Physical Sciences and Mathematics Commons^™

Droughts Of The Twentieth And Early Twenty First Centuries: Influences On The Production Of Beef And Forage In Kentucky, Usa, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

An Effective Computational Method Incorporating Multiple Secondary Structure Predictions In Topology Determination For Cryo-Em Images, Abhishek Biswas, Desh Ranjan, Mohammad Zubair, Stephanie Zeil, Kamal Al Nasr, Jing He

Computer Science Faculty Publications

A key idea in de novo modeling of a medium-resolution density image obtained from cryo-electron microscopy is to compute the optimal mapping between the secondary structure traces observed in the density image and those predicted on the protein sequence. When secondary structures are not determined precisely, either from the image or from the amino acid sequence of the protein, the computational problem becomes more complex. We present an efficient method that addresses the secondary structure placement problem in presence of multiple secondary structure predictions and computes the optimal mapping. We tested the method using 12 simulated images from alpha-proteins and …

Freshwater Future: The Influence Of Exposure To Extreme Summer Rainfall Events On The Resistance And Recovery Patterns Of An Estuarine Seagrass, Chanelle Webster

Theses : Honours

Restoring and maintaining the ecological resilience of seagrass ecosystems will be a major challenge of the 21st century. The decline of seagrasses worldwide is attributed to the erosion or elimination of their ecological resilience driven by human impacts, extreme climate events and climate change. Ecological resilience refers to the ability of ecosystems to resist or recover from disturbances whilst maintaining their integral structure and function. Seagrass resilience is influenced by life history, meadow form (transitory or enduring) and habitat type. The purpose of this honours project was to investigate the influence of extreme climate events and meadow form on a …

H-Binder: A Hardened Binder Framework On Android Systems, Dong Shen, Zhangkai Zhang, Xuhua Ding, Zhoujun Li, Robert H. Deng

Research Collection School Of Computing and Information Systems

The Binder framework is at the core of Android systems due to its fundamental role for interprocess communications. Applications use the Binder to perform high level tasks such as accessing location information. The importance of the Binder makes it an attractive target for attackers. Rootkits on Android platforms can arbitrarily access any Binder transaction data and therefore have system-wide security impact. In this paper, we propose H-Binder to secure the Binder IPC channel between two applications. It runs transparently with Android and COTS applications without making changes on their binaries. In this work, we design a bare-metal ARM hypervisor with …

Synthetic Methods For Ester Bond Formation And Conformational Analysis Of Ester-Containing Carbohydrates, Sven Hackbusch

University of the Pacific Theses and Dissertations

This dissertation encompasses work related to synthetic methods for the formation of ester linkages in organic compounds, as well as the investigation of the conformational influence of the ester functional group on the flexibility of inter-saccharide linkages, specifically, and the solution phase structure of ester-containing carbohydrate derivatives, in general.

Stereoselective reactions are an important part of the field of asymmetric synthesis and an understanding of their underlying mechanistic principles is essential for rational method development. Here, the exploration of a diastereoselective O-acylation reaction on a trans-2-substituted cyclohexanol scaffold is presented, along with possible reasons for the observed reversal of stereoselectivity …

Imaging Bioturbation In Supratidal Carbonates: Non-Invasive Field Techniques Enhance Neoichnological And Zoogeomorphological Research, San Salvador, The Bahamas, Karen Kopcznski, Ilya Buynevich, H. Allen Curran, Jon Caris, Jonathan Nyquist

Geosciences: Faculty Publications

A case study in unconsolidated carbonates on San Salvador Island, The Bahamas, utilized high-frequency (800 MHz) georadar imaging to augment existing methodologies (burrow counts and measurements, casting) in brachyuran bioturbation research (Ocypode quadrata and Gecarcinus lateralis), and as part of a new dataset characterizing blue land crab (Cardisoma guanhumi) burrows. Non-invasive techniques such as ground-penetrating radar (GPR) can complement traditional field surveys aimed at quantifying mesoscale bioturbation in modern settings. These methods can establish diagnostic features for tracemaker identification and refine existing ichnofacies models. Drone-mounted aerial coverage provided the first high-resolution images of the micro-topography and …

Post-Rift Magmatic Evolution Of The Eastern North American “Passive-Aggressive” Margin, Sarah E. Mazza, Esteban Gazel, Elizabeth A. Johnson, Michael Bizimis, Ryan Mcaleer, C. Berk Biryol

Geosciences: Faculty Publications

Understanding the evolution of passive margins requires knowledge of temporal and chemical constraints on magmatism following the transition from supercontinent to rifting, to post-rifting evolution. The Eastern North American Margin (ENAM) is an ideal study location as several magmatic pulses occurred in the 200 My following rifting. In particular, the Virginia-West Virginia region of the ENAM has experienced two postrift magmatic pulses at ∼152 Ma and 47 Ma, and thus provides a unique opportunity to study the long-term magmatic evolution of passive margins. Here we present a comprehensive set of geochemical data that includes new Ar/ Ar ages, major and …

Rescue And Rehabilitation Of An Indian Rock Python (Python Molurus): First Case Study From Pakistan, Fida Muhammad Khan, Fakhar-I- Abbas, Adila Nazli, Madeeha Manzoor, Zahid Iqbal Khan

Journal of Bioresource Management

Pythons are facing the threat of extinction due to human annihilation and interference in natural habitats of pythons. Indian rock python (Python molurus) has been stated as Lower Risk/Near Threatened by International Union for the Conservation of Nature (IUCN). Therefore, there is an intense need to change the perception of people and encourage them to coincide with this big snake. Current study involved the rescue and rehabilitation of an Indian rock python (P. molurus) spotted at the shrine of Baba Shah Jeevan, Rawalpindi, Pakistan. Python was grasped by skilled snake catchers and taken to the wildlife …

Life In Hampton Roads Survey Press Release #5: Sea Level Rise And Flooding, Social Science Research Center, Old Dominion University

Life in Hampton Roads Survey Report

[Introductory paragraph]

This report examines regional measures of environmental risk perceptions from the 2017 Life In Hampton Roads survey (LIHR 2017) conducted by the Old Dominion University Social Science Research Center. Data from prior years is also provided when available to show comparisons in responses over time. Responses were weighted by city population, race, age, gender, and phone usage (cell versus land-line) to be representative of the Hampton Roads region.

Dynamics Of Gene Networks In Cancer Research, Paul Scott

College of Graduate Studies: Theses & Dissertations

Cancer prevention treatments are being researched to see if an optimized treatment schedule would decrease the likelihood of a person being diagnosed with cancer. To do this we are looking at genes involved in the cell cycle and how they interact with one another. Through each gene expression during the life of a normal cell we get an understanding of the gene interactions and test these against those of a cancerous cell. First we construct a simplified network model of the normal gene network. Once we have this model we translate it into a transition matrix and force changes on …

A Journey To Fuzzy Rings, Brett T. Ernst

College of Graduate Studies: Theses & Dissertations

Enumerative geometry is a very old branch of algebraic geometry. In this thesis, we will describe several classical problems in enumerative geometry and their solutions in order to motivate the introduction of tropical geometry. Finally, fuzzy rings, a powerful algebraic framework for tropical and algebraic geometry is introduced.

Asymmetric Membranes For High Capacity Lithium-Ion Battery Electrodes, Ian Byrd

College of Graduate Studies: Theses & Dissertations

Lithium-Ion Batteries (LIBs) have broad applications such as portable electronic devices, electric vehicles, and for green energy storage from intermittent sources. Current LIBs are limited by their low capacity materials at both the anode and cathode. At the anode, graphite suffers from a low capacity of only 372 mAh g^-1. The most commonly used cathode material is LiCoO₂ which has a meager capacity of 140 mAh g^-1. Thereby the broader applications of LIBs are limited due to these low capacities. It is imperative to develop higher capacity materials to further improve the performance of LIBs. …

Adrc Based Control Of Nonlinear Dynamical System With Multiple Sources Of Disturbance And Multiple Inputs, Chan Mi Park

