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The PhD addresses the feasibility of reconstructing open charm mesons with the Compressed Baryonic Matter experiment, which will be installed at the FAIR accelerator complex at Darmstadt/Germany. The measurements will be carried out by means of a dedicated Micro Vertex Detector (MVD), which will be equipped with CMOS Monolithic Active Pixel Sensors (MAPS). The feasibility of reconstructing the particles with a proposed detector setup was studied.
To obtain conclusive results, the properties of a MAPS prototype were measured in a beam test at the CERN-SPS accelerator. Based on the results achieved, a dedicated simulation software for the sensors was developed and implemented into the software framework of CBM (CBMRoot). Simulations on the reconstruction of D0-mesons were carried out. It is concluded that the reconstruction of those particles is possible.
The PhD introduces the physics motivation of doing open charm measurements, represents the results of the measurements of MAPS and introduces the innovative simulation model for those sensors as much as the concept and results of simulations of the D0 reconstruction.
Ziel: Nebennierenraumforderungen können sonographisch mit guter Sensitivität und Spezifität erkannt werden. Ziel der vorliegenden Studie war es, die Wertig-keit der Kontrastmittel-Sonographie (CEUS = contrast enhanced ultrasound) unter Verwendung von Zeit-Intensitäts-Kurven für die Charakterisierung von Nebennierenraumforderungen zu bewerten.
Material und Methoden: 108 Patienten mit 116 Raumforderungen der Neben-niere erhielten einen Ultraschall der Nebenniere, inklusive einer Kontrastmittel-Sonographie mit dem Kontrastmittel SonoVue®. Die Kontrastmitteldynamik wurde mittels Zeit-Intensitätskurven aufgezeichnet. Anhand der Kontrastmittel-anflutungszeit wurden folgende vier Kontrastmittelanreicherungsmuster ver-wendet, welche in einer Pilotstudie1 entwickelt wurden: Anreicherungsmuster I = früh arterielle Kontrastmittelanreicherung, Anreicherungsmuster II = arterielle Kontrastmittelanreicherung, Anreicherungsmuster III = späte Kontrastmittelan-reicherung, Anreicherungsmuster IV = keine Kontrastmittelanreicherung. Zu-sätzlich erhielten alle Patienten eine Beurteilung der Nebenniere durch ein zweite Bildgebendes Verfahren (Computertomographie (CT) oder Magnetresonanztomographie (MRT)) sowie eine laborchemische Hormondiagnostik. In Fällen mit malignitätsverdächtigem Befund erfolgte eine Biopsie oder Adrenalektomie.
Ergebnisse: CEUS- Anreicherungsmuster I und II konnten bei allen Patienten mit primärem oder sekundärem Malignom der Nebenniere (n = 16) nachgewie-sen werden. Die Sensitivität der CEUS für die Diagnose einer malignen Neben-nierenraumforderung betrug 100% (95% CI [75; 100]) und die Spezifität 67% (95% CI [56; 75]). Bei 40 Nebennierenraumforderungen war die Histologie die Referenzmethode. In 68% dieser Nebennierenraumforderungen waren MRT/CT und CEUS kongruent in der Beurteilung der Dignität. Schlussfolgerung: Die Kontrastmittel-Sonographie ist eine nützliche ergän-zende Methode in der Aufarbeitung von Nebennierenraumforderungen mit exzellenter Sensitivität für die Diagnose eines Malignoms.
Most elements heavier than iron are synthesized in stars during neutron capture reactions in the r- and s-process. The s-process nucleosynthesis is composed of the main and weak component. While the s-process is considered to be well understood, further investigations using nucleosynthesis simulations rely on measured neutron capture cross sections as crucial input parameters. Neutron capture cross sections
relevant for the s-process can be measured using various experimental methods. A prominent example is the activation method relying on the 7Li(p,n)7Be reaction as a neutron source, which has the advantage of high neutron intensities and is able to create a quasi-stellar neutron spectrum at kBT = 25 keV. Other neutron sources able to provide quasi-stellar spectra at different energies suffer from lower neutron intensities. Simulations using the PINO tool suggest the neutron activation of samples with different neutron spectra, provided by the 7Li(p,n)7Be reaction, and a subsequent linear combination of the obtained spectrum-averaged cross sections
to determine the Maxwellian-averaged cross section (MACS) at various energies of astrophysical relevance. To investigate the accuracy of the PINO tool at proton energies between the neutron emission threshold at Ep = 1880.4 keV and 2800 keV,
measurements of the 7Li(p,n)7Be neutron fields are presented, which were carried out at the PTB Ion Accelerator Facility at the Physikalisch-Technische Bundesanstalt in Braunschweig. The neutron fields of ten different proton energies were measured.
The presented neutron fields show a good agreement at proton energies Ep = 1887, 1897, 1907, 1912 and 2100 keV. For the other proton energies, E p = 2000, 2200, 2300, 2500, and 2800 keV, differences between measurement and simulation were found and discussed. The obtained results can be used to benchmark and adapt the PINO tool and provide crucial information for further improvement of the neutron activation method for astrophysics.
An application for the 7Li(p,n)7Be neutron fields is presented as an activation experiment campaign of gallium, an element that is mostly produced during the weak s-process in massive stars. The available cross section data for the 69,71Ga(n,γ)
reactions, mostly determined by activation measurements, show differences up toa factor of three. To improve the data situation, activation measurements were carried out using the 7Li(p,n)7Be reaction. The neutron capture cross sections for
a quasi-stellar neutron spectrum at kBT = 25 keV were determined for 69Ga and 71Ga.
