4 resultados para Carbonate radical
em Brock University, Canada
Resumo:
Thesis (M.Sc.)--Brock University, 2004.
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The purpose of this study was to determine whether there was any evidence of psychosexual morbidity among men who experienced radical radiation treatment for prostate cancer. With relatively little known or available retrospective data on the psychosexual implications of radical radiation treatment in men with prostate cancer, this study posited eight research questions which provided the basis for the research. Fifty men from Southern Ontario, between the ages of 52 to 78 years, were included in the study. They had been previously randomized to a clinical trial comparing radical radiation therapy by external beam radiation, or radical radiation using a combination of a temporary iridium implant plus external beam radiation, for localized or locally advanced prostate cancer. Assessment of sexual functioning, drive, attitudes, body image, and sexual satisfaction was drawn from a multidimensional approach, since psychosexuality was viewed as having an impact on biological, psychological, and sociological domains of functioning. Medical chart reviews, semi-structured interviews, demographical profiles of each participant, and the Derogatis Sexual Functioning Inventory (DSFI) were the methods used to collect data over a four-month period. Both quantitative and qualitative research methods were incorporated in the design and evaluation of the study. Frequencies, contingency analysis, Pearson's coefficient of correlation, t-tests, and ANOVA comprised the quantitative analysis. Data obtained from audio-taped interviews were analyzed qualitatively, and used for offering further insight and for facilitating the quantitative aspect of the analysis. Overall, there was sufficient evidence to suggest psychosexual morbidity among men who were treated with radiation therapy for prostate cancer. As well,there were a number of significant findings available to answer all of the posited research questions. The most significant findings were noted in post-treatment erectile ability and sexual activity. A post-treatment change in erectile ability was reported by eighty percent of men. Sixty percent of men noted a decrease in their ability to achieve an erection by reporting some morning stiffness only, penile rigidity insufficient for penetration, decreased control of erection, and loss of spontaneous erection. Other contributing factors associated with change in erectile status were: pain or altering sensation of orgasm, blood in ejaculate, pain and decreased amount of ejaculate, and penile numbness or pain. Eighty-two percent of men experienced a post-treatment change in sexual function, primarily due to the impact of decreasing erectile status. Only seven men reported that they experienced a decrease in desire mentally, whereas the vast majority did not experience any change in desire. Changes in foreplay, stress with optimal sexual positioning, and reduced spontaneity of sex, were other factors reported with the changes in sexual activity. The findings in this study broaden our understanding of what middle- to later-aged men feel and experience as they venture onward following treatment. This was the first study that evaluated available prospective data on pre-treatment erectile status and sexual activity. As well, this study was the first (with participant compliance rates of 100 percent) to have included an interview format to capture the views of such a large number of men. This study concluded with recommendations and implications for future research and practice as we move in the direction of understanding what is necessary for preserving psychosexual well being and enhancing quality of life in men treated with radiation therapy for prostate cancer.
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North Amerlc8 W8S inundated by fJ major eplcontlnental sea during ihe C:retaceo.us Period. The sOljihw6rd transgression of th.e northern Boreal See along the ~\festern Interior Seaway resulted in a meetlng with the northward edv6nclng waters from the GUlf of Mexico (Obradovich and Cobban, 1975). Th1s link was 1n eXlstence by late Albien time and 6llowed for the comm1ngl1ng of the prol1ferous Arctic and Gulf rnar1ne faunas (F1g. 1). By early Campanlan time, there was a widening of B6ffln Bay wlth a slrnult8neous subsidence 1n the Arct1c Archlpelago and Sverdrup 6as1n (W11liam and Stelck, 1975). Williams and Burk (1964) found 6 break 1n the marines sedlmentatlon in the f1anltoba area, suggesting Bland corlnectlon from the Dlstrlct of Keewatln through eastern M6fl1toba to the lake Sl~perlor reglon, lmplying that the only dlrect connection between the Interlor Sea with Baffln Bay, was yia the Arct1c. This hiatus was also documented by Meek and Hayden (1861) ln the United states between the Niobrara and Pierre Format1ons. Jeletzky (1971) suggested that the retreat of the sea towards the east was by a serles of strong pulses resultlng in the regression of the Campanlan and M66str1chtlan seas. During ttle Cretaceous1 the r1s1ng Corl1111era caused the western shoreline of the Interlor Sea to migrate eastwards and the Cordillera'l detritus produced deltaic cornplexes from the Mackenzie Valley to Ne\N Mexlcoo The foreland basin was continually subslding and thls down\",arplng aided in the eastward m1gration of the western shorel1ne. Thls also lndicates that trle water 'tIes becom1ng deeper in the central Plains sect10n of the Seaway (Fig. 2).
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1. Triarylamminium radical-cation complexes. The detailed study of manganese, copper and nickel metal-radical complexes with triarylamminium ligands was conducted. Stable, neutral and pseudo-octahedral coordination monometallic complexes with simple monodentate 2,2`-bipyridine ligand containing a redox-active N,N`-(4,4`-dimethoxydiphenyl-amino) substituent were synthesized and fully characterized. The one-electron oxidation process and formation of persistent radical-cation complexes was observed by cyclic voltammetry and spectroelectrochemical measurements. Evans method measurements were performed with radical-cation complexes generated by chemical one-electron oxidation with NOPF6 in acetonitrile. The experimental results indicate ferromagnetic coupling between metal and triarylamminium cation in manganese (II) complex and antiferromagnetic coupling in nickel (II) complex. This data is supported by DFT calculations which also lend weight to the spin polarization mechanism as an operative model for magnetic exchange coupling. Neutral bimetallic complexes with a new ditopic ligand were synthesized and fully characterized, including magnetic and electrochemical studies. Chemical oxidation of these precursor complexes did not generate radical-cations, but dicationic complexes, which was confirmed by UV-vis and EPR-experiments, as well as varied temperature magnetic measurements. DFT calculations for radical-cation complexes are included. A synthetic pathway for polytopic ligand with multiple redox-active triarylamine sites was developed. The structure of the ligand is presumably suitable for -spin polarization exchange model and allows for production of polymetallic complexes having high spin ground states. 2. Base-catalyzed hydrosilylation. A simple reductive base-catalyzed hydrosilation of aldehydes and ketones was adapted to the use of the cheap, safe, and non-toxic polymethylhydrosiloxane (PMHS) instead of the common PhSiH3 and (EtO)3SiH, which present significant cost and safety concerns, respectively. The conversion of silane into pentacoordinate silicate species upon addition of a base was studied in details for the cases of phenyl silane and PMHS and is believed to be essential for the hydrosilylation process. We discovered that nucleophiles (a base or fluoride-anion) induced the rearrangement of PMHS and TMDS into light silanes: MeSiH3 and Me2SiH2, respectively. The reductive properties of PMHS under basic conditions can be attributed to the formation of methyl silane and its conversion into a silicate species. A procedure for the generation of methyl silane and its use in further efficient reductions of aldehydes and ketones has been developed. The protocol was extended to the selective reduction of esters and tertiary amides into alcohols and aldimines into amines with good isolated yields and reduction of heterocyclic compounds was attempted.