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Innovations in cancer treatment have lowered mortality, but little is known about their economic benefits. We assess the effect of two decades of improvements in cancer treatment options on the labor market outcomes of breast and prostate cancer patients. In addition, we compare this effect across cancer patients with different levels of educational attainment. We estimate the effect of medical innovation on cancer patients' labor market outcomes employing tax return and cancer registry data from Canada and measuring medical innovation by using the number of approved drugs and a quality-adjusted patent index. While cancer patients are less likely to work after their diagnosis, we find that the innovations in cancer treatment during the 1990s and 2000s reduced the negative employment effects of cancer by 63-70 percent. These benefits of medical innovation are limited to cancer patients with postsecondary education, raising concerns about unequal access to improved treatment options.

To assist the design of novel, highly efficient molecular junctions, a deep understanding of the precise charge transport mechanisms through these devices is of prime importance. In the present contribution, we describe a procedure to investigate spatially-resolved electron transport through a nanojunction from first principles, at the example of a nitro-substituted oligo-(phenylene ethynylene) covalently bound to graphene nanoribbon leads. Recently, we demonstrated that the conductivity of this single-molecule-graphene-nanoribbon junction can be switched quantitatively and reversibly upon application of a static electric field in a top gate position, in the spirit of a traditional field effect transistor [J. Phys. Chem. C, 2016, 120, 28808-28819]. The propensity of the central oligomer unit to align with the external field was found to induce a damped rotational motion and to cause an interruption of the conjugated $\pi$-system, thereby drastically reducing the conductance through the nanojunction. In the current work, we use the driven Liouville-von-Neumann (DLvN) approach for time-dependent electronic transport calculations to simulate the electronic current dynamics under time-dependent potential biases for the two logical states of the nanojunction. Our quantum dynamical simulations rely on a novel localization procedure using an orthonormal set of molecular orbitals obtained from a standard density functional theory calculation to generate a localized representation for the different parts of the molecular junction. The transparent DLvN formalism allows us to directly access the density matrix and to reconstruct the time-dependent electronic current density, unraveling unique mechanistic details of the electron transport.

In this contribution, we extend our framework for analyzing and visualizing correlated many-electron dynamics to non-variational, highly scalable electronic structure method. Specifically, an explicitly time-dependent electronic wave packet is written as a linear combination of $N$-electron wave functions at the configuration interaction singles (CIS) level, which are obtained from a reference time-dependent density functional theory (TDDFT) calculation. The procedure is implemented in the open-source Python program detCI@ORBKIT, which extends the capabilities of our recently published post-processing toolbox [J. Comput. Chem. 37 (2016) 1511]. From the output of standard quantum chemistry packages using atom-centered Gaussian-type basis functions, the framework exploits the multi-determinental structure of the hybrid TDDFT/CIS wave packet to compute fundamental one-electron quantities such as difference electronic densities, transient electronic flux densities, and transition dipole moments. The hybrid scheme is benchmarked against wave function data for the laser-driven state selective excitation in LiH. It is shown that all features of the electron dynamics are in good quantitative agreement with the higher-level method provided a judicious choice of functional is made. Broadband excitation of a medium-sized organic chromophore further demonstrates the scalability of the method. In addition, the time-dependent flux densities unravel the mechanistic details of the simulated charge migration process at a glance.

