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Disaggregate wealth and aggregate consumption: An investigation of empirical relationships for the G7
To date, testing for wealth effects in consumption has mainly used aggregate wealth definitions,
and/or is on a single-country basis. This study breaks new ground by analysing disaggregated wealth in
consumption functions for G7 countries. Contrary to other empirical work, illiquid financial wealth, (securities,
pensions and mortgage debt), tends to be a more significant long-run determinant of consumption than liquid
financial wealth. We suggest that this pattern reflects a shift from liquidity constrained to life cycle behaviour
following financial liberalisation. Results were robust in SURE analysis, tested in a nested manner, using
varying definition of liquid assets and using non-property income instead of personal disposable income. Wald
tests indicate similar long-run behaviour for all EU countries including the UK
Panel estimation of the impact of exchange rate uncertainty on investment in the major industrial countries
We estimate the impact of exchange rate uncertainty on investment, using panel estimation
featuring a decomposition of exchange rate volatility derived from the components
GARCH model of Engle and Lee (1999). For a poolable subsample of EU countries, it is
the transitory and not the permanent component of volatility which adversely affects
investment, implying high frequency shocks of the type that may be generated by volatile
short term capital flows are most deleterious for investment. Results based on EGARCH
also suggest that the response of investment to exchange rate uncertainty may depend
partly on the sign of the initial shock. (100 words
Beyond A/B Testing: Sequential Randomization for Developing Interventions in Scaled Digital Learning Environments
Randomized experiments ensure robust causal inference that are critical to
effective learning analytics research and practice. However, traditional
randomized experiments, like A/B tests, are limiting in large scale digital
learning environments. While traditional experiments can accurately compare two
treatment options, they are less able to inform how to adapt interventions to
continually meet learners' diverse needs. In this work, we introduce a trial
design for developing adaptive interventions in scaled digital learning
environments -- the sequential randomized trial (SRT). With the goal of
improving learner experience and developing interventions that benefit all
learners at all times, SRTs inform how to sequence, time, and personalize
interventions. In this paper, we provide an overview of SRTs, and we illustrate
the advantages they hold compared to traditional experiments. We describe a
novel SRT run in a large scale data science MOOC. The trial results
contextualize how learner engagement can be addressed through inclusive
culturally targeted reminder emails. We also provide practical advice for
researchers who aim to run their own SRTs to develop adaptive interventions in
scaled digital learning environments
Informal care and home-based palliative care: The health-related quality of life of carers
Health is an important factor in the capacity of family and friends (informal carers) to continue providing care for palliative care patients at home. This study investigates associations between the health-related quality of life (HRQOL) of current informal carers and characteristics of the carers and their caregiving situation, in a sample of Australian carers of palliative care patients. The cross-sectional study used the Short Form-36 Health Survey to measure HRQOL. It found carers to have better physical health and worse mental health than the general population. Of 178 carers, 35% reported their health to be worse than it was one year ago. Multiple regression analyses found that the HRQOL of carers whose health had deteriorated in the previous year was associated with the patient's care needs but not the carer's time input, unlike the carers reporting stable health. Clinicians caring for palliative care patients should be alert to the potential health impairments of informal carers and ensure that they are adequately supported in their caregiving role and have access to appropriate treatment and preventive health care. Β© 2010 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc
architect: Arbitrary-precision Constant-hardware Iterative Compute
Many algorithms feature an iterative loop that converges to the result of interest. The numerical operations in such algorithms are generally implemented using finite-precision arithmetic, either fixed or floating point, most of which operate least-significant digit first. This results in a fundamental problem: if, after some time, the result has not converged, is this because we have not run the algorithm for enough iterations or because the arithmetic in some iterations was insufficiently precise? There is no easy way to answer this question, so users will often over-budget precision in the hope that the answer will always be to run for a few more iterations. We propose a fundamentally new approach: armed with the appropriate arithmetic able to generate results from most-significant digit first, we show that fixed compute-area hardware can be used to calculate an arbitrary number of algorithmic iterations to arbitrary precision, with both precision and iteration index increasing in lockstep. Thus, datapaths constructed following our principles demonstrate efficiency over their traditional arithmetic equivalents where the latterβs precisions are either under- or over-budgeted for the computation of a result to a particular accuracy. For the execution of 100 iterations of the Jacobi method, we obtain a 1.60x increase in frequency and 15.7x LUT and 50.2x flip-flop reductions over a 2048-bit parallel-in, serial-out traditional arithmetic equivalent, along with 46.2x LUT and 83.3x flip-flop decreases versus the state-of-the-art online arithmetic implementation
Holographic Metamagnetism, Quantum Criticality, and Crossover Behavior
Using high-precision numerical analysis, we show that 3+1 dimensional gauge
theories holographically dual to 4+1 dimensional Einstein-Maxwell-Chern-Simons
theory undergo a quantum phase transition in the presence of a finite charge
density and magnetic field. The quantum critical theory has dynamical scaling
exponent z=3, and is reached by tuning a relevant operator of scaling dimension
2. For magnetic field B above the critical value B_c, the system behaves as a
Fermi liquid. As the magnetic field approaches B_c from the high field side,
the specific heat coefficient diverges as 1/(B-B_c), and non-Fermi liquid
behavior sets in. For B<B_c the entropy density s becomes non-vanishing at zero
temperature, and scales according to s \sim \sqrt{B_c - B}. At B=B_c, and for
small non-zero temperature T, a new scaling law sets in for which s\sim
T^{1/3}. Throughout a small region surrounding the quantum critical point, the
ratio s/T^{1/3} is given by a universal scaling function which depends only on
the ratio (B-B_c)/T^{2/3}.
