There is a long history in Kiruna of conducting research on the physics of the aurora borealis. There is also a long history of providing tourists with great opportunities to see the auroras. Planning such tourist activities can be challenging since the auroras are hard to predict. Reliable forecasts would be a valuable tool for researchers as well as for tourists and tour guides. One tool that is already available for both researchers and tourists is the all-sky camera in Kiruna, which is operated by the Swedish Institute of Space Physics (IRF). There has been a digital all-sky camera in operation in Kiruna for over 20 years. From the images captured by this camera, the IRF has developed a numerical index - the auroral index.  Forecasting time series with neural network algorithms is a well studies subject. There are many examples from a wide range of felds, including space weather. A type of neural network that has often been successfully used for time series forecasting is the Recurrent Neural Network (RNN), and more specifcally the Long short-term memory (LSTM).  This thesis evaluates the auroral index - in combination with data from the solar wind - as training data for recurrent neural networks. Furthermore, it attempts to fnd a LSTM neural network model capable of making reliable forecasts of the auroral index. The Keras and TensorFlow software libraries are used to build and train the neural network model. Some challenges with the auroral index - when utilized as training data for neural networks - are identifed. The produced LSTM neural network models are not accurate enough for deployment as a production level service. Further development might improve on this. Finally, this thesis suggests future work that may contribute to better forecasting models for auroras in the Kiruna region.

The chromosome passenger complex (CPC) is an essential mitotic regulator with key roles in mitotic processes such as chromosome condensation, spindle dynamics, chromosome bi-orientation, the spindle checkpoint and cytokinesis. The Aurora B kinase is the CPC’s catalytic subunit. Its targeting and activation are dependent on interactions with the other components of the complex: inner centromere protein (INCENP), survivin and borealin/Dasra B. INCENP serves both as a scaffolding subunit for the CPC as a whole and as an activator of Aurora B via its highly conserved INbox domain. Aurora B is a putative anti‐cancer target; several inhibitors of the kinase are currently in clinical trials. All these are ATP-analogues targeting the kinase active site. The protein-­protein interaction between Aurora B and the INCENP INbox is also essential for CPC function. Earlier studies have demonstrated that INCENP INbox mutants unable to bind and/or activate Aurora B cannot rescue lethality in the absence of endogenous INCENP. The first goal of this study was to test the in vivo effects of disrupting the interaction between endogenous wild type INCENP and Aurora B. For this, a cell-based CPC function assay was developed in HeLa cells. Using this assay, I show that expression of soluble INbox in HeLa cells produces a significant increase in multinucleated and micronucleated cells: both effects consistent with Aurora B loss of function. Expression of soluble INbox bearing the mutations W845G and/or F881A does not elicit this effect suggesting that those mutants cannot bind to Aurora B and occlude INCENP binding. The result concerning the F881A mutant contrasts with earlier reports that equivalent mutants could bind, but not activate, Aurora B. Expression of an INbox mutant lacking the C-­terminal TSS motif reported to be involved in Aurora B activation but not binding has effects similar to those of the wild type INbox. Using the INbox/Aurora B interaction as a model, a secondary goal of this study was to develop and evaluate a novel approach to identify small peptides capable of dissociating intracellular protein‐protein interactions. For this, a library of small (5-­9 residues long) circular peptides (CPs) mimicking the INbox was generated using the split intein circular ligation of proteins and peptides (SICLOPPS) methodology and assayed using the cell-­based CPC function assay. Over two successive rounds of screening, a small number of CPs were identified that caused a significant increase in rates of multinucleated and micronucleated cells. Although statistically significant, these increases were very modest. Furthermore, due to high heterogeneity in SICLOPPS processing efficiencies, it was not practicable to compare the effects of different peptides side-­by-side by transfection. The level of variation in processing efficiency – thus, CP production – was unexpectedly high and puts into question the functional complexity of more commonly used combinatorial cyclic peptide libraries derived using current SICLOPPS methodology. The results of this study are divided into three sections. The first is a methods section concerning the testing of SICLOPPS in HeLa cells and the development of a cell­‐based CPC function assay. In the second, the effects of expressing soluble INbox and mutants thereof in HeLa cells are presented. The final results section presents the results of the feasibility study of the rationally-­designed genetically encoded library approach.

