Mapping tooth surface loss with a fixed-base stereo camera

Change detection of tooth surface loss in the cervical region of a tooth replica has been performed using a fixed-base stereoscopic camera, consisting of two SLR digital cameras with lenses of fixed focal length. Commercial digital photogrammetric and calibration software was used to perform a convergent multi-station calibration with an artefact comprising a transilluminated planar array and a tiered object exhibiting optical texture. Digital surface models of a tiered test object and a tooth surface containing a non-carious cervical lesion were generated from stereo-imagery. The accuracy of automatic mass point measurement of a planar surface was 4 ± 13 μm in Z. The sensitivity of change detection on mapped tooth replicas was 0·03 mm with change ranging from 0·03 to 0·07 mm per annum. Different rates of change were clearly evident in different areas at different times. The results of this investigation suggest that annual change detection studies will provide a clearer picture of the pattern of tooth surface loss and, in combination with other analytical techniques, a more detailed explanation of the natural history of these lesions.     

Videogrammetric monitoring of as-built membrane roof structures

A monitoring system that uses applied geomatics techniques, including videogrammetry and terrestrial laser scanning, has been developed in order to investigate the dynamic behaviour of as-built membrane roof structures. To accommodate the problems involved in measuring such roof structures, examples of which include uniform surface texture and unreachable height, the system adopts a non-contact targeting methodology to substitute for traditional control techniques. In-house software was developed for processing the acquired video imagery in order to produce a sequential surface model of the membrane. This paper firstly reports on experiments conducted to demonstrate that the monitoring system was capable of measuring representative test structures with a precision of better than ±1 mm. To prove the feasibility and transferability of the system, videogrammetric monitoring campaigns were subsequently performed at a real-world test site where two different types of membrane structure were observed. The sequential 3D surface models that were generated allowed the displacement of the membrane surfaces to be investigated over a period, during which the range of the movement reached over 20 mm. The information acquired from the system is proving to be of great value to structural engineers involved in research and development of such membrane structures.     

Isotope Ratio Determination in the Earth and Environmental Sciences: Developments and Applications in 2006–2007

This review documents developments and applications in the field of isotope ratio determination, as reflected in the literature for the Earth and Environmental Sciences for the years 2006 and 2007. The emphasis is predominantly on applications, reflecting the enormous diversity of problems to which isotopic analysis can now be applied, but viewed in the context of rapid uptake of new analytical technologies and significant new drivers of research output.     

GGR Critical Review of Analytical Developments in 2006–2007

In 2005 the Geostandards and Geoanalytical Research editorial team, in the true spirit of scientific endeavour, embarked on an experiment of our own. We decided to trial a new kind of review, somewhat different from those more typically observed in journals, and one that would provide readers with a summary of analytical developments across a broad range of topics appropriate to the Earth sciences. The first contribution of this kind appeared in 2005, and reported on developments in 2003 (Hergt et al. 2005). The second, this time a biennial review, was published in 2006 and reported on highlights of the 2004 and 2005 literature (Hergt et al. 2006). Based on reprint requests, positive remarks at conferences and strong citations we consider the experiment a resounding success and proudly present here the third in this series. This comprises six individual review sections that cover the main analytical technologies and topical application fields in geoanalysis and geochemistry, including geological and environmental reference materials, ICP‐thermal and secondary ionisation‐mass spectrometry, as well as neutron activation analysis, X‐ray fluorescence and atomic absorption spectrometry.     

