96 research outputs found

    La Chimaphile ombellée (Chimaphila umbellata) en Hesse

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    Das ehemals in Süd- und Osthessen in Kiefernanbaugebieten weiter verbreitete Dolden-Winterlieb (Chimaphila umbellata) hat nach dramatischen Bestandesrückgängen in dem schon seit Jahrhunderten bekannten Verbreitungsgebiet in den Sandgebieten Südhessens heute nur noch wenige Restbestände im Bereich zwischen Niederroden, Zellhausen und Babenhausen in der östlichen Untermainebene. Ursache des Rückgangs waren sowohl Änderungen der Waldstruktur als auch die Schädigung der für die Entwicklung und Nährstoffversorgung der Winterlieb-Pflanzen unbedingt notwendigen Mykorrhiza-Pilze durch die Stickstoff-Immissionen im ausgehenden 20. Jahrhundert. Durch wenige Schutzmaßnahmen können die verbliebenen hessischen Vorkommen, die inzwischen zu den westlichsten in Europa gehören, zumindest vor mechanischen Beeinträchtigungen bewahrt werden. Wichtig wäre aber auch weitere Forschung zum noch nicht völlig geklärten Themenkomplex Chimaphila-Mykorrhiza-Baum, also die Bindung der Chimaphila-Pflanzen an einen oder mehrere Bäume in der Umgebung.The Prince’s Pine (Chimaphila umbellata) was once widespread in the pine forests of southern and eastern Hesse, but is now confined to a few stands in the eastern Main valley between Niederroden, Zellhausen, and Babenhausen. These stands now represent the western limit in Europe. The causes of this dramatic decline include changes in forestry practices and nitrogen immissions in the late 20th century, which affected the mycorrhizae of this species. Preventive measures can be taken to safeguard these remaining stands from mechanical damage. Further research is needed on the depen-dencies between Chimaphila, its mycorrhizae, and the surrounding forest.La Chimaphile ombellée (Chimaphila umbellata), autrefois présente dans les régions du Sud et de l’Est de la Hesse qui sont plantées de conifères, n’a plus que quelques populations qui subsistent dans la région de Niederroden, Zellhausen et Babenhau-sen dans la plaine inférieure orientale du Main, du fait de leur recul dramatique sur les surfaces sablonneuses du sud de la Hesse où elles étaient répandues depuis des siècles. La raison de cette disparition en est aussi bien les changements survenus dans la structure de la forêt que la dégradation, par les émissions d’azote à la fin du 20ème siècle, des champignons mycorhiziens nécessaires à son développement et à l’apport en substances nutritives. Quelques mesures de protection pourraient permettre de sauver du moins des interventions mécaniques les quelques populations en Hesse, les plus occidentales en Europe. Il serait important également d’explorer le rôle de la mycorhize pour la chimaphile, c.à.d. de sa liaison à une ou plusieurs espèces d’arbres voisins

    Significance of patient categorization for perioperative management of children with tetralogy of Fallot, with special regard to co-existing malformations

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    Background: The aim of our study was to facilitate perioperative calculation of potential risk factors on the outcome of corrective surgery for children with tetralogy of Fallot. Methods: The medical records of 81 (44 female and 37 male) out of a total of 87 patients undergoing complete surgical repair of tetralogy of Fallot between 1988 and 2004 at the Children’s Hospital of the Johannes Gutenberg University of Mainz were reviewed. Patients were divided into four categories, depending on the severity of pulmonary stenosis and cyanosis, as well as on the type of pulmonary circulation. Results: Additional malformations did not affect mortality rates, but did directly affect the number of pleural effusions, time of epinephrine administration, duration of surgery, bypass, and ischemia, as well as length of hospitalization and intensive care unit treatment. In contrast to longer periods of extracorporeal circulation and ischemia during surgery, which are directly related not only to more complex anatomical situations but also to higher mortality and complication rates, the much-debated question of age at surgery had no influence either on the surgical approach itself or on the post-operative outcome. Conclusions: Our patient categorization, and evaluation of potential pre-operative risk factors and intraoperative parameters, should prove useful for the future planning and execution of therapeutic procedures in institutions around the world. (Cardiol J 2010; 17, 1: 20-28

    ITIH5 mediates epigenetic reprogramming of breast cancer cells

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    Extracellular matrix (ECM) is known to maintain epithelial integrity. In carcinogenesis ECM degradation triggers metastasis by controlling migration and differentiation including cancer stem cell (CSC) characteristics. The ECM-modulator inter- α-trypsin inhibitor heavy chain family member five (ITIH5) was recently identified as tumor suppressor potentially involved in impairing breast cancer progression but molecular mechanisms underlying its function are still elusive

    “Dogged” Search of Fresh Nakhla Surfaces Reveals New Alteration Textures

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    Special Issue: 74th Annual Meeting of the Meteoritical Society, August 8-12, 2011, London, U.K.International audienceCarbonaceous chondrites are considered as amongst the most primitive Solar System samples available. One of their primitive characteristics is their enrichment in volatile elements.This includes hydrogen, which is present in hydrated and hydroxylated minerals. More precisely, the mineralogy is expected to be dominated by phyllosilicates in the case of CM chondrites, and by Montmorillonite type clays in the case of CI. Here, in order to characterize and quantify the abundance of lowtemperature minerals in carbonaceous chondrites, we performed thermogravimetric analysis of matrix fragments of Tagish Lake, Murchison and Orgueil

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Combinations of single-top-quark production cross-section measurements and vertical bar f(LV)V(tb)vertical bar determinations at root s=7 and 8 TeV with the ATLAS and CMS experiments

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    This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb(-1) at = 7 TeV and 12.2 to 20.3 fb(-1) at = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 +/- 5.7 pb and 87.7 +/- 5.8 pb at = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 +/- 4.1 pb and 23.1 +/- 3.6 pb at = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 +/- 1.4 pb at = 8 TeV. The square of the magnitude of the CKM matrix element V-tb multiplied by a form factor f(LV) is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V-td|, |V-ts| << |V-tb|. All the |f(LV)V(tb)|(2) determinations, extracted from individual ratios at = 7 and 8 TeV, are combined, resulting in |f(LV)V(tb)| = 1.02 +/- 0.04 (meas.) +/- 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.Peer reviewe

    Measurements of top-quark pair differential cross-sections in the eμe\mu channel in pppp collisions at s=13\sqrt{s} = 13 TeV using the ATLAS detector

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    Search for single production of vector-like quarks decaying into Wb in pp collisions at s=8\sqrt{s} = 8 TeV with the ATLAS detector

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    Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at s=8TeV\sqrt{s}=8\,\mathrm TeV{} with the ATLAS detector

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