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Electrochemical supercapacitors (ESs) are currently under development for electronics and automotive applications due to their hybrid properties inherited from batteries and capacitors. ESs exhibit higher power densities than batteries and energy densities than capacitors, and offer long cyclic life and rapid charge-discharge suitable for many applications. A promising candidate of electrode materials is manganese dioxide (MnO2), which has the advantages of high theoretical capacitance, low cost and environmentally friendly. However, the low electronic and ionic conductivities of MnO2 have limited its performance for practical applications. It has been demonstrated in literature that composite materials, which consist of conductive additives such as multi-walled carbon nanotubes (MWCNTs) and MnO2 can address this problem, however further investigations are required to produce ESs with superior performance for real-world applications. In this dissertation, novel colloidal fabrication techniques have been developed and advanced dispersants were employed to fabricate advanced nanocomposite electrodes. MnO2-MWCNTs composite electrode was fabricated with use of multifunctional dispersant. The multifunctional dispersant cetylpyridinium chloride (CPC) showed good dispersion of MWCNTs and capability of forming complex with the precursor of MnO2, which improved the homogeneity of the composite and generated unique morphology. The MnO2-MWCNTs composite electrode fabricated exhibited remarkable areal capacitance at high active mass loadings. New scalable fabrication technique was developed for MnO2-MWCNTs by using high solubility sodium permanganate (NaMnO4) precursor. The fabricated composite electrode showed superior performance compared to electrodes fabricated by other colloidal techniques at similar mass loading. Liquid-liquid extraction was employed to address the problem of particles agglomeration upon drying. Bio-inspired advanced extractor lauryl gallate (LG) was used for liquid-liquid extraction of particles. LG has organic catechol group allowed for strong adsorption on inorganic particles. Using LG as an advanced extractor has facilitated the transfer of particles from aqueous to organic phase to prevent agglomeration associated with drying procedure and improved mixing with MWCNTs. Advanced dispersants from bile acid salts and charged aromatic dyes families such as sodium taurodeoxychloate (TDS) and tolonium chloride (TL) were used as MWCNTs dispersants, to fabricate composite electrode with alternative metal oxides such as Mn3O4 and V2O3. Furthermore, 3,4-dihydroxybenzaldhyde (DHB) was investigated as a dispersing agent for Mn3O4 and used to fabricate Mn3O4-MWCNTs composite electrode with TL by Schiff base formation. Mn3O4 offers the advantages of small particle size compared to MnO2, and can be converted to MnO2 by electrochemical cycling to enhance capacitive performance. V2O3 was considered as an alternative to MnO2 due to its metallic conductivity at room temperature. An activation procedure has been developed, which promoted the formation of capacitive V2O5 surface layer on conductive V2O3 to increase capacitance. The advanced dispersants have shown excellent dispersion of MWCNTs in aqueous solutions at low concentrations and facilitated the formation of homogeneous composite with Mn3O4 and V2O3. Activation procedures were developed for the Mn3O4 and V2O3 composite electrodes, and the electrodes with high active mass loadings showed exceptional performance after activation. / Thesis / Doctor of Philosophy (PhD) / In modern society, the demand for clean and renewable energy have grown drastically and there is a need in development of advanced energy storage devices. Currently, the most common energy storage devices are batteries or conventional capacitors. Batteries can store a large amount of energy, however they are limited by their low power performance. Capacitors can charge and discharge rapidly, but the amount of energy stored is relatively low. Other than batteries and capacitor, electrochemical supercapacitors are emerging energy storage devices that offer the advantages of high power and energy density, fast charge-discharge and long lifetime. The objective of this work was to develop advanced nanocomposite electrode materials for electrochemical supercapacitor applications. New colloidal processing strategies have been developed and advanced dispersants were employed for the fabrication of high performance nanocomposites for electrochemical supercapacitor applications. The results presented in this work showed exceptional performances compared to literature data and paved a new way for further developments.

