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DNA methylation, through 5-methyl- and 5-hydroxymethylcytosine (5mC and 5hmC) is considered to be one of the principal interfaces between the genome and our environment and it helps explain phenotypic variations in human populations. Initial reports of large differences in methylation level in genomic regulatory regions, coupled with clear gene expression data in both imprinted genes and malignant diseases provided easily dissected molecular mechanisms for switching genes on or off. However, a more subtle process is becoming evident, where small (<10%) changes to intermediate methylation levels were associated with complex disease phenotypes. This has resulted in two clear methylation paradigms. The latter "subtle change" paradigm is rapidly becoming the epigenetic hallmark of complex disease phenotypes, although we were currently hampered by a lack of data addressing the true biological significance and meaning of these small differences. The initial expectation of rapidly identifying mechanisms linking environmental exposure to a disease phenotype led to numerous observational/association studies being performed. Although this expectation remains unmet, there is now a growing body of literature on specific genes, suggesting wide ranging transcriptional and translational consequences of such subtle methylation changes. Data from the glucocorticoid receptor (NR3C1) has shown that a complex interplay between DNA methylation, extensive 5"UTR splicing and microvariability gives rise to the overall level and relative distribution of total and N-terminal protein isoforms generated. Additionally, the presence of multiple AUG translation initiation codons throughout the complete, processed, mRNA enables translation variability, hereby enhancing the translational isoforms and the resulting protein isoform diversity; providing a clear link between small changes in DNA methylation and significant changes in protein isoforms and cellular locations. Methylation changes in the NR3C1 CpG island, alters the NR3C1 transcription and eventually protein isoforms in the tissues, resulting in subtle but visible physiological variability. Implying external environmental stimuli act through subtle methylation changes, with transcriptional microvariability as the underlying mechanism, to fine-tune the total NR3C1 protein levels. The ubiquitous distribution of genes with similar structure as NR3C1, combined with an increasing number of studies linking subtle methylation changes in specific genes with wide ranging transcriptional and translational consequences, suggested a more genome-wide spread of subtle DNA methylation changes and transcription variability. The subtle methylation paradigm and the biological relevance of such changes were supported by two epigenetic animal models, which linked small methylation changes to either psychopathological or immunological effects. The first model, rats subjected to maternal deprivation, showed long term behavioural and stress response changes. A second model, exposing mice to early life infection with H1N1, illustrated long-term immunological effects. Both models displayed subtle changes within the methylome. Suggesting/Indicating that early life adversity and early life viral infection "programmed" the CNS and innate immune response respectively, via subtle DNA methylation changes genome-wide. The research presented in this thesis investigated the ever-growing roles of DNA methylation; the physiological and functional relevance of subtle small DNA methylation changes genome-wide, in particular for the CNS (MD model) and the immune system (early life viral infection model) ; and the evidence available, particularly from the glucocorticoid of the cascade of events initiated by such subtle methylation changes, as well as addressing the underlying question as to what represents a genuine biologically significant difference in methylation.
Zeugen die ein Tatgeschehen nicht beobachtet, sondern nur auditiv wahrgenommen haben, werden als Ohrenzeugen bezeichnet. Im Rahmen des Strafverfahrens erhalten Ohrenzeugen die Aufgabe, die Täterstimme im Rahmen einer akustischen Wahlgegenüberstellung (Voice Line-up) wiederzuerkennen. Die forensische Praxis zeigt, dass Ohrenzeugen diese Aufgabe unterschiedlich gut bewältigen können, ohne dass sich ein klares Muster erkennen lässt. In der Ohrenzeugenforschung gibt es jedoch Hinweise, dass musikalische Ausbildung die Fähigkeit zur Sprechererkennung verbessert.
Ziel dieser Arbeit ist es zu prüfen, ob das Ausmaß musikalischer Wahrnehmungskompetenz eine Prognose der Sprechererkennungsleistung erlaubt.
