Th. doct.-ing.--Génie électrique--Toulouse--I.N.P., 1984. N°: 355.

‘Lord Baltimore’ hardy hibiscus (Hibiscus moscheutos L.) was used in the mass encapsulation protocol, rinsing effects on bulk encapsulation, growth comparisons using K-NAA, acclimatization to greenhouse environment, and leaf anatomy comparisons. Nodal segments, each containing a single axillary bud, were harvested and cut to 4mm prior to mass encapsulation. Results showed that using 2.75% alginate with a concentration of 60 or 80 mM calcium chloride produced an alginate mass, or “cookie”, which was able to hold together during rinsing protocols. The rinsing study resulted with the potential to reduce rinse times from 2 three-minute rinses to 1 one-minute rinse. After 4 weeks under mist, ~58% of root growth was generated when using 1 one-minute rinse. After 8 weeks under mist, the greatest percentage of shoot and root growth occurred when using 1 one-minute rinse. The use of K-NAA in the gel matrix, after four weeks, resulted in no discernable differences. Concentrations of 0 or 0.1 µM will generate a greater percentage of shoot and root growth. Using 1.0 µM K-NAA, and extending the time under mist to 8 weeks, will result in a greater percentage of shoots and roots generated. Acclimatization study investigated the survival rates on mass encapsulated nodal segments, looking at different media, depth of planting and humidity. Increases in shoot lengths can be expected up to 8 weeks under mist and planted either on top or 1 cm deep. A reduction in root growth was seen when placed on top of the medium after 4 weeks. The anatomical study found differences in the leaf cell lengths based on the stage of leaf development. However, there was no indication of a gradual change in anatomy as they adapted from in vitro to greenhouse environment. The best results were found when comparing epidermal, palisade and spongy mesophyll cells on the fourth fully expanded leaf under mist. Hydrangea quercifolia ‘Snow Queen’ was used to test the effects of tissue culture media and plant growth regulators. Research found that using dichloroisocyanuric acid (NaDCC) resulted in a decrease of contamination on explants without a reduction in the number of shoots produced. This would reduce the amount of time and labor on the encapsulation procedure, as no rinsing is required. The best result, looking a nutrient formulation, was found to be WPM with 1 µM BA added.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Esta dissertaÃÃo tem como escopo a anÃlise das funÃÃes discursivas das anÃforas encapsuladoras e se restringe Ãs que se realizam por meio de sintagmas nominais (tambÃm chamadas de rÃtulos). Adotamos a perspectiva teÃrica de que o fenÃmeno pesquisado situase na atividade discursiva de referenciaÃÃo, concebida como uma (re)construÃÃo do real, advinda da interaÃÃo entre os falantes, de forma intersubjetiva. Propomos uma classificaÃÃo das possÃveis funÃÃes assumidas pelas anÃforas encapsuladoras em diferentes contextos discursivos. Para tal fim, abordamos, inicialmente, a proposta classificatÃria de Cavalcante (2003) dos processos referenciais, entre os quais estÃo inseridas as anÃforas encapsuladoras. Partindo dessa classificaÃÃo, retomamos os pressupostos de Francis (1986;1994) acerca da rotulaÃÃo e discutimos os trabalhos de Carvalho (2005) e Koch (2006), que tambÃm se baseiam nos estudos da autora. Tomamos como base classificatÃria a sugestÃo de Koch (2004) sobre as funÃÃes cognitivo-discursivas das expressÃes nominais referenciais, e propusemos uma reorganizaÃÃo dos critÃrios que envolvem tais funÃÃes. Nosso corpus consta de 70 textos de gÃneros variados: destes, 50 textos pertencem ao banco de dados do grupo de estudos Protexto/UFC, e os demais foram selecionados considerando apenas a ocorrÃncia do recurso coesivo estudado. Com a anÃlise dos dados, verificamos traÃos funcionais das anÃforas encapsuladoras que vieram a compor nossa classificaÃÃo e nos levaram a constatar que estas anÃforas podem ser multifuncionais, atendendo aos propÃsitos discursivos de seus interlocutores. / This dissertation has as a goal the analysis of discoursive functions from anaphoric encapsulation. This work restricts on the analysis of these anaphoras achieved by composed nuclei from nominal group sometimes called rotulation. We adopted the theoretical perspective that the researched phenomenon is situated in the referencing discoursive activity, conceived as a (re)construction of the reality, came from, the interaction between the speakers, in an intersubjective way. We propose a classification of the possible functions took on by anaphoric encapsulation in different discoursive contexts. For such end, we approached, initially, the classifying proposal by Cavalcante (2003) about referential expressions, in which are inserted the anaphoric encapsulation. From this classification, we adopted the perspective by Francis (1986; 1994) about rotulation, denominated in this work as anaphoric encapsulation; we still discuss the works of Carvalho (2005) and Koch (2006) that are based on the studies of the author. It bears emphasis that based on the suggestion of Koch (2004) about the cognitive-discoursive functions from the lexical referential expressions, which were the parameter for our proposal of functions of anaphoric encapsulation and organization of criteria that involved these functions. Our corpus has 70 varied-genre texts: from these, 50 texts belong to the database of Study Group Protexto/UFC; the others were selected, considering just the occurrence of the cohesive resources studied. With the analysis of these samples, we checked functional traits of anaphoric encapsulation may be multifunctional, according to discoursive proposals of their interlocutors.