There is frequently a need for algorithms capable of automatic modification of geometric models in response to manufacturing process constraints. Designers typically initiate product models using ideal, exact geometry; however, several non-traditional manufacturing processes frequently require slight modifications to the ideal model to accommodate various manufacturing process constraints. These modifications can be difficult, complex, and tedious to compute. For instance, metal-ceramic brazing requires adjustments to the part geometry primarily to accommodate thermal expansion and to allow for the insertion of a narrow braze-filler gap. These adjustments depend on the particular geometry, material properties, and processing parameters. Any modification to these product model parameters necessitates extensive recomputation to reestablish a manufacturable part geometry. This thesis demonstrates in part the integration of geometry into the overall product model by having the non-geometric parts of the product model provide feedback to the geometry by means of automatically modifying its shape. The methodology is demonstrated in a prototype model which introduces the concept of auxiliary geometric structures. In particular, the auxiliary geometric structures provide a mapping between the designer's intent and the part geometry described in the solid model. The designer's intent is represented in a rule base for metal-ceramic brazing that is controlled by fuzzy logic. This rule base aids the user in quantifying and generating from the auxiliary geometric structures the geometric modifications needed to conform with a complex set of rules derived from both analytic and empirical work in metal-ceramic brazing / Master of Science

The problem addressed in this study was: What home modifications are made to residential environments to meet the functional capabilities of the aging in place audience? The study was conducted in two phases. In Phase I 102 Floyd County, Virginia, adults 65 years of age or older were interviewed in order to identify their task capabilities and identify the modifications being made to meet their environmental needs and task capabilities. Phase II consisted of a case study of six females taken from the Phase I sample group. This section of the study focused on the modifications identified in Phase I, the techniques used, and the reasons they were made. The findings indicate that 26% of the adults in the study were experiencing difficulty with at least one Activity of Daily Living, 33% were experiencing difficulty with at least one Instrumental Activity of Daily Living. However, like many older adults, these individuals had a relatively high function level and wanted to stay in their home as long as possible. Modifications are being made in order to equalize the participants' function level and the characteristics of the living environment. Housing education programs should be targeted toward the elderly and their family members and provide more information relating to aging in place. Professionals in housing and related fields should have the knowledge necessary to advise clients on making decisions to help insure their ability to live independently as they age. / Master of Science

Ce travail s’inscrit au sein du projet régional de recherche BEMA (Bois Eco Matériaux Aquitaine) qui allie partenaires universitaires et industriels afin de valoriser, à travers la filière panneaux de particules, des ressources abondantes en Aquitaine : le maïs et le Pin Maritime. L’objectif de cette thèse est de greffer de manière covalente des chaînes de polymère à la surface de fibres de bois afin de modifier leur état de surface et de favoriser leur comptabilisation avec un liant naturel et/ou synthétique. Pour atteindre cet objectif, nous avons choisi d’utiliser une technique de polymérisation particulière, la polymérisation radicalaire contrôlée. Le contexte scientifique international du début de la thèse montre la faisabilité du projet de par la réalisation de plusieurs études sur de la cellulose modèle de type papier filtre. Le défi de cette thèse consiste à transposer ce mécanisme sur des fibres de bois brutes afin de leur conférer de nouvelles propriétés (résistance à l’eau, caractère fongicide, meilleure comptabilisation…). Afin d’atteindre l’objectif énoncé ci-dessus, nous avons développé plusieurs aspects de la chimie des polymères en mettant en oeuvre différentes techniques de synthèse (RAFT, NMP) mais aussi de caractérisation adaptées à la présence de fibres de bois brutes (Mesure d’angle de contact, TGA, XPS). Enfin, nous avons valorisé la présence de polymères fonctionnels en insérant à la surface des fibres de bois des nanoparticules d’oxyde de silice ou de métaux de manière contrôlée. / This work is part of the regional research project BEMA (Bois Eco Matériaux Aquitaine) which combines academic and industrial partners to develop, through the wood pannel industry, abundant resources in Aquitaine: corn and Maritime Pine. The objective of this thesis is to covalently graft polymer chains on the surface of wood fibers in order to modify their surface properties and to facilitate their compatibilization with natural and/or synthetic binders. To achieve this goal, we chose to use a special polymerization technique, the controlled radical polymerization. The international scientific context of the beginning of the thesis shows the feasibility of the project through several studies carried out on model cellulose, such as filter paper. The challenge of this thesis is to implement this mechanism on raw wood fibers to give them new properties (water resistance, fungicidal character, best compatibilization ...). To achieve the objective stated above, we investigated several polymer synthetic pathways (RAFT, NMP) but also characterization techniques (Contact angle measurements, TGA, XPS) suitable with the presence of raw wood fibers. What’s more, we have valued the presence of functional polymers by inserting at the wood fibers surface oxide nanoparticles of silica or metal in a controlled manner.

