Studies of fusicoccin chemistry

Imperial Users onl

Working Paper 93 - The Impact of High Oil Prices on African Economies

On the one hand the high price of oil is a unique opportunity for African oil producers to use the windfall gains to speed up their development. On the other hand, it is having adverse effects on net-oil importing countries, in particular those which cannot access international capital markets to smooth out the shock. We construct a dynamic stochastic general equilibrium model, which is tailored to reflect the characteristics of African economies, to quantify the effect of the increase in the price of oil on the main macro economic aggregates. The model is general enough that it imbeds both oil producing and oil importing countries. Our results indicate that a doubling of the price of oil on world markets with complete pass through to oil consumers would lead to a 6 per cent contraction of the median net-oil importing African country in the first year. If that country were to adopt a no-pass through strategy, output would not be significantly affected but its budget deficit would increase by 6 per cent. As for the median net oil exporting country, a doubling in the price of oil would mean that its gross domestic product would increase by 4 percent under managed-float and by 9 percent under a fixed exchange rate regime. However, inflation would increase by a much greater magnitude under managed than a fixed exchange rate regime in a median net oil exporting country.

Inorganic arrangement crystal beryllium, lithium, selenium and silicon

The use of inorganic crystals technology has been widely date. Since quartz crystals for watches in the nineteenth century, and common way radio in the early twentieth century, to computer chips with new semiconductor materials. Chemical elements such as beryllium, lithium, selenium and silicon, are widely used in technology. The development of new crystals arising from that arrangement can bring technological advances in several areas of knowledge. The likely difficulty of finding such crystals in nature or synthesized, suggest an advanced study of the subject. A study using computer programs with ab initio method was applied. As a result of the likely molecular structure of the arrangement of a crystal was obtained.Comment: 33 pages, 7 figure

Electromagnetic Wave Transmission Through a Subwavelength Nano-hole in a Two-dimensional Plasmonic Layer

An integral equation is formulated to describe electromagnetic wave transmission through a sub-wavelength nano-hole in a thin plasmonic sheet in terms of the dyadic Green's function for the associated Helmholtz problem. Taking the subwavelength radius of the nano-hole to be the smallest length of the system, we have obtained an exact solution of the integral equation for the dyadic Green's function analytically and in closed form. This dyadic Green's function is then employed in the numerical analysis of electromagnetic wave transmission through the nano-hole for normal incidence of the incoming wave train. The electromagnetic transmission involves two distinct contributions, one emanating from the nano-hole and the other is directly transmitted through the thin plasmonic layer itself (which would not occur in the case of a perfect metal screen). The transmitted radiation exhibits interference fringes in the vicinity of the nano-hole, and they tend to flatten as a function of increasing lateral separation from the hole, reaching the uniform value of transmission through the sheet alone at large separations.Comment: 14 pages, 24 individual figures organized in 9 captioned group

Book Review: Recognizing Transsexuals: Personal, Political and Medicolegal Embodiment

Review of Recognizing Transsexuals: Personal, Political and Medicolegal Embodiment by Zowie Dav

Molecular mechanism of action of newer thrombolytic agents

Recombinant tissue-type plasminogen activator (rt-PA) and single chain urokinase-type plasminogen activator (scu-PA) are thrombolytic agents, characterized by a high but not absolute degree of fibrin specificity that is mediated through different molecular mechanisms. Both activators are still under clinical investigation but it has become apparent that their therapeutic dose in humans is high and associated with a variable degree of systemic activation of the fibrinolytic system and fibrinogen breakdown. Therefore, the quest for further improvement of agents and therapeutic schemes continues. Research is being pursued in this area along the following lines: 1) tissue-type plasminogen activator (t-PA) and single chain urokinase-type plasminogen activator in molar ratios of 4:1 to 1:4 do not act synergistically on thrombolysis in a plasma environment in vitro, but display significant synergism in animal models of thrombosis. In pilot studies in patients with coronary artery occlusion, rt-PA and scu-PA are markedly synergistic and efficient thrombolysis can be obtained with a fivefold lower combined dose than that of the separate agents. The combined dose does not seem to induce systemic fibrinogen breakdown. 2) Deletion mutants of rt-PA can be constructed with a significantly prolonged half-life in vivo, and a better thrombolytic potential after bolus intravenous injection. 3) Cleavage site-specific mutants of scu-PA that abolish the conversion to urokinase may have a higher fibrin specificity. The mutants constructed thus far, however, seem to have a lower specific thrombolytic activity. 4) Chimeric molecules obtained by fusion of cDNA encoding the NH2-terminal region of t-PA, responsible for its fibrin affinity and cDNA encoding the COOH-terminal region of scu-PA, responsible for its enzymatic properties, combine both mechanisms of fibrin specificity, at least to some extent.It is anticipated that some of these research lines will yield improved thrombolytic agents or therapeutic regimens

Book Review: Palestinian Women: Narrative Histories and Gendered Memory

Review of Palestinian Women: Narrative histories and gendered memory by Fatma Kasse