67 research outputs found

    Beeinflussung der generativen Vermehrung von Rumex obtusifolius durch produktionstechnische Maßnahmen

    Get PDF
    Rumex obtusifolius produces a large number of long living seeds. Therefore, all means to reduce seed production or establishment of seedlings from seeds are impor-tant. The data of this paper show that in grassland a high soil seed bank not necessar-ily leads to a high infestation with dock. There are options to interfere seed production and establishment of seedlings. The cutting regime may have an impact on seed production. Establishment of seedlings can be minimized by avoiding gaps in the vegetation canopy

    Postoperative elective pelvic nodal irradiation compared to prostate bed irradiation in locally advanced prostate cancer – a retrospective analysis of dose-escalated patients

    Get PDF
    Background: It is uncertain if whole-pelvic irradiation (WPRT) in addition to dose-escalated prostate bed irradiation (PBRT) improves biochemical progression-free survival (bPFS) after prostatectomy for locally advanced tumors. This study was initiated to analyze if WPRT is associated with bPFS in a patient cohort with dose-escalated (> 70 Gy) PBRT. Methods: Patients with locally advanced, node-negative prostate carcinoma who had PBRT with or without WPRT after prostatectomy between 2009 and 2017 were retrospectively analyzed. A simultaneous integrated boost with equivalent-doses-in-2-Gy-fractions (EQD-2) of 79.29 Gy or 71.43 Gy to the prostate bed was applied in patients with margin-positive (or detectable) and margin-negative/undetectable tumors, respectively. WPRT (44 Gy) was offered to patients at an increased risk of lymph node metastases. Results: Forty-three patients with PBRT/WPRT and 77 with PBRT-only were identified. Baseline imbalances included shorter surgery-radiotherapy intervals (S-RT-Intervals) and fewer resected lymph nodes in the WPRT group. WPRT was significantly associated with better bPFS in univariate (p = 0.032) and multivariate models (HR = 0.484, p = 0.015). Subgroup analysis indicated a benefit of WPRT (p = 0.029) in patients treated with rising PSA values who mostly had negative margins (74.1%); WPRT was not associated with a longer bPFS in the postoperative setting with almost exclusively positive margins (96.8%). Conclusion: We observed a longer bPFS after WPRT compared to PBRT in patients with locally advanced prostate carcinoma who underwent dose-escalated radiotherapy. In subset analyses, the association was only observed in patients with rising PSA values but not in patients with non-salvage postoperative radiotherapy for positive margins

    A Mouse Model of Pulmonary Metastasis from Spontaneous Osteosarcoma Monitored In Vivo by Luciferase Imaging

    Get PDF
    BACKGROUND: Osteosarcoma (OSA) is lethal when metastatic after chemotherapy and/or surgical treatment. Thus animal models are necessary to study the OSA metastatic spread and to validate novel therapies able to control the systemic disease. We report the development of a syngeneic (Balb/c) murine OSA model, using a cell line derived from a spontaneous murine tumor. METHODOLOGY: The tumorigenic and metastatic ability of OSA cell lines were assayed after orthotopic injection in mice distal femur. Expression profiling was carried out to characterize the parental and metastatic cell lines. Cells from metastases were propagated and engineered to express Luciferase, in order to follow metastases in vivo. PRINCIPAL FINDINGS: Luciferase bioluminescence allowed to monitor the primary tumor growth and revealed the appearance of spontaneous pulmonary metastases. In vivo assays showed that metastasis is a stable property of metastatic OSA cell lines after both propagation in culture and luciferase trasduction. When compared to parental cell line, both unmodified and genetically marked metastatic cells, showed comparable and stable differential expression of the enpp4, pfn2 and prkcd genes, already associated to the metastatic phenotype in human cancer. CONCLUSIONS: This OSA animal model faithfully recapitulates some of the most important features of the human malignancy, such as lung metastatization. Moreover, the non-invasive imaging allows monitoring the tumor progression in living mice. A great asset of this model is the metastatic phenotype, which is a stable property, not modifiable after genetic manipulation

    Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

    Full text link
    A measurement of the cosmic-ray spectrum for energies exceeding 4×10184{\times}10^{18} eV is presented, which is based on the analysis of showers with zenith angles greater than 6060^{\circ} detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×10185.3{\times}10^{18} eV, the "ankle", the flux can be described by a power law EγE^{-\gamma} with index γ=2.70±0.02(stat)±0.1(sys)\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)} followed by a smooth suppression region. For the energy (EsE_\text{s}) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25(stat)1.2+1.0(sys))×1019E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19} eV.Comment: Replaced with published version. Added journal reference and DO

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

    Full text link
    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

    Full text link
    We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

    Mantle earthquakes beneath Fogo volcano, Cape Verde: Evidence for subcrustal fracturing induced by magmatic injection

    Full text link
    Highlights • Subcrustal earthquakes detected beneath Fogo volcano, Cape Verde. • At the focal depth of 40 km temperatures are likely too high for brittle failure. • The earthquakes may originate from magma injection into a deep subcrustal reservoir. • This observation indicates a distinct magma supply system of Fogo volcano. Abstract Fogo volcano belongs to the Cape Verde hotspot and its most recent eruption occurred from November 2014 to February 2015. From January to December 2016 we operated a temporary seismic network and array on Fogo and were able to locate 289 earthquakes in total. Array analysis shows that most of the events occur within the crust at distances >25 km near the neighboring island of Brava. However, on 15th August 2016 the network recorded an isolated cluster of >20 earthquakes, 13 of which could be located beneath the southern part of Fogo. The differences between S- and P-wave arrival times at steep incidence clearly indicate focal depths between approximately 38 and 44 km whereas receiver-function analyses place the Moho discontinuity at depths between 11 and 14 km. Thus, the earthquakes are located well within the upper mantle directly beneath Fogo. In view of the elevated upper-mantle temperatures within a hotspot regime, we propose that fracturing induced by magmatic injection is the most likely cause for the observed deep earthquakes

    Holz-Beton-Verbünde mit konduktiv erwärmter Schnellklebetechnik

    Get PDF
    Innovationen im Bauwesen zielen häufig auf Kostenreduktion durch Materialeinsparung mit neuen Materialkombinationen und schnellerem Baufortschritt durch hohen Vorfertigungsgrad. Weiterhin kommen dem zunehmenden Wunsch nach Nutzung nachwachsender Rohstoffe im Bauwesen insbesondere Holz-basierte Bauweisen entgegen, die schon seit langem im Fertighausbau für kleinere Gebäude wie 1- und 2-Familienhäuser am Markt verfügbar sind. Da reine Holzbauweisen jedoch für größere Gebäude auf verschiedene Hindernisse stoßen, sind sinnvolle Materialkombinationen mit etablierten Baustoffen des Hochbaus eine Lösuttg. Holz-Beton-Verbünde können in häufig verwendeten Bauelement-Bereichen wie Zwischendecken oder Dächern ihre Eigenschaften günstig kombinieren und werden bisher üblicherweise entweder mit zahlreichen mechanischen Verbindungsmitteln (lange Schrauben) oder durch Verguss von Frischbeton auf Holz realisiert. Eine neuartige Schnellklebetechnik (erstmals untersucht für den Fertighausbau) vermeidet verschiedene Nachteile und ermöglicht Kleben im Hochbau mit beheizter Klebefuge. Strukturelle Klebstoffe können so schneller aushärten und ermöglichen einen beschleunigten Baufortschritt im Vergleich zu konventionell kalthärtenden Klebungen. Die Beheizung der Klebefuge wird dabei durch einen dünnen elektrisch leitfähigen Klebebandträger realisiert, der als Strom durchflossener linearer Widerstand kontrolliert erwärmt werden kann. In einem laufenden Forschungsprojekt der Industriellen Gemeinschafts-Forschung (IGF) wird diese Schnellbautechnik für den Einsatz auf der Baustelle von Hochbauten untersucht. Der Beitrag stellt die klebtechnischen Herausforderungen an verschiedene Konstruktionsklebstoffe speziell an den Grenzflächen der sehr unterschiedlichen Werkstoffe wie Beton, Nadel- oder Laubholz sowie metallischen Klebebandträgem dar
    corecore