The ECB Monetary Policy and the Current Financial Crisis

Our paper presents estimates of Taylor type rules for the euro area using quarterly data for the period 2004(Q4) to 2008(Q3). Unlike other studies, we employ a real-time data set using the quarterly ECB staff projections on inflation and output growth. Estimated realtime rules are also compared with a more conventional specification whereby ex-post data are employed. Our results suggest that: (i) the ECB monetary policy strategy can be represented with a simple interest-rate rule; (ii) the ECB takes into account the quarterly ECB staff projections when deciding on its monetary policy stance; (iii) the accommodative behaviour of the ECB often cited in the literature is related to differences between real-time and ex-post data; and (iv) the estimated simple interest-rate rule continues to capture the ECB monetary policy strategy during the recent financial crisis. In light of the above, we can draw three important policy conclusions. First, the ECB has a stabilising role in the economy. Second, the ECB has become rather hawkish in its monetary policy decision making, responding more to projected changes in inflation than to projected changes in the output growth gap. Finally, the ECB’s response during the recent financial crisis of reducing its interest rate to 1.00% by the first half of 2009 and undertaking non-standard measures to provide support to the financial sector is shown to be equivalent to following a simple interest-rate rule based on its previous practices.Taylor type rules, ECB monetary policy, real-time data, financial crisis

Accelerated Calderón Preconditioning for Electromagnetic Scattering by Multiple Absorbing Dielectric Objects

We consider electromagnetic scattering by multiple absorbing dielectric objects using the PMCHWT boundary integral equation formulation. Galerkin discretisation of this formulation leads to ill-conditioned linear systems, and Calderón preconditioning, an operator-based approach, can be used to remedy this. To obtain a stable discretisation of the operator products that arise in this approach, the use of a dual mesh defined on a barycentrically refined grid needs to be considered, increasing memory consumption. Furthermore, to capture the oscillatory solution of the electromagnetic waves, the mesh needs to be refined with respect to frequency, making the simulation of high-frequency problems very expensive. This thesis presents two complementary approaches to minimising memory cost and computation time (for assembly and solution): modification of the preconditioning operator, and a bi-parametric implementation. The former aims to minimise the number of operators used in the preconditioner to reduce the additional matrix-vector products performed, and the memory cost, while still maintaining a sufficient preconditioning effect. The latter uses two distinct sets of parameters during assembly, to minimise assembly and solution time as well as memory. The operator is assembled with a more expensive set of parameters to obtain an accurate solution. The preconditioner, which is discretised using the expensive dual basis functions, is assembled with a cheaper set of parameters. The two approaches are explained in the context of a series of model problems, then applied to realistic ice crystal configurations found in cirrus clouds. They are shown to deliver a reduction of 99% in memory cost and at least 80% in computation time, for the highest frequency considered. The accelerated formulations have been used at the Met Office to create a new database of the scattering properties of atmospheric ice crystals for future numerical weather prediction. A brief description of that work is also presented in the thesis

St John Chrysostom’s doctrine of baptism

This thesis represents a general introductory investigation into St John Chrysostom’s doctrine of Baptism on the basis of his Baptismal Catechetical Orations and all other relevant texts from the vast corpus of his writings. It consists of three parts which deal with: i) the presuppositions and preparation for Baptism, ii) the baptismal liturgy and its meaning and iii) the general understanding of Baptism. The first part investigates the roles of the candidates for Baptism, their sponsors who accompany them and the priests who baptize them, and concentrates on the themes of repentance, good works, fasting and prayer, which are essential to the preparation of the candidates and the contents of the catechetical teaching which they receive. The second part goes through the baptismal liturgy step by step and as far as Chrysostom's texts bear witness to it and attempts to bring out the meaning of the various acts involved, especially those of exorcism, renunciation of Satan, uniting with Christ, chrismation and anointing, confession, baptism, the new garments, the Lord's prayer, the exchange of brotherly kiss and communion in the Body and Blood of Christ. The third part attempts to formulate a general understanding of Baptism by selecting four main themes, 1) the act of Baptism, as an act of divine adoption which is performed only once, 2) the connection between Baptism and Christ, understood on the one hand as participation in his crucifixion, death, burial and resurrection and, on the other hand, as a spiritual wedding, 3) the connection between Baptism and the Holy Spirit, expounded in terms of the Spirit as a gift to the believer and the believer's new life in the Spirit, and finally 4) the connection between Baptism and the believer, expounded in terms of regeneration, forgiveness of sins and purification, mortification of passions and rejuvenation and purity. What is particularly significant in the emerging conclusions which bring together the main points of the three parts of the dissertation is the free coordination of divine grace and human response, which are typical of the mind of the great catechist and pastor of the early Church, St John Chrysostom

Comprehensive characterization of an open source document search engine

This work performs a thorough characterization and analysis of the open source Lucene search library. The article describes in detail the architecture, functionality, and micro-architectural behavior of the search engine, and investigates prominent online document search research issues. In particular, we study how intra-server index partitioning affects the response time and throughput, explore the potential use of low power servers for document search, and examine the sources of performance degradation ands the causes of tail latencies. Some of our main conclusions are the following: (a) intra-server index partitioning can reduce tail latencies but with diminishing benefits as incoming query traffic increases, (b) low power servers given enough partitioning can provide same average and tail response times as conventional high performance servers, (c) index search is a CPU-intensive cache-friendly application, and (d) C-states are the main culprits for performance degradation in document search.Web of Science162art. no. 1

