Physical Sciences and Mathematics Commons^™

Sharing The Salt Bowl: Counterion Identity Drives N-Alkyl Resorcinarene Affinity For Pyrophosphate In Water, Kwaku Twum, Seyed Iraj Sadraei, Jordan Feder, S. Maryamdokht Taimoory, Kari Rissanen, John F. Trant, Ngong Kodiah Beyeh

Chemistry and Biochemistry Publications

N-Alkyl ammonium resorcinarene chloride receptors, NARX4, have been shown to act as high-sensitivity detectors of pyrophosphate (PPi), a biomarker of disease, in aqueous media through the chloride-to-PPi exchange [NAR(Cl)4 to NARPPi]. The nature of the anion of the macrocyclic NARX4 (X = Cl−, Br−, triflate OTf−) receptor greatly influences the PPi-affinity in aqueous media. The binding affinity for [NAR (Cl)4] is 3.61 × 105 M−1, while the NAR (Br)4 and NAR (OTf)4 show stronger binding of 5.30 × 105 M−1, and 6.10 × 105 M−1, respectively. The effects of upper rim ammonium cation, –N+H2R substituents (R = 3-hydroxypropyl, cyclohexyl, …

Reaction Of Alkynyl- And Alkenyltrifluoroborates With Propargyldicobalt Cations: Alkynylation, Alkenylation, And Cyclopropanation Product Pathways, Brent St Onge, S. Maryamdokht Taimoory, Jeffrey Battersby, John F. Trant, James R. Green

Chemistry and Biochemistry Publications

The Lewis acid-mediated Nicholas reactions of propargyl acetate–Co2(CO)6 complexes with a series of potassium alkynyltrifluoroborates and potassium alkenyltrifluoroborates are described. Alkynyltrifluoroborates directly alkynylate the intermediate propargyldicobalt cations. In contrast, alkenyltrifluoroborates proceed through one of the three modes of dominant reactivity: C-2-substituted alkenyltrifluorobrates directly alkenylate, predominantly with the retention of stereochemistry. C-1-substituted alkenyltrifluoroborates alkenylate at C-2. Potassium vinyltrifluoroborate incorporates a cyclopropane at the site propargyl to alkynedicobalt. Computational analysis of these systems explains the differential modes of reactivity of alkenyltrifluoroborates and outlines the probable mechanisms for the formation of each product.

Protocol For Fabricating Electroless Nickel Immersion Gold Strain Sensors On Nitrile Butadiene Rubber Gloves For Wearable Electronics, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

This protocol describes the fabrication of patterned conductive gold films on nitrile butadiene rubber (NBR) gloves for wearable strain sensors using electroless nickel immersion gold (ENIG) plating, a solution-based metallization technique. The resulting NBR/ENIG films are strain sensitive; resistance measurements of a patterned sensing array can be used to map human hand motions. This protocol also describes challenges related to the ENIG process and troubleshooting steps to achieve conformal gold films for strain sensing over a large working range. For complete details on the use and execution of this protocol, please refer to Mechael et al. (2021).

Synergistic Broad-Spectrum Antibacterial Activity Of Hypoxis Hemerocallidea-Derived Silver Nanoparticles And Streptomycin Against Respiratory Pathobionts, Oluwole S. Aremu, T. Qwebani-Ogunleye, Lebogang Katata-Seru, Zimbili Mkhize, John F. Trant

Chemistry and Biochemistry Publications

Respiratory tract infections arise due to the introduction of microbes into the airway, disrupting the normal, healthy, complex interdependent microbiome. The selective disruption of this community can be either beneficial or dangerous. Nanoparticles are a potential tool for modifying this population. Coated silver nanoparticles (AgNPs) were synthesized using ethanolic extracts of Hypoxis hemerocallidea (EEHH), a Southern African plant used extensively in traditional medicine and the source of many bioactive secondary metabolites. The room temperature reaction between silver nitrate and EEHH forms largely spherical AgNPs with an average diameter of 6–20 nm. These nanoparticles show similar levels of antibacterial activity as …

New Isolate From Salvinia Molesta With Antioxidant And Urease Inhibitory Activity, Nadra Naheed, Saima Maher, Farooq Saleem, Ajmal Khan, Abdul Wadood, Saima Rasheed, M. Iqbal Choudhary, Matheus Froeyen, Iskandar Abdullah, Muhammad Usman Mirza, John F. Trant, Sarfraz Ahmad

