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ScrollStats: An Automated Tool for Deciphering Meander Scrolls and Uncovering the Hidden Paths of Meander Migration
No full textScroll bars are arcuate, elongated landforms deposited along the inner banks of meandering rivers. This deposition occurs within zones of flow separation typically during discrete high-flow events. As the channel meanders, scroll bars are deposited successively in its wake and are preserved by stabilizing vegetation, leaving behind a well-preserved, visually intuitive migration history in the resulting ridge and swale topography (RST). Because of this episodic deposition, bar location and orientation can serve as a record for migration history while specific bar morphology can contain information about the hydrologic conditions under which the bar was deposited. ScrollStats is an open-source GIS tool developed to digitize and extract this morphological information from DEMs of the RST of meandering bends. ScrollStats produces two primary data products 1) migration pathways derived from preserved scroll bar location and orientation and 2) a ridge area raster delineating the ridge areas within the DEM. From these data products, ScrollStats calculates a suite of ridge morphometrics (ridge width, amplitude, and spacing) for every intersection of an identified ridge and migration pathway, covering the entirety of the bend's interior. In this paper, we showcase the capabilities of ScrollStats on a compound bend of the Lower Brazos River, Texas, USA. We also demonstrate how ScrollStats compares to other methods previously used to extract morphometrics from RST and how it can be used to expand upon previous findings in the literature. ScrollStats allows researchers to extract floodplain morphometrics previously unavailable, enabling new research into bend-scale migration dynamics and linkages between hydrologic process and the resulting landforms
���Let the Storm Begin!���: Ethnic Politics, German Americans, and the Mass Lynching of Eleven Italians in New Orleans, 1830-1899
No full textThis thesis argues elite German New Orleanians used the anti-Italian hysteria in New Orleans following Police Chief David Hennessy���s death in 1890 to promote their precarious social status among the elite White New Orleans native-born community. 1890 is only one year in the German community���s long endeavor to prove their status as members of elite White New Orleans society. Upon their arrival in the 1830s, German immigrants navigated anti-immigrant sentiment directed towards them. Not until after the Civil War did the German New Orleanians��� social status begin to shift within the southern socio-racial hierarchy. This thesis will demonstrate that German New Orleanians benefitted directly from the expansion of the definition of whiteness in the late nineteenth century as they participated in the racialization of the city���s Italian community. Sources for this study came largely from the city���s local English-language and German-language presses
Improving the Sensitivity of the Search for New Resonances in the X->HH->bbWW Channel at the LHC with the CMS Detector
No full textThe Standard Model (SM) of particle physics successfully describes fundamental particles and three out of four fundamental interactions. However, it fails to incorporate the fourth fundamental interaction, gravity, and cannot explain observed phenomena like matter-antimatter asymmetry. These limitations suggest new physics beyond the SM, possibly probed via Higgs boson pair (HH) production at the CERN Large Hadron Collider (LHC). This dissertation presents the results of a search for new heavy resonances (denoted as ���X���) with spin-0 and spin-2 decaying into HH at the LHC in the bbW+W��� channel, specifically: X ��� HH ��� bbW+W��� ��� bbl+��l�����. It uses 137.6 fb���1 proton���proton collision data at a center-of-mass energy of 13 TeV recorded by the Compact Muon Solenoid (CMS) detector from 2016 to 2018. The presence of two escaping neutrinos in the final state leads to an unconstrained kinematic system, making direct reconstruction of the heavy resonance mass impossible. To address this challenge, the search employs a new technique, called the Heavy Mass Estimator (HME), which estimates the heavy resonance mass in a probabilistic approach. Additionally, compared to an earlier CMS search using only 2016 data, this search extends event selection criteria to enhance signal acceptance and adopts an advanced machine learning architecture. These two enhancements alongside the HME technique significantly increase sensitivity, achieving 2 to 5 times greater sensitivity compared to the 2016 search, assuming the same amount of data. No statistically significant evidence for new heavy resonances is found within the data. Upper limits at a 95% confidence level are set on the production cross sections of new resonances decaying into HH. These limits vary from 7.149 pb to 0.030 pb for spin-0 resonances and from 5.569 pb to 0.023 pb for spin-2 resonances, in the mass range from 250 GeV to 900 GeV
Exploration of New Passive and Active Attacks and Defense Methods for the KLJN and the VMG-KLJN Secure Key Exchangers
No full textThe Kirchhoff-Law-Johnson-Noise (KLJN) scheme is an unconditionally secure (information-theoretic) key exchanger based on the laws of classical statistical physics. The unconditional security of the KLJN scheme is provided by the Second Law of Thermodynamics, which requires thermal equilibrium (homogeneous temperature) for the system with zero flow. The KLJN scheme's foundational security principle was challenged by Vadai, Mingesz, and Gingl (VMG) through their VMG-KLJN system, which operates under inhomogeneous temperature and nonzero power flow conditions, while claiming equivalent security. Through our research, by applying various passive and active attacks against both schemes, we prove ideal KLJN scheme offers superior security over the VMG-KLJN scheme and reaffirm that thermal equilibrium remains the foundation of security. However, the VMG-KLJN method can, with appropriate countermeasures, be sufficiently secure for practical situations.
