Because cognitive categories associated with the evaluation of a working relationship are stable at times, yet dynamic under specific conditions, understanding leader-member exchange (LMX) and identifying cognitive correlates associated with exchange quality is perplexing (Foti, Knee & Backert, 2008). The purpose of this study was to investigate how congruence between a leader's and follower's leader and follower prototypes affects the quality of the leader-member exchange relationship as assessed by each partner in the dyadic pair. Leaders and followers in 68 dyadic pairs performed a series of tasks in a laboratory setting. Multiple assessments of liking and trust for each other, as well as LMX quality from their perspective were made. Congruence on leader prototypes significantly predicted follower assessed LMX; followers' liking and trust for leaders fully mediated this relationship. In addition, congruence on follower prototypes significantly predicted leader assessed LMX; leaders' liking for followers fully mediated this relationship. These results emphasize the reciprocal nature of LMX relationships. Practical implications of having high quality LMX include, but are not limited to, higher satisfaction and commitment, less conflict, and higher performance ratings. / Master of Science

The present study employed a novel approach to extend current knowledge of how ideal leader prototypes and self-concepts solely and dually influence leader categorization and effectiveness judgments. Cluster analysis and policy-capturing were employed to examine independent and dependent variables as patterns. Findings partially supported hypotheses and corroborated previous research. Leader categorization and effectiveness judgments were self-affirming across multiple managerial performance scenarios; implicit policies varied based on the pattern of traits exhibited within their self-concepts and ideal leader prototypes. On average, people who endorsed prototypical ideal leader prototypes and self-concepts were more stringent compared to individuals with less prototypical patterns. They categorized fewer managers as leaders, perceived them as less effective, and weighed Planning, Motivating, and Controlling performance behaviors more in their judgments. The study also showed ideal leader prototypes explained variance in implicit policies for leader categorization and effectiveness beyond the variance accounted for by self-concepts; however, the self-concept remained a significant predictor of implicit policies for leader effectiveness. This novel finding suggests the self-concept, like the ideal leader prototype, is relevant in weighting performance behaviors for effectiveness judgment. / Ph. D.

The sun is constantly emitting electrons and ions as magnetized plasma, forming the solar wind and carrying with it the sun’s rotating magnetic field. The solar wind subsequently interacts with Earth’s magnetosphere and the magnetospheres of other planets. Occasionally large amounts of magnetized plasma are released at one time in a Corona mass ejection (CME). When the CME interacts with Earth’s magnetic field, it induces perturbations that may have a significant impact on critical infrastructure, for instance, by disturbing communication systems, and inducing currents on pipelines and electric power lines, which in turn may cause increased corrosion or blackouts, among other effects. In this dissertation, we analyze measured electrical signals provided to us by the Finnish Meteorological Institute, which were induced by geomagnetic storms on pipelines located in Finland and recorded in 2003. Specifically, we perform a wavelet leader multifractal analysis of these current signals to generate singularity spectra, and then using the bootstrapping technique, we apply statistical tests to show that these signals exhibit multifractal characteristics. We also performed surrogate testing to show that these characteristics were unique to the signal. / Ph.D. / Earth’s weather affects all of us every day. The solar space environment has weather of its own that affects us as well. Storms of a size that far exceed anything on Earth can impact Earth and affect our infrastructure. One of the most powerful phenomena that occur, called solar corona mass ejections, results when the sun ejects a large amount of plasma. This can interact with the Earth’s magnetic field, which in turn induces perturbations that may have a significant impact on critical infrastructure, for instance, by disturbing communication systems, and inducing currents on pipelines and electric power lines. The currents can cause increased corrosion or blackouts, among other effects. In this dissertation, we analyze measured electrical signals provided to us by the Finnish Meteorological Institute, which were induced by geomagnetic storms on pipelines located in Finland and recorded in 2003. Specifically, we perform a statistical analysis of these current signals to decide whether they exhibit multifractal characteristics.

