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THE GHOST OF SLAVERY EXORCISED ONCE AND FOR ALL: ROMANTIC NATIONALISM AND WHITE BLINDNESS IN HERMON ATKINS MACNEIL’S CIVIL WAR SOLIDERS AND SAILORS MEMORIAL
Get PDFThe plethora of monuments produced in the late 19th and early 20th centuries, a phenomenon dubbed ‘statue mania’ by the scholar Erika Doss, continue to vex today. Removed from original time and context, they can provoke wildly variant readings or simply elude notice altogether, hidden in plain sight. Using various lenses, including urban planning, art history, and the dynamics of memory and history in the half century following the Civil War, this thesis seeks to demonstrate the value of analyzing these everyday monuments. This is done through close and thick examination of one case study: the Civil War Soldiers and Sailors Memorial in Philadelphia, PA. The ensuing analysis argues that the monument, designed by the sculptor Hermon Atkins MacNeil, celebrates a glorious vision of American virtuousness and heroism by framing the conflict of the Civil War and the abolition of slavery as a moment when the nation truly emerged as its ideal self, worthy of the heroic status afforded to it after World War I. Through this case study, this thesis seeks to understand the ideology behind the commission and placement of the monuments of statue mania to aid both the public and municipalities in future decisions related to management and preservation with a more robust interpretive framework. It works upon strong pre-existing literature to do so but seeks to address a couple of major gaps. These include a lack of scholarship addressing Unionist monuments and scant coverage of the context of urban planning design principles as crucial context for monuments. After surveying nearly three decades of the monuments’ path from planning to fruition, the analytic core of the thesis begins with the latter gap by examining the monument as part of the broader City Beautiful Movement and the landscape of the Benjamin Franklin Parkway, where the two pylons composing the monument operated as a frame for the great canvas of civilization, progress, and glory found in Philadelphia’s great urban planning experiment. Next, the thesis examines Hermon Atkins MacNeil’s past work as an artist, which sought to humanize his indigenous subjects while still vindicating American conquest as a result of the forces of destiny. This notion of an exceptional American destiny later finds voice in Soldiers and Sailors. Then the thesis contrasts Soldiers and Sailors with its primary inspiration, Paris’ Arc de Triomphe, and their shared theme of romantic nationalism. Finally, the issues of Civil War memory are further expounded upon, particularly regarding race and the broader trends of sectional reconciliation. In Soldiers and Sailors, the issue of slavery is central, but what is ignored is what is at stake for Black Americans both during and after the war, as these sordid histories are inconvenient to MacNeil’s triumphal narrative. The thesis concludes by examining the implications of the analysis, arguing that it reveals the central problem of monuments: they are intended for public consumption, yet historically have been utterly lacking in any avenue for meaningful public participation. While it is never clean or easy, increased democratic participation and a greater potential for the public to be actively involved with the creation of new monuments can create a richer culture of monuments, attending to the breadth and depth of history rather than the comforting narratives of the powerful
Responsive Math Teaching Model
Get PDFThe Responsive Math Teaching (RMT) Model breaks high-quality math teaching down into six core components: Plan: Select or adapt an appropriate task, identify the mathematical goal(s), and anticipate possible solution paths and challenges. Launch: Set up the task so that students understand the problem and can access the important mathematics. Facilitate productive struggle: Support students to engage in authentic problem solving. Discuss learner thinking: Facilitate the sharing of student strategies and reasoning and engage students in making sense of each other’s thinking. Return to mathematical goal: Guide students to make explicit connections between strategies and solutions and the key mathematical ideas. Reflect: Reflect on pedagogical and learning goals to determine next steps
The Shame Framework: Queer Faith in Ana Castillo’s So Far from God
Get PDFThis work focuses on queer faith and how queer persons who have struggled with traditional values, public opinion, and lingering violence due to their sexuality, can reclaim their space and voices within religious communities. By redefining purity, exploring an alternative belief system though hybrid spirituality, and understanding the connection between pride and shame, queer persons can establish a dynamic framework, that allows for queer faith to be employed as a method of agency. This is analyzed through a literary perspective, focusing on the work of Ana Castillo’s novel, So Far From God
The Butcher and the Arson: How Spain’s Generals Lost Her Empire and Destroyed Her Crown Jewel
Get PDFCorporate Limitarianism
