Impact of the Diamond Light Source on research in Earth and environmental sciences: current work and future perspectives.

Diamond Light Source Ltd celebrated its 10th anniversary as a company in December 2012 and has now accepted user experiments for over 5 years. This paper describes the current facilities available at Diamond and future developments that enhance its capacities with respect to the Earth and environmental sciences. A review of relevant research conducted at Diamond thus far is provided. This highlights how synchrotron-based studies have brought about important advances in our understanding of the fundamental parameters controlling highly complex mineral–fluid–microbe interface reactions in the natural environment. This new knowledge not only enhances our understanding of global biogeochemical processes, but also provides the opportunity for interventions to be designed for environmental remediation and beneficial use

Morphological and Geochemical Evidence of Eumelanin Preservation in the Feathers of the Early Cretaceous Bird, Gansus yumenensis

Recent studies have shown evidence for the preservation of colour in fossilized soft tissues by imaging melanosomes, melanin pigment containing organelles. This study combines geochemical analyses with morphological observations to investigate the preservation of melanosomes and melanin within feathers of the Early Cretaceous bird, Gansus yumenensis. Scanning electron microscopy reveals structures concordant with those previously identified as eumelanosomes within visually dark areas of the feathers but not in lighter areas or sedimentary matrices. Fourier transform infrared analyses show different spectra for the feathers and their matrices; melanic functional groups appear in the feather including carboxylic acid and ketone groups that are not seen in the matrix. When mapped, the carboxylic acid group absorption faithfully replicates the visually dark areas of the feathers. Electron Paramagnetic Resonance spectroscopy of one specimen demonstrates the presence of organic signals but proved too insensitive to resolve melanin. Pyrolysis gas chromatography mass spectrometry shows a similar distribution of aliphatic material within both feathers that are different from those of their respective matrices. In combination, these techniques strongly suggest that not only do the feathers contain endogenous organic material, but that both geochemical and morphological evidence supports the preservation of original eumelanic pigment residue

Identification of Shell Colour Pigments in Marine Snails Clanculus pharaonius and C. margaritarius (Trochoidea; Gastropoda)

This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. https://creativecommons.org/publicdomain/zero/1.0/ The attached file is the published version of the article

Selective Serotonin Reuptake Inhibitor (SSRI) Antidepressants in Pregnancy and Congenital Anomalies: Analysis of Linked Databases in Wales, Norway and Funen, Denmark

Background: Hypothesised associations between in utero exposure to selective serotonin reuptake inhibitors (SSRIs) and congenital anomalies, particularly congenital heart defects (CHD), remain controversial. We investigated the putative teratogenicity of SSRI prescription in the 91 days either side of first day of last menstrual period (LMP). Methods and Findings: Three population-based EUROCAT congenital anomaly registries- Norway (2004–2010), Wales (2000–2010) and Funen, Denmark (2000–2010)—were linked to the electronic healthcare databases holding prospectively collected prescription information for all pregnancies in the timeframes available. We included 519,117 deliveries, including foetuses terminated for congenital anomalies, with data covering pregnancy and the preceding quarter, including 462,641 with data covering pregnancy and one year either side. For SSRI exposures 91 days either side of LMP, separately and together, odds ratios with 95% confidence intervals (ORs, 95%CI) for all major anomalies were estimated. We also explored: pausing or discontinuing SSRIs preconception, confounding, high dose regimens, and, in Wales, diagnosis of depression. Results were combined in meta-analyses. SSRI prescription 91 days either side of LMP was associated with increased prevalence of severe congenital heart defects (CHD) (as defined by EUROCAT guide 1.3, 2005) (34/12,962 [0.26%] vs. 865/506,155 [0.17%] OR 1.50, 1.06–2.11), and the composite adverse outcome of 'anomaly or stillbirth' (473/12962, 3.65% vs. 15829/506,155, 3.13%, OR 1.13, 1.03–1.24). The increased prevalence of all major anomalies combined did not reach statistical significance (3.09% [400/12,962] vs. 2.67% [13,536/506,155] OR 1.09, 0.99–1.21). Adjusting for socio-economic status left ORs largely unchanged. The prevalence of anomalies and severe CHD was reduced when SSRI prescriptions were stopped or paused preconception, and increased when >1 prescription was recorded, but differences were not statistically significant. The dose-response relationship between severe CHD and SSRI dose (meta-regression OR 1.49, 1.12–1.97) was consistent with SSRI-exposure related risk. Analyses in Wales suggested no associations between anomalies and diagnosed depression. Conclusion: The additional absolute risk of teratogenesis associated with SSRIs, if causal, is small. However, the high prevalence of SSRI use augments its public health importance, justifying modifications to preconception care

Trace element and isotopic zonation in vein calcite from the Mendip Hills, UK, with spatial-process correlation analysis

High-resolution Scanning Proton Microprobe (SPM) analyses of fissure filling calcite (from the Mendip Hills, UK) show fine-scale chemical zonation patterns in Fe and Mn concentrations from fissure centre to wall. These fluctuations are sharp and steep (peaks of 0.01-0.1 mm width), with concentrations changing by as much as 8000 ppm. Zonation in Pb and Zn is similar to that obtained for Mn and Fe, and maxima in the concentrations of these two elements are correlated with maxima in Mn concentration. Longer wavelength fluctuations (1.0-3.0 mm) are evident in data obtained for Sr, for which changes in concentration are gradual and fluctuate by at most 500 ppm. Auto-correlation calculations show that oscillations in the Mn and Fe data have a wavelength of 0.9-1.3 mm in contrast to auto-correlations and cross-correlations with Zn and Pb which indicate wavelengths of 0.4 mm. Strontium correlations indicate a peak-to-trough distance of 4.2 mm, which implies a much longer wavelength fluctuation in the Sr data. Cross-correlations also clearly show that Pb and Zn concentrations co-vary strongly (cross-correlation function value of 0.7 at lag 0) but all other cross-correlations are weak. These computations demonstrate that intrinsic controls on trace element partitioning cannot alone account for the observed patterns. Long period fluctuations are interpreted to result from a sustained change in the starting composition of the aqueous phase, while the high frequency oscillations are interpreted to be caused by mixing reactions among fluids that have reacted with different portions of country rock prior to calcite precipitation. Analyses of the carbon, oxygen, and strontium isotopes from these vein calcites have also been completed. δ18O plotted as a function of δ13C results in an inverted triangular array. We interpret this, along with the trace element data, as resulting from three distinct fluids participating in the formation of these fissure fills: a low Mn-Fe, high Sr marine fluid (apex at δ18O = 0, δ13C = +4; both relative to PDB); a high Mn-Fe, low Sr hydrothermal fluid (+2, -9.5); and a low Mn-Fe, low Sr meteoric fluid (-12, -5). The trace element and isotopic compositions of this zoned calcite thus document the following processes in detail: (1) the formation of a meteoric fissure system (Triassic), (2) reactions with hotter and more reduced circulating fluids, and (3) the subsequent flooding of the system with seawater during transgression of the area (Rhaetian-Early Jurassic; Strontium isotopic data from a belemnite located within one of the fissures gives an Early Jurassic age of approximately 198 Ma). Hot, reduced fluids with high metal concentrations were probably forced up into these fissures by seismic pumping during movement on associated regional faults. Copyright © 1997 Elsevier Science Ltd