Zugl.: Berlin, Freie Univ., Diss., 2006

The ant genus Lasius (Formicinae) arose during the early Tertiary approximately 65 million years ago. Lasius is one of the most abundant and widely distributed ant genera in the Holarctic region, with 95 described species placed in six subgenera: Acanthomyops, Austrolasius, Cautolasius, Chthonolasius, Dendrolasius and Lasius. Many species of Lasius have been central to numerous species-level studies and the focus of many ecological, agricultural, and behavioral investigations. The focus of this study was to use molecular phylogenetic analysis of 781 base pairs of the mitochondrial gene cytochrome oxidase I (COI) and 251 base pairs of an anonymous nuclear gene (ANG) to address questions about the evolutionary relationships of North American Lasius species and subgenera. These relationships were used to better understand the biological and evolutionary complexities associated with these species given their North American distributions. The resulting hypotheses generated in this study from the analyses of these genes produced unexpected patterns of phylogenetic placement of Lasius species and subgenera. A number of biological processes alone or together could explain these patterns, including interspecific hybridization and gene introgression, incomplete lineage sorting, and the presence of multiple cryptic species.

At this point, along with big media tide evolution, the emerging network media already carves up of influence the original television. Some communication effects which originally occur on the television also have the possibility to appear on the network media when young people spend more time and higher frequency in network than TV. Looked from the media angle, the computer game is also an item of electronic media tool can instill the value into young people¡¦s mind, and it products the media effect does not allow to belittle when young people spend long time and actively access the computer game. "On-line game" is the media owns the characteristic of network and the computer game. Not only has excellently designed script to attract player¡¦s notice but also has the interaction of network and anonymous of hypothesized world. At that time Gamania sold South Korean on-line game "Lineage", he proposed a slogan :Realizes matter which you usually do not dare to do, therefore it attracts multitudinous people to join. Nowadays ¡§Lineage¡¨ has is known as 660 ten thousand above members, it has the media effect to be not allow to neglect. On-line game and traditional PC game biggest difference lies in its story which not beforehand arranges; therefore On-line game product life is longer than PC game relatively. Society group forms which in the game process, imperceptibly caused users to condense the high loyalty. The reappearance of "Experience" is returns to realize the activity of consciousness, including thought or image which produces regarding the primitive experience reflection, recollection and reorganization. Cultivation function is a long time course. Teenagers who is being in the phase that models with personality and moral value maybe be influenced to constitute the cognition of our world by family,¡@interactively study between the associates, even each kind of electronic media content. The idiom "Has a limited view of the day" is suitable to describe how the people cognize the world by the media. Symbolist, Perice, pointed out that symbol interaction process is decided by the relationship of sign, signifier, and signified. According to Saussure view, signifier, and signified both are produced by human communication, "the relations" namely are the connotation made by each other. It is both sides depend on the convention or the agreement formation, and it is a part of cultural. When ¡§Lineage¡¨ provides the news is main message for user to depend on constructing social reality, it will own the condition to create cultivation effect. In other words, cultivation effect is supposed not only the news receive or study. The individual psychic mechanism which people take in on-line game perhaps is a key of cultivation effect. The cultivation effect of ¡§Lineage¡¨ occurs is because players to receive the information narrowly only by the pipeline from the game world, or person, matter and thing which are about the game. After people regarding the world multiplicatively, he will not only understand the society and the environment solely from some at the same time, but has taken a mistake "to have a limited view of the day".

Zugl.: Berlin, Freie Univ., Diss., 2006

No description available.

“The scientist, by the very nature of his commitment, creates more and more questions, never fewer. Indeed the measure of our intellectual maturity, one philosopher suggests, is our capacity to feel less and less satisfied with our answers to better problems.” ~G.W. Allport, Becoming, 1955 It will be interesting to look back at this thesis in a few decades and reflect on how the questions and interpretation of data in the field of developmental biology have changed. Indeed, a biologist currently in their twilight years might reflect on their youth, before the discovery of hereditary material, and compare that bookend with the range of genome sequences and related knowledge currently available. How long will it take before this thesis reads like a debate about whether the male or female contributed the ‘homunculus,’ a miniature preformed human to the embryo that grows into an adult? In this thesis I asked three related questions: whether the role of Oct4 during embryogenesis provides insight into its contribution to pluripotency; how surfaceome changes contribute to functional maturation of neural stem cells and to what extent the murine genome is imprinted. Our data indicate that Oct4 is required for posterior expansion. We propose that the function of the protein is conserved, but that its expression has been coopted to yield different cell types based on its combination with different factors. We show that fundamental aspects of cell biology are altered during the maturation from pluripotent populations to neural stem cells, and identify mediators of proliferation, survival and adhesion that distinguish neural stem cell regulation from their precursors. Finally, we validated discovery of a dozen novel imprinted transcripts using a genomic approach. These discoveries will contribute to a holistic view of the causes and consequences of imprinting, but do not support a paradigm shift in the scale and consequences of imprinting.