Novice principals leading rural schools experience unique challenges that define their leadership practices. The purpose of this qualitative study was to examine how novice principals interpret and understand the challenges they experience as developing leaders within a rural school setting in Virginia. The research question for the study was, what challenges do novice principals situated in a rural setting in Virginia experience as leaders of their schools? This study adds to the existing body of research on the challenges novice principals face as leaders of schools situated within a rural community. For this study, six novice principals working in Rural-Remote (Code 43) schools (as defined by the National Center for Education Statistics) in Virginia participated in a 45-minute, one-on-one interview. The findings revealed that the novice rural principals experienced unique challenges with hiring staff, managing limited budgets, wearing multiple hats, distributed leadership, meeting their community's expectations for accessibility and visibility, readily available collaboration opportunities with professionals in similar roles, and intense feelings of ultimate responsibility. Participants hired with previous administrative experience within the district reported smooth transitions to the principalship. Although the participants reported limited activities from their districts to assist with understanding the rural setting, they expressed satisfaction with the overall support provided by their school district. The implications could help school districts, policymakers, and principal preparation programs effectively manage rural principal successions by establishing mentorship programs; providing field experience to aspiring principals; creating robust principal induction programs; and finding creative solutions to attract, hire, and retain rural school staff. / Doctor of Education / Novice principals leading rural schools experience unique challenges that define their leadership practices. This research focused on how novice principals interpret and understand the challenges they experience as developing leaders within a rural school setting in Virginia. The research question for the study was, what challenges do novice principals situated in a rural setting in Virginia experience as leaders of their schools? For this study, six novice principals working in Rural-Remote (Code 43) schools (as defined by the National Center for Education Statistics) in Virginia participated in a 45-minute, one-on-one interview. The implications could help school districts, policymakers, and principal preparation programs effectively manage rural principal successions by establishing mentorship programs; providing field experience to aspiring principals; creating robust principal induction programs; and finding creative solutions to attract, hire, and retain rural school staff.

Leader prototypes are our expectations for attributes a leader should possess, and these prototypes guide our perceptions and judgments of others with regard to leadership. This dissertation uses a connectionist perspective of leadership to investigate differences in perceptions and judgments of male and female leaders, and provides the first empirical test of Hogue and Lord's (2007) model for gender bias in leadership. In Study 1, leader prototypes are investigated as the mediating process through which perceptions of male and female leaders differ. Furthermore, leader and perceiver gender as investigated as contextual and person factors which impact the accessibility of leader prototypes, thus consequently impacting perceptions and judgments of leaders. The use of leader prototypes in remembering a leader's past behaviors reflects the use of a semantic memory system, where the leader behaviors recalled are influenced by our expectations of the leader, rather than whether the leader actually demonstrated those behaviors. Thus, masculine leadership behaviors demonstrated by a female leader may be discounted, and the leader behaviors recalled may be influenced by gender roles. Study 2 investigates an episodic memory intervention to increase the memory accuracy of leader behaviors as a means to reduce biases in judgments of female leaders. Overall, Study 1 results suggest that activation of agentic attributes; specifically tyranny and masculinity are impacted by leader gender, such that the accessibility of those attributes was higher for male leaders. Contrary to predictions, female leaders did not result in greater accessibility of communal attributes in the leader prototype. No impact of perceiver gender was seen on this mediation process. Subsequently, accessibility of these attributes impacts participants' perceptions and judgments of leadership. Study 2 results indicate behavior recognition accuracy of communal behaviors drives participants' negative perceptions and judgments of the female leader. Limitations and directions for future research are discussed. / Ph. D. / Gender bias in leadership perceptions and judgments of leaders is pervasive, and the reasons for this gender bias have been studied from a variety of perspectives. Hogue and Lord (2007) propose that this gender bias can be explained through our leader prototypes, which are our expectations for attributes a leader should have. Various situational and person factors differentially impact the accessibility of attributes in the leader prototype, consequently impacting our perceptions and judgments of leaders. In Study 1, I investigate leader and perceiver gender as factors that impact accessibility of leader prototype attributes. In Study 2, I investigate a memory system intervention targeting the use of episodic memory instead of the default semantic memory, in an attempt to increase the recognition accuracy of a leader‟s behavior, and thus reduce biases in judgments of the leader. Results, limitations, and avenues for future research are discussed.

