The application of foresight to address the challenges of uncertainty and rapid change has grown dramatically in the past decade. In that period, the techniques have been greatly refined and the ...scope has been broadened to encompass future-oriented technology analysis (FTA) and more recently, the concept and practice of strategic intelligence. FTA addresses directly the longer-term future through the active and continuous development of visions, and pathways to realise these visions. It is increasingly seen as a valuable management and policy tool complementing, and extending further into the future, classical strategy, planning, and decision-making approaches. This book charts the development of FTA and provides the first coherent description and analysis of its practical application and impact in the worlds of business, government, education and research in both advanced and developing countries. It draws on papers addressing the application of FTA around the globe which were presented at the Second International Seville Seminar in September 2006. The insights and practical experience will be invaluable for company managers, government ministers and officials, researchers and academics with responsibilities for effective planning and decision-making in an increasingly turbulent and unpredictable world.
A modified posterior lumber interbody fusion procedure is described: this technique basically uses only two tricortical bone grafts and does not produce a distraction at the interspace while ...inserting the bone grafts. Twenty patients with intractable back and leg pain due to an isthmic spondylolysis and a grade 1 spondylolisthesis were operated using this technique and a prospective study with a mean follow-up of 41 months was conducted to evaluate the results. The final evaluation involved a questionnaire, a clinical examination, and a lumbar spine radiographic series. Fourty-five percent of the patients had good or excellent results whereas 55% had fair or poor results. The possible reasons for these unfavorable results are discussed.
This retrospective study evaluates visual (functional) and refractive outcome of correcting hyperopia (i.e. 2.5 D or more) by means of a cataract procedure and simultaneously the pre-existing ...clinical significant astigmatism (1.5 D or more with the rule; 1 D or more against the rule), if present, by means of an arcuate keratotomy. Nine eyes undergoing clear lens extractions with intraocular lensimplantation (IOL) in combination with arcuate keratotomy (group one) and 29 eyes without arcuate kertotomy (group two) are included in the study. The mean age at the time of surgery was 62.89 years (range, 50 to 83) in group one and 68.17 years (range, 53 to 86) in group two. For calculation of the lens power a modified SRK II program, aiming at emmetropia was used. In only one highly hyperopic patient the Holladay I formula was used to calculate two piggyback lenses. A modified Istre nomogram was used to determine the surgical parameters of the arcuate keratotomy. The Cravy formula and the Holladay, Cravy, Koch vector analysis were used to determine the change in refractive cylinder results. Patients were followed postoperatively for a mean of 2.8 months in group one and 7.5 months in group two. In group one, 6 out of 9 eyes achieved a postoperative refraction within +/- 0.5 D of intended refraction and 8 out of 9 were within +/- 1 D of intended refraction. In group two, it was 15/29 and 24/29 respectively. Postoperatively, the uncorrected visual acuity was 20/40 or better in all eyes of group one (9/9) and in 27/29 eyes of group two. None of the eyes in both groups lost two or more lines of the best corrected visual acuity. Clear lens extraction with IOL is an effective and safe procedure for the correction of hyperopia in a presbyopic age group. In combination with an arcuate keratotomy, pre-existing astigmatism can be corrected simultaneously.
We present a detailed study based on infrared photometry of all Galactic RV Tauri stars from the General Catalogue of Variable Stars (GCVS). RV Tauri stars are the brightest among the population II ...Cepheids. They are thought to evolve away from the asymptotic giant branch (AGB) towards the white dwarf domain. IRAS detected several RV Tauri stars because of their large IR excesses and it was found that they occupy a specific region in the 12 - 25, 25 - 60 IRAS two-colour diagram. We used the all sky survey of WISE to extend these studies and compare the infrared properties of all RV Tauri stars in the GCVS with a selected sample of post-AGB objects with the goal to place the RV Tauri pulsators in the context of post-AGB evolution. Moreover, we correlated the IR properties of both the RV Tauri stars and the comparison sample with other observables like binarity and the presence of a photospheric chemical anomaly called depletion. We find that Galactic RV Tauri stars display a range of infrared properties and we differentiate between disc sources, objects with no IR excess and objects for which the spectral energy distribution (SED) is uncertain. We obtain a clear correlation between disc sources and binarity. RV Tauri stars with a variable mean magnitude are exclusively found among the disc sources. We also find evidence for disc evolution among the binaries. Furthermore our studies show that the presence of a disc seems to be a necessary but not sufficient condition for the depletion process to become efficient.
Context: This paper is part of a larger project in which we study the chemical abundances of extra-galactic post-AGB stars with the ultimate goal of improving our knowledge of the poorly understood ...AGB third dredge-up mixing processes and s-process nucleosynthesis. Aims: In this paper, we study two carefully selected post-AGB stars in the LMC. The combination of favourable atmospheric parameters for detailed abundance studies and their known distances make these objects ideal probes of the internal AGB third dredge-up and s-process nucleosynthesis in that they provide observational constraints for theoretical AGB models. Methods: We use high-resolution optical UVES spectra to determine accurate stellar parameters and perform detailed elemental abundance studies. Additionally, we use available photometric data to construct SEDs for reddening and luminosity determinations. We then estimate initial masses from theoretical post-AGB tracks. Results: Both stars show extreme s-process enrichment associated with relatively low C/O ratios of about 1.3. We could only derive upper limits of the lead (Pb) abundance which indicate no strong Pb overabundances with respect to other s-elements. Comparison with theoretical post-AGB evolutionary tracks in the HR-diagram reveals that both stars have low initial masses between 1.0 and 1.5 Msun. Conclusion: This study adds to the results obtained so far on a very limited number of s-process enriched post-AGB stars in the Magellanic Clouds. We find an increasing discrepancy between observed and predicted Pb abundances towards lower metallicities for all studied Magellanic Cloud post-AGB stars found so far, as well as moderate C/O ratios. We find that all s-process rich post-AGB stars in the LMC and SMC studied so far, cluster in the same region of the HR-diagram and are associated with low-mass stars with a low metallicity on average.
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