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The Classical-Nonclassical Polarity of Gaussian States
No full textGaussian states with nonclassical properties such as squeezing and entanglement serve as crucial resources for quantum information processing. Accurately quantifying these properties within multi-mode Gaussian states has posed some challenges. In this work, we first give a detailed review to Gaussian state. To address these challenges, we introduce a unified quantification: the ���classical-nonclassical polarity���, represented by P. For a single mode, a positive value of P captures the reduced minimum quadrature uncertainty below the vacuum noise, while a negative value represents an enlarged uncertainty due to classical mixtures. For multi-mode systems, a positive P indicates bipartite quantum entanglement. We show that the sum of the total classical-nonclassical polarity is conserved under arbitrary linear optical transformations for any two-mode and three-mode Gaussian states. For any pure multi-mode Gaussian state, the total classical-nonclassical polarity equals the sum of the mean photon number from single-mode squeezing and two-mode squeezing. Our results provide a new perspective on the quantitative relation between single-mode nonclassicality and entanglement, which may find applications in a unified resource theory of nonclassical features
Biological Roles of Bone Morphogenetic Protein 1 (BMP1) in Periodontium
No full textThis thesis explores the pivotal role of Bone Morphogenetic Protein 1 (BMP1) in the development and maintenance of the periodontium, employing Bmp1 conditional knockout (cKO) mouse models. The research involved creating a unique lineage of mice with a targeted deletion of the Bmp1 gene in dental follicle cells during early embryonic development, specifically in the progenitor cells destined to differentiate into alveolar bone osteoblasts, cementoblasts, and periodontal ligament (PDL) fibroblasts, known as Osr2-Cre;Bmp1^flox/flox mice. This study provides a detailed comparative analysis of the alveolar bone, cementum, and PDL structures in these Bmp1 cKO mice against normal control mice through various analytical methods, including plain x-ray radiography, histological examination, and immunohistochemical (IHC) analysis. Our findings reveal significant disruptions in PDL collagen fiber organization and bone matrix development, leading to substantial alveolar bone loss in Bmp1 cKO mice at both 6 and 24 weeks of age. Histological and IHC analyses highlighted a reduction in PDL integrity, abnormal protein distributions, and significant decreases in Dentin Matrix Protein 1 (DMP1) levels, suggesting BMP1's essential role in collagen synthesis and the overall mineralization process. Notably, irregular distribution patterns of periostin and fibrillin, underscore the profound impact of BMP1 deletion on dental morphology and periodontal health. The study conclusively demonstrates that BMP1 is critical for the structural integrity and functional maintenance of the periodontium, influencing various proteins involved in the development and health of the periodontal ligament and alveolar bone. The observed defects in Bmp1 cKO mice highlight the importance of BMP1 in collagen network maintenance and alveolar bone formation, with significant implications for periodontal disease pathology and treatment strategies. This research underlines the complex interplay between BMP1 and other proteins in periodontal development, providing invaluable insights into the mechanisms underpinning periodontal health and disease
The Design of a Mobile E-Beam Treatment Station for Contaminated Soils
No full textThe presence of perfluorooctanoic substances (PFAS), a manufactured chemical used in various applications, has raised concerns due to its widespread impact on the environment and hazardous effects on human health. Energetic destructive methods such as thermal, supercritical oxidation, and the electron beam (eBeam) are currently being investigated as possible methods to mitigate this issue. These technologies are more efficient at separating contamination from its media and do not produce a contaminated byproduct. However, these technologies have yet to be proven at a scale at which it can be used to combat this contamination effectively.
This thesis investigates two different design configurations as a scaled pilot for mobile e-beam soil treatment systems by addressing structural and spatial concerns. Structural concerns were addressed by analysis completed in SolidWorks finite element analysis features. The two designs are then compared by considering factors such as radiation shielding, manufacturability, size and throughput, mobility, cost, and ease of setup. PUFFIn+ is used to simulate various electron beam soil interaction parameters such as beam energy, soil thickness and beam utilization efficiency.