Um dies zu prüfen, nahmen 60 Versuchspersonen sowohl an einem „Musikalitätstest“ in Form der Montreal Battery for the Evaluation of Amusia (MBEA) als auch an einem target present Voice Line-up teil. Mittels Regressionsmodellen konnte bestimmt werden, dass die Wahrscheinlichkeit für eine korrekte Sprechererkennung steigt, je höher das Testergebnis der MBEA ausfällt. Dieses Testergebnis ermöglicht eine signifikante Prognose der Sprechererkennungsleistung. Die ebenfalls mittels Fragebögen erhobene Dauer der musikalischen Ausbildung erlaubt hingegen keine signifikante Prognose. Das durchgeführte Experiment zeigt auch, dass die Dauer der musikalischen Ausbildung das Testergebnis im Musikalitätstest nur eingeschränkt erklärt.
Diese Beobachtungen führen zu dem Schluss, dass bei einer Bewertung von Ohrenzeugen ein direktes Testen von musikalischer Wahrnehmungsfähigkeit einer Inferenz auf der Basis musik-biografischer Angaben vorzuziehen ist.
Flexibility and spatial mobility of labour are central characteristics of modern societies which contribute not only to higher overall economic growth but also to a reduction of interregional employment disparities. For these reasons, there is the political will in many countries to expand labour market areas, resulting especially in an overall increase in commuting. The picture of the various, unintended long-term consequences of commuting on individuals is, however, relatively unclear. Therefore, in recent years, the journey to work has gained high attention especially in the study of health and well-being. Empirical analyses based on longitudinal as well as European data on how commuting may affect health and well-being are nevertheless rare. The principle aim of this thesis is, thus, to address this question with regard to Germany using data from the Socio-Economic Panel. Chapter 2 empirically investigates the causal impact of commuting on absence from work due to sickness-related reasons. Whereas an exogenous change in commuting distance does not affect the number of absence days of those individuals who commute short distances to work, it increases the number of absence days of those employees who commute middle (25 " 49 kilometres) or long distances (50 kilometres and more). Moreover, our results highlight that commuting may deteriorate an individual- health. However, this effect is not sufficient to explain the observed impact of commuting on absence from work. Chapter 3 explores the relationship between commuting distance and height-adjusted weight and sheds some light on the mechanisms through which commuting might affect individual body weight. We find no evidence that commuting leads to excess weight. Compensating health behaviour of commuters, especially healthy dietary habits, could explain the non-relationship of commuting and height-adjusted weight. In Chapter 4, a multivariate probit approach is used to estimate recursive systems of equations for commuting and health-related behaviours. Controlling for potential endogeneity of commuting, the results show that long distance commutes significantly decrease the propensity to engage in health-related activities. Furthermore, unobservable individual heterogeneity can influence both the decision to commute and healthy lifestyle choices. Chapter 5 investigates the relationship between commuting and several cognitive and affective components of subjective well-being. The results suggest that commuting is related to lower levels of satisfaction with family life and leisure time which can largely be ascribed to changes in daily time use patterns, influenced by the work commute.
Entrepreneurship is a process of discovering and exploiting opportunities, during which two crucial milestones emerge: in the very beginning when entrepreneurs start their businesses, and in the end when they determine the future of the business. This dissertation examines the establishment and exit of newly created as well as of acquired firms, in particular the behavior and performance of entrepreneurs at these two important stages of entrepreneurship. The first part of the dissertation investigates the impact of characteristics at the individual and at the firm level on an entrepreneur- selection of entry modes across new venture start-up and business takeover. The second part of the dissertation compares firm performance across different entrepreneurship entry modes and then examines management succession issues that family firm owners have to confront. This study has four main findings. First, previous work experience in small firms, same sector experience, and management experience affect an entrepreneur- choice of entry modes. Second, the choice of entry mode for hybrid entrepreneurs is associated with their characteristics, such as occupational experience, level of education, and gender, as well as with the characteristics of their firms, such as location. Third, business takeovers survive longer than new venture start-ups, and both entry modes have different survival determinants. Fourth, the family firm- decision of recruiting a family or a nonfamily manager is not only determined by a manager- abilities, but also by the relationship between the firm- economic and non-economic goals and the measurability of these goals. The findings of this study extend our knowledge on entrepreneurship entry modes by showing that new venture start-ups and business takeovers are two distinct entrepreneurship entry modes in terms of their founders" profiles, their survival rates and survival determinants. Moreover, this study contributes to the literature on top management hiring in family firms: it establishes family firm- non-economic goals as another factor that impacts the family firm- hiring decision between a family and a nonfamily manager.
