Showing 221 - 230 of 317 Items
From American Dream to American Reality: The Effect of Educational Expenditures on Intergenerational Mobility and the Great Gatsby Curve
Date: 2022-01-01
Creator: Isabel Krogh
Access: Open access
- Income inequality and intergenerational mobility are two common measures of economic fairness in society. While they measure distinct ideas, they are significantly related in an inverse way across countries as well as across regions in the United States. This relationship is illustrated on the Great Gatsby Curve. Unequal access to education is one factor that has been found to drive the negative relationship between these two measures and therefore create the negatively sloping Great Gatsby Curve. Therefore, creating more equal access to education, such as through government spending, could lessen the connection between these two factors. The primary purpose of this research is to explore the effect of public educational expenditure on intergenerational mobility as well as on the slope of the Great Gatsby Curve. At the primary/secondary education level, this study finds that places with higher public spending on education tend to have higher levels of intergenerational mobility. However, no significant relationship is found between spending on tertiary education and intergenerational mobility. In addition, while higher primary/secondary educational spending is associated with a flatter Great Gatsby Curve at the school district level, these results were not consistent at the commuting zone level, so no strong conclusions can be made about the effect of public educational expenditures as a mediating factor of the Great Gatsby Curve.
Characterization of expression of Sema1a variants in high-plasticity areas of the Gryllus bimaculatus nervous system
Date: 2018-05-01
Creator: Sara Spicer
Access: Open access
- The well-conserved semaphorin family of guidance molecules is known to play multiple complex roles in directing the growth and orientation of dendrites and axons within the developing invertebrate central and peripheral nervous system. Additionally, the expression of select semaphorins is maintained within some highly plastic areas of the adult central nervous system, such as the mushroom bodies, where they are associated with guidance of newly-born neurons as well as with synapse formation and modification. Within the cricket species Gryllus bimaculatus, deafferentation of the prothoracic ganglia and subsequent dendritic rearrangement of the auditory interneurons is associated with fluctuations in the expression of transmembrane Sema1a and diffusible Sema2a. Here, we characterize the expression of two different variants of Gryllus Sema1a, termed Horch Sema1a and Extavour Sema1a, in tissues associated with both developmental neuronal guidance and adult structural plasticity: the embryonic limb buds, the mushroom bodies of the brain, and the non-deafferented adult prothoracic ganglion. Although we were unable to visualize the expression of Extavour Sema1a in any tissue, we demonstrate via phylogenetic analysis that both Sema1a variants have homologs in species across the Insecta class, suggesting that Extavour SEMA1a is a conserved protein sequence. We observe no expression of Horch Sema1a in the embryonic limb bud, and suspect that Extavour Sema1a, which has a high pairwise identity with Schistocerca Sema1a, could be facilitating guidance of the tibial pioneer neuron growth in the limb bud, along with Sema2a. In the adult brain, we observe a colocalization of Horch Sema1a and Sema2a in the mushroom bodies and in a vertical stripe across the calyx, which may be indicative of interactions between Horch SEMA1a and SEMA2a in maintaining synaptic plasticity and guiding newly-born Kenyon cells. We also report a colocalization of Horch Sema1a and Sema2a in the anterior and posterior of the prothoracic ganglia on the ventral side, in the region of auditory interneuron cell bodies, suggesting the possibility that auditory interneurons may express both Horch Sema1a and Sema2a, which could interact with each other or with Plexin receptors to regulate dendrite morphology at the midline.
The Scars of War: The Demonic Mother as a Conduit for Expressing Victimization, Collective Guilt, and Forgiveness in Postwar Japanese Film, 1949-1964
Date: 2017-05-01
Creator: Sophia Walker
Access: Open access
- Contemporary American viewers are familiar with the vengeful and terrifying ghost women of recent J-Horror films such as Ringu (Nakata Hideo, 1998) and Ju-On (Shimizu Takashi, 2002). Yet in Japanese theater and literature, the threatening ghost woman has a long history, beginning with the neglected Lady Rokujo in Lady Murasaki’s 11th century novel The Tale of Genji, who possesses and kills her rivals. Throughout history, the Japanese ghost mother is hideous and pitiful, worthy of fear as well as sympathy, traits that authors and filmmakers across the centuries have exploited. This project puts together four films that have never before been discussed together -- Kinoshita Keisuke's Shinsaku Yotsuya Kaidan (1949), Nakagawa Nobuo's Tokaido Yotsuya Kaidan (1959) Mizoguchi Kenji's Ugetsu (1953), and Shindo Kaneto's Onibaba (1964) -- and discusses them as four different iterations of the demonic mother motif, presented as a projection of the Japanese collective’s postwar uncertainty over both the memory of suffering during World War II and the question of personal culpability.