Yes / This paper develops a theory of the subjectivity of the leader through the philosophical lens of Hegel’s master/slave dialectic and its recent interpretation by the philosopher Judith Butler. This is used to analyse the working life history of a man who rose from poverty to a leadership position in a large company and eventually to running his own successful business. Hegel’s dialectic is foundational to much Western thought, but in this paper, I rashly update it by inserting a leader in between the master, whose approval the leader needs if s/he is to sustain self-hood, and the follower, who becomes a tool that the leader uses when trying to gain that elusive approval. The analysis follows the structure of Butler’s reading of the Dialectic and develops understanding of the norms that govern how leaders should act and the persons they should be. Hard work has become for leaders an ethical endeavour, but they grieve the sacrifice of leisure. They enjoy a frisson of erotic pleasure at their power over others but feel guilt as a result. They must prove their leadership skills by ensuring their followers are perfect employees but at the same time must prove their followers are poor workers who need their continued leadership. This leads to the conclusion that the leader is someone who is both powerful and powerless. This analysis is intended not to demonize leaders, but to show the harm that follows the emphasis on leadership as a desirable and necessary organizational function.

The purpose of this study was to identify the initial steps that a planning principal takes to open a new plus one elementary school. Too often, the focus is on the completion of the bricks and mortar of the facility instead of what takes place in the building once construction is complete (Lane, 2008). "Effective planning for the opening of a new school produces an environment in which teachers can teach and students can learn effectively and efficiently" (Lane, 2008, p. 2). Thus, the opening of a new plus one school requires a well-planned, detailed, organized approach for occupying the facility as the success or failure of the school opening process weighs heavily on the ability of the planning principal (Lane, 2008). New plus one schools are continuing to be built regularly within the United States to address student enrollment increases in existing schools with limited capacity, yet there is no set of instructions to guide a planning principal. With new school construction still needed to address increasing student enrollment in local school districts, the perceptions of the initial steps planning principals take to open a new plus one elementary school are valuable. This study involved interviewing four planning principals in the Mid-Atlantic region of the United States. Interview questions sought the actions that planning principals take to start a new plus one elementary school. All four planning principals indicated that they had no playbook or guide, were self-directed and initiated support when needed, and exercised a high level of autonomy with decision making, specifically with staffing, developing a school vision, and determining the school mascot and school colors. Implications for practitioners were identified including the need for a guide or handbook, a structure of support, and training or professional development. The outcome of the study provided opportunities for future planning principals to identify the key responsibilities, experiences, and guidance recommended for opening new plus one elementary schools. / Doctor of Education / New plus one schools are continuing to be built regularly within the United States to address student enrollment increases in existing schools with limited capacity, yet there is no set of instructions to guide a planning principal. With new school construction still needed to address increasing student enrollment in local school districts, the perceptions of the initial steps planning principals take to open a new plus one elementary school are valuable. This qualitative study interviewed four planning principals from the Mid-Atlantic region of the United States that served as a planning principal within the past five years of a public K-5 elementary school, had at least three years of experience as a school administrator, and opened a new plus one school versus a rebuild. The interview questions sought the actions planning principals take to start new plus one elementary schools. All four planning principals indicated that they had no playbook or guide, were self-directed and initiated support when needed, and exercised a high level of autonomy with decision making, specifically with staffing, developing a school vision, and determining the school mascot and school colors. Implications for practitioners were identified including the need for a guide or handbook, a structure of support, and training or professional development. The outcome of the study provided opportunities for future planning principals to identify the key responsibilities, experiences, and guidance recommended for opening new plus one elementary schools. A suggestion for future research would be to expand the sample to secondary planning principals to compare and contrast responsibilities with elementary planning principals.

