Texte remanié de: Diss.--Kassel, 1995. / Bibliogr. p. 309-330. Notes bibliogr.

Dissertation--Mainz--Johannes-Gutenberg-Universität, 2006. / Contient le texte en danois de Hans Christian Andersen, ainsi que sa traduction allemande : "Den standhaftige Tinsoldat = Der standhafte Zinnsoldat" Bibliogr. p. 202-209.

Texte remanié de: Ph.D.--Dunedin--University of Otago, 1992. / Bibliogr. p. 340-377. Index.

Thèse de doctorat : ETUDES GERMANIQUES : Metz : 1995. / 1995METZ008L. 100 ref.

Zugl.: Trier, Univ., Diss., 2004

Tendons, essential tissues that connect muscles to bones, are susceptible to rupture/degeneration due to their continuous use for enabling movement. Often surgical intervention is required to repair the tendon; relieving the pain and fixing the limited mobility that occurs from the damage. Unfortunately, post-surgery immobilization techniques required to restore tendon properties frequently lead to scar formation and reduced tendon range of motion. Our ultimate goal is to create an optimal tendon prosthetic that can stabilize the damaged muscle-bone connection and then be remodeled by resident cells from the surrounding tissues over time to ensure long-term function. To achieve this, we must first understand how cells respond to and interact with candidate replacement materials. The most abundant extracellular matrix (ECM) protein found in the body, collagen, is chosen as the replacement material because it makes up the majority of tendon dry mass and it can be remodeled by cell-based homeostatic processes. Previous studies found that Di-catechol nordihydroguaiaretic acid (NDGA) cross-linked fibers have greater mechanical strength than native tendons; and for this reason this biomaterial could be used for tendon replacement. This work focuses on investigating the behavior of fibroblasts on NDGA cross-linked and uncross-linked collagen samples to determine if cross-linking disrupts the cell binding sites affecting cell spreading, attachment, and migration. The in-vitro platform was designed by plasma treating 25 mm diameter cover slips that were exposed to 3-aminopropyl-trimetoxysilane/toluene and glutaraldehyde/ethanol solutions. The collagen solution was then dispensed onto the glutaraldehyde-coated cover slip and incubated for fibrillar collagen matrix formation. The collagen matrices were submerged in NDGA cross-linking solution for 24 hours to ensure the surface was completely cross-linked. Collagen films were made by allowing the uncross-linked gels to dry overnight before and after NDGA treatment, resulting in a more compacted structure. A spinning disk device was employed to quantify the ability of cells to remain attached to the collagen samples when exposed to hydrodynamic forces. To avoid any cell-cell interaction and focus on cell-surface interactions, 50-100 cells/mm2 were seeded carefully on each sample. Temporal studies demonstrated that cell adhesion strength and spreading area reached steady-state by 4 hr. Adhesion and spreading studies along with migration experiments demonstrated that NDGA treatment affects cellular behavior on films, partially reducing adhesion strength, migration, and spreading area. However, on the cross-linked gels which are less dense, the only change in cell behavior observed was in migration speed. We hypothesize that these differences are due to the collapsing of the collagen films. This compaction suggests a less open organization and could be allowing the collagen fibers to form more inter-chain bonds as well as bonds with the small NDGA cross-linker; while NDGA treatment of the fully hydrated gels may rely more on NDGA polymerization to span the greater distance between collagen fibrils. From these results, we can determine that the chemical/physical masking of the adhesion sites by NDGA on collagen films affects cellular behavior more than the masking that occurs in the cross-linked gels. Although this study shows an effect in cell behavior on the cross-linked films, it also demonstrates that cells can adhere and migrate to this NDGA biomaterial supporting the idea that this biomaterial can be utilized for tendon replacement.

L’obiettivo della ricerca è promuovere una nuova concezione del volontariato che veda le associazioni non solo in chiave solidaristica, ma anche come organizzazioni che, con il loro fare, elaborano cultura ed attivano al proprio interno significativi processi di apprendimento per i propri associati. A tal fine si è inteso approfondire teoricamente il costrutto di Comunità di Pratica, per rintracciare le categorie che permettono di interpretare le associazioni di volontariato alla luce di questo concetto. In seguito, movendo dall’idea di associazione di volontariato come Comunità di Pratica, ci si è soffermati sulle sollecitazioni che offre e sui cambiamenti che può suscitare nei processi formativi avviati al proprio interno. / The research’s aim is to promote a new conception of volunteering that consider the associations not only as solidarity one, but also as organizations that develop culture by doing and that activate learning processes for their associated. To this aim I mean to study in the deep (theoretically) the concept of “Communities of Practice” to search the categories that allow to read the voluntary associations as Communities of Practice. Then I would like to dwell on the changes that the concept of “Communities of Practice” could promote in the training processes of the voluntary organizations.

Chitosan has proven through the years as a versatile biomaterial to be used in pharmaceutical applications. Its mucoadhesive properties as well as its ability to manipulate the tight junctions in epithelium membranes have qualified it as an effective drug carrier in controlled drug delivery systems. Microparticles or beads as they are forward called in this study have advantages over conventional drug dosage forms because of a large surface to volume ratio and have the ability to target a specific site for drug release. Indomethacin is an anti-inflammatory drug that causes gastrointestinal side effects in conventional immediate-release dosage forms. The goal is to manipulate the drug delivery vehicle to target the intestines/colon as the site for drug delivery and to minimize this side effect. Thus chitosan beads have been chosen as a drug delivery system for indomethacin in this study. Chitosan beads have been prepared through the ionotropic gelation method using tripolyphophate (TPP) as a cross-linking agent. To prepare the most effective bead to encapsulate indomethacin different formulation and system variables (pH of the TPP solution, the concentration of the TPP solution as well as the indomethacin concentration) have been evaluated according to the following parameters: morphology, drug loading capacity and swelling capability. The ideal pH of the TPP solution was determined at 8.7 and the most effective TPP and indomethacin concentration were 5% w/v and 4% w/v respectively. The chitosan concentration was kept at 3% w/v throughout the study. These concentrations were used to examine the effect of pharmaceutical excipients on the indomethacin release from chitosan beads. The effect of the different excipients namely, ExplotabⒽ(0.25% w/v), Ac-Di-SolⓀ (0.5% w/v) and Vitamin C (0.25% w/v), on the morphology, drug loading capacity, swelling capability as well as the drug release of indomethacin chitosan beads (ICB's) were also studied. The excipients were used in the individually above mentioned concentrations and in combination with each other in the same concentrations. These formulations were used in dissolution studies over a period of 6 hours in PBS pH 7.4 solutions. The indomethacin release rate increased when an excipient was added to the formulation and it dramatically increased when the excipients were added in their various combinations, compared to the formulation that did not contain excipients. / Contents: Chitosan -- Controlled drug delivery -- Indomethacin -- Inotropic gelation -- Tripolyphosphate (TPP) -- Explotab® -- Ac-Di-Sol® -- Vitamin C / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.

Controlled release systems aim at achieving a predictable and reproducible drug release over a desired time period. These systems allow reduced dosing frequency, constant drug levels in the blood, increased patient compliance and decreased adverse effects. In a recent study, Chitosan beads, containing N-trimethyl Chitosan chloride, have shown a potential in the delivery of rifampicin. However, because of inadequate amounts of rifampicin released over 24 hours, incorporation of other pharmaceutical excipients to increase the swelling behaviour of the beads to improve drug release, was considered in this study. Chitosan beads were prepared through ionotropic gelation with tripolyphosphate (TPP) as a crosslinking agent. To increase the porosity if the Chitosan beads Explotab®, Ac-Di-Sol® and vitamin C were added individually to Chitosan solutions at concentrations of 0.1, 0.25 and 0.5 % w/v before adding the mixture to the TPP solution. Swelling and morphology studies were used in the evaluation of the different formulations. The swelling and morphology results were then used to select a set of combination and concentrations of two excipients sand then prepare and characterise beads containing two combinations. The combination formulations and formulations containing single excipients were then loaded with rifampicin. Pure chitosan beads exhibited a higher drug loading capacity (67.49 %) compared to the lowest loading capacity of 41.61 % exhibited by chitosan beads containing a combination of Explotab®, Ac-Di-Sol®.For all the other formulations the drug loading capacity ranged within 48 and 63 %. These formulations were used for dissolution studies over a period of 6 hours at pH 5.60 and 7.40. The dissolution results showed that no chitosan has dissolved at both pH values. A significant amount of rifampicin was, however, released from the beads, especially at pH 7.40. chitosan beads containing vitamin C also exhibited high rifampicin release (48.34 ± 1.00) %) at pH 5.60 compared to the other formulations and this makes vitamin C a potential excipient for enhanced drug release over a wide pH range (both acidic and alkalinic). However, further studies are necessary to optimise the preparation method to minimise drug loss during loading and to improve the drug loading capacity of the beads. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2005.

In 1957, Canada's National Industrial Design Council (NIDC) organized a display for the Triennale di Milano, an international design exhibition in Milan. This exhibit focused on the development of the "new town" of Kitimat by the Aluminum Company of Canada (Alcan). Along with furnishings and photographs taken of the workers' and guests' quarters were objects that had received NIDC Design Awards. This display was one of many that represented a revitalized Canadian identity to an international audience. The Second World War had thrust Canada onto the international stage as an autonomous nation. Through its development of social, economic and cultural policies, the nation sought to extricate itself from its old world heritage and differentiate itself from its continental partner. By featuring Canada's "Aluminum City," the NIDC presented Canada as a modern nation that encouraged new industry and technology. Simultaneously, the physical location of Kitimat in the northern half of British Columbia enabled the designers to utilize a traditional element of Canadian identity—the North—in new ways. The landscape was now being civilized through the use of modern design and technology, rather than conquered by force. Finally, the juxtaposition of a photograph of a male Alcan worker, at the front of the display, with domestic objects in the display allowed for a blurring of traditional gender binaries. No longer a hard-hatted, hard-headed industrial worker; he was portrayed as a sophisticated individual working in a modern technological sphere in a civilized community. His presence signalled a rethinking of the contrasts between male and female, producer and consumer, public and private. Canada's display problematized these polarities and familiar elements of national identity through its use of domestic objects and furniture. My thesis investigates the suitability of blurring these traditional classifications in order to form a visual representation of Canadian identity in the immediate postwar period.