"Cooperate with Others for Common Ends?": Students as Gatekeepers of Culture and Tradition on College Campuses
Date: 2017-05-01
Creator: Pamela Zabala
Access: Open access
- As colleges and universities have increased efforts to make their campuses more racially and ethnically inclusive, students of color still perceive their campuses as hostile spaces to racial and ethnic minorities. On the other hand, white students often feel as though their institutions do too much, leaving administrators to balance the interests of both groups. This thesis draws on archival, ethnographic, and interview data collected at Bowdoin College to examine the relationship between students and between students and administrators given the role of students as major agents of change on college campuses. I have found that when students feel threatened by institutional change, they go into crisis and create spaces of resistance on campus. Institutions are incapable or unwilling to find solutions that meet the needs of the various constituencies within the student body. Therefore, students and administration become locked in a power struggle that produces only surface-level institutional change rather than meaningful reform in the face of rising racial tensions.
Examining the role of GRP and LIK1 in Wall Associated Kinase (WAK) perception of pectin in the plant cell wall
Date: 2017-01-01
Creator: Jack Ryan Mitchell
Access: Open access
- Wall associated kinases (WAKs) are cell membrane bound receptor kinases that bind pectin and pectin fragments (OGs).The binding of WAKs to pectin sends a growth signal required for cell elongation and plant development. WAKs bind OGs with higher affinity than native pectin and instead activate a stress response. Glycine rich proteins (GRPs) are secreted cell wall proteins of unknown function. Seven GRPs with 65% sequence similarity are coded on a 90kb locus of Arabidopsis chromosome 2. GRP3 and WAK1 have been shown to bind in vitro, but single null mutations have no discernible phenotype, suggesting that the GRPs are redundant. Low recombination frequency has made multiple mutations difficult to achieve, but in this thesis, CRISPR/Cas9 technology was used to induce deletions of the GRP locus. The promoters pYAO and pICU2 drove Cas9 expression in transformed Arabidopsis plants. The presence of a deletion and Cas9 were detected by PCR. While somatic mutations were induced, there was no inheritance of the GRP deletion, indicating that pYAO and pICU2 do not drive Cas9 to induce deletions in progenitor cells. LIK1 is a CERK1 interacting kinase implicated in mediating response to various microbe associated molecular patterns (MAMP) such as chitin, flagellin, and peptidoglycans. LIK1 exhibits a drastic increase in phosphorylation in response to OG treatment, making it a candidate for a co-receptor to WAK. T-DNA insertions to the 5’UTR of LIK1 were used to examine the effect of a lik1 mutation on the OG induced stress response. lik1/lik1 mutant seedlings were grown in the presence and absence of OGs, and RNA was isolated. qPCR was used on cDNA to examine FADLOX expression, a reporter for the transcriptional response to OGs. The lik1/lik1 mutant caused a reduction in the OG induced transcriptional response. However, increased LIK1 expression was associated with the T-DNA insertion indicating that LIK1 inhibits the WAK stress response pathway. Understanding the roles of GRP and LIK1 in moderating WAK mediated pathogenic response in Arabidopsis will enable a better understanding of plant resistance to pathogen invasion in the greater plant kingdom.
The Independent State Legislature Theory and Partisan Gerrymandering: How Moore v. Harper May Reshape Congressional Elections
Date: 2023-01-01
Creator: Luke Porter
Access: Open access
- In 2019, the U.S. Supreme Court ruled in Rucho v. Common Cause that partisan gerrymandering is not a justiciable question for federal courts. Four years later, the Court is reviewing a new case, Moore v. Harper. In Moore, the question presented is whether state courts can review partisan gerrymandering. The central question in Moore is the validity of the Independent State Legislature Theory. Proponents of the ISLT believe that state legislatures derive their authority to draw Congressional districts from the Federal Constitution and are therefore not subject to state-level checks and balances such as gubernatorial vetoes and state courts when redistricting. Critics argue that neither precedent nor the intent of the Framers grants state legislatures exclusive authority over redistricting. This paper analyzes the history of the Independent State Legislature Theory and outlines potential standards that the Court may adopt based off past-precedent. It then applies these standards to the redistricting process, arguing that nearly any form of the Independent State Legislature Theory would harm American democracy by making it easier for state legislatures to draw Congressional districts for partisan advantage. This paper concludes with strategies for mitigating the harm that would be caused if the Court legitimizes the Independent State Legislature Theory.
The Ethiopian Student Movement and the Dilemma of Eritrean Sovereignty
Date: 2024-01-01
Creator: Liat G. Tesfazgi
Access: Open access
- From the perspective of Ethiopian royalists, Pan-Africanists, Marxist internationalists, supports of union, and the broader international community, Eritrean nationalism revealed distressing fissures in many different arguments for preserving Ethiopian territorial unity– arguments not necessarily or explicitly problematic, but nevertheless in opposition to Eritrean demands for the right to national self-determination. For the Ethiopian Student Movement (ESM) specifically, Eritrean sovereignty demanded a reconfiguration of Pan-African unity that conflicted with Ethiopian exceptionalist historiography. Through an analysis of student politics at Haile Selassie University, from 1960-1974, this thesis seeks to complicate existing historiography on the ESM by examining the periodically divergent experiences of Eritrean student activists.
