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In this thesis, a layered X-ray backlighter target with front side modifications for optimal laser target coupling is developed. The testing of this novel target design was done at the PHELIX laser system, located at the GSI Helmholtzzentrum für Schwerionenforschung GmbH in Darmstadt. This dissertation was carried out within the laser and plasma physics group of the Institut für Kernphysik at the Technische Universität Darmstadt. X-ray radiation is an invaluable tool for the diagnosis of high energy density (HED) experiments. Strong X-ray emission can be generated, among other things, through the irradiation of solid-state targets by high-energy short-pulse lasers with intensities above 10^18 W cm^−2. The resulting photon flux is in the order of 10^10 - 10^11 ph J^−1 within a narrow spectral bandwidth. The possible applications of such a source include radiography and scattering studies of dense plasmas in order to determine key thermodynamic variables like temperature or density. Two types of X-ray backlighter sources are commonly used, which can be differentiated by the degree of ionization of the emitting material. For weak ionization, the spectrum is very similar to the characteristic X-ray line emission and is called Kα radiation. With rising ionization the energy of the X-rays increases as well, leading to thermal line emission for highly ionized sources. However, thermal line emission cannot be produced efficiently with laser driven backlighters for photon energies beyond 10 keV, as more and more electrons have to be ionized from the heavier elements. Therefore, for high energy line emission, a laser-driven Kα source is preferred. Within the scope of this thesis, a novel laser driven Kα source was developed and successfully tested. The goal was two-fold. Primarily, an improvement of the energy transfer from laser into target to increase the number of emitted Kα photons should be achieved. In order to fulfil this goal, front side modifications in form of cone-like microstructures were used. Secondly, a thermal isolation of the emitting material from the laser plasma interaction region should be achieved. This produces a clean spectrum without any additional thermal line emission. This was done by constructing the target from two layers, namely the aforementioned front side modifications and a back side layer of different material for the X-ray emission. The performance of the developed target was studied in an experiment with the PHELIX laser system. The observed spectra from the layered target displayed a successful suppression of thermal line emission, displaying the effective thermal isolation. This result is further supported with a spectroscopic line shape analysis to determine the mean electron temperature within the emitting material. Temperatures of 31 - 42 eV were found, indicating a weak ionization without involvement of the two inner-most electron shells. The total number of Kα photons were measured to be in the order of 10^10 ph J^−1. A clear increase of factor 2 - 3 in Kα photons due to the microstructures on the front side was demonstrated. The source size of the targets were determined to be 140 - 200 μm. The orientation of the cone-like microstructures with respect to the laser were varied as well and displayed a clear influence on the Kα yield and source size. For a parallel alignment, the highest photon flux of 3.9 × 10^11 ph J^−1 mm^−2 was found. Atomic radiative simulations were successfully used to determine the electron temperature in the backside layer to 31 - 42 eV. Another unique feature of the layered target design is the possibility to influence the source size through the shape of the back side layer. The source size was successfully reduced to 100 μm using a circular shaped back side layers of the same dimensions. With these targets it was also possible to demonstrate the possibility of generating two spatially separated, distinct sources from one target.

Introduction Recent data suggest that margins ≥2 mm after breast-conserving surgery may improve local control in invasive breast cancer (BC). By allowing large resection volumes, oncoplastic breast-conserving surgery (OBCII; Clough level II/Tübingen 5-6) may achieve better local control than conventional breast conserving surgery (BCS; Tübingen 1-2) or oncoplastic breast conservation with low resection volumes (OBCI; Clough level I/Tübingen 3-4). Methods Data from consecutive high-risk BC patients treated in 15 centers from the Oncoplastic Breast Consortium (OPBC) network, between January 2010 and December 2013, were retrospectively reviewed. Results A total of 3,177 women were included, 30% of whom were treated with OBC (OBCI n = 663; OBCII n = 297). The BCS/OBCI group had significantly smaller tumors and smaller resection margins compared with OBCII (pT1: 50% vs. 37%, p = 0.002; proportion with margin p < 0.001). There were significantly more re-excisions due to R1 (“ink on tumor”) in the BCS/OBCI compared with the OBCII group (11% vs. 7%, p = 0.049). Univariate and multivariable regression analysis adjusted for tumor biology, tumor size, radiotherapy, and systemic treatment demonstrated no differences in local, regional, or distant recurrence-free or overall survival between the two groups. Conclusions Large resection volumes in oncoplastic surgery increases the distance from cancer cells to the margin of the specimen and reduces reexcision rates significantly. With OBCII larger tumors are resected with similar local, regional and distant recurrence-free as well as overall survival rates as BCS/OBCI.

