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Reaction of iodosobenzene and trimethylsilyl chlorosulfonate followed by removal of the solvent and trimethylchlorosilane gives phenyliodosulfate. This can be used without further purification to prepare cyclic sulfates from alkenes, including vinylsilanes. Previous results have shown that if the trimethylchlorosilane is not removed, sulfones are formed and a possible explanation of this behaviour is given. Key words: silicon, vinylsilanes, cyclic sulfate, phenyliodosulfate.

The iron bioavailability from three typical diets consumed by socioeconomic stratum IV (SES IV - working class) of the Venezuelan population was determined by the extrinsic label method. Although the iron content of the SES IV diets was about the same (250 [[micro]mol]/d) as that of upper (SES I-III) and lower (SES V) socioeconomic strata diets, iron-replete subjects absorbed 43 and 61% more iron from the SES I-III diets than from the SES IV and V diets, respectively, and absorption from the main meal of the SES I-III diets was 100% greater. However, iron deficient subjects absorbed about the same amount of iron (45 [[micro]mol]/d) from the SES IV diets as from the SES I-III diets. The SES I-III diets contained more iron absorption enhancers (ascorbic acid and meat protein) and less of the inhibitor phytate, than the SES IV and V diets. Iron absorption from the meals of four diets consumed at different times during the day was also measured. There was no significant difference in the percentage iron absorption from the same meals eaten in the morning after an overnight fast, and when eaten at the customary time of day. INDEXING KEY WORDS: absorption; Venezuela; humans; iron; diet

We consider a virtual network (VN) embedding problem on a large-scale substrate physical network. We permit varying capacities and cost rates, and reservation of resources (physical links and nodes) for more profitable later VN requests. Our aim is to maximize the long-run average revenue by controlling the allocation of physical components to arriving VN requests. We propose an index policy that selects, according to state-dependent indices, a set of available physical components for each arrival. The indices are calculated in closed form requiring only intrinsic off-line information about physical components and physical resource requirements. Under reasonable assumptions related to rapidly increasing demands for VNs and resource competition, we show that this proposed policy is asymptotically optimal when the lifespans of embedded virtual components are exponentially distributed. Extensive numerical results demonstrate that the long-run average revenue earned by the proposed index policy rapidly approaches optimality: performance deviations between the index policy and the optimal solution are less than 5% in most of our simulations even for relatively small systems. Our numerical results also indicate that the long-run performance of this policy is relatively insensitive to the form of the lifespan distributions. [ABSTRACT FROM AUTHOR]

The active component of natural oil of wintergreen, used to relieve muscular pain, is methyl 2-hydroxybenzoate (methyl salicylate). It is most commonly available in solution with vegetable oil. It is possible to extract the active ingredient from the vegetable oil and hydrolyse it to give 2-hydroxybenzoic acid (salicylic acid), better known as aspirin. A project to turn oil of wintergreen into aspirin is presented.

The European Environment Agency (EEA) and environment indicators provide a comprehensive tool with which the integration of environmental considerations into European Union energy policy is assessed. The results show that in many areas of environmental integration there is some success, but overall progress is insufficient.

Byline: Peter G. Taylor, Hitendra Pillay, John A. Clarke The emerging knowledge-based society is transforming pedagogical practices in the post-compulsory education sector. One feature of this transformation is the substantial investment in new learning environments (NLEs), characterised by decreasing use of face-to-face teaching and a corresponding increase in use of information and communication technologies. While the rapid evolution of NLEs has been driven by economic/commercial forces and technological advances, and advocates claim enhanced learning outcomes, there is little critical understanding of how this is achieved or manifested. This paper reports empirically-based research that is seeking to develop a grounded understanding, from the learners' perspective, of the effects of participation in NLEs. The research site is an Australian purpose-built flexible learning mode university campus where web-based resources augment on-campus face-to-face activities. The research design involves a three-year longitudinal study of students, tracking their developmental patterns in perceptions, attitudes and beliefs. Data collection involves annual measures of learning approaches, perceptions of learning environments and epistemological reflections, along with biannual group interviews. Outcomes of aspects of the first year data are reported, highlighting patterns in students' reactions not evident in previous literature and which have potentially significant pedagogical implications.

Highlights • Many governments are pursuing increasingly active industrial strategies. • The Paris Agreement requires urgent action on low carbon transformations. • Low Carbon Industrial Strategies can combine socio-economic and environmental goals. • Neo-Schumpeterian theories inform states' support for mission-oriented innovation. • Ecological Economics highlights need for low carbon and circular economy. Abstract The recent re-emergence of industrial policy as a legitimate pursuit of governments in Europe and the US has the potential to open up a new realm of policy action for climate change mitigation. This would aim to align efforts to secure national industrial opportunities with the development of low carbon industrial systems, so as to generate both socio-economic and environmental benefits. The paper discusses the role of low carbon industrial strategy in seeking to do this, thereby accelerating transitions to a low carbon economy. It sets out the elements of a more systemic low carbon industrial strategy, including providing a mission-oriented and learning-based approach, drawing on and combining insights from neo-Schumpeterian and ecological economics perspectives. [ABSTRACT FROM AUTHOR]

Reported herein is the development of assays for the spectrophotometric quantification of biocatalytic silicon−oxygen bond hydrolysis. Central to these assays are a series of chromogenic substrates that release highly absorbing phenoxy anions upon cleavage of the sessile bond. These substrates were tested with silicatein, an enzyme from a marine sponge that is known to catalyse the hydrolysis and condensation of silyl ethers. It was found that, of the substrates tested, tert-butyldimethyl(2-methyl-4-nitrophenoxy)silane provided the best assay performance, as evidenced by the highest ratio of enzyme catalysed reaction rate compared with the background (uncatalysed) reaction. These substrates were also found to be suitable for detailed enzyme kinetics measurements, as demonstrated by their use to determine the Michaelis−Menten kinetic parameters for silicatein. [ABSTRACT FROM AUTHOR]