Our first study reveals that under practical conditions with nonzero cable capacitance and inductance, the VMG-KLJN scheme is vulnerable to certain passive attacks (crossover frequency attack and noise temperature attack), while the original KLJN scheme remains resistant against such attacks. In other words, the VMG-KLJN system is less secure than the original KLJN system. We also show that some of these vulnerabilities can be fixed by yet another new protocol that we introduce here. However at least one of these vulnerabilities will always remain. Thus, the information leak is never mathematically zero.
In our second study, the vulnerability of the VMG-KLJN key exchanger against two active attacks (current injection and voltage insertion attacks) is exposed. The security vulnerability arises from the fact that the effective driving impedances are different between the HL and LH cases for the VMG-KLJN scheme, whereas for the ideal KLJN scheme, they are the same. Two defense schemes are demonstrated, each effective against only one type of attack, but not against the two attacks simultaneously. The theoretical results are confirmed by computer simulations.
In the latter part of the dissertation, we demonstrate the security vulnerability of the ideal KLJN key exchanger and the VMG-KLJN key exchanger, respectively, against transient attacks. Transients start when Alice and Bob (two communicating parties) connect the wire to their chosen resistor at the beginning of each clock cycle. A transient attack occurs during a short duration of time, before the transients reflected from the ends of Alice and Bob mix together. The information leak arises from the fact that Eve (eavesdropper) monitors the cable and analyzes the transients during this time period. We demonstrate such a transient attack, and, then we introduce a defense protocol to protect against the attack. Computer simulations demonstrate that after applying the defense method the information leak becomes negligible
Astrocytic Nik Regulates Local and Systemic Inflammatory and Metabolic Responses
No full textThough NF-��B-inducing kinase (NIK) has well-established roles in inflammatory, immune, and
metabolic regulation on a systemic level, its specific roles in the central nervous system (CNS)
are not well-defined. NIK���s tumor-intrinsic roles in glioblastoma multiforme (GBM) promoting
tumor invasion and growth suggest it could be involved in other neuroinflammatory conditions,
such as stroke and traumatic brain injury, as well as maintain tumor-extrinsic functions in GBM.
Critical in each of these conditions are astrocytes, glial cells of the CNS with diverse immune
and metabolic functions. No study has characterized the function of NIK in astrocytes. Thus, this
thesis aims to examine NIK���s roles in inflammation, immunity, and metabolism within 1) the
CNS overall and 2) specifically through astrocytes ��� critical CNS support cells.
The impact of NIK on GBM survival was investigated via orthotopic implantation of the
syngeneic GL261 GBM model in a total NIK knockout (KO) mouse model. The function of NIK
in astrocytes under basal and lipopolysaccharide-induced inflammatory conditions was explored
with a GFAP-Cre NIK KO mouse model. Output from metabolic cages, transcriptional
regulation of cytokines and metabolic markers in harvested liver and brain tissue, and protein
expression of cytokines in tissue and serum was analyzed in GFAP-Cre NIK KO and control
mice.
Loss of NIK in the GBM tumor microenvironment (TME) increased male mouse survival. With loss of NIK in astrocytes, increased signaling and decreased metabolism was noted both locally and systemically, specific to male mice. After induction of inflammation with LPS, increased astrocytic response and cytokine signaling was identified locally, and decreased tissue inflammation and metabolism systemically, again in male mice.
