MP3 - A meteorology and physical properties package to explore air-sea interaction on Titan

The exchange of mass, heat and momentum at the air:sea interface are profound influences on the terrestrial environment, affecting the intensity of hurricanes, the size of waves and lake-effect precipitation. Titan presents us with an opportunity to study these processes in a novel physical context, with a different sea, atmosphere and gravity. The MP3 instrument, under development for the proposed Discovery mission TiME (Titan Mare Explorer [1,2]) is an integrated suite of small, simple sensors that combines the function of traditional meteorology packages with liquid physical properties and depth-sounding : these latter functions follow the concept of - and indeed use spare elements from - the Huygens Surface Science Package (SSP,[3]). However, unlike Huygens’ brief and dynamic 3 hours of measurement, in TiME’s 6-Titan-day (96 Earth day) nominal mission enabled by radioisotope power, MP3 will have an unprecedented long-term measurement opportunity in one of the most evocative environments in the solar system, Titan’s sea Ligeia Mare

B decay and the Upsilon mass

Theoretical predictions for inclusive semileptonic B decay rates are rewritten in terms of the Upsilon(1S) meson mass instead of the b quark mass, using a modified perturbation expansion. This method gives theoretically consistent and phenomenologically useful results. Perturbation theory is well behaved, and the largest theoretical error in the predictions coming from the uncertainty in the quark mass is eliminated. The results are applied to the determination of $|V_{cb}|$, $|V_{ub}|$, and $\lambda_1$.Comment: 8 pages revte

On the Solvation of Redox Mediators and Implications for their Reactivity in Li-Air Batteries

Lithium-air batteries are a promising energy storage technology for transport applications, given their exceptionally high energy density. However, their development is significantly hampered by high overpotentials, which lead to poor efficiency and short lifetimes. Redox mediators provide a solution to this problem by shuttling electrons from the electrode to the active species at just above the redox potential of the mediator. Thus, knowing the redox potential and having the ability to tune it are critical to electrochemical performance. We focus on LiI as a model mediator—given its additional role in controlling LiOH vs Li2O2 chemistry—and use cyclic voltammetry (CV), NMR, UV/Vis spectrometry, and molecular dynamics (MD) simulations to monitor the effects of electrolyte composition on solvation. Li+ and I– solvation in common Li-air solvents, the electrochemical implications, and the applicability of each technique to probe the nature of the solvation shell and its effect on the electrochemical properties are explored. Starting with a simple thermodynamic model, we then used UV/Vis spectrometry to probe I– solvation, 1H NMR spectroscopy to study water solvation and 31P of the probe molecule triethylphosphine oxide (TEPO) to explore Li+ solvation; we find that no single descriptor can provide an accurate description of the solvation environment. Instead, we use all these methods in combination with the MD results to help rationalise the CV data. We find that the I– solvation improves significantly in tetraglyme (G4), with increasing salt and water concentration, but minimal effects on changing salt/water concentrations are seen in DMSO. In contrast, increasing salt concentration increases the Li+ activity in DMSO but not in G4. Furthermore, a simple model considering the equilibria between the different species was used to explain the 1H NMR data.</jats:p

The three species monomer-monomer model: A mean-field analysis and Monte Carlo study

We study the phase diagram and critical behavior of a one dimensional three species monomer-monomer surface reaction model. Static Monte Carlo simulations show a phase diagram consisting of a reactive steady state bordered by three equivalent unreactive phases where the surface is saturated with one monomer species. The transitions from the reactive to saturated phases are all continuous, while the transitions between poisoned phases are first-order, with bicritical points where the reactive phase meets two poisoned phases. A mean-field cluster analysis predicts all of the qualitative features of the phase diagram only when correlations up to triplets of adjacent sites are included. Dynamic Monte Carlo simulations show that the transition from the reactive to a saturated phase show critical behavior in the directed percolation universality class, while the bicritical point shows critical behavior in the even branching annihilating random walk class. The crossover from bicritical to critical behavior is also studied.Comment: 16 pages using RevTeX, plus 10 figures. Uses psfig.st

On the Solvation of Redox Mediators and Implications for their Reactivity in Li-Air Batteries

Lithium-air batteries are a promising energy storage technology for transport applications, given their exceptionally high energy density. However, their development is significantly hampered by high overpotentials, which lead to poor efficiency and short lifetimes. Redox mediators provide a solution to this problem by shuttling electrons from the electrode to the active species at just above the redox potential of the mediator. Thus, knowing the redox potential and having the ability to tune it are critical to electrochemical performance. We focus on LiI as a model mediator—given its additional role in controlling LiOH vs Li2O2 chemistry—and use cyclic voltammetry (CV), NMR, UV/Vis spectrometry, and molecular dynamics (MD) simulations to monitor the effects of electrolyte composition on solvation. Li+ and I– solvation in common Li-air solvents, the electrochemical implications, and the applicability of each technique to probe the nature of the solvation shell and its effect on the electrochemical properties are explored. Starting with a simple thermodynamic model, we then used UV/Vis spectrometry to probe I– solvation, 1H NMR spectroscopy to study water solvation and 31P of the probe molecule triethylphosphine oxide (TEPO) to explore Li+ solvation; we find that no single descriptor can provide an accurate description of the solvation environment. Instead, we use all these methods in combination with the MD results to help rationalise the CV data. We find that the I– solvation improves significantly in tetraglyme (G4), with increasing salt and water concentration, but minimal effects on changing salt/water concentrations are seen in DMSO. In contrast, increasing salt concentration increases the Li+ activity in DMSO but not in G4. Furthermore, a simple model considering the equilibria between the different species was used to explain the 1H NMR data.</jats:p

Developing an intervention to facilitate family communication about inherited genetic conditions, and training genetic counsellors in its delivery.

