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Longer-lasting materials and products are often promoted as a strategy to increase resourcefulness and sustainability across product groups including fashion. Yet these gains depend on changed user behavior and consumption patterns, which in fashion in particular are influenced by social and experiential dimensions, not just material products. Obsolescence of fashion products, driven by aesthetic change and tied to changing social preferences underscores the psycho-social nature of factors which affect fashion garment lifespans. This is reflected by ethnographic evidence that shows that garments which defy obsolescence do so in informal or unintentional ways, rarely as a result of design planning or material or product qualities. This article suggests a point of departure for design for durability that shifts away from a familiar focus on materials, products, and user-object relationships to instead explore material durability as emerging from strategies of human action. It suggests that durability, while facilitated by materials, design, and construction, is determined by an ideology of use

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Progression through meiosis requires two waves of maturation promoting factor (MPF) activity corresponding to meiosis I and meiosis II. Frog oocytes contain a pool of inactive ‘pre-MPF’ consisting of cyclin-dependent kinase 1 bound to B-type cyclins, of which we now find three previously unsuspected members, cyclins B3, B4 and B5. Protein synthesis is required to activate pre-MPF, and we show here that this does not require new B-type cyclin synthesis, probably because of a large maternal stockpile of cyclins B2 and B5. This stockpile is degraded after meiosis I and consequently, the activation of MPF for meiosis II requires new cyclin synthesis, principally of cyclins B1 and B4, whose translation is strongly activated after meiosis I. If this wave of new cyclin synthesis is ablated by antisense oligonucleotides, the oocytes degenerate and fail to form a second meiotic spindle. The effects on meiotic progression are even more severe when all new protein synthesis is blocked by cycloheximide added after meiosis I, but can be rescued by injection of indestructible B-type cyclins. B-type cyclins and MPF activity are required to maintain c-mos and MAP kinase activity during meiosis II, and to establish the metaphase arrest at the end of meiotic maturation. We discuss the interdependence of c-mos and MPF, and reveal an important role for translational control of cyclin synthesis between the two meiotic divisions.