NIK plays a critical, pro-tumor role within the GBM TME, resulting in increased survival when knocked out. With loss of NIK in astrocytes, systemic homeostasis is impacted, specifically in signaling and metabolic regulation. These effects are significantly more pronounced in males, suggesting a critical sex-specific role of NIK in the CNS and in inflammatory CNS pathologies such as GBM
Characteristics of Atomic Mirrors in Waveguide QED
No full textThis thesis presents a detailed study of photon-atom interactions in one-dimensional waveguide systems, exploring the dynamics of photon decay in atomic cavities and the emission characteristics of single photons from two-level emitters. The study focuses on the decay dynamics of single-photon pulses in cavities formed by atomic mirrors coupled to waveguides and reveals strategies to increase photon storage times by optimizing system parameters such as coupling strength, cavity length, and atomic separation. In addition, the emission of single photons from two-level emitters in atomic cavities is investigated, demonstrating the potential for frequency combing and spectral narrowing through appropriate control of atomic separations. The results of this work contribute to the understanding of light-matter interactions in waveguide quantum electrodynamics and provide insight into the design of novel photonic devices for quantum information processing and communication
Advancements in Cattle Nutrition and Health: From Antimicrobial Strategies to Environmental Sustainability and Innovative Pedagogy
No full textThree experiments were conducted to evaluate 1) the interrelationship between virginiamycin (VM) inclusion, ruminal pH dynamics, and hepatic blood metabolites to determine optimal supplementation phases; 2) the additive effects of condensed tannins (CT) and active dry yeast (ADY) on digestibility and fermentation dynamics; and 3) writing and visual models as a pedagogical strategy for creating individual learning paths in animal nutrition. In the first study, 120 growing steers (304 �� 27 kg) were fed for 150 d to evaluate the strategic administration of VM at 240 mg/d. We concluded that VM supplementation during the whole feeding phase tended to decrease the time spent under pH 5.8 (P = 0.081), thus improving rumen buffering capacity and reducing acidotic events. Additionally, VM inclusion lessened the acute phase protein response during the transition between the grower and finisher diet. In the second study, 23 ruminally cannulated steers (284.3 �� 4.1 kg) were utilized in a factorial design to evaluate the supplementation of ADY at 10 g/d, CT at 1 % DM of quebracho extract (0.78% total CT and 0.312% PPP on DM basis), and combined CT and ADY (CTY; 1% DM and 10 g/d, respectively). In vitro methane production was affected in a quadratic fashion (P = 0.001) as days progressed, with CTY being less relative to CON, CT and ADY (8.14 vs. 14.69 mM, respectively). The inclusion of ADY and CT did not affect ruminal variables (total VFA, protozoa, pH and redox; P ��� 0.05). However, apparent total tract DM digestibility (aDMD) and neutral detergent fiber digestibility (aNDFD) for CTY (60.08% and 51.78%, respectively) were intermediate of ADY and CT supplementation, aligning with our intended outcome of combining them. In the third study, students (n = 27) who participated in the honors contract of an upper-level animal nutrition course were asked to participate in a self-directed learning project. Likert scale surveys (88.8% response rate) and reflections reported that writing to learn gave them an authentic scientific writing experience that when paired with the creation of visual models improved their confidence and ability to interpret and integrate concepts from lecture and outside sources
Three Essays on the Economics of Resource Conservation in Agriculture
No full textThis dissertation presents three essays that explore the economics of water and soil conservation in agriculture. The overarching focus of this work is on the impact and cost of conservation programs and policies aimed at conserving natural resources, as well as studying potential barriers to their implementation.
The first essay is an empirical study assessing the cost of reducing water use from irrigated agriculture in the Colorado River Basin. Utilizing basin-wide farm-level data into an econometric choice modeling framework, I simulate farmers��� crop choices under different hypothetical conservation prices paid for per acre-foot of water. I use the predicted crop shares to derive the abatement cost curve of water, which estimates the cost of an additional unit of water conserved in agriculture. My findings suggest that water abatement appears negligible at prices below $200 per acre-foot, but increases thereafter with a significant regional heterogeneity in the marginal cost of additional conserved water. Specifically, my results suggest that marginal abatement cost is smaller in the Lower Basin states of the river, suggesting opportunities for higher levels of conservation at relatively lower costs in this region.
