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Masters Theses

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Articles 31 - 60 of 2634

Full-Text Articles in Physical Sciences and Mathematics

Hydrophobic Deep Eutectic Solvents: Liquid-Liquid Extraction Of Organic Water Pollutants, Abigail Louise Maletta Apr 2024

Hydrophobic Deep Eutectic Solvents: Liquid-Liquid Extraction Of Organic Water Pollutants, Abigail Louise Maletta

Masters Theses

Pollution is a topic of significant research within the scientific community. The massive demand for industrial processes to deliver the technology and resources we rely on has opened numerous avenues for pollutants to enter the environment, affecting air, water, soil, and the food chain. Oftentimes, these pathways are intertwined, and the interplay between water and air currents spreads pollution globally, creating a cascade of environmental impacts. Water, a vital resource for all forms of life, is particularly susceptible to industrial pollution. Among the most prevalent water pollutants are heavy metals, such as lead and mercury, and organic compounds, often released …


Comparison Of Atmospheric Pressure Chemical Ionization And Electrospray Ionization Mass Spectrometry For The Direct Analysis Of Hops Bittering Compounds, Chhiring Sherpa Apr 2024

Comparison Of Atmospheric Pressure Chemical Ionization And Electrospray Ionization Mass Spectrometry For The Direct Analysis Of Hops Bittering Compounds, Chhiring Sherpa

Masters Theses

Hops acids are essential components in the beer brewing process containing alpha acids (α-acids) and beta acids (β-acids) as the major hops bittering compounds. Quantifying these acids is vital for quality control and determining bitterness levels and hops variety profiles. Current industry standards, like High-Performance Liquid Chromatography with Ultraviolet detection (HPLC-UV) and Ultraviolet Spectroscopy (UV-Vis), though effective, are time-consuming and solvent-intensive, providing incomplete information.

This research introduces a novel method using mass spectrometry with atmospheric pressure chemical ionization (APCI-MS) to analyze hops bittering acids without chromatographic separations. This approach offers rapid analysis, high throughput, and eco-friendliness.

Comparison with direct electrospray …


Fish Assemblage Structure In Great Lakes Coastal Wetlands Over Ten Years, Matthew S. Silverhart Jan 2024

Fish Assemblage Structure In Great Lakes Coastal Wetlands Over Ten Years, Matthew S. Silverhart

Masters Theses

Coastal wetlands in the Laurentian Great Lakes are important habitats for many fish species. The geographic scale of the watershed and the diversity of land uses in the region result in substantial environmental variation among coastal wetlands. During 2011-2020, annual surveys were conducted as part of the Great Lakes Coastal Wetland Monitoring Program (GLCWMP) to better understand the status and trends of coastal wetlands. Fish sampling consisted of fyke netting in monodominant vegetation zones. During this time, 1225 unique monodominant plant zones in coastal wetlands were sampled, resulting in 584,125 fishes captured that consisted of 113 different species. Yellow Perch …


Learn From The Past: Using Peer Data To Improve Course Recommendations In Personalized Education, Colton Walker Jan 2024

Learn From The Past: Using Peer Data To Improve Course Recommendations In Personalized Education, Colton Walker

Masters Theses

"This work describes a recommendation approach designed to enhance student success by identifying semester schedules and graduation paths. The primary objective is to provide personalized graduation path recommendations rooted in individual student performance and draw insights from the academic journeys of similar students who successfully graduated. The original research contribution of this work lies in the development of a graduation path recommender system that leverages a combination of Markov Decision Process, Q-Learning, and collaborative filtering techniques to pinpoint graduation paths with a higher likelihood of leading students to success based on their academic progress thus far. The effectiveness of the …


Time Series Anomaly Detection Using Generative Adversarial Networks, Shyam Sundar Saravanan Jan 2024

Time Series Anomaly Detection Using Generative Adversarial Networks, Shyam Sundar Saravanan