Chemistry and Biochemistry Publications

Urease plays a significant role in the pathogenesis of urolithiasis pyelonephritis, urinary catheter encrustation, hepatic coma, hepatic encephalopathy, and peptic acid duodenal ulcers. Salvinia molesta was explored to identify new bioactive compounds with particular emphasis on urease inhibitors. The aqueous methanol extract was fractionated using solvents of increasing polarity. A series of column chromatography and later HPLC were performed on butanol extract. The structures of the resulting pure compounds were resolved using NMR (1D and 2D), infrared, and mass spectroscopy. The novel isolate was evaluated for antioxidant activity (using DPPH, superoxide anion radical scavenging, oxidative burst, and Fe+2 chelation assays), …

Improving E-Commerce Product Recommendation Using Semantic Context And Sequential Historical Purchases, Mahreen Nasir, C. I. Ezeife, Abdulrauf Gidado

Computer Science Publications

Collaborative Filtering (CF)-based recommendation methods suffer from (i) sparsity (have low user–item interactions) and (ii) cold start (an item cannot be recommended if no ratings exist). Systems using clustering and pattern mining (frequent and sequential) with similarity measures between clicks and purchases for next-item recommendation cannot perform well when the matrix is sparse, due to rapid increase in number of items. Additionally, they suffer from: (i) lack of personalization: patterns are not targeted for a specific customer and (ii) lack of semantics among recommended items: they can only recommend items that exist as a result of a matching rule generated …

From Fat To Bilayers: Understanding Where And How Vitamin E Works, Jeffrey Atkinson, Drew Marquardt, Mitchell Dipasquale, Thad Harroun

Chemistry and Biochemistry Publications

Vitamin E was one of the last fat-soluble vitamins to be discovered. We provide here an historical review of the discovery and the increasingly more detailed understanding of the role of α-tocopherol both as an antioxidant and as a structural component of phospholipid bilayer membranes. Despite the detailed descriptions now available of the orientation, location, and dynamics of α-tocopherol in lipid bilayers, there are still gaps in our knowledge of the effect of α-tocopherol and its potential receptors than control gene transcription.

Efficient And Reproducible Synthesis Of An Fmoc-Protected Tn Antigen, Sabrina M. Piazza, Michael R. Reynolds, Jonathan Chiaramonte, Peihan Xu, Fabiola A. Chapa-Villarreal, John F. Trant

Chemistry and Biochemistry Publications

This concise total synthesis of the Thomsen-Nouveau (Tn) glycoconjugate was accomplished using a palladium-catalyzed coupling between the glycosyl donor and Fmoc-protected serine acceptor. This is, to the best of our knowledge, the shortest synthesis reported from galactose for preparing this essential building block for large-scale solid phase peptide synthesis.

A Calorimetric, Volumetric And Combined Sans And Saxs Study Of Hybrid Siloxane Phosphocholine Bilayers, Mark B. Frampton, Doruntina Yakoub, John Katsaras, Paul M. Zelisko, Drew Marquardt

Chemistry and Biochemistry Publications

Siloxanes are molecules used extensively in commercial, industrial, and biomedical applications. The inclusion of short siloxane chains into phospholipids results in interesting physical properties, including the ability to form low polydispersity unilamellar vesicles. As such, hybrid siloxane phosphocholines (SiPCs) have been examined as a potential platform for the delivery of therapeutic agents. Using small angle X-ray and neutron scattering, vibrating tube densitometry, and differential scanning calorimetry, we studied four hybrid SiPCs bilayers. Lipid volume measurements for the different SiPCs compared well with those previously determined for polyunsaturated PCs. Furthermore, the different SiPC's membrane thicknesses increased monotonically with temperature and, for …

Accident Experiences And Reporting Practices In Canadian Chemistry And Biochemistry Labs: A Pilot Investigation, Dana Ménard, John F. Trant

Chemistry and Biochemistry Publications

Accidents in chemistry and biochemistry laboratories are a regular occurrence and have been associated with injuries, property damage, and deaths. However, despite a high prevalence rate of accident involvement reported in previous investigations of academic lab personnel (approximately 30%), little is known about the context in which academic lab accidents occur. Previous findings also suggest a high degree of accident underreporting (25–40%), but again, little is known about this phenomenon. Pilot data was gathered from a convenience sample of 104 students and postdoctoral fellows in chemistry-related fields through an online survey. Results showed a high level of accident involvement (56.7%); …

Fabrication Of An Autonomously Self-Healing Flexible Thin-Film Capacitor By Slot-Die Coating, Susanna Vu, Gnanesh Nagesh, Nastaran Yousefi, John F. Trant, David S.K. Ting, M. Jalal Ahamed, Simon Rondeau-Gagné

