#### Filter Results:

- Full text PDF available (30)

#### Publication Year

1974

2017

- This year (1)
- Last 5 years (18)
- Last 10 years (30)

#### Publication Type

#### Co-author

#### Journals and Conferences

#### Brain Region

#### Cell Type

#### Key Phrases

#### Method

#### Organism

Learn More

- A. S. Lewis
- 1995

A fundamental result of von Neumann's identifies unitarily invariant matrix norms as symmetric gauge functions of the singular values. Identifying the subdifferential of such a norm is important in matrix approximation algorithms, and in studying the geometry of the corresponding unit ball. We show how to reduce many convex-analytic questions of this kind… (More)

- C. Savio Chan, Kelly E. Glajch, +11 authors D. James Surmeier
- Nature neuroscience
- 2011

Parkinson's disease is a common neurodegenerative disorder characterized by a profound motor disability that is traceable to the emergence of synchronous, rhythmic spiking in neurons of the external segment of the globus pallidus (GPe). The origins of this pathophysiology are poorly defined for the generation of pacemaking. After the induction of a… (More)

- J M Borwein-And, A S Lewis
- 1991

This paper considers the minimization of a convex integral functional over the positive cone of an Lp space, subject to a finite number of linear equality constraints. Such problems arise in spectral estimation, where the objective function is often entropy-like, and in constrained approximation. The Lagrangian dual problem is finite-dimensional and… (More)

- A. S. Lewis
- Math. Oper. Res.
- 1996

A spectral function of a Hermitian matrix X is a function which depends only on the eigenvalues of X, 1 (X) 2 (X) : : : n (X), and hence may be written f(1 (X); 2 (X); : : :; n (X)) for some symmetric function f. Such functions appear in a wide variety of matrix optimization problems. We give a simple proof that this spectral function is diierentiable at X… (More)

- L Singh, A S Lewis, M J Field, J Hughes, G N Woodruff
- Proceedings of the National Academy of Sciences…
- 1991

The effect of neuropeptide cholecystokinin (CCK) receptor agonists and antagonists was examined in the rat elevated X-maze model of anxiety. The selective CCK-B receptor antagonists CI-988 (PD 134308) and L-365,260 produced anxiolytic-like effects, whereas MK-329, a CCK-A receptor antagonist, was respectively less potent by factors of 313 and 200. The… (More)

1. Gabapentin (neurontin) is a novel antiepileptic agent that binds to the alpha 2 delta subunit of voltage-dependent calcium channels. The only other compound known to possess affinity for this recognition site is the (S)-(+)-enantiomer of 3-isobutylgaba. However, the corresponding (R)-(-)-enantiomer is 10 fold weaker. The present study evaluates the… (More)

- L C Murphy, B Peng, +6 authors R Shiu
- Journal of molecular endocrinology
- 2005

To investigate the effect of altered oestrogen receptor (ER)alpha and ERbeta expression on oestrogen and anti-oestrogen action in breast cancer, we have stably expressed an inducible ERbeta1 in MCF7 breast cancer cells. Stably expressing clones were isolated and over-expression of ERbeta1 correlated with increased levels of specific radiolabelled oestradiol… (More)

- Alan S Lewis, Dane M Chetkovich
- Molecular and cellular neurosciences
- 2011

The roles of cells within the nervous system are based on their properties of excitability, which are in part governed by voltage-gated ion channels. HCN channels underlie the hyperpolarization-activated current, I(h), an important regulator of excitability and rhythmicity through control of basic membrane properties. I(h) is present in multiple neuronal… (More)

- Sukant Khurana, Zhiqiang Liu, Alan S Lewis, Kristen Rosa, Dane Chetkovich, Nace L Golding
- The Journal of neuroscience : the official…
- 2012

In sensory circuits of the brain, developmental changes in the expression and modulation of voltage-gated ion channels are a common occurrence, but such changes are often difficult to assign to clear functional roles. We have explored this issue in the binaural neurons of the medial superior olive (MSO), whose temporal precision in detecting the coincidence… (More)

- A S Lewis
- 1998

We prove the smallest possible norm of a linear perturbation making a closed convex process nonsurjective is the inverse of the norm of the inverse process. This generalizes the fundamental property of the condition number of a linear map. We then apply this result to strengthen a theorem of Renegar measuring the size of perturbation necessary to make an… (More)