Triazoles have been widely used as amide bond isosteres in chemical biology as linkers and to enhance proteolytic stability. The use of triazoles has grown exponentially since the discovery of the copper (I) catalysed alkyne azide cycloaddition reaction in 2002 as the reaction is solvent and functional group tolerant, and usually high yielding. The reaction is also orthogonal to reactions used in nature, meaning it has become a powerful coupling tool. In post-translational modification (PTM), proteins are modified by covalent attachment of functional groups to amino acid side chains. These PTM processes are generally thought to be dynamic and highly regulated by cell machinery, controlling protein function in response to stimuli. The ability to control function post protein synthesis allows organisms to have a smaller genome, which is advantageous as it reduces the energy required for DNA replication and repair. Research into the function of PTMs has been limited by the difficulty in generating recombinant proteins that bear a single PTM in a specific location. Although many elegant methods have been proposed that solve this problem, to date cysteine alkylation is one of the most successful techniques. For lysine PTMs, thia-lysine II (sLys) derivatives have been shown to be excellent mimics of lysine, where the only perturbation between the native lysine-containing analogue is the switch of a CH2 for S in the side chain. Biotin is a well-known PTM in biotin dependent carboxylases, where biotin is involved in CO2 transfer. Recently biotinylation has also been shown to be a PTM on many other proteins, however the role of biotinylation is not well understood. Biotin triazole III has been shown to be a good mimic of the biotin amide bond and retains excellent affinity to Avidin (Av). In Chapter 1 the effects of modification to the valeryl side chain, and orientation of the biotin triazole bond affect affinity to Av using ITC are investigated. Compounds III, V and VI are shown to have a KD < 120 pM, but further information on the binding affinity of these compounds could not be assessed by ITC. Biotin triazoles III-VI were also shown to be resistant to hydrolysis in serum, unlike the native biotin amide bond, which is hydrolysed by the enzyme biotinidase (BTD). Generation of amide sLys derivatives has been shown to be synthetically challenging. In Chapter 2, the synthesis and applications of chloromethyl-triazole biotin as a sulfhydryl selective alkylation reagent are investigated. The electron withdrawing nature of the triazole was proposed to give a ‘pseudo-benzylic’ halide α to the triazole, thus increasing reactivity. The controlled alkylation of peptides and proteins has shown that chloromethyl-triazole biotin shows enhanced reactivity over many commercial alkylation reagents and also gives good selectivity for cysteine. Alkylation of histone H4K12C gave the singly alkylated product, accompanied by low amounts of double alkylation. Biotinylation was confirmed by Western blot with anti-biotin. Due to the wide range of readily available functional azides, it was envisaged that halomethyltriazoles could be incorporated into other PTM mimics. In Chapter 3, efforts to expand the range of PTMs accessible using halomethyl-triazoles and further enhance the reactivity of chloromethyl triazoles by preparation of bromo- and iodomethyl triazoles are detailed. Synthesis of reagents to mimic malonylation, succinylation and GlcNAcylation PTMs is described and the reactivity of these halomethyl-triazole reagents is assessed. An alternate approach to the development of PTM mimics through cysteine propargylation and subsequent CuAAC coupling is also described in chapter 3. In conclusion, a series of new reagents have been developed to mimic protein PTMs through alkylation of cysteine. The reagents, which include biotin, GlcNAc, succinyl and malonyl mimics, are based on a halomethyl-triazole scaffold and have been successfully reacted with cysteine containing peptides and proteins.

Les modifications post-traductionnelles (MPTs) d’histones sont apparues comme un acteur majeur de la régulation de l’expression des gènes. Cependant peu de choses sont connues sur le réel impact des MPTs sur la chromatine. Il a été suggéré que les MPTs d’histones (H2A, H2B, H3 et H4) ont le potentiel de moduler la fonction chromatinienne selon un « codehistone » en recrutant des protéines spécifiques de liaison. L’objectif de mon projet est d’approfondir la fonction de l’acétylation du domaine globulaire de l’histone H3 et de comparer cette modification avec celles des queues N-terminale in vivo sur une lignée ES cellulaire. Pour étudier l’impact de ces MPTs in vivo, toutes les copies endogènes du gène H3 sauvage (WT) doivent être remplacées par des copies mutées. Ainsi la première étape de mon projet est d’établir une lignée cellulaire exprimant seulement H3 mutée (e.g reproduisant une acétylation permanente) afin d’étudier les effets des modifications sur le domaine globulaire de H3 sur (a) l’expression génique, (b) l’architecture chromatinienne mais également pour étudier (c) les effets réciproques et synergiques entre les différentes modifications du domaine globulaire et (d) comparer ces effets avec les modifications sur la queue N-terminale dans un système in vivo. / Post-translational modifications (PTMs) of histones have emerged as key players in the regulation of gene expression. However, little is known to what extent PTMs can directly impact chromatin. It has been suggested that PTMs of core histones (H2A, H2B, H3 and H4) have the potential to govern chromatin function according to the so called ‘‘histone code’’ hypothesis by recruiting specific binding proteins. The goal of my project is to gain insight in the function acetylation within the globular domain of H3 and to compare these modifications with histone tail modifications, in vivo by using the CRISPR in mouse embryonic stem cells (ES). To study the impact of PTMs in vivo, all endogenous wild type (WT) H3 gene copies have to be replaced with mutant copies. Hence, the primary focus of my project is to establish cell lines that exclusively express mutated H3 (e.g. mimicking acetylation) in order to study effects of H3 globular domain modifications on (a) gene expression (b) chromatin architecture as well as to study (c) cross talks and synergisms between globular domain modifications and (d) compare the effects with tail modifications in an vivo system.

