abstract: Soft polymer composites with improved thermal conductivity are needed for the thermal management of electronics. Interfacial thermal boundary resistance, however, prevents the efficient use of many high thermal conductivity fill materials. Magnetic alignment of ferrous fill material enforces percolation of the high thermal conductivity fill, thereby shifting the governing boundary resistance to the particle- particle interfaces and increasing the directional thermal conductivity of the polymer composite. Magnetic alignment maximizes the thermal conductivity while minimizing composite stiffening at a fill fraction of half the maximum packing factor. The directional thermal conductivity of the composite is improved by more than 2-fold. Particle-particle contact engineering is then introduced to decrease the particle- particle boundary resistance and further improve the thermal conductivity of the composite. The interface between rigid fill particles is a point contact with very little interfacial area connecting them. Silver and gallium-based liquid metal (LM) coatings provide soft interfaces that, under pressure, increase the interfacial area between particles and decrease the particle-particle boundary resistance. These engineered contacts are investigated both in and out of the polymer matrix and with and without magnetic alignment of the fill. Magnetically aligned in the polymer matrix, 350nm- thick silver coatings on nickel particles produce a 1.8-fold increase in composite thermal conductivity over the aligned bare-nickel composites. The LM coatings provide similar enhancements, but require higher volumes of LM to do so. This is due to the rapid formation of gallium oxide, which introduces additional thermal boundaries and decreases the benefit of the LM coatings. The oxide shell of LM droplets (LMDs) can be ruptured using pressure. The pressure needed to rupture LMDs matches closely to thin-walled pressure vessel theory. Furthermore, the addition of tungsten particles stabilizes the mixture for use at higher pressures. Finally, thiols and hydrochloric acid weaken the oxide shell and boost the thermal performance of the beds of LMDs by 50% at pressures much lower than 1 megapascal (MPa) to make them more suitable for use in TIMs. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2019

Developments in micro and nano technology have great potential in many applications. Two applications that will be addressed in this work are self assembly of microdevices and Electrowetting in microfluidics. Capillary forces are the most critical factor in both of these techniques and need proper characterization. This thesis describes a detailed study of these forces and explains how they were utilized as an effective source of drive in high end applications. Self assembly is a promising alternative to conventional pick and place robotic assembly of micro components. Its benefits include parallel integration of parts with low equipment costs. Various approaches to self assembly have been demonstrated, yet demanding applications like assembly of micro-optical devices require increased positioning accuracy. This thesis proposes a new method for design of self assembly bonds that addresses this need. Current methods have zero force at the desired assembly position and low stiffness. The proposed method uses a substrate assembly feature to provide a high accuracy alignment guide to the part. The capillary bond region of the part and substrate are then modified to create a non-zero positioning force to maintain the part in the desired assembly position. Capillary force models show that this force aligns the part to the substrate assembly feature and reduces the sensitivity of part position to process variation. Thus, the new configuration analyzed proves substantial improvement in positioning accuracy of capillary self assembly. Guidelines are proposed for the design of an effective assembly bond using this new approach. Electrowetting is another application that has been successfully demonstrated as a means of drop manipulations in digital micro-fluidic devices. These demonstrations show that electrowetting actuation holds great promise, but there are also reports of erratic behavior and system degradation. While a method for electrowetting force measurement to track the degradation of the electrowetting response was demonstrated, this thesis analyzes some adverse effects in the electrowetting response due to variations during measurement of electrowetting forces, specially the variation of volume, the tilt in the part considered for measurements, and defective layer response.

