Home About us Contact
|
Home About us Contact | ||
|
|
||
Optimal Protection (optimal + protection)
Selected AbstractsThe Choice of Optimal Protection under Oligopoly: Import Tariff v. Production SubsidyTHE JAPANESE ECONOMIC REVIEW, Issue 3 2002Tsuyoshi Toshimitsu Economists researching the area of optimal protection have tended to analyse the ranking of alternative policy tools in the presence of perfect competition, either when the government in an importing country achieves a non-economic target, or when there is a market distortion. Assuming international oligopolistic competition, I reconsider the choice of optimal policy instruments, i.e. an import tariff and a production subsidy. I show that the choice of optimal policy instruments depends on the relative number of home firms and foreign ones and on the magnitude of international cost differences. JEL Classification Numbers: F12, F13. [source] A simple model for the interaction between water vapour and oxygen transmission in multilayer barrier materials intended for food packaging applicationsPACKAGING TECHNOLOGY AND SCIENCE, Issue 4 2008Marianne Jakobsen Abstract The low oxygen permeability of the ethylene-vinyl alcohol copolymer, EVOH, is outstanding, but is also known to be very sensitive to moisture uptake and cannot be used as a monolayer packaging material. In this paper, theory is presented in order to calculate the average water activity of the EVOH layer at steady state and the corresponding oxygen barrier for different multilayer structures using various polymer types and layer thicknesses. Multilayer materials can be designed for different food packaging applications and storage conditions, in order to keep the relative humidity of the barrier below recommended 75%, by varying the thickness of the outside versus the inside protective layers and/or varying the water vapour transmission rate of the outside versus the inside layer. The conclusion reached is that to retain the optimal barrier properties and thereby the optimal protection of the food, asymmetric multilayer structures are necessary. Copyright ©2007 John Wiley & Sons, Ltd. [source] GRA7 provides protective immunity in cocktail DNA vaccines against Toxoplasma gondiiPARASITE IMMUNOLOGY, Issue 9 2007E. JONGERT SUMMARY In a previous study, single-gene vaccination with GRA1, GRA7 or ROP2 was shown to elicit partial protection against Toxoplasma gondii. In this study, the contribution of each antigen in the evoked humoral and cellular immune responses was evaluated after vaccination with plasmid mixtures containing GRA1, GRA7 and ROP2. Cocktail DNA vaccinated mice developed high antibody titers against the antigens from two-gene DNA vaccine cocktails, but lower titres when immunized with the three-gene cocktail. High numbers of IFN-, secreting splenocytes were generated predominantly against GRA7. Brain cyst burden was reduced by 81% in mice vaccinated with the three-gene mixture and they were completely protected against acute toxoplasmosis. Similar high levels of brain cyst reductions were obtained after vaccination with cocktails composed of GRA1 and GRA7 (89% reduction), or GRA7 and ROP2 (79% reduction), but not with the cocktail composed of GRA1 and ROP2. In low dose single-gene vaccinations, IFN-, and strong protection could only be elicited by GRA7. Hence, the presence of GRA7 in the DNA vaccine formulation was important for optimal protection and this was correlated with GRA7-specific IFN-, production. We propose GRA7 as a main component in cocktail DNA vaccines for vaccination against T. gondii. [source] Antigen presentation and dendritic cell biology in malariaPARASITE IMMUNOLOGY, Issue 1-2 2006M. M. STEVENSON SUMMARY Dendritic cells (DCs) are important both in amplifying the innate immune response and in initiating adaptive immunity and shaping the type of T helper (Th) response. Although the role of DCs in immune responses to many intracellular pathogens has been delineated and research is underway to identify the mechanisms involved, relatively little is known concerning the role of DCs in immunity to malaria. In this review, we provide an overview and summary of previous and current studies aimed to investigate the role of DCs as antigen presenting cells (APCs). In addition, the role of DCs in inducing innate and adaptive immunity to blood-stage malaria is discussed and, where information is available, the mechanisms involved are presented. Data from studies in humans infected with Plasmodium falciparum, the major human parasite responsible for the high morbidity and mortality associated with malaria throughout many regions of the developing world, as well as data from experimental mouse models are presented. Overall, the data from these studies are conflicting. The possible reasons for these differences, including the use of different parasite species and parasite strains in the mouse studies, are discussed. Nevertheless, together the data have important implications for development of an effective malaria vaccine since the selection of appropriate Plasmodium antigens and/or adjuvants, targeting innate immune responses involving DCs, may provide optimal protection against malaria. It is hoped that this review promotes more investigation among malariologists and immunologists alike on DCs and malaria. [source] The Choice of Optimal Protection under Oligopoly: Import Tariff v. Production SubsidyTHE JAPANESE ECONOMIC REVIEW, Issue 3 2002Tsuyoshi Toshimitsu Economists researching the area of optimal protection have tended to analyse the ranking of alternative policy tools in the presence of perfect competition, either when the government in an importing country achieves a non-economic target, or when there is a market distortion. Assuming international oligopolistic competition, I reconsider the choice of optimal policy instruments, i.e. an import tariff and a production subsidy. I show that the choice of optimal policy instruments depends on the relative number of home firms and foreign ones and on the magnitude of international cost differences. JEL Classification Numbers: F12, F13. [source] Virus-specific CD8 T cells: activation, differentiation and memory formationAPMIS, Issue 5-6 2009MELANIE WIESEL CD8 T cells are pivotal for the control of many intracellular pathogens, and besides their role in immediate control of infections, CD8 T cells have the capacity to differentiate into long-lived antigen-independent memory CD8 T cells, at least in situations of acute and resolved infections. The population of memory cells is heterogeneous with respect to their phenotype, their anatomical localization and their functional capacities in order to afford optimal protection against secondary infections. In the past years, it has become clear that multiple in vivo parameters are involved in shaping the composition of the memory CD8 T cell population, including antigen load, duration and strength of CD8 T cell stimulation, the level of inflammation, availability of CD4 T cell help and CD8 T cell precursor frequencies. With respect to the timing when CD8 T cells are committed to become memory cells, several models have been proposed. In contrast to acute, resolved infection, the continued in vivo exposure to high levels of antigen during persistent chronic viral infection precludes the development of long-lived antigen-independent memory CD8 T cells and might even result in severe dysfunction of virus-specific CD8 T cells. [source] | ||||||||||