The analysis and visualization of electron dynamics in molecular systems represents an effective means to gain deeper understanding of various physical and chemical processes. For this purpose, this theoretical-chemical dissertation aims at the development of general analysis tools (detCI@ORBKIT) and new theoretical methods (“Born-Oppenheimer Broken Symmetry” ansatz), focusing on the different components of the electronic continuity equation. This fundamental relation connects the electron density with the electronic flux density, or electronic current density. While the former is a scalar field, which defines the probability distribution of the electrons, the latter is a vector field describing the instantaneous and spatially resolved flow of electrons. The robustness and scalability of the developed methodological framework is first benchmarked, before it is subsequently applied to various fields. In chemistry, curved arrows are drawn at Lewis structures to symbolize the electron movement during chemical reactions. In the first application, this simple model is elucidated by means of quantum dynamics exemplary for the benzene molecule. For this purpose, different localized electronic superposition states are prepared by laser excitation initiating charge migration in the attosecond time regime. The analysis of the time evolution of the electron density reveals that, in the investigated cases, the electrons follow a pincer-type mechanism and that, in contrast to the predictions by the simple traditional model, a very small number of electrons is transported. Interestingly, the laser preparation phase is observed to play an important role in the patterns of charge migration. The last part of this dissertation is devoted to electron dynamics in a graphene-based molecular nanojunction. By applying dissipative quantum dynamics, it is demonstrated that this nanostructure can be reliably switched by a static electric field in the spirit of a traditional field effect transistor. The subsequent investigation of the electronic flux density for both conformers yields an intuitive picture of the charge migration mechanism and reveals a possible route to optimize the structure of the nanojunction. The main conclusions of my doctoral studies can be summarized as follows: While the analysis of the electron density allows quantitative statements about reaction mechanisms, the electronic flux density gives a direct and intuitive insight into the exact course of chemical reactions. The gained dynamical information not only significantly contributes to the understanding of chemical mechanisms, but can also help to optimize the functionality of the devices under investigation., Die Analyse und Visualisierung von Elektronendynamik in molekularen Systemen stellt ein effektives Mittel dar, um ein tiefer gehendes Verständnis über verschiedenste physikalische und chemische Prozesse zu gewinnen. Um dies zu ermöglichen, werden in dieser theoretisch-chemischen Doktorarbeit allgemeine Analysewerkzeuge (detCI@ORBKIT) und neue theoretische Methoden („Born- Oppenheimer Broken Symmetry“ Ansatz) erarbeitet. Dabei wird der Schwerpunkt auf die verschiedenen Komponenten der elektronischen Kontinuitätsgleichung gelegt. Diese fundamentale Gleichung verbindet das Skalarfeld der Elektronendichte, die die Aufenthaltswahrscheinlichkeit der Elektronen definiert, mit dem Vektorfeld der Elektronenflussdichte oder Elektronenstromdichte, welche den instantanen und ortsaufgelösten Elektronenfluss beschreibt. Der entwickelte methodische Rahmen wird zunächst auf seine Robustheit und Skalierbarkeit hin untersucht, bevor er anschließend produktiv in verschiedenen Bereichen eingesetzt wird. In der Chemie werden gebogenen Pfeile an Lewisstrukturen skizziert, um die Elektronenbewegung während chemischer Reaktionen zu symbolisieren. Im ersten Anwendungsbereich wird dieses einfache Modell mit quantendynamischen Mitteln am Beispiel des Benzolmoleküls näher beleuchtet. Mittels Laseranregung werden hierfür zunächst verschiedene lokalisierte elektronische Superpositionszustände erzeugt, was jeweils eine Ladungsmigration im Attosekundenbereich zur Folge hat. Analysen der Dynamik der Elektronendichte verdeutlichen, dass die Elektronen in den untersuchten Fällen einem zangenartigen Mechanismus folgen und dass wesentlich weniger Elektronen fließen als durch das einfache Modell vorhergesagt. Interessanterweise, wird beobachtet, dass die Laserpräparationsphase einen großen Einfluss auf die Flussmuster während der Ladungsmigration haben kann. Der letzte Teil dieser Dissertation widmet sich der Elektronendynamik in einem graphenbasierten molekularen Nanoschalter. Zunächst wird mittels dissipativer Quantendynamik demonstriert, dass die Nanostruktur ähnlich eines traditionellen Feldeffekttransistors durch ein statisches elektrisches Feld zuverlässig geschaltet werden kann. Die nachfolgende Untersuchung der Elektronenflussdichte in beiden Konformeren zeigt anschaulich den Ladungsmigrationsmechanismus und offenbart einen möglichen Optimierungsweg hinsichtlich der Struktur des Nanoschalters. Die Hauptaussagen meines Promotionsstudiums lassen sich folgendermaßen zusammenfassen: Während die Analyse der Elektronendichte quantitative Aussagen über Reaktionsmechanismen erlaubt, gibt die Elektronenflussdichte einen direkten und intuitiven Einblick in deren genaue Abläufe. Die gewonnenen dynamischen Informationen tragen nicht nur signifikant zum Verständnis der Mechanismen bei, sondern können auch dabei helfen die Funktionalität der untersuchten Geräte zu optimieren.

The Patient Protection and Affordable Care Act expands Medicaid and in-troduces health insurance subsidies, thereby changing work incentives for single mothers. To undertake an ex ante policy evaluation of the employment effects of the PPACA, I structurally estimate a model of labor supply and health in-surance choice exploiting existing variation in Medicaid policies. Simulations show that single mothers increase their labor supply at the extensive and the intensive margin by six and five percent, respectively. The PPACA leads to crowding-out of employer-sponsored health insurance of about 40 percent and increases single mothers' welfare by about $190 per month.