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A STATIC SCREENED POTENTIAL METHOD FOR THE CALCULATION OF ELECTRONIC TRANSITION PROPERTIES OF AZABENZENESUnknown Date (has links)
The calculation of electronic properties of conjugated molecules is a problem of great interest in many areas of current research. We have developed a method based on using the static screened potential within the combined formalism of Green function theory and density response theory and apply this method to the calculation of electronic transition properties of a series of azabenzenes: pyridine, pyrazine, pyrimidine, pyridazine, s-triazine, as-triazine, and v-triazine. / This method consists of three basic stages of calculation. The first stage consists of a Pariser-Parr-Pople calculation using the Mataga-Nishimoto approximation for the potential. This produces a set of zero order molecular orbitals and energies which serve as input into the second stage of the method. The first step in this stage is the calculation of the free propagator from which, using techniques from diagrammatic perturbation theory, the dressed polarization propagator is obtained. This dressed propagator is calculated within the RPA with only diagonal exchange terms included and based on two different expansion: one is in terms of the singlet vertex function and the other in terms of the triplet vertex function. Using this we then calculate the static screened potential in three different ways. The first is based just on the free propagator while the other two are based on the two different dressed propagators calculated. Once these potentials are obtained we then return to stage 1 and re-iterate the PPP calculation using the static screened potentials in place of the Mataga-Nishimoto potential. This entire process is then repeated until the static screened potentials become self-consistent. From these self-consistent potentials molecular orbitals, energies, and generalized bond orders are obtained. These molecular orbitals and energies along with the self-consistent static screened potentials themselves serve as input into the equations of stage 3. It is here that transition energies and oscillator strengths are calculated according to either the RPA or the TDA and these final calculated quantities are compared as to their relative value depending on the type of approximations employed in order to make some qualitative assessment of their usefulness. / Source: Dissertation Abstracts International, Volume: 42-06, Section: B, page: 2424. / Thesis (Ph.D.)--The Florida State University, 1981.
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Role of 3' end in regulation of mouse histone gene expressionUnknown Date (has links)
Sequences at both 5$\sp\prime$ and 3$\sp\prime$ ends of mouse histone genes contribute to the expression of the gene. The effect of 5$\sp\prime$ sequences of H2a(614) and H3.2(614) is presumably on the rate of transcription. The 3$\sp\prime$ sequences required for high expression of the mouse H2a(614) gene are the same as the sequences required for 3$\sp\prime$ end formation. When these sequences are substituted for the 3$\sp\prime$ end of the poorly expressed H2a(291) gene, the expression of the H2a(291) gene is increased 5-fold. A 65 nucleotide fragment containing the H2a(614) 3$\sp\prime$ processing signal increases the expression of the H2a(291) gene when it is placed in the proper orientation downstream of the H2a(291) 3$\sp\prime$ end, suggesting that the transcript is sequentially processed. In in vitro processing experiments, the different histone 3$\sp\prime$ ends show different processing efficiencies which correlate with the expression in cells. This hairpin loop structure has multiple uses which include transcription termination, mRNA stability and efficiency of processing by the cell to regulate the steady-state level of histone mRNAs. / Source: Dissertation Abstracts International, Volume: 50-05, Section: B, page: 1785. / Major Professor: William F. Marzluff. / Thesis (Ph.D.)--The Florida State University, 1989.
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Expression of chimeric small nuclear-RNA-histone genesUnknown Date (has links)
RNA polymerase II transcribes all mRNAs as well as several of the small nuclear RNA (snRNA) genes. Among RNA pol II genes, the U1 snRNA genes and replication dependent histone genes are distinct in their lack of intervening sequences and polyadenylated 3$\sp\prime$ ends. A unique feature of the U1 gene is that U1 3$\sp\prime$end formation requires an snRNA promoter. The promoters used in those experiments were for genes that normally form polyadenylated mRNAs. I constructed chimeric mouse histone-U1 genes to see if the U1 3$\sp\prime$end would be used when coupled to a promoter from a non-polyadenylated transcript. Using an S1 nuclease assay I showed that the transcripts do not form the U1 3$\sp\prime$end, but end at heterogeneous sites, implying that the pol II-histone transcription complex lacks a U1-specific 3$\sp\prime$end-forming activity. / It has also been reported that the transcripts initiating from U1 promoters do not direct synthesis of polyadenylated mRNA. I also constructed chimeric mouse U1-histone genes and showed that U1 promoters with at least 5 base pairs of the coding sequence highly express the histone mRNA. Transcripts of these chimeric genes mapped to the normal U1 start and formed normal histone 3$\sp\prime$ends. / When I combined these genes to make UHU genes (U1 promoter, histone coding, U1 3$\sp\prime$end), 50% of the RNAs had U1 3$\sp\prime$ends, and the other 50% were readthrough transcripts with heterogeneous ends. When I added the histone 3$\sp\prime$end to the UHU gene to make UHUH and UHHU genes, most transcripts had histone ends and were translated efficiently. Experiments comparing the stability and relative amounts of UHU and UHUH RNAs showed that a downstream histone end did not affect the efficiency of U1 3$\sp\prime$end formation, suggesting that U1 3$\sp\prime$ ends are formed by transcription termination, unlike any other pol II genes. When the distance between the U1 promoter and U1 3$\sp\prime$ end was shortened to 146, more U1 ends were formed than histone ends, demonstrating that the coupling of the U1 promoter and U1 3$\sp\prime$ end formation is distance dependent. Long UHUH transcripts with histone ends were transported to the cytoplasm and efficiently translated whereas transcripts of a similar length with U1 ends may have never left the nucleus. This suggests that the histone 3$\sp\prime$ end functions either as a signal for transport from the nucleus to the cytoplasm or as a signal for efficient translation. / Source: Dissertation Abstracts International, Volume: 51-09, Section: B, page: 4195. / Major Professor: William F. Marzluff. / Thesis (Ph.D.)--The Florida State University, 1990.