This thesis presents Caesar, a novel multi-leader Generalized Consensus protocol for geographically replicated systems. Caesar is able to achieve near-perfect availability, provide high performance - low latency and high throughput compared to the existing state-of-the- art, and tolerate replica failures. Recently, a number of state-of-the-art consensus protocols that implement the Generalized Consensus definition have been proposed. However, the major limitation of these existing approaches is the significant performance degradation when application workload produces conflicting requests. Caesar's main goal is to overcome this limitation by changing the way a fast decision is taken: its ordering protocol does not reject a fast decision for a client request if a quorum of nodes reply with different dependency sets for that request. It only switches to a slow decision if there is no chance to agree on the proposed order for that request. Caesar is able to achieve this using a combination of wait condition and logical time stamping. The effectiveness of Caesar is demonstrated through an evaluation study performed on Amazon's EC2 infrastructure using 5 geo-replicated sites. Caesar outperforms other multi-leader (e.g., EPaxos) competitors by as much as 1.7x in presence of 30% conflicting requests, and single-leader (e.g., Multi-Paxos) by as much as 3.5x. The protocol is also resistant to heavy client loads unlike existing protocols. / Master of Science / Today, there exists a plethora of online services (e.g. Facebook, Google) that serve millions of users daily. Usually, each of these services have multiple subcomponents that work cohesively to deliver a rich user experience. One vital component that is prevalent in these services is the one that maintains the shared state. One example of a shared state component is a database, which enables operations on structured data. Such shared states are replicated across multiple server nodes, and even across multiple data centers to guarantee availability, i.e., if a node fails, other nodes can still serve requests on the shared state; low-latency, i.e., placing the copy of the shared state in a datacenter closer to the users will reduce the time required to serve the users; and scalability, i.e., the bottleneck that a single server node cannot serve millions of concurrent requests can be alleviated by having multiple nodes serve users at the same time. These replicated shared states need to be kept consistent i.e. every copy of the shared state must be the same in all the replicated nodes, and maintaining this consistency requires that each of these replicating nodes communicate with each other and reach an agreement on the order in which the operations on the shared data should be applied. In that regard, this thesis proposes Caesar, a consensus protocol with the aforementioned guarantees that will ease the deployment of services that contain a shared state. It addresses the problem of performance degradation in existing approaches when the same part of the shared state are accessed by multiple users that are connected to different server nodes. The effectiveness of Caesar is demonstrated through an evaluation study performed by deploying the protocol on five of Amazon’s data centers around the world. Caesar outperforms the existing state-of-the-art by as much as 3.5x. Caesar is also resistant to heavy client loads unlike existing protocols.

Cells interact with their immediate fibrous extracellular matrix (ECM); alignment of which has been shown influence metastasis. Specifically, intra-vital imaging studies on cell invasion from tumor-matrix interface and wounds along aligned fibers describe invasion to occur as singular leader (tip) cells, or as collective mass of a few chain or multiple tip cells. Recapitulation of these behaviors in vitro promises to provide new insights in how, when and where cells get the stimulus to break cell-cell junctions and ensue invasion by migrating along aligned tracks. Using Spinneret based Tunable Engineered Parameters (STEP) technique, we fabricated precise layout of suspended fibers of varying diameters (300, 500 and 1000 nm) mimicking ECM dimensions, which were interfaced with cell monolayers to study invasion. We demonstrated that nanofiber diameter and their spacing were key determinants in cells to invade either as singularly, chains of few cells or multiple-chains collectively. Through time-lapse microscopy, we reported that singular cells exhibited a peculiar invasive behavior of recoiling analogous to release of a stretched rubber band; detachment speed of which was influenced with fiber diameter (250, 425 and 400 µm/hr on small, medium and large diameter fibers respectively). We found that cells initiated invasion by putting protrusion on fibers; dynamics of which we captured using a contrasting network of mismatched diameters deposited orthogonally. We found that vimentin, a key intermediate filament upregulated in cancer invasion localized within a protrusion only when the protrusion had widened at the base, signifying maturation. To develop a comprehensive picture of invasion, we also developed strategies to quantify migratory speeds and the forces exerted by cells on fibers. Finally, we extended our findings of cell invasion to report a new wound healing assay to examine gap closure. We found that gaps spanned by crosshatch network of fibers closed faster than those on parallel fibers and importantly, we reported that gaps of 375 µm or larger did not close over a 45-day period. In summary, the methods and novel findings detailed from this study can be extended to ask multiple sophisticated hypotheses in physiologically relevant phenomenon like wound healing, morphogenesis, and cancer metastasis. / Ph. D. / Disease phenomenon like cancer invasion and wound healing have a myriad of things in common including cell migration and the ability of cells to remodel their immediate environment. Often times these singular or group migratory events of cells are initiated and directed by peculiar cells called tip/leader cells that explore cellular environment and make room for migration. While research in the last few decades has yielded a tremendous wealth of information as to how biochemical factors influence their behavior, our understanding of how the biophysical properties of the environment affect their behavior is in its infancy. This lack of understanding can somewhat be attributed to the difficulty in fabricating mechanically welldefined substrate systems that can be tailored to recapture these invasive episodes in a controlled setting outside of a living organism. In this study, we utilize a novel Spinneret based Tunable Engineered Parameters (STEP) technique to fabricate mechanically tunable nanofibers that show close resemble to native cellular environment. Cells were made to interact with these fibers and it was shown for the first time that factors like fiber spacing, diameter and topography can significantly affect the types of leader cells and their trajectory. Furthermore, once these cells come out of the simulated tumors/wounds, their migratory behaviors were still affected by mechanical properties of the fibers. Similarly, we also showed for the first time that the ability of the gaps to close in simulated wound healing settings could be significantly dependent on size, shape, and properties of fibers. These findings offer a novel outlook to our current understanding of single and collective cell behavior and how the biophysical properties of the native cellular environment can affect these behaviors. This can not only expand our understanding of how this invasive episodes occur, but also help us come up with preventive measures to inhibit such episodes for a better prognosis of diseases like cancer and chronic wounds.

