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A variational method for the calculation of spin-rovibronic energy levels of any triatomic molecule in an electronic triplet state
No full textThe triatomic spin-rovibronic variational code RVIB3 has been extended to include the effect of two uncoupled electrons, for both (3)Sigma(-) and (3)Pi (Renner-Teller) electronic states. The spin-orbital-rotational kinetic energy is included in the usual way, via terms (J+L+S). The phenomenological terms AL.S and lambda 2/3(3S(z)(2)) are introduced to reproduce the 3 spin-orbit and spin-spin splittings, respectively. Calculations are performed to evaluate the spin-rovibronic energy levels of CCO (X) over tilde (3) Sigma(-) and CCO (A) over tilde (3) Pi for which the Born-Oppenheimer potentials are derived from high-accuracy ab initio calculations
Nicholas Charles Handy. 17 June 1941 — 2 October 2012
No full textNicholas Handy made significant contributions in the applications of quantum mechanics to molecules. In an academic career at Cambridge University he was involved with many advances in the computational methods that have turned quantum chemistry into a central tool for understanding modern molecular science
Aesop Cop, Volume One
No full textThe back cover of this 40-page booklet speaks of an Aesop-inspired morality poem about notable crimes. Is that forward by Handy a deliberate play on the standard foreword? In it Handy, editor of tinytowntimes.com, a blog in Crawford's home town of Ithaca, NY, writes that Crawford chose to versify petty crimes of nominal import then added a quirky, often nonsensical, moral. For Handy it is the art of Stuhmiller that raises this book to art. Each of eighteen stories follows the same two-page format. On the left-hand page is a title and a police report. On the right-hand page is verse and moral set within a full-page illustration. These illustrations remind me of the chromolithographs of Walter Crane. The second story, Grand Farcery, is a good example. Its last lines are O! What a farce when we/Land on our arse and we/Get popped for grand larceny. The moral is Since all the world's a stage, always have an exit strategy. Among the more curious police reports is that in Play It Straight. The report here is of a subject walking strangely and carrying a cello case. Another caller reports finding a fork in her shower. My prize overall goes to The Russian Hairdresser's Boy Toy. All in all, this booklet represents one of the weirdest uses of Aesop's name that I have known.Franklin Crawford, Versifie
THE MULTIMODE APPROACH TO CHALLENGING PROBLEMS IN VIBRATION SPECTROSCOPY
No full textAuthor Institution: Department of Chemistry and Cherry L. Emerson Center for; Scientific Computation, Emory University, Atlanta, GA 30322; Dept. of Chemistry, University of Cambridge, Cambridge, UKI will briefly describe the code "MULTIMODE", developed in collaboration with Stuart Carter and Nicholas Handy, and then present applications to the series of molecules HO, HO and HO. I will also describe recent collateral work on developing full dimensional \textit{ab initio}-based potential energy surfaces for these molecules. Some comparisons with Diffusion Monte Carlo calculations done by Anne McCoy on these molecules will also be presented
Positivity and the quantization of physical systems : the c-shift' moment method, 1991
No full textThe Eigenvalue Moment Method (EMM) of Handy and Bessis is reformulated with special emphasis on the importance of positivity as a general quantization criterion
A theoretical study of plutonium diketone complexes for solvent extraction
No full textWe present a relativistic density functional study on some plutonium compounds with thenoyltrifluoroacetone and similar ligands which can be used in the extraction of plutonium. The method of effective core potentials is used on plutonium. The binding energies of the complexes of plutonium in the formal oxidation states II, IV and VI have been determined and the geometries of some of the complexes have been fully optimized. The stability of the compounds in the different oxidation states and the effect of varying the side groups in the ligands are discussed. Comparisons with analogous uranium compounds are presented
Distinguishing delivery and catalytic activity differences among G-protein deamidating protein toxins of the cytotoxic necrotizing factor (CNF) and Pasteurella multocida toxin (PMT) family through comparative analyses
No full textSubmission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-05-01The student, Nicholas Handy, accepted the attached license on 2025-05-01 at 11:16.The student, Nicholas Handy, submitted this Dissertation for approval on 2025-05-01 at 15:31.This Dissertation was approved for publication on 2025-05-02 at 10:29.DSpace SAF Submission Ingestion Package generated from Vireo submission #22150 on 2025-10-19 at 19:16:57AB toxins are a class of bacterial protein exotoxins characterized by a modular structure consisting of an 'A' active domain and a 'B' binding domain. These toxins are adept at delivering potent payloads into the cytosol of target cells, making them attractive candidates for Bacterial Toxin-Inspired Drug Delivery (BTIDD) platforms. This thesis focuses on a family of G-protein deamidating toxins, including Pasteurella multocida toxin and the cytotoxic necrotizing factor (CNF) family members, as models for investigating the structural and functional determinants for cytosolic cargo delivery. The diversity of this family, including the thirteen full-length homologs of the CNF toxin family, various CNF-like catalytic domains attached to different toxin systems, and the prevalence of the PMT N-terminal delivery motif throughout bacterial genomes offers a rich source for exploring the modularity and adaptability of AB toxins. A critical aspect of AB toxin-mediated delivery is the ability to escape endosomal degradation, a common challenge in cytosolic delivery of biologics. The CNF family is notable among AB toxins for the high homology yet distinct behaviors in binding, delivery, and activity among the studied homologs. The best studied CNF toxins, CNF1, CNF2, CNF3, and CNFy, all also have different responses to endosomal acidification. These studies found that modifying specific acidic amino acid residues in the CNFy translocation domain with those from CNF3 improved endosomal escape at higher pH levels, leading to more efficient cytosolic delivery. Furthermore, using small molecule inhibitors of the endosomal trafficking pathway, we showed that CNFy leaves the endosome at a later stage of the acidification process than CNF3, potentially leading to decreased efficiency in cargo delivery. These insights into the amino acid determinants of bacterial toxins can be leveraged to optimize the cytosolic delivery of biologic cargos using these toxins as BTIDD platforms. Once inside the cytosol, the CNF activity domains activate Rho GTPases through deamidation of a glutamine residue at the active site, with each CNF variant showing distinct substrate preferences. The data here shows that CNFx, a novel and phylogenetically distant member of the CNF family identified in cetain E. coli strains, modifies RhoA through transglutamination rather than deamidation, akin to the activity of dermonecrotic toxin (DNT). This unique activity profile of CNFx provided a valuable opportunity to study the structural determinants that differentiate these two reaction mechanisms catalyzed by these toxins. Our research identified critical active-site residues in CNFx that govern its enzymatic preference. We also identified a C-terminal cysteine residue that impeded cargo delivery, resulting in a higher EC50 value compared to other CNFs. The CNF family shares an N-terminal delivery vehicle with PMT, PMT-N. Previous studies in the laboratory by Nathan Clemons have shown that PMT-N is able to facilitate the entry of exogenous proteins, such as GFP, into the cytosol. However, the native PMT cargo domains, C1-C2-C3, require both C1 and C2 for the effective delivery of the catalytic C3 domain, indicating the presence of an accessory module that assists in cytosolic delivery. PMT-N homology is found in a wide range of bacterial genomes, linked to various C-terminal enzymatic motifs. This suggests a role for the accessory module in adapting cargo to the PMT-N delivery vehicle. Through luciferase reporter assays, we show that the CNFs also require an accessory module for delivery of their cargo domains, though a significantly smaller region than for PMT is required to restore delivery. The presence of accessory modules in PMT-like delivery systems suggests a promising strategy for improving the delivery of diverse cargos. These results offer an understanding of the amino acid sequence characteristics of bacterial toxins that can be leveraged to improve the cytosolic delivery of biological cargos using BTIDD platforms
On the resolution of identity Coulomb energy approximation in density functional theory
No full textThe Resolution of the Identity approximation for the Coulomb (RI-J) energy in Density Functional Theory improves the computational efficiency of large-scale calculations but requires the use of a second, or "auxiliary" basis set. We examine the performance of some of the existing auxiliary basis sets with a variety of basis sets and molecules. We determine the accuracy of the RI-J approximation for these basis sets and suggest criteria for the selection of combinations of basis set and auxiliary basis set
A theoretical spectroscopy study of the X3Sigma- and the A3Pi states of the C2S radical
No full textThe spin-rovibronic levels for the X3Sigma-,A3P electronic system of C2S are calculated variationally, using ab initio potential energy surfaces and taking into account the non-adiabatic coupling between the two states. The energies of selected levels with Sigma and Pi vibronic symmetry, up to approx16500 cm-1, are reported and compared with available experimental data
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