The great moderation under the microscope: decomposition of macroeconomic cycles in US and UK aggregate demand

In this paper the relationship between the growth of real GDP components is explored in the frequency domain using both static and dynamic wavelet analysis. This analysis is carried out separately for the US and UK using quarterly data, and the results are found to be substantially different for the two countries. One of the key findings of this research is that the ‘great moderation’ shows up only at certain frequencies, and not in all components of real GDP. We use these results to explain why the incidence of the great moderation has been so patchy across GDP components, countries and time periods. This also explains why it has been so hard to detect periods of moderation (or other periods) reliably in the aggregate data. We argue this cannot be done without separating the GDP components into their frequency components over time. Our results show why: the predictions of traditional real business cycle theory often appear not to be upheld in the data.business cycles; growth cycles; discrete wavelet analysis; US real GDP; UK real GDP

Time Evolution and Deterministic Optimisation of Correlator Product States

We study a restricted class of correlator product states (CPS) for a spin-half chain in which each spin is contained in just two overlapping plaquettes. This class is also a restriction upon matrix product states (MPS) with local dimension $2^n$ ($n$ being the size of the overlapping regions of plaquettes) equal to the bond dimension. We investigate the trade-off between gains in efficiency due to this restriction against losses in fidelity. The time-dependent variational principle formulated for these states is numerically very stable. Moreover, it shows significant gains in efficiency compared to the naively related matrix product states - the evolution or optimisation scales as $2^{3n}$ for the correlator product states versus $2^{4n}$ for the unrestricted matrix product state. However, much of this advantage is offset by a significant reduction in fidelity. Correlator product states break the local Hilbert space symmetry by the explicit selection of a local basis. We investigate this dependence in detail and formulate the broad principles under which correlator product states may be a useful tool. In particular, we find that scaling with overlap/bond order may be more stable with correlator product states allowing a more efficient extraction of critical exponents - we present an example in which the use of correlator product states is several orders of magnitude quicker than matrix product states.Comment: 19 pages, 14 figure

Does your wireless LAN have criminal intent?

All of the literature relating to wireless network security has focused on the flaws, newer alternatives and suggestions for securing the network. There is much speculation and anecdotal statements in relation to what can happen if a breach occurs, but this is mostly from a computer security perspective, and mostly expressed in terms of potential for financial loss. This paper examines the potential legal ramifications of failing to properly secure a wireless network. Several scenarios are examined within based on usage of wireless on the various category of attack. Legal opinion, backed up with case law, is provided for each scenario. Several examples are given for unauthorised use, with other aspects having potential for prosecution. The conclusion is that no matter whether you are a home user of wireless, a small to medium business or a large enterprise, there a legal as well as financial reasons to properly secure your wireless network

Tackling child neglect: key developments in Wales

This paper on child neglect policy and practice issues in Wales comprises three elements. First we introduce the topic in the context of current family support services that seek to offer early intervention to tackle, inter alia, child neglect and other not unconnected harms and adversities in childhood. Secondly, we set out key findings from a Welsh Government commissioned study into developing a multi-partner strategy for reducing child neglect across Wales. Thirdly, we conclude with a summary of critical ingredients that are likely to configure the development of a national response to neglect in Wales. Together these elements provide a snapshot of recent progress made in service development and strategic planning

Pfaffian-like ground states for bosonic atoms and molecules in one-dimensional optical lattices

We study ground states and elementary excitations of a system of bosonic atoms and diatomic Feshbach molecules trapped in a one-dimensional optical lattice using exact diagonalization and variational Monte Carlo methods. We primarily study the case of an average filling of one boson per site. In agreement with bosonization theory, we show that the ground state of the system in the thermodynamic limit corresponds to the Pfaffian-like state when the system is tuned towards the superfluid-to-Mott insulator quantum phase transition. Our study clarifies the possibility of the creation of exotic Pfaffian-like states in realistic one-dimensional systems. We also present preliminary evidence that such states support non-Abelian anyonic excitations that have potential application for fault-tolerant topological quantum computation.Comment: 10 pages, 10 figures. Matching the version published Phys.Rev.

Highly-functionalised difluorinated cyclohexane polyols via the Diels–Alder reaction : regiochemical control via the phenylsulfonyl group

A difluorinated dienophile underwent cycloaddition reactions with a range of furans to afford cycloadducts whichcould be processed regio- and stereoselectively via episulfonium ions, generated by the reaction between their alkenyl groups and phenylsulfenyl chloride. The oxabicyclic products were oxidised to the phenylsulfonyl level and ring opened via E1CB or reductive desulfonative pathways to afford, ultimately, difluorinated cyclohexene or cyclohexane polyols

The State of the Art: Object Retrieval in Paintings using Discriminative Regions

The objective of this work is to recognize object categories (such as animals and vehicles) in paintings, whilst learning these categories from natural images. This is a challenging problem given the substantial differences between paintings and natural images, and variations in depiction of objects in paintings. We first demonstrate that classifiers trained on natural images of an object category have some success in retrieving paintings containing that category. We then draw upon recent work in mid-level discriminative patches to develop a novel method for re-ranking paintings based on their spatial consistency with natural images of an object category. This method combines both class based and instance based retrieval in a single framework. We quantitatively evaluate the method over a number of classes from the PASCAL VOC dataset, and demonstrate significant improvements in rankings of the retrieved paintings over a variety of object categories

Isolation of Human Antigen-Specific Antibodies from Memory B-Cells Nearly Two Years Post Vaccination

Isolation and production of therapeutic human monoclonal antibodies (mAbs) traditionally utilizes a handful of techniques including antibody engineering, phage display, hybridoma generation from transgenic mice or EBV immortalization of B-cells. Over the past decade a new approach has emerged that attempts to extract antigen-specific memory B-cells from the peripheral blood of individuals vaccinated or infected with the target. Initial attempts focused on culturing B-cells and inducing differentiation to plasmablasts for analysis of antibody-antigen specificity, but results were largely mixed due to difficult culture conditions and/or rarity of target cells. With advancing technology in cell sorting, single antigen-specific memory B-cells can be identified and sorted with fluorescently labeled antigens. This method has produced virus-specific mAbs from HIV-infected patients and tetanus-specific mAbs within weeks after Tdap immunization. Many other studies claim to have found antigen-specific mAbs months to years after immunization or clearance of an infection; however, these studies fail to provide direct evidence of antibody specificity by cloning and expressing the mAbs from B-cells. Here we report the efficient isolation of tetanus-specific mAbs from a subject Td-immunized almost two years prior to blood draw. Initially, the total B-cell population was isolated from peripheral blood mononuclear cells enriched by negative selection, then stained to identify tetanus-specific memory B-cells. These cells were individually sorted and PCR was performed to amplify heavy and light chain variable regions of the B-cell’s antibody mRNA. After sequencing, 15 of 42 samples produced both heavy and light chain antibody sequence and 11 mAbs were cloned and transiently expressed. ELISA analysis indicated 5 of the 11 mAbs bound the Hc protein fragment of tetanus toxin and 3 were specific for Hc. We plan to extend this initial success to additional targets and longer gaps between vaccination and B-cell isolation to identify functional therapeutic human antibodies