Recent studies have found that EPS8, a mediator of growth factor signaling to the cytoskeleton, may upregulate expression of the FoxM1B transcription factor and aurora A kinase, both of which have been linked to oncogenic activity. Cell lines transfected with EPS8 and FoxM1B, and appropriate controls, were generated and analyzed by MTT proliferation assays and flow cytometry for relative rates of cell proliferation as well as to determine the percentage of cells in different phases of the cell cycle. qRT-PCR and western blots confirmed higher levels of EPS8, FoxM1B and Aurora A kinase in the overexpressing cell lines. To investigate the role of PI3K-dependent signaling in EPS8-mediated upregulation of FoxM1B and its targets, studies were carried out usingLY294002, an inhibitor of PI3K. In cells overexpressing EPS8, treatment with LY294002resulted in decreased expression of FoxM1B and Aurora A kinase, indicating that PI3Ksignaling mediates EPS8-dependent upregulation of FoxM1B and Aurora A kinase. The study suggests that EPS8 deregulates cell growth by affecting the expression of common regulators of cell cycle progression, in part through PI3K, a known pro-oncogenic kinase.

This essay is a musicological, analytical, and performance practice investigation of Variazioni e Toccata sopra “Aurora lucis rutilat,” op. 52 by Alberto Ginastera. Commissioned by and written for the Twin Cities Chapter of the American Guild of Organists, this piece was premiered during the National Convention of the AGO on June 18th, 1980 in Minneapolis, Minnesota, by the renowned American organist and pedagogue Marilyn Mason. Mason championed the composition for years on the concert platform, but the composition suffered neglect both by performers and scholars alike. Today, there exists not a single comprehensive study on this work, and only two recordings available. This essay seeks to clarify the composition by addressing 1) the relation between manuscript sources, the correspondence between composer and performer during and after the compositional process, recordings, and 2) by analyzing the form of the piece, by investigating its melodic relationship to the Gregorian tune, as well as by providing an examination of the text and its connection to medieval sources. I will devote a chapter to Ginastera’s biographical background, a review of the current scholarship, as well as a chapter devoted to the analysis of each single variation, thematic placement, and an overview of the harmonic relationship of endings.

In this thesis, several aspects of the convection, magnetic, and optical auroral dynamics of the high-latitude ionosphere are investigated from multi-instrument observations. The spatial and temporal relationships between nightside radar flow enhancements (NRFEs) and auroral intensifications are studied in Chapter 3. The NRFEs on open field lines usually are associated with very little accompanying auroral and magnetic activity. The NRFEs on closed field lines are often accompanied by optical auroral activity, but there is not a definite one-to-one correspondence. Both the statistical investigation and event study showed that the NRFEs may occur nearly simultaneously with the auroral intensifications. Because existing models associating the tail reconnection process and near-geosynchronous onset of substorms do not explain these correlated radar and optical observations very well, we propose a new model to explain the nearly simultaneous onset of the NRFEs and the auroral intensifications. In Chapter 4 we describe a small postmidnight substorm event on October 9, 2000 during dominantly IMF By+ Bz+ conditions. A sequence of three optical auroral intensifications and Pi2 bursts were found. The first two activations were characteristic of pseudobreakups, while the last and strongest intensification corresponded to a substorm expansive phase (EP). The auroral, magnetic and radar signatures of the event are interpreted as the consequence of three successive drift-Alfven-ballooning (DAB) mode instabilities in the near-geosynchronous orbit plasma sheet (NGOPS). About 10 minutes after the EP onset, there was a second auroral brightening. The convection feature during this second auroral brightening was consistent with the scenario of a Stage-2 EP. We suggest that the first two pseudobreakups, the Stage-1 EP, and the Stage-2 EP are related, respectively, to loading-unloading, directly driven, and internal magnetotail processes. Finally, in Chapter 5, we make some comparisons between the ionospheric plasma convection vortex structure observed by SuperDARN and the associated equivalent current pattern derived from the magnetometer observations. The discrepancies between the equivalent convection (EQC) and the SuperDARN-observed convection (SDC) pattern are explained in terms of the effect of day-night photoionization conductance gradient, and the coupling between field-aligned currents (FACs) and ionospheric conductances. In particular, we found the agreement between the EQC and SDC patterns is rather poor for a counterclockwise convection vortex. We suggest the discrepancies are probably due to a downward FAC-conductance coupling process.

Plant imagery abounds in Elizabeth Barrett Browning's novel-poem, Aurora Leigh, and critical readings have not thoroughly explored the meaning of and intent behind that imagery. Plant metaphor and images in Aurora Leigh are used to challenge the concept of Victorian women's inherently inferior "nature" and to present an argument for female equality. When traced throughout the work, plant imagery foreshadows Aurora and Marian's ultimate personal independence and familial harmony and helps the reader to understand the poem's controversial ending. Ties to three of Browning's literary influences in the selection of plant images are explored: Emanuel Swedenborg, Mary Wollstonecraft, and Samuel Taylor Coleridge. Each of these three understood and used nature imagery to significant effect in their own writings, and Browning adopted and developed those images in her work.

