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Full-Text Articles in Physical Sciences and Mathematics

Narrative Engineering: Tools, Computational Structure, And Impact Of Stories, Michael A. Debuse Dec 2024

Narrative Engineering: Tools, Computational Structure, And Impact Of Stories, Michael A. Debuse

Theses and Dissertations

Computational Linguistics has a long history of applying mathematics to the grammatical and syntactic structure of language; however, applying math to the more complex aspects of language, such as narrative, plot, scenes, character relations, causation, etc. remains a difficult topic. The goal of my research is to bridge the narrative humanities with mathematics, to computationally grasp at these difficult topic, and help develop the field of Narrative Engineering. I view narrative and story with the same mathematical scrutiny as other engineering fields, to take the creativity and fluidity of story and encode it in mathematical representations that have meaning beyond …

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Coding For Decentralized Systems And Forensic 3d Fingerprinting, Canran Wang Dec 2024

Coding For Decentralized Systems And Forensic 3d Fingerprinting, Canran Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

This dissertation presents novel coding techniques that optimize communication costs and address security challenges in decentralized systems and 3D printing technologies. The first part focuses on encoding data in distributed systems in a decentralized manner, i.e., without a central processor which orchestrates the operation. In such systems, processors require coded data generated from inputs provided by source processors. An example is a distributed storage system with geographically dispersed nodes storing a large database collected by specific source processors. To reduce communication costs, we propose a universal solution applicable to any linear code, with optimizations for systematic Reed-Solomon and Lagrange codes, …

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Reconstructing Superoscillations Buried Deeply In Noise, Derek D. White, Shunxing Zhang, Barbara Šoda, Achim Kempf, Daniele C. Struppa, Andrew N. Jordan, John C. Howell Dec 2024

Reconstructing Superoscillations Buried Deeply In Noise, Derek D. White, Shunxing Zhang, Barbara Šoda, Achim Kempf, Daniele C. Struppa, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We utilize a method using frequency combs to construct waves that feature superoscillations—local regions of the wave that exhibit a change in phase that the bandlimits of the wave should not otherwise allow. This method has been shown to create superoscillating regions that mimic any analytic function—even ones well outside the bandlimits—to an arbitrary degree of accuracy. We experimentally demonstrate that these waves are extremely robust against noise, allowing for accurate reconstruction of a superoscillating target function thoroughly buried in noise. We additionally show that such a construction can be easily used to range-resolve a signal well below the commonly …

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Butte Priority Soils Operable Unit (Bpsou) Final Bpsou Insufficiently Reclaimed Sites Belle Of Butte (Bres No. 8 & Ur-39) Remedial Action Work Plan (Rawp) Request For Change Ir- 2024-Ra-02, Mike Mcanulty Dec 2024

Butte Priority Soils Operable Unit (Bpsou) Final Bpsou Insufficiently Reclaimed Sites Belle Of Butte (Bres No. 8 & Ur-39) Remedial Action Work Plan (Rawp) Request For Change Ir- 2024-Ra-02, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Butte Priority Soils Operable Unit (Bpsou) Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoon System – Third Quarter 2024., Dave Griffis Dec 2024

Butte Priority Soils Operable Unit (Bpsou) Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoon System – Third Quarter 2024., Dave Griffis

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Transparency And Authority Concerns With Using Ai To Make Ethical Recommendations In Clinical Settings, Jeffrey Byrnes, Michael Robinson Dec 2024

Transparency And Authority Concerns With Using Ai To Make Ethical Recommendations In Clinical Settings, Jeffrey Byrnes, Michael Robinson

Philosophy Faculty Articles and Research

In response to recent proposals to utilize artificial intelligence (AI) to automate ethics consultations in healthcare, we raise two main problems for the prospect of having healthcare professionals rely on AI-driven programs to provide ethical guidance in clinical matters. The first cause for concern is that, because these programs would effectively function like black boxes, this approach seems to preclude the kind of transparency that would allow clinical staff to explain and justify treatment decisions to patients, fellow caregivers, and those tasked with providing oversight. The other main problem is that the kind of authority that would need to be …

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Ethical Aspects Of Utilising Artificial Intelligence In Clinical Settings, Jeffrey Byrnes, Michael Robinson Dec 2024

Ethical Aspects Of Utilising Artificial Intelligence In Clinical Settings, Jeffrey Byrnes, Michael Robinson