Masters Theses

"Anomaly detection is widely used in network intrusion detection, autonomous driving, medical diagnosis, credit card frauds, etc. However, several key challenges remain open, such as lack of ground truth labels, presence of complex temporal patterns, and generalizing over different datasets. In this work, we propose TSI-GAN, an unsupervised anomaly detection model for time-series that can learn complex temporal patterns automatically and generalize well, i.e., no need for choosing dataset-specific parameters, making statistical assumptions about underlying data, or changing model architectures. To achieve these goals, we convert each input time-series into a sequence of 2D images using two encoding techniques with …


Influence Of Attack Performance On The Ovc Volleyball Regular Seasons 2022 & 2023, Ignacio Valdemoros Jan 2024

Influence Of Attack Performance On The Ovc Volleyball Regular Seasons 2022 & 2023, Ignacio Valdemoros

Masters Theses

Understanding the outcome of volleyball games is necessary for coaches before, after, and during a season. There are several ways to gain this understanding, but statistical analysis is fundamental to see the minimum patterns of behavior that influence wins and losses in Volleyball. Furthermore, this analysis helps identify the optimal approach to achieving a goal and determining the most effective alternative to success. Scoring points in Volleyball involves three key skills: serving, blocking, and attacking. Among these skills, attacking plays the most relevant role in determining the outcome of a match. The position on the court (e.g. Outside Hitter, Middle …


Hysplit In Simulating The Atmospheric Dispersion Of Hazardous Aerosols: A Case Study In St. Louis, Missouri, Ahmet Tolga Odabasi Jan 2024

Hysplit In Simulating The Atmospheric Dispersion Of Hazardous Aerosols: A Case Study In St. Louis, Missouri, Ahmet Tolga Odabasi

Masters Theses

"Atmospheric dispersion and transmission play an important role in the behavior and effects of air pollution. Human health can be adversely affected by air pollution in a variety of ways, both immediately and over time. The Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) modeling program, a computer model and software package, tracks the transport trajectories and distributions of air pollution and various pollutants, including radioactive pollutants, in the atmosphere. It also facilitates research on pollution sources. This study simulated the transport of hazardous aerosols in St. Louis region for the years 2020, 2021, and 2022 using the HYSPLIT modeling …


Branching Fractional Brownian Motion, Reece Beattie-Hauser Jan 2024

Branching Fractional Brownian Motion, Reece Beattie-Hauser

Masters Theses

"Fractional Brownian Motion (FBM) is a Gaussian process whose increments are correlated over long times. FBM is an example of anomalous diffusion, and recently it has been used to model the distribution of serotonergic fibers in the brain [1, 2]. To better represent these fibers, branching FBM (bFBM), where FBM trajectories may randomly split into two, is introduced. One-dimensional bFBM is studied in both sub diffusive and super diffusive regimes, examining three potential behaviors of the correlations (memory) in a branching event: both trajectories retain the memory of previous steps, only one keeps the memory, and neither keeps the memory. …


Comparative Study Of Crypto Volatility And Price Forecasting Using A Mixture Of Time Series And Machine Learning Models, Abhishek Kafle Jan 2024

Comparative Study Of Crypto Volatility And Price Forecasting Using A Mixture Of Time Series And Machine Learning Models, Abhishek Kafle

Masters Theses

"Forecasting financial product volatility and price is crucial for informed decision-making in investment and risk management. The models considered include GARCH, LSTM, GRU, BiLSTM, and hybrid models that incorporate various combinations of these models. We present a comparative analysis of forecasting volatility and price using the aforementioned models.

We also introduce a user-friendly dashboard for model training and evaluation, enabling users to upload datasets and customize model parameters. The dashboard allows users to select the type of model, specify the dataset range for training, determine the number of epochs, adjust the number of layers for deep …


A New Proper Orthogonal Decomposition Method With Second Difference Quotients For The Wave Equation, Andrew Calvin Janes Jan 2024

A New Proper Orthogonal Decomposition Method With Second Difference Quotients For The Wave Equation, Andrew Calvin Janes

Masters Theses

"Recently, researchers have investigated the relationship between proper orthogonal decomposition (POD), difference quotients (DQs), and pointwise in time error bounds for POD reduced order models of partial differential equations. In \cite {Sarahs}, a new approach to POD with DQs was developed that is more computationally efficient than the standard DQ POD approach and it also retains the guaranteed pointwise in time error bounds of the standard method. In this thesis, we extend the new DQ POD approach from \cite {Sarahs} to the case of second difference quotients (DDQs). Specifically, a new POD method utilizing DDQs and only one snapshot and …