Neural compensation in response to salinity perturbation in the cardiac ganglion of the American lobster, Homarus americanus
Date: 2024-01-01
Creator: Josephine P. Tidmore
Access: Open access
- Central pattern generator (CPG) networks produce the rhythmic motor patterns that underlie critical behaviors such as breathing, walking, and heartbeat. The fidelity of these neural circuits in response to fluctuations in environmental conditions is essential for organismal survival. The specific ion channel profile of a neuron dictates its electrophysiological phenotype and is under homeostatic control, as channel proteins are constantly turning over in the membrane in response to internal and external stimuli. Neuronal function depends on ion channels and biophysical processes that are sensitive to external variables such as temperature, pH, and salinity. Nonetheless, the nervous system of the American lobster (Homarus americanus) is robust to global perturbations in these variables. The cardiac ganglion (CG), the CPG that controls the rhythmic activation of the heart in the lobster, has been shown to maintain function across a relatively wide, ecologically-relevant range of saline concentrations in the short-term. This study investigates whether individual neurons of the CG sense and compensate for long-term changes in extracellular ion concentration by controlling their ion channel mRNA abundances. To do this, I bathed the isolated CG in either 0.75x, 1.5x, or 1x (physiological) saline concentrations for 24 h. I then dissected out individual CG motor neurons, the pacemaker neurons, and sections of axonal projections and used single-cell RT-qPCR to measure relative mRNA abundances of several species of ion channels in these cells. I found that the CG maintained stable output with 24 h exposure to altered saline concentrations (0.75x and 1.5x), and that this stability may indeed be enabled by changes in mRNA abundances and correlated channel relationships.
Mathematical Modeling of the American Lobster Cardiac Muscle Cell: An Investigation of Calcium Ion Permeability and Force of Contractions
Date: 2014-05-01
Creator: Lauren A Skerritt
Access: Open access
- In the American lobster (Homarus americanus), neurogenic stimulation of the heart drives fluxes of calcium (Ca2+) into the cytoplasm of a muscle cell resulting in heart muscle contraction. The heartbeat is completed by the active transport of calcium out of the cytoplasm into extracellular and intracellular spaces. An increase in the frequency of calcium release is expected to increase amplitude and duration of muscle contraction. This makes sense because an increase in cytoplasmic calcium should increase the activation of the muscle contractile elements (actin and myosin). Since calcium cycling is a reaction-diffusion process, the extent to which calcium mediates contraction amplitude and frequency will depend on the specific diffusion relationships of calcium in this system. Despite the importance of understanding this relationship, it is difficult to obtain experimental information on the dynamics of cytoplasmic calcium. Thus, we developed a mathematical diffusion model of the myofibril (muscle cell) to simulate calcium cycling in the lobster cardiac muscle cell. The amplitude and duration of the force curves produced by the model empirically mirrored that of the experimental data over a range of calcium diffusion coefficients (1-16), nerve stimulation durations (1/6-1/3 of a contraction period), and frequencies (40-80 Hz). The characteristics that alter the response of the lobster cardiac muscle system are stimulation duration (i.e., burst duration), burst frequency, and the rate of calcium diffusion into the cell’s cytoplasm. For this reason, we developed protocols that allow parameters representing these characteristics in the calcium-force model to be determined from isolated whole muscle experiments on lobster hearts (Phillips et al., 2004). These parameters are used to predict variability in lobster heart muscle function consistent with data recorded in experiments. Within the physiological range of nerve stimulation parameters (burst duration and cycle period), calcium increased the cell’s force output for increased burst duration. For example, increased duration of stimulation increased the muscle contraction period and vice versa. In terms of diffusion, a slower rate of calcium diffusion out of the sarcoplasmic reticulum decreased both the calcium level and the contraction duration of the cell. Finally, changes in stimulation frequency did not produce changes in contraction amplitude and duration. When considered in conjunction with experimental stimulations using lobster heart muscle cells, these data illustrate the prominent role for calcium diffusion in governing contraction-relaxation cycles in lobster hearts.
Governing the Internet: The Extraterritorial Effects of the General Data Protection Regulation
Date: 2020-01-01
Creator: Sasa Jovanovic
Access: Open access
- The advent of the commercial Internet has introduced novel challenges to global governance because of the transnational nature of shared data flows, creating interdependence that may result in inter-state cooperation or competition. Data protection laws that are designed to ensure citizens’ right to privacy are one of the primary tool used by states to extend control over data flows. The European Union’s (EU) General Data Protection Regulation (2016) is widely regarded as the strongest data protection law in the world, and therefore may serve as a barrier to the openness of the Internet. The GDPR is both an instance of regulatory competition between the EU and US, but also heightens the need for cooperation to ensure the smooth functioning of online commerce. This paper shows that the EU is exporting the GDPR to jurisdictions such as the US via extraterritorial effects, even though the US has adopted an alternative legal approach to data protection. This paper seeks to explain the influence and limitations of the GDPR by considering factors such as the relative regulatory capabilities of the EU and the US as the result of their institutional and legal histories. It demonstrates that the EU has relied on complex interdependence to design a regulation like the GDPR, and it uses this regulatory competitive advantage alongside its soft power to promote its model of data protection, allowing the EU to obtain favorable outcomes in cooperation with the US.