Liposomal cationic charge and antigen adsorption are important properties for the efficient deposition of antigen at the injection site and ability of the vaccine to induce a CMI response

With respect to liposomes as delivery vehicles and adjuvants for vaccine antigens, the role of vesicle surface charge remains disputed. In the present study we investigate the influence of liposome surface charge and antigen-liposome interaction on the antigen depot effect at the site of injection (SOI). The presence of liposome and antigen in tissue at the SOI as well as the draining lymphatic tissue was quantified to analyse the lymphatic draining of the vaccine components. Furthermore investigations detailing cytokine production and T-cell antigen specificity were undertaken to investigate the relationship between depot effect and the ability of the vaccine to induce an immune response. Our results suggest that cationic charge is an important factor for the retention of the liposomal component at the SOI, and a moderate to high (>50%) level of antigen adsorption to the cationic vesicle surface was required for efficient antigen retention in the same tissue. Furthermore, neutral liposomes expressing poor levels of antigen retention were limited in their ability to mediate long term (14 days) antigen presentation to circulating antigen specific T-cells and to induce the Th1 and Th17 arms of the immune system, as compared to antigen adsorbing cationic liposomes. The neutral liposomes did however induce the production of IL-5 at levels comparable to those induced by cationic liposomes, indicating that neutral liposomes can induce a weak Th2 response.

Parameters for tool life optimisation with respect to face milling

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An optimum utilisation of plant and equipment with respect to maintenance

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Determinants of Firm Growth with respect to Exporting and Innovation Activities: Evidence from Egyptian SMEs

Small and medium-sized enterprises (SMEs) are considered to be the driving engine for employment growth, source of innovation and technological progress. Moreover, the success of small exporters is critical for economic growth and is considered as an important development stage for many SMEs. However, their competitive advantage lies within the firm’s ability to innovate. This thesis contributes to the above literature by examining two main factors believed to promote firm growth namely ‘exporting’ and ‘innovation’ activities. Growing interests on the relationship between exporting, innovation and growth have recently been tackled. However, there remains a gap in literature on the relationship between exporting, innovation and firm growth for SMEs in emerging economies. Previous studies are conducted in developed counties such as UK, Ireland, USA, Germany, and Switzerland, which leaves the gap for those developing countries. Thus, this thesis addresses the gap by examining the importance of innovation and exporting activities in the growth of SMEs in Egypt. It is also the researcher’s intent to recognise the unique contribution of innovation on firm exporting activities covering all sectors. gypt, one of the countries that were tremendously affected by the so-called ‘Arab Spring revolution’, is suffering from slow economic growth, high unemployment and poverty rate. Thus, the government must ensure economic growth and job creation. Programmes to encourage and develop SMEs should be part of inclusive growth strategy. Meanwhile, exporting is regarded as a key factor to help the economy recover from recession and stimulate economic growth. On the other hand, innovation leads to better performance in terms of growth, exporting and productivity. Therefore, SMEs and their exporting and innovation activities should be an integral part of any recovery and growth strategy for the economy. Moreover, Egypt is suffering from the so-called ‘Missing Middle’, which is problematic as medium firms tend to provide better employment growth and productivity. Therefore, more light is to shed on the importance of exporting and innovation in the growth of firms. The research design was quantitative in nature, testing the proposed hypotheses. The study was conducted in 2013 based on questionnaires of 406 Egyptians SMEs. The results of the empirical study suggest that both exporting and innovation activities are important in firm growth. However, the results show that, after controlling for endogeneity, innovation does not affect exporting activities in SMEs.