Philosophy Faculty Articles and Research

In response to recent proposals to utilize artificial intelligence (AI) to automate ethics consultations in healthcare, we raise two main problems for the prospect of having healthcare professionals rely on AI-driven programs to provide ethical guidance in clinical matters. The first cause for concern is that, because these programs would effectively function like black boxes, this approach seems to preclude the kind of transparency that would allow clinical staff to explain and justify treatment decisions to patients, fellow caregivers, and those tasked with providing oversight. The other main problem is that the kind of authority that would need to be …

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Finite-Difference Time-Domain Simulation For Interpreting Regional Infrasound Arrivals And Estimating Propagation Path Effects, Jesse Howard Dec 2024

Finite-Difference Time-Domain Simulation For Interpreting Regional Infrasound Arrivals And Estimating Propagation Path Effects, Jesse Howard

Earth Sciences Theses and Dissertations

New full-wave infrasound simulation tools were developed based on an optimized finite-difference time-domain solution of 2D axisymmetric linear and nonlinear fluid dynamic equations. These tools were applied to estimate propagation path effects and enhance phase interpretation for regional infrasound arrivals. Middle-atmosphere full-wave predictions for a range of idealized atmospheres show that shadow zone arrivals and fast and slow arrival pair components from multiple ducts can be delineated using a combination of full-wave modeling and geometrical acoustics. Relationships between phase velocity and effective sound profile were established for each arrival type. Implications for source characterization were that amplitude and spectrum variation …

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Modeling Of Light Filamentation For Nonlinear Imaging And Waveguiding, Nicholas Bagley Dec 2024

Modeling Of Light Filamentation For Nonlinear Imaging And Waveguiding, Nicholas Bagley

Mathematics Theses and Dissertations

Ultrashort pulses are capable of extremely high powers; in addition to enabling various applications in defense, sensing, and imaging, they provide a useful arena in which to study nonlinear optical phenomena that are observable only at high intensities. Due to these effects, which can include ionization and thermal blooming, simulation of ultrashort pulse propagation is a complicated multiphysics problem. We provide an overview of techniques used to simulate the propagation of ultrashort pulses in the nonlinear regime, including the formation of light filaments due to the competition of Kerr self-focusing and defocusing (e.g. via plasma generation). We discuss both carrier-resolved …

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Measuring And Improving Api Usability And Quality: A Comprehensive Framework And Empirical Study, Sultan Alanazy Dec 2024

Measuring And Improving Api Usability And Quality: A Comprehensive Framework And Empirical Study, Sultan Alanazy

Computer Science and Engineering Theses and Dissertations

Cloud computing provides on-demand access to flexible computing resources, enabling rapid application deployment without substantial infrastructure investment. Application Programming Interfaces (APIs) play an important role in ensuring the success of cloud applications. The primary users of APIs are the extensive community of application programmers who search, read, and understand APIs before integrating them into their applications or systems. In addition, developers often turn to online API support when seeking help. Problems in such support can result in incorrect API usage and integration problems. There is an urgent need to measure API usability and support issues to identify, characterize, and assess …

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Extraordinary 21st Century Drought In The Po River Basin (Italy), Abel Andrés Ramírez Molina, Glenn Tootle, Giuseppe Formetta, Thomas Piechota, Jiaqi Gong Dec 2024

Extraordinary 21st Century Drought In The Po River Basin (Italy), Abel Andrés Ramírez Molina, Glenn Tootle, Giuseppe Formetta, Thomas Piechota, Jiaqi Gong

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Recent research identified 2022 as being the year of lowest seasonal April–May–June–July (AMJJ) observed streamflow for the Po River Basin (PRB) in the past two centuries. Expanding upon this research, we applied filters (2-year to 30-year filters) to the AMJJ observed streamflow and identified the late 20th and 21st century as displaying extreme drought. In this study, we introduce PALEO-RECON, an automated reconstruction tool developed to leverage tree ring-based proxies and streamline regression processes. Using PALEO-RECON, we reconstructed the AMJJ streamflow, applying traditional regression techniques and using a nested approach in which 30-, 40-, and 50-year windows within the ~200-year …

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Summed Series Involving 1F2 Hypergeometric Functions, Jack C. Straton Dec 2024