Despite the great success of hip implant surgeries, wear particle-induced implant aseptic loosening still limits the implant longevity. Simvastatin, an FDA-approved cholesterol lowering statin, is a promising drug candidate for the treatment of implant aseptic loosening due to its anti-inflammatory properties as well as its ability to stimulate bone growth and inhibit bone resorption. In addition, alginate microspheres have been used extensively in drug delivery applications because of alginate properties, including biocompatibility and gelation in mild conditions. However, the hydrophobicity of simvastatin, as well as the large alginate microsphere pore size leading to the leakage of low molecular weight drugs are limiting factors for their use as a delivery system for simvastatin. Therefore, the objectives of this thesis were twofold: 1. To complex simvastatin with 2-hydroxypropyl-β-cyclodextrin (HP-βCD) in order to increase its solubility; and 2. To increase simvastatin encapsulation efficiency in alginate microspheres by coating the microspheres with chitosan, adding dextran sulfate in the alginate solution, and optimizing the gelation conditions used for the synthesis of the microspheres (e.g., volume of gelation medium, curing time, and addition of simvastatin in the gelation medium). Results showed that simvastatin complexation with HP-βCD increased with HP-βCD to simvastatin molar ratio, to a maximum of 97.6% at the molar ratio of 10. Results also showed that chitosan coating of the alginate microspheres increased simvastatin encapsulation efficiency (up to 10.6%), which was further improved (up to 14.0%) when adding 2.0% (w/v) dextran sulfate to the alginate solution. This increase was likely due to electrostatic interactions between dextran sulfate and chitosan in addition to alginate, resulting in a denser coating. Finally, the addition of simvastatin in the gelation medium was shown to also increase simvastatin encapsulation (up to 22.4%), likely because of a decrease in the diffusion of simvastatin out of the microspheres. Overall, this work completed the initial steps for the development of an alginate-based drug delivery system for simvastatin with the long-term goal of providing a local delivery of simvastatin to modulate implant aseptic loosening.

Despite advances in treatment, heart failure remains one of the top killers in Canada. This recognition motivates a new research focus to harness the fundamental repair properties of the human heart, with human cardiac stem cells (CSCs) emerging as a promising cell candidate to regenerate damaged myocardium. The rationale of this approach is simple with ex vivo amplification of CSCs from clinical grade biopsies, followed by delivery to areas of injury, where they engraft and regenerate the heart. Currently, outcomes are limited by modest engraftment and poor long-term survival of the injected CSCs due to on-going cell loss during transplantation. As such, we explored the effect of cell encapsulation to increase CSC engraftment and survival after myocardial injection. Transcript and protein profiling of human atrial appendage sourced CSCs revealed strong expression the pro-survival integrin dimers αVβ3 and α5β1- thus rationalizing the integration of fibronectin and fibrinogen into a supportive intra-capsular matrix. Encapsulation maintained CSC viability and expression of pro-survival transcripts when compared to standard suspended CSCs. Media conditioned by encapsulated CSCs demonstrated superior production of pro-angiogenic/ cardioprotective cytokines, angiogenesis and recruitment of circulating angiogenic cells. Intra-myocardial injection of encapsulated CSCs after experimental myocardial infarction favorably affected long-term retention of CSCs, reduced scar burden and improved overall cardiac function. Taken together, cell encapsulation of CSCs prevents detachment induced cell death while boosting the mechanical retention of CSCs to enhance repair of damaged myocardium.