Les cils sont des organites très conservés au cours de l’évolution des eucaryotes et présents à la surface de presque tous les types cellulaires. Ils sont constitués d’une structure microtubulaire, l’axonème, entourée d’une membrane en continuité avec la membrane plasmique. Ils sont nucléés par un corps basal, centriole ancré à la surface cellulaire. Grâce aux nombreux récepteurs qu’ils concentrent à leur membrane, tous les cils sont des senseurs de leur environnement. Ils peuvent aussi être motiles et assurer, par leur battement coordonné, le déplacement relatif de la cellule et du fluide environnant. Tandis que cil et structure centriolaire, hérités du premier eucaryote, ont été perdus par certains champignons et par les plantes supérieures, certains gènes codant des protéines ciliaires et centriolaires sont pourtant retrouvés dans le génome de ces espèces. Cette conservation de protéines sans l’organite suggère soit que ces protéines interviennent dans un même processus moléculaire utilisé dans plusieurs organites, soit qu’elles jouent des rôles dans des processus moléculaires distincts via leur interaction avec différents types de partenaires.J’ai choisi d’étudier l’une de ces protéines ciliaires et centriolaires, Bug22p, hautement conservée en séquence protéique entre l'homme et la paramécie, mais également présente chez les plantes supérieures. J’ai mené cette étude principalement sur la paramécie, système modèle pour la biogénèse des corps basaux et des cils, mais aussi sur des cellules de mammifère et de végétaux supérieurs. Si Bug22p est impliquée dans la détermination du battement ciliaire chez la paramécie, elle se localise également dans des cils immotiles de cellules de mammifère suggérant que son activité ciliaire n’est pas réduite à cette seule fonction. Des expériences d’inactivation génique suggèrent par ailleurs un lien entre l’activité de Bug22p et la polyglycylation. Sa surexpression dans les cellules de mammifère en culture entraîne l’apparition d’extensions cellulaires et une augmentation des réseaux de tubulines acétylées probablement associées à une stabilisation des microtubules. L'ensemble de mes résultats suggère donc un rôle de Bug22p dans la régulation de modifications post-traductionnelles. En plus d’être présente dans les structures ciliaires, Bug22p se localise aussi bien dans les noyaux de la paramécie que dans ceux des cellules humaines et des plantes supérieures Arabidopsis et Nicotiana. Ces observations ouvrent un nouveau champ d’études. En effet, si l’on sait que les tubulines ciliaires sont soumises à différentes modifications post-traductionnelles telles que polyglycylation ou acétylation, ce type de modifications touchent également des protéines nucléaires régulant ainsi le trafic de protéines nucléaires ou l’expression génique. Nous pouvons donc avancer l’hypothèse selon laquelle Bug22p agirait sur la régulation de ces modifications dans le cil et dans le noyau. Il serait donc intéressant de caractériser les modifications post-traductionnelles chez les plantes supérieures afin de vérifier une possible implication de Bug22p dans leur régulation et donc comprendre les raisons de sa conservation chez les végétaux. / Cilia, organelles that have been conserved throughout the evolution of eukaryotes, are found at the surface of most cell types. They are composed of a microtubular structure, the axoneme, surrounded by a membrane continuous to the plasma membrane. Cilia are nucleated by basal body, which is a centriole anchored to the cell surface. Cilia are environmental sensors concentrated in the ciliary membrane. Cilia can be motile and ensure the relative movement of the cell with respect to the surrounding fluid by their coordinated beating. While cilia and centriolar structures inherited from the first eukaryote have been lost by certain fungi and higher plants, certain genes encoding ciliary and centriolar proteins are found in the genomes of organisms lacking these structures. The conservation of these proteins without organelle suggests that these proteins are involved in the same molecular process into different organelles or proteins are involved into different processes through some interactions with different partners.I chose to study the ciliary and centriolar protein, Bug22p, highly conserved between human and Paramecium proteins sequences, and also present in higher plants. My work addressed this study primarily on