Interplay between the ionic and electronic density profiles in liquid metal surfaces

First principles molecular dynamics simulations have been performed for the liquid-vapor interfaces of liquid Li, Mg, Al and Si. We analize the oscillatory ionic and valence electronic density profiles obtained, their wavelengths and the mechanisms behind their relative phase-shift.Comment: Accepted for publication in Journal of Chemical Physic

Orbital-Free Molecular Dynamics Simulations of Melting in Na8 and Na20: Melting in Steps

The melting-like transitions of Na8 and Na20 are investigated by ab initio constant energy molecular dynamics simulations, using a variant of the Car-Parrinello method which employs an explicit electronic kinetic energy functional of the density, thus avoiding the use of one-particle orbitals. Several melting indicators are evaluated in order to determine the nature of the various transitions, and compared with other simulations. Both Na8 and Na20 melt over a wide temperature range. For Na8, a transition is observed to begin at approx. 110 K, between a rigid phase and a phase involving isomerizations between the different permutational isomers of the ground state structure. The ``liquid'' phase is completely established at approx. 220 K. For Na20, two transitions are observed: the first, at approx. 110 K, is associated with isomerization transitions between those permutational isomers of the ground state structure which are obtained by interchanging the positions of the surface-like atoms; the second, at approx. 160 K, involves a structural transition from the ground state isomer to a new set of isomers with the surface molten. The cluster is completely ``liquid'' at approx. 220 K.Comment: Revised version, accepted for publication in J. Chem. Phys. The changes include longer simulations for the Na20 microcluster, a more complete comparison to previous theoretical results, and the discussion of some technical details of the method applie

Childhood reading problems and cognitive ageing across mid to later life

BACKGROUND: Little research has investigated long-term associations of childhood reading with cognitive ageing. The aim of this study was to test longitudinal associations between childhood reading problems and cognitive function from mid-adulthood (age 43) to early old age (age 69), and whether associations were mediated by education. METHODS: Data were from the MRC National Survey of Health and Development, a prospective population-based birth cohort. Reading problems were measured at age 11 using a reading test. Verbal memory and processing speed were measured at ages 43, 53, 60-64 and 69 and Addenbrooke's Cognitive Examination (ACE) was administered at age 69. Linear mixed models and path analyses were used to test: (1) associations between reading problems and verbal memory and processing speed trajectories; (2) associations between reading problems and ACE-III scores; (3) whether associations were mediated by education. RESULTS: Reading problems were associated with poorer verbal memory at intercept but not rate of decline (N=1726), and were not associated with processing speed intercept or decline (N=1730). There were higher rates of scores below ACE-III clinical thresholds (<82 and <88) in people with reading problems compared with those without. Reading problems were associated with poorer total ACE-III scores and all domain scores at age 69 (N=1699). Associations were partly mediated by education. CONCLUSION: Reading problems in childhood were associated with poorer cognitive function in early old age, and associations were partly mediated by education

An Algorithmic Framework for Labeling Network Maps

Drawing network maps automatically comprises two challenging steps, namely laying out the map and placing non-overlapping labels. In this paper we tackle the problem of labeling an already existing network map considering the application of metro maps. We present a flexible and versatile labeling model. Despite its simplicity, we prove that it is NP-complete to label a single line of the network. For a restricted variant of that model, we then introduce an efficient algorithm that optimally labels a single line with respect to a given weighting function. Based on that algorithm, we present a general and sophisticated workflow for multiple metro lines, which is experimentally evaluated on real-world metro maps.Comment: Full version of COCOON 2015 pape

Allosteric p97 inhibitors can overcome resistance to ATP-competitive p97 inhibitors for potential anti-cancer therapy

A major challenge of targeted cancer therapy is the selection for drug‐resistant mutations in tumor cells leading to loss of treatment effectiveness. p97/VCP is a central regulator of protein homeostasis and a promising anti‐cancer target because of its vital role in cell growth and survival. One ATP‐competitive p97 inhibitor, CB‐5083, has entered clinical trials. Selective pressure on HCT116 cells treated with CB‐5083 identified 5 different resistant mutants. Identification of p97 inhibitors with different mechanisms of action would offer the potential to overcome this class of resistance mutations. Our results demonstrate that two CB‐5083 resistant p97 mutants, N660K and T688A, were also resistant to several other ATP‐competitive p97 inhibitors, whereas inhibition by two allosteric p97 inhibitors NMS‐873 and UPCDC‐30245 were unaffected by these mutations. We also established a CB‐5083 resistant cell line that harbors a new p97 double mutation (D649A/T688A). While CB‐5083, NMS‐873, and UPCDC‐30245 all effectively inhibited proliferation of the parental HCT116 cell line, NMS‐873 and UPCDC‐30245 were 30‐fold more potent than CB‐5083 in inhibiting the CB‐5083 resistant D649A/T688A double mutant. Our results suggest that allosteric p97 inhibitors are promising alternatives when resistance to ATP‐competitive p97 inhibitors arises during anti‐cancer treatment

The school-to-work transition, skill preferences and matching

This empirical paper investigates skill formation in the youth labour market. Using event-history data collected from the administrative records of Lancashire Careers Service, we model skill preferences formed at school by young people and skill destination, ie the occupation of the first job/training scheme after leaving compulsory schooling. We also model the duration of the individuals first unemployment spell. Competing risks models with flexible piece-wise linear baseline hazards and unobserved heterogeneity are estimated. There is evidence of occupational segregation by gender, unrealistic occupational preferences and excess supply of skills. Outcomes are mainly determined by examination performance, ethnicity and whether disadvantaged.