Get PDFIngrid Robeyns argues that there is a point at which increasing one’s income no longer increases one’s quality of life. Her argument states that given better uses for this money, namely restoring political equality and meeting urgent needs, it is morally wrong for individuals to have surplus money, which is money beyond that which is needed to live a good life. Therefore, Robeyns argues that surplus money should be taxed at a rate of 100%. The original argument only applies to individuals with excess wealth. However, there is no reason why it should be restricted only to people. In Citizens United v. Federal Election Commission, the United States Supreme Court ruled that corporations have free speech rights, building on previous cases that gave corporations protection under the Fourth, Fifth, Seventh, and Fourteenth Amendments. Given that corporations have rights similar to people, should they be held to the same consideration of surplus economic value? Just as Robeyns argues that super-rich individuals have surplus money, so do mega-corporations have wealth beyond their use. I call this argument “corporate limitarianism”. In this paper, I apply Robeyns’ arguments for economic limitarianism, namely the democratic argument and the argument from unmet needs, to corporations. In the case of urgent needs, I also look at the expanded causal role of mega-corporations in creating and contributing to these issues and how it supports the corporate limitarianism argument
Extended Minds: The Externalization and Expansion of Human Minds Beyond the Body
Get PDFDespite the commonly accepted notion that the mind is inseparable from the body, the extended mind hypothesis claims human minds can become linked with the world around us. Through various avenues such as spoken and written language, humans may use non-biological means to allow the mind to store, access, and communicate information in extended capacities not otherwise possible. Though the extended minds hypothesis may be viewed as a result of advancing technology, it makes up only a small part of the way in which externalization may occur. Everyday life is full of examples of extended minds, from computers and phones to billboards and books. There is much debate among philosophers over the acceptance of the hypothesis, but in this paper, I will explore some of the most relevant arguments and aim to show why I hold the extended minds hypothesis to be true
Study of Metal Catalysts Supported on Thin Films of Perovskites Prepared by Atomic Layer Deposition (ALD)
No full textSintering is a severe problem for supported-metal catalysts in high-temperature applications, such as in automotive-emissions control, because it leads to a loss of catalytically active surface area. To stabilize the metal particles, in 2001, the Daihatsu group proposed using perovskite-supported metals, which they referred to as “intelligent” catalysts. The original goal was to regenerate sintered metals by driving the metal into the oxide lattice by high-temperature oxidation and releasing the metal as small particles by reduction. Unfortunately, the concept has not been entirely successful, partially because of the large crystallite size and low surface areas of typical perovskites. To achieve higher surface areas and reduce the length scale for any ingress-egress of metal particles, Atomic Layer Deposition (ALD) was used in this thesis to prepare thin films of perovskites on high-surface-area supports. These ALD films were shown to be uniform and thermally stable under high-temperature operating conditions. Metal catalysts, Pt, Ni, Pd, and Rh, were deposited onto the perovskite thin films, LaCoO3 and LaFeO3, using ALD. The catalysts exhibited several key properties similar to bulk “intelligent” catalysts. First, the metal particles could be stabilized by the perovskite films under high-temperature conditions. Second, the ALD platinum-group metal catalysts showed self-regenerative activity in CO oxidation upon oxidation and reduction at high temperatures. Third, like the Ni ex-solved from bulk perovskite materials, Ni supported by ALD perovskite films showed superior coking resistance towards methane. The metal particles in this thesis were likely very different from bulk intelligent catalysts because the film thickness was much smaller than the metal particle size. To understand their behaviors, this thesis focused on studying metal-perovskite interactions in the ALD samples of metals supported on LaFeO3 films. It was found that metal-perovskite interactions could dramatically affect the preferential alignment of metal particles with the substrate, the metal dispersions, and catalytic activity. In the presence of the perovskite films, the equilibrium oxidation of the metals could also shift several order-of-magnitudes towards lower PO2. The changes in the thermodynamic properties would further cause different catalytic behaviors. Systems of different metals supported on LaFeO3 films were studied and compared; it was found that the metal-perovskite interaction is specific for each system
Metabolic Reprogramming Steers Stem Cell Evolution
Get PDFRemarkable plasticity of stem cells endows them with the ability to adapt quickly to ever-changing niches throughout a lifetime by reprogramming their metabolism and function. Upon sensing environmental challenges and following intrinsic genetic programs, rapidly proliferating progenitor cells during early postnatal development rewire their metabolic program to convert into quiescent somatic stem cells for lifelong tissue homeostasis. The molecular switch controlling this stem cell fate conversion is still obscure. Here we show that neonatal mesenchymal stem/progenitor cells (nMSCs) exhibit robust stem cell activity with higher proliferation and multilineage differentiation potential than adult MSCs (aMSC). The functional robustness of nMSCs requires peroxisome proliferator-activated receptor-gamma coactivator-1α (Pgc-1α)-mediated oxidative phosphorylation (OxPhos) as the metabolic switch which is turned off in aMSCs. The cell fate conversion between nMSCs and aMSCs by the Pgc-1α-OxPhos switch is regulated by octamer-binding transcription factor-4 (Oct-4) which directly binds to the Pgc-1α promoter and induces the promoter activity. The failure to flick on the metabolic switch by deleting Pgc-1α in nMSCs impedes normal craniofacial growth and development. By studying stem cells in perinatal transition, these findings underscore the importance of precise metabolic control of stem cell function to support the life-stage-specific roles of stem cells during craniofacial development and homeostasis. Based on the newly identified mechanism, this study will improve our understanding of stem cell evolution processes and will define a novel metabolic switch to improve stem-cell-based craniofacial tissue regeneration
