Preservation of York Minster historic limestone by hydrophobic surface coatings

Magnesian limestone is a key construction component of many historic buildings that is under constant attack from environmental pollutants notably by oxides of sulfur via acid rain, particulate matter sulfate and gaseous SO 2 emissions. Hydrophobic surface coatings offer a potential route to protect existing stonework in cultural heritage sites, however, many available coatings act by blocking the stone microstructure, preventing it from 'breathing' and promoting mould growth and salt efflorescence. Here we report on a conformal surface modification method using self-assembled monolayers of naturally sourced free fatty acids combined with sub-monolayer fluorinated alkyl silanes to generate hydrophobic (HP) and super hydrophobic (SHP) coatings on calcite. We demonstrate the efficacy of these HP and SHP surface coatings for increasing limestone resistance to sulfation, and thus retarding gypsum formation under SO/H O and model acid rain environments. SHP treatment of 19th century stone from York Minster suppresses sulfuric acid permeation.

An exploration of the effect of super large n-tuples on single layer RAMnets

N-tuple recognition systems (RAMnets) are normally modeled using a small number of input lines to each RAM, because the address space grows exponentially with the number of inputs. It is impossible to implement an arbitrarily-large address space as physical memory. But given modest amounts of training data, correspondingly modest numbers of bits will be set in that memory. Hash arrays can therefore be used instead of a direct implementation of the required address space. This paper describes some exploratory experiments using the hash array technique to investigate the performance of RAMnets with very large numbers of input lines. An argument is presented which concludes that performance should peak at a relatively small n-tuple size, but the experiments carried out so far contradict this. Further experiments are needed to confirm this unexpected result.

Between Moscow and London. Romanian Orthodoxy and National Communism, 1960-1965

This article analyses the convoluted path of the Romanian communist regime's rapprochement with the West in the early 1960s. While, officially, the church supported the regime, the hierarchs strengthened their contacts with the West. This article argues that, paradoxically, church participation in international religious dialogue represented direct support for the nationalist stance of Romanian Communism. The increased number of ecumenical relations between Romania and the West reached its climax with the visit of Michael Ramsey, the Archbishop of Canterbury, to Romania in 1965, a few months before the country became the Socialist Republic of Romania.

Unity in Christ or Pan-Europeanism?:Nathan Söderblom and the ecumenical peace movement in the interwar period

In the summer of 2014 the Swedish Church is celebrating the 100th anniversary of the appointment of Nathan Söderblom as archbishop of Uppsala, and thus head of the Swedish church organisation. As a Lutheran with an enormously broad-minded and broad-reaching approach to ecumenical understanding and community-building, Söderblom shot to prominence in the interwar period not only because of his ecumenical engagement, calling for an evangelical catholicity so stand side by side with the Roman catholic and Orthodox catholic traditions, but also because of his comprehensive secular engagement for peace and understanding between peoples. In the latter context he also acquired a solid reputation as a perhaps less prominent but still noteworthy figure in the history of European integration. This article investigates how, why and to what extent Söderblom’s ecumenical and secular engagements were intertwined. The first part discusses how his biographical and academic background led to such staunch ecumenical positions, while the second part focuses on the secular engagement, which was perceived by Söderblom as necessary to make progress on the ecumenical front in the practical political realities of the 1920s. The final part, comparing and contrasting Söderblom’s views with those of Count Richard von Coudenhove-Calergi and the Pan-European Union, demonstrates why Söderblom’s engagement for Europe had to be limited: unity in Christ is by definition global in nature and therefore cannot be continent-specific.