The Deep Bsde Method, Daniel Kovach Jan 2024

The Deep Bsde Method, Daniel Kovach

Masters Theses

"The curse of dimensionality is the non-linear growth in computing time as the dimension of a problem increases. Using the Deep Backwards Stochastic Differential Equation (Deep BSDE) method developed in [HJE18], I approximate the solution at an initial time to a one-dimensional diffusion equation. Although we only approximate a one-dimensional equation, this method extends well to higher dimensions because it overcomes the curse of dimensionality by evaluating the given partial differential equation along "random characteristics''. In addition to the implementation, I also present most of the mathematical theory needed to understand this method"-- Abstract, p. iii


Radiofrequency Interference Detection Using Lstmand Statistical Analysis Discriminator, Luke Smith Jan 2024

Radiofrequency Interference Detection Using Lstmand Statistical Analysis Discriminator, Luke Smith

Masters Theses

"Wireless devices are becoming increasingly pervasive across all aspects of society. Examples of such devices include radios, routers, mobile phones, tablets, and more. As the number of radio frequency (RF) devices continues to rise, so does the amount of interference and noise increase. This is why an efficient approach to interference detection is explored. Most research within this area has been done strictly within the frequency domain as viewing a signal within this domain provides many insights into what makes the signal. This has, however, led to the time domain being underutilized for this area of research.

To explore the …


Cryptographic Algorithms, Cryptocurrencies, And A Predictive Model Of Bitcoin Value By Pls Regression, Paul Kenneth O'Connor Jan 2024

Cryptographic Algorithms, Cryptocurrencies, And A Predictive Model Of Bitcoin Value By Pls Regression, Paul Kenneth O'Connor

Masters Theses

"With the invention of Bitcoin in 2009, as a seemingly timed response to the ongoing financial crisis, the popularity of the cryptocurrency has since continued to grow. Just this year, the Security Exchange Commission approved Bitcoin for exchange traded funds, allowing major investment firms to begin product trading. With this approval, and during this very moment of writing, Bitcoin has entered a bull market and reached a record value of over 72,000 USD. In addition, the Bitcoin halving event in April of 2024 is expected to increase demand even further. It has been anticipated that Bitcoin and other cryptocurrencies will …


The Geodetic Strain Rates From Gnss In The North American-Carribean-Cocos Triple Junction In Guatemala And Implications For Seismic Hazard, Tanaya Kashyap Jan 2024

The Geodetic Strain Rates From Gnss In The North American-Carribean-Cocos Triple Junction In Guatemala And Implications For Seismic Hazard, Tanaya Kashyap

Masters Theses

"Geodetic velocity data are pivotal for deciphering seismic risks, providing initial constraints for crustal surface strain rates. Gaining an understanding of the 2D surface strain tensor across an entire area necessitates knowledge of the surface velocity field, yet geodetic data such as measurements from the Global Navigation Satellite System (GNSS) are dispersed across the Earth’s surface. In the current scope of study, we have employed various methodologies to estimate strain rates in Guatemala, utilizing GNSS velocity data and leveraging the open-source Python tool Strain_2D. Strain_2D facilitates the computation of strain rates through diverse methods applied to the same dataset and …


The Exponential Function In Discrete Fractional Calculus Under The Delta Operator, Brayton James Link Jan 2024

The Exponential Function In Discrete Fractional Calculus Under The Delta Operator, Brayton James Link

Masters Theses

"Previously the exponential problem in discrete fractional calculus under the nabla operator was solved with the discrete Mittag--Leffler function. We now show the solution to the exponential problem in discrete fractional calculus under the delta operator, providing multiple derivations of the solution with recursion and Laplace transforms. We also share some computational and numerical results of experiments with different orders of difference to display the nature of the solution" -- Abstract, p. iii


Ontogenetically Driven Changes In The Endocranial Anatomy Of Maiasaura Peeblesorum And Its Implications For Sensory Functions, Emma Puetz Jan 2024