Les matériaux chiraux peuvent avoir une forte influence sur la propagation de la lumière et ont attiré l'attention de la communauté des nanosciences. Les nanoparticules d'or, matériaux plasmoniques stables ayant une activité dans le visible (400 à 800 nm), sont des objets attrayants en tant que blocs de construction pour la formation de matériaux optiques. Précédemment, nous avons conçu et obtenu des Goldhelices en greffant des nanoparticules d’or sur des nano structures hélicoïdales de silice. Le travail présenté dans cette thèse vise à développer et à organiser les Goldhelices de manière à améliorer, modifier, réduire, voire même éliminer les propriétés chiroptiques. Les détails des nanostructures ainsi que la cinétique de formation de l'auto-assemblage organique utilisé comme support pour la formation de Goldhelices sont étudiés. Des Goldhelices sont ensuit organisées hiérarchiquement à l’aide de trois techniques : la microfluidique, le « dip coating » et le « Grazing Incidence Spraying ». Enfin, l’effet de ces organisations sur les propriétés optiques sont caractérisées par spectroscopies chirales et ellipsométrie. Nous démontrons qu'un tel système peut être utilisé pour la création de polariseur linéaire ou circulaire où une telle polarisation est uniquement dépendant par l'organisation des Goldhelices. / Chiral materials can have strong influence on the propagation of light and have attracted attention in the nano-science community. Gold nanoparticles (GNPs), stable plasmonic materials in the visible range (400-800 nm), are attractive objects as building blocks for optical materials. We have designed and obtained Goldhelices by grafting GNPs on silica nano-helical structures. The work presented in this thesis aims at developing tunable Goldhelices and organizing them in order to enhance, modify, reduce or even eliminate the chiroptical properties. The details of the nanostructures as well as the kinetics of formation of organic self-assembly which is used as templates for the formation of Goldhelices are fully studied. The hierarchical organization of the Goldhelices is investigated by the use of three techniques, the microfluidics, the dip-coating and the grazing incident spraying. Finally, the effect of the organization on their optical properties are characterized by chiral spectroscopies and Mueller matrix polarization ellipsometry. We demonstrate that such a system can be used for the creation of linear or circular polarizer where such polarization is solely tunable by the organization of the Goldhelices.

The United States has a long-standing history of appropriating Indigenous representations for the use of mascots in athletics. Despite protest by Indigenous groups against this practice, professional athletics teams continue to appropriate Indigenous representations as mascots. The National Congress of American Indians produced a public service announcement (PSA), Proud to Be (PTB), to elicit support from the general public for changing the name/mascot Redskins. The purpose of the proposed research is to experimentally examine the effects that PTB has on support among Non-Indigenous participants, as function of political alignment. We considered two competing outcomes: The Counterproductive Hypothesis predicts the more conservative participants are, the less supportive they will be of changing the Redskin name/mascot, especially after watching the PTB rather than two control PSAs (directed at ending the word retard or reducing texting and driving). We also expect that the more conservative participants are, the less supportive they will be of either “name change” campaign, especially the one that corresponds with the PSA they view. Alternately, The Effective Hypothesis predicts if the PSA induces empathy among viewers, it could elicit support independent of political perspective. That is, participants will be supportive of changing the Redskin name/mascot after watching PTB rather than either control PSA. This effect will occur through the effects of PTB on increased empathy (specific to the target group). Preliminary analyses provide support for the Effective Hypothesis: Regardless of political perspective, participants experienced increased empathy for Indigenous People after viewing PTB, which led to increased support for the message promoted by Proud to Be.

Une masse de données importante est collectée chaque jour par les gestionnaires de site internet sur les visiteurs qui accèdent à leurs services. La collecte de ces données a pour objectif de mieux comprendre les usages et d'acquérir des connaissances sur le comportement des visiteurs. A partir de ces connaissances, les gestionnaires de site peuvent décider de modifier leur site ou proposer aux visiteurs du contenu personnalisé. Cependant, le volume de données collectés ainsi que la complexité de représentation des interactions entre le visiteur et le site internet nécessitent le développement de nouveaux outils de fouille de données. Dans cette thèse, nous avons exploré l’utilisation des méthodes d’alignement de séquences pour l'extraction de connaissances sur l'utilisation de site Web (web mining). Ces méthodes sont la base du regroupement automatique d’internautes en segments, ce qui permet de découvrir des groupes de comportements similaires. De plus, nous avons également étudié comment ces groupes pouvaient servir à effectuer de la prédiction et la recommandation de pages. Ces thèmes sont particulièrement importants avec le développement très rapide du commerce en ligne qui produit un grand volume de données (big data) qu’il est impossible de traiter manuellement. / This thesis explored the application of sequence alignment in web usage mining, including user clustering and web prediction and recommendation.This topic was chosen as the online business has rapidly developed and gathered a huge volume of information and the use of sequence alignment in the field is still limited. In this context, researchers are required to build up models that rely on sequence alignment methods and to empirically assess their relevance in user behavioral mining. This thesis presents a novel methodological point of view in the area and show applicable approaches in our quest to improve previous related work. Web usage behavior analysis has been central in a large number of investigations in order to maintain the relation between users and web services. Useful information extraction has been addressed by web content providers to understand users’ need, so that their content can be correspondingly adapted. One of the promising approaches to reach this target is pattern discovery using clustering, which groups users who show similar behavioral characteristics. Our research goal is to perform users clustering, in real time, based on their session similarity.

