Using Competition Assays to Assess Dormancy: Effects of Gene Knockouts on Growth in Micrococcus luteus

Dormancy is a survival growth state some bacteria enter under stressful environmental conditions, such as nutrient deprivation. Dormancy is characterized by a severe decrease in metabolic activity where bacteria become viable but not culturable (VBNC), which is measurable by plating and counting colony forming units (CFU). This decrease in metabolic activity also reduces the effectiveness of antibiotics as they are less able to enter cells. For this reason, understanding the mechanism of initiating, sustaining, and resuscitating bacterial dormancy is critical for improving treatment of bacterial pathogens utilizing dormancy to evade antibiotic treatment. Competition experiments can measure the relative fitness of bacterial populations by co culturing the two (or more) populations and allowing them to compete for the same resources. My goal was to use a simple competition assay to measure the relative fitness of wild-type Micrococcus luteus to gene knockout strains of genes suspected in the mechanism of dormancy, such as the uspA616 gene. First I demonstrated that the pigment synthesis gene, crtE, in M. luteus is a neutral site in both nutrient rich and nutrient poor media. Knockout of the crtE gene ([delta] crtE::kan) produced white bacterial colonies, as opposed to yellow colonies in wild-type M. luteus. The [delta] crtE::kan bacterial strain was found to have similar fitness to wild-type and was therefore used as an easily identifiable wild-type substitute in all other competition experiments. With the white [delta] crtE::kan M. luteus strain I then show that the UspA616 gene knockout ([delta] uspA616::kan) strain has similar fitness to wild-type M. luteus in nutrient rich media, but is significantly less fit in nutrient poor media.Biology and Biochemistry, Department ofHonors Colleg

Equity valuation of Hugo Boss AG

The purpose of this dissertation is to evaluate the fair price per share of the German premium apparel manufacturer Hugo Boss AG and issue a buy, hold or sell recommendation. The valuation will take into account the current macroeconomic environment, several industry outlooks and trends, the company’s historical financial performance and its future strategy. Hugo Boss is evaluated by the intrinsic Discounted Cash Flow method, and complemented by the relative method of Multiples. Thus, a fair value between €81.15/share to €87.86/share is issued. This reflects an upside of 29.84% to 40.57% compared to the traded price of €62.50/share and concludes a buy recommendation.O objetivo desta dissertação é avaliar o “fair value” por ação do produtor Alemão de roupas premium Hugo Boss AG e emitir uma recomendação para “comprar, manter ou vender”. A avaliação da empresa terá em conta o ambiente macroeconómico atual, várias perspetivas e tendências do setor, o desempenho financeiro histórico da empresa e a sua futura estratégia. Hugo Boss é avaliada pelo método de Fluxo de Caixa Descontado intrínseco e complementado pelo método de Múltiplos relativo. Assim, um justo valor entre €81.15/ação e €87.86/ação é emitido. Isto reflete um aumento de 29.84% para 40.57% em relação ao preço negociado de €62.50/ação e conclui uma recomendação de “compra”

A Mixed-methods Study on Female Landowner Estate Planning Objectives

The majority of the forested land in New England is owned by private landowners, a large number of whom are at or above retirement age. In the coming decades these landowners are going to be making decisions about what happens to their land once they no longer own it. Female landowners specifically play a critical role in the long-term planning and decision-making process. Women generally have a longer life expectancy than men and assess their level of confidence and financial stability in ways that differ from men. This difference in perception influences the decisions they make about their land. Despite this, little is known about decisions female landowners are making and barriers they face to formulating informed decisions that are in line with their goals. In order to understand more about female landowners’ estate planning objectives, I conducted a mixed-methods study. Through a mail survey and subsequent qualitative interviews, I found that women were more likely than men to have lower confidence confidence in moving forward with plans for the land, lower certainty that their financial resources were adequate to move forward, and less certainty when it came to future decisions about their land. However, women who were certain about their estate planning objectives were more likely than men to have a conservation-based decision. The results of this mixed-methods study are applied to peer-to-peer network events and outcomes are discussed

