2,729 research outputs found

    Inclusive top pair production at Tevatron and LHC in electron/muon final states

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    Recent measurements of the inclusive top pair production at the Tevatron and LHC collider in the electron/muon final states are discussed. Measurements at the Tevatron use up to 9.7 /fb of data, and at the LHC up to 4.9 /fb of data at s=7\sqrt{s}=7 TeV and up to 20.3 /fb of data at s=8\sqrt{s}=8 TeV. For the experiments at both colliders these corresponds to the full data sets at the given center-of-mass energies. Overall results are in agreement between the experiments at the Tevatron and between the experiments at the LHC. All measurements are in agreement with recent theory calculations at NNLO QCD. Individual LHC measurements are challenging the precision of the theory calculations.Comment: Proceedings for the 6th International Workshop on Top Quark Physics. 14-19 September 2013, Durbach, German

    Measurement of the D* Meson Cross Section and Extraction of the Charm Contribution, F2c(x,Q2), to the Proton Structure in Deep Inelastic ep Scattering with the H1 Detector at HERA

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    Die Produktion von D*-Mesonen in tiefunelastischer Streuung bei HERA wurde mit Daten untersucht, die mit dem H1-Detektor in den Jahren 2004-2007 aufgezeichnet wurden. Diese Daten entsprechen einer integrierten LuminositĂ€t von 347 pb-1, welches eine Steigerung der verfĂŒgbaren Statistik um den Faktor acht, verglichen mit der vorherigen H1-Publikation, darstellt. Der sichtbare Bereich dieser Messung deckt PhotonvirtualitĂ€ten von 5 1,5 GeV in einem PseudorapiditĂ€tsbereich von |eta(D*)| < 1,5 gemessen. Einfach- und doppeltdifferentielle Verteilungen werden mit perturbativen QCD Vorhersagen in fĂŒhrender und nĂ€chstfĂŒhrender Ordnung verglichen. Der systematische Fehler der Messung ist entscheidet verringert worden. Der Beitrag von charm-Quarks zur Protonstruktur, F2c(x,Q2), wird in zwei verschiedenen QCD Evolutionsschemata aus den gemessenen D*-Meson Wirkungsquerschnitten bestimmt und mit pQCD Vorhersagen in nĂ€chst-fĂŒhrender Ordnung verglichen. Dabei wird eine, verglichen mit der letzten H1-Publikation, 18fach höhere Statistik genutzt. Die vorliegende Arbeit umfaßt ebenfalls ein erfolgreich beendetes Hardwareprojekt: Die Inbetriebnahme und Optimierung der dritten Stufe des schnellen Spurtriggers (FTT) bei H1, die Anfang 2006 erfolgreich abgeschlossen wurde. Der FTT ist in die ersten drei Stufen des zentralen H1-Triggersystems integriert und stellt eine verbesserte SelektivitĂ€t fĂŒr die Identifizierung von Ereignissen mit geladenen Teilchen zur VerfĂŒgung. Die dritte Stufe des FTT fĂŒhrt innerhalb von 100 Mikrosekunden eine spurbasierte Ereignisrekonstruktion aus und ist als Computerfarm, bestehend aus PowerPC Karten, realisiert. Außerdem wurde die FTT Simulation in die Simulation des H1-Triggersystems integriert

    Left Atrial Chamber and Appendage Function After Internal Atrial Defibrillation: A Prospective and Serial Transesophageal Echocardiographic Study

