Presence of an unusual 17α,21β(H)-bacteriohopanetetrol in Holocene sediments from Ace Lake (Antarctica)

Author Posting. © Elsevier B.V., 2008. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Organic Geochemistry 39 (2008): 1029-1032, doi:10.1016/j.orggeochem.2008.01.008.Whilst investigating the intact biohopanoid (bacteriohopanepolyol, BHP) distribution in Holocene sediments from Ace Lake (Antarctica), we have identified the presence of ab- bacteriohopanetetrol in sediments aged up to 9400 years BP. To our knowledge, this is the first time that an intact polyfunctionalised BHP with the “geological” 17α,21β(H) configuration has been identified in a sediment. Previously, this structure has only been observed in species of the nitrogen fixing bacterium Frankia. Its presence here in the sedimentary environment has implications for the interpretation of hopanoid ββ/αβ ratios in the geological record.This work was supported by grants from the Australian Antarctic Science Advisory Committee (1166 to J.V.) and the Netherlands Organization for Scientific Research (NWO; 851.20.006 to J.S.S.D. and NWO-VENI grant 016.051.014 to M.J.L.C.) We gratefully acknowledge the NERC for funding (HMT) and The Science Research Infrastructure Fund (SRIF) from HEFCE for funding the purchase of the Thermo Electron Finnigan LCQ ion trap mass spectrometer

Statistical Multifragmentation of Non-Spherical Expanding Sources in Central Heavy-Ion Collisions

We study the anisotropy effects measured with INDRA at GSI in central collisions of Xe+Sn at 50 A.MeV and Au+Au at 60, 80, 100 A.MeV incident energy. The microcanonical multifragmentation model with non-spherical sources is used to simulate an incomplete shape relaxation of the multifragmenting system. This model is employed to interpret observed anisotropic distributions in the fragment size and mean kinetic energy. The data can be well reproduced if an expanding prolate source aligned along the beam direction is assumed. An either non-Hubblean or non-isotropic radial expansion is required to describe the fragment kinetic energies and their anisotropy. The qualitative similarity of the results for the studied reactions suggests that the concept of a longitudinally elongated freeze-out configuration is generally applicable for central collisions of heavy systems. The deformation decreases slightly with increasing beam energy.Comment: 35 pages, 19 figures, submitted to Nuclear Physics

Dragon-kings: mechanisms, statistical methods and empirical evidence

This introductory article presents the special Discussion and Debate volume "From black swans to dragon-kings, is there life beyond power laws?" published in Eur. Phys. J. Special Topics in May 2012. We summarize and put in perspective the contributions into three main themes: (i) mechanisms for dragon-kings, (ii) detection of dragon-kings and statistical tests and (iii) empirical evidence in a large variety of natural and social systems. Overall, we are pleased to witness significant advances both in the introduction and clarification of underlying mechanisms and in the development of novel efficient tests that demonstrate clear evidence for the presence of dragon-kings in many systems. However, this positive view should be balanced by the fact that this remains a very delicate and difficult field, if only due to the scarcity of data as well as the extraordinary important implications with respect to hazard assessment, risk control and predictability.Comment: 20 page

Autonomic symptoms are common and are associated with overall symptom burden and disease activity in primary Sjögren's syndrome

Objectives - To determine the prevalence of autonomic dysfunction (dysautonomia) among patients with primary Sjögren's syndrome (PSS) and the relationships between dysautonomia and other clinical features of PSS. Methods - Multicentre, prospective, cross-sectional study of a UK cohort of 317 patients with clinically well-characterised PSS. Symptoms of autonomic dysfunction were assessed using a validated instrument, the Composite Autonomic Symptom Scale (COMPASS). The data were compared with an age- and sex-matched cohort of 317 community controls. The relationships between symptoms of dysautonomia and various clinical features of PSS were analysed using regression analysis. Results - COMPASS scores were significantly higher in patients with PSS than in age- and sex-matched community controls (median (IQR) 35.5 (20.9–46.0) vs 14.8 (4.4–30.2), p32.5, a cut-off value indicative of autonomic dysfunction. Furthermore, the COMPASS total score correlated independently with EULAR Sjögren's Syndrome Patient Reported Index (a composite measure of the overall burden of symptoms experienced by patients with PSS) (β=0.38, p<0.001) and disease activity measured using the EULAR Sjögren's Syndrome Disease Activity Index (β=0.13, p<0.009). Conclusions - Autonomic symptoms are common among patients with PSS and may contribute to the overall burden of symptoms and link with systemic disease activity

An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types