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Control of chloroplast movement in epidermal pavement cells is dependent on CHUP1 and the cytoskeleton
No full text"At the request of the author or degree granting institution, this graduate work is not available to view or purchase until August 31 2026"--ProQuest citation/abstract page.Song, Jia L.Caplan, Jeffrey L.Chloroplasts are a critical element for maintaining plant health. They are involved in countless cellular processes, from cellular stress responses, light-based responses, and even innate immunity. Additionally, chloroplasts have tubular extensions called stromules that have been linked to transmission of chloroplast generated signals. Despite stromules being implied to have a role in the transmission of vital chloroplast generated signals, they have not been heavily studied as to how they relate to chloroplast movement, or how stromules movement itself is regulated. In this dissertation, we found that stromules are significantly influenced by the cytoskeletal elements, and more specifically that their dynamism depends on the state of the microtubule filaments. Through stabilizing microtubules by silencing γ -Tubulin Complex Protein (GCP4), leading to bundling, we are able to observe a change in stromule dynamics that is directly tied to the changes in the microtubule filaments (MT). Additionally, we found that there is a clear connection between chloroplast movement and stromules by identifying a form of epidermal chloroplast movement called stromule directed movement (SDM), as well as establish a stromule analysis pipeline allowing for the collection of far greater and far more accurate measurements of stromule characteristics. ☐ Chloroplast unusual positioning 1 (CHUP1) is a chloroplast outer membrane protein that has been shown to be associated with chloroplast movement. Most significantly, CHUP1 has been shown to play a major role in chloroplasts binding to the plasma membrane, as well as being required for proper chloroplast positioning and light mediated movement in mesophyll cells. It is even thought that CHUP1 might be a source of motive force for chloroplast movement, through its interactions with chloroplastic actin (CP-actin). The hypothesis that was tested in the work of this dissertation was that CHUP1 acts as a negative regulator of chloroplast movement, and that silencing CHUP1-independently alters stromule and chloroplast movement dynamics. In addition, this work found that examination of epidermal chloroplasts allows for a broader and more complete understanding of chloroplast movement dynamics, stromule movement dynamics, as well as examining the function of proteins that have already been heavily studied in the mesophyll. This is supported by showing that in epidermal chloroplasts, CHUP1-silencing amplifies chloroplast movement, which is not the case in mesophyll chloroplasts. Additional work was done to show that CHUP1-silencing amplifies Reactive Oxygen Species (ROS), which induces stromules and amplifies effector-triggered immunity (ETI), but is not responsible for the changes in stromule or chloroplast movement dynamics caused by CHUP1-silencing. The results of this work show that CHUP1-silencing amplifies stromule and chloroplast responses that are associated with effector-triggered immunity. Furthermore, this works shows that that blue light mediated movement still occurs in epidermal chloroplasts, and shows that PHOTOTROPIN1 (PHOT1) might play a role in the regulation of stromules, while also functioning independently of CHUP1. ☐ With those results and more, I show that examining chloroplast dynamics only in the context of a single cell type leads to a limited understanding, and that by examining across various cell types, in which behaviors and cellular conditions might change, we are able to reveal new possibilities that will expand our understanding even further.University of Delaware, Department of Biological SciencesPh.D
Constructivity conditions on immune sets
No full textThis article was originally published in Archive for Mathematical Logic. The version of record is available at: https://doi.org/10.1007/s00153-024-00958-x.
© The Author(s) 2024.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Definitionally: strongly effectively immune sets are infinite and their c.e. subsets have maximums effectively bounded in their c.e. indices; whereas, for effectively immune sets, their c.e. subsets’ cardinalities are what’re effectively bounded. This definitional difference between these two kinds of sets is very nicely paralleled by the following difference between their complements. McLaughlin: strongly effectively immune sets cannot have immune complements; whereas, the main theorem herein: effectively immune sets cannot have hyperimmune complements. Ullian: effectively immune sets can have effectively immune complements. The main theorem improves Arslanov’s, effectively hyperimmune sets cannot have effectively hyperimmune complements: the improvement omits the second ‘effectively’. Two natural examples of strongly effectively immune sets are presented with new cases of the first proved herein. The first is the set of minimal-Blum-size programs for the partial computable functions; the second, the set of Kolmogorov-random strings. A proved, natural example is presented of an effectively dense simple, not strongly effectively simple set; its complement is a set of maximal run-times. Further motivations for this study are presented. Kleene recursion theorem proofs herein emphasize how to conceptualize them. Finally, is suggested, future, related work—illustrated by a first, natural, strongly effectively -immune set—included: solution of an open problem from Rogers’ book
Hyperspectral image analysis via subspace clustering
No full textHong, DavidRadpour, RoxanneThis thesis studies Hyperspectral Image Analysis using various unsupervised learning techniques with a special focus on Subspace Clustering methods. Hyperspectral imaging captures images across numerous (up to hundreds) narrow, overlapping wavelength bands, enabling each pixel in the spatial scene to have a high spectral resolution signature, producing a data-rich, high-volume 3D image cube. However, the high-dimensional nature of the data poses challenges in terms of data processing and analysis. This can be addressed through subspace clustering methods which provide a robust approach for uncovering low-dimensional structures lying in a high-dimensional feature space. This thesis first evaluates different classification methods such as Mean-based classification, Subspace-based classification, and Affine space-based classification. Next, a detailed investigation is performed into several clustering techniques such as K-Means, K-Subspaces, K-Affine spaces, and Threshold Subspace Clustering. Subspace clustering techniques are particularly highlighted in this thesis as they are known for capturing the underlying geometric structure of data points, enabling meaningful clustering even in cases where data points are far apart in high-dimensional spaces but lie on the same subspace. This comprehensive study provides insights into how data from different fields utilizing hyperspectral imaging, including benchmark datasets like Pavia Centre Scene, Pavia University Scene, Salinas Scene, and the Egyptian Blue Test Panel, respond to these methods, paving the way for further advancements in the field of hyperspectral image analysis.University of Delaware, Department of Electrical and Computer EngineeringM.S
Documenting War Crimes Onstage in Kyo Choi’s The Apology
No full textThis article was originally published in Humanities Bulletin. The version of record is available at: https://journals.lapub.co.uk/index.php/HB/article/view/2917.