Gegenstand der vorliegenden Arbeit ist die Untersuchung der Lexik der spätmittelalterlichen Luxemburger Rechnungsbücher unter der Prämisse der Urbanität. Da auf keine ausgearbeitete Methodik zurückgegriffen werden konnte, anhand derer eine Einteilung in für die Analyse relevante bzw. irrelevante Lexik vorgenommen werden konnte, wurde im Rahmen der Arbeit unter Rückgriff auf sprachwissenschaftliche und geschichtswissenschaftliche Konzepte eine eigene Methodik entwickelt. Auf deren Basis erfolgte die Anlage des Untersuchungskorpus' auf der Grundlage der von 1388-1500 fast lückenlos überlieferten Rechnungsbücher der Stadt Luxemburg mit dem Ziel der Analyse spezifisch urbaner Lexik. Bei der Analyse wurde schließlich eine dreifache Zielsetzung verfolgt: Einerseits die Untersuchung der Lexik mit Blick auf die Verteilung von types und tokens in als spezifisch urban definierten Domänen, andererseits die Anlage eines Glossars, das als textphilologisches Werkzeug als Hilfsmittel bei der Erschließung der Rechnungsbücher dienen soll. Daneben wurde ebenfalls auf die geschichtswissenschaftlichen Erkenntnisgewinne eingegangen, die durch die jeweilige Wortschatzanalyse realisiert werden konnten.
Why do some people become entrepreneurs while others stay in paid employment? Searching for a distinctive set of entrepreneurial skills that matches the profile of the entrepreneurial task, Lazear introduced a theoretical model featuring skill variety for entrepreneurs. He argues that because entrepreneurs perform many different tasks, they should be multi-skilled in various areas. First, this dissertation provides the reader with an overview of previous relevant research results on skill variety with regard to entrepreneurship. The majority of the studies discussed focus on the effects of skill variety. Most studies come to the conclusion that skill variety mainly affects the decision to become self-employed. Skill variety also favors entrepreneurial intentions. Less clear are the results with regard to the influence of skill variety on the entrepreneurial success. Measured on the basis of income and survival of the company, a negative or U-shaped correlation is shown. Within the empirical part of this dissertation three research goals are tackled. First, this dissertation investigates whether a variety of early interests and activities in adolescence predicts subsequent variety in skills and knowledge. Second, the determinants of skill variety and variety of early interests and activities are investigated. Third, skill variety is tested as a mediator of the gender gap in entrepreneurial intentions. This dissertation employs structural equation modeling (SEM) using longitudinal data collected over ten years from Finnish secondary school students aged 16 to 26. As indicator for skill variety the number of functional areas in which the participant had prior educational or work experience is used. The results of the study suggest that a variety of early interests and activities lead to skill variety, which in turn leads to entrepreneurial intentions. Furthermore, the study shows that an early variety is predicted by openness and an entrepreneurial personality profile. Skill variety is also encouraged by an entrepreneurial personality profile. From a gender perspective, there is indeed a gap in entrepreneurial intentions. While a positive correlation has been found between the early variety of subjects and being female, there are negative correlations between the other two variables, education and work related Skill variety, and being female. The negative effect of work-related skill variety is the strongest. The results of this dissertation are relevant for research, politics, educational institutions and special entrepreneurship education programs. The results are also important for self-employed parents that plan the succession of the family business. Educational programs promoting entrepreneurship can be optimized on the basis of the results of this dissertation by making the transmission of a variety of skills a central goal. A focus on teenagers could also increase the success as well as a preselection based on the personality profile of the participants. Regarding the gender gap, state policies should aim to provide women with more incentives to acquire skill variety. For this purpose, education programs can be tailored specifically to women and self-employment can be presented as an attractive alternative to dependent employment.
