The transnational Gulf City: Saudi and migrant values of public open spaces in Jeddah

This paper outlines patterns of use, perceived benefits and place attachment relating to public open space in Jeddah, Saudi Arabia, a city in which almost half the residents are born overseas. The methods included case studies representing different recreational landscape typologies, observational analysis and 85 on-site interviews (46% Saudi, 54% migrants). The findings outline the benefits of visiting as a retreat from busy lifestyles, for everyday sociability, for improving health, for religious practice and for mutual support, highlighting dimensions of gender, transnationality and heritage. The paper explores place attachment related to displacement comparing between impacts of migration and of rapid urbanisation. The narratives suggest that experiences shaped by temporality and memory inform emotional geographies for both Saudi and migrant residents. There are differences in patterns of use between resident groups, but the paper concludes that, within a highly stratified society, the public open spaces of Jeddah provide an important resource of shared pleasures and everyday multiculture

MOLECULAR MECHANICS OF CYTOSKELETAL COMPONENTS

Summary Semiflexible polymers are of great biological importance in determining the mechanical properties of cells. We have used laser interferometry to passively trap and detect the motions of pairs of micron sized silica spheres in solutions of semiflexible polymer. The single-and dual-bead frequency dependent complex shear moduli were extracted from the auto-and cross-correlation response of the beads respectively, with the response being derived from position fluctuation data using dispersion relations from linear response theory

Association of IL-1beta gene polymorphism with cachexia from locally advanced gastric cancer

BACKGROUND: IL-1beta has been implicated in inflammatory episode. In view of the inflammatory nature of cancer cachexia, we determined the predictive value of IL-1B-31 T/C, -511 C/T, +3954 C/T and IL-1RN VNTR gene polymorphisms on the occurrence of cachexia associated with locally advanced gastric cancer. METHODS: The study included 214 patients and 230 healthy volunteers. Genomic DNA was prepared from peripheral blood leukocytes. Genotypes and allele frequencies were determined in patients and healthy controls using restriction fragment length polymorphism analysis of polymerase chain reaction products. RESULTS: The overall frequencies of IL-1B-31 T, -511 T, +3954 T and IL-1RN VNTR alleles in patients with locally advanced gastric cancer were all comparable with those in controls. No significant differences were found in the distribution of IL-1B-31 T, -511 T and IL-1RN VNTR between patients with cachexia and without. Patients with cachexia showed a significantly higher prevalence of IL-1B+3954 T allele than those without (P = 0.018). In a logistic regression analysis adjusted for actual weight, carcinoma location and stage, the IL-1B+3954 CT genotype was associated with an odds ratio of 2.512 (95% CI, 1.180 – 5.347) for cachexia. CONCLUSION: The IL-1B+3954 T allele is a major risk for cachexia from locally gastric cancer. Genetic factors studied are not likely to play an important role in the determination of susceptibility to locally advanced gastric cancer

Twin optical traps for two-particle cross-correlation measurements: Eliminating cross-talk

The correlated motions of two micron-sized particles reflect the (micro-) rheological properties of a fluid and can be conveniently detected using two optical traps in combination with interferometric displacement detection. When the correlations become small, cross-talk between the two beams becomes important. We have used dual optical traps created by either two orthogonally polarized laser beams derived from one laser source, or by two independent lasers of different wavelengths for microrheology experiments. High numerical aperture lenses (objective and condenser) in the optical path can introduce depolarization, and polarizing beam splitters are not perfect, both of which can lead to optical cross-talk. We have characterized the cross-talk in our setup and demonstrate that the use of two independent laser eliminates cross-talk entirely. © 2008 American Institute of Physics

Microrheology of solutions of semiflexible biopolymer filaments using laser tweezers interferometry

A microrheology technique was developed to measure the viscoelastic properties of solutions of submicroiliter volumes. A microrheology technique which employs laser beam to trap a micron-sized silica bead was discussed. The shear moduli of solutions of fd viruses, which are filamentous, semiflexible and monodisperse bacteriophages were measured using a particle tracking microrheology technique. The results show that in dilute solutions shear modulus is dominated by rotational relaxation