An in Situ Study of Resistance Degradation and Switching of Bulk Yttria-Stabilized Zirconia and Strontium Titanate Single Crystals
No full textUnderstanding resistance changes under a constant or set of bipolar-switching voltage(s) is important for thin-film devices, specifically multilayer capacitors and resistance-switching memory. However, identifying critical locations of changes and failures in thin films is difficult, so this work studies the same phenomena in single crystals of yttria-stabilized zirconia (YSZ) and iron-doped strontium titanate (STO) starting with highly accelerated lifetime tests (HALT) at higher temperatures. Although doped STO is a p-type semiconductor and YSZ a fast oxygen-ion conductor with little electronic conductivity, their DC resistance-degradation curves are remarkably indistinguishable. Yet different mechanisms were revealed by in-situ hot-stage photography and thermal imaging in two test environments—air and silicone oil. In YSZ, DC (electro)reduction does not appreciably alter oxygen stoichiometry; nevertheless, above a threshold voltage, it can raise the chemical potential of electrons to the conduction-band level, thereby triggering a metal-insulator (resistance) transition. In contrast, DC-stressed STO undergoes oxygen-vacancy demixing, forming a p-n junction with elevated electronic conductivity, albeit late-stage-demixing can be so sluggish that the steady state is difficult to reach in low-temperature HALT. In both oxides, an inherent instability in the governing field equation dictates degradation follows filament-like paths, which explains the strong field dependence and large variation of lifetimes. Upon further voltage reversals, degraded crystals exhibit different, large resistance changes. In YSZ, a change in DC voltage can already cause a resistance change, which is unipolar switching. But additional resistance degradation after voltage reversal can facilitate filament fragmentation, thus rendering the crystal bipolarly switchable due to a voltage-sensitive metal-insulator transition in a thin layer of barely metallic YSZ adjacent to the original anode. In STO, voltage reversals broaden/narrow a nanolayer of stoichiometric, ionic STO (called i-region) that straddles the p-n junction, by driving electromigration to act in-concert/against back-diffusion of oxygen ions. Thickening/thinning of such region leads to resistance increase/decrease, resulting in the so-called eightwise” bipolar switching. (Interface-controlled, “counter-eightwise” switching was also observed in more severely degraded STO.) As these phenomena find analogies in thin-film devices, mechanisms revealed above have provided new insight that will help understand and improve the performance and reliability of engineering devices
Experimental Methods to Support Robot Behavior Design for Legged Locomotion on Granular Media
No full textMost models of legged locomotion assume a rigid ground contact, but this is not a reasonable assumption for robots in unstructured, outdoor environments, and especially not for field robots in dry desert environments. Locomotion on sand, a highly dissipative substrate, presents the additional challenge of a high energetic cost of transport. Many legged robots can be adapted for desert locomotion by simple morphological changes like increasing foot size or gearing down the motors. However, the Minitaur robot has direct-drive (no gearbox) legs which are sensitive enough to measure ground properties of interest to geoscientists, and its legs would lose their sensitivity if they were geared down or the foot size increased substantially. This thesis has two main contributions. First, a controller for jumping on sand with a direct-drive robot that saves significant energy in comparison to a nominal compression-extension Raibert-style controller without sacrificing jump height. This controller was developed by examining the complex interaction between the jumping leg and the ground, and devising a force to add to the leg controller which will push the robot’s foot into a more favorable state that does not transfer as much energy to the ground. The second contribution is a ground emulator robot which can be programmed to exert ground force functions of arbitrary shape. With the ground emulator, it is possible for a robot on a linear rail to jump dozens of times per experiment, whereas traditional experiments on granular media would require the ground to be reset between individual jumps. Results from the simulation experiments used to develop the controller and the ground emulator experiments used to test it on a physical robot leg are validated with experiments on a prepared granular media bed. Finally, the contributions of this thesis are contextualized in a broader project of building explainable artificially intelligent systems by composing robust, mostly reactive controllers