A phenomenon of recent decades is that digital marketplaces on the Internet are establishing themselves for a wide variety of products and services. Recently, it has become possible for private individuals to invest in young and innovative companies (so-called "start-ups"). Via Internet portals, potential investors can examine various start-ups and then directly invest in their chosen start-up. In return, investors receive a share in the firm- profit, while companies can use the raised capital to finance their projects. This new way of financing is called "Equity Crowdfunding" (ECF) or "Crowdinvesting". The aim of this dissertation is to provide empirical findings about the characteristics of ECF. In particular, the question of whether ECF is able to overcome geographic barriers, the interdependence of ECF and capital structure, and the risk of failure for funded start-ups and their chances of receiving follow-up funding by venture capitalists or business angels will be analyzed. The results of the first part of this dissertation show that investors in ECF prefer local companies. In particular, investors who invest larger amounts have a stronger tendency to invest in local start-ups. The second part of the dissertation provides first indications of the interdependencies between capital structure and ECF. The analysis makes clear that the capital structure is not a determinant for undertaking an ECF campaign. The third part of the dissertation analyzes the success of companies financed by ECF in a country comparison. The results show that after a successful ECF campaign German companies have a higher chance of receiving follow-up funding by venture capitalists compared to British companies. The probability of survival, however, is slightly lower for German companies. The results provide relevant implications for theory and practice. The existing literature in the area of entrepreneurial finance will be extended by insights into investor behavior, additions to the capital structure theory and a country comparison in ECF. In addition, implications are provided for various actors in practice.
This dissertation looked at both design-based and model-based estimation for rare and clustered populations using the idea of the ACS design. The ACS design (Thompson, 2012, p. 319) starts with an initial sample that is selected by a probability sampling method. If any of the selected units meets a pre-specified condition, its neighboring units are added to the sample and observed. If any of the added units meets the pre-specified condition, its neighboring units are further added to the sample and observed. The procedure continues until there are no more units that meet the pre-specified condition. In this dissertation, the pre-specified condition is the detection of at least one animal in a selected unit. In the design-based estimation, three estimators were proposed under three specific design setting. The first design was stratified strip ACS design that is suitable for aerial or ship surveys. This was a case study in estimating population totals of African elephants. In this case, units/quadrant were observed only once during an aerial survey. The Des Raj estimator (Raj, 1956) was modified to obtain an unbiased estimate of the population total. The design was evaluated using simulated data with different levels of rarity and clusteredness. The design was also evaluated on real data of African elephants that was obtained from an aerial census conducted in parts of Kenya and Tanzania in October (dry season) 2013. In this study, the order in which the samples were observed was maintained. Re-ordering the samples by making use of the Murthy's estimator (Murthy, 1957) can produce more efficient estimates. Hence a possible extension of this study. The computation cost resulting from the n! permutations in the Murthy's estimator however, needs to be put into consideration. The second setting was when there exists an auxiliary variable that is negatively correlated with the study variable. The Murthy's estimator (Murthy, 1964) was modified. Situations when the modified estimator is preferable was given both in theory and simulations using simulated and two real data sets. The study variable for the real data sets was the distribution and counts of oryx and wildbeest. This was obtained from an aerial census that was conducted in parts of Kenya and Tanzania in October (dry season) 2013. Temperature was the auxiliary variable for two study variables. Temperature data was obtained from R package raster. The modified estimator provided more efficient estimates with lower bias compared to the original Murthy's estimator (Murthy, 1964). The modified estimator was also more efficient compared to the modified HH and the modified HT estimators of (Thompson, 2012, p. 319). In this study, one auxiliary variable is considered. A fruitful area for future