Preliminary Design of Reactive Distillation Columns

A procedure that combines feasibility analysis, synthesis and design of reactive distillation columns is introduced. The main interest of this methodology lies on a progressive introduction of the process complexity. From minimal information concerning the physicochemical properties of the system, three steps lead to the design of the unit and the specification of its operating conditions. Most of the methodology exploits and enriches approaches found in the literature. Each step is described and our contribution is underlined. Its application is currently limited to equilibrium reactive systems where degree of freedom is equal to 2 or less than 2. This methodology which provides a reliable initialization point for the optimization of the process has been applied with success to different synthesis. The production of methyl-tert-butyl-ether (MTBE) and methyl acetate are presented as examples

Early outcome of facial reconstructive surgery abroad: a comparative study

Every year, many medical missions are undertaken in the developing world but there is almost a universal lack of outcome data on the quality of these missions. The present study compares early clinical outcome and complication rate in two consecutive missions (facial reconstruction) undertaken to Ethiopia in 2007 and 2008. The object was to establish if measures adopted following feedback from the first mission led to improvement of the results. A significant improvement was observed in early clinical outcome and there were less severe complications in the 2008 compared to the 2007 mission. On both occasions, significantly more complications were experienced after complex compared to simple procedures. Despite improved outcome in 2008, 50% of the complex cases had an unfavourable clinical result. The data suggest that early outcome studies are a useful method of critically evaluating the quality of surgical mission. The unsatisfactory outcome of complex procedures underlines the need for feedback on the quality of these missions

Daphnia parasite dynamics across multiple Caullerya epidemics indicate selection against common parasite genotypes

Studies of parasite population dynamics in natural systems are crucial for our understanding of host–parasite coevolutionary processes. Some field studies have reported that host genotype frequencies in natural populations change over time according to parasite-driven negative frequency-dependent selection. However, the temporal patterns of parasite genotypes have rarely been investigated. Moreover, parasite-driven negative frequency-dependent selection is contingent on the existence of genetic specificity between hosts and parasites. In the present study, the population dynamics and host-genotype specificity of the ichthyosporean Caullerya mesnili, a common endoparasite of Daphnia water fleas, were analysed based on the observed sequence variation in the first internal transcribed spacer (ITS1) of the ribosomal DNA. The Daphnia population of lake Greifensee (Switzerland) was sampled and subjected to parasite screening and host genotyping during C. mesnili epidemics of four consecutive years. The ITS1 of wild-caught C. mesnili-infected Daphnia was sequenced using the 454 pyrosequencing platform. The relative frequencies of C. mesnili ITS1 sequences differed significantly among years: the most abundant C. mesnili ITS1 sequence decreased and rare sequences increased over the course of the study, a pattern consistent with negative frequency-dependent selection. However, only a weak signal of host-genotype specificity between C. mesnili and Daphnia genotypes was detected. Use of cutting edge genomic techniques will allow further investigation of the underlying micro-evolutionary relationships within the Daphnia–C. mesnili system

Sicherheitsservice-Schicht

DE 10024347 A UPAB: 20020424 NOVELTY - The security service layer has a controller (60) for regulating communication, including the transmission of a message, based on a selected service routine. A selector (50) chooses the service routine from a number of available service routines based on the analyzed parameters of a produced message. DETAILED DESCRIPTION - A message device (30) produces a message, inclusive of descriptive parameters, for transmission from a client (10) to a target (20). An analyzer (40) processes the parameters of the message. An INDEPENDENT CLAIM is also included for the regulation of communication between client and target. USE - For regulating communication between client and target through communication channel e.g. bank transactions. ADVANTAGE - Requires reduced programming overhead and permits execution of applications on client page without having to deal with security issues. Permits further applications to run without consideration of support activities which are not security-related