Reduktion in natürlicher Sprache

Natural (conversational) speech, compared to cannonical speech, is earmarked by the tremendous amount of variation that often leads to a massive change in pronunciation. Despite many attempts to explain and theorize the variability in conversational speech, its unique characteristics have not played a significant role in linguistic modeling. One of the reasons for variation in natural speech lies in a tendency of speakers to reduce speech, which may drastically alter the phonetic shape of words. Despite the massive loss of information due to reduction, listeners are often able to understand conversational speech even in the presence of background noise. This dissertation investigates two reduction processes, namely regressive place assimilation across word boundaries, and massive reduction and provides novel data from the analyses of speech corpora combined with experimental results from perception studies to reach a better understanding of how humans handle natural speech. The successes and failures of two models dealing with data from natural speech are presented: The FUL-model (Featurally Underspecified Lexicon, Lahiri & Reetz, 2002), and X-MOD (an episodic model, Johnson, 1997). Based on different assumptions, both models make different predictions for the two types of reduction processes under investigation. This dissertation explores the nature and dynamics of these processes in speech production and discusses its consequences for speech perception. More specifically, data from analyses of running speech are presented investigating the amount of reduction that occurs in naturally spoken German. Concerning production, the corpus analysis of regressive place assimilation reveals that it is not an obligatory process. At the same time, there emerges a clear asymmetry: With only very few exceptions, only [coronal] segments undergo assimilation, [labial] and [dorsal] segments usually do not. Furthermore, there seem to be cases of complete neutralization where the underlying Place of Articulation feature has undergone complete assimilation to the Place of Articulation feature of the upcoming segment. Phonetic analyses further underpin these findings. Concerning deletions and massive reductions, the results clearly indicate that phonological rules in the classical generative tradition are not able to explain the reduction patterns attested in conversational speech. Overall, the analyses of deletion and massive reduction in natural speech did not exhibit clear-cut patterns. For a more in-depth examination of reduction factors, the case of final /t/ deletion is examined by means of a new corpus constructed for this purpose. The analysis of this corpus indicates that although phonological context plays an important role on the deletion of segments (i.e. /t/), this arises in the form of tendencies, not absolute conditions. This is true for other deletion processes, too. Concerning speech perception, a crucial part for both models under investigation (X-MOD and FUL) is how listeners handle reduced speech. Five experiments investigate the way reduced speech is perceived by human listeners. Results from two experiments show that regressive place assimilations can be treated as instances of complete neutralizations by German listeners. Concerning massively reduced words, the outcome of transcription and priming experiments suggest that such words are not acceptable candidates of the intended lexical items for listeners in the absence of their proper phrasal context. Overall, the abstractionist FUL-model is found to be superior in explaining the data. While at first sight, X-MOD deals with the production data more readily, FUL provides a better fit for the perception results. Another important finding concerns the role of phonology and phonetics in general. The results presented in this dissertation make a strong case for models, such as FUL, where phonology and phonetics operate at different levels of the mental lexicon, rather than being integrated into one. The findings suggest that phonetic variation is not part of the representation in the mental lexicon.Natürliche (spontane) Sprache in Dialogen zeichnet sich, im Vergleich zu kanonischer Sprache, vor allem durch das enorme Ausmaß an Variation aus. Diese kann oft dazu führen, dass Wörter in der Aussprache massiv verändert werden. Trotz einiger Bemühungen, Variabilität in natürlicher Sprache zu erklären und theoretisch zu fassen, haben