Chemistry and Biochemistry Publications

Flexible pressure sensors with self-healing abilities for wearable electronics are being developed, but generally either lack autonomous self-healing properties or require sophisticated material processing methods. To address this challenge, we developed flexible, low-cost and autonomously self-healing capacitive sensors using a crosslinked poly(dimethylsiloxane) through metal-ligand interactions processed into thin films via slot-die coating. These films have excellent self-healing properties, approximately 1.34 × 105 μm3 per hour at room temperature and 2.87 × 105 μm3 per hour at body temperature (37 °C). Similarly, no significant change in capacitance under bending strain was observed on these flexible thin-films when assembled on poly(ethyleneterephthalate) (PET) …

A Network-Based Approach For Computational Drug Repurposing On Cancer Data, Ann Reba, Thomas Alexander

Electronic Theses and Dissertations

In this thesis, we are interested in finding the best drugs that can be repurposed for the disease and able to find the adverse effects such drugs that are FDA-Approved. Developing an effective drug can be a time-consuming and expensive crucible method. Network-based machine learning methods are used for predicting a given drug for A that can be used for B. It aims at finding new indications for already existing drugs and therefore increases the available therapeutic choices at a fraction of the cost of new drug development. The perturbation gene expression data corresponding to the MCF7 cell line was …

Comparative Study Of Reinforcement Learning Methods In Path Planning, Daniel Obawole

Electronic Theses and Dissertations

In order to perform a large variety of tasks and achieve human-level performance in complex real-world environments, an intelligent agent must be able to learn from its dynamically changing environment. Generally speaking, agents have limitations in obtaining an accurate description of the environment from what they perceive because they may not have all the information about the environment. The present research is focused on reinforcement learning algorithms that represent a defined category in the field of machine learning because of their unique approach based on a trial-error basis. Reinforcement learning is used to solve control problems based on received rewards. …

Population Genetic Analyses Of Arctic Char (Salvelinus Alpinus) Life History Types In Nettilling Lake & Amadjuak River Ecosystem: A Test Of Reproductive Isolation, Chen Liu

Electronic Theses and Dissertations

A great number of studies have identified strong genetic differences between sympatric anadromous and resident populations of Salmonidae. However, Arctic char (Salvelinus alpinus) migratory phenotypes in the Nettilling Lake and Amadjuak River ecosystem in Nunavut, Canada have not been genetically characterized, and it remains unclear if distinct genotypes and phenotypes associated with migratory life history differences are maintained through reproductive isolation, and they have been assumed to be sympatric populations, or co-occurring populations. Co-occurring Arctic char (n=225) were sampled from eleven sites along the Amadjuak River in 2014 and 2015. Twelve microsatellite loci were used to quantify genetic variation among …

A Study Of Some Transportation Networks From A Complex Network Perspective Chakrabarthy, Pooja., Pooja Chakrabarthy

Electronic Theses and Dissertations

Complex networks are ubiquitous; consider, for example, road networks, protein-protein interaction networks, metabolic networks, power networks etc. They can be applied to a wide range of areas like mathematics, computer science, social, and biological sciences. Random graphs can aid in observing the topological features in various data sources and give insights on their respective real-world networks. In this thesis, we study the particular case of small-world networks and compare them with random and regular networks. We start by explaining the complexity of networks and how graph theory can be applied to complex networks to understand their topological properties. Using which, …

Neural Network Based Approach For Detecting Location Spoofing In Vehicular Communication, Smarth Kukreja

Electronic Theses and Dissertations

Vehicular Ad hoc Network (VANET) is an evolving subset of MANET. It's deployed on the roads, where vehicles act as mobile nodes. Active security and Intelligent Transportation System (ITS) are integral applications of VANET, which require stable and uninterrupted vehicle-to-vehicle communication technology. VANET, is a type of wireless network, due to which it is quite prone to security attacks. Extremely dynamic connections, sensitive data sharing and time-sensitivity of this network make it a vulnerable to security attacks. The messages shared between the vehicles are the basic safety message (BSM), these messages are broadcasted by each vehicle in the network to …

Cluster Hire In Social Networks Using Modified Weighted Structural Clustering Algorithm For Networks (Mwscan), Harshil Patal

Electronic Theses and Dissertations

The concept of effective collaboration within a group is immensely used in organizations as a viable means for improving team performance. Any organization or prominent institute, who works with multiple projects needs to hire a group of experts who can complete a set of projects. When hiring a group of experts, numerous considerations must be taken into account. In the Cluster Hire problem, we are given a set of experts, each having a set of skills. Also, we are given a set of projects, each requiring a set of skills. Upon completion of each project, a profit is generated for …

