Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 30871 - 30900 of 302581

Full-Text Articles in Physical Sciences and Mathematics

Noise Pollution And Its Effects On Human Mental And Physical Health, Seth Anderson May 2022

Noise Pollution And Its Effects On Human Mental And Physical Health, Seth Anderson

Department of Environmental Studies: Undergraduate Student Theses

Noise pollution is defined as unwanted sound, capable of causing both mental and physical harm. In order to see if there was a correlation between increasing noise pollution (dB) and (a) increasing Negative Affect Score (NAS), (b) decreasing Positive Affect Score (PAS), and (c) increasing Resting Heart Rate (RHR), research was conducted. Participants were taken to four different testing locations, each with a corresponding dB level, and asked to (a) have their Resting Heart Rate (RHR) taken and (b) fill out a questionnaire based on the Positive and Negative Affect Schedule (PANAS) psychological measure. At the conclusion of this study, …


The Effects Of Human Activity On Reintroduced Bighorn Sheep (Ovis Canadensis) Populations, Justine Cherovsky May 2022

The Effects Of Human Activity On Reintroduced Bighorn Sheep (Ovis Canadensis) Populations, Justine Cherovsky

Department of Environmental Studies: Undergraduate Student Theses

Since the decimation of North America’s bighorn sheep (Ovis canadensis) populations due to human impacts, translocations have been the primary conservation strategy to repopulate the native habitat. Following the extirpation of the species in Nebraska, bighorns were reintroduced with the hope to establish a stable population, but nearly four decades of management has resulted in large-scale die-offs and unstable herds. Ongoing human impacts have created similar results across the country as reintroductions struggle to establish independent bighorn herds. A systematic literature review was conducted to analyze current human related effects, evaluate the effectiveness of management practices, and compare these findings …


How Can Stakeholders In Food Sovereignty Achieve More Political Power?, Micah Dierks May 2022

How Can Stakeholders In Food Sovereignty Achieve More Political Power?, Micah Dierks

Department of Environmental Studies: Undergraduate Student Theses

Food sovereignty (FSv) is a peasant-driven, transnational movement that emerged in response to land-grabbing and the consolidation of power in food production. It advocates for the rights of people to define their own food practices and systems. To provide targeted feedback for movement reflexivity, 21 ecological conflicts referencing food sovereignty were sampled from the Global Atlas of Environmental Justice (the EJAtlas). Involved groups of actors and their forms of mobilization were correlated with interpretations of success from the EJAtlas. I recommend that stakeholders in food sovereignty pursue the acquisition of greater political power through improving messaging, leveraging or disrupting existing …


Supercritical Water Gasification And Pyrolysis – Cleaning Up The Great Pacific Garbage Patch, Kelly L. Emery May 2022

Supercritical Water Gasification And Pyrolysis – Cleaning Up The Great Pacific Garbage Patch, Kelly L. Emery

Department of Environmental Studies: Undergraduate Student Theses

This research paper is a comparative meta-analysis of gasification of hydrocarbons in supercritical water, specifically concerning the great pacific garbage patch (GPGP). The research explores two ways to clean up the GPGP while also harnessing the waste as biofuel. This research compares the environmental and economic outcomes between supercritical water gasification and pyrolysis. I will be comparing which thermochemical process of converting hydro-pollution into usable, methane-rich gas is most economically beneficial and environmentally sustainable. The relevance of this use of plastic refuse is that it would not just be diverted to a different landfill or back right where it started …


The Accessibility And Sustainability Of Local Foods: A Snapshot From The Food Hubs Of Lincoln, Nebraska, Tess Foxall May 2022

The Accessibility And Sustainability Of Local Foods: A Snapshot From The Food Hubs Of Lincoln, Nebraska, Tess Foxall

Department of Environmental Studies: Undergraduate Student Theses

The current state of agriculture in the United States utilizes industrial practices that pose a myriad of risks to both human and environmental health. By focusing on smaller farms and local food systems that utilize more sustainable agriculture practices, communities can benefit in terms of economic, environmental, and social health. Food hubs can play a key role in local food systems to connect local producers with consumers and increase access to local food. The goal of the research was to analyze the accessibility and sustainability of local food from food hubs in Lincoln, Nebraska to find the key barriers to …