die einzigartigen Merkmale natürlicher Sprache kaum Eingang in linguistische Modelle gefunden. Einer der Gründe, warum Variation in natürlicher Sprache zu beobachten ist, liegt in der Tendenz der Sprecher, Sprache zu reduzieren. Dies kann die phonetische Gestalt von Wörtern drastisch beeinflussen. Obwohl hierdurch massiv Information durch Reduktion verloren geht, sind Hörer oft in der Lage Spontansprache zu verstehen, sogar, wenn Hintergrundgeräusche dies erschweren. Diese Dissertation untersucht zwei Reduktionsprozesse: Regressive Assimilation des Artikulationsortes über Wortgrenzen hinweg und Massive Reduktion. Es werden neue Daten präsentiert, die durch die Analysen von Sprachkorpora gewonnen wurden. Außerdem stehen experimentelle Ergebnisse von Perzeptionsstudien im Mittelpunkt, die helfen sollen, besser zu verstehen, wie Menschen mit natürlicher Sprache umgehen. Die Dissertation zeigt die Erfolge und Probleme von zwei Modellen im Umgang mit Daten von natürlicher Sprache auf: Das FUL-Modell (Featurally Underspecified Lexicon , Lahiri & Reetz, 2002), und X-MOD (ein episodisches Modell, Johnson, 1997). Aufgrund unterschiedlicher Annahmen machen die zwei Modelle verschiedene Vorhersagen für die beiden Reduktionsprozesse, die in dieser Dissertation untersucht werden. Es werden Art und Auswirkungen der beiden Prozesse für Sprachproduktion untersucht und die Konsequenzen für das Sprachverstehen beleuchtet. Was die Sprachproduktion betrifft, so zeigt eine Korpusanalyse von natürlich gesprochenem Deutsch, dass der Reduktionsprozess regressive Assimilation des Artikulationsortes nicht obligatorisch statt findet. Gleichzeitig wird eine hervorstechende Asymmetrie deutlich: Abgesehen von einigen wenigen Ausnahmen werden ausschließlich [koronale] Segmente assimiliert, [labiale] und [dorsale] Segmente normalerweise nicht. Außerdem, so legen die Produktionsdaten nahe, gibt es Fälle, in denen die Assimilation des Artikulationsortes an den Artikulationsort des Folgesegmentes komplett ist, also eine vollständige Neutralisierung der Merkmalskontraste vom Sprecher vorgenommen wurde. Phonetische Analysen bestätigen dieses Resultat. Im Fall von Löschungen und massiven Reduktion demonstrieren die Ergebnisse eindeutig, dass phonologische Regeln – im klassischen generativen Sinne – nicht in der Lage sind, die Reduktionsmuster zu beschreiben, die in Spontansprache vorkommen. Alles in allem zeigen die Analysen von massiven Reduktionen und Löschungen keine eindeutigen Muster auf. Um einzelne Faktoren, die Reduktionen beeinflussen, genauer untersuchen zu können, wurde die Löschung von (Wort) finalem /t/ anhand eines neuen, für diesen Zweck kreierten Korpus durchgeführt. Die Analyse dieses Korpus unterstreicht, dass, obwohl phonologischer Kontext eine gewichtigen Einfluss darauf hat, ob Segmente (d.h. /t/) gelöscht werden, dieser Einfluss eher als Tendenz verstanden werden muss, nicht als absolute Bedingung. Dieses Resultat trifft auch auf andere Löschungsprozesse zu. Beide Modelle (X-MOD und FUL), die in dieser Dissertation untersucht werden, gehen im Kern der Frage nach, wie Hörer Sprache verstehen. Fünf Experimente untersuchen, wie reduzierte Sprache von menschlichen Hörern wahrgenommen wird. Ergebnisse von zwei Studien zeigen, dass Assimilationen von deutschen Hörern durchaus als komplett neutralisiert wahrgenommen werden. Was die Perzeption von massiv reduzierten Wörtern betrifft, belegen die Resultate von Transkriptionsstudien und Priming-Experimenten, dass solche Wörter nicht als Wortkandidaten für die korrekten lexikalischen Einträge akzeptiert werden, wenn sie ohne ihren Satz-Kontext dargeboten werden. Insgesamt ist das abstraktionistische FUL-Modell besser in der Lage, die Daten zu erklären, die in dieser Dissertation präsentiert werden. Auf den ersten Blick scheint X-MOD zwar etwas besser geeignet, die Produktionsdaten zu erklären, hauptsächlich jedoch, weil Variation als Grundannahme im Modell verankert ist. FUL ist klar überlegen, was die Perzeptionsseite betrifft. Ein weiteres wichtiges Ergebnis dieser Dissertation ist die Rolle, die Phonologie und Phonetik im Allgemeinen zugedacht werden kann. Die Resultate, die hier vorgestellt werden, liefern starke Argumente für Modelle – wie z.B. FUL – in denen Phonologie und Phonetik auf verschiedenen Ebenen des mentalen Lexikons aktiv sind und nicht in einem integriert sind. Die Befunde legen nahe, dass phonetische Variation nicht Teil der Repräsentation im mentalen Lexikon ist