244 research outputs found

    Modern Raman Spectroscopy: A Practical Approach

    Get PDF

    New sub-millimeter limits on dust in the 55 Cancri planetary system

    Get PDF
    We present new, high-sensitivity sub-millimeter observations towards 55 Cancri, a nearby G8 star with one, or possibly two, known planetary companion(s). Our 850 Ό\mum map, obtained with the SCUBA instrument on the James Clerk Maxwell Telescope, shows three peaks of emission at the 2.5 mJy level in the vicinity of the star's position. However, the observed peaks are 25\arcsec--40\arcsec away from the star and a deep RR-band optical image reveals faint point sources that coincide with two of the sub-millimeter peaks. Thus, we do not find evidence for dust emission spatially associated with 55 Cancri. The excess 60 Ό\mum emission detected with ISO may originate from one or more of the 850 Ό\mum peaks that we attribute to background sources. Our new results, together with the HST/NICMOS coronographic images in the near-infrared, place stringent limits on the amount of dust in this planetary system, and argue against the existence of a detectable circumstellar dust disk around 55 Cnc.Comment: 11 pages, 2 PostScript figures, to appear in The Astrophysical Journal Letter

    Minimally invasive approach to lumbosacral decompression in a cadaveric canine model

    Get PDF
    AIMS : To determine efficacy of a minimally invasive (MI) surgical approach using a human MI lumbar retractor for canine lumbosacral dorsal laminectomy and partial discectomy and to compare this technique to the standard open surgical (OS) approach. METHODS : Lumbosacral dorsal laminectomy and partial discectomy was performed on 16 largebreed canine cadavers using either a standard OS (n=8) or MI (n=8) approach. Skin and fascial incision length, procedure time, and intraoperative complications were recorded. Postoperatively specimens were evaluated for laminectomy and discectomy dimensions, and visible damage to the cauda equina and exiting nerve roots. RESULTS : Median length of skin and fascial incisions in the OS group were longer than in the MI group (p<0.001). Median laminectomy length was similar between both approaches (p=0.234) but width was greater for the MI than OS approach (p=0.002). Both approaches achieved similar partial discectomy width (p=0.279). Overall surgical time was longer for MI approaches compared to OS, with a median of 18.5 (min 15.5, max 21.8) minutes for MI compared to 14.6 (min 13.1, max 16.9) minutes for OS (p=0.001). CONCLUSIONS : The MI approach reduced incision lengths while retaining comparable laminectomy and discectomy dimensions. For this in vitro model the MI approach required more time to complete, but this difference may not be relevant in clinical cases. CLINICAL RELEVANCE : Dogs undergoing lumbosacral dorsal laminectomy are commonly large-breed dogs. The traditional open approach requires a large skin incision and soft tissue dissection, especially in overweight animals. A MI approach accomplishing the same surgical result while minimising soft tissue trauma could reduce post-operative pain and recovery time, and may lower wound-related complications. Clinical studies are needed to confirm postoperative benefit and assess operating times in vivo.http://www.tandfonline.com/loi/tnzv202017-03-31hb2016Production Animal Studie

    Dust in the 55 Cancri planetary system

    Full text link
    The presence of debris disks around ∌\sim 1-Gyr-old main sequence stars suggests that an appreciable amount of dust may persist even in mature planetary systems. Here we report the detection of dust emission from 55 Cancri, a star with one, or possibly two, planetary companions detected through radial velocity measurements. Our observations at 850ÎŒ\mum and 450ÎŒ\mum imply a dust mass of 0.0008-0.005 Earth masses, somewhat higher than that in the the Kuiper Belt of our solar system. The estimated temperature of the dust grains and a simple model fit both indicate a central disk hole of at least 10 AU in radius. Thus, the region where the planets are detected is likely to be significantly depleted of dust. Our results suggest that far-infrared and sub-millimeter observations are powerful tools for probing the outer regions of extrasolar planetary systems.Comment: 8 pages and 2 figures, to appear in the Astrophysical Journa

    Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)

    Get PDF
    Recommendations are given concerning the terminology of concepts and methods used in spectroscopy in analytical chemistry, covering nuclear magnetic resonance spectroscopy, atomic spectroscopy, and vibrational spectroscopy