Det uppfattas idag som en självklarhet att fortsätta lära och utvecklas genom hela livet. Årligen spenderas stora summor på ledarutveckling, vilket har väckt ett intresse att undersöka denna form av utbildningsaktiviteter. Denna studie syftar till att undersöka vad som kan ligga till grund för valet att delta i ledarutvecklingsaktiviteter utifrån en fallstudie hos Stelena, samt hur deltagarna uppfattar att dessa aktiviteter bidrar till lärande och praktisk användbarhet. Fyra frågeställningar formulerades; Vilka motiv framkommer för deltagande i dessa aktiviteter? På vilket sätt uppfattar deltagarna att kompetenser och verktyg genereras i aktiviteterna? På vilket sätt uppfattar deltagarna att ledarutvecklingsaktiviteterna influerat deltagarna och bidragit till ett lärande? Hur uppfattar deltagarna möjligheterna att kunna använda genererade kompetenser och verktyg i sitt dagliga arbete? För att få en ingång till våra frågeställningar tog vi inledningsvis del av tidigare forskning inom området ledarutveckling. För att insamla vårt empiriska material genomfördes sju intervjuer. Därefter analyserades materialet med inspiration av pragmatisk diskursanalys, samt med hjälp av utvalda teoretiska utgångspunkter; aktivitetsteorin, proximala utvecklingszonen, samt reflekterande handling. I detta analysförfarande urskildes en norm, att individers problemformuleringar i aktiviteterna kunde ses som ett dialektiskt spel mellan det individuella och kollektiva. Resultatet visar att motiv till att delta ofta grundade sig i ett behov av stöd.  Således har det visat sig att kommunikation och reflektion i ledarutvecklingsaktiviteterna tycks generera redskapen. Likväl som kommunikation ligger till grund för verktygsskapandet uppfattades kommunikativ kompetens och ett reflekterande förhållningssätt viktigt i rollen som ledare. Ledarutvecklingsaktiviteterna har vidare bidragit med redskap vilka lärt individer hantera situationer utifrån nya perspektiv. Det har framkommit hur aktiviteterna gett en ökad förståelse för betydelsen av att lära känna sig själv, medarbetares olikheter och således hur dessa lärdomar bidrar till ett mer effektivt ledarskap. Resultatet visar hur individer upplever att de haft nytta av flera av de verktyg som genererats, både för egen del och för organisationen i stort. / Present conception is that individuals are under constant development and learning during their entire life. Every year a large amount of money is spent on leadership development. There has been an increasing interest to such educational activities. The aim of this study is to examine, what the basis beyond participation can be in leader development activities, through a case-study at Stelena, and how participants perceive that the activities contributes to learning and practical use. Four questions were framed; which motives for participation in these activities appear? In which way do participants perceive that competencies and tools generates in the activities? In which way do participants perceive that the leader development activities have influenced them and contributed to learning? How do participants perceive the ability to use acquired competencies and tools in their daily work?   In order to find answers to our questions, we took part of recent science connected to leader development. Seven interviews were done in order to collect our empirical material. With inspiration from pragmatic discourse analysis and with theoretical base, the material was analysed. Our theoretical bases are activity theory, the zone of proximal development and reflective action. In the analysis work we did distinguish a norm, that problem formulations in the activities could be seen as a dialectical game between the individual and the collective.  The result shows that motives beyond participation many times were based on a need of support. It has been shown how communication and reflection in Stelena leader development activities appear to generate tools. As well as communication and reflection is underlying the creation of tools, communicative competence and a reflective approach are seen as very useful in the role of a leader. Stelena has also provided tools, which have taught individuals to manage situations from new perspectives. The study shows how the activities increased the understanding of the importance to get to know oneself, differences of co-workers and in what way such learning contributes to more effective leadership. The result shows how individuals experienced great usefulness of those tools, both for themselves and for the organisations.