Friday, February 26th, 2016

Karl Voss – Gorkin, Pamela; Daepp, Ulrich, Voss, Karl; Shaffer, Andrew; and Sokolowsky, Benjamin. “Decomposing Finite Blaschke Products.” Journal of Mathematical Analysis and its Applications 426, no. 2 (2015) : 1201-1216.

Karl Voss, Associate Dean of Faculty

We present four algorithms to determine whether or not a Blaschke product is a composition of two non-trivial Blaschke products and, if it is, the algorithms suggest what the composition must be. The initial algorithm is a naive counting argument, the second considers critical values and the counting argument, the third is a geometric argument that exploits the relationship between Blaschke products and curves with the Poncelet property, and it can also be expressed in terms of a group associated with the Blaschke product. The final algorithm looks at inverse images under the Blaschke product. Our algorithms are accompanied by an applet that implements them.

Gorkin, Pamela; Daepp, Ulrich, Voss, Karl; Shaffer, Andrew; and Sokolowsky, Benjamin. “Decomposing Finite Blaschke Products.” Journal of Mathematical Analysis and its Applications 426, no. 2 (2015) : 1201-1216.

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Friday, February 26th, 2016

B. Ann Tlusty – Tlusty, B. Ann. “Invincible Blades and Invulnerable Bodies: Weapons Magic in Early-Modern Germany.” European Review of History-Revue Europeenne d’Histoire 22, no. 4 (2015) : 658-679.

B. Ann Tlusty, Associate Dean of Faculty

In the world of the occult, as in other realms, the tools and methods chosen by women and men reflected acceptable ways of “doing’ gender. This paper will concentrate on magical spells and blessings intended to give men an advantage in sword fights, make them invulnerable, or turn them into perfect marksmen. Because magical practices associated with guns and blades were related to early-modern thinking about masculine power and performance, they were less harshly treated than the kind of magic more often associated with women. Many of these hypermasculine spells drew on contemporary medical beliefs about natural sympathies, including the idea that sympathies existed between the dead and the living. For this reason, invulnerability and weapon spells usually included materials from male corpses (for example, body parts, moss growing on dead men’s skulls, and so on). As learned belief in natural magic waned during the Enlightenment, stories of magic blades and bullets retreated from courts and battlefields into the world of fiction and fantasy.

Tlusty, B. Ann. “Invincible Blades and Invulnerable Bodies: Weapons Magic in Early-Modern Germany.” European Review of History-Revue Europeenne d’Histoire 22, no. 4 (2015) : 658-679.

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Friday, February 26th, 2016

George Shields – Temelso, Berhane; Renner, Carla R.; and Shields, George C. “Importance and Reliability of Small Basis Set CCSD(T) Corrections to MP2 Binding and Relative Energies of Water Clusters.”Journal of Chemical Theory and Computation 11, no. 4 (2015) : 1439-1448.

George Shields, Dean of Arts & Sciences

MP2 describes hydrogen-bonded systems well, yet a higher-order electron correlation correction in the form of a CCSD(T) calculation is usually necessary to achieve benchmark quality energies. We evaluated the importance and reliability of small basis set CCSD(T) corrections to MP2 (delta(CCSD(T))(MP2)) both on the binding (Delta E) and relative (Delta Delta E) energies for a large number of systems including four water dimer stationary points and 57 other clusters up to undecamers, (H2O)11. By comparing the MP2 energies with CCSD(T) and the explicitly correlated MP2-F12 energies with variants of CCSD(T)-F12 using different basis sets, we were able to establish that the correction to the binding energy (Delta E) is sensitive to basis set size, especially for small double-zeta basis sets. On the other hand, the basis set sensitivity of the correction to the relative energy (Delta Delta E) within each cluster size is very small. While the delta(CCSD(T))(MP2) correction to the binding energy might vary in magnitude with basis set size, its effect on relative energy (and hence the stability of isomers) is remarkably consistent. Therefore, we recommend the inclusion of this correction to obtain the relative stability of closely spaced isomers using a double-zeta basis set with polarization and diffuse functions such as aug-cc-pVDZ.

Temelso, Berhane; Renner, Carla R.; and Shields, George C. “Importance and Reliability of Small Basis Set CCSD(T) Corrections to MP2 Binding and Relative Energies of Water Clusters.”Journal of Chemical Theory and Computation 11, no. 4 (2015) : 1439-1448.

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Friday, February 26th, 2016

George Shields – Swan, James; Findeis, Peter M.; Hilton, Sheena; Lebold, Kathryn M.; Temelso, Berhane; and Shields, George C. “Formation of Deprotonated 2-Imidazoline-4(5)-One Product Ions in the Collision-Induced Dissociation of Some Serine-Containing Dipeptides.” International Journal of Mass Spectrometry 381, (2015) : 25-32.

George Shields, Dean of Arts & Sciences

A deprotonated 2-imidazoline-4(5)-one product ion was observed as a major fragment in the collision-induced dissociation (CID) of several dipeptides containing serine at the C-terminal and an amino acid with an alkyl substituent at the N-terminal. This fragment becomes predominant at high collision energies. The same type of product ion was seen in the CID of cyclo(GlyGly). Labeling GlySer with O-18 suggests that the fragmentation may proceed through a symmetrical intermediate such as a deprotonated diketopiperazine. Density functional theory calculations of GlySer provided a possible mechanism for the fragmentation. (C) 2015 Elsevier B.V. All rights’ reserved.

Swan, James; Findeis, Peter M.; Hilton, Sheena; Lebold, Kathryn M.; Temelso, Berhane; and Shields, George C. “Formation of Deprotonated 2-Imidazoline-4(5)-One Product Ions in the Collision-Induced Dissociation of Some Serine-Containing Dipeptides.” International Journal of Mass Spectrometry 381, (2015) : 25-32.

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