The paper presents a study of a large-area field emitter based on a composite of vertically aligned carbon nanotubes covered with a continuous and conformal layer of nickel oxide by the atomic layer deposition method. The arrays of carbon nanotubes were grown by direct current plasma-enhanced chemical vapor deposition on a pure Si substrate using a nickel oxide catalyst which was also deposited by atomic layer deposition. The emission characteristics of an array of pure vertically oriented carbon nanotubes with a structure identical in morphology, covered with a layer of thin nickel oxide, are compared using the data from a unique computerized field emission projector.
View Article and Find Full Text PDFBackground: Familial breast cancer is associated with mutations in several genes (BRCA1, BRCA2, p53, ATM) whose protein products protect against radiation-induced genotoxicity. This study tested whether sporadic breast cancer was associated with constitutive radiation hypersensitivity.
Methods: Blood lymphocytes and EBV-transformed lymphoblasts from patients with newly diagnosed breast cancer and controls without cancer were evaluated for ionizing radiation (IR)-induced chromosomal aberrations and cell cycle delays.
DNA topoisomerase II is required in the cell cycle to decatenate intertwined daughter chromatids prior to mitosis. To study the mechanisms that cells use to accomplish timely chromatid decatenation, the activity of a catenation-responsive checkpoint was monitored in human skin fibroblasts with inherited or acquired defects in the DNA damage G2 checkpoint. G2 delay was quantified shortly after a brief incubation with ICRF-193, which blocks the ability of topoisomerase II to decatenate chromatids, or treatment with ionizing radiation (IR), which damages DNA.
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