John Baptista

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Cell-mediated immunity and cytokines are probably involved in the pathogenesis of malaria. To investigate the role and the activity of different immune cells, we measured levels of tumour necrosis factor-(TNF-alpha), gamma interferon (IFN-gamma) and several interleukins (IL-2, IL-4, IL-6 and IL-10) in children with mild (MM) and cerebral (CM) Plasmodium(More)
The absence of a platform for secure electronic commerce is widely recognised. Across the globe, a host of Certification Authorities (CAs) have emerged to seize the opportunity for issuing digital certificates that constitute the Public Key Infrastructure (PKI). Yet the take-up of the technology has been bitterly disappointing. The market for digital(More)
Changes in lipid plasma levels during malaria attacks have been proposed for use in diagnosis or to assess the severity of the disease. In order to analyse the plasma levels of cholesterol, triglycerides, HDL-C et LDL-C, we compared, in an endemic area (São Tomé island), two groups of patients children infected with Plasmodium falciparum (simple malaria(More)
This paper deals with the question of how intranets impact on employee perception and behavior. The study uses a five year longitudinal study following the evolution of an intranet in a UK bank to analyze how it changed the relationships between employees and between managers and employees. The discussion integrates two different research domains, the(More)
The preparation of hydroxyapatite coatings on alumina substrates by a sol-gel method was investigated. A mixed ethanol solution of Ca(NO3)2.4H2O and P2O5 was used as a dipping source. The samples were characterized by solid-state 31P nuclear magnetic resonance spectroscopy, differential thermal analysis, thermogravimetry, X-ray diffraction, scanning(More)
Using a historical approach of malaria control in the island of São Tomé, the author describes the evolution of strategies used with special reference to the last 25 years. From a zero mortality rate in children under 4 years in 1981/83, malaria became the first cause of morbidity and mortality after the epidemic of 1985/86. Malaria was introduced in 1493,(More)
Public key infrastructure (PKI) has emerged as a critical technology for identity management in e-commerce and e-government and over a hundred Certification Authorities across the globe offer certification services. Despite the passing of legislation in many countries to give equal legal weight to electronic signatures as to handwritten ones, the overall(More)