The development and evolution of transactive memory system over time in MUVEs

CSCW in education is a topic that drew a lot of attention over the years, and Multi User Virtual Environments (MUVEs) are one of the tools utilized by many educators to support their teaching objectives. MUVEs enable students to connect, immerse and interact with their peers and the environment, and synchronously engage and collaborate in learning activities. Effective communication and collaboration contributes to student learning, and the topic of Transactive Memory System (TMS) within working groups has been found to be very beneficial. TMS relates to the representation of the knowledge possessed by the members of a team that allows identifying who knows what, providing efficiency in collaboration. While the use of educational MUVEs has been thoroughly investigated in the literature, little is known about the use of such environments to support TMS and their relationship with working group dynamics. This paper presents the results of a study investigating the development and evolution of a TMS between groups within a MUVE, in order to better understand the dynamics that need to be considered when using MUVEs to support teaching and learning

Adaptive notifications to support knowledge sharing in virtual communities

Social web-groups where people with common interests and goals communicate, share resources, and construct knowledge, are becoming a major part of today’s organisational practice. Research has shown that appropriate support for effective knowledge sharing tailored to the needs of the community is paramount. This brings a new challenge to user modelling and adaptation, which requires new techniques for gaining sufficient understanding of a virtual community (VC) and identifying areas where the community may need support. The research presented here addresses this challenge presenting a novel computational approach for community-tailored support underpinned by organisational psychology and aimed at facilitating the functioning of the community as a whole (i.e. as an entity). A framework describing how key community processes—transactive memory (TM), shared mental models (SMMs), and cognitive centrality (CCen)—can be utilised to derive knowledge sharing patterns from community log data is described. The framework includes two parts: (i) extraction of a community model that represents the community based on the key processes identified and (ii) identification of knowledge sharing behaviour patterns that are used to generate adaptive notifications. Although the notifications target individual members, they aim to influence individuals’ behaviour in a way that can benefit the functioning of the community as a whole. A validation study has been performed to examine the effect of community-adapted notifications on individual members and on the community as a whole using a close-knit community of researchers sharing references. The study shows that notification messages can improve members’ awareness and perception of how they relate to other members in the community. Interesting observations have been made about the linking between the physical and the VC, and how this may influence members’ awareness and knowledge sharing behaviour. Broader implications for using log data to derive community models based on key community processes and generating community-adapted notifications are discussed

Crisis? consequences on recapitalization and exposure for Cypriot and Greek cooperative banks

The financial crisis of 2008 transformed, in some countries, to economic and social one, created serious problems to the banking system. Capital basis and asset exposures, especially through the non-performing loans, have been the most important. Capital inadequacy caused the failure of banks that didn?t succeed to accomplish the capital requirements set by Basel II obligations.The treatment was not the same for all banks as only those considered as significant banks, for the economy, received capital aid from their state. The paper investigates through capital basis requirements and asset exposures the crisis? consequences on Cyprus and Greek cooperative banks. The consequences were cataclysmic for the cooperative banking systems of the two countries. In Greece, the cooperative banks did not receive any state aid, leading to the bankruptcy of many of them. In Cyprus, once all the cooperative banks were merged into the central cooperative bank, the latter received state aid as it was considered as a significant bank for the national economy. Moreover, the high level of non-performing loans and the new economic environment that the crisis had caused, forced the cooperative banks to change their asset exposures structure and their credit policy

Identification of the catalytic motif of the microbial ribosome inactivating cytotoxin colicin E3

Colicin E3 is a cytotoxic ribonuclease that specifically cleaves 16S rRNA at the ribosomal A-site to abolish protein synthesis in sensitive Escherichia coli cells. We have performed extensive mutagenesis of the 96-residue colicin E3 cytotoxic domain (E3 rRNase), assayed mutant colicins for in vivo cytotoxicity, and tested the corresponding E3 rRNase domains for their ability to inactivate ribosome function in vitro. From 21 alanine mutants, we identified five positions where mutation resulted in a colicin with no measurable cytotoxicity (Y52, D55, H58, E62, and Y64) and four positions (R40, R42, E60, and R90) where mutation caused a significant reduction in cytotoxicity. Mutations that were found to have large in vivo and in vitro effects were tested for structural integrity through circular dichroism and fluorescence spectroscopy using purified rRNase domains. Our data indicate that H58 and E62 likely act as the acid–base pair during catalysis with other residues likely involved in transition state stabilization. Both the Y52 and Y64 mutants were found to be highly destabilized and this is the likely origin of the loss of their cytotoxicity. The identification of important active site residues and sequence alignments of known rRNase homologs has allowed us to identify other proteins containing the putative rRNase active site motif. Proteins that contained this active site motif included three hemagglutinin-type adhesins and we speculate that these have evolved to deliver a cytotoxic rRNase into eukaryotic cells during pathogenesis