Multifaceted Environmental Enrichment In Industrial Fish Hatcheries: The Influence Of Enriched Rearing On The In-Situ Behaviour And Post-Stocking Success Of Juvenile Atlantic Salmon (Salmo Salar), Justine Elizabeth Mcandrews

Electronic Theses and Dissertations

Hatchery fish reared and stocked to sustain or restore wild populations often perform poorly in novel environments compared to their wild counterparts. To combat maladaptive hatchery-acquired traits environmental enrichment is an emerging tool used to provide ‘life skills training’ to hatchery fish prior to release. Through the application of simple yet multifaceted enrichment protocols in an industrial fish hatchery, this thesis aimed to demonstrate how enrichment could be applied to improve the ecological viability of stocked fish. At a provincially-run fish hatchery, a subgroup of juvenile Atlantic salmon (Salmo salar) were subject to 10 weeks of environmental enrichment …

Deep Learning Applications In Medical Bioinformatics, Ziad Omar

Electronic Theses and Dissertations

After a patient’s breast cancer diagnosis, identifying breast cancer lymph node metastases is one of the most important and critical factor that is directly related to the patient’s survival. The traditional way to examine the existence of cancer cells in the breast lymph nodes is through a lymph node procedure, biopsy. The procedure process is time-consuming for the patient and the provider, costly, and lacks accuracy as not every lymph node is examined. The intent of this study is to develop an artificial neural network (ANNs) that would map genetic biomarkers to breast lymph node classes using ANNs. The neural …

A Framework To Study The Impact Of Interventions On Social Isolation During Pandemics Using Multi-Agent Simulation, Simranpreet Kaur

Electronic Theses and Dissertations

The spread of Coronavirus, widely known as COVID-19, has posed detrimental effects worldwide, affecting almost every primary sector. Due to its asymptomatic behavior and non-early diagnosis, government and health organizations implemented interventions such as physical distancing, lockdown, and quarantine, to mitigate the spread of the virus. Studies have shown that a connection exists between social isolation and health risks experienced by individuals. Thus, this research proposes an agent-based model to address the impact of varying interventions in our society. For simulation purposes, the SEIR model is followed, and agents are categorized into two classes based on their pace of movement, …

Assessing The Adaptive Capacity Of An Arctic Seabird To Increasing Frequency In Predation Risk From Polar Bears Using Behavioural And Physiological Metrics, Erica Anne Geldart

Electronic Theses and Dissertations

Predator-prey dynamics in the Arctic are being altered with changing sea-ice phenology. The increasing frequency of predation on colonial nesting seabird eggs by a rare predator - the polar bear (Ursus maritimus), is a consequence of bears shifting to terrestrial food resources through a shortened seal-hunting season. I study a colony of nesting common eiders (Somateria mollissima) on Mitivik (East Bay) Island, Nunavut, Canada, that is exposed to established nest predators such as arctic fox (Vulpes lagopus), but has recently experienced an increase in polar bear nest predation due to the bears’ lost on-ice hunting opportunities. Given eiders’ limited eco-evolutionary …

Computational Enzymology On Sulfur-Containing Enzymes: From Method To Application, Paul Meister

Electronic Theses and Dissertations

Sulfur-containing biomolecules display incredible functional diversity. Indeed, in addition to thiols and thioethers, S-nitrosothiols, 3,4-coordinate, sulfoxides, persulfides and now even polysulfides are commonly observed intermediates. Unfortunately, however, their biological synthesis and roles remain poorly understood. In addition, sulfur-containing species can access a broad range of oxidation states and thus can act as either an electrophile or nucleophile giving rise to an even more diverse set of sulfur-derived functional groups. However, these unique properties can lead to difficulties in characterizing such compounds experimentally and reinforces the need for computational studies to reliably predict their structural and energetic properties. In this dissertation, …

Improved Glove Word Embedding Using Linear Weighting Scheme For Word Similarity Tasks, Qinglan Lu

Electronic Theses and Dissertations

One of the trends in Natural Language Processing (NLP) is the use of word embedding. Its aim is to build a low dimensional vector representation of words from text corpora. Global Vectors for Word Representation (GloVe) and Sikp-Gram with Negative Sampling (SGNS) are two representative word embedding methods. Existing papers have different conclusions on the performance of these two methods. This thesis focuses on GloVe and studies its commonalities and differences with SGNS.

