Background: The spinal column possesses shock absorption properties, mainly provided by the intervertebral discs. However, with the process of senescence, all structures of the spine, including the discs, undergo degenerative changes. It may lead to alteration of the mechanical properties of the spinal motion segment and diminished capacity for vibration attenuation.
Objective: The objective of this study was to investigate the age-related changes in shock absorption properties of the spine.
Patients And Methods: A total of 112 individuals divided into three groups according to age (third, fifth, and seventh decades of life) were enrolled in this study. The transmissibility of vibrations through the spine was measured in a standing position on a vibration platform by accelerometers mounted at the levels of S2 and C0. Registered signals were described using four parameters: VMS (variability), peak-to-peak amplitude (PPA), and spectral activity in two bands F2 (0.7-5 Hz) and F20 (15-25 Hz).
Results: In all age groups, signals registered at C0 were characterized by significantly lower values of VMS, PPA, and F20, when compared to level S2. Simultaneously, the parameter F20 significantly differed among all age groups when C0 vibrations were analyzed: 2.43±1.93, 5.02±3.61, and 10.84±5.12 for the third, fifth, and seventh decades of life, respectively.
Conclusion: The human spinal column provides vibration attenuation; however, this property gradually declines with the aging process.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5963482 | PMC |
http://dx.doi.org/10.2147/CIA.S156298 | DOI Listing |
Materials (Basel)
January 2025
School of Electrical & Control Engineering, Tongmyong University, Busan 48520, Republic of Korea.
Resilient mounts play a vital role in anti-vibration and shock-absorption systems, making precise estimation of their static and dynamic stiffness essential for ensuring optimal mechanical performance and effective design. This study investigates the behavior of resilient mounts by analyzing their static and dynamic stiffness characteristics through the application of various hyperelastic constitutive models. Seven hyperelastic models were reviewed and systematically compared using numerical simulations, experimental data, and analytical solutions.
View Article and Find Full Text PDFMicromachines (Basel)
December 2024
The 41 Institute of the Sixth Academy of China Aerospace Science and Industry, Hohhot 010010, China.
Ammonium dinitramide (ADN) is a new green oxidant, which is a kind of high-energy ionic liquid and has been widely used in the field of liquid propulsion. When it is used in laser plasma propulsion, its poor absorption coefficient significantly limits its application. To address the issue, this paper investigates the effects of the content of the infrared dye and the laser energy density on the laser propulsion performance of an ADN-based liquid propellant.
View Article and Find Full Text PDFJ Ethnopharmacol
January 2025
Department of Biopharmacy, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland; Department of Biochemistry and Toxicology, University of Life Sciences, Akademicka 13, 20-950, Lublin, Poland. Electronic address:
Background: The human gut microbiota plays a crucial role in various aspects of health, extending beyond digestion and nutrient absorption. Ganoderma lucidum (Reishi) and Hericium erinaceus (Lion's Mane), traditional medicinal mushrooms, have garnered interest due to their potential to exert positive health effects. The aim of our study was to investigate the molecular impact of Reishi and Lion's Mane on mood regulation through the gut-brain axis.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Intermolecular hydrogen bonds between carboxyl (COO) and amino groups are a common weak interaction in proteins. Infrared (IR) spectral assignment of such an intermolecular hydrogen bond provides a fingerprint for studying protein-protein interactions as its absorption frequency is affected by the molecular electrostatic environment. Temperature-dependent FTIR and temperature-jump time-resolved IR absorbance difference spectra of several typical amino acids and those of wild type and single-site mutated αB-crystallin were performed.
View Article and Find Full Text PDFDalton Trans
January 2025
Shock Wave Research Laboratory, Department of Physics, Abdul Kalam Research Centre, Sacred Heart College, Tirupattur, affiliated to Thiruvalluvar University, Serkkadu, Tamil Nadu, 635 601, India.
In this study, Zinc Telluride (ZnTe) was subjected to acoustic shock waves with a Mach number of 1.5, transient pressure of 0.59 MPa, and a temperature of 520 K to analyze its stability against shock wave impact.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!