These considerations and comparisons result in a final mobile electron beam facility recommendation of the following; the design should be able to be transported using only one trailer, the trailer chassis will require three or more axles and will be an oversize load, the power of the beam should be 3 MeV 50 kW, the optimal thickness of media at this beam energy is 0.5cm, the thickness of shielding if stainless steel is used should be approximately 6 inches around the treatment room, a clamshell shielding should be put around the accelerator, and all conveyors regarding media processing should be metal alloys to avoid contamination. More specific design recommendations are discussed in further detail in the text
Multi-Cycle Dynamic Compaction of At-Speed Tests for Reduction in Test Data Volume, Test Application Time, and Power Supply Noise
No full textThe semiconductor industry has made great strides over the last few decades. Chip makers taking advantage of Moore���s law have pushed the limits of physics to shrink feature sizes on Silicon (Si) wafers. Delay test is an essential structural manufacturing test used to determine the maximal frequency at which the chip can run without incurring any functional failures. Small delay defects that were previously benign now manifest as delay faults due to the reduced timing margins. Another challenge is achieving better delay correlation with functional test, which is dominated by power supply noise (PSN). Differences in PSN between functional and structural tests can lead to differences in chip operating frequencies of 30% or more. Pseudo functional test (PFT), based on a multicycle clocking scheme, has better PSN correlation with functional test compared with traditional two-cycle at-speed test. This research focuses on the development of new test. methods for small delay defects, within the limits of affordable test generation cost, pattern count and power supply noise.
First, this work proposes a new Dynamic Compaction algorithm to generate compacted test sets for K Longest paths per gate (KLPG) in scan based sequential circuits. The algorithm uses a greedy approach to compact paths with non-conflicting assignments together over multiple at-speed cycles during test generation. Reductions in pattern counts of as much as 67% are observed with the greedy approach.
Second, compression is introduced to the test flow and the ATPG engine to observe the combined effect of compression and compaction. Multi-cycle at-speed test has around 60% reduction in pattern count over single-cycle at-speed test with similar compression rates. Higher compression rates are required for single cycle test to achieve similar test data volume and test application time which indicates more DFT effort required for single cycle at-speed tests. The compression framework is built inside the CodGen ATPG to make this process more seamless.
Third, a simulation-based test relaxation algorithm is designed for CodGen ATPG as the patterns generated by the final justification SAT Engine assigns all the bits in the pattern. This algorithm implemented inside CodSim is able to produce similar don���t care bit density compared to the previous justification algorithms inside CodGen such as FAN and PODEM. Power supply noise (PSN) estimation using weighted switching activity (WSA) is then done for these partially specified patterns (with random or adjacent fill) to compare the single and multi-cycle test power. The multi-cycle test has very similar power profile and even lower in some cases to that of single-cycle test even though the patterns are more compacted.
Finally, CodGen ATPG is improved to handle larger industrial designs by updating the SAT engine MiniSat that runs all binary justifications during the ATPG process. It is replaced with CaDiCaL a much modern SAT engine which has been able to provide significant speedup to the test generation process
Selective Aryl Hydrocarbon Receptor Modulators as a Potential Treatment for Major Depressive Disorder
No full textMajor depressive disorder (MDD) is a worldwide public health concern, and although treatments exist, many people still suffer from treatment resistant depression. The projects in this dissertation aimed to evaluate the feasibility of using selective aryl hydrocarbon modulators (SAhRMs) as a treatment for MDD. The aryl hydrocarbon receptor (AhR) is a ligand-activated intracellular transcription factor that is involved in numerous biological processes which are linked to potential causes of MDD. Two SAhRMs, 3,3���-diindolylmethane (DIM) and 1,4-dihydroxy-2-napthoic acid (DHNA) were tested for their ability to prevent and treat MDD-like behavior in female mice using unpredictable chronic mild stress (UCMS). Depression- and anxiety-like behaviors were examined using a battery of behavioral tests. In the first project, both SAhRMs prevented and reversed depression-like