Summed Series Involving 1F2 Hypergeometric Functions, Jack C. Straton

Physics Faculty Publications and Presentations

Summation of infinite series has played a significant role in a broad range of problems in the physical sciences and is of interest in a purely mathematical context. In a prior paper, we found that the Fourier–Legendre series of a Bessel function of the first kind JN(kx) and modified Bessel functions of the first kind IN(kx) lead to an infinite set of series involving 1F2 hypergeometric functions (extracted therefrom) that could be summed, having values that are inverse powers of the eight primes 1/ ( 2i 3j 5k …

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Parallel Circles: A Math Club As A University Math Circle, Sarah C. Cobb, Marcos Lopez Dec 2024

Parallel Circles: A Math Club As A University Math Circle, Sarah C. Cobb, Marcos Lopez

Journal of Math Circles

This paper will discuss a monthly social event for the University Math Club. Over the past several years, the event has been shaped by the philosophy of a Student Math Circle. We will discuss the event's organization and the ways it has benefited from the influence of the Math Circle community.

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Analysis Of Monthly And Annual Air Temperature Trends In Port-Said City, Egypt, Amna S. Dabbous, Yasser M. El-Wakeel, Tarek M. El-Geziry Dec 2024

Analysis Of Monthly And Annual Air Temperature Trends In Port-Said City, Egypt, Amna S. Dabbous, Yasser M. El-Wakeel, Tarek M. El-Geziry

Blue Economy

This study examined fluctuations in a long-term air temperature record in Port Said to determine the existence or absence of climate change in this significant Egyptian metropolis. The data period runs 31 years, from 1991 to 2021. The study investigated the homogeneity of the annual data and used a linear regression approach to characterize the trend of air temperature variations during the study period. Furthermore, the Mann-Kendall test was used to assess trend significance, as well as anomaly calculations to statistically specify severe air temperature episodes. The results showed that the data were homogeneous. Monthly mean air temperatures increased at …

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Optimization Of The Starch Chitosan-Based Flocculant Crosslinked By Ethylene Glycol Dimethacrylate On Removing Dypro 19 Textile Dye From Wastewater, Asep Nurohmat Majalis, Putri Ramadhani, Hendris Hendarsyah Kurniawan, Axel Dimaz Sanusi Pasaribu, Hafiizh Prasetia, Fitri Yuliani, Andreas Andreas, Hartati Hartati Dec 2024

Optimization Of The Starch Chitosan-Based Flocculant Crosslinked By Ethylene Glycol Dimethacrylate On Removing Dypro 19 Textile Dye From Wastewater, Asep Nurohmat Majalis, Putri Ramadhani, Hendris Hendarsyah Kurniawan, Axel Dimaz Sanusi Pasaribu, Hafiizh Prasetia, Fitri Yuliani, Andreas Andreas, Hartati Hartati

Karbala International Journal of Modern Science

Dyes used in industry, especially textile dyes, are one of the water pollutants that receive much attention because they are potentially toxic, carcinogenic, mutagenic, and generally challenging to decompose naturally. Textile dyes from wastewater can be removed through coagulation-flocculation. However, conventional coagulation-flocculation based on Fe and Al salts and synthetic polymers often leaves residual pollution. In this research, the performance of the new biopolymer-based flocculant, namely starch-ethylene glycol dimetacrylate-chitosan (SEC), which can act as coagulants and flocculants in solid-liquid separation of textile dyes, has been optimized using response surface methodology (RSM) approach. The influences of several independent variables, such …

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Breast Cancer Area Identification In Mammograms Using Expectation Maximization Gaussian Mixture Model, Rizki Khoirun Nisa, Dian Kurniasari, Favorisen R. Lumbanraja, Warsono Warsono Dec 2024

Breast Cancer Area Identification In Mammograms Using Expectation Maximization Gaussian Mixture Model, Rizki Khoirun Nisa, Dian Kurniasari, Favorisen R. Lumbanraja, Warsono Warsono

Karbala International Journal of Modern Science

Breast cancer accounts for 25% of all cancer diagnoses and 16% of cancer-related deaths among women globally, with high mortality rates due to late diagnosis. Early detection relies on imaging techniques such as mammography, histopathology, and breast ultrasound, with mammography being the gold standard due to its proven to detect breast cancer, thus it is effective for breast cancer treatment. However, mammogram images often produce noise and artefacts, complicating early-stage cancer detection and emphasizing the need for advanced image processing. Clustering algorithms such as K-means and Expectation Maximization - Gaussian Mixture Model (EM-GMM) have shown potential in image segmentation. This …