The Thai automotive industry was the third largest industry in the country and contributed nearly 12% of Thai GDP in 2010. Thailand is projected to be in the world’s top ten vehicle production countries by 2015. In 2011, the country produced 1.8 million vehicles and 600,000 units were for domestic consumption. The luxury car industry in Thailand represents roughly 5% of the total automotive market in 2011. Luxury car consumption in Thailand reached its peak in 1995 with the domestic consumption of 23,265 units. In 1997, Thailand triggered the world economic meltdown by devaluing the Thai currency. Consequently, luxury car sale volume then dropped to 3,383 units in 1998. Since then Thailand’s automotive industry has gone through a series of changes through political unrest (military coup – 2007, red shirt protest - 2010), global economy (US sub-prime crisis - 2008), and natural disaster (Japan’s tsunami – 2011, Thailand’s mega flood – 2011). For the past decade, luxury car sales volume has stagnated at around 10,000 units, despite Thailand’s GDP averaging growth of 7%. The study of the Thai luxury car industry provides a unique opportunity to probe the industry led by international firms entering fierce competition to win local consumers. This study looks through consumers’ buying criteria and reasons why Thai consumers purchase highly priced luxury cars. The study explores the roles of innovations in the Thai luxury car industry. When services are packaged with core products, this package attempt is classified as ‘service encapsulation’. The study explores the role of service encapsulation in Thailand and the key players who deliver values of service encapsulation. A mixed research methodology approach was used, starting with 30 face-to-face interviews with executives who run Thai luxury car companies and other key stakeholders. Findings and outcomes are used to design the questionnaire of ‘Service Encapsulation in Thailand Luxury Car Industry’. The survey includes 206 survey participants. Outcomes from the qualitative and quantitative parts are integrated with the literature on innovation and service innovation to come up with a Service Encapsulation Commercialization Framework. The framework aims to provide insight on the interplay among four key elements: internal parties, external parties, social factors and service encapsulation enablers, based on the original work of Sundbo and Gallouj (2000). The study provides insights on how organizations can maximize returns on innovation through service encapsulation, by using the Thai luxury car market as a case study.

No description available.

The presented diploma thesis focuses on the use of plant growth promoting bacteria as an ecological alternative to conventional fertilizers. The incorporation of bacterial cells into hydrogel carriers is already a well-studied topic, but due to its disadvantages it has not yet found wider application in agriculture. This work offers a novel concept of encapsulating bacteria by gelation directly from the culture. This is achieved by crosslinking the bacterial alginate produced by the model microorganism Azotobacter vinelandii. Since this process was not described before, first its optimization was needed. Alginate production was determined gravimetrically, and its parameters were further characterized using available analytical methods – infrared spectroscopy to monitor structural parameters (monomer composition and the extent of acetylation), dynamic light scattering to characterize the size distribution and AF4-MALS-dRI to obtain the molecular weight. Bacterial PHB production was also investigated using gas chromatography and infrared spectroscopy. The second part of the work is focused on the optimization of the gelling process using bacterial alginate from the culture and CaCl2 as a crosslinking agent. Rheological experiments were used as a tool in understanding the viscoelastic properties of the prepared gels. Gelation was demonstrated within the first day after inoculation. Maximum production of alginate (1,9 ± 0,3) g/l was reached on the fourth day after inoculation. It was found that the addition of 5 g/l of calcium carbonate promotes the production of alginate. Nevertheless, further addition of CaCO3 (30 g/l) showed adverse effects on the molecular weight and is therefore not recommended. Production of PHB was confirmed by both FTIR and GC measurements, with a maximum yield of (23 ± 3) % CDW. Rheological testing confirmed that the product of the crosslinking was a gel. It was found that the crosslinker concentration plays an important role at time 0 min of the gelation, forming a denser network in the structure and causing higher rigidity. Using the highest studied concentration of CaCl2, the critical strain reached values of (5,0 ± 0,7) %. Finally, the incorporation of bacterial cells into the hydrogel was confirmed using fluorescence microscope.

Microencapsulation of stem cells in hydrogel for use in therapeutic applications has been shown to improve cell retention at the site of injuries due to their mechanical and immunoprotective properties. These microscale droplets (cocoons) can be produced at high throughputs within microfluidic channels. Currently, the ability for cells to egress hydrogel cocoons is under investigation. This egress can correlate with therapeutic efficacy, and so promoting or inhibiting the egress of cells can be a vital component of viable treatments. Previously, a second hydrogel layer was shown to reduce egress, but issues involving cell proliferation were unchanged. We propose a microfluidic process to encapsulate cells in two layers of thermoresponsive hydrogels, in which the inner core melts at physiological temperatures to form hollow cocoons that allow cells free motion inside the immunoprotective shell. We hypothesize that the open volume would increase cell viability and proliferation, without increasing cell egress due to the uninterrupted hydrogel shell. In this project the encapsulation of NIH 3T3 cells in hollow agarose cocoons was achieved. 3T3 cells were first encapsulated in thermoreversible gelatin which were then re-encapsulated in agarose through the use of a flow-focusing microfluidic channel with on-chip mixing of two inlet flows to produce hollow cocoons. The production of these cocoons showed the potential of high throughput, monodisperse samples with future investment. Preliminary investigation in the behavior of the encapsulated cells showed that the cells maintain high viability over the course of 48 hours. There are early indications that the hollow nature of correctly formed cocoons can limit cell egress, and may allow for proliferation in the cocoon.

Zeolite-supported transition metal catalysts, which couple the unique size- and shape-selectivity arising from the well-defined microporous structure of zeolites with the inherent high activity of metal species, have demonstrated remarkable performance in numerous catalytic reactions. Conventionally, such catalysts are prepared by loading metal species in the micropores of zeolites in the form of clusters (each containing only several atoms). Despite their high catalytic activity, the ultra-small clusters are usually highly mobile, and tend to migrate from the micropores to the crystal surfaces of zeolite during the reaction, where they agglomerate and deactivate. In this dissertation, we attempted to solve this issue by encapsulating metal nanoparticles (NPs) in zeolite crystals, based on the following considerations: (i) compared to clusters, nanoparticles have similar catalytic activity but much less mobility; and (ii) as long as the active sites are inside the zeolite crystals (not necessarily in the micropores that are too small to accommodate nanoparticles), they can exhibit selectivity associated with the zeolite structure. In the first chapter, we gave a general introduction to zeolites and zeolite supported catalysts, focusing on the preparation of hierarchical zeolites that are the main catalyst support materials used in the research projects of this dissertation. In the second chapter, we encapsulated highly dispersed Pd NPs (~2.6 nm) in zeolite ZSM-5 crystals, and used the obtained catalyst (Pd@SG-ZSM-5) for the hydrogenation of cinnamaldehyde. The confinement effect gave rise to an interesting catalytic behavior: compared with the traditional supported Pd catalyst prepared by impregnation, Pd@SG-ZSM-5 showed a 2.5-fold enhancement in the selectivity of hydrocinnamaldehyde (73% vs. 30%). Liquid adsorption combined with infrared spectroscopy characterization revealed that Pd@SG-ZSM-5 catalyst adsorbs much less reactant and product molecules than traditional catalyst, thereby suppressing the formation of by-products and leading to high selectivity. In chapter three, we developed a new method to encapsulate in situ produced molybdenum carbide (MoCx) in zeolite ZSM-5 for the methane dehydroaromatization (MDA) reaction. In this method, the structure-directing agent used to synthesize hierarchical zeolite ZSM-5 was utilized to reduce molybdenum precursor through a calcination process in an inert atmosphere. The zeolite subsequently underwent a secondary growth process to achieve encapsulation. The catalytic behavior of the as prepared catalyst in MDA consolidate our previous conclusion that MoCx particles outside the microporous channels can also act as the active sites for MDA, whereas it is traditionally viewed that only MoCx clusters inside the micropores are active sites. In addition, the encapsulation strategy allowed us to design experiments to answer one open question related to MDA, namely whether the Brønsted acid (BA) sites of the zeolite play a catalytic role in the conversion of methane to aromatics or only promote the dispersion of the Mo species. We encapsulated MoCx particles, which had proven to be active sites, in pure siliceous zeolite (Silicalite-1) that does not contain BA sites. The catalyst did not exhibit MDA activity even when aromatic compounds were introduced into the system by pre-adsorption or co-feeding, indicating that the BA sites are responsible for the oligomerization/cyclization step during MDA. Finally, in chapter five, we summarized the dissertation and gave our perspectives and outlooks on the further development of encapsulated catalysts based on zeolites.