behavior but had little effect on anxiety like behavior. An isomer of DHNA, which is inactive at the AhR, did not prevent depression-like behavior, hinting at a role for AhR activity in the antidepressant action of DHNA. In the second project, male mice were examined, and SAhRMs did not act as antidepressants but had some effects on anxiety-like behavior in males. There was no effect of SAhRMs on spatial learning or on weight gain in stressed or unstressed male or female mice. The third project tested mice which do not express the AhR in the internal epithelium (AhR��IEC). AhR��IEC mice were resilient to the effects of stress on depression-like behavior, suggesting a role for intestinal AhR in maintaining depression- like states. Additionally, SAhRMs prevented depression-like behavior in these mice, effectively eliminating the intestinal epithelium as a potential site of action for SAhRMs. Limitations, possible mechanisms, and applications are discussed. The results of these studies indicate a potential for SAhRMs to be developed as a treatment for MDD and highlight the need to further investigate the role of AhR in MDD
Addressing the Escalating Impact of Rice Kernel Smut: Insights into Genetic Diversity, Fungicide Resistance, Seed Endophytes, and Cultivar Resistance for Effective Management
No full textOnce considered a minor disease, rice kernel smut, caused by Tilletia horrida, has become one of the most economically important rice diseases in the US. With a lack of resistant rice cultivars, management heavily relies on the midseason preventive applications of propiconazole-based fungicides. However, the effectiveness of fungicide application seldom effective due to gaps in knowledge of the disease���s biology and epidemiology. We address, for the first time, the genetic diversity, fungicide resistance, seed endophytic microbiome, and host resistance, with the target to develop an effective kernel smut management program. We performed multi-locus sequence analysis to explore the genetic diversity of 63 T. horrida isolates collected from across the US. These isolates were grouped into five clades, with 59% of the isolates clustering together. The ITS region phylogeny grouped the 22 Tilletia spp. from eight different countries (Australia, China, India, Korea, Pakistan, Taiwan, The US, and Vietnam) together. Of the 63 US T. horrida isolates tested here, >80% were found to be tolerant at the baseline propiconazole concentration of 0.2 mg/L. While over 60% of the isolates displayed no inhibition at a concentration of 10 mg/L, 22% of the isolates tolerated at 25 mg/L, and one single isolate was not inhibited even at 50 mg/L. The T. horrida genomes sequenced, assembled, and annotated as part of this thesis revealed the presence of a single copy of Cyp51, a target gene for demethylation inhibitors (DMIs). In the cyp51 protein sequences of propiconazole-resistant isolates, five amino acid substitutions, G22A, R183K, V279A, L387I, and G494S, were observed. An efficient artificial inoculation method was established for T. horrida infection. Direct injection with pathogen spores onto developing panicles at the late-boot stage resulted in a higher level of disease infection compared to other inoculation methods evaluated. Field evaluation of 32 rice cultivars identified nine cultivars with partial resistance to kernel smut. An amplicon-based analyses of seed endophytic microbial diversity revealed differences between organic and conventional rice farming systems, with higher bacterial diversity in the latter and increased fungal diversity in the former. In parallel the cultivable endophytic bacteria isolated from rice seeds were identified based on the full-length 16S rRNA gene sequences. Among the 31 unique bacterial isolates tested in vitro, the strains Bacillus sp. ST24, Burkholderia sp. OR5, Pantoea sp. ST25, and Pseudomonas sp. OR4 exhibited antagonistic activities against T. horrida and, three seedling blight pathogens (Marasmius graminum, Rhizoctonia solani AG4, and R. solani AG11). The findings of this study provide insights into genetic diversity, fungicide resistance, and seed endophytes, and cultivar resistance for effective management of kernel smut in rice
Probing Membrane Protein-Ligand Interactions Using Native Mass Spectrometry
No full textThe cell membrane, essential for cellular structure and function, is composed largely of membrane proteins and lipids. While transmembrane proteins are known for their critical roles in various physiological processes such as maintaining cell resting potential and facilitating molecule transport, the specific interactions between these proteins and different lipid moieties are not fully understood. In this study, we employed native mass spectrometry as a primary tool to unravel these interactions, capitalizing on its unique ability to preserve non-covalent interactions in biomacromolecules.
