86 research outputs found

    Electronic Thesis and Dissertation Information Session

    Get PDF
    This information session walked graduate students through the process of submitting a thesis/dissertation. Representatives from the Graduate School and UK Libraries were present to answer questions

    University of Kentucky Thesis and Dissertation Submission Guide

    Get PDF
    This guide walks University of Kentucky graduate students through the steps of submitting their theses or dissertations to the UKnowledge repository. The latest version was updated on February 5, 2021

    Quantum analysis of the nondegenerate optical parametric oscillator with injected signal

    Get PDF
    In this paper we study the nondegenerate optical parametric oscillator with injected signal, both analytically and numerically. We develop a perturbation approach which allows us to find approximate analytical solutions, starting from the full equations of motion in the positive P-representation. We demonstrate the regimes of validity of our approximations via comparison with the full stochastic results. We and that, with reasonably low levels of injected signal, the system allows for demonstrations of quantum entanglement and the Einstein-Podolsky-Rosen paradox. In contrast to the normal optical parametric oscillator operating below threshold, these features are demonstrated with relatively intense felds.Comment: 26 pages, 7 figure

    Theoretical description of hydrogen bonding in oxalic acid dimer and trimer based on the combined extended-transition-state energy decomposition analysis and natural orbitals for chemical valence (ETS-NOCV)

    Get PDF
    In the present study we have analyzed hydrogen bonding in dimer and trimer of oxalic acid, based on a recently proposed charge and energy decomposition scheme (ETS-NOCV). In the case of a dimer, two conformations, α and β, were considered. The deformation density contributions originating from NOCV’s revealed that the formation of hydrogen bonding is associated with the electronic charge deformation in both the σ—(Δρσ) and π-networks (Δρπ). It was demonstrated that σ-donation is realized by electron transfer from the lone pair of oxygen on one monomer into the empty \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}ρHO \rho_{H - O}^* \end{document} orbital of the second oxalic acid fragment. In addition, a covalent contribution is observed by the density transfer from hydrogen of H-O group in one oxalic acid monomer to the oxygen atom of the second fragment. The resonance assisted component (Δρπ), is based on the transfer of electron density from the π—orbital localized on the oxygen of OH on one oxalic acid monomer to the oxygen atom of the other fragment. ETS-NOCV allowed to conclude that the σ(O---HO) component is roughly eight times as important as π (RAHB) contribution in terms of energetic estimation. The electrostatic factor (ΔEelstat) is equally as important as orbital interaction term (ΔEorb). Finally, comparing β-dimer of oxalic acid with trimer we found practically no difference concerning each of the O---HO bonds, neither qualitative nor quantitative

    An exceptional horizontal gene transfer in plastids: gene replacement by a distant bacterial paralog and evidence that haptophyte and cryptophyte plastids are sisters

    Get PDF
    BACKGROUND: Horizontal gene transfer (HGT) to the plant mitochondrial genome has recently been shown to occur at a surprisingly high rate; however, little evidence has been found for HGT to the plastid genome, despite extensive sequencing. In this study, we analyzed all genes from sequenced plastid genomes to unearth any neglected cases of HGT and to obtain a measure of the overall extent of HGT to the plastid. RESULTS: Although several genes gave strongly supported conflicting trees under certain conditions, we are confident of HGT in only a single case beyond the rubisco HGT already reported. Most of the conflicts involved near neighbors connected by long branches (e.g. red algae and their secondary hosts), where phylogenetic methods are prone to mislead. However, three genes – clpP, ycf2, and rpl36 – provided strong support for taxa moving far from their organismal position. Further taxon sampling of clpP and ycf2 resulted in rejection of HGT due to long-branch attraction and a serious error in the published plastid genome sequence of Oenothera elata, respectively. A single new case, a bacterial rpl36 gene transferred into the ancestor of the cryptophyte and haptophyte plastids, appears to be a true HGT event. Interestingly, this rpl36 gene is a distantly related paralog of the rpl36 type found in other plastids and most eubacteria. Moreover, the transferred gene has physically replaced the native rpl36 gene, yet flanking genes and intergenic regions show no sign of HGT. This suggests that gene replacement somehow occurred by recombination at the very ends of rpl36, without the level and length of similarity normally expected to support recombination. CONCLUSION: The rpl36 HGT discovered in this study is of considerable interest in terms of both molecular mechanism and phylogeny. The plastid acquisition of a bacterial rpl36 gene via HGT provides the first strong evidence for a sister-group relationship between haptophyte and cryptophyte plastids to the exclusion of heterokont and alveolate plastids. Moreover, the bacterial gene has replaced the native plastid rpl36 gene by an uncertain mechanism that appears inconsistent with existing models for the recombinational basis of gene conversion

