Improving the Public Health Information Network through Semantic Modeling

The US Centers for Disease Control and Prevention (CDC) created the Public Health Information Network to advance fully capable, interoperable information systems in public health organizations. PHIN prioritizes public health information systems' functional requirements, capabilities, performance measures, and operational characteristics while letting the architects of those systems choose enabling approaches, methods, and concepts to meet the requirements. PHIN also provides a certification process for public health administrators to evaluate their information infrastructure's quality. The certification process is important because affected organizations often depend on certification for continued funding.     

An example of a GAS system which can be destabilized by an integrable perturbation

A construction of a globally asymptotically stable time-invariant system which can be destabilized by some integrable perturbation is given. Besides its intrinsic interest, this serves to provide counterexamples to an open question regarding Lyapunov functions.     

Electromagnetic signatures as a tool for connectionless test

When we test boards, we usually think in terms of traditional electrical test (in-circuit, flying probe) and nonelectrical test (optical, x-ray). This Orebro University article develops an alternative, connectionless technique based on scanning the electromagnetic field generated by active on-board devices. Could this make it into industry as an additional diagnostic tool?.     

Phylogenetic scanning: a computer-assisted algorithm for mapping gene conversions and other recombinational events

An algorithm, 'phylogenetic scanning', is described for mapping gene conversion events where comparative DNA sequence data are available from different species. In this algorithm, sets of hypothetical phylogenetic trees are constructed that describe possible sequence relationships due to gene conversions in different species lineages; these trees are then evaluated by the principle of parsimony at intervals in the sequence alignment. When used to map gene conversion events that occurred between the pair of gamma-globin genes of higher primates, the algorithm gives results nearly identical to those obtained using a tedious manual approach. Suggestions are also provided for adaptation of this procedure to the analysis of other recombination events.     

Mechanism of the skeletal isomerisation of linear butenes over ferrierite: analysis of side reactions

An investigation of the effect of reaction conditions on product distribution in the skeletal isomerisation reaction of linear butenes has been carried out. The main reaction routes over ferrierite have been identified. Beside the main product isobutene, major by-product formation occurs. The unwanted reactions include dimerisation of butene to form octenes, hydrogen transfer yielding small amounts of saturated C₃ and C₄ hydrocarbons and disproportionation producing propene and pentenes. The most abundant by-products were pentene and propene, though these were not formed in equimolar amounts as could be expected. Oligomerisation experiments of propene over ferrierite produced large amounts of butene and pentene, revealing the presence of adsorbed nonene. The cracking of this surface species to hexene and propene is the most likely reaction route for the excess propene formation. This additional path to propene formation operates mainly at temperatures above 623 K.     

The Metaflow architecture

The Metaflow architecture, a unified approach to maximizing the performance of superscalar microprocessors, is introduced. The Metaflow architecture exploits inherent instruction-level parallelism in conventional sequential programs by hardware means, without relying on optimizing compilers. It is based on a unified structure, the DRIS (deferred-scheduling, register-renaming instruction shelf), that manages out-of-order execution and most of the attendant problems. Coupling the DRIS with a speculative-execution mechanism that avoids conditional branch stalls results in performance limited only be inherent instruction-level parallelism and available execution resources. Although presented in the context of superscalar machines, the technique is equally applicable to a superpipelined implementation. Lightning, the first implementation of the Metaflow architecture, which executes the Sparc RISC instruction set is described     

Materials technology for aerospace applications

Modern helicopter design depends on the successful combination of materials to fulfil a very wide range of critical functions. In the past few years demands from the aerospace industry have caused considerable enhancement in the favourable properties of both polymer based materials and metals. These are discussed in connection with the progressive technical evolution of helicopters and other advanced technological products from the Westland Group.     

Brazzein, a new high-potency thermostable sweet protein from Pentadiplandra brazzeana B

We have discovered a new high-potency thermostable sweet protein, which we name brazzein, in a wild African plant Pentadiplandra brazzeana Baillon. Brazzein is 2,000 times sweeter than sucrose in comparison to 2% sucrose aqueous solution and 500 times in comparison to 10% of the sugar. Its taste is more similar to sucrose than that of thaumatin. Its sweetness is not destroyed by 80 degrees C for 4 h. Brazzein is comprised of 54 amino acid residues, corresponding to a molecular mass of 6,473 Da.