Our investigation comprised two distinct approaches: single ligand screening and multi-omic screening. Through single ligand screening, we identified specific lipid moieties that bind to the mammalian two-pore domain potassium channel TRAAK. This approach not only pinpointed the preferred lipids but also revealed a dose-response relationship with TRAAK potassium efflux in functional assays. On the other hand, our multi-omic analysis yielded significant findings. It corroborated the unique allosteric modulation observed between cardiolipin and phosphatidylethanolamine in their interaction with the E. coli ammonium channel AmtB, aligning with previous research. Additionally, this approach led to the discovery of a complex allosteric modulation involving TRAAK, phosphatidylserine, and cupric ions. Impressively, these interactions were maintained when ejected from proteoliposomes, bridging our functional assays, and validating our methodologies.
Moreover, our research broke new ground with the synthesis of novel charge-reducing molecules. This advancement has significantly enhanced the study of less stable membrane proteins, paving the way for more comprehensive exploration of membrane protein-lipid interactions. Overall, our findings contribute substantially to the understanding of cellular membrane dynamics and functionality, marking a significant stride in the field of cellular biology
The How and Why of Realness: Reconceptualizing Identity Management and Examining Relationships with Authenticity and Motivation in a U.S.-Based LGBTQ2+ Sample
No full textIn this dissertation I examined whether the relationship between the identity management behaviors of LGBTQ+ employees and workplace outcomes (work engagement and affective well-being) is mediated by authenticity. Furthermore, I considered whether autonomous and controlled motivations for identity management behaviors moderate this relationship. In doing so, I add to identity management research that presumes but rarely tests the mediating effects of authenticity and I question the presumption that LGBTQ+ employees are always motivated to share their identities for autonomous reasons and hide them for controlled reasons. Additionally, I explored an alternative approach to measuring identity management behaviors, dividing them into verbal and nonverbal behaviors. Using a correlational design, I collected survey-based quantitative data from 456 LGBTQ+ identifying workers through the online data collection platform Prolific during the months of October and November 2023. Analyses conducted using the PROCESS macros indicated that the relationship between closed communication (e.g., verbal concealment and nonverbal suppression) and outcomes was mediated by authenticity, but this was not the case for open communication (e.g., verbal disclosure and nonverbal expression). There was an interaction effect between autonomous motivation and identity communication behaviors, such that for individuals with lower levels of autonomy, engaging in more open communication behaviors and/or more closed communication behaviors predicted diminished feelings of authenticity as well as reduced outcomes. Based on exploratory path analyses, the division of open communication into verbal and nonverbal behaviors better represented the true population model than combining these behaviors into one variable, however, there was no difference in model fit when closed communication was divided into verbal and nonverbal behaviors compared to a single-variable measure. I conclude by discussing theoretical and practical implications of these findings and propose future directions for this research
Innovative Fabrication of Asymmetric Mixed-Matrix Membranes for Gas Separation
No full textDespite extensive research on mixed-matrix membranes (MMMs), their path to commercial deployment has been obstructed by a range of scientific and engineering barriers. This study introduces a novel, one-step method for fabricating MMMs, promising to advance their commercialization by addressing many of these existing challenges. This method, known as phase-inversion in sync with metal-organic framework (MOF) formation (PIMOF), allows for the swift creation of high-performance, asymmetric MMMs on a scalable basis. It involves a polymer film undergoing phase inversion while ZIF-8 nanoparticles are simultaneously generated in-situ within the polymer matrix. The produced MMMs exhibit exceptional propylene/propane separation efficiency, largely owing to the high effective ZIF-8 loading and the augmented molecular sieving capability of the uniquely small sub-5 nm ZIF-8 filler nanoparticles, facilitated by restricted linker swing motion. Subsequently, our research delves into the impact of modulating ligands, sodium formate and 1,4-butanediol, on the development of ZIF-8 fillers within the polymer matrix, aiming to elevate the separation capabilities of asymmetric MMMs crafted via the PIMOF technique. Our computational analysis supplements this empirical research, examining how the size of ZIF-8 nanoparticles influences the specific surface interaction energy and the apertures of ZIF-8. The findings suggest that smaller ZIF-8 