Apparent Temperature & Relative Humidity In Nebraska: A Comparative Analysis On Wet Bulb Globe Temperature (Wbgt) Tools, Rachel T. Hines May 2022

Apparent Temperature & Relative Humidity In Nebraska: A Comparative Analysis On Wet Bulb Globe Temperature (Wbgt) Tools, Rachel T. Hines

Department of Environmental Studies: Undergraduate Student Theses

Heat waves can lead to illness and death, particularly among older adults, the very young, and other vulnerable populations. More frequent severe heat waves are expected to impact Nebraska. Looking specifically into Lincoln, NE for future climate trends, over the next 100 years, “the number of hot days would increase by 13-22 days during a given summer (depending upon the scenario), and the number of warm nights would increase by 20-35 nights each summer” Bathke et al. (2014). These higher summer temperatures will “increase electricity use, causing higher summer peak loads” as well as “pose physical and mental health challenges…outdoor …


E-Waste Impact On The Health Of Guiyu, China Citizens: A Comparison Pre And Post China’S Prohibition Of Foreign Garbage Imports, Oliva Hultman May 2022

E-Waste Impact On The Health Of Guiyu, China Citizens: A Comparison Pre And Post China’S Prohibition Of Foreign Garbage Imports, Oliva Hultman

Department of Environmental Studies: Undergraduate Student Theses

Electronic Waste (E-waste) is an inevitable product in our society. At the end of a technological products lifespan, this waste is commonly exported from the Western World to places like Guiyu, China. There the waste has been recycled by melting and dissection of devices. However, these devices contain harmful materials like Lead (Pb) and other heavy metals. These components of the technology process, when not properly dealt with, leach into the citizens’ lives. In 2017, China issued a Prohibition on Foreign Garbage Imports where, while focusing on plastics, limited the waste being brought into the country. This study will compare …


Simulating The Common Envelope Phase Using Moving-Mesh Hydrodynamics, Logan James Prust May 2022

Simulating The Common Envelope Phase Using Moving-Mesh Hydrodynamics, Logan James Prust

Theses and Dissertations

Common envelope evolution (CEE) is a phase in the evolution of a binary system where a giant star and a smaller companion share a gaseous envelope, and is responsible for the formation of many systems of astrophysical interest. Despite its importance, CEE is not well understood due to the diverse physics involved. Astronomers have roughly modeled CEE using conserved quantities such as energy, but progress has been limited by uncertainties in the contributions of various energy sources. Thus, 3-D numerical simulations must be brought to bear. Here two methodologies are commonly employed, each of which comes with its own set …


Investigation Into The Measurement Of Student Ability: Refinements, Improvements And Enhanced Understanding Of Factors That Influence Performance, David Schreurs May 2022

Investigation Into The Measurement Of Student Ability: Refinements, Improvements And Enhanced Understanding Of Factors That Influence Performance, David Schreurs

Theses and Dissertations

The following series of experiments were all designed and implemented with the goal of understanding and improving undergraduate students understanding of chemistry. In order to accurately access changes in student’s chemistry understanding, the first chapter focuses on how a student’s chemistry proficiency can be most effectively measured. This includes practical recommendations for the average instructor as well as advanced methods more appropriate for researchers who require highly precise scores. With a better understanding on how to measure student proficiency, the next step was working to improve student understanding through various types of feedback following assessments. On top of establishing a …


Evaluation Of Social Bot Detection Models, Muhammet Buğra Torusdağ, Mücahi̇d Kutlu, Ali̇ Aydin Selçuk May 2022

Evaluation Of Social Bot Detection Models, Muhammet Buğra Torusdağ, Mücahi̇d Kutlu, Ali̇ Aydin Selçuk

