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No description available.

The centromere binding factor 1, Cbf1, of Saccharomyces cerevisiae is a bHLH/ZIP protein which has been described as a determinant of specific chromatin structures and as a tethering factor for activators of transcription at the promoters of genes of the Methionine Biosynthesis Pathway. Deletion mutants show various phenotypes, among them methionine auxotrophy, an increased rate of chromosome loss, modifications in the growth rate and modification of the chromatin structure at MET genes. Meiosis competence also becomes greatly reduced in cbf1 cells. The sequence motif (RTCACRTG) to which Cbf1p binds is found at multiple loci through the yeast genome. This thesis shows that the chromatin structure is reorganised at multiple Cbf1p binding sites in vivo, when yeast cells are starved to enter meiosis. Extensive remodelling occurs at the MET16, MET17(25), DRS2 and GDH3 loci and at the YAL060W open reading frame, as detected by in vivo digestion of chromatin with micrococcal nuclease and indirect end-labelling. The same kind of analysis showed that the remodelling of chromatin at Cbf1p binding sites is not specific for meiosis, it occurs also in similarly starved haploid cells. The lack of methionine is a key trigger of these changes. This reorganisation of chromatin is dependent on Cbf1p, since starved cbf1 cells do not display any modification in nuclease accessibility patterns at or around Cbf1p binding sites. Mutational analysis revealed that a negative charge at a putative phosphorylation site (serine residue 226) and the DNA-bindmg activity of Cbf1p are both required for the chromatin reorganisation to occur in response to starvation. CBF1 mutants which do not reorganise chromatin were also shown to be unable to enter meiosis, suggesting that the remodelling of chromatin at multiple Cbf1p binding sites may be required to enter pre-meiotic DNA replication, since such cells arrest before the initiation of this process. In summary, the results presented in this thesis are compatible with a model in which Cbf1p plays an active role as part of a mechanism sensing the nutrient availability and regulates the reorganisation of chromatin, at multiple loci through the yeast genome, in response to starvation conditions.

In Saudi Arabia two massive and costly coastal land reclamations and developments were undertaken in the 1980s to define the borders of the expansion of two main coastal cities towards the sea. The first was started in the city of Jeddah on the Red Sea, and the second was started in the Dammam metropolitan area on the Arabian Gulf, to the west and the east of Saudi Arabia respectively. Two coastal roads were constructed on the shoreline of these two cities. ... Taking the case of the recreational sea front of the city of Dammam, and set against the background of the nature and history of recreational activity in Saudi Arabia, this study investigates the part played by the socio-cultural background of the local users of the sea front, and its effect on their picnicking behaviour there, in order to assist in providing appropriate information for landscape architects and other decision makers involved in the planning and design of outdoor leisure facilities in Saudi Arabia. ... The development of suitable recreational sea fronts, then, depends not only on the technical expertise of landscape architects, but also on a proper understanding of the role played by socio-cultural factors in the requirements of the users. Steps should be taken, both in the training of landscape architects and in the monitoring of plans for leisure areas, which will enable them to develop facilities which will be appropriate to the needs, aspirations, and values of their primary users, the local people. The potential for further study in this area exists. A quantitative approach could help establish more exact data about the preferences of local users of recreational facilities, and thus more precise criteria for their design. This would also help in site management. And the possibility exists for research into the impact of sea front developments on natural resources and ecology

Graduation date: 1976

Thesis (Ph. D.)--University of North Texas, Aug., 2007. / Title from title page display. Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 2007. / Full text release at OhioLINK's ETD Center delayed at author's request

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references. Also available via the Internet.

Thesis (Master)--İzmir Institute of Technology, İzmir, 2005. / Keywords: Archeological sites, stone, classification visual analysis, weathering forms.

Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains v, 90 p. : ill., map. Includes abstract. Includes bibliographical references (p. 65-68).