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Gregory A Parker

Publications and source records attributed to Gregory A Parker.

3 recordsLinked to original sources

General laser interaction theory in atom-diatom systems for both adiabatic and nonadiabatic cases.

This paper develops the general theory for laser fields interacting with bimolecular systems. In this study, we choose to use the multipolar gauge on the basis of gauge invariance. We consider both the adiabatic and nonadiabatic cases and find they produce similar interaction pictures. As an application of this theory, we present the study of rovibrational energy transfer in Ar + CO collisions in the presence of an intense laser field.

Journal Article↗

Conical intersection between the lowest spin-aligned Li3(4A') potential-energy surfaces.

We have calculated new potential-energy surfaces for the lowest two spin-aligned (4)A(') states of the Li(3) trimer. This calculation shows a seam of conical intersections between these states resulting from the extra symmetry of the system when the atoms are in a collinear arrangement. This seam is especially important because of its proximity to the three-body dissociation limit of the system; ultracold scattering calculations and the bound-state energies of the system will be affected by the presence of this conical intersection. In this paper we discuss the calculation of the potential-energy surface and the location of the conical intersection seam.

Journal Article↗

A phase II trial of weekly paclitaxel, 5-fluorouracil, and leucovorin as first-line treatment for metastatic breast cancer.

PURPOSE: This phase II multicenter trial evaluated the efficacy and toxicity of weekly paclitaxel, 5-fluorouracil, and leucovorin administered as first-line therapy for metastatic breast cancer. PATIENTS AND METHODS: The study enrolled 155 women with pathologically confirmed and measurable metastatic adenocarcinoma of the breast. Treatment consisted of paclitaxel 80 mg/m2, 5-fluorouracil 425 mg/m2, and leucovorin 20 mg/m2 administered weekly 4 x per 4-week cycle in the first 40 patients enrolled (group 1), and weekly 3 x per 4-week cycle in the subsequent 115 patients (group 2) enrolled. Hematologic growth factor support was not routinely used. Twenty patients with hepatic dysfunction were enrolled to assess the tolerability of the regimen in this population. All therapies were delivered in an outpatient setting. RESULTS: The overall response rate was 48%, with 12-month estimated survival rates of 53% and 65% for treatment groups 1 and 2, respectively. Response rates were not statistically different between the two treatment schedules. Therapy was well tolerated when delivered on the every 3 of 4-week schedule, including patients with hepatic involvement and those age > or = 65. CONCLUSION: Weekly therapy with paclitaxel and 5-fluorouracil with leucovorin is active as first-line therapy for metastatic breast cancer. Use of this regimen should be given consideration, particularly in patients who are not candidates for anthracycline-based therapy.

Adenocarcinoma↗