“The scientist, by the very nature of his commitment, creates more and more questions, never fewer. Indeed the measure of our intellectual maturity, one philosopher suggests, is our capacity to feel less and less satisfied with our answers to better problems.” ~G.W. Allport, Becoming, 1955 It will be interesting to look back at this thesis in a few decades and reflect on how the questions and interpretation of data in the field of developmental biology have changed. Indeed, a biologist currently in their twilight years might reflect on their youth, before the discovery of hereditary material, and compare that bookend with the range of genome sequences and related knowledge currently available. How long will it take before this thesis reads like a debate about whether the male or female contributed the ‘homunculus,’ a miniature preformed human to the embryo that grows into an adult? In this thesis I asked three related questions: whether the role of Oct4 during embryogenesis provides insight into its contribution to pluripotency; how surfaceome changes contribute to functional maturation of neural stem cells and to what extent the murine genome is imprinted. Our data indicate that Oct4 is required for posterior expansion. We propose that the function of the protein is conserved, but that its expression has been coopted to yield different cell types based on its combination with different factors. We show that fundamental aspects of cell biology are altered during the maturation from pluripotent populations to neural stem cells, and identify mediators of proliferation, survival and adhesion that distinguish neural stem cell regulation from their precursors. Finally, we validated discovery of a dozen novel imprinted transcripts using a genomic approach. These discoveries will contribute to a holistic view of the causes and consequences of imprinting, but do not support a paradigm shift in the scale and consequences of imprinting.

The ERK-MAPK pathway is a dynamic signaling module, conserved across Eukarya, and capable of processing a myriad of environmental and cellular signals. It has been implicated in controlling important cell fate decisions in many cell types and species. In mES cells, growth factor activation of the ERK-MAPK pathway is involved in the earliest stages of lineage segregation, however very little is currently known about the mechanism by which this is accomplished. Taking a loss-of-function gene targeting approach I have reexamined the relative contribution of ERK2 activity to FGF-ERK signaling. Although ERK2 depletion results in an attenuation of the combined ERK1/2 activity, this is compensated for by the hyperactivation of the remaining ERK1 isozyme. Normal ERK1/2 function can be restored to ERK2 deficient cells by transgenic expression of either ERK1 or ERK2, indicating a degree of functional redundancy between both isoforms. When subjected to the appropriate cues, lineage commitment proceeded normally in ERK2 deficient cells, however increased self-renewal was observed under standard culture conditions. Several attempts were made to further probe ERK1/2 function by siRNA depletion, and dominant negative inhibition of ERK1 in Erk2 knockout cells, however both approaches failed to provide further insight. Furthermore, taking a candidate approach, the role of Srf, a canonical target of ERK1/2 signaling, was examined. Initial experiments indicated a role for SRK in neural differentiation, however due to issues of culture adaptation and instability in several cell lines it was not possible to conclude this line of research within the time frame of this thesis. IP-MS/MS analysis identified several proteins known to interact with ERK2 and indicated an involvement in nuclear pore function through TPR as well as transcriptional and translational regulation through RSK proteins. Moreover, this study identified DUSP6 and DUSP9 as the primary induced dual specificity phosphatases that regulate ERK2 activity in mES cells. To further probe the functional significance of the ERK:p90RSK interaction I examined a mES cell line genetically depleted for PDK1, a crucial regulator of p90RSK function. This cell line exhibits no detectable p90RSK activity, however in contrast to studies in other cell lines, p90RSK activity is dispensable for mitogen-induced cFos expression in mES cells. Subsequent experiments demonstrated a requirement for PDK1 activity in either the specification or maintenance of mES cell derived neurons. Further analysis indicated that p90RSK may be involved in a negative feedback loop regulating ERK1/2 activity, and if so may represent a point whereby ERK1/2 activity can be manipulated. To examine this I determined the effect pharmacological inhibition of p90RSK has on ERK1/2 activity and self-renewal using a novel p90Rsk inhibitor, BI-D1870. Although treatment with BI-D1870 correlated with enhanced ERK1/2 phosphorylation, the offtarget effects this molecule exhibits made it impossible to draw any firm conclusions from these experiments. Overall this study has demonstrated a degree of redundancy between ERK1/2 isozymes in mES cells. It has highlighted the complex nature of ERK1/2 regulation as well as the robustness of this pathway to perturbations in ERK dose. Furthermore, it has underscored some of the common pitfalls encountered when studying differentiation phenotypes in mES cells. Although this study failed to highlight anything more than a coincidental relationship between ERK1/2 activity and self-renewal capacity of mES cells, it has helped to highlight some important behavioral characteristics of the FGF-MAPK pathway in mES cells and provide a platform for further study.

This thesis is an examination of the evolution of blood ideology, which is to say the use of blood as an organizing metaphor, in Japanese society. I begin with the development of blood as a substance of significant in the eighth century and trace its development into a metaphor for lineage in the Tokugawa period. I discuss in detail blood's conceptual and rhetorical utility throughout the post-Restoration period, first examining its role in establishing a national subjectivity in reference to both the native intellectual tradition of the National Learning and the foreign hegemony of race. I then discuss the rationalization of popular and national bloodlines under the auspices of the popular eugenics movement, and the National Eugenics Bill. Then, I discuss the racialization this conception of blood inflicted on the Tokugawa era Outcastes, and its persistent consequences. Through the incongruity of the Outcastes ability to "pass" despite popular expectations that their blood pollution was visibly demonstrative, I introduce the notion of blood anxiety. Next, I address the conceptual and rhetorical role blood played in articulating Japan's empire and imperial ambitions, focusing on the Theory of Common Descent and the Investigation of Global Policy with the Yamato Race as Nucleus report. I follow this discussion with a detailed examination of the postwar reconceptualization of national subjectivity, which demands native bloodlines and orthodox cultural expressions, and which effectively de-legitimized minority populations. As illustration of this point, I describe the impact of this new subjectivity on both the Zainichi and the Nikkeijin in lengthy case studies. Finally, I conclude this examination with a consideration of blood ideology's representation in popular culture. I argue that the subgenre of vampire media allegorizes many of the assumptions and anxieties surrounding blood that have developed since the Restoration, and demonstrates the imprint of blood ideology on contemporary society. / text

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [78]-93).