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The maximum quantum yield (Fv/Fm), zooxanthellae density, chlorophyll a concentration and protein concentration of non-bleached and bleached colonies of the reef coral Acropora intermedia were measured in inlet of The Third Nuclear Power Plant of Nanwan Bay in southern Taiwan. A significant positive correlation was found between Fv/Fm and chlorophyll a concentration per zooxanthellae of non-bleached colonies. The chlorophyll a concentration per zooxanthellae and zooxanthellae density of non-bleached colonies were lowest in summer, and were significantly negative correlated with total radiant heat and seawater temperature, respectively. This suggests that the seasonal variation exist, and they maybe regulated by seasonal fluctuation of radiation and temperature. The Fv/Fm, chlorophyll a concentration per cm-2, chlorophyll a concentration per zooxanthellae, zooxanthellae density and protein were significantly lower than those of the non-bleached colonies in the bleaching events. However, compared to the non-bleached colonies, zooxanthellae density, chlorophyll a concentration per cm-2 and protein of bleached colonies were increased and significantly higher than those of non-bleached colonies, then decreased to similar level. However, Fv/Fm increased to similar level, but chlorophyll a concentration per zooxanthellae remained lower. It suggests that number of zooxanthellae rapidly increased while remained stable chlorophyll a concentration during recovery.

This thesis presents a collection of three short stories written or revised during my graduate tenure at Texas A&M University. Thus, what follows offers a solid example of the creative writing and literary knowledge obtained through creative writing coursework and support from English departmental faculty. In order to review my research methodology, I have provided an introduction to discuss each story?s development and literary influences. These stories, entitled ?Imagine a King,? ?Bleach Everything,? and ?Dotting the Iris,? explore themes of sacrifice, the incompatibility of happiness and truth, and the benefits and dangers of silence. However, the overarching theme revolves around the injurious treatment of things that should be considered sacred, namely self, family, and history.

The high speed transfer of information in materials with dimensions below the sub-diffraction limit is essential for future technological developments. Metallic nanoparticle (NP) waveguides serve a unique role in efficient energy transfer in this size regime. Light may be confined to metallic structures and propagate along the surface of the waveguide via propagating plasmon waves known as surface plasmon polaritons (SPPs). Plasmon propagation of energy in metallic structures is not perfect however and damping losses from the waveguide material lead to a characteristic exponential decay in the plasmon near field intensity. This decay length is known as the propagation length and serves as an excellent metric to compare various waveguide materials and structures to one another at particular excitation wavelengths. This thesis presents recent work in the development of a novel measurement technique termed bleach imaged plasmon propagation (BlIPP). BlIPP uses the photobleaching property of fluorophores and far field fluorescence microscopy to probe the near-field intensity of propagating plasmons and determine the propagation length. The experimental setup, image analysis, conditions, and application of BlIPP are developed within this thesis and an in depth review of the 1-photon photobleaching mechanism is also investigated. The BlIPP method is used to investigate long plasmon propagation lengths along straight chains of tightly packed Au NPs through the coupling of light to sub-radiant propagating modes, where radiative energy losses are suppressed. The findings of this work reveal, experimentally, the importance of small gap distances for the propagation of energy. Complex chain architectures are then explored using BlIPP measurements of tightly packed straight and bent chains of spherical silver NPs. We observe the highly efficient propagation of energy around sharp corners with no additional bending losses. The findings of this thesis demonstrate the advantages and capabilities of using BlIPP propagation length measurement. Further, BlIPP is used to reveal the advantage of coupling light to sub-radiant modes of NP chains, which demonstrate the ability to guide light efficiently across long distances and around complex structures, bringing us a step closer to the goal of applying plasmonic devices and circuitry in ultra compact opto-electronic devices.

Indiana University-Purdue University Indianapolis (IUPUI) / This study evaluated the color stability of bleach shade composites when activated by a high-intensity quartz tungsten-halogen (QTH) light source after 1 day, 7 days, and 30 days of exposure to different conditions. The color stability of bleach shade composites depends on various factors, namely, the resin material, the shade of the resin material, the storage method, and the storage time.