Many families experience difficulty in talking about an inherited genetic condition that affects one or more of them. There have now been a number of studies identifying the issues in detail, however few have developed interventions to assist families. The SPRinG collaborative have used the UK Medical Research Council's guidance on Developing and Evaluating Complex Interventions, to work with families and genetic counsellors (GCs) to co-design a psycho-educational intervention to facilitate family communication and promote better coping and adaptation to living with an inherited genetic condition for parents and their children (<18 years). The intervention is modelled on multi-family discussion groups (MFDGs) used in psychiatric settings. The MFDG was developed and tested over three phases. First focus groups with parents, young people, children and health professionals discussed whether MFDG was acceptable and proposed a suitable design. Using evidence and focus group data, the intervention and a training manual were developed and three GCs were trained in its delivery. Finally, a prototype MFDG was led by a family therapist and co-facilitated by the three GCs. Data analysis showed that families attending the focus groups and intervention thought MFDG highly beneficial, and the pilot sessions had a significant impact on their family' functioning. We also demonstrated that it is possible to train GCs to deliver the MFDG intervention. Further studies are now required to test the feasibility of undertaking a definitive randomised controlled trial to evaluate its effectiveness in improving family outcomes before implementing into genetic counselling practice.The National Institute of Health Research funded the study but any views expressed do not necessarily reflect those of the Authority. Funded by NIHR reference number: RP-DG-1211-10015

Crystal chemistry of type paulkerrite and establishment of the paulkerrite group nomenclature

A single-crystal structure determination and refinement has been conducted for the type specimen of paulkerrite. The structure analysis showed that the mineral has monoclinic symmetry, space group P21/c, not orthorhombic, Pbca, as originally reported. The unit-cell parameters are a=10.569(2), b=20.590(4), c=12.413(2) Å, and β=90.33(3)∘. The results from the structure refinement were combined with electron microprobe analyses to establish the empirical structural formula A1[(H2O)0.98K0.02]Σ1.00 A2K1.00 M1(Mg1.02Mn0.982+)Σ2.00 M2(Fe1.203+Ti0.544+Al0.24Mg0.02)Σ2.00 M3(Ti0.744+ Fe0.263+)Σ1.00 (PO4)4.02 X[O1.21F0.47(OH)0.32]Σ2.00(H2O)10 ⋅ 3.95H2O, which leads to the end-member formula (H2O)KMg2Fe2Ti(PO4)4(OF)(H2O)10 ⋅ 4H2O. A proposal for a paulkerrite group, comprising orthorhombic members benyacarite, mantiennéite, pleysteinite, and hochleitnerite and monoclinic members paulkerrite and rewitzerite, has been approved by the International Mineralogical Association's Commission for New Minerals, Nomenclature and Classification. The general formulae are A2M12M22M3(PO4)4X2(H2O)10 ⋅ 4H2O and A1A2M12M22M3(PO4)4X2(H2O)10 ⋅ 4H2O for orthorhombic and monoclinic species, respectively, where A= K, H2O, □ (= vacancy); M1 = Mn2+, Mg, Fe2+, Zn (rarely Fe3+); M2 and M3 = Fe3+, Al, Ti4+ (and very rarely Mg); X= O, OH, F. In monoclinic species, K and H2O show an ordering at the A1 and A2 sites, whereas O, (OH), and F show a disordering over the two non-equivalent X1 and X2 sites, which were hence merged as X2 in the general formula. In both monoclinic and orthorhombic species, a high degree of mixing of Fe3+, Al, and Ti occurs at the M2 and M3 sites of paulkerrite group members, making it difficult to get unambiguous end-member formulae from the structural determination of the constituents at individual sites. To deal with this problem an approach has been used that involves merging the compositions at the M2 and M3 sites and applying the site-total-charge method. The merged-site approach allows end-member formulae to be obtained directly from the chemical analysis without the need to conduct crystal-structure refinements to obtain the individual site species.</p

The institutional shaping of management: in the tracks of English individualism

Globalisation raises important questions about the shaping of economic action by cultural factors. This article explores the formation of what is seen by some as a prime influence on the formation of British management: individualism. Drawing on a range of historical sources, it argues for a comparative approach. In this case, the primary comparison drawn is between England and Scotland. The contention is that there is a systemic approach to authority in Scotland that can be contrasted to a personal approach in England. An examination of the careers of a number of Scottish pioneers of management suggests the roots of this systemic approach in practices of church governance. Ultimately this systemic approach was to take a secondary role to the personal approach engendered by institutions like the universities of Oxford and Cambridge, but it found more success in the different institutional context of the USA. The complexities of dealing with historical evidence are stressed, as is the value of taking a comparative approach. In this case this indicates a need to take religious practice as seriously as religious belief as a source of transferable practice. The article suggests that management should not be seen as a simple response to economic imperatives, but as shaped by the social and cultural context from which it emerges