The quantum phase transition involves non-analytic behavior of the specific
heat and magnetization but no change of symmetry. Above the critical field, our
numerical results are consistent with those predicted by the Hertz/Millis
theory applied to metamagnetic quantum phase transitions, which also describe
non-analytic changes in magnetization without change of symmetry. Such
transitions have been the subject of much experimental investigation recently,
especially in the compound Sr_3 Ru_2 O_7, and we comment on the connections.Comment: 23 pages, 8 figures v2: added ref
Recombinant expression of Streptococcus pneumoniae capsular polysaccharides in Escherichia coli.
Currently, Streptococcus pneumoniae is responsible for over 14 million cases of pneumonia worldwide annually, and over 1 million deaths, the majority of them children. The major determinant for pathogenesis is a polysaccharide capsule that is variable and is used to distinguish strains based on their serotype. The capsule forms the basis of the pneumococcal polysaccharide vaccine (PPV23) that contains purified capsular polysaccharide from 23 serotypes, and the pneumococcal conjugate vaccine (PCV13), containing 13 common serotypes conjugated to CRM197 (mutant diphtheria toxin). Purified capsule from S. pneumoniae is required for pneumococcal conjugate vaccine production, and costs can be prohibitively high, limiting accessibility of the vaccine in low-income countries. In this study, we demonstrate the recombinant expression of the capsule-encoding locus from four different serotypes of S. pneumoniae within Escherichia coli. Furthermore, we attempt to identify the minimum set of genes necessary to reliably and efficiently express these capsules heterologously. These E. coli strains could be used to produce a supply of S. pneumoniae serotype-specific capsules without the need to culture pathogenic bacteria. Additionally, these strains could be applied to synthetic glycobiological applications: recombinant vaccine production using E. coli outer membrane vesicles or coupling to proteins using protein glycan coupling technology
An extracellular steric seeding mechanism for Eph-ephrin signaling platform assembly
Erythropoetin-producing hepatoma (Eph) receptors are cell-surface protein tyrosine kinases mediating cell-cell communication. Upon activation, they form signaling clusters. We report crystal structures of the full ectodomain of human EphA2 (eEphA2) both alone and in complex with the receptor-binding domain of the ligand ephrinA5 (ephrinA5 RBD). Unliganded eEphA2 forms linear arrays of staggered parallel receptors involving two patches of residues conserved across A-class Ephs. eEphA2-ephrinA5 RBD forms a more elaborate assembly, whose interfaces include the same conserved regions on eEphA2, but rearranged to accommodate ephrinA5 RBD. Cell-surface expression of mutant EphA2s showed that these interfaces are critical for localization at cell-cell contacts and activation-dependent degradation. Our results suggest a 'nucleation' mechanism whereby a limited number of ligand-receptor interactions 'seed' an arrangement of receptors which can propagate into extended signaling arrays
MYOD-1 in normal colonic mucosa : role as a putative biomarker?
Background
DNA methylation of promoter-associated CpG islands of certain genes may play a role in the development of colorectal cancer. The MYOD-1 gene which is a muscle differentiation gene has been showed to be significantly methylated in colorectal cancer which, is an age related event. However the role of this gene in the colonic mucosa is not understood and whether methylation occurs in subjects without colon cancer. In this study, we have determined the frequency of methylation of the MYOD-1 gene in normal colonic mucosa and investigated to see if this is associated with established colorectal cancer risk factors primarily ageing.
Results
We analysed colonic mucosal biopsies in 218 normal individuals and demonstrated that in most individuals promoter hypermethylation was not quantified for MYOD-1. However, promoter hypermethylation increased significantly with age (pβ<β0.001 using regression analysis) and this was gender independent. We also showed that gene promoter methylation increased positively with an increase in waist to hip (WHR) ratio β the latter is also a known risk factor for colon cancer development.
Conclusions
Our study suggests that promoter gene hypermethylation of the MYOD-1 gene increases significantly with age in normal individuals and thus may offer potential as a putative biomarker for colorectal cancer
Formal Methods in Industrial Practice:Bridging the Gap (Track Summary)
Already for many decades, formal methods are considered to be the way forward to help the software industry to make more reliable and trustworthy software. However, despite this strong belief, and many individual success stories, no real change in industrial software development seems to happen. In fact, the software industry is moving fast forward itself, and the gap between what formal methods can achieve, and the daily software development practice does not seem to get smaller (and might even be growing)
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