The second essay studies the direct and spillover effect of an extension-based contest program in Arkansas, designed to promote the adoption of irrigation best management practices among pro-ducers. Specifically, I study how participation in the ���Most Crop per Drop��� irrigation yield contest, which ranks participants by water use efficiency and provides feedback on their performance, influences their adoption of irrigation practices. Results show that participation in the contest is positively correlated with a four percent increase in the average adoption of irrigation practices. Additionally, there appears to be an indirect positive spillover effect from the contest, which has influenced the behavior of those producers who were not participants of the program but were indirectly linked to it.
In the third essay, I investigate the difference in the adoption of conservation practices among different groups of producers based on their tenure status. I use operation-level data from the Census of Agriculture for all 48 contiguous states to test whether the enrollment in land retirement programs, and the use of on-farm conservation practices differ among full-owner, part-owner, and full-tenant operations. My results suggest that part-owners and full-tenants are more likely than full-owners to adopt practices such as reduced-tillage and using cover crops. Based on my findings, full-owners are using no-till practice at higher rates than other tenure categories, and are also enrolling higher shares of their operation into land retirement programs
Functional Analyses of TMTC-Type O-Mannosyltransferases in Drosophila
No full textOxygen-linked mannosylation, also known as Protein O-mannosylation, is a type of glycosylation, obstruction of which has been shown to cause severe phenotypes in humans, from neurological abnormalities to congenital muscular dystrophies. O-mannose modifications are of special interest due to their essential role in nervous system development. Protein O-mannosyltransferases (POM) are the enzymes responsible for O-mannosylation. They are highly conserved in metazoans. A majority of human O-mannosyltransferase enzymes have homologs present in Drosophila, including canonical protein O-mannosyltransferases, POMT1 and 2, (designated as Rt and Tw in Drosophila), and recently discovered non-canonical O-mannosyltransferases, transmembrane O-mannosyltransferases targeting cadherins 1-4 (TMTC1- TMTC4), all of which share conserved sequence, and structure with their human counterparts. TMTCs have been shown to selectively modify cadherins and protocadherins in humans. Yet the functions of the O-mannose modifications from individual TMTCs in humans and Drosophila are not well understood. In order to address this, we focus on elucidating the molecular mechanisms and functions of O-mannosylation mediated by TMTC1 & 2 in Drosophila. Using the advantages of the Drosophila model, I investigate the effect of TMTC-mediated modifications on the development of the nervous system, behavior, and neurological functions. In my project, I focus on a deeper understanding of how O-mannose modifications affect cadherin function at the molecular, cellular, and organismal levels. Investigating the localization, expression levels, and functional effects of TMTC targets in TMTC mutants will shed light on the function of O-mannose. I analyzed mutant alleles of TMTC1 and TMTC2 and employed rescue constructs to restore functions using both Drosophila and human constructs. I investigated possible redundancy and collaboration within the TMTC gene family by combining the downregulation of different TMTCs and using various transgenic approaches. My results revealed that TMTC1 & TMTC2 function in a partially redundant manner to establish sensory axon connections in the larval brain. My results shed light on the in vivo functions of TMTCs, their role in the regulation of cadherin functions, and have built a Drosophila model for further elucidation of the mechanism of thus highly conserved non-canonical O-mannosylation pathway in animals, including the role of TMTC genes in human biology and pathological conditions
Diasporic Imprint on Religious Architecture: Post-1965 South Asian Mosques in Houston
No full textDiaspora plays a role in shaping and reimagining the built environment that ethnic groups establish in a foreign land. Mosques, both as individual buildings and as a part of Islamic centers, function as the space for congregational prayer for Muslim worshippers. Mosques serve as a way for Muslims to express cultural values and identity. When placed in a diasporic environment, mosques combine inherited traditions with the diasporic needs of immigrant Muslims. The objective of this research is to investigate and understand how South Asian immigrants have developed the architecture of mosques and Islamic centers in the Greater Houston Area since the 1965 Hart-Cellar Act was passed, and how they have merged diasporic and traditional design elements in mosque architecture. The research hypothesizes that the architecture of South Asian American mosques in Greater Houston is an attempt to retain cultural identity through the hybridization of traditional and diasporic influences.
An explanatory research method has been implemented to do a comparative case study analysis of three cases of mosques and Islamic centers located in Greater Houston. Data for the research has been collected through literature review, archival studies, and field observation. The thesis is expected to provide a cultural narrative on the development of South Asian American mosque architecture within the diaspora of Greater Houston and add to the existing history of South Asian American religious architecture