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A Fast Federated Learning-Based Crypto-Aggregation Scheme And Its Simulation Analysis, Boshen Lü, Xiao Song Dec 2024

A Fast Federated Learning-Based Crypto-Aggregation Scheme And Its Simulation Analysis, Boshen Lü, Xiao Song

Journal of System Simulation

Abstract: To solve the problem of increased computation and communication costs caused by using homomorphic encryption (HE) to protect all gradients in traditional cryptographic aggregation (cryptoaggregation) schemes, a fast crypto-aggregation scheme called RandomCrypt was proposed. RandomCrypt performed clipping and quantization to fix the range of gradient values and then added two types of noise on the gradient for encryption and differential privacy (DP) protection. It conducted HE on noise keys to revise the precision loss caused by DP protection. RandomCrypt was implemented based on a FATE framework, and a hacking simulation experiment was conducted. The results show that the proposed …

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Critical Node Identification Method For Unmanned Aerial Vehicle Cluster Considering Localized Features, Chenglong Shi, Xiang Hua, Dong Wang, Jinjin Zhang, Tianqi Jiang, Yuanzhang Dang Dec 2024

Critical Node Identification Method For Unmanned Aerial Vehicle Cluster Considering Localized Features, Chenglong Shi, Xiang Hua, Dong Wang, Jinjin Zhang, Tianqi Jiang, Yuanzhang Dang

Journal of System Simulation

Abstract: Aiming at the problem that the UAV cluster critical node identification methods focus on the global network and ignore the correlation between nodes and their local features, a critical nodes identification method for unmanned aerial vehicle cluster considering local features is proposed. An unmanned aerial vehicle cluster network model is constructed based on complex network theory. The Laplacian energy is introduced to evaluate the importance of node within two hops, and information entropy is combined to evaluate the importance of node in a specific motif to comprehensive identify the critical nodes. Simulation results demonstrate that this method identifies critical …

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Optimization Of Urban Agglomeration Transportation Network Evacuation Paths, Bowei He, Chengbing Li, Shida Nie, Jialin Wang Dec 2024

Optimization Of Urban Agglomeration Transportation Network Evacuation Paths, Bowei He, Chengbing Li, Shida Nie, Jialin Wang

Journal of System Simulation

Abstract: Given the complexity of the internal transportation network structure within urban agglomerations and the presence of numerous alternative routes, this paper proposes an enhanced ant colony algorithm to address the evacuation path problem of urban agglomeration transportation networks. A comprehensive urban agglomeration transportation network model is constructed, in which the issue of virtual transfer edges within the urban scope is considered and a weighting function is constructed taking into account the travelling time cost and the transferring time cost. Optimizations are applied to the ant colony algorithm, constructing an adaptive adjustment of state transitions and an information pheromone update …

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Scientifically Improving Human-Nature Relationship In Desertification Areas, Bojie Fu, Yanxu Liu, Shuai Wang, Junfeng Song, Zejiang Li Dec 2024

Scientifically Improving Human-Nature Relationship In Desertification Areas, Bojie Fu, Yanxu Liu, Shuai Wang, Junfeng Song, Zejiang Li

Bulletin of Chinese Academy of Sciences (Chinese Version)

The expansion trend of desertification in China has been fundamentally restrained. In the new era, scientifically improving the relationship between human and nature in desertification areas to promote regional sustainable development has become an important demand for desertification combat in China. We summarize four key challenges to sustainable development in desertification areas, including increasing human demand on water, increasing land use intensity, increasing climatic risk, and insufficient industrial innovation. Based on the theoretical understanding of the coupling relationship between human and nature, the evolution of human-nature relationship in combating desertification can be divided into four stages, namely, extensive land exploitation, …

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Five Key Issues And Governance Strategies In Integration Of China’S National Computing Power, Tao Hong, Le Cheng Dec 2024

Five Key Issues And Governance Strategies In Integration Of China’S National Computing Power, Tao Hong, Le Cheng

Bulletin of Chinese Academy of Sciences (Chinese Version)