Ontogenetically Driven Changes In The Endocranial Anatomy Of Maiasaura Peeblesorum And Its Implications For Sensory Functions, Emma Puetz

Masters Theses

"Hadrosaurids exhibited extreme morphological diversity and behavioral characteristics that can be compared with other, closely related members of Dinosauria – particularly through the study of neuroanatomy. X-ray CT generated endocrania of the Late Cretaceous saurolophine hadrosaur Maiasaura peeblesorum, known as the “good mother” dinosaur, offers a unique opportunity to compare complex ecological behaviors between non-avian dinosaurs and their modern archosaur relatives. The 3D reconstruction software ORS Dragonfly provided linear and volumetric measurements taken from the digital cranial endocast and endosseous labyrinths of three ontogenetically varied M. peeblesorum specimens from the Two Medicine Formation in Montana that were used to …


Social Justice Mathematics: Classroom Practices That Give Students Rigor While Building Agency, Emily Marquise Dec 2023

Social Justice Mathematics: Classroom Practices That Give Students Rigor While Building Agency, Emily Marquise

Masters Theses

The purpose of this study is to examine the impact of a social justice approach to mathematics instruction. While many students have math aversion, students in low socioeconomic communities exhibit this to a higher degree putting them at a disadvantage as they progress through their educational career. More than 3.4 million K-12 students in the United States come from families that earn less than the median income yet achieve scores in the top percentile (Wyner et al., 2007). This raises the question of why so many students in low-socioeconomic settings are not given rigorous content that will keep them competitive …


Targeting Macrophytes: Increased Water Quality Through Optimized Vegetation Considerations For Constructed Wetlands, Austin Mcbrady Dec 2023

Targeting Macrophytes: Increased Water Quality Through Optimized Vegetation Considerations For Constructed Wetlands, Austin Mcbrady

Masters Theses

This study of constructed wetland design investigated relationships between macrophyte species selection and planting density for water quality improvement. A lab-scale wetland was compared against a pilot-scale wetland in San Antonio, Texas at Mitchell Lake to measure differences in effluent water quality improvement using three native macrophyte species. Using a novel, two-phase method, a targeting macrophyte was identified from among other species based on its marked capability for improving water quality factors, then was planted in varied majority densities to compare differences in treatment effectiveness. The results of this study showed that this complimentary approach to wetland design displayed significant …


Synthesis Of Block Copolymer Additives For Examining Phase Morphology And Improving Mechanical Properties Of Thermoplastics Elastomers., Bishal Upadhyay Dec 2023

Synthesis Of Block Copolymer Additives For Examining Phase Morphology And Improving Mechanical Properties Of Thermoplastics Elastomers., Bishal Upadhyay

Masters Theses

Polystyrene-block-poly(1,4-butaidene)-block-polystyrene (PS-PB-PS) triblock copolymers are one of the most widely studied thermoplastic elastomers (TPEs) due to their ease of synthesis, non-polar nature, and commercial applicability. Like many block copolymers, incompatibility between PS and PB causes these TPEs to undergo microphase segregation. Many studies have examined the mechanical properties of blends of TPEs and PS homopolymer additives. However, there have been few studies focused on understanding the morphology and mechanical properties of blends of TPEs and copolymer additives with different architectures. Herein, I describe the synthesis of linear and graft copolymer additives based on the random copolymers poly(methyl methacrylate-random-cyclohexyl methacrylate) (PrC). …


The Impacts Of Tilled-In Biodegradable Plastic Mulch On Soil Microbial Communities, Corissa L. Martin Dec 2023

The Impacts Of Tilled-In Biodegradable Plastic Mulch On Soil Microbial Communities, Corissa L. Martin

Masters Theses

Plastics mulch films are used in agriculture to help increase crop production by regulating soil water retention and soil temperature while also preventing weed growth. Despite these benefits, plastic mulches have led to higher levels of microplastic pollution as weathering occurs. In response to this issue, biodegradable plastic mulches (BDMs) have been introduced to help reduce plastic pollution as they are designed to be tilled into soil after each growing season to continue degradation. Degradation of these mulch films is dependent on climate and, in some areas, complete degradation can take years. Since some biodegradable plastic mulches are made of …