In this dissertation the formal abstraction and verification of analog circuit is examined. An approach is introduced that automatically abstracts a transistor level circuit with full Spice accuracy into a hybrid automaton (HA) in various output languages. The generated behavioral model exhibits a significant simulation speed-up compared to the original netlist, while maintaining an acceptable accuracy, and can be therefore used in various verification and validation routines. On top of that, the generated models can be formally verified against their Spice netlists, making the obtained models correct by construction.
The generated abstract models can be extended to enclose modeling as well as technology dependent parameter variations with little over approximations. As these models enclose the various behaviors of the sampled netlists, the obtained models are of significant importance as they can replace several simulations with just a single reachability analysis or symbolic simulation. Moreover, these models can be as well be used in different verification routines as demonstrated in this dissertation.
As the obtained models are described by HAs with linear behaviors in the locations, the abstract models can be as well compositionally linked, allowing thereby the abstraction of complex analog circuits.
Depending on the specified modeling settings, including for example the number of locations of the HA and the description of the system behavior, the accuracy, speedup, and various additional properties of the HA can be influenced. This is examined in detail in this dissertation. The underlying abstraction process is first covered in detail. Several extensions are then handled including the modeling of the HAs with parameter variations. The obtained models are then verified using various verification methodologies. The accuracy and speed-up of the abstraction methodology is finally evaluated on several transistor level circuits ranging from simple operational amplifiers up to a complex circuits.
Intelligenz ist einer der stärksten Einzelprädikatoren für berufliche Leistungen. Hochintelligente Personen, sogenannte Hochbegabte, müssten daher generell hohe berufliche Leistungen erbringen. Dies steht jedoch im Widerspruch zu Darstellungen von Schwierigkeiten Hochbegabter im Beruf. Sollten die negativen Stereotype zutreffen, wäre dies aus ressourcenorientierter Sicht problematisch, da Organisationen das der Hochbegabung zugrunde liegende Potenzial der Mitarbeiter*innen nicht hinreichend nutzen. Die vorliegende Arbeit leistet einen Beitrag dazu, diese Diskrepanz aufzuklären, indem sie untersucht wie Hochbegabte ihre berufliche Situation (erfolgreich) gestalten. Nach einer Begriffsklärung und Darstellung des Zusammenhangs von Intelligenz und Beruf wird im ersten Beitrag der internationale Forschungsstand mithilfe eines Literature Reviews systematisiert. Aufbauend darauf werden im zweiten Beitrag mithilfe einer Fragebogenerhebung die überwiegend internationalen Beiträge durch eine deutsche Stichprobe und die bisher wenig betrachtete Gruppe von Hochbegabten gemäß Kompetenzdefinition ergänzt. Schließlich fokussiert der dritte Beitrag den Widerspruch, dass Hochbegabte generell erfolgreich und zufrieden im Beruf sind, jedoch individuell von Schwierigkeiten berichten. Dazu werden teilstrukturierte Interviews durchgeführt, um ein tieferes Verständnis für den Einfluss der Hochbegabung auf den Beruf sowie etwaige bestehende Unterschiede zu nicht-hochbegabten Personen zu gewinnen. Zudem werden Strategien erfasst, die Hochbegabte nutzen, um Unterschiede und eventuell daraus resultierende Schwierigkeiten zu bewältigen. Abschließend werden Implikationen für die Berufspraxis und Forschung diskutiert.
Mast cells are long-lived tissue-resident leukocytes, located most abundantly in the skin and mucosal surfaces. They belong to the first line of defence of the body, protecting against invading pathogens, toxins and allergens. Their secretory granules are densely packed with a plethora of mediators, which can be released immediately upon activation of the cell. Next to their role in IgE-mediated allergic diseases and in promoting inflammation, potential anti-inflammatory functions have been assigned to mast cells, depending on the biological setting. The aim of this thesis was to contribute to a better understanding of the role of mast cells during the resolution of a local inflammation. Therefore, in a first of step a suitable model of a local inflammation had to be identified. Since comparison of the two Toll-like receptor (TLR)-agonists zymosan and lipopolysaccharide (LPS), which are most commonly used to locally induce inflammation, revealed a systemic response after LPS-injection and a local inflammation after zymosan-injection, the TLR2 agonist zymosan was chosen for the subsequent experiments. Multi epitope ligand cartography (MELC) combined with statistical neighbourhood analysis showed that mast cells are located in an anti-inflammatory microenvironment next to M2 macrophages during resolution of inflammation, while neutrophils and M1 macrophages are located in the zymosan-filled core of the inflammation. Furthermore, infiltrating neutrophils during peak inflammation and an increasing population of macrophages phagocytosing neutrophils during resolution of inflammation could be observed. MELC as well as flow cytometry analysis of mast cell-deficient mice revealed a decreased phagocytosing activity of macrophages in the absence of mast cells. As an untargeted approach to identify mast cell-derived mediators induced by zymosan, mRNA sequencing of bone marrow-derived mast cells (BMMCs) was performed. Gene ontology term analysis of the sequencing data revealed the induction of the type I interferon (IFN) pathway as the dominant response. Contradicting previous studies, I could validate the production of IFN-β by mast cells in response to zymosan and LPS in vitro. Furthermore IFN-β expression by mast cells was also detected in vivo. In accordance with previous studies regarding other cell types the release of IFN-β by mast cells depends on endosomal signaling. The potential of IFN-β to enhance the phagocytosing activity of macrophages has been demonstrated recently. Besides IFN-β, various other mediators with reported enhancing effects on macrophage phagocytosis were also induced by zymosan in BMMCs, including Interleukin (IL)-1β, IL-4, IL-13, and Prostaglandin (PG) E2. Thus, either one of these mediators alone or a combination of them could promote macrophage phagocytosis.
In conclusion, I herein present mast cells as a novel source for IFN-β induced by non-viral TLR ligands and demonstrate their enhancing effect on macrophage phagocytosis, thereby contributing to the resolution of inflammation.