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L’intérêt de l’irradiation des ganglions lymphatiques pelviens est débattu pour les patients atteints d’un cancer de la vessie infiltrant le muscle (TVIM) bénéficiant d’une radiothérapie (RT) à visée curative. L’objectif de notre étude était de comparer les résultats oncologiques entre la RT de la vessie seule (VO) et la RT vessie et pelvis (WP) à l’aide d’une base de données collaborative multicentrique canadienne.

AbstractThe logical and pragmatic outcome of social theories of editing, as has been suggested, is editions that take into account the materiality of the text to such a degree that they can exist only immaterially, in the electronic realm. This paper explores a juncture, one at which the accumulation of textual archival materials associated with social theories of editing meet their natural home in the electronic scholarly edition, and one at which large collections of materials in electronic form meet their equivalent in the world of the ever-growing body of scholarschip, available in electronic form, that is associated with the primary materials that lie at the heart of the textual scholar's concerns. With the electronic medium embraced editorially, the next major concern to be addressed by those interested in the edition, especially those exemplary textual scholars who have invested significant effort accumulating digital archival material, is the proper navigation of that material.

We have prepared a series of cross-linkable oligo- and poly(dialkylfluorene)s by nickel(0)-mediated polymerization of 2,7-dibromo-9,9-dialkylfluorene (alkyl = n-hexyl) and 4-bromostyrene. The resulting fully soluble and processable, styryl-functionalized oligomers and polymers can be cross-linked via the vinyl end-groups by curing at 175−200 °C, consistent with the autopolymerization mechanism of styrene. These relatively mild conditions render the materials insoluble and enable multilayering of polymers in organic light emitting devices. At the same time, the electrical and/or optical properties of the cross-linked polymers are preserved and no deleterious species or undesirable byproducts are produced. Furthermore, the cross-linking allows control of the supramolecular ordering of the planarized rigid rod-type fluorene segments in the polymer backbone that leads to suppression of troublesome excimer/aggregate in the photo- and electrolumenescence.

Several new approaches to biodegradable dendritic aliphatic block copolymers are described, including hyperbranched and dendrimer-like star structures. The hyperbranched polymers were obtained by the co-condensation of different AB2 macromonomers. The macromonomers were prepared by ring-opening polymerization (ROP) of either ε-caprolactone, l-lactide, or various substituted lactones using the benzyl ester of 2,2‘-bis(hydroxymethyl)propionic acid as initiator. Catalytic hydrogenation of the benzyl ester generated the requisite acid functional AB2 macromonomer. The second route utilizes a new type of molecular architecture, denoted as dendrimer-like star polymers. These block copolymers are described by a radial geometry where the different layers or generations are comprised of high molecular weight polymer emanating from a central core. With this architecture, more control in the placement of the different blocks is afforded over the hyperbranched analogue. As a means of imparting desirable mechanical properties to the dendritic copolymers, a series of new substituted lactones were prepared. The use of such monomers prevents crystallization of the poly(lactone), allowing dendritic polyesters with a range of mechanical properties from thermoplastic elastomers to rubber toughened systems, depending on the relative composition of the two components. The synthesis, characterization, and morphology of these new copolymers are discussed.

Thin films of rigid poly(p-phenylene pyromellitimide) (PMDA-PDA) and semi-rigid poly(p-phenylene biphenyltetracarboximide) (BPDA-PDA), prepared by thermal imidization of the respective poly(amic acid) and poly(amic ethyl ester) precursors, were characterized with respect to their optical, thermomechanical and structural properties. Both polyimides exhibit an unusually large anisotropy between the in-plane and out-of-plane refractive indices, with ?n ranging from 0.198 to 0.216 for PMDA-PDA and from 0.230 to 0.242 for BPDA-PDA, nearly independent of the nature of the initial polyimide precursor, film thickness, and film preparation method. PMDA-PDA films exhibit low coefficients of thermal expansion (CTE's) of 6.5 and 8.2 ppm/dC for the acid-derived and the ester-derived polyimides, respectively. In comparison, the BPDA-PDA films show CTE values of 4.3 and 18.0 for the acid-derived and ester-derived samples, respectively, despite the small differences in their optical anisotropies. Wide-angle x-ray diffraction patterns obtained in reflection and transmission for the various samples reveal a strong in-plane chain orientation for both PMDA-PDA and BPDA-PDA polyimides, with somewhat better intermolecular packing order for the ester-derived polyimide films. These effects of chemical structure and precursor on properties and structures of the polyimide films are discussed in light of recent theoretical considerations of semiflexible polymers.

Examination of the thermal transitions, decomposition rate, and softenin temperature of Poly (p-oxybenzoate) indicates a process window of several minutes near 440d`C where the powder can be compression molded. The nature of the thermal transitions and modeling time, Pressure, and temperature aimed at achieving the optimum flow properties are discussed

X-ray lithography using synchrotron radiation has been applied in a multi-step process for the production of plastic moulds to be used in the fabrication of separation nozzles by electrodeposition. For characteristic dimensions of a few microns a total height of the nozzle structure of about 400 µm has been achieved. Structural details of about 0.1 µm are being reproduced across the total thickness of the polymer layer. The surface finish of metallic separation nozzles produced by electrodeposition was equivalent to the high quality of the polymer surface. The separation-nozzle systems fabricated by the described method allow an increase by a factor three of the gas pressure in separationnozzle plants as compared to the present standard. This results in considerable savings in the enrichment of 235U for nuclear power production.