THE CREATION OF SLAVE CHRISTIANITY IN VIRGINIA, 1770-1850

This dissertation is a broad examination of black Baptist cultures within biracial churches in Virginia from the American Revolution until 1850, a time of intense growth in slave Christianity. When slaves converted in Virginia, most converted in, and became members of, biracial churches. These churches created new relationships between whites and blacks. The dissertation follows the efforts of black Baptists to construct their faith and their relationships within the constraints of churches that were controlled by their white male membership. My research reveals a fuller picture of biracial Baptist communities than scholars have previously constructed. Most slave members of Baptist churches were not owned by the whites in their churches. In addition, whites and slaves in Baptist churches usually did not live in the same places. Slaves were more likely to reside on larger plantations and whites to live on smaller farms. Slaves and whites in biracial churches were linked by complex geographic and social ties that cut across the boundaries of farms and plantations. Biracial churches could be sites of conflicts between white leaders and slaves who covertly resisted their efforts to use churches as methods of social control. They were also, however, the sites of conflicts among slaves over the meaning of conversion to evangelical Christianity. The dissertation brings to light the conflicts in slave communities caused by the growth of Christianity, involving issues such as marriage, divorce, and alcohol use. This project relies heavily on case studies of particular churches that illustrate broad themes, supplemented by chapters that use data drawn from diverse areas to explore particular dynamics. Baptist slaves did not passively accept Baptist fellowship and worship. Blacks begun to join Baptist churches in significant numbers at the same time as the church brought in many white converts. In this period of growth, slaves dramatically influenced Baptist worship. At the same time, they constructed a distinct form of Baptist Christianity. The dissertation concludes by looking at the black leaders of biracial churches who carved out their careers by acting as intermediaries between the white men who controlled biracial churches and slave members of these churches

Customer Centricity im digitalen Zeitalter : Handlungsempfehlungen zur Optimierung der kundenorientierten Unternehmensführung

Die vorliegende Bachelorarbeit untersucht die theoretischen Grundlagen zur Kundenorientierung von Unternehmen in Zeiten der digitalen Transformation und erläutert den Customer-Centricity-Ansatz. Das Ziel der Arbeit ist es, Handlungsempfehlungen für Unternehmen zu entwickeln, anhand derer sie ihre kundenorientierte Unternehmensführung optimieren können. Hierzu werden neben der Darstellung der theoretischen Grundlagen zwei Unternehmen beschrieben, welche den Customer-Centrictiy-Ansatz erfolgreich umgesetzt haben. Anschließend werden die Ansätze beider Unternehmen gegenübergestellt und Erfolgsfaktoren definiert.The master thesis examines the theoretical basics of the customer orientation of companies in times of digital transformation and explains the customer centricity approach. The aim of this work is to develope recommendations for companies to optimize their customeroriented corporate management. In addition to presenting the theoretical basics, two companies are described which have implemented the Customer Centric approach succesfully. Subsequently, the approaches of both companies are compared and success factors are defined

Biochemische Charakterisierung und physiologische Bedeutung eines neuen durch Typ I Interferon induzierten Gens

In der vorliegenden Arbeit wurden Struktur, Expression und Regulation des Interferon-regulierten-Gens-28 (IFRG28) untersucht und das Protein anhand von selbst hergestellten monoklonalen Antikörpern und stabil-transfizierten Zelllinien biochemisch und funktionell charakterisiert. Als IFN-spezifische Kontrollelemente konnten in der proximalen Promotorregion drei Interferon-Stimulierte-Response-Elemente (ISRE) und mehrere GAS- (Gamma-Aktivierte-Sequenz) Motive identifiziert werden, deren Einfluss auf die Induzierbarkeit des IFRG28-Promotors mit Hilfe von Deletionskonstrukten in Reporergenassays untersucht wurde. Die Analyse ergab, dass die Aktivität der untersuchten Promotorregion in den ISRE begründet liegt. Um den individuellen Einfluss jedes der drei Motive auf die Transkription überprüfen zu können, wurden Punktmutationen in die einzelnen Elemente eingeführt. Die sequentielle Inaktivierung aller drei Motive zeigte, dass jedes ISRE allein funktionell ist, obwohl individuelle Unterschiede in ihrer Aktivität festgestellt wurden. Für die biochemische Charakterisierung wurde das Protein heterolog in Bakterien exprimiert und als aufgereinigtes GST-Fusionsprotein einer Sprague Dawley Ratte zur Herstellung von monoklonalen Antikörpern injiziert. Nach Zellfusion und anschließendem Screening konnten 18 Hybridome identifiziert werden, von denen 17 ein spezifisches Signal im Western-Blot und in der Immunpräzipitation zeigten. Mit Hilfe der gewonnen Antikörper konnte nachgewiesen werden, dass IFRG28 sehr schnell durch IFN induziert wird, eine lange biologische Halbwertszeit von mehr als 8 h besitzt und sehr wahrscheinlich in vesikukären Strukturen lokalisiert ist. Zur Aufklärung einer möglichen Funktion wurden Zelllinien mit stabiler IFRG28-Expression hergestellt und auf eine veränderte Zellphysiologie nach Transgenexpression untersucht. Es stellte sich heraus, dass IFRG28 die zytopathischen Effekte einer Infektion mit Encephalomyocarditis-Virus (EMCV) und Vesicular-Stomatitis-Virus (VSV) hinauszögert. Dieser Nachweis konnte an zwei verschiedenen Zelllinien erbracht werden, womit sichergestellt ist, dass die antivirale Aktivität kein Positionseffekt der integrierten DNA darstellt. Um den Zusammenhang einer antiviralen Wirkung mit der IFRG28-Expression näher zu prüfen, wurde die Replikation des EMCV in den konstitutiv exprimierenden Ba/F3 Zellen verfolgt. In diesen Versuchen konnte klar gezeigt werden, dass IFRG28 einen hemmenden Einfluss auf die virale Replikation ausübt

