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Leaf decay in seagrasses is enhanced in some seasons since large green senescent beach-cast seagrass leaves are frequently recorded during autumn and winter seasons. Here, we explore if senescence is operating in seagrass leaf decay or if hydrodynamic stress is responsible for the seasonal leaf abscission. A seasonal study on the temperate seagrass Cymodocea nodosa was carried out in four locations with contrasting hydrodynamic regimes. The morphological, biomechanical and material properties of C. nodosa were measured. The force required to break the ligule was always lower than that required to break the blade. This could be considered an adaptive strategy to reduce acute drag forces and thus lessen the chance of plant uprooting. The absolute force needed to dislodge the blade at the ligule level varied with season and location, with the lowest forces recorded in autumn. This may indicate that senescence is operating in this species. On the other hand, the minimum estimated failure velocities for leaf abscission were also recorded in autumn. Consequently, this may cause the premature shedding of leaves in this season before the senescence process has finished and can probably explain the occurrence of green beach-cast seagrass leaves usually found during autumn and winter. [ABSTRACT FROM AUTHOR]

The breaking strength (σ) and stress-strain relation of several muscles [biceps femoris (BF), semitendinosus (ST) and semimembranosus (SM)] and the subcutaneous fat (SF) from a Spanish dry cured ham (Protected Designation of Origin of white ham from "Teruel") have been analysed by the uniaxial tensile test in order to predict the mechanical behaviour of this meat product. Thirty pieces were analysed and the stress-strain curves were obtained. A great dispersion of the σ values was observed. This leads to the necessity of employing statistical analyses to illustrate the extent to which strength values may vary. The Weibull analysis was applied to estimate the fracture probability. SM and SF showed the highest characteristic strength. The low values of the Weibull modulus indicate that dry-cured ham tissues behave as brittle materials. The stress-strain curves present characteristic forms for BF, ST and SM, which may be associated with their composition and the extent to which they are affected by the curing process., (Copyright © 2014 Elsevier Ltd. All rights reserved.)