Synthetic Ecologies: Design and the Ecological Imagination

Daou Ornelas, Daniel Harvard University ProQuest Dissertations & Theses 2021 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

The present historical condition has been characterized by the impasse between two seemingly opposing narratives, one of modernization, mastery, and progress (usually associated to economic growth), and another of interdependence, precaution, and balance (usually associated to ecological integrity).In addressing the relationship between design and ecology, this dissertation’s aims are threefold.First, it problematizes the relationship between design and ecology defined by the apparently self-evident discourse of mainstream environmentalism developed since the seventies around the institutional notion of sustainability. The dissertation reveals how ecology, in its different acceptations (as a scientific field, a synonym for environmentalism, and a particular worldview) played a central role in the processes of de-politicization and re-politicization of design discourse, first as a cultural metaphor in the theoretical writings of the late 1990s and early 2000s, then as the result from the maturation of political ecology accelerated by the Global Financial Crash of 2007-9.Second, drawing from a comparative literature analysis of representative texts from different bodies of ecological scholarship (environmentalism, techno-managerialism, political ecology, and ecological philosophy), the dissertation probes the limits of different instances of the ecological metaphor and the effect these have on the construction of political narratives.Third, the dissertation rearticulates the relationship between design and ecology (now understood as an aesthetic as much as a political problem) asserting that the current cultural impasse can be overcome if politico-ecologic problems are restated as design problems.

Pathways to Thriving: First- and Continuing Generation College Student Experiences at Two Elite Universities

Gable, Rachel Lyn Harvard University ProQuest Dissertations & Theses 2016 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

In this longitudinal interview-based study, I explore the self-assessed preparation, academic experiences, and social experiences of one ninety-one first-generation and thirty-five continuing generation (those with at least one parent a college graduate) students attending Harvard College and Georgetown University between the years of 2012-2016. Through random sampling techniques and iterative interviews, I examine the variation and change over time among first-generation students' descriptions of their college going experiences and compare these to their continuing generation peers. I identify points of overlap as well as factors that specifically affect first-generation students' transition into and experiences of college. I argue that a classification of first-generation students attending elite universities as either "privileged" or "disadvantaged" glosses over the nuanced and varied self-assessments of first-generation students themselves. Instead, I propose considering first-generation students' characteristics and college experiences---especially at highly selective universities---as multiplex, accommodating both privilege and disadvantage, and transitional in both nature and outcome. In short, the first-generation classification is essentially a social category defined by its liminality, not by a durable set of characteristics. Even though the first-generation experience is complex and varied, there are nonetheless policy and programmatic lessons that administrators can draw to support first-generation and all students as they transition into and proceed through college. This dissertation examines the various pathways to thriving as articulated by first-generation students themselves. In terms of academics, these include academic continuation and academic divergence in a field of study, and academic turnaround versus ongoing academic achievement among first- and continuing-generation students from diverse preparation backgrounds. In terms of social experiences, I explore the tactics of bulwarking, pride work, and assimilation as ways in which first-generation students adopt or eschew the classification as an identity feature in a given social context. Finally, I offer specific policy recommendations to administrators aiming not to see their first-generation students make it through, but to thrive in college and beyond.

