A seemingly ubiquitous irrational number often appearing in nature and in man-made things like structures, paintings, and physical systems, is the golden number. Here, we show that this astonishing number appears in the periodic solutions of an underactuated mass-spring oscillator driven by a nonlinear self-excitation. Specifically, by using the two-time scale perturbation method, it is analytically demonstrated that the golden number appears in the ratio of amplitudes, as well as in the oscillation frequency of the periodic solution, which is referred to as golden solution and, by applying the Poincaré method, it is demonstrated that this solution is asymptotically stable. Additionally, the analytic results are illustrated by means of numerical simulations and also, an experimental study is conducted.
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http://dx.doi.org/10.1038/s41598-022-13485-7 | DOI Listing |
Child Care Health Dev
January 2025
Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, UK.
Background And Objectives: Some families faced difficulties accessing speech therapy in some areas of Malaysia and/or during the COVID-19 lockdown. Therefore, parent-mediated intervention could be one of the ways to solve this issue, as it has been proven to effectively improve communication skills among children with communication disorders. Hence, a Mandarin parental guidebook comprising a series of language stimulation activities was developed to explore the perception of parents of children with communication disorders, ranging from 3 to 6 years old, regarding the feasibility of (1) conducting speech-language home programs and (2) using a home-based parental guidebook as a tool to deliver a speech-language home program.
View Article and Find Full Text PDFBMC Bioinformatics
January 2025
Department of Chemistry, University of Louisiana at Lafayette, Lafayette, LA, 70504, USA.
Background: All chemical forms of energy and oxygen on Earth are generated via photosynthesis where light energy is converted into redox energy by two photosystems (PS I and PS II). There is an increasing number of PS I 3D structures deposited in the Protein Data Bank (PDB). The Triangular Spatial Relationship (TSR)-based algorithm converts 3D structures into integers (TSR keys).
View Article and Find Full Text PDFBMJ Open
December 2024
British Heart Foundation Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK
Introduction: Ischaemic heart disease (IHD) and cerebrovascular disease are leading causes of morbidity and mortality worldwide. Cerebral small vessel disease (CSVD) is a leading cause of dementia and stroke. While coronary small vessel disease (coronary microvascular dysfunction) causes microvascular angina and is associated with increased morbidity and mortality.
View Article and Find Full Text PDFACS Synth Biol
January 2025
Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, U.K.
Cloning methods are fundamental to synthetic biology research. The capability to generate custom DNA constructs exhibiting predictable protein expression levels is crucial to the engineering of biology. Golden Gate cloning, a modular cloning (MoClo) technique, enables rapid and reliable one-pot assembly of genetic parts.
View Article and Find Full Text PDFJ Ethnopharmacol
January 2025
Eye School of Chengdu University of Traditional Chinese Medicine. Ineye Hospital of Chengdu University of Traditional Chinese Medicine, KeyLaboratory of Sichuan Province Ophthalmopathy Prevention & Cureand Visual Function Protection with Traditional Chinese Medicine Laboratory. Electronic address:
Ethnopharmacological Relevance: Dahuang-Gancao decoction (DGD) is a traditional Chinese medicinal formula that is recorded in the Synopsis of the Golden Chamber, and is widely used to treat damp-heat in the body. Since the pathological factors of androgenetic alopecia (AGA) also reflect damp-heat blockage, DGD has great potential for the treatment of AGA and has been used effectively in clinical practice.
Aim Of The Study: The aim of the study was to investigate whether external application of DGD could promote the activation and proliferation of hair follicle stem cells (HFSCs) and improve AGA through the Wnt/β-catenin pathway.
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