College of Graduate Studies: Theses & Dissertations

In this thesis, we study the stability of Active Disturbance Rejection Control (ADRC) applied to controlling the Lorenz system. The Lorenz system is a nonlinear dynamical system that we attempt to control. In fact, the system is used to model convection flow such as that found in thermosyphons, electric circuits, and lasers. We are stabilizing the Lorenz system along with a few disturbances. Thus, to stabilize this chaotic system, a robust controller is required. The ADRC system is known as as effective method to stabilize a dynamical system. With the help of the Extended State Observer (ESO), the system can …

Α-Eleostearic Acid Extraction By Saponification Of Tung Oil And Its Subsequent Polymerization, Amanda Murawski

College of Graduate Studies: Theses & Dissertations

The goal of environmentally sound research is to provide alternatives that are more sustainable and renewable, such as vegetable oil-based polymers, than the current petroleum-based products. Vegetable oil-based polymers have received a lot of attention recently due their multifaceted properties, which are simply achieved by adjusting the monomer or resin composition. The carbon-carbon double bonds in unsaturated oils are ideal reactive sites for the free radical or cationic polymerizations. Most vegetable oils must be modified before polymerization due to the low reactivity of their non-conjugated fatty acid chains. Tung oil (TO) contains ~83% of a triply conjugated fatty acid ( …

Optimization Methods For Tabular Data Protection, Iryna Petrenko

College of Graduate Studies: Theses & Dissertations

In this thesis we consider a minimum distance Controlled Tabular Adjustment (CTA) model for statistical disclosure limitation (control) of tabular data. The goal of the CTA model is to find the closest safe table to some original tabular data set that contains sensitive information. The measure of closeness is usually measured using l₁ or l₂ norm; with each measure having its advantages and disadvantages. According to the given norm CTA can be formulated as an optimization problem: Liner Programing (LP) for l₁, Quadratic Programing (QP) for l₂. In this thesis we present an alternative …

Applications Of Flow Network Models In Finance, Angel J. Woods

College of Graduate Studies: Theses & Dissertations

In this thesis we explore the applications of flow networks in practical problems in finance. After introducing basic definitions and background information, we first survey some known applications of flow networks in theoretical mathematics. We also briefly comment on their potential applications in the setting of financial flow networks. We then construct networks from practical financial flows and present the construction, reasoning, and known applications. Lastly, we show a design of financial flow networks that takes time into consideration and discuss its applications.

Pattern Containment In Circular Permutations, Charles Lanning

College of Graduate Studies: Theses & Dissertations

Pattern containment in permutations, as opposed to pattern avoidance, involves two aspects. The first is to contain every pattern at least once from a given set, known as finding superpatterns; while the second is to contain some given pattern as many times as possible, known as pattern packing. In this thesis, we explore these two questions in circular permutations and present some interesting observations. We also raise some questions and propose some directions for future study.

Examining And Exposing The Darknet, Ton H. Don

College of Graduate Studies: Theses & Dissertations

This thesis consists of two studies; the first study is “Diving into the Darknet” and the second is “Exposing the Darknet on Mobile Devices”. The Darknet is a network of hidden sites and services which are built based on anonymity. In “Diving into the Darknet”, we applied different data science methods to establish the relationships between the data in the data set. This data set has information related to seller, drug types, and transactions. Additionally, we used Tableau to visualize the data set. For the second study, we took a digital forensics perspective of the Darknet. Orfox and Orbot, a …

Quasi-Random Action Selection In Markov Decision Processes, Samuel D. Walker

College of Graduate Studies: Theses & Dissertations

In Markov decision processes an operator exploits known data regarding the environment it inhabits. The information exploited is learned from random exploration of the state-action space. This paper proposes to optimize exploration through the implementation of quasi-random sequences in both discrete and continuous state-action spaces. For the discrete case a permutation is applied to the indices of the action space to avoid repetitive behavior. In the continuous case sequences of low discrepancy, such as Halton sequences, are utilized to disperse the actions more uniformly.

Modeling Volatility Of Financial Time Series Using Arc Length, Benjamin H. Hoerlein

College of Graduate Studies: Theses & Dissertations

This thesis explores how arc length can be modeled and used to measure the risk involved with a financial time series. Having arc length as a measure of volatility can help an investor in sorting which stocks are safer/riskier to invest in. A Gamma autoregressive model of order one(GAR(1)) is proposed to model arc length series. Kernel regression based bias correction is studied when model parameters are estimated using method of moment procedure. As an application, a model-based clustering involving thirty different stocks is presented using k-means++ and hierarchical clustering techniques.