Word co-occurrence is the cornerstone of all word embedding algorithms. One difference between GloVe and SGNS is the definition of co-occurrence. The weight of co-occurring words tapers …

Numerical Modeling Of Controlling Factors For Formation Of Unconformity-Related Uranium Deposits In Sedimentary Basins, Jiayue Shen

Electronic Theses and Dissertations

Unconformity-related uranium (URU) deposits are the most profitable uranium deposits in the world. Among those deposits, the Athabasca Basin hosts the world’s largest high-grade uranium deposits. A series of numerical experiments regarding the effect of uranium source location, fault location, and fault dip angle on the formation of URU deposits have been conducted by using software TOUHREACT.

Simulation results suggest that although both sandstone-sourced and basement-sourced models can generate economical deposits, basement-sourced models are more likely to form larger deposits since uranium-carrying fluid only needs to move a shorter distance to reach the structural trap for further ore forming reaction. …

Physiological State Determinants Of Maternal Cortisol Signaling And Its Impact On Offspring Quality And Fitness, Sydney Currier

Electronic Theses and Dissertations

Assessing the intergenerational effects of maternal stress is important for predicting how offspring will respond to changing environments. The overall aim of my thesis was to quantify the effects of maternal state on maternally derived egg cortisol and determine whether this variation in egg cortisol impacts Chinook salmon offspring performance and fitness in a sex-specific way. I quantified within-female changes in maternal energetics and reproductive metrics that I linked to egg quality and ultimately embryo survival. I found egg cortisol increases with increasing maternal plasma cortisol, and increases further as plasma cortisol levels rise with each day that eggs are …

Variational Energies For The Rydberg P States Of Helium, Cody Mcleod

Electronic Theses and Dissertations

The aim of this work is to solve the quantum mechanical three-body problem for helium, and to obtain high precision eigenvalues for the higher-lying Rydberg states where previous methods have been of limited accuracy. A variational method in correlated Hylleraas coordinates is used involving three distinct distance scales, called a triple basis set. The eigenvalues and matrix elements of other operators are computed for P states of helium up to n = 15 using the varational method with a triple basis set in Hylleraas coordinates. The construction of the wave functions, as well as the behaviour of the asymptotic, intermediate …

Packing Non-Self-Crossing Edge-Disjoint Spanning Paths Into A Point Set, Rishav Chatterjee

Electronic Theses and Dissertations

The term packing refers to the arrangement of multiple geometrical structures or shapes such as circles, squares, triangles, or polygons into a fixed and finite set of points. The geometric structures to be packed can also be trees and paths. Packing is also possible in a 3-dimensional space with geometric structures such as spheres, cylinders, and cubes.

The concept of packing was introduced more than half a century ago. Since then, many researchers have studied the packing strategies of different geometric structures in different configurations of point-set. Packing strategies help to construct and arrange multiple geometric structures in a predetermined …

Traffic Sign And Light Detection Using Deep Learning For Automotive Applications, Humaira Naimi

Electronic Theses and Dissertations

Traffic sign and light detection are core components of Advanced Driver Assistance Systems (ADAS) and self-driving vehicles. The automotive industry is widely employing numerous approaches for automation through computer vision techniques. Object detection algorithms based on deep learning can be divided into two main categories, two stage and single stage detection algorithms. Two stage algorithms are designed to improve detection accuracy. While single stage algorithms are constructed to be faster, this increases their suitability for real time applications. This thesis presents a lightweight traffic sign and light detector by adapting a single stage, Single Shot Multibox Detection (SSD) algorithm by …

Emergency Evaluation In Connected And Automated Vehicles, Elvin Eziama

Electronic Theses and Dissertations

An intelligent transportation system (ITS) provides improved transport efficiency and safety based on vehicle communication. Connected and automated vehicles (CAVs) as part of an ITS are projected to revolutionize the transportation industry, primarily by allowing real-time and seamless information exchange between vehicles and roadside infrastructure. Although these CAVs are expected to offer vast benefits, new problems in terms of safety, security, and privacy will also emerge. Since CAVs continue to rely heavily on vehicle sensors and information obtained from other vehicles and roadside units, abnormal sensors and malicious cyber attacks can lead to destructive results and fatal crashes. Therefore, ensuring …

Gamification Platform For Social Engineering Training And Awareness, Rui Xu

Electronic Theses and Dissertations

Almost every type of cybersecurity incident leverages one or more social engineering attacks. Nowadays social engineering attack is considered one of the most significant threats to individuals and organizations. It is an attacking technique that manipulates and deceives users to access or gain privileged information. Cybersecurity training is an effective defense method to enhance people's awareness of social engineering attacks, especially training through game playing or educational games. However, fewer tools can customize social engineering simulations based on user's characteristics and needs. Some social engineering training tools are lack motivation, engagement, and interaction.

Gamification is the use of game elements …