Hintergrund: Um eine optimale Krebsversorgung von Lungenkrebspatienten entsprechend der medizinischen Leitlinien zu sichern, finden in zertifizierten Krebszentren interdisziplinäre Tumorkonferenzen statt. Durch die Bündelung der Expertise verschiedener medizinischer Fachbereiche soll hier [zum vollständigen Text gelangen Sie über die oben angegebene URL], 17. Deutscher Kongress für Versorgungsforschung (DKVF)

Einleitung: Über das konkrete Ausmaß einer Neck-Dissection während der totalen Laryngektomie gibt es weder national noch international einen offiziellen Konsens in Form von Leitlinien. Dies hat einen individuellen und nicht-standardisierten Therapieplan in der chirurgischen Therapie des Halses beim fortgeschrittenen Larynxkarzinom zur Folge. Methoden: Wir untersuchten retrospektiv die Verläufe von 58 konsekutiven Patienten, die sich an der Charité wegen eines fortgeschrittenen Plattenepithelkarzinoms des Larynx einer totalen Laryngektomie mit beidseitiger Neck-Dissection unterzogen. Hierbei wurde zum einen das Nodal Yield des ipsilateralen Halses bzgl. Auswirkung auf Overall und Disease-free Survival untersucht. Zum anderen etablierten wir ein Klassifikationsschema des CT-basierten Mittelllinienbezugs des Primärtumors (Typ A „clear“, B „involved“, C „exceeded“ und D „bilateral“) und untersuchten die Relation zu kontralateraler Halslymphknoten-Metastasierung. Ergebnisse: Uni- und multivariate Regresssionsanalysen zeigten keinen signifikanten Einfluss des ipsilateralen Nodal Yields auf Overall- und Disease-free Survival (p < 0.05). Ein pN+-Hals zeigte einen negativen prognostischen Wert (OS: hazard ratio [HR] 0.179; p=0,013). In 10,3% zeigte sich ein p2Nc-Hals. Typ-D-tumoren haben eine Wahrscheinlichkeit von 23,5% kontralateral zu metastasieren. Typ-A-Tumoren unterliegen einer Risiko-Reduktion von 100% für kontralaterale Metastasierung. Schlussfolgerungen: Das ipsilaterale Nodal Yield einer Neck-Dissection in der Laryngektomie hat keinen Einfluss auf das Outcome. Bei Typ-A-Tumoren und klinisch unauffälligem kontralateralen Hals (≤ cN2b) scheint eine kontralaterale Neck-Dissection nicht indiziert, was zur Reduktion von OP-Zeit und Komplikationsraten beitragen kann. Der Erstautor gibt keinen Interessenkonflikt an., GMS Current Posters in Otorhinolaryngology - Head and Neck Surgery; 13:Doc238

Einleitung: Das angemessene Ausmaß der Neck dissection (ND) in der Therapie von Kopf-Hals-Karzinomen ist weiterhin Gegenstand wissenschaftlichen Interesses. Ziel dieser Studie war es, herauszufinden, ob die Lymphknotenausbeute (nodal yield, NY) von NDs bei laryngektomierten Patienten einen prognostischen[zum vollständigen Text gelangen Sie über die oben angegebene URL], 87. Jahresversammlung der Deutschen Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie