34 research outputs found
Global and exponential attractors for a Ginzburg-Landau model of superfluidity
The long-time behavior of the solutions for a non-isothermal model in
superfluidity is investigated. The model describes the transition between the
normal and the superfluid phase in liquid 4He by means of a non-linear
differential system, where the concentration of the superfluid phase satisfies
a non-isothermal Ginzburg-Landau equation. This system, which turns out to be
consistent with thermodynamical principles and whose well-posedness has been
recently proved, has been shown to admit a Lyapunov functional. This allows to
prove existence of the global attractor which consists of the unstable manifold
of the stationary solutions. Finally, by exploiting recent techniques of
semigroups theory, we prove the existence of an exponential attractor of finite
fractal dimension which contains the global attractor.Comment: 39 page
Marking their own homework: The pragmatic and moral legitimacy of industry self-regulation
When is industry self-regulation (ISR) a legitimate form of governance? In principle, ISR can serve the interests of participating companies, regulators and other stakeholders. However, in practice, empirical evidence shows that ISR schemes often under-perform, leading to criticism that such schemes are tantamount to firms marking their own homework. In response, this paper explains how current management theory on ISR has failed to separate the pragmatic legitimacy of ISR based on self-interested calculations, from moral legitimacy based on normative approval. The paper traces three families of management theory on ISR and uses these to map the pragmatic and moral legitimacy of ISR schemes. It identifies tensions between the pragmatic and moral legitimacy of ISR schemes, which the current ISR literature does not address, and draws implications for the future theory and practice of ISR
The 'mechanism' of human cognitive variation
The theory of psychosis and autism as diametrical disorders offers a tractable and testable view of normal and abnormal human cognitive variation as a function of opposing traits grouped by their selection for maternal and paternal reproductive fitness. The theory could be usefully rooted and developed with reference to the lower-level perceptual and attentional phenomena from which social cognitive modules are developmentally refined
Apple tree adaptation to shade in agroforestry: an architectural approach
International audiencePREMISE: The expression of shade adaptation traits is expected to be stronger in low light and can be detrimental to flowering and yield. Our study focused on the expression of shade adaptation traits of apple trees (Malus domestica Borkh. ‘Dalinette’) in an agroforestry system.METHODS: The architecture of 45 apple trees in their third and fourth year was extensively described and analyzed at the tree scale and compared depending on the light quantity received during the growing season. Flower cluster phenology and the relation between leaf area and floral initiation were also investigated.RESULTS: The number of growing shoots and the leaf area were reduced by shade even if specific leaf area increased with increasing shade. Shade did not modify primary growth but did decrease secondary growth, so that apple tree shoots in shade were slender, with a lower taper and reduced number and proportion of flower clusters. The correlation between floral initiation and leaf area was high both in full and moderate light but not for apple trees in low light. Shade did not impact the date of bud burst and the early phenological stages of flower clusters, but it reduced the number of days at full bloom.CONCLUSIONS: Our results suggest that while the architecture of apple trees is modified by a reduction in light intensity, it is not until a reduction of 65% that the capability to produce fruit is impeded. These results could help optimize the design of apple-tree-based agroforestry systems