The Rotterdam Study: 2012 objectives and design update

The Rotterdam Study is a prospective cohort study ongoing since 1990 in the city of Rotterdam in The Netherlands. The study targets cardiovascular, endocrine, hepatic, neurological, ophthalmic, psychiatric, dermatological, oncological, and respiratory diseases. As of 2008, 14,926 subjects aged 45 years or over comprise the Rotterdam Study cohort. The findings of the Rotterdam Study have been presented in over a 1,000 research articles and reports (see www.erasmus-epidemiology.nl/rotterdamstudy). This article gives the rationale of the study and its design. It also presents a summary of the major findings and an update of the objectives and methods

There is no such thing as ‘undisturbed’ soil and sediment sampling: sampler-induced deformation of salt marsh sediments revealed by 3D X-ray computed tomography

Purpose: Within most environmental contexts, the collection of 'undisturbed' samples is widely relied-upon in studies of soil and sediment properties and structure. However, the impact of sampler-induced disturbance is rarely acknowledged, despite the potential significance of modification to sediment structure for the robustness of data interpretation. In this study, 3D-computed X-ray microtomography (μCT) is used to evaluate and compare the disturbance imparted by four commonly-used sediment sampling methods within a coastal salt-marsh. Materials and methods: Paired sediment core samples from a restored salt-marsh at Orplands Farm, Essex, UK were collected using four common sampling methods (push, cut, hammer and gouge methods). Sampling using two different area-ratio cores resulted in a total of 16 cores that were scanned using 3D X-Ray computed tomography, to identify and evaluate sediment structural properties of samples that can be attributed to sampling method. Results and discussion: 3D qualitative analysis identifies a suite of sampling-disturbance structures including gross-scale changes to sediment integrity and substantial modification of pore-space, structure and distribution, independent of sediment strength and stiffness. Quantitative assessment of changes to pore-space and sediment density arising from the four sampling methods offer a means of direct comparison between the impact of depth-sampling methods. Considerable disturbance to samples result from use of push, hammer and auguring samplers, whilst least disturbance is found in samples recovered by cutting and advanced trimming approaches. Conclusions: It is evident that with the small-bore tubes and samplers commonly used in environmental studies, all techniques result in disturbance to sediment structure to a far greater extent than previously reported, revealed by μCT. This work identifies and evaluates for the first time the full nature, extent and significance of internal sediment disturbance arising from common sampling methods

What causes till thickness to change over distance? Answers from Myrdalsjokull, Iceland

Many explanations have been provided for variations of the spatial distribution and thickness of till sheets. This paper gives new insight into the architecture of a stratigraphically distinct till sheet as a function of the type of substratum and preadvance topography at a scale of similar to 10 km. This emphasises the sensitivity of the subglacial system to changes in the basal drainage conditions. The study area is the forefield of Slettjokull at the northern margin of the Myrdalsjokull ice cap, central south Iceland. Here, detailed lithostratigraphical and sedimento logical investigations, including mapping of the thickness for two till units, sediment logging, clast fabric and geotechnical measurements provide a basis for interpretations. The results show that the thickness of a stratigraphically distinct till sheet is directly correlated to the type of substratum. Where the substratum consists of sorted sediments the till is thin. Conversely, the till is thick where the substratum consists of till overlying sorted sediments. A sedimentological model is presented in which till thickness is tied to the variable hydraulic conditions experienced in a deforming subglacial bed. (C) 2003 Elsevier Ltd. All rights reserved

Bounded volatility in the Dutch electoral battlefield: A panel study on the structure of changing vote intentions in the Netherlands during 2006–2010

Dutch elections continue to be the most volatile of Western Europe. But to what extent do voters’ changes in vote intentions continue to be structured by underlying ideological dimensions? This article discusses various theories on the ideological structure of the Dutch party system at the electoral level, and the way they relate to processes of dealignment and realignment. We test these theories using the 1Vandaag Opinion Panel data set, which follows 54 763 respondents in 53 waves between November 2006 and June 2010. We assess individuals’ changes in vote intentions, and analyse the structure in these changes. We draw three conclusions. First, Dutch voters are boundedly volatile and they tend to stick to one of two blocks of parties: a block of traditionally left-wing parties (PvdA, SP, GL) and a block of right-wing parties (CDA, VVD, TON and PVV). D66 functions as the electoral lynchpin between these blocks. Second, the Dutch party system is best described by a sociocultural dimension and a socio-economic dimension. Third, there is support for realignment (along the sociocultural dimension) and continued alignment (along the socio-economic dimension). Yet, we find evidence for widening electoral divisions: there is an electoral gap in the traditionally crowded political centre

n.v.t.