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License (https://creativecommons.org/licenses/by-sa/4.0/).This essay discusses Kyo Choi’s play The Apology, which was first produced in London in 2022, as an example of activist theatre, meant not only to educate British audiences about the ongoing controversies over the so-called “comfort women” issue, involving Japanese military sexual slavery during World War II, but to move viewers to action. Choi’s drama does so through a form of emotional documentation, which supplements and amplifies actual documents related to this war crime
Convolutional neural networks for radio signals from cosmic-ray air showers
No full textSchroeder, Frank G.The interaction of high-energy cosmic rays from outer space with the Earth’s atmosphere produces cascades of particles known as extensive air showers (EAS). These EAS emit radio signals, primarily due to the time variation of transverse currents, which result from the deflection of electrons and positrons in the geomagnetic field. These impulse radio signals can be captured by antennas and used to reconstruct EAS properties, such as energy and the depth of shower maximum, Xmax. However, natural radio background from galactic sources and man-made radio frequency interference (RFI) significantly limit radio detection capabilities. ☐ To address this challenge, machine learning techniques, specifically convolutional neural networks (CNNs), are utilized in this work to identify and denoise radio signals. The CNNs are trained using simulated radio signals combined with measured radio background noise from antennas at the South Pole. These antennas are part of a surface enhancement planned for IceCube, which involves adding stations with scintillator panels and radio antennas to the existing IceTop array. The results show that CNNs significantly improve the accuracy of pulse power and arrival time reconstruction, particularly at low and intermediate signal-to-noise ratios (SNR). Once trained, the CNNs were applied to search for EAS radio events. The CNNs demonstrated significant improvements over a standard method, which relies on a SNR cut. Using CNNs, approximately five times more events were identified compared to the standard method, and the false event rate was also significantly reduced.University of Delaware, Department of Physics and AstronomyPh.D
Urban heat island (UHI) development and mitigation measures in three Bangladesh cities: Dhaka, Chattogram, and Sylhet
No full textDeLiberty, Tracy L.The surge in urban population worldwide has led to a swift expansion of urban areas and noticeable temperature differences between urban centers and their rural surroundings. This phenomenon, known as the Urban Heat Island (UHI) effect, is increasingly recognized as a significant human impact on the environment with both local and global consequences. The rapidly expanding populations in Asian cities, including Bangladesh cities, are anticipated to be highly susceptible to these impacts. Although the UHI effect has been extensively studied in both large and medium-sized cities globally, comparative research on rapidly developing Bangladesh cities remains sparse. The study compares the UHI development in the three largest cities of Bangladesh that includes Dhaka, Chattogram (previously known as Chittagong), and Sylhet, after documenting the changes in land use patterns in the current municipal boundary and proposed future extension areas over the last two decades. The research also integrates uncertainty maps to specify the confidence levels in land use classification results that are not prevalent in prior studies. Additionally, most existing studies have relied solely on satellite data to analyze the land surface temperature (LST) to quantify the surface urban heat island (SUHI), often overlooking the atmospheric urban heat island (AUHI). This study combines in-situ measurements (AUHI) with remotely sensed data (SUHI) to assess the spatiotemporal variability of the city's microclimate. The dew point temperature was computed in conjunction with temperature to enhance the understanding of heat stress conditions. Along with evaluating the temperature and dew points trends over the twenty year period, their statistical significance was computed using the Mann-Kendall test and the t-test performed to determine if the urban and rural time series were distinct. The final step of this study investigated the UHI mitigation measures addressed in each city’s future development plans to reduce urban warming effects by increasing green spaces (such as parks, rooftop gardens, and vertical green walls) and blue spaces (such as rivers, ponds, and lakes). Effective mitigation strategies most appropriate for each city’s urban context were highlighted to help urban planners and policymakers take immediate action to reduce the adverse impacts of UHI and ensure sustainable and livable urban environments.University of Delaware, Department of Geography and Spatial SciencesPh.D
Assessing the 1921–1922 federal financial rescue: the War Finance Corporation Bank lending program
No full textThis article was originally published in Financial History Review. The version of record is available at: https://doi.org/10.1017/S0968565024000131.
Copyright © The Author(s), 2025. Published by Cambridge University Press on behalf of the European Association for Banking and Financial History.
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.The 1920–1 recession did not transpire entirely without federal intervention, as commonly believed. Following lending by several Federal Reserve banks, the federally chartered War Finance Corporation (WFC) lent to support exports and shortly after the recession, it lent aggressively to assist banks in agricultural regions, as numerous bank suspensions resulted from the agricultural depression of the early 1920s. Bank suspensions decreased markedly in 1922 to the lowest annual total during the 1921–33 period. This article assesses the impact of WFC lending on bank suspensions, and to what extent the WFC's provision of liquidity helped to resolve the existing difficulties