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    AbstractObjectives. The purpose of this prospective study was to assess left atrial chamber and appendage function after internal atrial defibrillation of atrial fibrillation and to evaluate the time course of recovery.Background. External cardioversion of atrial fibrillation may result in left atrial appendage dysfunction (“stunning”) and may promote thrombus formation. In contrast to external cardioversion, internal atrial defibrillation utilizes lower energies; however, it is unknown whether the use of lower energies may avoid stunning of the left atrial appendage.Methods. Transesophageal and transthoracic echocardiography were performed in 20 patients 24 h before and 1 and 7 days after internal atrial defibrillation to assess both left atrial chamber and appendage function. Transthoracic echocardiography was again performed 28 days after internal atrial defibrillation to assess left atrial function. The incidence and degree of spontaneous echo contrast accumulation (range 1+ to 4+) was noted, and peak emptying velocities of the left atrial appendage were measured before and after internal atrial defibrillation. To determine left atrial mechanical function, peak A wave velocities were obtained from transmitral flow velocity profiles.Results. Sinus rhythm was restored in all patients. The mean ± SD peak A wave velocities increased gradually after cardioversion, from 0.47 ± 0.16 m/s at 24 h to 0.61 ± 0.13 m/s after 7 days (p < 0.05) and 0.63 ± 0.13 m/s after 4 weeks. Peak emptying velocities of the left atrial appendage were 0.37 ± 0.16 m/s before internal atrial defibrillation, decreased significantly after internal atrial defibrillation to 0.23 ± 0.1 m/s at 24 h (p < 0.01) and then recovered to 0.49 ± 0.23 m/s (p < 0.01) after 7 days. The corresponding values for the degree of spontaneous echo contrast were 1.2 ± 1.2 before internal atrial defibrillation versus 2.0 ± 1.0 (p < 0.01) and 1.1 ± 1.3 (p < 0.01) 1 and 7 days after cardioversion, respectively. One patient developed a new thrombus in the left atrial appendage, and another had a thromboembolic event after internal atrial defibrillation.Conclusions. Internal atrial defibrillation causes depressed left atrial chamber and appendage function and may result in the subacute accumulation of spontaneous echo contrast and development of new thrombi after cardioversion. These findings have important clinical implications for anticoagulation therapy before and after low energy internal atrial defibrillation in patients with atrial fibrillation.(J Am Coll Cardiol 1997;29:131–8)

    Making Green Real – How to Promote Greenery in Real Estate Development

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    Climate change and rising temperatures particularly affect the built environment and intensify the Urban Heat Island (UHI) effect in cities. Nature-based solutions can have a balancing function and reduce overheating. However, greenery still receives too little attention in architecture and is added as an additional element at the end of the planning phase or even after the building has been constructed. For a climate resilient urban development in the future, in addition to a change in processes, a change in real estate development and in the project management is necessary. At least, three preconditions must be met for this to happen: ‱ Sound knowledge base: Many studies already exist proving the positive effects of nature-based solutions for densely built cities. However, the knowledge transfer to real estate companies is still insufficient as they require precise and site-specific information showing effectiveness of greenery on microclimate, building envelope and indoor temperature. At best, analyses apply a system view and consider interrelations with water and energy. ‱ Greenery-friendly planning framework: Real estate development takes place in compliance with local planning standards and procedures. Planning strategies and regulations, standards, urban development contracts and funding programmes strongly influence urban design and development and hereby have great potential to promote greening. ‱ Integrated mindset: In architecture and real estate development, it is still not standard to include greenery and nature-based solutions in design, planning and construction. Building optimization also includes greening. Thus, it needs an integrated mindset regarding greenery as natural part of architecture. This requires more awareness and knowledge about climate change and the benefits of nature-based solutions on quality of life and value of real estates in the long run. The paper summarizes the experience of an interdisciplinary cooperation in the research project GreenDeal4Real and addresses all three aspects in detail. Analyses of the planning framework in Vienna and impacts of greening measures on the microclimate are described and general conclusions for more green in real estate development are drawn

    Switch in KRAS mutational status during an unusual course of disease in a patient with advanced pancreatic adenocarcinoma: implications for translational research

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    Background: Despite the introduction of novel effective treatment regimens like gemcitabine plus nab-paclitaxel and FOLFIRINOX, pancreatic ductal adenocarcinoma (PDAC) remains one of the most aggressive epithelial tumors. Among the genetic alterations frequently found in PDAC, mutations in the KRAS gene might play a prognostic role regarding overall survival and may also have the potential to predict the efficacy of anti-EGFR treatment. Case presentation: We report the clinical case of a 69 year old Caucasian female that was diagnosed with histologically confirmed locally advanced PDAC with lymph node involvement in August 2010. At the time of first diagnosis, tumor tissue obtained from an open regional lymph node biopsy showed a poorly differentiated adenocarcinoma with a wild type sequence within exon 2 (codon 12/13) of the KRAS gene. The patient initially received single-agent gemcitabine and a subsequent 5-FU-based chemoradiotherapy with a sequential maintenance chemotherapy with oral capecitabine resulting in a long term disease control. Local disease progression occurred in May 2014 and the patient underwent pancreaticoduodenectomy in September 2014. A novel KRAS gene mutation (c. 35G > T, p. G12 V) in exon 2 (codon 12) was detected within the surgical specimen. As of January 2016 the patient is still alive and without evidence of the underlying disease. Conclusions: Specifically in the context of clinical trials and translational research in PDAC a re-assessment of molecular biomarkers, i.e. KRAS, at defined time points (e.g. relapse, disease progression, unusual clinical course) may be indicated in order to detect a potential switch in biomarker status during the course of disease