    Low-latency gravitational wave alert products and their performance in anticipation of the fourth LIGO-Virgo-KAGRA observing run

    Full text link
    Multi-messenger searches for binary neutron star (BNS) and neutron star-black hole (NSBH) mergers are currently one of the most exciting areas of astronomy. The search for joint electromagnetic and neutrino counterparts to gravitational wave (GW)s has resumed with Advanced LIGO (aLIGO)'s, Advanced Virgo (AdVirgo)'s and KAGRA's fourth observing run (O4). To support this effort, public semi-automated data products are sent in near real-time and include localization and source properties to guide complementary observations. Subsequent refinements, as and when available, are also relayed as updates. In preparation for O4, we have conducted a study using a simulated population of compact binaries and a Mock Data Challenge (MDC) in the form of a real-time replay to optimize and profile the software infrastructure and scientific deliverables. End-to-end performance was tested, including data ingestion, running online search pipelines, performing annotations, and issuing alerts to the astrophysics community. In this paper, we present an overview of the low-latency infrastructure as well as an overview of the performance of the data products to be released during O4 based on a MDC. We report on expected median latencies for the preliminary alert of full bandwidth searches (29.5 s) and for the creation of early warning triggers (-3.1 s), and show consistency and accuracy of released data products using the MDC. This paper provides a performance overview for LVK low-latency alert structure and data products using the MDC in anticipation of O4

    4-aminobutyrate aminotrasferase (ABAT): genetic and pharmacological evidence for an involvement in gastro esophageal reflux disease

    Get PDF
    Extent: 9p.Gastro-esophageal reflux disease (GERD) is partly caused by genetic factors. The underlying susceptibility genes are currently unknown, with the exception of COL3A1. We used three independent GERD patient cohorts to identify GERD susceptibility genes. Thirty-six families, demonstrating dominant transmission of GERD were subjected to whole genome microsatellite genotyping and linkage analysis. Five linked regions were identified. Two families shared a linked region (LOD 3.9 and 2.0) on chromosome 16. We used two additional independent GERD patient cohorts, one consisting of 219 trios (affected child with parents) and the other an adult GERD case control cohort consisting of 256 cases and 485 controls, to validate individual genes in the linked region through association analysis. Sixty six single nucleotide polymorphism (SNP) markers distributed over the nine genes present in the linked region were genotyped in the independent GERD trio cohort. Transmission disequilibrium test analysis followed by multiple testing adjustments revealed a significant genetic association for one SNP located in an intron of the gene 4-aminobutyrate aminotransferase (ABAT) (Padj = 0.027). This association did not replicate in the adult case-control cohort, possibly due to the differences in ethnicity between the cohorts. Finally, using the selective ABAT inhibitor vigabatrin (c-vinyl GABA) in a dog study, we were able to show a reduction of transient lower esophageal sphincter relaxations (TLESRs) by 57.3611.4 % (p = 0.007) and the reflux events from 3.160.4 to 0.860.4 (p = 0.007). Our results demonstrate the direct involvement of ABAT in pathways affecting lower esophageal sphincter (LES) control and identifies ABAT as a genetic risk factor for GERD.Johan Jirholt, Bengt Åsling, Paul Hammond, Geoffrey Davidson, Mikael Knutsson, Anna Walentinsson, Jörgen M. Jensen, Anders Lehmann, Lars Agreus and Maria Lagerström-Ferme

    THE CONCISE GUIDE TO PHARMACOLOGY 2021/22: G protein-coupled receptors

    Get PDF
    The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/bph.15538. G protein-coupled receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2021, and supersedes data presented in the 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate

    THE CONCISE GUIDE TO PHARMACOLOGY 2019/20 : G protein- coupled receptors

    Get PDF
    The Concise Guide to PHARMACOLOGY 2019/20 is the fourth in this series of biennial publications. The Concise Guide provides concise overviews of the key properties of nearly 1800 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide represents approximately 400 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.14748. G protein-coupled receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2019, and supersedes data presented in the 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the International Union of Basic and Clinical Pharmacology Committee on Receptor Nomenclature and Drug Classification (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.Peer reviewe
    • 

    corecore