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No description available.

The non-random covalent binding to DNA by the intercalators 8-azido-ethidium, 7-azido-actinomycin D, anti-(+)-benzo (a) pyrene 7,8-diol 9,10-epoxide, and anti-($-$)-benzo (a) pyrene 7,8-diol 9,10-epoxide was investigated using techniques analogous to DNA sequencing. A computer-assisted methodology was subsequently developed that allowed the characterization of all sequence preferences of covalent binding up to the quartet level. All intercalators exhibited some preferences in binding. 7-azido-actinomycin D was most sequence selective and 8-azido-ethidium was least sequence selective. Next-nearest neighboring bases exert a major influence on the reactivities of the intercalators. The magnitude of the next-nearest neighbor influence is almost as great as the nearest-neighbor influence. There were certain sequence preferences of covalent binding shared by all intercalators. The sequence preference analysis indicated that 7-azido-actinomycin D and 8-azido-ethidium were excellent probes for evaluating the reversible binding of the parent actinomycin D and ethidium molecules. There were some differences in the sequence preferences of covalent binding by the two benzo (a) pyrene diol epoxide enantiomers. The potent carcinogenicity of the anti-(+)-isomer may be caused by the adduct at the exocyclic amine of guanine bases, since this isomer forms more of these adducts than the anti-($-$)-isomer. / Source: Dissertation Abstracts International, Volume: 51-07, Section: B, page: 3284. / Major Professor: Randolph L. Rill. / Thesis (Ph.D.)--The Florida State University, 1990.

Single cocrystals of adenosine:5-iodouracil and partially deuterated adenosine:5-iodouracil were irradiated at 4.2K, 77K, and 300K with X-rays from a 3Mev Van de Graaff electron accelerator. Several types of free radicals were produced by the radiation and were studied by X-Band and Q-Band ESR from 77K to 300K. Six radicals were identified. Two electron addition products (radicals I1 and As1) and one electron abstraction product (radical I2) are stabilized at 77K. At room temperature two hydrogen addition radicals (I3 and As2) and a "singlet" radical (As3) are stabilized. Upon annealing to 165K after low temperature irradiation, radicals I1 and I2 decay to nonparamagnetic species. Radical As1 remains stable from 77K to 240K. From 240K to 300K the As1 radical decays and radicals As2 and I3 gradually grow in. Irradiation and observation at room temperature produces predominantly a "singlet" radical (As3). The electron addition radical, I1, is a (sigma)*-type radical that presents the unpaired electon spin density localized mainly on the iodine atom. This radical does not de-halogenate, to produce the reactive uracilyl radical, but instead it decays into a non paramagnetic species when annealed from 77K to 300K. The low temperature radical population obtained in this cocrystal and the subsequent radical reactions upon annealing, contradict the hypothesis that, in the presence of purine:pyrimidine stacking interactions, electrons are transfered to the pyrimidines while holes are transfered to the purines. / Source: Dissertation Abstracts International, Volume: 47-05, Section: B, page: 2043. / Thesis (Ph.D.)--The Florida State University, 1986.

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The topic of this dissertation is on the design and construction of miniature microscope objective optics. The design of miniature microscope objective is both similar and different from conventional microscope objective. The design and construction of two miniature microscope objectives are presented in this dissertation. The first one is a high numerical aperture (NA), water-immersion objective and it is a part of a fiber confocal reflectance microscope (FCRM). The second one is a moderate NA dry objective and it is a part of a miniature microscope array (MMA). The capability, complexity and fabrication method of the two miniature objectives are different but they both share some similar design traits as result of their miniaturization. FCRM's miniature objective has a NA of 1.0 and it is designed to operate at near infrared lambda = 1,064 nm. It is 7 mm in outer diameter and 21 mm in length (measured from object plane to image plane). This kind of dimension is approximately 10 times smaller than a conventional microscope objective of similar caliber. Sub-micrometer resolution has been experimentally demonstrated with this miniature objective. MMA's miniature objective has a NA of 0.4 and it is designed to operate over the visible spectrum. It is 1.2 mm in diameter and 9.4 mm in length. The image quality of MMA's miniature objective is experimentally demonstrated to be comparable to the state-of-art commercial microscope objective.

The topic of dissertation is on the development of a miniature imaging device named as multi-modal miniature microscope [a.k.a. 4M Device]. Generally speaking, the development of an optical imaging device involves three main processes: optical design, fabrication and metrology. They are interdependent and often comprise a feedback loop. This dissertation will address these three processes sequentially. The 4M device is miniature compound microscope consisting of miniature optics, electronic imaging device, and mechanical device. Every component is integrated on single silicon substrate. The main purpose of 4M device is to provide an imaging capability for the detection of pre-cancer without biopsy. It uses a novel optics called hybrid lens that is fabricated by using a grayscale photomask and photolithographic technique. The hybrid lens is made of sot-gel material and glass substrate. It has 1.2mm of diameter and its surface is conic. Given lens design constraints from the fabrication, the series of lens design for 4M device are implemented and presented. Each design delivers diffraction-limited imaging performance with N.A ranging from 0.4 to 0.7. The 4M device that is currently built has 0.4 of N.A. The imaging quality assessments of 4M device are also implemented in quantitative and qualitative ways. There are two instruments for imaging quality assessment: Multi-modal imaging testbed for entire imaging device and Shack-Hartmann wavefront sensor for individual element. The qualitative assessment includes multi-modal imaging experiments under different illumination modes. The object is a cervical cancer cell prepared by Dr. Kortum's Group at Univ. of Texas at Austin. The qualitative assessment includes the surface characterization and wavefront measurement of individual optics and the MTF measurement of entire device. The results of imaging quality assessment show the potential of 4M device for medical imaging device. They also explain the degradation of imaging quality.

We present an inverse model to decompose bulk fluorescence spectra and extract tissue biological parameters. By deconvolving the effects of absorption and scattering from measured spectra, we are able to extract the intrinsic contributions from cellular and stromal fluorophores. Ovarian fluorescence, acquired ex-vivo immediately upon removal from patients, are analyzed using this model. We test the validity of the inverse model, and show that it has the ability to improve our understanding of the biological changes that cause the observed differences in the fluorescence spectra. The outputs of the model are used to develop classifiers for tissue diagnosis. Classifiers based on PLS selected features are also developed. An accuracy of more than 93% for discrimination between normal and cancerous ovarian tissues is achieved.