Plant imagery abounds in Elizabeth Barrett Browning's novel-poem, Aurora Leigh, and critical readings have not thoroughly explored the meaning of and intent behind that imagery. Plant metaphor and images in Aurora Leigh are used to challenge the concept of Victorian women's inherently inferior "nature" and to present an argument for female equality. When traced throughout the work, plant imagery foreshadows Aurora and Marian's ultimate personal independence and familial harmony and helps the reader to understand the poem's controversial ending. Ties to three of Browning's literary influences in the selection of plant images are explored: Emanuel Swedenborg, Mary Wollstonecraft, and Samuel Taylor Coleridge. Each of these three understood and used nature imagery to significant effect in their own writings, and Browning adopted and developed those images in her work.

In this thesis, several aspects of the convection, magnetic, and optical auroral dynamics of the high-latitude ionosphere are investigated from multi-instrument observations. The spatial and temporal relationships between nightside radar flow enhancements (NRFEs) and auroral intensifications are studied in Chapter 3. The NRFEs on open field lines usually are associated with very little accompanying auroral and magnetic activity. The NRFEs on closed field lines are often accompanied by optical auroral activity, but there is not a definite one-to-one correspondence. Both the statistical investigation and event study showed that the NRFEs may occur nearly simultaneously with the auroral intensifications. Because existing models associating the tail reconnection process and near-geosynchronous onset of substorms do not explain these correlated radar and optical observations very well, we propose a new model to explain the nearly simultaneous onset of the NRFEs and the auroral intensifications. In Chapter 4 we describe a small postmidnight substorm event on October 9, 2000 during dominantly IMF By+ Bz+ conditions. A sequence of three optical auroral intensifications and Pi2 bursts were found. The first two activations were characteristic of pseudobreakups, while the last and strongest intensification corresponded to a substorm expansive phase (EP). The auroral, magnetic and radar signatures of the event are interpreted as the consequence of three successive drift-Alfven-ballooning (DAB) mode instabilities in the near-geosynchronous orbit plasma sheet (NGOPS). About 10 minutes after the EP onset, there was a second auroral brightening. The convection feature during this second auroral brightening was consistent with the scenario of a Stage-2 EP. We suggest that the first two pseudobreakups, the Stage-1 EP, and the Stage-2 EP are related, respectively, to loading-unloading, directly driven, and internal magnetotail processes. Finally, in Chapter 5, we make some comparisons between the ionospheric plasma convection vortex structure observed by SuperDARN and the associated equivalent current pattern derived from the magnetometer observations. The discrepancies between the equivalent convection (EQC) and the SuperDARN-observed convection (SDC) pattern are explained in terms of the effect of day-night photoionization conductance gradient, and the coupling between field-aligned currents (FACs) and ionospheric conductances. In particular, we found the agreement between the EQC and SDC patterns is rather poor for a counterclockwise convection vortex. We suggest the discrepancies are probably due to a downward FAC-conductance coupling process.

Brain tumors are abnormal tissue masses found, either malignant or benign in nature. Medulloblastoma is a brain tumor subtype found to arise in the hind region of the brain, which is highly malignant and has poor long term prospects in general. On the basis of the driving force behind the tumor, medulloblastoma is further subgrouped into 4 categories: WNT; SHH; Group 3 and Group 4 tumors. Group 3 tumors show a high expression of N-Myc protein which is seen in certain types of cancerous cells. The cell cycle is regulated at several checkpoints by cyclin/cdk inhibitors. The primary cilium is an organelle found on the cellular surface, which has functions in cell growth, differentiation and neurogenesis. Aurora kinase is a protein kinase involved in the regulation and maintainence of the cilium. Often the cilium gets deleted from the cellular surface in tumors coupled with an increase in the kinase level inside the cells. Hence aurora kinase is found to be a viable target for therapy. Aurora kinase is also involved in stabilizing the MYCN gene by protecting it from degradation. In this project, the primary cilum was studied in neural stem cells and followed by study of its presence on tumor cells in culture. The gene involved in cilium development i.e. Kif3a was mutated and its aggressive nature was compared with that of the tumor cells. Aurora kinase was commonly found to be over-expressed in both the tumors and the mutants whereas N-Myc over-expression was seen only in tumors. Experiments suggest that cilia repression in Kif3a mutants takes place via an aurora kinase dependent pathway.

Thesis (M.S.M.)--Regis University, Denver, Colo., 2006. / Title from PDF title page (viewed on May 18, 2006). Includes bibliographical references.