Assessing The Effects Of The Spring Hunting Season Start Date On Wild Turkey Seasonal Productivity And Hunter Behavior, Joseph Quehl Dec 2023

Assessing The Effects Of The Spring Hunting Season Start Date On Wild Turkey Seasonal Productivity And Hunter Behavior, Joseph Quehl

Masters Theses

Many states throughout the Southeast have documented declines in wild turkey (Meleagris gallopavo) harvest and estimates of recruitment in poult-per-hen ratios. Wild turkey populations are driven by seasonal productivity, so the decline in these parameters may indicate a decline in the overall population. One hypothesis as to why we are seeing a reduction in productivity and a potential population decline is that the spring hunting season is disrupting the reproductive cycle by harvesting too many males before they have had the opportunity to breed, or by harvesting dominant males and disrupting the social hierarchy of the flock. Our …


The Influence Of Ion-Ion Correlations On Conductivity In Concentrated Ionic Systems, Md Dipu Ahmed Dec 2023

The Influence Of Ion-Ion Correlations On Conductivity In Concentrated Ionic Systems, Md Dipu Ahmed

Masters Theses

This study delves into the fascinating realm of concentrated ionic systems, such as ionic liquids, superionic materials, organic ionic plastic crystals, and polyelectrolytes, which hold immense potential for energy storage applications. The focus is on understanding the intricate role of ionic correlations in shaping their ionic conductivity behavior. These correlations can either boost or impede conductivity, yet their underlying mechanisms remain elusive. Through extensive investigation of various materials, including ionic liquids with differing anionic masses, pure organic ionic plastic crystals, and doped systems, this research employs advanced techniques like dielectric spectroscopy and innovative momentum conservation models to quantify these correlations. …


Intrusion Detection: Machine Learning Techniques For Software Defined Networks, Jacob S. Rodriguez Aug 2023

Intrusion Detection: Machine Learning Techniques For Software Defined Networks, Jacob S. Rodriguez

Masters Theses

In recent years, software defined networking (SDN) has gained popularity as a novel approach towards network management and architecture. Compared to traditional network architectures, this software-based approach offers greater flexibility, programmability, and automation. However, despite the advantages of this system, there still remains the possibility that it could be compromised. As we continue to explore new approaches to network management, we must also develop new ways of protecting those systems from threats. Throughout this paper, I will describe and test a network intrusion detection system (NIDS), and how it can be implemented within a software defined network. This system will …


Unsupervised Machine Learning Of Tornado-Producing Storms In The Southeastern United States, Morgan R. Steckler Aug 2023

Unsupervised Machine Learning Of Tornado-Producing Storms In The Southeastern United States, Morgan R. Steckler

Masters Theses

The east-southeastern US is uniquely affected by storm and tornado-related damages, costs, injuries, and deaths. Based on doppler radar, satellite, and modeled data, previous research sought to understand these different types of storms that produce strong tornadoes. Many approaches to storm classification are time intensive, complex, and vary significantly across the literature. The purpose of this work is to (1) explore the radar-derived data structure and spread of strong tornado-producing mesoscale storms in the east-southeastern US; (2) use K-Means unsupervised machine learning methods to elucidate clusters (storm types) and clustering attributes; and (3) assess the utility of K-Means as a …


Phosphatase Enzyme-Responsive Synthetic Lipids For Liposome Immolation Towards Enhanced Cargo Release, Justin Thomas Kirby Aug 2023

Phosphatase Enzyme-Responsive Synthetic Lipids For Liposome Immolation Towards Enhanced Cargo Release, Justin Thomas Kirby

Masters Theses

Liposomal nanoscale delivery vehicles have been shown to aid in the delivery of therapeutic cargo due to their ability to encapsulate and improve the pharmacokinetic properties of a range of drug molecules. However, liposome therapeutic potential could be enhanced by exerting greater control over liposome cargo delivery and release. This is being pursued by designing lipids that are able to respond to specific stimuli, particularly those overexpressed in diseased cells. In this thesis, we describe stimuli-responsive liposomes in which the enzyme alkaline phosphatase is used as the stimulus. This trigger was selected since this enzyme is overexpressed in certain cancer …


Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link Aug 2023

Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link

Masters Theses

Concentrations, compositions, and variability of Per- and Polyfluoroalkyl Substances (PFAS) in sewage sludge are characterized using an extensive dataset of 350 samples from 190 wastewater treatment plants (WWTPs) across Michigan. All samples are comprised of final treated sewage sludge generated at the end of the wastewater treatment process. Concentrations of Σ24 PFAS are log normally distributed with a range of 1 to 3200 ng/g dry wt. and of average 108 ± 277 ng/g dry wt. Compounds with carboxyl and sulfonic functional groups comprised 29% and 71% of Σ24 PFAS concentrations, respectively, on average. Primary sample variability is associated …


Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link Aug 2023

Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link

Masters Theses

Concentrations, compositions, and variability of Per- and Polyfluoroalkyl Substances (PFAS) in sewage sludge are characterized using an extensive dataset of 350 samples from 190 wastewater treatment plants (WWTPs) across Michigan. All samples are comprised of final treated sewage sludge generated at the end of the wastewater treatment process. Concentrations of Σ24 PFAS are log normally distributed with a range of 1 to 3200 ng/g dry wt. and of average 108 ± 277 ng/g dry wt. Compounds with carboxyl and sulfonic functional groups comprised 29% and 71% of Σ24 PFAS concentrations, respectively, on average. Primary sample variability is associated with …


Numerical And Experimental Constraints On Trace Element Fractionation During Lunar Magma Ocean Solidification, Dian Ji Aug 2023

Numerical And Experimental Constraints On Trace Element Fractionation During Lunar Magma Ocean Solidification, Dian Ji

Masters Theses

Traditional lunar magma ocean (LMO) theory suggests the anorthositic lunar crust formed by floating of buoyant plagioclase, one of the major products of LMO solidification, on the surface of LMO. To test this model, after applying experimentally determined LMO solidification sequences, we compared calculated Rare Earth Element (REE) concentrations of lunar plagioclase to plagioclase in Apollo ferroan anorthosites and lunar anorthositic meteorites. Several initial LMO compositions, and lunar-relevant mineral-melt partition coefficient predictive models were tested (where the partition coefficient is the concentration ratio of a specific element between two phases). Compared with plagioclase in the natural samples, modeled plagioclase directly …


Metagenomic Profiling Of Cave Biofilms, With A Focus On Chemolithoautotrophy And Pseudonocardiaceae, John A. Fulginiti Aug 2023

Metagenomic Profiling Of Cave Biofilms, With A Focus On Chemolithoautotrophy And Pseudonocardiaceae, John A. Fulginiti

Masters Theses

The dark, humid, and nutrient depleted conditions of caves set limitations on habitability and result in microbial diversity and community structures that differ from surface environments. Recent studies investigating cave microbiomes reveal that Pseudonocardiaceae, a family of bacteria belonging to the phylum Actinomycetota, are abundant in cave sediment and on rocks as subaerial biofilms, however little work has been done on attempting to characterize their diversity and metabolism within the environment. This study used shotgun metagenomics to characterize the functional potential of Pseudonocardiaceae, as well as other cave microbes, in cave site KN14 located in Knox County, Tennessee. Functions of …


Expression And Purification Of Polyketide Synthase Domains To Investigate Protein-Protein Interactions In Polyketide Biosynthetic Pathways, Mujeeb Adeyinka Wakeel Aug 2023

Expression And Purification Of Polyketide Synthase Domains To Investigate Protein-Protein Interactions In Polyketide Biosynthetic Pathways, Mujeeb Adeyinka Wakeel

Masters Theses

Polyketide synthases (PKSs) are multienzyme proteins catalyzing the production of the polyketide class of natural products with vast structural diversity. Type II PKSs catalyze polyketide biosynthesis using discrete (standalone) enzymes (domains), while type I PKSs use covalently linked enzymes arranged in a module to catalyze polyketide production. It is hypothesized that type II PKSs are the precursors to type I PKSs, proposing that the genes encoding individual discrete enzymes in type II PKSs fused to give the multienzyme modules of type I PKSs. We reasoned that the intramolecular-like reactions occurring in type I PKS modules might be a driving force …