Resolution of an ancient surface science anomaly: Work function change induced by N adsorption on W{100}

For many decades it has been assumed that an adsorbate centered above a metal surface and with a net negative charge should increase the work function of the surface. However, despite their electronegativity, N adatoms on W{100} cause a significant work function decrease. Here we present a resolution of this anomaly. Using density functional theory, we demonstrate that while the N atom carries a negative charge, of overriding importance is a reduction in the surface overspill electron density into the vacuum, when that charge is engaged in bonding to the adatom. This novel interpretation is fundamentally important in the general understanding of work function changes induced by atomic adsorbates.

COMMUNICATION AND GREEK ENVIRONMENTAL ORGANISATIONS: MEANS OF COMMUNICATION AND INFLUENCING FACTORS

A basic operational objective of any environmental organisation is to raise awareness among the public on issues of environmental protection, through the dissemination of knowledge and experience to local communities, so that the conservation and ecologically sound management of natural resources can acquire a local dimension. This can be achieved either through interventions directed at the State, mainly in relation to its legislative function, or by encouraging citizens to change or improve their attitude regarding environmental matters. In order to ensure a successful outcome and the efficient functioning of any organisation, a feeling of mutual trust and understanding should exist between the latter and its various audiences, i.e. the State and society. A basic ingredient of this balance between the organisation, the broader public and the State is effective communication and activity planning. As a way of contributing to the exploration of this process, this paper describes the means of communication used by Greek environmental organisations, and presents, through a non-linear model, the differentiation amongst them, in conjunction with aspects of the profile of those running each organisation and other indicators, such as the years in operation and the membership figures in each sampled organisation. The paper concludes by arguing that the diversification of communication means is related to the head person's years as a member of the organisation and the extent of its total membership. Another important finding is that the more the involvement in activities within the organisation, the less differentiation we observe amongst the employed means of communication.

The historical geography of ancient Sicily: implications for genetics.

Malone, C.A.T. and S.K.F. Stoddart, . (co-authored).

Four independent gene phylogenies confirm the ancient relationships of Madagascar endemic species in the Papilio demoleus group (Lepidoptera, Papilionidae).

Madagascar is home to numerous endemic species and lineages, but the processes that have contributed to its endangered diversity are still poorly understood. Evidence is accumulating to demonstrate the importance of Tertiary dispersal across varying distances of oceanic barriers, supplementing vicariance relationships dating back to the Cretaceous, but these hypotheses remain tentative in the absence of well-supported phylogenies. In the Papilio demoleus group of swallowtail butterflies, three of the five recognized species are restricted to Madagascar, whereas the remaining two species range across the Afrotropical zone and southern Asia plus Australia. We reconstructed phylogenetic relationships for all species in the P. demoleus group, as well as 11 outgroup Papilio species, using 60 morphological characters and about 4 kb of nucleotide sequences from two mitochondrial (cytochrome oxidase I and II) and two nuclear (wg and EF-1a) genes. Of the three endemic Malagasy species, the two that are formally listed as endangered or at risk represented the most basal divergences in the group, while the more common third endemic was clearly related to African P. demodocus. The fifth species, P. demoleus, showed little differentiation across southern Asia, but showed divergence from its subspecies sthenelus in Australia. Dispersal-vicariance analysis using cladograms derived from morphology and three independent genes indicated a Malagasy diversification of lime swallowtails in the middle Miocene. Thus, diversification processes on the island of Madagascar may have contributed to the origin of common butterflies that now occur throughout much of the Old World tropical and subtemperate regions. An alternative hypothesis, that Madagascar is a refuge for ancient lineages resulting from successive colonizations from Africa, is less parsimonious and does not explain the relatively low continental diversity of the group.

Commonality in Returns, Order Flows, and Liquidity in the Greek Stock Market

Using a unique high-frequency data-set on a comprehensive sample of Greek blue-chip stocks, spanning from September 2003 through March 2006, this note assesses the extent and role of commonality in returns, order flows (OFs), and liquidity. It also formally models aggregate equity returns in terms of aggregate equity OF, in an effort to clarify OF's importance in explaining returns for the Athens Exchange market. Almost a quarter of the daily returns in the FTSE/ATHEX20 index is explained by aggregate own OF. In a second step, using principal components and canonical correlation analyses, we document substantial common movements in returns, OFs, and liquidity, both on a market-wide basis and on an individual security basis. These results emphasize that asset pricing and liquidity cannot be analyzed in isolation from each other.