Chromosome alignment is highly conserved in all eukaryotic cell divisions. Microtubule (MT) -based forces generated by the mitotic spindle are integral for proper chromosome alignment and equal chromosome segregation. The kinetochore is a multi-subunit protein complex that assembles on centromeric regions of chromosomes. Kinetochores tether chromosomes to MTs (K fibers) that emanate from opposite poles, in a process called biorientation. This linkage translates K fiber dynamics into chromosome movements during alignment and segregation. Stable, high-affinity kinetochore attachments promote spindle assembly checkpoint (SAC) silencing, which is active when unattached kinetochores are present. During chromosome alignment, 1) K fiber plus-end dynamics decrease, confining chromosome movements near the spindle equator, and 2) electrostatic interactions between kinetochore proteins and MTs increase. Chromosome segregation occurs as soon as all chromosomes are stably attached to microtubules and the SAC has been silenced. SAC silencing and chromosome alignment are temporally coordinated during normal divisions, implying that the mechanisms regulating K fiber dynamics and kinetochore affinity must be linked. Interestingly, HeLa cells depleted of a kinesin-8 motor Kif18A, known for its role in promoting chromosome alignment, display a SAC-dependent mitotic delay due to kinetochore-MT attachment defects. This is puzzling, as Kif18A's function in chromosome alignment is to suppress MT growth by stably associating with MT plus-ends. Whether Kif18A is required for attachment in all cells and how it promotes kinetochore microtubule linkages are not understood. The work presented in this dissertation supports a model in which Kif18A functions as a molecular link that coordinates chromosome alignment and anaphase onset. We find that Kif18A is required to stabilize kinetochore-MT attachments during mammalian germline development, as germline precursor cells in Kif18A mutant mice are unable to divide during embryogenesis due to an active SAC. However, while all cell types require functional Kif18A for chromosome alignment, mouse primary somatic cells can still divide with normal timing. This finding indicates a cell-type specific dependence on Kif18A for stabilizing kinetochore-MT attachments, and provides evidence that this function might be separate from Kif18A's known role in chromosome alignment. Consistent with this idea, we find that an evolutionarily conserved binding motif for protein phosphatase 1 (PP1) is required for Kif18A's novel role in regulating kinetochore microtubule attachments. Kif18A-PP1 interaction is required for Kif18A-mediated dephosphorylation of the kinetochore protein Hec1, which enhances attachment. However, Kif18A's interaction with PP1 is dispensable for chromosome alignment. Thus, point mutations that disrupt PP1 binding separate Kif18A's role in stabilizing kinetochore attachments from its function in promoting chromosome alignment. Additionally, through structure function studies of the motor domain, we identified a long surface loop (Loop2) that is required for Kif18A's unique MT plus-end binding activity, which is essential for its function in confining chromosome movements. Taken together, we find that Kif18A is molecularly tuned to provide temporal control of chromosome alignment and anaphase entry.

Abstract Purpose: The purpose of this paper is to quantify if using an average intensity projection (AIP) scan or a 30% phase (mid-ventilation surrogate, MidV) scan as the reference image for patient position verification affects reproducibility of lung cancer patient alignment under free-breathing cone beam computed tomography (CBCT) image guidance and to analyze the effects of common clinical issues on registration variability. Methods: AIPs were retrospectively created for 16 lung patients (14 SBRT, 2 conventional treatments) originally planned/treated using the 30% phase MidV surrogate scan as reference. The study included 3-5 CBCTs from each patient. Registrations were performed between the AIP-CBCT and between the MidV-CBCT by 5 individuals (student, medical physics resident, medical resident, medical physicist, and attending physician) using MIM 6.2 image registration platform (Beachwood, OH). The images were rigidly registered, internal tumor volume (ITV) contours were displayed, and no rotational adjustments were allowed to reflect real treatment conditions. Additionally, the registrations for AIP-CBCT and MidV-CBCT were repeated 3 times by one individual for intra-observer variability assessment. Patient setup rotations, tumor volume, tumor motion, and breathing variability were estimated for correlation with registration variability. Results: The magnitude of the average intra-observer standard deviations from the lateral (LAT), anterior-posterior (AP), and superior-inferior (SI) directions for the AIP/CBCT and MidV/CBCT registrations were 0.9 mm and 1.2 mm, respectively. The magnitude of the average inter-observer standard deviations for the AIP/CBCT and MidV/CBCT were 1.7 mm and 1.8 mm, respectively. Average discrepancies over the whole population were found to be small; however, some individual patients presented high variability. Patient-specific cases with high variability were analyzed and observations on its potential causes are discussed. Conclusion: The differences in alignment using AIP versus MidV as the reference images are, when averaged over the population studied, very small and clinically irrelevant for PTV margins > 5mm; however, individual patients may be impacted in a clinically relevant manner if smaller margins, 3 mm and below, are used instead.

In the Middle East real estate industry, 46% of projects fail in terms of strategic dimensions. Based on the dynamic capabilities approach and contingency approach, the purpose of this exploratory multiple case study was to identify the successful strategies project leaders used to improve the alignment of projects with business strategy. Data were collected from 7 Skype semistructured interviews with real estate construction project leaders from 3 real estate organizations ranked among the top 10 in the Middle East. Public organizational documents were used for methodological triangulation. A thematic coding approach was adopted following a nonlinear sequential process that involved four stages: (a) reading and preparing the collected data, (b) coding, (c) abstracting the codes into conceptual categories, and (d) identifying the themes' relationships and patterns and creating a thematic map. The 4 themes identified were the (a) flow of strategy, (b) governance of projects during the development phase, (c) governance of projects during the delivery phase, and (d) measurement of project performance and strategic success. The results confirmed the idiosyncratic nature of the selected contexts and the need to increase some dynamic capabilities' dimensions. The contribution of this study to positive social change includes improved community lifestyle and environmental quality.

Using curriculum mapping to align the expected curriculum and the actual curriculum has been demonstrated as an effective approach for ensuring educational equity for all students. To improve student achievement, a private high school in the Midwest implemented curriculum mapping to better align curriculum and eliminate gaps and repetition between and within grade levels. The purpose of this qualitative study was to determine fundamental implementation strategies for the mapping process and teachers' and administrators' perceptions of those strategies. The theoretical framework was based on change theory. Data were collected from 10 participants through individual interviews and observations. Teachers and administrators were observed during their curricular mapping meeting time in order to record the strategies used, and each participant was interviewed in order to gather individual perceptions of the strategies used. Data were transcribed and then open coded based on repeating concepts. Thematic analysis indicated that administrators and teachers perceived a need for curriculum mapping training, using standards, collaboration time, and accountability. The outcome of the study was a professional development project for teachers incorporating curriculum mapping at the local site. Implications for positive social change include providing educational leaders with curricular alignment strategies to promote educational equity and the academic success of all students

A lack of alignment between police performance evaluation policy purposes and officer performance evaluation perceptions has implications for the organizations' resource management, officer morale, and public safety. A literature review points towards a gap existing between policy purpose statements and employee perceptions. The purpose of this study was to investigate the relationship between the policy purposes of police performance evaluations and the officers' perceptions of those evaluation experiences in 4 Ontario municipal police services. DiMaggio and Powell's (1983) Institutional theory was the foundation for this study. Data for this study were collected from 4 police services in Ontario, Canada. The data consisted of police performance evaluation policies and in-person interviews with 12 officers. Data were inductively coded, and then the coded data were subjected to content analysis. Three policy purpose themes and 13 officer perception themes emerged that indicate that: 1) there seems to be a lack of alignment between the policy purpose theme of assessing work performance and eight of the perception themes; 2) officers perceived performance evaluations as negatively impacting their morale: and, 3) healthy relationships with supervisors were more useful to officers than performance evaluations in terms of performance and career outcomes and progression. Consistent with Institutional theory, officers perceived performance evaluations to be necessary even with limited utility. The positive social change implications stemming from this study include recommendations to police executives to consider alternative processes in tandem with performance evaluations to improve morale, in turn creating better opportunities for improved public and officer safety.