The STONE model for N and P emission to groundwater and surface waters has been developed to evaluate the environmental benefits of eutrophication abatement plans. Due to possible severe socio-economic consequences of these abatement plans, it is of importance that the model is well documented, calibrated and tested. This report describes the first phase of the STONE test. STONE results were compared with previously published results and with monitoring data. About 13,000 recent point source observations of nitrate in the upper groundwater were available, along with several hundred of observations showing N and P in local surface water systems. During this phase of the STONE test, the observations were lumped to statistical summaries, such as frequency distributions, means, etc. It was concluded that the STONE results compared quite well with these observed values. These results, however, present only limited information about underlying processes, spatial patterns and temporal dynamics. These issues will be addressed during the second phase of the STONE test. Results from the second phase of the STONE test will be reported in 2002.STONE is ontwikkeld om landsdekkend voor Nederland de effecten van bemesting en mestbeleid op de emissies van stikstof en fosfaat uit de landbouw naar grond- en oppervlaktewater te verkennen. De nadruk in de hier gerapporteerde plausibiliteitsstudie ligt op vaststelling van de geloofwaardigheid, het realiteitsgehalte, van getalswaarden en ruimtelijke verdeling van data in STONE versie 2.0. Hiervoor zijn resultaten van STONE 2.0 globaal vergeleken met meetgegevens en met eerdere modelresultaten. Conclusie is dat STONE 2.0 meer plausibel is dan STONE 1.3, de versie gebruikt voor Milieuverkenning 5. De resultaten van deze studie vormen een belangrijk input voor het rapport "De status van het rekeninstrumentarium STONE versie 2.0". In het rapport wordt het toepassingsbereik van STONE 2.0 beschreven voor potentiele gebruikers en afnemers

n.v.t.

STONE is ontwikkeld om landsdekkend voor Nederland de effecten van bemesting en mestbeleid op de emissies van stikstof en fosfaat uit de landbouw naar grond- en oppervlaktewater te verkennen. De nadruk in de hier gerapporteerde plausibiliteitsstudie ligt op vaststelling van de geloofwaardigheid, het realiteitsgehalte, van getalswaarden en ruimtelijke verdeling van data in STONE versie 2.0. Hiervoor zijn resultaten van STONE 2.0 globaal vergeleken met meetgegevens en met eerdere modelresultaten. Conclusie is dat STONE 2.0 meer plausibel is dan STONE 1.3, de versie gebruikt voor Milieuverkenning 5. De resultaten van deze studie vormen een belangrijk input voor het rapport "De status van het rekeninstrumentarium STONE versie 2.0". In het rapport wordt het toepassingsbereik van STONE 2.0 beschreven voor potentiele gebruikers en afnemers.The STONE model for N and P emission to groundwater and surface waters has been developed to evaluate the environmental benefits of eutrophication abatement plans. Due to possible severe socio-economic consequences of these abatement plans, it is of importance that the model is well documented, calibrated and tested. This report describes the first phase of the STONE test. STONE results were compared with previously published results and with monitoring data. About 13,000 recent point source observations of nitrate in the upper groundwater were available, along with several hundred of observations showing N and P in local surface water systems. During this phase of the STONE test, the observations were lumped to statistical summaries, such as frequency distributions, means, etc. It was concluded that the STONE results compared quite well with these observed values. These results, however, present only limited information about underlying processes, spatial patterns and temporal dynamics. These issues will be addressed during the second phase of the STONE test. Results from the second phase of the STONE test will be reported in 2002.DG