research would be to incorporate multi-auxiliary information at the estimation phase of an ACS design. This could, in principle, be done by using for instance a multivariate extension of the product estimator (Singh, 1967) or by using the generalized regression estimator (Särndal et al., 1992). The third case under design-based estimation, studied the conjoint use of the stopping rule (Gattone and Di Battista, 2011) and the use of the without replacement of clusters (Dryver and Thompson, 2007). Each of these two methods was proposed to reduce the sampling cost though the use of the stopping rule results in biased estimates. Despite this bias, the new estimator resulted in higher efficiency gain in comparison to the without replacement of cluster design. It was also more efficient compared to the stratified design which is known to reduce final sample size when networks are truncated at stratum boundaries. The above evaluation was based on simulated and real data. The real data was the distribution and counts of hartebeest, elephants and oryx obtained in the same census as above. The bias attributed by the stopping rule has not been evaluated analytically. This may not be direct since the truncated network formed depends on the initial unit sampled (Gattone et al., 2016a). This and the order of the bias however, deserves further investigation as it may help in understanding the effect of the increase in the initial sample size together with the population characteristics on the efficiency of the proposed estimator. Chapter four modeled data that was obtained using the stratified strip ACS (as described in sub-section (3.1)). This was an extension of the model of Rapley and Welsh (2008) by modeling data that was obtained from a different design, the introduction of an auxiliary variable and the use of the without replacement of clusters mechanism. Ideally, model-based estimation does not depend on the design or rather how the sample was obtained. This is however, not the case if the design is informative; such as the ACS design. In this case, the procedure that was used to obtain the sample was incorporated in the model. Both model-based and design-based simulations were conducted using artificial and real data. The study and the auxiliary variable for the real data was the distribution and counts of elephants collected during an aerial census in parts of Kenya and Tanzania in October (dry season) and April (wet season) 2013 respectively. Areas of possible future research include predicting the population total of African elephants in all parks in Kenya. This can be achieved in an economical and reliable way by using the theory of SAE. Chapter five compared the different proposed strategies using the elephant data. Again the study variable was the elephant data from October (dry season) 2013 and the auxiliary variable was the elephant data from April (wet season) 2013. The results show that the choice of particular strategy to use depends on the characteristic of the population under study and the level and the direction of the correlation between the study and the auxiliary variable (if present). One general area of the ACS design that is still behind, is the implementation of the design in the field especially on animal populations. This is partly attributed by the challenges associated with the field implementation, some of which were discussed in section 2.3. Green et al. (2010) however, provides new insights in undertaking the ACS design during an aerial survey such as how the aircraft should turn while surveying neighboring units. A key point throughout the dissertation is the reduction of cost during a survey which can be seen by the reduction in the number of units in the final sample (through the use of stopping rule, use of stratification and truncating networks at stratum boundaries) and ensuring that units are observed only once (by using the without replacement of cluster sampling technique). The cost of surveying an edge unit(s) is assumed to be low in which case the efficiency of the ACS design relative to the non-adaptive design is achieved (Thompson and Collins, 2002). This is however not the case in aerial surveys as the aircraft flies at constant speed and height (Norton-Griffiths, 1978). Hence the cost of surveying an edge unit is the same as the cost of surveying a unit that meets the condition of interest. The without replacement of cluster technique plays a greater role of reducing the cost of sampling in such surveys. Other key points that motivated the sections in the dissertation include gains in efficiency (in all sections) and practicability of the designs in the specific setting. Even though the dissertation focused on animal populations, the methods can as well be implemented in any population that is rare and clustered such as in the study of forestry, plants, pollution, minerals and so on.
