Carbon isotope composition of middle Eocene leaves from the Messel Pit, Germany

A b s t r a c t The 13 C/ 12 C ratios (δ 13 C) of leaves from the middle Eocene of the Messel Pit (Middle Messel Formation) were measured to determine the ratios of leaf-internal to ambient carbon dioxide concentration (c i /c a ) for the respective time. For extant plants this parameter provides information about their ecophysiological state. Fossil leaves belonging to three species were analyzed: Laurophyllum lanigeroides (Lauraceae), Daphnogene crebrigranosa (Lauraceae) and Rhodomyrtophyllum sinuatum (Myrtaceae). In order to determine the range of δ 13 C across a single leaf (intra-leaf variability) samples from the basal, central and apical region were separately prepared and analyzed. The results are compared to δ 13 C and c i /c a ratios in extant evergreen Lauraceae (Laurus nobilis, Cinnamomum camphora, Persea americana) and Myrtaceae (Myrtus communis, Psidium littorale/cattleianum). The δ 13 C of the fossil cuticles varies from -30 ‰ to -27 ‰ in the Lauraceae and from -29 ‰ to -26 ‰ in the Myrtaceae, which are typical ranges for extant C 3 -plants. Results of intra-leaf analyses indicate that δ 13 C varies slightly across the leaves but intra-leaf variability is statistically not signifi cant. Mean Eocene c i /c a -ratios as calculated from the measured δ 13 C values varied from 0.78 to 0.87. The c i /c a -ratios of extant Lauraceae are substantially lower (average 0.69) than for the fossil material. In Myrtaceae, c i /c a -ratios are almost the same for extant and fossil material (extant Myrtaceae average at about 0.8). K e y w o r d s : middle Eocene, Messel, leaves, carbon isotopes, c i /c a -ratio. Z u s a m m e n f a s s u n g Das 13 C/ 12 C-Verhältnis (δ 13 C) von fossilen Blättern aus dem Mitteleozän der Grube Messel (Mittlere Messel Formation) wurde gemessen und daraus das Verhältnis von blattinternem zu atmosphärischem Kohlendioxid (c i /c a ) für die betreffende Zeit bestimmt. Bei heutigen Pfl anzen erlaubt diese Größe eine Einschätzung des ökophysiologi-schen Zustands. Es wurden die Blätter von drei fossilen Arten analysiert: Laurophyllum lanigeroides (Lauraceae), Daphnogene crebrigranosa (Lauraceae) und Rhodomyrtophyllum sinuatum (Myrtaceae). Um Schwankungen des δ 13 C innerhalb eines Blattes (blattinterne Variabilität) bestimmen zu können, wurden getrennte Proben aus dem basalen, dem mittleren und dem apikalen Bereich genommen und analysiert. Die Ergebnisse wurden mit dem δ 13 C und c i /c a rezenter immergrüner Lauraceae (Laurus nobilis, Cinnamomum camphora, Persea americana) und Myrtaceae (Myrtus communis, Psidium littorale/cattleianum) verglichen. Das δ 13 C der fossilen Kutikulen variiert von -30 ‰ bis -27 ‰ innerhalb der Lauraceae und von -29 ‰ bis -26 ‰ innerhalb der Myrtaceae, was im Bereich moderner C 3 -Pfl anzen liegt. Die Ergebnisse der blattinternen Analysen zeigen, dass der δ 13 C-Wert innerhalb eines Blattes variiert, diese blattinterne Variabilität statistisch jedoch nicht signifi kant ist. Das c i /c a -Verhältnis für das Mitteleozän, das mit den gemessenen δ 13 C-Werten berechnet wurde, schwankt zwischen durchschnittlich 0,78 und 0,87. Die c i /c a -Verhältnisse für rezente Lauraceae sind deutlich geringer (durchschnittlich 0,69) als die für die beiden fossilen Arten errechneten Werte. Bei den Myrtaceae unterscheiden sich die mitteleozänen und rezenten c i /c a -Verhältnisse kaum, rezente Myrtaceae liegen hier durchschnittlich bei etwa 0,8

Early Paleogene wildfires in peat-forming environments at Schöningen, Germany

AbstractWildfire activity in early Paleogene greenhouse conditions can be used as an analogue to gauge the effect of future warming trends on wildfire in the current climate system. Inertinite (fossil charcoal in coal) from 11 autochthonous early Paleogene lignite seams from the Schöningen mine (Germany) was quantified using macerations, in situ pillars and industry standard crushed samples. A new three transect method was developed to quantify in situ charcoal. The combination of in situ pillars and crushed samples accounts for temporal and spatial variation in charcoal through a stratigraphically oriented pillar, whilst maintaining comparability with industry standards and previous work. Charcoal occurs as a range of randomly distributed particle sizes, indicating that fires were burning locally in the Schöningen peat-forming environment and in the surrounding areas, but according to petrological data, not in an episodic or periodic pattern. Although charcoal abundance is low (relative to previous high fire worlds such as the Cretaceous), three quantitative and semi-quantitative methods show increased wildfire activity (relative to the modern world) in the warmest parts of the early Paleogene. As atmospheric oxygen levels stabilised to modern values and precipitation and humidity became the main control on wildfire, increased rainfall followed by drier intervals would have created an environment rich in dry fuel in which wildfires could easily propagate if humidity was low enough. In the later part of the Early Eocene (Ypresian) charcoal abundance fell to levels similar to those found in modern peats. This indicates that the transition to the modern low fire world occurred within the Early Eocene, earlier than previous records suggest

