Structural aging

In northern seas, fish such as herring, cod, haddock and flounder show intraspecies population differences in life span, structure, age at maturity and various physiological and biochemical characteristics (Shatunovsky, 1963, 1970 Love, 1970,1980 Storozhuk, 1971 Lapin, 1973). In contrast, fish from the Black, Azov and Mediterranean Seas have shorter life spans and display less distinct intraspecifc differences. Moreover, within one sea population, fish of one species do not differ much in age structure, fecundity or spawning character. The most pronounced difference in the latter group of species is the rate of lipid accumulation in sprat from different sites in the Black Sea and anchovy in the Azov Sea (Shulman, 1972b). Comparison of anchovy from the Azov, Black and Mediterranean Seas shows more marked differences in the levels of accumulated lipid and the growth rate (Chapter 2). 

The number nx at time t + 1 of all other age classes is calculated by multiplying the number of individuals in the preceding age class, nt v by the survival rate of those individuals into the next age class,, S for example 2,+i = in The other age classes of the population vector cannot contribute to n2. Thus, the transition or Leslie matrix in Equation 3.1 has a typical structure age-dependent fecundities in the first row and age-dependent survival rates in the subdiagonal (Caswell 2001 Chapter 5). 

A) Torpedo AChR-DFP iiged adduct. DFP is covalently attached 10 the active Ser200. The gray ribbon and selected side chain sticks represent unliganded Torpedo AChE structure, Aged DFP AChE adduct i.s shown as black ribbon and sticks,... 

For any given cooling schedule, when an amorphous polymer undergoes a glass transition while the free volume no longer percolates through the structure, the available fraction is still systematically reduced by structural aging if the polymer... 

Various terms are u in the literature for the development of a network structure ageing, annealing and maturation. In many cases network formation is clearly time dependent. In other cases network formation seems to be instantaneous and a time dependence cannot be observed. In physical networks this may be the result of a sudden temperature decrease, resulting in a spinodal phase separation. During network formation the increase in the storage modulus may be of the order of 10 or more. It is clear that a horizontal plateau... 

Schaie, K Warner, and Laura L. Carstensen, eds. Social Structures, Aging, and Self-Regulation in the Elderly. New York Springer, 2006. Examines the evolution of personal and social roles in aging with particular emphasis on familial changes, immigration, and increased life span. 

The broad applicability of structural composites in society, along with the equally broad apphcations that already exist, make it very difficult to predict any specific future developments in the field. It is certain that an ongoing need exists for the maintenance and repair of the present composites infrastructure. Concrete structures age and require maintenance or replacement. Similarly, FRP materials break down over time through environmental action, eventually... 

Sarjeant WJ, MacDougall FW, Larson DW (1997) Energy storage in polymer laminate structures-ageing and diagnostic approaches for life validation. IEEE Electr fiisul Mag 13 20... 

Bones must be thought of as more like plastic than like stone. They have a good deal of flexibility and can accommodate and distribute stresses within a certain capacity of tolerance. The amount, interval, and impulse of the force, as well as the vector, direction, and individual structure, age, and nutritional status of the bone help to determine the result. Sudden forces may create bending, as in a green-stick fracture in children, or rapture of the components and related structures. Sometimes the force is transmitted to smrounding or imderlying structures of other types. It is difficult to conceive of any instance when a fracture of bone does not involve also soft tissue injmy of the regional structures. 

A.S23. Information shall be provided which shows that all materials which have been selected for the construction of safety relevant components and structures can withstand the nuclear and chemical environment to which they are subjected, without unacceptable worsening of the performance of the safety functions of such components and structures. Ageing effects due to the deterioration of properties, as well as irradiation damage shall be included. 

Ronsin O, CaroQ C, Baumbeiger T (2009) Interplay between shear loading tmd structural aging in a physical gelatin gel. Phys Rev Lett 103(13) 138302... 

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