    How to use implantable loop recorders in clinical trials and hybrid therapy

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    Epidemiological studies show that atrial fibrillation (AF) is associated with a doubling of mortality, even after adjustment for confounders. AF can be asymptomatic, but this does not decrease the thromboembolic risk of the patient. Office ECGs, occasional 24-h Holter recordings and long-term ECG event recording might not be sensitive and accurate enough in patients with AF, especially in those with paroxysmal episodes. In one study, 7 days of continuous monitoring with event recorders detected paroxysmal AF in 20 of 65 patients with a previous negative 24-h Holter recording. Over the last decade, enormous improvements have been made in the technology of implantable devices, which can now store significant information regarding heart rhythm. The first subcutaneous implantable monitor (Reveal XT, Medtronic) was validated for continuous AF monitoring by the XPECT study. The dedicated AF detection algorithm uses irregularity and incoherence of R–R intervals to identify and classify patterns in ventricular conduction. Its sensitivity in identifying patients with AF is >96%. Numerous clinical data from continuous monitoring of AF have recently been published. The first applications of this technology have been in the field of surgical and catheter AF ablation. With regard to cryptogenic stroke, an international randomized trial is ongoing to compare standard care with standard care plus the implantable cardiac monitor for AF detection in patients discharged with the diagnosis of cryptogenic stroke: the Crystal AF trial. Continuous AF monitoring provides an optimal picture of daily AF burden, both symptomatic and asymptomatic. Implantable cardiac monitors have high sensitivity, enable better assessment of therapy success and may guide further AF therapy

    SDC4Lit – Infrastruktur, Methodik und Kompetenzvermittlung fĂŒr einen Datenlebenszyklus Digitaler Literatur

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    Digitale Literatur ist aufgrund ihrer MedialitĂ€t und Ästhetik ein besonderer Gegenstand. Mit Digitaler Literatur sind dabei nicht digitalisierte Texte gemeint, die vorher oder auch primĂ€r als gedruckte Texte produziert und in die Distribution gebracht werden, sondern genuin digitale Formate. In SDC4Lit gehören dazu Werke der Netzliteratur, literarische Blogs und Computerspiele. Die besondere Ästhetik und MedialitĂ€t digitaler Literatur erfordern je spezifische AnsĂ€tze im archivarischen und forschungsorientierten Umgang. Die Dimension des Digitalen im Umgang mit diesen Born-digitals ist dabei eine zentrale, aber nicht die einzige Dimension, sodass neue literarische Formen auch innovative AnsĂ€tze im Umgang mit neuen Datentypen erfordern. Neue Lösungen fĂŒr die Archivierung und Bereitstellung von digitalen Objekten sind nötig. Es reicht nicht aus, historische digitale Texte nur zu speichern, sondern es mĂŒssen Mechanismen und Methoden fĂŒr die Rekonstruktion, Wiedergabe und Analyse dieser Texte vorhanden sein. Mit diesem Poster wird das Science Data Center fĂŒr Literatur (SDC4Lit) vorgestellt. Das Zentrum ist mit dem Ziel entstanden, die Anforderungen, die Digitale Literatur an ihre Archivierung, Erforschung und Vermittlung stellt, systematisch zu reflektieren und entsprechende Lösungen fĂŒr einen nachhaltigen Datenlebenszyklus fĂŒr Literaturforschung und - vermittlung langfristig umzusetzen. Im Zuge dessen ist ein langzeitverfĂŒgbares Repositorium fĂŒr Digitale Literatur entstanden. Das Repositorium dient als zentraler Speicher fĂŒr verschiedene gesammelte Formen von Digitaler Literatur, sowie daraus abgeleitete Derivate, insbesondere Text- und Netzwerkstrukturdaten, als Grundlage fĂŒr weitere Analysen. Die interdisziplinĂ€re Zusammenarbeit im Projekt verbindet Expertisen aus den Bereichen Archiv, Literaturwissenschaft, Höchstleistungsrechnen, Maschinelle Sprachverarbeitung und Digital Humanities. Diese Kooperation erlaubt dem Zentrum, eine Infrastruktur anzubieten und das erarbeitete Know-How und Erfahrungen mit Nutzer*innen zu teilen. Neben den fĂŒr die Analyse angebotenen Daten bietet das Zentrum mehrere Anleitungen an, wie mit den BestĂ€nden des Repositoriums gearbeitet werden kann. Die entwickelte Infrastruktur zusammen mit dazugehörigem Wissen zu Analysemethoden und Tools erlauben die UnterstĂŒtzung aller notwendigen Arbeiten in einem nachhaltigen Datenlebenszyklus Digitaler Literatur