Essays in Economics and Education

Turley, Patrick Ansel Harvard University ProQuest Dissertations & Theses 2016 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Education is a fundamental input of human capital formation. In this dissertation we explore topics related to how much and what time of human capital individuals invest in, and the long term-consequences of these investments. We begin with by measuring the degree to which financial incentives can affect a college student's field of study. Next, we attempt to identify genetic variants associated with increased educational attainment and examine the biological systems implicated by this analysis. Last, we test for heterogeneous treatment effects of education on health across the distribution of observed health and across a genetic predictor of health. In chapter 1, we examine whether students respond to immediate financial incentives when choosing their college major. From 2006--07 to 2010--11, low-income students in technical or foreign language majors could receive up to $8,000 in SMART Grants. Since income-eligibility was determined using a strict threshold, we determine the causal impact of this grant on student major with a regression discontinuity design. Using administrative data from public universities in Texas, we determine that income-eligible students were 3.2 percentage points more likely than their ineligible peers to major in targeted fields. We measure a larger impact of 10.2 percentage points at Brigham Young University. In chapter 2 we find that, educational attainment (EA) is strongly influenced by social and other environmental factors, but genetic factors are also estimated to account for at least 20% of the variation across individuals. We report the results of a genome-wide association study (GWAS) for EA that extends our earlier discovery sample of 101,069 individuals to 293,723 individuals, and a replication in an independent sample of 111,349 individuals from the UK Biobank. We now identify 74 genome-wide significant loci associated with number of years of schooling completed. Single-nucleotide polymorphisms (SNPs) associated with educational attainment are disproportionately found in genomic regions regulating gene expression in the fetal brain. Candidate genes are preferentially expressed in neural tissue, especially during the prenatal period, and enriched for biological pathways involved in neural development. Our findings demonstrate that, even for a behavioral phenotype that is mostly environmentally determined, a well-powered GWAS identifies replicable associated genetic variants that suggest biologically relevant pathways. Because EA is measured in large numbers of individuals, it will continue to be useful as a proxy phenotype in efforts to characterize the genetic influences of related phenotypes, including cognition and neuropsychiatric disease. In 1972, the mandatory minimum age at which a student could drop out of school in England and Wales was raised from 15 to 16, constraining roughly 15 percent of the student population. In chapter 3, we exploit this discontinuous increase in educational attainment to estimate the impact of education on body mass index (BMI) and diabetes approximately 40 years later. While previous literature found no significant effect of education on health, they were not able to investigate whether these effects vary along the distribution of health outcomes. We are able to detect large effects on BMI in the upper quantiles of observed BMI, as large as 2 BMI points at the 90th percentile of BMI, from a baseline of 35.6. Using a genetic predictor of BMI, we also find that those with higher genetic risk of obesity see smaller reductions in BMI as a result of the increase in compulsory schooling while large reductions are seen in those with low genetic risk. Taken together our results point to the importance of considering heterogeneity when estimating the impacts of education on health.

Regularized Regression in High Dimensions: Asymptotics, Optimality and Universality

Hu, Hong Harvard University ProQuest Dissertations & Theses 2021 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Regularized regression is a classical method for statistical estimation and learning. It has now been successfully used in many applications including communications, biology, astronomy, where the sizes and amounts of available data have increased substantially over the recent years. However, the theoretical understanding of this method in the high dimensional setting is still incomplete, although many remarkable findings have been made. This dissertation presents some recent results on analyzing regularized regression in high dimensions, organized in three main strands:(1) Exact asymptotic characterizations: We study two regularized regression algorithms. The first one is the sorted ℓ1 norm penalized estimator (SLOPE) for sparse regression. We establish an asymptotic separability property of the SLOPE estimator. This yields a precise characterization of SLOPE in high dimensions via a one-dimensional representation. The second one is the box-relaxation decoder for binary signal recovery. We show that under certain regime, the asymptotic distribution of the number of wrong bits converges to a Poisson law. A distinctive feature of the above results is that they are exact and free of unknown constants.(2) Optimal design: The exact performance characterizations enable a principled way of optimally designing the regularized regression algorithms to reach the fundamental performance limits. Based on our exact characterizations of SLOPE, we address the question about its optimal regularization. Our results reveal that finding the optimal regularization in high dimensions is equivalent to solving an optimal denoising problem in one dimension. This turns out to be an infinite-dimensional convex problem, which can be solved efficiently.(3) Universality: It has long been observed that diverse high-dimensional probabilistic systems can share universal macroscopic behavior irrespective of their distinct detailed distributions. This universality phenomenon allows us to analyze some complicated models by establishing their equivalence to other simpler models. We prove a universality conjecture that has been utilized to study the learning performance of regularized regression in random feature model.More broadly speaking, these three strands are interwoven: universality makes the precise characterization, usually obtained in ideal theoretical models (e.g., i.i.d. Gaussian ensemble), be applicable to broader realistic models (e.g., tight frames) and eventually, the exact and universal characterizations enable the systematic way of optimally design the algorithms for various large-scale systems.