<p>N-chloramide containing and primary amine-containing microgels were prepared by post-modification of thermosensitive microgels in alkaline bleach. The objective of this project was to develop simple strategies for preparation of functionalized microgels.</p> <p>N-chlorination of linear poly(N-isopropylacrylamide) (PNIPAM) in bleach at high pH resulted in a novel N-chloramide containing copolymer: poly(NIPAM-co-NIPAMCl). The chlorinated PNIPAM showed controlled phase transition temperature and oxidative ability. The N-chlorination of linear PNIPAM inspired the preparation of N-chloramide containing PNIPAM microgels in a similar way. The phase transition temperature of the resulted chlorinated microgels, which corresponds to the extent of N-chlorination, was affected by the reaction temperature and salt concentration. The reaction between the chlorinated microgels and glutathione is proposed as diffusion controlled.</p> <p>The N-chlorination of poly(N-isopropylmethacrylamide) (PNIPMAM) microgels in bleach was restricted, in comparison with PNIPAM microgels. The active chlorine content of chlorinated PNIPMAM microgels was about one-tenth of that of chlorinated PNIPAM microgels under the same N-chlorination condition. It is proposed that the high stability of PNIPMAM in bleach is a result of the electron-donating effect of methyl groups on PNIPMAM backbone. Hence, core-shell microgels with PNIPAM cores and poly(NIPAM-co-NIPMAM) shells showed improved colloidal stability after N-chlorination because the shell was less chlorinated and served as a steric stabilizer.</p> <p>Finally, primary amine-containing microgels were prepared via Hofmann rearrangement of copolymers of methacrylamide, which decomposed to give amines, and NIPMAM, which did not react. The method was further extended to give amphoteric microgels by including acrylic acid in the starting microgels. Although other approaches to aminated and amphoteric microgels have been developed, this approach is particularly attractive because of the ease of the reaction and the ability to control the microgel isoelectric points.</p> / Doctor of Philosophy (PhD)

In this study I examine the two major cosmetic categories - products for skin and products for hair - aimed at frican American women and advertised within the black press between 1920 and 1960. Specifically, I examine the Chicago Defender, Afro-American, Plaindealer, and Ebony. My project analyzes the images and conceptions of blackness and beauty sold to women of colour by white-owned and black-owned cosmetics companies.  I explore the larger racial and social hierarchies these advertising images and messages maintained or destabilized. A central theme of this project has been tracing the differences in advertising messages and conceptions of beauty communicated by black-owned and white-owned companies. Many of the images and much of the advertising copy produced by black-owned cosmetic companies challenged hegemonic beauty ideals that venerated white beauty and sold white idealization as a norm. The black cosmetic industry, however, was dominated by white-owned companies. The dominant position of white-owned companies was linked to the advantages associated with whiteness, which allowed these companies to advertise with greater frequency throughout the forty-year period. White-owned and black-owned companies often pursued diverging advertising strategies and messaging about black beauty. An important finding of the project is that white-owned companies were more likely to use degrading language and stereotypes to describe black beauty in their advertisements. However, a company’s racial identity did not always determine advertising strategies or messaging about black beauty. An important concept that permeated the 1920s and 1930s was the strategy of racial uplift, which was promoted by several black-owned companies. This strategy tapered out by the1940s as new technologies like photography regularly depicted black women with dignity and accuracy. The 1940s and 1950s witnessed new advertising strategies including the appeal to glamour. This period also saw the introduction of Ebony magazine, which fundamentally altered advertising messages through their appeal to middle class sensibilities. / Thesis / Master of Arts (MA) / My project analyzes skin bleaching and hair straightening advertisements appearing in four black-owned periodicals between 1920-1960: Chicago Defender, Afro-American, Plaindealer, and Ebony. The main goal has been to document the advertising messages about blackness and beauty communicated to black women through the advertisements of black-owned and white-owned cosmetic companies. I explore the larger racial and social hierarchies these advertising images and messages maintained or destabilized. A major finding of this project has been that advertising messages usually, but not always, diverged along racial lines. White-owned companies were more likely to use denigrating language to describe black hair and skin, and more likely to measure the beauty of black women based on how closely they approximated whiteness. Black-owned companies tended to challenge this ideology. They used messages about racial uplift as part of this challenge.

