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Aging changes in the very elderly cardiac disease are associated with physiological and pathological changes, however, all observed changes in aging are associated with a deterioration of cardiorespiratory fitness function. For example, hypertension and cardiorespiratory disease make difficult distinctions between normal aging changes and the effects of underlying resveratrol supplements processes. Cardiorespiratory fitness-independent changes in resveratrol intake are still unclear. This review aimed to discuss whether the aging-associated cardiorespiratory fitness changes in the heart can be reversed by resveratrol supplements, and the mechanisms of cardiorespiratory fitness. Aging led to apoptosis and fibrosis-related protein expression increased, however, cardiorespiratory fitness had revered more functions. Resveratrol supplements in combination with cardiorespiratory fitness had a good enhanced mitochondrial function in aging including IL-6, STAT3, MEK5, and MEK1/ERK1 increased. Resveratrol supplements also induced survival signals and downregulation of apoptosis signaling in aging. Therefore, we suggest resveratrol has enhanced cardiorespiratory fitness to combine their function in repressed aging.

To improve the poor transverse shear resistance of corrugated sandwich cores, the present study uses a combined analytical and numerical approach to exploit the idea of filling core interstices with polymer foam. For foam-filled corrugated cores under transverse shear, four collapse modes are considered: elastic buckling, plastic buckling or yielding/fracture of corrugated strut, interfacial debonding/sealing off between corrugation platform and face sheets, and foam shear failure. Analytical models are constructed to determine the transverse shear stiffness and strength. To estimate the elastic/plastic buckling strength of a corrugated strut, the foam insertions are treated as a superposition of Winkler type elastic foundations to support the strut against buckling. Finite element simulations are carried out to validate the model predictions, with good agreement achieved. The sensitivity of transverse shear strength and failure mode to corrugation angle, strut slenderness and strain hardening of strut parent material is systematically studied; collapse mechanism map is constructed, and minimum weight design is carried out. Whether the sandwich is made of metal or fiber-reinforced composite, it is demonstrated that the foam-filled corrugated core exhibits radically enhanced transverse shear response, outperforming competing core topologies such as hollow pyramidal lattices and square honeycombs on the basis of equal mass.