Katherine C. Roth

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Far Ultraviolet Spectroscopic Explorer spectra of the white dwarf stars G191-B2B, GD 394, WD 2211Ϫ495, and WD 2331Ϫ475 cover the absorption features out of the ground electronic states of N i, N ii, N iii, O i, and Ar i in the far-ultraviolet, providing new insights on the origin of the partial ionization of the local interstellar medium (LISM) and, for the(More)
Despite a rich phenomenology, gamma-ray bursts (GRBs) are divided into two classes based on their duration and spectral hardness--the long-soft and the short-hard bursts. The discovery of afterglow emission from long GRBs was a watershed event, pinpointing their origin to star-forming galaxies, and hence the death of massive stars, and indicating an energy(More)
The final chapter in the long-standing mystery of the gamma-ray bursts (GRBs) centres on the origin of the short-hard class of bursts, which are suspected on theoretical grounds to result from the coalescence of neutron-star or black-hole binary systems. Numerous searches for the afterglows of short-hard bursts have been made, galvanized by the revolution(More)
We report the detection of the λ1560 and λ1657 ground-state C I absorption features in the z abs = 1.6748 system toward the QSO PKS 1756+237. We find no associated C I* lines with a resulting 3 σ excitation temperature upper-limit of T ex ≤ 8.54 (+0.65, −0.56) K, which is consistent with the predicted CMBR temperature of T CMBR = 7.291 K. Because the(More)
Our aim was to establish the frequency and the longitudinal pattern of MAC culture positivity in late stage HIV-infected patients. Two other aims were to analyse risk factors for progression from localized to systemic disease and the value of PCR diagnosis using blood specimens. A total of 107 patients were recruited to be followed for 32 weeks. Prior MAC(More)
Here we report successful interferometric coupling of two large telescopes with single-mode fibers. Interference fringes were obtained in the 2- to 2.3-micrometer wavelength range on the star 107 Herculis by using the two Keck 10-meter telescopes, each feeding their common interferometric focus with 300 meters of single-mode fibers. This experiment(More)
Twenty-one human immunodeficiency virus (HIV) seropositive patients were studied to determine the prevalence of cervical dysplasia, the distribution of human papilloma virus (HPV) subtypes, and the utility of cytologic diagnosis in this population. The patients ranged in age from 18 to 41 years. HIV infection was diagnosed in all patients by ELISA method(More)
We reviewed the cases of 95 children with duplex ureteroceles treated in this department over an 18-year period. There were 101 ureteroceles (6 bilateral). Diagnosis and treatment were analyzed. Special attention was paid to newborns screened in utero. We always strove to preserve functional renal tissue whenever possible. In keeping with this goal, three(More)
BACKGROUND Although familial susceptibility to glioma is known, the genetic basis for this susceptibility remains unidentified in the majority of glioma-specific families. An alternative approach to identifying such genes is to examine cancer pedigrees, which include glioma as one of several cancer phenotypes, to determine whether common chromosomal(More)