Computing power, as a core element of artificial intelligence, has not received sufficient research and attention compared to data and algorithms, and has become the short board of China in international artificial intelligence competition. In fact, the integrated construction of the arithmetic system is not only an inherent requirement for the development of the digital industry, but also a regular guide for the growth of the digital economy, and a core driver for the transformation of the digital society. Although it has always secured endorsement by national policy, the relevant legal norms and actual layout are still insufficient, and the …

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A Threat Assessment Method In Uncertain Dynamic Environments, Mei Yang, Bingkun Wang, Zhongjie Zhang, Yan Zeng, Jian Huang Dec 2024

A Threat Assessment Method In Uncertain Dynamic Environments, Mei Yang, Bingkun Wang, Zhongjie Zhang, Yan Zeng, Jian Huang

Journal of System Simulation

Abstract: A threat assessment method based on priori information and dynamic observation results is studied for the existence of dynamic uncertainty in complex war systems. The data mining is applied to obtain prior knowledge on the battlefield situation and construct an equipment-related confidence matrix. The sensor model is constructed to dynamically update the number of blue-side entities under the current situation by using the Bayesian method and considering both intelligence and observation results. The threat evaluation indicators and their weights are determined, and the TOPSIS method is used to finish the threat assessment. This method can well describe the complex …

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Research On Adaptive Scheduling Of Single-Arm Cluster Tools For Throughput Ratio Of Multiple Wafer Types With Concurrent Processing, Chunrong Pan, Yu Cui, Wenqing Xiong, Hao Zhou, Jiliang Luo Dec 2024

Research On Adaptive Scheduling Of Single-Arm Cluster Tools For Throughput Ratio Of Multiple Wafer Types With Concurrent Processing, Chunrong Pan, Yu Cui, Wenqing Xiong, Hao Zhou, Jiliang Luo

Journal of System Simulation

Abstract: Concurrent processing makes the wafer fabrication process prone to deadlocks and completion node ambiguity. A Petri net model is established to describe the system operation process by taking for the single-arm cluster tools for fully parallel processing of two wafer types as the research object, and a control strategy is developed to avoid the system deadlock. Based on the Petri net model, the temporal properties of the system is analyzed based on earliest starting strategy, and the action cycle sequence of robot is determined during the monitoring cycle for different scenarios of lot switching in a single production monitoring …

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Research On Latent Space-Based Anime Face Style Transfer And Editing Techniques, Haixin Deng, Fengquan Zhang, Nan Wang, Wancai Zhang, Jierui Lei Dec 2024

Research On Latent Space-Based Anime Face Style Transfer And Editing Techniques, Haixin Deng, Fengquan Zhang, Nan Wang, Wancai Zhang, Jierui Lei

Journal of System Simulation

Abstract: To address issues such as image distortion and style uniformity in existing anime style transfer networks within the field of image simulation, we propose the TGFE-TrebleStyleGAN (textguided facial editing with TrebleStyleGAN) for anime facial style transfer and editing. This framework leverages vector guidance within the latent space to generate facial imagery and incorporates a detail control module and a feature control module to constrain the aesthetic attributes of the generated images. The images generated by the transfer network serve as style control signals and constraints for fine-grained segmentation. Text-to-image generation technology captures correlations between styletransferred images and semantic information. …

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Research On Multi-Objective Gait Planning Of Biped Robot Based On Virtual Prototype, Yankai Zhang, Xuesong Wang, Yubin Jin, Dongsheng Zhang Dec 2024

Research On Multi-Objective Gait Planning Of Biped Robot Based On Virtual Prototype, Yankai Zhang, Xuesong Wang, Yubin Jin, Dongsheng Zhang

Journal of System Simulation

Abstract: A multi-objective gait optimization method based on virtual prototype is proposed to address the difficulty of balancing personalisation and performance in gait planning for bipedal robots. A scale prototype of a planar underactuated biped robot is created according to the body structure of Chinese people, and an identification approach is used to determine the robot's exact inertial parameters. A virtual prototype of the robot is created, and three optimization goals—speed, energy use, and stability are developed. Using the enhanced NSGA-II algorithm, the Pareto optimal solution set for the robot multi-objective gait planning issue is produced. Numerous gaits that conform …

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Intersection Braking Guidance For Trams Based On Lineside Signs, Wencong Tong, Jing Teng, Junxian Li, Xing Yao, Zhongjie Zhang Dec 2024