The research presented has been focused on understanding the surface effects on the optical and electronic properties of some metallic and semiconductor nanomaterials. When the particle sizes are on the nanometer length scale, a large fraction of atoms in the particles are on the surface. The bonding of the surface atoms being unsaturated could cause trapping and introduce defects that interact with the excited electrons. The effect of the surface on the optical and electronic properties of some semiconductor and metallic nanoparticles is investigated. When the size and shape of nanomaterials change, both the electron density of the excited electrons on the surface and the electronic structure change. Therefore, it becomes important to understand how these changes affect the electronic motion in the particles in order to exploit their full potential in a variety of applications. Semiconductor nanoparticles studied include cadmium selenide (CdSe) and cadmium sulfide (CdS). Effect of changing CdSe shape and size on optical and electronic properties has been investigated and the ability for the CdS nanoparticles to show optical gain (stimulated emission) in solution at room temperature is reported. Effect of surface phonon contribution on the exited electron relaxation in copper nanoparticles is investigated. For the particles size smaller than the mean free path of the electrons in the metal, electron-surface phonon coupling becomes an important factor (contribution) for hot electron relaxation. In the thesis presented, it is shown for the first time the size depended electronic relaxation in copper nanoparticles. Fluorescence due to surface plasmon field enhancement is observed for copper nanoparticles to be million times stronger than the fluorescence observed from bulk copper.

Ce travail est consacré à l’étude de l’impact des lavages chimiques à l’hypochlorite de sodium (NaOCl) effectués sur des membranes polymères polyéthersulfone (PES)/polyvinylpyrolidonne (PVP) (95%/5%) utilisées pour la filtration de l’eau ou du lait. Sur les sites d’exploitation les lavages chimiques sont nécessaires pour maintenir les propriétés de filtration des membranes qui se colmatent au cours de leur utilisation. L’objectif de cette étude est de déterminer les mécanismes de dégradation de ces deux polymères au contact de l’agent nettoyant, puis de corréler ces évolutions aux changements de propriétés macroscopiques des membranes en réalisant une analyse multi-échelle. Dans un premier temps, l’étude de l’impact de NaOCl sur des polymères modèles, le PES d’une part et la PVP d’autre part, a montré que la PVP s’oxyde lorsqu’elle est dissoute dans NaOCl ce qui n’est pas le cas de films de PES. A partir de l’identification des produits d’oxydation, un mécanisme d’oxydation radicalaire de la PVP mettant en jeu les radicaux hydroxyles provenant de la solution de NaOCl a été proposé. Dans un deuxième temps, afin de s’affranchir de l’hétérogénéité des membranes PES/PVP, des films de mélanges modèles PES/PVP à différents pourcentages de PVP ont été préparés. Leur immersion dans une solution de NaOCl provoque non seulement l’oxydation de la PVP mais aussi celle du PES montrant sans ambiguïté l’effet pro-dégradant de la PVP sur le PES. Dans un troisième temps, il a été montré que le vieillissement des membranes PES/PVP peut être explicité à partir des résultats obtenus sur les mélanges modèles, et que l’évolution de la structure chimique de la PVP pouvait être corrélée avec la perte des propriétés mécaniques des membranes permettant de faire le lien entre l’évolution de la structure chimique et la perte des propriétés macroscopiques. Il apparait donc au final que l’additif ajouté au PES pour rendre les membranes hydrophiles est le talon d’Achille de la structure. Le suivi de l’oxydation de la PVP contenue dans les membranes exposées à NaOCl a été proposé pour servir de marqueur moléculaire de vieillissement. / This work was devoted to the study of the impact that chemical cleaning with sodium hypochlorite (NaOCl) has on polyethersulfone (PES)/polyvinylpyrrolidone (PVP) (95%/5%) membranes, commonly used for water and milk filtration processes. In onsite plants, chemical cleanings are widely used to maintain membranes filtration properties. The aim of this thesis is to determine the degradation mechanisms of these two polymers in contact with NaOCl and to correlate this information with the evolution of the macroscopic properties of the membrane through a multi scale analysis. Firstly, the study of NaOCl impact on both PVP and PES, treated separately as “model polymers”, showed us that dissolved PVP is oxidised, whereas PES film remains stable. Thanks to the identification of PVP oxidation products, a radical degradation mechanism by means of hydroxyl radicals from NaOCl solution has been proposed. Secondly, in order to overcome membrane heterogeneities, several films with different PES/PVP ratios were prepared by varying the amount of PVP. The immersion of these films in NaOCl solutions provoked the oxidation of both PVP and PES, allowing us to clearly identify the degrading effect that PVP has in PES oxidation. Thirdly, the evolution of PVP chemical structure was correlated with the loss of the membrane mechanical properties, demonstrating that PVP, used as an additive (5%), is the weak point of PES/PVP membranes. The monitoring of PVP oxidation in membranes in contact with NaOCl was proposed as a molecular marker of ageing.