Versatile high power pulse-laser source for pico- and nanosecond optical pulses

This paper presents a pulse-laser source for the generation of ps and ns laser pulses with more than 50 W peak output power. The final stages of the drivers use GaN transistors and are capable of switching currents of 0.8 A with 200 ps minimum pulse width and 50 A with 3 ns minimum pulse width. The pulses can be externally triggered by ECL logic. Both single-pulse and pulse train modes are possible

Amplifications of picosecond laser pulses in tapered semiconductor amplifiers: Numerical simulations versus experiments

We apply a travelling wave model to the simulation of the amplification of laser pulses generated by Q-switched or mode-locked distributed-Bragg reflector lasers. The power amplifier monolithically integrates a ridge-waveguide section acting as pre-amplifier and a flared gain-region amplifier. The diffraction limited and spectral-narrow band pulses injected in to the pre-amplifier have durations between 10 ps and 100 ps and a peak power of typical 1 W. After the amplifier, the pulses reach a peak power of several tens of Watts preserving the spatial, spectral and temporal properties of the input pulse. We report results obtained by a numerical solution of the travelling-wave equations and compare them with experimental investigations. The peak powers obtained experimentally are in good agreement with the theoretical predictions. The performance of the power amplifier is evaluated by considering the dependence of the pulse energy as a function of different device and material parameters

A recoil detector for the measurement of antiproton-proton elastic scattering at angles close to 90∘^{\circ}

The design and construction of a recoil detector for the measurement of recoil protons of antiproton-proton elastic scattering at scattering angles close to 90$^{\circ}$ are described. The performance of the recoil detector has been tested in the laboratory with radioactive sources and at COSY with proton beams by measuring proton-proton elastic scattering. The results of laboratory tests and commissioning with beam are presented. Excellent energy resolution and proper working performance of the recoil detector validate the conceptual design of the KOALA experiment at HESR to provide the cross section data needed to achieve a precise luminosity determination at the PANDA experiment.Comment: 10 pages, 15 figure

Anion-π catalysis: Bicyclic products with four contiguous stereogenic centers from otherwise elusive diastereospecific domino reactions on π-acidic surfaces

Anion–π interactions have been introduced recently to catalysis. The idea of stabilizing anionic intermediates and transition states on π-acidic surfaces is a new fundamental concept. By now, examples exist for asymmetric enolate, enamine, iminium and transamination chemistry, and the first anion–π enzyme has been created. Delocalized over large aromatic planes, anion–π interactions appear particularly attractive to stabilize extensive long-distance charge displacements during domino processes. Moving on from the formation of cyclohexane rings with five stereogenic centers in one step on a π-acidic surface, we here focus on asymmetric anion–π catalysis of domino reactions that afford bicyclic products with quaternary stereogenic centers. Catalyst screening includes a newly synthesized, better performing anion–π version of classical organocatalysts from cinchona alkaloids, and anion–π enzymes. We find stereoselectivities that are clearly better than the best ones reported with conventional catalysts, culminating in unprecedented diastereospecificity. Moreover, we describe achiral salts as supramolecular chirality enhancers and report the first artificial enzyme that operates in neutral water with anion–π interactions, i.e., interactions that are essentially new to enzymes. Evidence in support of contributions of anion–π interactions to asymmetric catalysis include increasing diastereo- and enantioselectivity with increasing rates, i.e., asymmetric transition-state stabilization in the presence of π-acidic surfaces and inhibition with the anion selectivity sequence NO3− > Br− > BF4− > PF6−

Ultrahigh-Throughput Screening of an Artificial Metalloenzyme using Double Emulsions

The potential for ultrahigh-throughput compartmentalization renders droplet microfluidics an attractive tool for the directed evolution of enzymes. Importantly, it ensures maintenance of the phenotype-genotype linkage throughout optimization, enabling reliable identification of improved mutants. The full potential of droplet microfluidics remains unexplored, however, as droplet sorting often relies on low-throughput, custom-made devices that typically only allow simultaneous analysis of two parameters. Here, we report an approach for ultrahigh-throughput screening of an artificial metalloenzyme in double emulsion droplets (DEs) using commercially-available fluorescence-activated cell sorters (FACS). This protocol was validated by screening a 400 double-mutant streptavidin library for ruthenium-catalyzed deallylation of allocprotected aminocoumarin. The most active variants, identified by next generation sequencing, were in good agreement with hits obtained using a 96-well plate procedure. These findings pave the way for the systematic implementation of FACS for the directed evolution of enzymes and will significantly expand the accessibility of ultrahighthroughput DE screening protocols