nanoparticles foster stronger interactions with the polymer, affecting the nanoparticle's aperture size. These advancements mark a significant leap forward, surpassing the performance of all previously documented propylene-selective MMMs. Lastly, a hybrid strategy that involves the mixing of metals and/or linkers has been explored to precisely adjust the porosity and surface characteristics of the ZIF framework, thereby broadening their utility in the separation of various critical gas mixtures. The technique of linker-doping, as detailed in this report, represents a viable approach to diversify the range of imidazolate linkers, enabling the creation of mixed-linker hybrid ZIFs. Specifically, the doping of 2-ethylimidazole (eIm) into the frameworks of ZIF-8 and ZIF-67 has been examined, demonstrating the potential of this innovative method to improve gas transport across the membranes. This approach not only illustrates the adaptability of ZIF materials to meet diverse separation needs but also highlights the potential for tailored membrane design to enhance separation performance
Megahertz Rate Spectroscopic Investigation of Hypervelocity Impact Flash
No full textUnderstanding hypervelocity impacts (HVI) has become crucial to several fields, such as space exploration, planetary science, aerospace engineering, and defense-related applications. HVIs are highly dynamic and extreme phenomena characterized by the immense and rapid transfer of energy between colliding bodies. One manifestation of this transformation of kinetic energy during and immediately following an HVI is the emission of an intense flash of light. Researchers investigating these optical emissions emanating from HVIs refer to this phenomenon as the ���impact flash.��� The impact flash can be noticed across a wide range of impact scenarios: both high and low impact velocities; in the vacuum of outer space, as well as the atmosphere of the earth; with both solid and liquid objects; and across metallic, ceramic, and polymer materials. Investigations into the impact flash have sought to establish connections between impact conditions, temporal evolution of different spectroscopic features, and underlying material failure mechanisms. Characterization of this phenomenon can also act as an indicator for a spatial and temporal evolution of material damage. Typical studies of the impact flash make use of a diverse array of optical diagnostics tools and methods. These include high-speed cameras, photodiodes and photomultiplier tubes, pyrometers, laser interferometers, and spectrometers. Stop-motion or relatively low-rate spectral analysis systems have been employed to measure HVI-induced light emission, providing some spectral information related to the dynamic material behavior and projectile-to-target energy transfer. The relatively short time scales (microseconds) and rapidly evolving impacted material response characteristics of HVI events necessitate the use of highspeed detectors with superior temporal resolution to capture the impact flash evolution with sufficient temporal resolution.
Hence, the objective of this thesis research is to develop two high-speed transient spectral analysis systems for investigating the evolution of the impact flash. The first system, an ultrahigh-speed spectrometer (UHSS), has been developed to capture and analyze the transient light emission induced by HVIs in a two-stage light gas gun (2SLGG) facility, with sub-microsecond (i.e., megahertz-rate) temporal resolution. The UHSS makes use of a MHz-rate complementary metal��� oxide���semiconductor (CMOS) camera coupled to an imaging spectrometer, resulting in MHz-rate spectral imaging characterization. This system was used to record time-resolved spectral images of HVIs at speeds up to 6 km/s from spherical aluminum projectiles impacting both aluminum and stainless-steel targets. The high-speed spectral images recorded allowed us to compare the evolutionary behavior of energized metallic species and combustion byproducts in the nano- and microsecond time scales following the impacts. This study found that even at similar impact conditions, the light emission behavior of aluminum-on-aluminum and aluminum-on-stainless-steel impacts can be substantially different. Aluminum target impacts showed one temporal peak in light intensity, whereas the stainless-steel targets showed an additional secondary peak of emitted light. Additionally, in stainless-steel impacts, combustion byproducts were seen to feature a stronger second peak than pure metallic species.
The second high-speed spectral analysis system, a fiber-based multi-spectral diagnostics (FMSD) system, makes use of a fiber bundle to direct light from the impact flash into a collection of highspeed silicon photodiodes. A gigahertz-rate oscilloscope receives the output voltage from these photodiodes as light reaches each photodiode. By placing unique spectral filters in front of each photodiode, these photodiodes are used to capture signals from a specific species. The design of the FMSD was validated using laser-induced plasma experiments. Engineering improvements and subsequent implementation in future HVI studies are discussed