Metabolic Pathways and Potencies of New Fentanyl Analogs

Up to now, little is known about the metabolic pathways of new fentanyl analogs that have recently emerged on the drug markets worldwide with high potential for producing addiction and severe adverse effects including coma and death. For some of the compounds, limited information on the metabolism has been published, however, for others so far no information is available. Considering the well characterized metabolism of the pharmaceutically used opioid fentanyl and the so far available data, the metabolism of the new fentanyl analogs can be anticipated to generally involve reactions like hydrolysis, hydroxylation (and further oxidation steps), N- and O-dealkylation and O-methylation. Furthermore, phase II metabolic reactions can be expected comprising glucuronide or sulfate conjugate formation. When analyzing blood and urine samples of acute intoxication cases or fatalities, the presence of metabolites can be crucial for confirmation of the uptake of such compounds and further interpretation. Here we present a review on the metabolic profiles of new fentanyl analogs responsible for a growing number of severe and fatal intoxications in the United States, Europe, Canada, Australia, and Japan in the last years, as assessed by a systematic search of the scientific literature and official reports

The N Terminus of Adhesion G Protein–Coupled Receptor GPR126/ ADGRG6 as Allosteric Force Integrator

The adhesion G protein–coupled receptor (aGPCR) GPR126/ADGRG6 plays an important role in several physiological functions, such as myelination or peripheral nerve repair. This renders the receptor an attractive pharmacological target. GPR126 is a mechano-sensor that translates the binding of extracellular matrix (ECM) molecules to its N terminus into a metabotropic intracellular signal. To date, the structural requirements and the character of the forces needed for this ECM-mediated receptor activation are largely unknown. In this study, we provide this information by combining classic second-messenger detection with single-cell atomic force microscopy. We established a monoclonal antibody targeting the N terminus to stimulate GPR126 and compared it to the activation through its known ECM ligands, collagen IV and laminin 211. As each ligand uses a distinct mode of action, the N terminus can be regarded as an allosteric module that can fine-tune receptor activation in a context-specific manner

Mid-latitude continental temperatures through the early Eocene in western Europe

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are increasingly used to reconstruct mean annual air temperature (MAAT) during the early Paleogene. However, the application of this proxy in coal deposits is limited and brGDGTs have only been detected in immature coals (i.e. lignites). Using samples recovered from Schöningen, Germany (∼48°N palaeolatitude), we provide the first detailed study into the occurrence and distribution of brGDGTs through a sequence of early Eocene lignites and associated interbeds. BrGDGTs are abundant and present in every sample. In comparison to modern studies, changes in vegetation type do not appear to significantly impact brGDGT distributions; however, there are subtle differences between lignites – representing peat-forming environments – and siliciclastic nearshore marine interbed depositional environments. Using the most recent brGDGT temperature calibration (MATmr) developed for soils, we generate the first continental temperature record from central-western continental Europe through the early Eocene. Lignite-derived MAAT estimates range from 23 to 26 °C while those derived from the nearshore marine interbeds exceed 20 °C. These estimates are consistent with other mid-latitude environments and model simulations, indicating enhanced mid-latitude, early Eocene warmth. In the basal part of the section studied, warming is recorded in both the lignites (∼2 °C) and nearshore marine interbeds (∼2–3 °C). This culminates in a long-term temperature maximum, likely including the Early Eocene Climatic Optimum (EECO). Although this long-term warming trend is relatively well established in the marine realm, it has rarely been shown in terrestrial settings. Using a suite of model simulations we show that the magnitude of warming at Schöningen is broadly consistent with a doubling of CO2, in agreement with late Paleocene and early Eocene pCO2 estimates

Plastid DNA sequences and oospore characters of some European taxa of Tolypella section Tolypella (Characeae) identify five clusters, including one new cryptic Tolypella taxon from Sardinia, but they do not coincide with current morphological descriptions

In Europe, the genus Tolypella (Characeae) comprises four to eight Tolypella taxa in sections Rothia and Tolypella that have been distinguished by vegetative morphology and gametangial characters such as antheridial size and oospore wall ornamentation. However, morphological differentiation is difficult in some cases due to overlapping and variable vegetative features, which in many cases are difficult to observe clearly. To clarify the taxonomic status of the five European taxa of Tolypella in section Tolypella, sequence data of the plastid genes atpB, rbcL and psbC for Tolypella glomerata (Desv.) Leonh., Tolypella hispanica Allen, Tolypella nidifica (O.F. Müll.) A. Braun, Tolypella normaniana (Nordst.) Nordst. and Tolypella salina Cor. were combined with data on oospore morphology, including oospore wall ornamentation. Gene sequence data identified five distinct clusters, but they were not consistent with the morphologically identified five taxa. T. glomerata consisted of some of the samples morphologically identified as T. glomerata and seven samples of T. normaniana, while the remaining T. glomerata samples clustered with specimens of unclear affiliation (Tolypella sp.). We identified two clusters of T. hispanica within the European material: cluster T. hispanica I consisted of samples from various locations, whereas the second cluster (T. hispanica II) consisted of samples of T. hispanica from Sardinia Island. The remaining cluster consisted of all the specimens that had been determined as T. salina or T. nidifica in addition to two specimens of T. normaniana. Oospore morphology was most clearly distinguishable for T. glomerata. Oospore characteristics for all other taxa were not as informative but showed some geographical and/or environmentally influenced differences, especially for T. nidifica and T. salina. Our results suggest the need to further check the different taxonomy of Tolypella sect. Tolypella in which specimens normally identified as T. glomerata might be two different taxa, T. glomerata and an unidentified taxon; T. nidifica and T. salina are not separate taxa; T. normaniana is a diminutive variant of two different Tolypella taxa; and T. hispanica comprises two different taxa, one from the Mediterranean island Sardinia.publishedVersio

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac