VictorJuiz/thesis huggingface dataset:
Advanced Modeling of the Performance of Structures Supported on Triple Friction Pendulum Bearings

Seismic isolators, and more specifically, triple friction pendulum (TFP) bearings are ideal earthquake protection technologies for use in performance-based design because they can be designed to achieve multiple performance objectives corresponding to different levels of ground shaking. TFP bearings can limit structure displacement during a design basis (or maximum considered) earthquake while the still effectively isolating the structure under the service level earthquake, reducing seismic demands on the structure and its non-structural components. Furthermore, TFP bearings allow for a gradual transfer of force to the superstructure at ultimate displacement./nThis dissertation presents an advanced bidirectional model for the TFP bearing that is based on the kinematic and compatibility relationships of the components of the bearing. To validate the model, experimental characterization tests were conducted on the shake table at the University of California, Berkeley. Two distinct types of experiments were conducted: (a) displacement-controlled tests in which the bearings were cycled through specified orbits and (b) unrestrained tests in which the table replicated ground motions recorded during earthquakes. The bidirectional displacement-controlled tests, which are the first of their kind, generated new knowledge to aid in the development and validation of TFP numerical models. The experimental results provided valuable insight into TFP bearing response and showed that the developed bidirectional model accurately captured the observed behavior of the TFP bearing. The advanced model, which includes translational and rotational degrees of freedom in both horizontal directions, tracks all component displacements as well as the change in bearing height during lateral displacements. The model is general so that no a priori conditions regarding bearing properties are required for the validity of the model. These properties make the advanced TFP model a valuable tool to explore the use TFP technology in novel applications./nTo further the use of seismic isolation in more standard applications, simplified methods are needed for design. This dissertation investigates the use of generalized modal response spectrum methods to approximate global responses of isolated buildings without the need for costly non-linear numerical simulations. The advanced nonlinear TFP model is used for evaluation of the simplified methods./nAdvanced isolation models are important and necessary for understanding the complex nonlinear dynamic behavior exhibited by seismically isolated structures, and to have confidence that performance goals are achieved under a wide variety of seismic hazards. Such models can, as shown in this dissertation, also be used to assess and improve simplified analysis methods suitable for use in routine design.

Advisor: Mahin, Stephen A
Becoming Researchers: Community College ESL Students, Information Literacy, and the Library

This qualitative case study explored the information literacy acquisition of 23 students enrolled in a learning community consisting of an advanced ESL writing class and a one unit class introducing students to research at a suburban community college library in California. As there are no other known learning communities that link an ESL course to a library course, this site afforded a unique opportunity to understand the ways in which ESL students learn to conduct library research./nStudents encountered difficulties while finding, evaluating, and using information for their ESL assignments. These problems were substantial, but more noteworthy were the strategies that the students, their ESL instructor and their instructional librarian crafted in response./nThe learning community structure enabled a number of important strategies. Strategies by the instructors included integration of the two courses' curricula; contextualized learning activities; cross-over teaching by the instructors; explicit instruction followed by guided workshop sessions. Some student strategies were persistence in asking questions, dictionary use, re-reading, and a resourceful disposition. Joint strategies included dialogue to clarify research strategies and to understand difficult text, student-crafted research techniques that were observed by instructors and shared with class; and an affirmation of the students' emerging research practices./nThis study adds to our understanding of one particular area of academic discourse acquisition in a second language--how ESL students learn to interact with information in the context of community college. This study's findings refute the idea that ESL students must wait to become researchers until their English is college-ready. ESL students in this study discovered new language forms, new texts, new ideas, and new research practices simultaneously, in large part because of the relationships that developed over time among the students, instructor and librarian.

Advisor: Hull, Glynda A
Regulation of meiotic chromosome interactions in Caenorhabditis elegans

Faithful segregation of homologous chromosomes during meiosis requires pairing, synapsis, and crossing-over. In the nematode Caenorhabditis elegans, homolog pairing and synapsis depend on pairing centers, special regions near one end of each chromosome that interact with the nuclear envelope and cytoplasmic microtubules. Pairing centers are required for nuclear reorganization at the onset of meiosis. Here, I show that pairing centers recruit the Polo-like kinase PLK-2 to induce nuclear envelope remodeling, chromosome pairing, and synapsis. Recruitment of PLK-2 is also required to mediate a cell cycle delay and selective apoptosis of nuclei containing unsynapsed chromosomes, establishing a molecular link between these two quality control mechanisms. I also show that the checkpoint kinase CHK-2 is recruited to the interface of pairing centers and nuclear envelope proteins, consistent with its role in promoting homolog interactions and nuclear reorganization. Interestingly, PLK-2 is later recruited to the axes of paired and synapsed chromosomes where it plays a downstream role in synaptonemal complex dynamics. This work reveals new functions for the conserved family of Polo-like kinases, and advances our understanding of how meiotic processes are properly coordinated to ensure transmission of genetic information from parents to progeny.

Advisor: Dernburg, Abby
Campesino Foodways in the Context of Migration and Remittances

This community-based participatory study examines how campesinos (small rural landholders) understand and act upon their understandings regarding their food pattern change in the context of a transnational family life and fiscal remittances. It examines food pattern negotiation using in-depth interviews, focus groups, filmic ethnography, participant observation and Food Pattern Analysis with rural small landholders from two communities in northern Guanajuato, México. Rural food pattern shift between pre-migration and current times are explained according to the broader economic frame of rural livelihoods, the local social context, as well as through the particularities of individual's consumption. As of the 1980's newer fluid income-based livelihoods including remittances, formal employment and cash transfers coincide with campesino's increasing access to and interaction with the commercial food system. In terms of change particularities between pre-migration and current times, it is evidenced by consumption frequency changes of key foods, the manner in which dishes are served and eaten, the freshness of the staple ingredient/s used, and the resulting food pattern diversity. Food shifts are shown to ebb and flow through time and are not linear and rigid. In regard to the question of how campesinos negotiate their food patterns in rural spaces, campesino's explanations of their consumption commonly refer to three motivating factors; these include taste preference, social returns motivation, and newer notions of time and convenience. These mechanisms taken together inform the notion that fluid income through remittances, implies not only benefits among the rural sector but costs as well. For example, while remittances enhance women's and children's agency related to their food activities and negotiation of social relations, they also support enhanced access to commercial foods, and often to highly processed foods that are high in sugar, salt and fat; they also reduce rural family production capacity as a result from displaced labor. Taken together, remittances may imply an exposed risk to nutrition-related disease and potential food insecurity. Furthermore, remittances are known to foster a sense to attain an elevated standard of living which supports an "need" to consume status foods, while also encouraging the avoidance of stigmatized regional foods. However, there is no evidence to suggest that campesinos intend to permanently sever their food production capacity; a majority of respondents still produce food.

Advisor: Organista, Kurt C.
The Aesthetics of Color Combinations

The experiments described here were aimed at characterizing people's aesthetic responses to color pairs, both in terms of which colors people prefer in combination and how the spatial organization of the component colors influences pair preference. Previous studies of preference for and harmony of color combinations have produced conflicting results. For example, some claim that harmony increases with hue similarity, whereas others claim that it decreases. In the first set of experiments, we argue that such conflicting results are resolved by distinguishing among three types of judgments about color pairs: (a) preference for the pair as a whole, (b) harmony of the pair as a whole, and (c) preference for its figural color when viewed against its colored background. Empirical support for this distinction shows that pair preference and harmony both increase as hue similarity increases, but preference relies more strongly on component color preference and lightness contrast. Although pairs with highly contrastive hues are generally judged to be neither preferable nor harmonious, figural color preference ratings increase as hue contrast with the background increases. The present results thus refine and clarify some of the best-known and most contentious claims of color theorists. In the second set of experiments, we investigated how spatial organization influences color-pair preference asymmetries: differential preference for one color pair over another when the pairs contain the same colors in opposite spatial configurations. We found robust preference asymmetries, in which participants strongly preferred pairs with yellower, lighter figures on bluer, darker grounds. We also investigated which spatial factors influence these preference asymmetries. Relative area of the two component regions is clearly important, and relative surface-based area (i.e., after amodal figure-ground completion) is more influential than relative image-based area. Surroundedness is not required, because yellowness-blueness effects were comparable for figure-ground pairs in which the figure was surrounded by the ground and for mosaic arrangements in which the regions were adjacent and separated by a gap). Lightness-darkness effects, however, were in the opposite direction for figure-ground versus mosaic organizations: people prefer figure-ground organizations in which the smaller regions are lighter, but prefer mosaic organizations in which the smaller regions are darker. We provide possible phenomenological and ecological explanations for the reported results.

Advisor: Palmer, Stephen E.
Mechanisms and Regulation of Cellulose Degradation by Fungal Enzymes

Liquid fuels derived from plant biomass have the potential to contribute to sustainability efforts. However, the conversion of plant biomass is very difficult due to its complex nature. Cellulose, the primary component of plant cell walls, is a recalcitrant polysaccharide comprised of glucose. In nature, various fungi and bacteria enzymatically depolymerize cellulose for consumption. Understanding how cellulases are produced and function will be invaluable to the realization of cellulosic biofuels. The work here describes how a prominent cellulase interacts with cellulose during depolymerization, and how the cellulolytic fungus Neurospora crassa in part signals for the production of cellulase enzymes./nThe interactions of cellulases with cellulose are not well understood due to the recalcitrance and heterogeneity of the solid substrate. Cellobiohydrolase I, the most prominent cellulase in many fungal systems, was fluorescently labeled and monitored on the surface of crystalline cellulose. Four classes of behaviors were observed for this enzyme on the surface of cellulose: productive and linear movement, nonproductive surface diffusion, stationary, and transient association. In parallel, changes to the surface of crystalline cellulose were observed with atomic force microscopy to characterize how this enzyme modifies its substrate after degradation./nThe processes that initiate cellulase induction in Neurospora crassa have yet to be identified. A screen of deletion strains grown on cellulose was performed to isolate regulators of cellulase production. A kinase (NCU07399) was identified as a regulator of the transcriptional activation of several cellulase genes. Deletion of this kinase in Neurosporareduces the upregulation of cellulases by as much as 50-fold and also induces the secretion of a metalloprotease. The results here provide a basis for exploring the pathways involved in N. crassa cellulase production.

Advisor: Cate, Jamie H.D.
Morphology and Ion Transport in Block-Copolymer Electrolytes

The central goal of this thesis is to understand the relationship between ion transport properties and morphology in block-copolymer electrolytes. The bulk of the work focuses on the systematic measurement of ion transport properties across various morphologies. However, in the course of that work it became clear that the effects of ionic currents on block-copolymer morphologies were unknown. To address this, a study was undertaken in which block-copolymer electrolyte morphologies were determined in situ while ionic currents were passed, and the result was that ionic currents can dramatically alter block-copolymer electrolyte morphologies.

Advisor: Balsara, Nitash P
Transpulmonary Lactate and Pyruvate Kinetics

Shuttling of intermediary metabolites such as lactate and pyruvate contribute to the dynamic energy needs of tissues. Tracer kinetic studies offer a powerful method to measure the metabolism of substrates like lactate and pyruvate that are simultaneously taken up from and released into the circulation by organs. We examined the transpulmonary lactate and pyruvate kinetics in an anesthetized rat model during an unstimulated (Con), lactate clamp (LC) and epinephrine infusion (Epi) using a primed-continuous infusion of [U-13C]lactate and pyruvate. Compared to Con and Epi stimulation, LC significantly increased mixed central venous ([v]) and arterial ([a]) pyruvate and lactate concentrations (P < 0.05). Transpulmonary net lactate and pyruvate balances were positive during all three conditions indicating net metabolite uptake. Net balance was significantly greater during epinephrine stimulation compared to the unstimulated control for both lactate and pyruvate (P < 0.05). Tracer measured lactate fractional extractions were similar for unstimulated and lactate clamp conditions, but negative during Epi stimulation when a transpulmonary production of lactate from venous pyruvate occurred. Tracer measured pyruvate fractional extraction averaged 42.8 ± 5.8% for all three conditions, and was significantly higher during epinephrine stimulation (P < 0.05) than during either Con or LC conditions, which did not significantly differ from each other. Lactate total release (= tracer measured uptake - net release) increased due to a lactate load (i.e., LC) and decreased (i.e., negative) from epinephrine stimulation because of the transpulmonary pyruvate to lactate conversion. Pyruvate total release was significantly higher during epinephrine stimulation (400 ± 100 µg/min) vs. Con (30 ± 20 µg/min) (P < 0.05). For lactate, we conclude that transpulmonary concentration difference measurements across the lungs provide an incomplete - and perhaps misleading - picture of parenchymal lactate metabolism, especially during epinephrine stimulation. Regarding pyruvate, significant extraction occurs during circulatory transport across the lungs. The extent of pulmonary parenchymal pyruvate extraction predicts high expression of monocarboxylate (lactate/pyruvate) transporters (MCTs) in the tissue and western blot analysis of whole lung homogenates detected three isoforms: MCT1, MCT2, and MCT4. We conclude that a critical site of circulating pyruvate extraction resides in the lungs. Furthermore, during times of elevated circulating pyruvate or epinephrine stimulation, pyruvate extraction increases.

Advisor: Brooks, George A
Design and Fabrication of Optical Metamaterials and Their Nano Manufacturing Methods

Metamaterials have opened a new field of optics in science and engineering. Negative refraction has been achieved by manipulating permittivity and permeability to be negative using the combination of SRRs (split ring resonators) and metal wires and the fishnet structure. However, the fishnet design suffers two significant disadvantages: anisotropy and scalability. The fishnet metamaterial needs a specific polarization direction because of the limitations of anisotropic design. In addition, the conventional projection photolithography approach to nanoscale manufacturing is facing possibly insurmountable challenges in economically producing the next generation of semi-conductor integrated circuits. Maskless nanolithography is a potentially agile and cost effective approach, but most of the current solutions have throughputs that are too low for viable manufacturing purposes. This dissertation presents novel isotropic and chiral metamaterials as well as a plasmonic lithography approach to mass metamaterial manufacturing./nThis dissertation reports two new designs of metamaterial which have a negative index of refraction and overcome the disadvantage of conventional metamaterials. The design of a chiral metamaterial is proposed, fabricated, and measured to prove negative index of refraction. Furthermore, a tunable chiral metamaterial is proposed, which is able to switch left and right circular polarized light dynamically by an external control beam. Also shifted bars and rings create a negative refractive metamaterial which is isotropic and randomly distributed. In this thesis, two shifted rings structure are proved to have a negative index of refraction independent of the direction of polarized light or without polarization. Beside applications of negative refraction, other applications are studied. The split ring resonator is one of the basic structures of metamaterial and this structure can be used to measure mode volume and single molecule detection by far field method./nFor the nano manufacturing method, using the plasmonic nanolithography (PNL) approach, 22-nm half-pitch direct pattern writing was successfully demonstrated using ultra-fast laser assisted nanoscale heat management and advanced plasmonic airbearing flying head designs. In addition, the details of micro and nano fabrication methods are introduced and they cover all of the structures proposed in this thesis.

Advisor: Zhang, Xiang
Catastrophes of Redemption: Modernism and Fascism in Norway

This study examines selections from the work of three modernist writers who also supported Norwegian fascism and the Nazi occupation of Norway: Knut Hamsun (1859-1952), winner of the 1920 Nobel Prize; Rolf Jacobsen (1907-1994), Norway's major modernist poet; and Åsmund Sveen (1910-1963), a fascinating but forgotten expressionist figure. In literary studies, the connection between fascism and modernism is often associated with writers such as Ezra Pound or Filippo Marinetti. I look to a new national context and some less familiar figures to think through this international issue. Employing critical models from both literary and historical scholarship in modernist and fascist studies, I examine the unique and troubling intersection of aesthetics and politics presented by each figure./nAfter establishing a conceptual framework in the first chapter, "Unsettling Modernity," I devote a separate chapter to each author. Analyzing both literary publications and lesser-known documents, I describe how Hamsun's early modernist fiction carnivalizes literary realism and bourgeois liberalism; how Sveen's mystical and queer erotic vitalism overlapped with aspects of fascist discourse; and how Jacobsen imagined fascism as way to overcome modernity's culture of nihilism. In various ways, I argue, the intellectual orientation that motivates their turn to fascist utopianism also lies behind their modernist urge to create new anti-bourgeois and anti-realist forms of artistic expression./nEach case shows a transition from an aesthetic form of anti-rationalism or anti-nihilism to political form of renewal - a shift from a literary encounter with modernity's scene of chaos and reduction to an ideological fantasy of redemption via fascism. As we know, the sort of redemption that Hamsun, Sveen, and Jacobsen imagined to be embodied in European fascism turned out catastrophically - for their own postwar lives and compromised legacies, but more importantly for the millions of people they never knew who died in the Nazi genocide.

Advisor: Sandberg, Mark
Pontrjagin forms on certain string homogeneous spaces

In this thesis, we study the topology and geometry of homogeneous spaces of the form $G/T^k$, where $G$ is a compact semisimple Lie group, $T^k$ is an embedded torus in $G$. We say that a principal $Spin(n)$-bundle $P\rightarrow M$ admits a string structure if the structure group lifts to $String(n)$. In particular, a spin manifold is string if the principal $Spin(n)$-bundle associated to the tangent bundle has a string structure. It's known that $G/T^k$ are string manifolds and we prove the uniqueness of string structures on $G/T^k$ when $G$ is simply connected . There is a canonical metric on $G/T^k$, which has positive Ricci curvature. We deform this metric to a 1-parameter family of invariant metrics on $G/T^k$. We prove that the first Pontrjagin forms associated to the Levi-Civita connection of these metrics do not vanish. This verifies a conjecture by Redden-Stolz on the TMF-Witten genus of Ricci positive string manifolds.

Advisor: Teichner, Peter