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Cloning and characterization of satellite 2 hammerheads from a diverse set of caudate amphibiansUnknown Date (has links)
Satellite 2 is a 300-350 bp tandemly repeated DNA that is highly conserved in different salamander families. While the function of satellite 2 is not known, it has the ability to promote transcription using a self-contained snRNA type of promoter and its transcripts can catalyze their own site-specific cleavage using an extended hammerhead domain. An analysis of chimeric hammerheads indicated that the different stem I extensions were active only in the context of compatible stem II regions. To investigate this compatibility requirement, partial satellite 2 sequences containing the extended hammerhead domain were cloned and characterized from six species representing four Caudate families. Results indicated that satellite 2 elements exist in every Caudate family except Sirenidae. Despite differences in the abundance of this element and its transcripts, the tandemly repeated genomic organization and the tissue specific transcript patterns have been conserved. Comparison of the satellite 2 sequences from different species suggested the existence of at least two groups, and they might evolve at different rates in different families. Sequence analysis also revealed that the species consensus sequence is under selection while individual repeats are free to diverge. However, this selection is not for increasing the cleavage ability of its extended hammerhead. Although each species consensus sequence can form an extended hammerhead that has the same central core and the same secondary structure, these extended hammerheads have very different in vitro cleavage rates. Since the differences are primarily in the stem I and stem II regions, the results suggest that both regions are important for self-cleavage. / Source: Dissertation Abstracts International, Volume: 56-07, Section: B, page: 3611. / Major Professor: Lloyd M. Epstein. / Thesis (Ph.D.)--The Florida State University, 1995.
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THE TOTAL SCATTERING CROSS-SECTIONS FOR THE SYSTEMS (NORMAL)HYDROGEN + (NORMAL)HYDROGEN, PARA-HYDROGEN + PARA-HYDROGEN, (NORMAL)DEUTERIUM + (NORMAL)DEUTERIUM, ORTHO-DEUTERIUM + ORTHO-DEUTERIUM AND HYDROGEN-DEUTERIDE + HYDROGEN-DEUTERIDE FOR RELATIVE ENERGIES BELOW TEN MILLI-ELECTRON VOLTSUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-06, Section: B, page: 2725. / Thesis (Ph.D.)--The Florida State University, 1979.
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MEASUREMENT OF THE SECOND VIRIAL COEFFICIENT OF THE LORENTZ-LORENZ FUNCTION OF NOBLE GASESUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-12, Section: B, page: 7234. / Thesis (Ph.D.)--The Florida State University, 1972.
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AN ASYMPTOTIC THEORY FOR STEADY SOURCE EXPANSION OF A BINARY GAS MIXTUREUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-11, Section: B, page: 6570. / Thesis (Ph.D.)--The Florida State University, 1971.
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A HIGH-RESOLUTION INFRARED STUDY OF SEVEN INTERACTING BANDS OF FORMALDEHYDE IN THE C-H STRETCHING REGIONUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 38-06, Section: B, page: 2734. / Thesis (Ph.D.)--The Florida State University, 1976.
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MEASUREMENT OF ABSOLUTE TOTAL SCATTERING CROSS-SECTIONS FOR THE SYSTEMS NEON - NEON, ARGON - ARGON, NITROGEN - NITROGEN, AND OXYGEN - OXYGEN USING CROSSED NOZZLE BEAMS IN THE THERMAL ENERGY RANGEUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 33-02, Section: B, page: 0858. / Thesis (Ph.D.)--The Florida State University, 1972.
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CHEMICAL ACCELERATOR FOR PRODUCING A VARIABLE-ENERGY NEUTRAL MOLECULAR BEAM: TOTAL CROSS-SECTIONS FOR SULFUR HEXAFLUORIDE ON MOLECULAR HYDROGEN, ATOMIC HELIUM, CARBON DIOXIDE, AND SULFUR HEXAFLUORIDEUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 35-02, Section: B, page: 0980. / Thesis (Ph.D.)--The Florida State University, 1974.
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