Brendan Keith

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In the context of finite elements, construction of higher order shape functions for elements forming the exact sequence has been a long standing activity in both engineering and numerical analysis communities. A comprehensive review of the subject can be found for example in Demkowicz (2006), Demkowicz et al. (2007) and references therein. This document(More)
The flexibility of the DPG methodology is exposed by solving the linear elasticity equations under different variational formulations, including some with non-symmetric functional settings (different infinite-dimensional trial and test spaces). The family of formulations presented are proved to be mutually ill or well-posed when using traditional energy(More)
This article presents a general approach akin to domain-decomposition methods to solve a single linear PDE, but where each subdomain of a partitioned domain is associated to a distinct variational formulation coming from a mutually well-posed family of broken variational formulations of the original PDE. It can be exploited to solve challenging problems in(More)
A finite element methodology for large classes of variational boundary value problems is defined which involves discretizing two linear operators: (1) the differential operator defining the spatial boundary value problem; and (2) a Riesz map on the test space. The resulting linear system is overdetermined. Two different approaches for solving the system are(More)
Cucumber hypocotyls were extracted and the extract centrifuged at 100,000g to yield a supernatant or cytosol fraction. Binding of [(3)H]-gibberellin(4) (GA(4)) to soluble macromolecular components present in the cytosol was demonstrated at 0 C by Sephadex chromatography. Binding assays performed with cytosol that had been preheated or incubated with(More)
Barley (c.v. Himalaya) aleurone layers were incubated in [(3)H]gibberellin A(1) (GA(1)) at low temperatures. At 3 and 4 C, (3)H-activity was steadily accumulated in aleurone layers, and this accumulation was correlated with significant [(3)H]GA(1) metabolism. At 1 and 1.5 C, metabolism could not be detected, and at these temperatures aleurone layers(More)
1. I N T R O D U C T I O N With a natural capacity to accommodate problems with non-symmetric functional settings, the discontinuous Petrov–Galerkin (DPG) methodology [24, 27] has proven its merit in many areas of engineering interest [36, 37, 39, 40, 48, 60, 65, 66]. Desirable features of DPG methods include intrinsic numerical stability [17, 25, 30], a(More)
Binding of [(3)H]gibberellin A(1) (GA(1)) to extracts of dwarf pea epicotyls was investigated using sliced pea epicotyls (0.5-1.0 millimeter thick) that had been incubated in a solution containing [(3)H]GA(1) at 0 C for 3 days. Gel filtration of a 100,000g supernatant indicated binding to a high (HMW) and an intermediate molecular weight (IMW) fraction with(More)
A rapid method for assaying [(3)H]gibberellin A(4) bound to a soluble protein from cucumber hypocotyls by using DEAE-cellulose filter discs is described. The binding is saturable, reversible with unlabeled gibberellin A(4), and has a half-life of association under nonequilibrium conditions at 0-4 degrees C of 6-7 min. By using this assay, the dissociation(More)
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