The effect of respondent incentives on panel attrition in a sequential mixed-mode design

This paper evaluates the effect of switching an existing panel study from a unimode face-to-face design to a sequential mixed-mode design (web followed by face-to-face interviewing) on attrition. I use large-scale randomised experimental data from the Innovation Panel of Understanding Society. While the introduction of a mixed-mode design increases panel attrition one wave after the mode switch (IP6), the effect is eroded at subsequent waves (IP7-IP9). The offer of higher incentives to sample members in the mixed-mode group cancels the negative effect of mixed-mode on attrition one wave after the mode switch (IP6) and leads to higher response over time (IP7-IP9)

Focus - Eurozone labour market

Over the past two years, the Euro zone labour market has been in decline. Employment fell more steeply for the younger population cohort, for men rather than women and for workers on temporary contracts compared with other forms of contract. Also, the scenario appears to vary widely from one Euro zone country to another. A comparison of employment elasticity with pre- and mid-crisis GDP reveals that structural features and government policies have impacted on the performance of the labour market in Member States

Spain, a tough job

The rise in unemployment in Spain, well in excess of the European average, reflects the sharper cyclical correction in the economy but also the greater elasticity of employment to GDP, due to the marked duality of the Spanish labour market. The return to positive growth rates and the reforms implemented by the government in the last year should help employment recover as of 2012. However, some of the growth in unemployment might prove structural and have negative repercussions on domestic demand and the public finance balances. Thus, further progress on the reform front is crucial

Biochemical and spectroscopic properties of Brucella microti glutamate decarboxylase, a key component of the glutamate-dependent acid resistance system

In orally acquired bacteria, the ability to counteract extreme acid stress (pH < 2.5) ensures survival during transit through the animal host stomach. In several neutralophilic bacteria, the glutamate-dependent acid resistance system (GDAR) is the most efficient molecular system in conferring protection from acid stress. In Escherichia coli its structural components are either of the two glutamate decarboxylase isoforms (GadA, GadB) and the antiporter, GadC, which imports glutamate and exports γ-aminobutyrate, the decarboxylation product. The system works by consuming protons intracellularly, as part of the decarboxylation reaction, and exporting positive charges via the antiporter. Herein, biochemical and spectroscopic properties of GadB from Brucella microti (BmGadB), a Brucella species which possesses GDAR, are described. B. microti belongs to a group of lately described and atypical brucellae that possess functional gadB and gadC genes, unlike the most well-known "classical" Brucella species, which include important human pathogens. BmGadB is hexameric at acidic pH. The pH-dependent spectroscopic properties and activity profile, combined with in silico sequence comparison with E. coli GadB (EcGadB), suggest that BmGadB has the necessary structural requirements for the binding of activating chloride ions at acidic pH and for the closure of its active site at neutral pH. On the contrary, cellular localization analysis, corroborated by sequence inspection, suggests that BmGadB does not undergo membrane recruitment at acidic pH, which was observed in EcGadB. The comparison of GadB from evolutionary distant microorganisms suggests that for this enzyme to be functional in GDAR some structural features must be preserved

Ireland: two months that will decide the country’s fate

The shock revision to the 2010 deficit and debt estimates has raised serious concerns about the sustainability of Ireland’s public finances. If in the next four years the country neared the deficit targets agreed with the European Union, long-term sustainability would be a joke. The drafting by mid-November of a credible package of measures delivering a break-even primary balance in a few years, without triggering an economic depression, will be very complex. But it is a challenge Ireland can no longer avoid

Mixing modes and measurement methods in longitudinal studies

Across the world longitudinal studies are facing falling response rates, at the same time cost imperatives are bringing into question the feasibility of large scale regular face-to-face data collection. While, the rapid development of communications technology and associated cultural changes is assumed to mean that study participants will increasingly expect to be able to answer surveys when and how it suits them. All of these factors are driving longitudinal studies to combine different modes of data collection both to increase response and to reduce costs. Mixing modes of data collection either across individuals at one point in time or within individuals over time, presents longitudinal researchers with a range of methodological challenges in both data collection and analysis. Within CLOSER, and beyond, studies are investigating different aspects of the implications of mixed mode data collection, and giving data users varying degrees of support and advice about issues that should be of concern. Drawing on evidence from across CLOSER’s longitudinal studies, this report reviews the latest evidence gathered on the effect of mixing modes and measurement methods on response, measurement issues and survey costs. The review also focuses on the implications for analysis of measures collected in different ways either across individuals at the same point in time or within individuals over time. Building on these reviews, we identify what further research is required in relation to both the design and analysis of mixed mode data collection. The contents of this report is based on a CLOSER workshop held in November 2016 (http://www.closer.ac.uk/event/mixing-modes-measurement-methods-longitudinal-studies/). The workshop and report were funded by a CLOSER Innovation grant awarded to Michaela Benzeval and Annette Jäckle (University of Essex), and Kate Tilling and Dr Andy Skinner (University of Bristol) and are part of a series of three reports (see Jäckle, Gaia, & Benzeval, 2017; Stone & Skinner, 2017)

The merger that led to the formation of the Milky Way's inner stellar halo and thick disk

The assembly process of our Galaxy can be retrieved using the motions and chemistry of individual stars. Chemo-dynamical studies of the nearby halo have long hinted at the presence of multiple components such as streams, clumps, duality and correlations between the stars' chemical abundances and orbital parameters. More recently, the analysis of two large stellar surveys have revealed the presence of a well-populated chemical elemental abundance sequence, of two distinct sequences in the colour-magnitude diagram, and of a prominent slightly retrograde kinematic structure all in the nearby halo, which may trace an important accretion event experienced by the Galaxy. Here report an analysis of the kinematics, chemistry, age and spatial distribution of stars in a relatively large volume around the Sun that are mainly linked to two major Galactic components, the thick disk and the stellar halo. We demonstrate that the inner halo is dominated by debris from an object which at infall was slightly more massive than the Small Magellanic Cloud, and which we refer to as Gaia-Enceladus. The stars originating in Gaia-Enceladus cover nearly the full sky, their motions reveal the presence of streams and slightly retrograde and elongated trajectories. Hundreds of RR Lyrae stars and thirteen globular clusters following a consistent age-metallicity relation can be associated to Gaia-Enceladus on the basis of their orbits. With an estimated 4:1 mass-ratio, the merger with Gaia-Enceladus must have led to the dynamical heating of the precursor of the Galactic thick disk and therefore contributed to the formation of this component approximately 10 Gyr ago. These findings are in line with simulations of galaxy formation, which predict that the inner stellar halo should be dominated by debris from just a few massive progenitors.Comment: 19 pages, 8 figures. Published in Nature in the issue of Nov. 1st, 2018. This is the authors' version before final edit

Museum Websites of the First Wave: The rise of the virtual museum

In this paper, we analyse trends of the first wave of museum websites (from the 1990s to the early 2000s) to understand how the characteristics of the Internet (specifically the World Wide Web), of museum staff, and museum audiences shaped the adoption of technology and new forms of participation and what they can tell us about engagement for museums of the future. The early development of online museum resources parallels the development of the EVA conference, which was establishing itself at a similar time