    Passive Q-switching and mode-locking for the generation of nanosecond to femtosecond pulses

    Full text link

    Sex differences in venous stenosis and occlusion in patients with endocardial leads

    No full text
    Venous stenosis and occlusion (VSO) in the presence of endocardial leads constitute one of the complications of permanent cardiac pacing. At present there are no scientific reports on the influence of sex on the incidence of VSO. Aim The aim of the study was to examine the influence of sex on the incidence of VSO in patients with earlier implanted endocardial leads in a single-center retrospective analysis. Materials and methods The material consists of 284 records of consecutive patients admitted to hospital to undergo electrotherapy procedures. In all patients a contrast venography for ipsilateral venous confluence was performed before the procedure. Patients were divided into two groups according to sex criterion. Groups were compared concerning following parameters: demographic characteristics, cardiac implantable electronic device (CIED) characteristics, comorbidities, CHA2DS2-VASc score, selected risk factors for VSO. Results Group I consist of 101 females, whereas group II consist of 183 males. Both groups did not differ significantly for age, number of implanted endocardial leads and lead dwell time. In the cohort males were with significantly greater burden of morbidity, reflected by the mean result of CHA2DS2-VASc (P=0.0098). In males there was significantly more often chronic heart failure (P<0.0001), chronic obstructive pulmonary disease (P=0.0450) and tobacco use (P=0.0159). Males had more ICD implanted than females (P=0.0270). In the examine cohort 88 patients (31%) had VSO. There was no statistically significant difference in terms of presence of VSO between females and males (P=0.4685). The detailed analysis of the patients with VSO divided according to sex revealed higher morbidity in males. Conclusions The equality of VSO incidence in groups of males and females along with the predominance of factors protecting against VSO in group of males support the assumption that female gender is a protective factor against the development of VSO, equally as known protective factors in males

    The analysis of indications and early results of transvenous lead extraction in patients with a pacemaker, ICD and CRT - single-centre experience

    No full text
    Introduction: Transvenous lead extraction (TLE) is a recognized method of treatment in the case of permanent stimulation complication. Objectives: The objective of this study was to analyse the indications and presentation of the early experience of TLE procedures in a group of patients with old pacing systems. Patients and methods: Patients with a relevant history of stimulation (at least 12 months in case of a pacemaker) qualified for the research. Indications, effectiveness and complications of TLE procedures were analysed. Results: Two hundred patients at the age of 66.4 (19.1-86.2 years) were enrolled and 278 leads with dwell time 76.2 months (2.1-327.4) were removed. The indications for TLE were: lead-dependent infective endocarditis in 13 cases (6.5%), pocket infection in 29 cases (14.5%), lead damage in 120 cases (60.0%), and upgrade of device system in 38 cases (19.0%). Manual traction was used to remove 66 active fixation leads (23.7%). A femoral approach was required to extract 4 leads (1.4%). Two hundred and eight leads (74.8%) were extracted using the mechanical (Cook) system and subclavian approach. Laser technique, and an electrosurgical sheath were not used. Complete procedural success was achieved in 96% of cases and overall clinical success was 98.5%. Complication rate was 5.5% (11 patients): minor and major complication rate was 3.0% (6 patients) and 2.5% (5 cases), respectively. Low body mass index (BMI) was associated with a higher rate of complications. Conclusions: The dominant indication to TLE procedures was lead dysfunction. Transvenous lead extraction has a high success rate and a low complication rate. Low BMI increased the complication rate
    corecore