Paramecium, a model system for biogenesis of basal bodies and cilia, and I also pursued investigation of mammalian cells and higher plants. I was able to show that Bug22p is necessary for efficient Paramecium ciliary beating, but I also localized in the immotile cilia of mammalian cells suggesting that Bug22p is not only restricted to the motile ciliary function. By knockdown experiments in Paramecium, I obtained evidence that Bug22p is involved in polyglycylation. Bug22p overexpression in mammalian cells led to the appearance of cell extensions and increased acetylated tubulin networks consistent with microtubule stabilization. My results suggest that Bug22p may regulate post-translational proteins modifications.Bug22p is also localized in the nuclei of Paramecium, human and higher plants such as Arabidopsis and Nicotiana. These observations open a new field of study. The axoneme microtubules are highly modified by post-translational modifications such as acetylation and polyglycylation; we know that in the nucleus, theses modifications are involved in the control of nuclear trafficking of some proteins and the regulation of gene expression. We can therefore speculate that Bug22p acts on the regulation of these changes in the cilium and in the nucleus. Finally, it would be interesting to characterize the post-translational modifications in higher plants to verify the possible involvement of Bug22p in their regulation and thus understand the meaning of its conservation in higher plants lacking cilia.

Shelf life of meat and meat products depends on the quality of meat and packaging stability. Meat color change, lipid oxidation, pH, and microbial contamination are the main causes that affect the nutritional, sensory, and physical characteristics by forming toxic compounds, off flavors, off odors, and undesirable color. The first objective of this study was to examine the effect of newly developed CO2 generating absorbent pads on beef, tuna and chicken meats. The second objective was to compare the effect of Type I (radical quenching) antioxidants eugenol and rosmarinic acid (RA) to that of Type II (metal chelating) antioxidants milk mineral (MM), phytate, and sodium tri-polyphosphate (STPP) in raw ground chicken patties. In the first study samples of beef semitendinosus muscle, boneless and skinless chicken breast, and yellowfin tuna loins were chosen and packaged with four different pad types. Red meats and chicken exhibited trends as would normally be expected during storage. Specifically, color became less appealing (beef and tuna color changed from red to brown, and chicken changed from yellow–pink to grey); pH increased, microbial counts increased, and lipid oxidation (rancidity) increased. Lightness (L*) values for chicken were within 46 – 54, for tuna L* value range was 21-26. Redness/greenness (a*) is an indicator of freshness in red meats, and for beef steaks an average value of 12.32 was noted on day 8, indicative of fresh red color. Recorded average lipid oxidation (TBA values in mg/kg of meat) for chicken (< 0.19 mg/kg) and tuna were low (< 0.16 mg/kg) and for beef (1.06 mg/kg). Even though there was a significant effect of storage time (P < 0.05) as expected, no significant (P >0.05) differences were observed between the four tested pad types over the 8-day testing period. In study 2, (Chapter 4) a significant antioxidant effect (P < 0.05) was observed in L* values of ground chicken color between treatments. Milk mineral effectively preserved fresh color and slowed lipid oxidation in chicken patties by day 10. Inverse correlations (P < 0.001) were observed between pH (increasing), and lightness, redness values (decreasing) from day 1 through 10. Increased pH levels from slightly acidic to basic or physiological pH resulted in high numbers for total aerobic plate-counts. There was a significant antioxidant effect on lipid oxidation values by day 10; eugenol and MM were more effective (P < 0.05) than STPP in controlling lipid oxidation measured as thiobarbituric acid reactive substances (0.198 mg/kg, 0.198 mg/kg, and 0.268 mg/kg, respectively). In conclusion, CO2 generating absorbent pads did not have a positive effect on meat quality, while the antioxidant milk mineral efficiently maintained color, and pH, and controlled lipid oxidation and limited the growth of aerobic bacteria when compared to other antioxidants.

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