Oasis - Identifying The Core Attributes For Rdbms Alternatives, Benjamin P. Mcpherson

College of Graduate Studies: Theses & Dissertations

Since their introduction in the 1970s, relational database management systems have served as the dominate data storage technology. However, the demands of big data and Web 2.0 necessitated a change in the market, sparking the beginning of the NoSQL movement in the late 2000s. NoSQL databases exchanged the relational model and the guaranteed consistency of ACID transactions for improved performance and massive scalability [1]. While the benefits NoSQL provided proved useful, the lack of sufficient SQL functionality presented a major hurdle for organizations which require it to properly operate. It was clear that new RDBMS solutions which did not compromise …

Audio-Based Productivity Forecasting Of Construction Cyclic Activities, Chris A. Sabillon

College of Graduate Studies: Theses & Dissertations

Due to its high cost, project managers must be able to monitor the performance of construction heavy equipment promptly. This cannot be achieved through traditional management techniques, which are based on direct observation or on estimations from historical data. Some manufacturers have started to integrate their proprietary technologies, but construction contractors are unlikely to have a fleet of entirely new and single manufacturer equipment for this to represent a solution. Third party automated approaches include the use of active sensors such as accelerometers and gyroscopes, passive technologies such as computer vision and image processing, and audio signal processing. Hitherto, most …

Potential For Scaling Up Climate Smart Agricultural Practices: Examples From Sub-Saharan Africa, Kindie Tesfaye, Menale Kassie, Jill E. Cairns, Misiko Michael, Clare Stirling, Tsedeke Abate, B. M. Prasanna, Mulugetta Mekuria, Habtamu Hailu, Dil Bahadur Rahut, Olaf Erenstein, Bruno Gerard

All Peer-Reviewed Publications

Agriculture in Sub-Saharan Africa (SSA) is predominantly rain-fed, and erratic weather patterns and extreme weather events, exacerbated by the changing climate, adds to the challenges faced by smallholder farmers in producing enough food to feed the ever growing population of the region. While the farming communities are responding to these challenges, there is an intensive need for scaling-up adoption of appropriate interventions that can help increase crop yields and resilience to climate change. A review and analysis of potential climate-smart agricultural practices (CSAs) in SSA indicate that some CSAs are increasingly adopted by farmers and show potential for scaling up. …

Mursamacin: A Novel Class Of Antibiotics From Soil-Dwelling Roundworms Of Central Kenya That Inhibits Methicillin-Resistant Staphylococcus Aureus, Ryan Musumba Awori, Peter Njenga Ng'ang'a, Lorine Nanjala Nyongesa, Nelson Onzere Amugune, Daniel Masiga

All Peer-Reviewed Publications

Antibiotic-resistant bacteria, also called " superbugs", can at worst retrogress modern medicine to an era where even sore throats resulted in death. A solution is the development of novel types of antibiotics from untapped natural sources. Yet, no new class of antibiotic has been developed in clinical medicine in the last 30 years. Here, bacteria from insect-killing Steinernema roundworms found in the soils of Central Kenya were isolated and subjected to specific molecular identification. These were then assayed for production of antibiotic compounds with potential to treat methicillin-resistant Staphylococcus aureus infections. The bacteria were identified as Xenorhabdus griffiniae and produced …

Entomopathogens Routinely Used In Pest Control Strategies: Orchards In Tropical Climate, N. K. Maniania, S. Ekesi, C. Dolinski

All Peer-Reviewed Publications

Fruit and nut trees such as mango, pineapples, papaya, banana, guava, cashew, passion fruit, and avocado are important components of tropical ecosystems. They are sources of vitamins, minerals and carbohydrates and have great economic importance as sources of both household incomes and national revenues. Fruit and nut trees provide important adaptive values and tend to be more resilient to climate change due to their perennial nature, and they have the property of sequestering carbon. World production and trade of fresh tropical fruit are expected to expand over decades, with developing countries accounting for about 98% of total production, while developed …

