Publications by authors named "R R Swiger"

A new rapid DNA solution, the RapidHIT ID, can accommodate two different sample cartridges, ACE, for the analysis of a single swab and EXT, for the analysis of DNA extracts. An efficient internal validation designed for low-throughput rapid DNA is described. An evaluation of the EXT sample cartridge is also described.

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Three two-photon absorption (2PA) dyes (donor-π-donor (DPA2F), donor-π-acceptor (AF240), and acceptor-π-acceptor (BT2F); specifically, D is Ph2N-, A is 2-benzothiazoyl, and the π-linker is 9,9-diethylfluorene) are examined in a variety of aprotic solvents. Because the 2PA cross section is sensitive to the polarity of the local environment, this report examines the solvent-dependent linear photophysics of the dyes, which are important to understand before probing more complex solid-state systems. The symmetrical dyes show little solvent dependence; however, AF240 has significant solvatochromism observed in the fluorescence spectra and lifetimes and also the transient absorption spectra.

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This chapter describes the use of the bacteriophage cII positive selection somatic mutational assay with the Muta™Mouse transgenic model system. The assay is similar to others involving a transgenic target, including the cII and lacI assays in the Big Blue(®) Mouse, lacZ in the MutaMouse, and the gpt delta assay. Briefly, high-molecular-weight DNA is purified from the tissue of interest and used as substrate during in vitro packaging reactions, where the λ transgenes are excised from the genome and assembled into viable phage.

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Spin-cast films of dyes (donor-π-donor, donor-π-acceptor, and acceptor-π-acceptor type, where the donor is Ph2N-, the acceptor is 2-benzothiazoyl, and the π-linker is 9,9-diethylfluorene) blended with nonconjugated bisphthalimides were prepared. Upon visible-light excitation of the dyes, quenching of the excited state occurs by exciplex formation between dye and bisphthalimide molecules or, in some cases, by excimer formation or aggregation-induced emission between two dye molecules. The extent of exciplex formation is dependent on the driving force, which can be calculated using the energy difference between the lowest unoccupied molecular orbitals (LUMOs) of the dyes and bisphthalimides.

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The effect of plasmonic enhancement on the two-photon absorption cross section of organic chromophores attached to polyelectrolyte-coated gold nanorods was investigated. The magnitudes of such enhancements were confirmed using single and two photon excitations of the chromophore molecules bound to polyelectrolyte-coated gold nanorods. By synthesizing two-, four-, six-, and eight-polyelectrolyte layer coated nanorods of a particular aspect ratio, the distance dependence of the evanescent electromagnetic field on molecular two-photon absorption was observed.

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