Spatial discovery and the research library

Academic libraries have always supported research across disciplines by integrating access to diverse contents and resources. They now have the opportunity to reinvent their role in facilitating interdisciplinary work by offering researchers new ways of sharing, curating, discovering, and linking research data. Spatial data and metadata support this process because location often integrates disciplinary perspectives, enabling researchers to make their own research data more discoverable, to discover data of other researchers, and to integrate data from multiple sources. The Center for Spatial Studies at the University of California, Santa Barbara (UCSB) and the UCSB Library are undertaking joint research to better enable the discovery of research data and publications. The research addresses the question of how to spatially enable data discovery in a setting that allows for mapping and analysis in a GIS while connecting the data to publications about them. It suggests a framework for an integrated data discovery mechanism and shows how publications may be linked to associated data sets exposed either directly or through metadata on Esri's Open Data platform. The results demonstrate a simple form of linking data to publications through spatially referenced metadata and persistent identifiers. This linking adds value to research products and increases their discoverability across disciplinary boundaries.     

Spatial and ecologic distribution of neglected microinvertebrate communities across endangered ecosystems: meiofauna in Bali (Indonesia)

Biodiversity estimations, particularly in vulnerable tropical regions, are essential to understanding ecosystem structure, function and conservation. While threats to marine and terrestrial ecosystems have fueled increased interest in biodiversity research, information on meiofauna, a key trophic and ecologic community of microscopic organisms that lives within sediments, is still lacking. Here we report the results of a faunistic investigation conducted in Bali, Indonesia. The results reveal that the biodiversity of marine meiofauna in Bali is very high. Meiofauna from coral reefs, sand flats and seagrass beds differed significantly in abundance and diversity. Nonetheless, overall community compositions show that meiofauna communities are affected by environmental variables. The high meiofaunal diversity observed in Bali, a low diversity region of the Coral Triangle, indicates the importance of further meiofaunal research across this region and across a broader diversity of habitats. The data presented provide an important baseline for future studies on biodiversity conservation in the face of environmental changes due to anthropogenic impacts and/or natural events.     

Making the EU Emissions Trading System: The European Commission as an entrepreneurial epistemic leader

The EU has developed the first and largest international emissions trading system in the world. This development is puzzling due to the EU's scepticism to international emissions trading in greenhouse gases (GHGs) in the run-up to the 1997 Kyoto Protocol. This article analyses how the EU ETS was initiated in the first place mainly from the perspectives of Liberal intergovernmentalism (LI) and multi-level governance (MLG). LI emphasises change in the positions of the EU member states as the key to understand what happened and why, whereas MLG opens up for change in the position of supranational entrepreneurial leaders as the key explanation. The main conclusion is that entrepreneurial epistemic leadership exercised by the European Commission was crucial for making the EU ETS. The principal means of leadership involved building up independent expertise on how an EU ETS could be designed, and mobilizing support from state and non-state actors at various levels of decision-making. This type of leadership may be needed more generally to deal with challenges characterized by high scientific uncertainty and social complexity in which learning is pertinent, such as climate change.     

Biomarkers and compound-specific stable carbon isotope of n-alkanes in crude oils from Eastern Llanos Basin,Colombia

Representative samples of crude oils from Cusiana, Cupiagua, Apiay, Castilla and Chichimene fields in the Eastern Llanos Basin of Colombia were analyzed to determine its compound-specific stable carbon isotope composition (CSIA) using gas chromatography–isotopic ratio–mass spectrometry (GC–IRMS). GC–IRMS analyses of n-alkanes allowed differentiating between Cretaceous and Cretaceous/Tertiary oil samples. Cretaceous sourced samples have δ¹³C-enriched values than Cretaceous/Tertiary sourced samples; the heavier isotope composition of these samples is due to their major terrigenous organic matter input. Their isotope distribution patterns suggest significant algal and/or bacterial contribution (marine origin). The analysis of the n-alkane fractions by GC–IRMS confirms that the organic matter has marine origin in those samples from Cusiana, Cupiagua and Apiay while Castilla and Chichimene have marine origin with terrestrial inputs. The results were confirmed by gas chromatography/FID and gas chromatography/mass spectrometry (GC/MS). Basic geochemical composition show that samples from Cupiagua/Cusiana fields and Apiay/Castilla/Chichimene fields in the Llanos basin, Colombia present different characteristics reflecting a specific for each depositional environment.