Made available in DSpace on 2015-03-26T13:53:12Z (GMT). No. of bitstreams: 1 texto completo.pdf: 727392 bytes, checksum: 517cdc64095df68fed6389220058244a (MD5) Previous issue date: 2005-07-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The nutrition of ornamental plants plays an important role in the production of quality seedlings and flowers. In general, studies focusing on nutrition of such plants are rare, particularly for orchids, which represent a wide field for new research. On this background, our study investigated mainly: the performance of in vitro-grown orchid plants in different chemical media compositions; the effect of the addition of organic and/or chemical fertilizers; and lime addition to the growth medium. In vitro cultivation was evaluated regarding the plant response to different mineral doses and compositions in the medium. The Knudson C medium and that of Novais or NPK fertilizers were used as nutrient sources for this purpose. Two studies were realized in the experiments in pots: one tested different organic fertilizers (a commercial and another homemade one, the latter composed of castor bean meal, bonemeal and ashes) or mineral fertilizers (Peter s or Ca nitrate), applied individually or jointly. The second tested the application of lime doses to the growth medium of plants of the genus Epidendrum. Results obtained in vitro showed that the simple use of NPK fertilizers in culture medium for orchids is feasible; maximal seedling growth was achieved with doses of 5 g L -1 . The simultaneous application of homemade organic and Peter s fertilizers led to a significant increase in plant growth, while separate applications of the two fertilizers did not result in significant differences between them. The commercial organic fertilizer provoked B toxicity symptoms in the plants, as demonstrated in the tissue analysis. Lime application resulted in a higher total dry matter yield and number of leaves per plant. There was however no significant difference in plant height, resulting in plants with shorter internodes, which indicates a probable Zn deficiency. / A nutrição de plantas ornamentais é um importante fator para a obtenção de mudas e flores de qualidade. De modo geral, estudos de nutrição para essas plantas são escassos, em particular para as orquídeas, que apresentam um amplo campo para novas pesquisas. Sendo assim, os principais objetivos deste trabalho foram: estudar o comportamento de plantas de orquídeas cultivadas in vitro, submetidas a diferentes composições químicas de meios; estudar o efeito da adição de fertilizantes orgânicos e, ou, químicos e a de calcário no substrato de cultivo. Para os cultivos in vitro, foram realizados estudos com o objetivo de avaliar as respostas das plantas a diferentes doses e composições minerais no meio, sendo, para isso, utilizados os meios Knudson C e de Novais, ou fertilizantes NPK como fontes de nutrientes. Em experimentos em vasos, foram realizados dois estudos: um testando diferentes fertilizantes orgânicos (um comercial e outro doméstico, sendo o último composto por torta de mamona, farinha de ossos e cinzas), ou, minerais (Peters® ou nitrato de Ca), aplicados individualmente ou em conjunto, e um outro testando de doses de calcário no substrato de cultivo de plantas do gênero Epidendrum. Os resultados obtidos in vitro mostraram ser viável a simples utilização de fertilizantes NPK no meio de cultivo para orquídeas, sendo o crescimento máximo das mudas obtido com a dose de 5 g L-1. A aplicação simultânea dos fertilizantes orgânico doméstico e Peters® levou a um significativo aumento no crescimento das plantas, sendo que a aplicação isolada destes dois fertilizantes não resultou em diferenças significativas entre eles. O fertilizante orgânico comercial proporcionou sintomas de toxicidade por B nas plantas, comprovados pela análise de tecidos. A aplicação de calcário resultou em incremento na produção de matéria seca total e no número de folhas de plantas, entretanto, sem diferenças significativas em termos de altura de plantas, o que resultou em plantas com entre-nós mais curtos, indicando uma provável deficiência de Zn.