This dissertation details how Zeami (ca. 1363 - ca.1443) understood his adoption of the heavenly woman dance within the historical conditions of the Muromachi period. He adopted the dance based on performances by the Ōmi troupe player Inuō in order to expand his own troupe’s repertoire to include a divinely powerful, feminine character. In the first chapter, I show how Zeami, informed by his success as a sexualized child in the service of the political elite (chigo), understood the relationship between performer and audience in gendered terms. In his treatises, he describes how a player must create a complementary relationship between patron and performer (feminine/masculine or yin/yang) that escalates to an ecstasy of successful communication between the two poles, resembling sexual union. Next, I look at how Zeami perceived Inuō’s relationships with patrons, the daimyo Sasaki Dōyo in chapter two and shogun Ashikaga Yoshimitsu in chapter three. Inuō was influenced by Dōyo’s masculine penchant for powerful, awe-inspiring art, but Zeami also recognized that Inuō was able to complement Dōyo’s masculinity with feminine elegance (kakari and yūgen). In his relationship with Yoshimitsu, Inuō used the performance of subversion, both in his public persona and in the aesthetic of his performances, to maintain a rebellious reputation appropriate within the climate of conflict among the martial elite. His play “Aoi no ue” draws on the aristocratic literary tradition of the Genji monogatari, giving Yoshimitsu the role of Prince Genji and confronting him with the consequences of betrayal in the form of a demonic, because jilted, Lady Rokujō. This performance challenged Zeami’s early notion that the extreme masculinity of demons and elegant femininity as exemplified by the aristocracy must be kept separate in character creation. In the fourth chapter, I show how Zeami also combined dominance (masculinity) and submission (femininity) in the corporal capacity of a single player when he adopted the heavenly woman dance. The heavenly woman dance thus complemented not only the masculinity of his male patrons with femininity but also the political power of his patrons with another dominant power, which plays featuring the heavenly woman dance label divine rather than masculine.
Die Arbeit geht von der These aus, dass zwischen Webers Konzept einer verstehenden Soziologie und der materialen Studie "Die Protestantische Ethik und der Geist des Kapitalismus" (PE) eine Differenz in Form einer Mehrleistung auf Seiten der PE besteht. Diese Annahme fußt auf der Beobachtung, dass die PE verschiedene Perspektiven auf die Entstehung sinnhafter Handlungsorientierungen offeriert und sich gleichsam Strategien zu deren Plausibilisierung identifizieren lassen. Derartige Zusammenhänge wurden von Weber in den methodologischen Schriften scheinbar nur am Rande thematisiert und die entsprechenden Passagen erwecken den Eindruck, dass die Frage nach der Geschichtlichkeit der sinnhaften Handlungsorientierungen lediglich als Prämisse bzw. als Begründung für die Notwendigkeit einer verstehenden Sinnerfassung Beachtung findet. Diese Beobachtung bestimmt den weiteren Gang der Untersuchung und führte zu einem argumentativen Aufbau, welcher sich als Dreischritt beschreiben lässt: a) Eine Diskussion des Erklärungsprofils von Webers Konzept einer verstehenden Soziologie sowie Beispiele für vermutete Mehrleistungen auf Seiten der PE dienen zunächst der genaueren Explikation der identifizierten Problemstellung (vgl. Abschnitt I). Hierauf aufbauend erweisen sich mit Blick auf den aktuellen Forschungsstand b) jene Argumentationszusammenhänge der materialen Forschung als problematisch bzw. in ihrer logischen Beziehung zur Methodologie Webers als weiterhin ungeklärt, welche in Abschnitt I zunächst auf eine Mehrleistung auf Seiten der PE hindeuten. Hierbei zeigt eine gegenüberstellende Untersuchung von Vertretern von Einheitsthesen (vgl. Prewo 1979, Schluchter 1998, Collins 1986a) sowie Vertretern von Differenzthesen (vgl. v. Schelting 1934, Bendix 1964, Kalberg 2001), dass der aktuelle Diskussionsstand weiterhin durch offene Fragen und Unstimmigkeiten charakterisiert ist (vgl. Abschnitt II). Implizite Antworten auf diese Probleme des aktuellen Diskussionsstands lassen sich über c) einen erneuten rekonstruierenden Blick auf die in der PE enthaltenen Zusammenhänge und Plausibilisierungsstrategien gewinnen. Hier ist die Strategie doppelseitig angelegt: Für einen Teil der identifizierten Probleme ist es von besonderer Bedeutung, einen systematischen Einblick in die in der PE enthaltenen Zusammenhänge zu gewinnen (vgl. Abschnitt III). Die hierbei gewonnenen Erträge dienen als Grundlage zur adäquaten Rekonstruktion der methodischen Umsetzung und ermöglichen ein Verständnis davon, wie Weber die in den Fokus der Forschung gestellten Phänomene zu erklären suchte (vgl. Abschnitt IV).