Intersection Braking Guidance For Trams Based On Lineside Signs, Wencong Tong, Jing Teng, Junxian Li, Xing Yao, Zhongjie Zhang

Journal of System Simulation

Abstract: Trams need to brake frequently due to signal control and safety speed limits at intersections. Due to the inaccuracy of distance judgment, tram drivers tend to reserve extra braking distance at intersections, resulting in lower braking coefficients and a decrease in speed. An intersection braking guidance method using lineside signs is proposed for trams to reduce braking distance redundancy and improve running speed. Drivers are guided to brake with the shortest possible distance by marking the initial braking position and speed of trams with fixed lineside signs. A tram driving simulation system was developed based on a vehicle dynamics …

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Interactions Of The Sars-Cov-2 Viral Genome 3’-Untranslated Region With Viral And Host Rnas, Caleb Frye, Mihaela Rita Mihailescu Dec 2024

Interactions Of The Sars-Cov-2 Viral Genome 3’-Untranslated Region With Viral And Host Rnas, Caleb Frye, Mihaela Rita Mihailescu

Electronic Theses and Dissertations

This dissertation focuses on the characterization of RNA-RNA interactions within the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome and with host microRNAs. As the causative agent of coronavirus disease 2019 (COVID-19), SARS-CoV-2 has evolved rapidly since its appearance. This has warranted prompt characterization of the virus particularly of its single stranded RNA (ssRNA) genome. By using a combination of bioinformatics, biophysics, and/or biological assays, we analyzed the SARS-CoV-2 viral genomic RNA and uncovered interactions of genomic RNA with host RNAs, highlighting an underutilized method of targeting RNA viruses. We showed here that the conserved elements in the viral genomic …

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Efficient Development Of Density-Insensitive Near-Infrared Methods For In-Line Drug Content Monitoring In Continuous Powder Streams, Natasha L. Velez-Silva Dec 2024

Efficient Development Of Density-Insensitive Near-Infrared Methods For In-Line Drug Content Monitoring In Continuous Powder Streams, Natasha L. Velez-Silva

Electronic Theses and Dissertations

A well-defined action plan to respond effectively to sudden changes in product demand is critical for preventing drug shortages within the pharmaceutical industry. An effective way to increase the output of a continuous manufacturing (CM) process is through flow rate adjustments. However, robust analytical methods must be in place to ensure consistent analytical performance across varying flow rates. Existing approaches for mitigating the physical effects of flow rate on Near-Infrared (NIR) measurements are often burdensome. Thus, efficient robust modeling strategies that reduce the current calibration burden and ensure model insensitivity to the physical variations in CM systems are needed. In …

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An Optimization Framework For Data Enrichment: A First Principles Approach To Designing Optimal Smoothers And Splines, Griffin Michael Kearney Dec 2024

An Optimization Framework For Data Enrichment: A First Principles Approach To Designing Optimal Smoothers And Splines, Griffin Michael Kearney

Dissertations - ALL

We develop a general framework for state estimation in systems modeled with stochastic dynamics and noisy measurements. Our approach is based on maximum likelihood estimation and employs a variety of techniques from optimization theory including the calculus of variations and discrete optimization to derive optimality conditions for many different types of problems. We make no rigid assumptions on the form of the mapping from measurements to state-estimate or on the distributions of the random processes, making the framework more general than existing techniques such as splines, Kalman smoothing or Gaussian Process Regressions, which are subject to limiting restrictions and modeling …

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Studies Towards The Synthesis Of A Simplified Forskolin Core And Phomactin A, Fortune Ononiwu Dec 2024

Studies Towards The Synthesis Of A Simplified Forskolin Core And Phomactin A, Fortune Ononiwu

Dissertations - ALL

Oxadecalins are privileged scaffolds found in various natural products that show biological activity, such as platelet aggregating factor antagonism and activation of adenyl cyclase. As such, various synthetic methods such as intramolecular substitution reactions and [4+2] cycloadditions have been developed for the construction of these important intermediates. Studies towards the synthesis of a simplified core of the labdane diterpene, forskolin, are described. Forskolin is the only known supplement to naturally raise cAMP levels, thereby displaying important pharmacological properties. The synthetic route described features a Lewis acid catalyzed dihydropyrone Diels-Alder reaction for rapidly assembly of the ABC tricycle. Modified Saegusa-Ito oxidation …

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