Shape-Morphing Dielectric Elastomer Devices

Hajiesmaili, Ehsan Harvard University ProQuest Dissertations & Theses 2022 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Dielectric elastomer actuators (DEAs) provide fast and reversible actuations with power and energy densities that are akin to natural muscles and high energy efficiencies compared to other soft actuators. Their actuation modes, however, have been limited to linear and bending, limiting their applications to devices with simple modes of deformations. This thesis presents methods for creating shape-morphing dielectric elastomer actuators and devices to produce complex out-of-plane deformations for applications such as biomimicry of swimming and flying locomotion and haptic displays.Morphing a flat sheet into a three-dimensional shape requires spatial distribution of the deformation, varying along the surface of the sheet. Two shape-morphing mechanisms for dielectric elastomer actuators are introduced in this thesis: one is based on creating spatially varying internal electric fields determined by the overlapping of adjacent electrodes in a multilayer DEA, and the other is based on creating spatially distributed anisotropic actuations whose local actuation directions are determined by patterns of incorporated stiff rings. Morphing into simple shapes such as cones, hemispherical caps and saddles are demonstrated.To produce more complex target shapes, solution to the inverse problem of design is required to determine the design of the actuators that morph into desired target shapes when actuated. The two shape-morphing methods based on the design of the electrodes and patterned stiff rings are combined to enable local control of both actuation magnitudes and directions, resulting in a simple analytical solution to the inverse problem. Morphing into complex target shapes such as a human face is demonstrated. To create shape-morphing DEAs that can be reprogrammed to morph into a variety of shapes on demand, arrays of DEAs are created and addressed using projected lights. This is enabled by integrating percolating networks of semiconducting nanoparticles into the design of the electrodes, and further opens the design space for DEA-based devices. Example of a wearable haptic device is demonstrated and methods for localization of optical addressing and mechanical actuations are presented.

Evaluating strategies for achieving global collective action on transnational health threats and social inequalities

Hoffman, Steven Justin Harvard University ProQuest Dissertations & Theses 2015 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

This dissertation presents three studies that evaluate different strategies for addressing transnational health threats and social inequalities that depend upon or would benefit from global collective action. Each draws upon different academic disciplines, methods and epistemological traditions. Chapter 1 assesses the role of international law in addressing global health challenges, specifically examining when, how and why global health treaties may be helpful. Evidence from 90 quantitative impact evaluations of past treaties was synthesized to uncover what impact can be expected from global health treaties, and based on these results, an analytic framework was developed to help determine when proposals for new global health treaties have reasonable prospects for yielding net positive effects. Findings from the evidence synthesis suggest that treaties consistently succeed in shaping economic matters and consistently fail in achieving social progress. Chapter 2 builds on this work by evaluating a broad range of opportunities for working towards global collective action on antimicrobial resistance. Access to antimicrobials and the sustainability of their effectiveness are undermined by deep-seated failures in both global governance and global markets. These failures can be conceptualized as political economy challenges unique to each antimicrobial policy goal, including global commons dilemmas, negative externalities, unrealized positive externalities, coordination issues and free-rider problems. Many actors, instruments and initiatives that form part of the global antimicrobial regime are addressing these challenges, yet they are insufficiently coordinated, compliant, led or financed. Taking an evidence-based approach to global strategy reveals at least ten options for promoting collective action on antimicrobial access, conservation and innovation, including those that involve building institutions, crafting incentives and mobilizing interests. Chapter 3 takes this dissertation beyond traditional Westphalian notions of collective action by exploring whether new disruptive technologies like cheap supercomputers, open-access statistical software, and canned packages for machine learning can theoretically provide the same global regulatory effects on health matters as state-negotiated international agreements. As a first move, this third chapter presents a relatively simple maximum entropy machine-learning model that automatically quantifies the relevance, scientific quality and sensationalism of news media records, and validates the model on a corpus of 163,433 news records mentioning the recent SARS and H1N1 pandemics. This involved optimizing retrieval of relevant news records, using specially tailored tools for scoring these qualities on a randomly sampled training set of 500 news records, processing the training set into a document-term matrix, utilizing a maximum entropy model for inductive machine learning to identify relationships that distinguish differently scored news records, computationally applying these relationships to classify other news records, and validating the model using a test set that compares computer and human judgments. The chapter concludes by arguing that these findings demonstrate how automated methods can evaluate news records faster, cheaper and possibly better than humans -- suggesting that techno-regulating health news coverage is feasible -- and that the specific procedure implemented in this study can at the very least identify subsets of news records that are far more likely to have particular scientific and discursive qualities. (Abstract shortened by ProQuest.).

Boundary, Artefact, and Presence in Recent Work

Bean, James Harvard University ProQuest Dissertations & Theses 2022 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

This dissertation describes compositional techniques and theoretical background for works composed during my time at Harvard. Two compositions predating this time are provided for context, laying out the problems I seek to address in the works presented in the portfolio. While earlier works of mine focused on the interactions of the performers’ physicality, newer works shift the focus to the interaction of the performers, their instruments, and the acoustics of a given performing environment. Some new works employ electronic sounds which act to conceal and reveal components of the acoustic instruments’ sound and engage with the specifics of the acoustic space. Other works are orchestrated for acoustic instruments pushed to states of instability.

On My Watch: The Role and Responsibilities of American College Trustees

Johnson, Marc A Harvard University ProQuest Dissertations & Theses 2015 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

New waves of change are upon American colleges and universities. Among other things, shifts in student demographics, federal higher education policy changes, and the continuing rise of new education providers are putting pressure on institutions to adapt in order to ensure their effectiveness and, in some cases, survival. The imperative to adapt to change is not new for American colleges and universities. Since the founding of the colonial colleges, the nation's institutions have refashioned themselves over time in response to a dynamic environment---often with great success. Less obvious, however, is how institutions' internal actors perceive their role in managing change. Most notably, little research is available to shed light on whether and how trustees---an institution's only legal fiduciaries---view their responsibility for preserving and adapting elements of an institution's mission and identity in response to a shifting reality. This dissertation aims to extend what we know about trustees' responsibilities, including their responsibility for managing change. To meet this objective, I draw upon interview data that I collected from a sample of private college trustee board chairs (n=25). The conversations were loosely guided by three questions: 1) What are trustees' perceptions of "good" trusteeship? 2) When does change to an institution's mission or identity become the focus of trustees' attention? 3) How do trustees make sense of decisions to preserve or adapt important aspects of an institution's mission or identity?. My findings suggest that trustees' perception of their responsibilities, including responsibility for managing change, generally align with historical definitions of trusteeship. I also identify three occasion types---Structural, Board, and Environmental---during which identity or mission change become a focus of trustees' discussions. Finally, I present an array of explanations and rationales that surface during our conversations about trustees' decisions to preserve or adapt an aspect of an institution's mission or identity.

Breath, Gravity, Giants, and Death: Puppet-Musical Encounters from Die Zauberflote to Today

Fenn, Hayley Alexandra Harvard University ProQuest Dissertations & Theses 2022 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Puppets are silent. But they are never apart from sound. In fact, they are immersed in it, entwined with it, inextricable from it. Prevailing definitions of the puppet allow its sounds to go unheard, rendering puppetry a vehicle of primarily visual expression. In this dissertation, by contrast, I redefine puppets musically. For not only does puppet performance generate considerable accidental sound, but intentional sound—voice, sound effects, and music—is crucial to the perception of the puppet as such. While music is the primordial sound that brings the puppet to life, moreover, sensibilities of music-making structure the phenomenology of puppetry. This dissertation argues that puppets are made legible through intentional sound, and that by careful analysis of their entwinement with music—a process that necessarily encompasses both archival and ethnographic methodologies—something we might call the puppet’s “inherent musicality” is revealed. Focusing especially on the puppetry of German-speaking lands, I propose Mozart’s Die Zauberflote (1791) as an originary work in a shared history of puppetry and music. Accordingly, the first half of this dissertation examines the ways in which Die Zauberflote conjures the specter of the puppet in three different settings: in musicological and philosophical discourse (Chapter One), in opera houses (Chapter Two), and in puppet theaters (Chapter Three). Together these chapters not only present the various ways in which puppets proliferate in and around Mozart’s last opera, but also lay the critical groundwork for analysing puppet-musical encounters. I introduce the concept of “the performance network” as both a model and methodology for taking account of the various performers, performing objects, performance histories and practices, and performance styles involved in puppet performance—including, most importantly, the puppets themselves and any musical provision. Negotiating the network produces characteristic aesthetics, which imbue a puppet with its own specific sensibility and a performance with a particular effect: a sense of performative freedom and aesthetic possibility that I describe using the phrase “the poetics of synchronization.”The second half of the dissertation consists of two case studies. In Chapter Four, the performance network(s) of Marionettentheater, or marionette opera, are analyzed through the lenses of puppetry’s most significant musical parameters: voice, movement, scale (i.e. miniaturization and gigantification), and silence. Chapter Five scrutinizes a single dyad within the broader performance network of the puppetry of the German polymath Richard Teschner (1879–1948): namely the relationship between his unique rod-and-string puppets, on the one hand, and the primary source of music for his plays, the Polyphon, a commercially manufactured quasi-gramophone, on the other. These performing objects embody various material and aesthetic oppositions, and as a pair, they make manifest the mutually constitutive nature of puppetry and music.In the Epilogue, I reflect on an artistic medium that reverberates throughout this dissertation: cinema. Puppets have long been an essential component of the cinematic toolkit, not least because through the mediating camera lens they can perform feats far beyond the capabilities of human actors. In the stop-motion silhouette animations of Lotte Reiniger (1899–1981), puppets are not only the actors, but the scenery too, navigating a one-of-a-kind performance network that makes concrete in compelling ways the phenomenon of audio-visual synchronization. Music, in my analysis, emerges as the answer to the question that has long dominated the scholarly literature: what makes a puppet? And my dissertation addresses a related question: why that matters. By revealing the “inherent musicality” of the puppet, I read puppetry back onto music and consider the puppet as an analytic lens for musical performance, musical technologies, and music history. Ultimately, by attending to the sonic capacities, expressions, and affordances of puppetry, I engage the age-old questions of music’s ineffability and its capacity to represent.

Evolution of parasitism in the Lycaenidae (Lepidoptera)

Kaliszewska, Zofia Adelajda Harvard University ProQuest Dissertations & Theses 2015 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

In this dissertation, I explore the ecological and evolutionary consequences of entomophagy in the butterfly family Lycaenidae using several approaches: natural history observation, phylogenetics, population genetics and stable isotope chemistry. A striking exception to the lack of radiation and persistence in aphytophagous lineages is the lycaenid subfamily Miletinae, which with 13 genera and 190 species is among the largest and most diverse groups of aphytophagous Lepidoptera. Most miletines eat Hemiptera, although some consume ant brood or are fed by trophallaxis from their host ant. I inferred the higher-level phylogeny of this group using data from one mitochondrial and six nuclear genes sampled from representatives of all genera and nearly half the described species. Biogeographic analyses indicate that Miletinae likely diverged from an African ancestor near the start of the Eocene, and four lineages dispersed between Africa and Asia. Phylogenetic constraint in prey selection is apparent at two levels: related miletine species are more likely to feed on related Hemiptera and are also more likely to associate with closely related ants species, either directly by eating the ants, or indirectly by eating hemipteran prey attended by those ants. I then examined the influence of diet on the population structure of lycaenid butterflies, and more specifically, I investigated whether particular feeding habits are correlated with traits that might make species vulnerable to extinction. To do this, I compared the phylogeography and population genetics of two endemic lycaenid species of roughly similar age from southern Africa: Chrysoritis chrysaor, whose caterpillars are strictly herbivorous, and Thestor protumnus, whose cuckoo-like caterpillars survive by soliciting regurgitations from their host ants. I sampled both species from populations throughout their entire known ranges, and found that in contrast to C. chrysaor, T. protumnus has exceedingly small effective population sizes and individuals disperse poorly. With its aphytophagous life history, T. protumnus exhibits a high degree of host dependence and specialization. Although these results are correlative and based on only a single comparison, it seems likely that small population sizes and extreme ecological specialization make populations of T. protumnus more susceptible to disturbance and prone to extinction. Having focused in detail on the population biology of just one species, I then analysed the evolution of Thestor as a whole. This genus is exceptional because all of its 27 described species are thought to be entomophagous, and all are thought to be predators or parasites of a single species of ant, Anoplolepis custodiens. Using representatives sampled from all known species and populations of Thestor as well as 15 outgroup species, I inferred the phylogeny of the genus in two ways: first by using characters from mitochondrial and nuclear genes, and second by analyzing genome-wide SNPs generated for each species using double digest RADseq. I also sequenced the ants associated with each of these taxa using ddRADseq. This investigation showed that all 24 of the species in the Western Cape utilize Anoplolepis custodiens, while T. protumnus and T. dryburghi (the two species that are found in the north-western part of South Africa) use a closely related, but different species of Anoplolepis, and T. basutus (the species found in the eastern part of South Africa) utilizes yet a third species. Thus factors driving diversity in the genus Thestor may have initially involved ant associations and/or geographic isolation, but other forces are likely to be responsible for generating and maintaining the more recent diversity in the group. Flight time may have separated the "black" and "yellow" groups of Thestor: the black group fly predominantly in the summer months, while the yellow group fly predominantly in the spring. And while species spread across the genus fly in the spring and summer months, only members of the yellow group fly during the winter and fall months. Despite these broad scale differences, species in the genus Thestor show little evidence of niche partitioning, especially those in the Western Cape, and represent an extreme example of the coexistence of 24 species apparently utilizing a single food resource. While working on the previous three projects, I was surprised by the number of species of South African Lycaenidae with incomplete life histories despite decades of work by avid lepidopterists in the region. To deepen our understanding of South African lycaenid life histories, I used nitrogen and carbon stable isotopic methods to survey a large number of species and their potential food sources. (Abstract shortened by ProQuest.).