Angiostoma Norvegicum N. Sp. (Nematoda: Angiostomatidae) A Parasite Of Arionid Slugs In Norway, Jenna L. Ross, Solveig Haukeland, Bjørn A. Hatteland, Elena S. Ivanova

All Peer-Reviewed Publications

Angiostoma norvegicum n. sp. (Angiostomatidae) is described from the oesophagus, crop and the buccal mass of five species of slugs of the family Arionidae, Arion vulgaris (Moquin-Tandon), Arion ater (L.), Arion fasciatus (Nilsson), Arion fuscus (Müller) and Arion rufus/Arion ater hybrid), collected throughout Norway. Angiostoma norvegicum n. sp. was found parasitising arionids at seven of the 30 sample sites examined (23.3%), and 9.9% of all Arion spp. were infected with this nematode. The new species is characterised by its large size (4.0–8.6 mm long) and in having: lateral alae; 6 + 6 papillae at the cephalic end; a large circular …

The Plant As A Habitat For Entomophagous Insects, L. Kaiser, P. Ode, S. Van Nouhuys, P. A. Calatayud, S. Colazza, A. M. Cortesero, A. Thiel, J. Van Baaren

All Peer-Reviewed Publications

Populations of herbivorous insects are naturally consumed by other predacious or predatory insect species. These entomophagous insects are thus plant-dwelling organisms that use the plant for several vital functions and are affected by plant traits at the evolutionary, organism and population levels. Many entomophagous species are used for the biological control of insect pests worldwide. The aim of this chapter is to provide an exhaustive review of mechanisms underlying the interactions between plants and entomophagous insects, including those governing life history traits at the individual level, as well as those acting on population and community structure and dynamics. We detail …

Estimating Swiss Chard Foliar Macro- And Micronutrient Concentrations Under Different Irrigation Water Sources Using Ground-Based Hyperspectral Data And Four Partial Least Squares (Pls)-Based (Pls1, Pls2, Spls1 And Spls2) Regression Algorithms, Elfatih M. Abdel-Rahman, Onisimo Mutanga, John Odindi, Elhadi Adam, Alfred Odindo, Riyad Ismail

All Peer-Reviewed Publications

Timely information on crop foliar nutrient content provides a measure of crop nutritional and vitality status. Growers and farm managers use such information for precision crop management such as an appropriate fertilizer application to correct for any crop nutrient deficiencies at identified hotspots. Foliar heavy nutrient content could also be a direct indicator of crops having been polluted from the surroundings, which may be a result of heavy metals absorbed from, among others, contaminated soils and waste water. In the present study, we explored the potential use of four partial least squares (PLS)-based regression algorithms for estimating foliar Swiss chard …

Visualizing Morphogenesis With The Processing Programming Language, Avik Patel, Amar Bains, Richard Millet, Tamira Elul

Faculty Publications & Research of the TUC College of Osteopathic Medicine

We used Processing, a visual artists’ programming language developed at MIT Media Lab, to simulate cellular mechanisms of morphogenesis – the generation of form and shape in embryonic tissues. Based on observations of in vivo time-lapse image sequences, we created animations of neural cell motility responsible for elongating the spinal cord, and of optic axon branching dynamics that establish primary visual connectivity. These visual models underscore the significance of the computational decomposition of cellular dynamics underlying morphogenesis.

Response And Recovery Of A Mixed Tropical Seagrass Assemblage To Variation In The Frequency And Magnitude Of Light Deprivation. Report Of Theme 5 - Project 5.5.3 Prepared For The Dredging Science Node, John Statton, Kathryn Mcmahon, Rosin Mccallum, Gary Kendrick, Paul Lavery

Research outputs 2014 to 2021

The capacity of seagrasses to cope with episodes of light deprivation from overlying turbid waters may not only depend on the absolute quantity of light they receive during that episode, but also on how the light deprivation varies through time. For example, turbidity and therefore light reduction may be relatively constant over the episode or it may fluctuate depending on the frequency of pulsed turbidity events.

This report presents findings from a controlled mesocosm experiment that aimed to determine the responses of seagrasses to, and recovery from, differences in the pattern of the delivery of light. The study focussed on …