest Dpt., Ahmed Maher Teaching Hospital, GOTHI, Cairo, Egypt.
Introduction: The present study aimed to explore the epidemiologic threats and factors associated with the coronavirus disease 2019 (COVID-19)-associated mucormycosis (CAM) epidemic that emerged in Egypt during the second COVID-19 wave. The study also aimed to explore the diagnostic features and the role of surgical interventions of CAM on the outcome of the disease in a central referral hospital.
Methodology: The study included 64 CAM patients from a referral hospital for CAM and a similar number of matched controls from COVID-19 patients who did not develop CAM.
Lancet Neurol
February 2025
Department of Clinical Neurological Sciences, University of Western Ontario, London, ON, Canada; Department of Cognitive Neurology, St Joseph's Health Care London, London, ON, Canada. Electronic address:
Background: No treatments exist for apathy in people with frontotemporal dementia. Previously, in a randomised double-blind, placebo-controlled, dose-finding study, intranasal oxytocin administration in people with frontotemporal dementia improved apathy ratings on the Neuropsychiatric Inventory over 1 week and, in a randomised, double-blind, placebo-controlled, crossover study, a single dose of 72 IU oxytocin increased blood-oxygen-level-dependent signal in limbic brain regions. We aimed to determine whether longer treatment with oxytocin improves apathy in people with frontotemporal dementia.
View Article and Find Full Text PDFJ Gerontol B Psychol Sci Soc Sci
January 2025
Department of Geriatric Medicine, Radboud university medical center, Nijmegen, The Netherlands.
Objective: Maintaining a strong social network in later life can be challenging due to limited resources, life events, and changes in health. Social internet use provides an accessible way for communication that is less susceptible to age-related challenges. Although social internet use is increasingly used by older adults, we do not know how social internet use shapes older adults' offline networks.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Mechanical Engineering, University of Siegen, Paul-Bonatz-Straße 9-11, 57076 Siegen, Germany.
This work leverages ultrasonic guided waves (UGWs) to detect and localize damage in structures using lightweight Artificial Intelligence (AI) models. It investigates the use of machine learning (ML) to train the effects of the damage on UGWs to the model. To reduce the number of trainable parameters, a physical signal processing approach is applied to the raw data before passing the data to the model.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Psychological and Cognitive Sciences, Tsinghua University, Beijing 100084, China.
The objective identification of depression using physiological data has emerged as a significant research focus within the field of psychiatry. The advancement of wearable physiological measurement devices has opened new avenues for the identification of individuals with depression in everyday-life contexts. Compared to other objective measurement methods, wearables offer the potential for continuous, unobtrusive monitoring, which can capture subtle physiological changes indicative of depressive states.
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