New development: scarcity, policy gambles, and ‘one-shot bias’—training civil servants to speak truth to power

Allocating scarce resources to meet policy objectives incurs opportunity costs. A vital element of ‘speaking truth to power’ thus involves officials advising ministers on the opportunity costs of high-risk ‘pet projects’. In democracies, the brevity of ministerial office can produce ‘one-shot bias’—radical policy-making that deploys ministers’ time-limited powers to the full, yet risks producing significant opportunity costs for public service organizations. Examples include the UK’s recent social security, healthcare and European policies. Training in the economics of organization, development of new techniques for coping with uncertainty in opportunity-cost estimates, and stronger incentives for decision-makers to consider ‘benefits foregone’ by their actions could all provide greater protection against the downsides of one-shot bias

Research and calibration of Acoustic Sensors in ice within the SPATS (South Pole Acoustic Test Setup) project

We present development work aiming towards a large scale ice-based hybrid detector including acoustic sensors for the detection of neutrinos in the GZK range. A facility for characterization and calibration of acoustic sensors in clear (bubble-free) ice has been developed and the first measurements done at this facility are presented. Further, a resonant sensor intended primarily for characterization of the ambient noise in the ice at the South Pole has been developed and some data from its performance are given.Comment: 4 pages, 8 figures, ARENA 2010 conference proceeding

Uncertainty quantification of coal seam gas production prediction using Polynomial Chaos

A surrogate model approximates a computationally expensive solver. Polynomial Chaos is a method to construct surrogate models by summing combinations of carefully chosen polynomials. The polynomials are chosen to respect the probability distributions of the uncertain input variables (parameters); this allows for both uncertainty quantification and global sensitivity analysis. In this paper we apply these techniques to a commercial solver for the estimation of peak gas rate and cumulative gas extraction from a coal seam gas well. The polynomial expansion is shown to honour the underlying geophysics with low error when compared to a much more complex and computationally slower commercial solver. We make use of advanced numerical integration techniques to achieve this accuracy using relatively small amounts of training data

Usability context analysis: a practical guide

The usability of a product is affected not only by the features of the product itself, but also by the characteristics of the users, the tasks they are carrying out, and the technical, organisational and physical environment in which the product is used. In this guide, we use the term 'context' to include all factors which affect the usability of the product, excluding the features of the product itself. We use the term 'product' to represent any interactive system or device designed to support the performance of users' tasks

Azulene-based Protecting Groups

Protecting groups form an indispensable part of modern organic synthetic chemistry. Besides the benefits of selectively passivating certain reactive functionalities, they often provide handling benefits – such as a decrease in the polarity of the compound that facilitates purification, an increase in the structural order of a compound that allows for easier crystallisation, and chromophores that enable easy visualisation on fluorescent TLC plates under UV light. Coloured protecting groups offer additional advantages in synthetic chemistry. They expedite purification by allowing the material to be tracked visually. Phase separation and column chromatography are easier to perform, and reduce the need for the collection of large numbers of fractions, while small-scale loss of material (left behind on taps or in flasks during routine handling) and spillages are much more readily apparent. Despite these advantages, only a few coloured protecting groups have been reported in the literature. The azulenes are a class of compounds with several attractive qualities that can be exploited for use as protecting groups. They are coloured, but not overwhelmingly so. The colour is tunable through placement of electron-donating or electron-withdrawing groups at positions on the ring system, which further allows for protection/deprotection reactions to be designed that incorporate a colour change. Azulene itself is both non-polar and structurally compact, unlike many other organic chromophores such as triarylmethane dyes and carotenoids. Furthermore, azulene’s ability to stabilise both positive and negative charges through resonance with tropylium and cyclopentadienide motifs allows for unusual chemistry, and therefore potentially orthogonal modes of deprotection. Four protecting group candidates incorporating azulene were devised. The 1-azulenylmethylene amine 79 and the 1-azulenesulfonamide 82 protecting group candidates for amines had fatal flaws that were discovered early, such as a tendency to rapidly degrade in open air. The 1-azulenecarboxylate protecting group candidate 74 for alcohols showed some promise, with a high-yielding protection reaction, but none of the deprotection conditions that were developed were sufficiently mild to be usable in a late-stage deprotection strategy on a complex target molecule. The final protecting group candidate, 6-(2-[oxycarbonyl]ethyl)azulene 89, can be used for the protection of carboxylic acids, amines and alcohols as esters, carbamates and carbonates, respectively. The substitution at the 6-position of azulene allows for deprotection through an E1cB mechanism with mild base, involving a cyclopentadienide-stabilised carbanion intermediate, in a similar fashion to the FMOC protecting group. Mild conditions for the protection of all three were found: for carboxylic acids Steglich esterification is employed, and for alcohols and amines coupling with CDI is used. A selection of mild protocols for deprotection were developed, using bases such as DBU or TBAF, or involving two-step activation-deprotection procedures. Finally, the compatibility of the protecting group 89 (dubbed Azul) with common and representative procedures in synthetic chemistry was investigated, such as with bases and with reaction conditions such as oxidations, reductions, cross-couplings, etc. Orthogonality with other common protecting groups (such as TBS, MOM, FMOC) was also explored. Some incompatibilities were found with strongly acidic conditions, high-temperature Suzuki cross-coupling reactions and Swern oxidations, but otherwise the Azul protecting group shows promise as a protecting group that expedites total synthesis through its colourful properties

Investigations of Azulene Derivatives as Self-Indicating Chromophores for Applications in Protecting Group Strategies and Solid-Phase Purification

Azulene is a hydrocarbon that exhibits an intense blue colour. Derivatives of azulene exhibit different colours depending on the position and electronic properties of the substituents. The chemical and chromophoric properties of azulene and guaiazulene derivatives are investigated for the potential use in applications such as chromophoric protecting groups and self-indicating scavenger resins. Investigations were carried out on the scope of known reactions on the 3- position of guaiazulene for this purpose..

Novel perspectives for the application of total internal reflection microscopy

Total Internal Reflection Microscopy (TIRM) is a sensitive non-invasive technique to measure the interaction potentials between a colloidal particle and a wall with femtonewton resolution. The equilibrium distribution of the particle-wall separation distance z is sampled monitoring the intensity I scattered by the Brownian particle under evanescent illumination. Central to the data analysis is the knowledge of the relation between I and the corresponding z, which typically must be known a priori. This poses considerable constraints to the experimental conditions where TIRM can be applied (short penetration depth of the evanescent wave, transparent surfaces). Here, we introduce a method to experimentally determine I(z) by relying only on the distance-dependent particle-wall hydrodynamic interactions. We demonstrate that this method largely extends the range of conditions accessible with TIRM, and even allows measurements on highly reflecting gold surfaces where multiple reflections lead to a complex I(z).Comment: 11 pages, 7 figure