Turkish Journal of Electrical Engineering and Computer Sciences

Social bots are employed to automatically perform online social network activities; thereby, they can also be utilized in spreading misinformation and malware. Therefore, many researchers have focused on the automatic detection of social bots to reduce their negative impact on society. However, it is challenging to evaluate and compare existing studies due to difficulties and limitations in sharing datasets and models. In this study, we conduct a comparative study and evaluate four different bot detection systems in various settings using 20 different public datasets. We show that high-quality datasets covering various social bots are critical for a reliable evaluation of …


An Evaluation Of Security In Blockchain-Based Sharing Of Student Records In Higher Education, Timothy Arndt, Angela Guercio, Yonghun Chae May 2022

An Evaluation Of Security In Blockchain-Based Sharing Of Student Records In Higher Education, Timothy Arndt, Angela Guercio, Yonghun Chae

Information Systems

Blockchain has recently taken off as a disruptive technology, from its initial use in cryptocurrencies to wider applications in areas such as property registration and insurance due to its characteristic as a distributed ledger which can remove the need for a trusted third party to facilitate transactions. This spread of the technology to new application areas has been driven by the development of smart contracts – blockchain-based protocols which can automatically enforce a contract by executing code based on the logic expressed in the contract. One exciting area for blockchain is higher education. Students in higher education are ever more …


A Comprehensive Bison Management And Research Plan For The Crane Trust, Joshua D. Wiese May 2022

A Comprehensive Bison Management And Research Plan For The Crane Trust, Joshua D. Wiese

Other Publications in Wildlife Management

The Great Plains were once a vast grassland ecosystem, but, due to agricultural and human development, are one of the most endangered ecosystems in North America. What remains is generally fragmented, threatened by invasive species, and lacks the natural ecosystem processes that shaped these grasslands such as periodic wildfire and bison grazing. Since 1978, the Platte River Whooping Crane Maintenance Trust, Inc. (dba “Crane Trust”) has worked to maintain the function of grassland and riparian habitats to benefit endangered Whooping Cranes, Sandhill Cranes, and other migratory bird species. They protect ~8,100 acres, including the largest contiguous portion of lowland tallgrass …


An Afm Approach Applied In A Study Of Α-Crystallin Membrane Association: New Insights Into Lens Hardening And Presbyopia Development, Nawal K. Khadka, Raju Timsina, Laxman Mainali May 2022

An Afm Approach Applied In A Study Of Α-Crystallin Membrane Association: New Insights Into Lens Hardening And Presbyopia Development, Nawal K. Khadka, Raju Timsina, Laxman Mainali

Physics Faculty Publications and Presentations

The lens of the eye loses elasticity with age, while α-crystallin association with the lens membrane increases with age. It is unclear whether there is any correlation between α-crystallin association with the lens membrane and loss in lens elasticity. This research investigated α-crystallin membrane association using atomic force microscopy (AFM) for the first time to study topographical images and mechanical properties (breakthrough force and membrane area compressibility modulus (KA), as measures of elasticity) of the membrane. α-Crystallin extracted from the bovine lens cortex was incubated with a supported lipid membrane (SLM) prepared on a flat mica surface. The …


Mapping Salt-Affected Land In The South-West Of Western Australia Using Satellite Remote Sensing, P A. Caccetta, John A. Simons, S Furby, Nicholas J. Wright, Richard J. George Dr May 2022

Mapping Salt-Affected Land In The South-West Of Western Australia Using Satellite Remote Sensing, P A. Caccetta, John A. Simons, S Furby, Nicholas J. Wright, Richard J. George Dr

Natural resources published reports

Dryland salinity is a pervasive form of land degradation that has resulted from the clearing of about 17 M ha of native vegetation and the introduction of predominately cereal and pasture-based farming systems in the South-West of Western Australia. The change in water balance caused by clearing deep rooted endemic woodlands increased recharge and resulted in rising groundwater levels. After a lag period, the regolith began filling and groundwater approached the soil surface, evaporating and depositing stored salts in the rootzone of salt sensitive crops. Groundwater levels also rise and affect areas of remnant native vegetation, streams, wet-lands and rural …


Practitioners' Expectations On Automated Code Comment Generation, Xing Hu, Xin Xia, David Lo, Zhiyuan Wan, Qiuyuan Chen, Thomas Zimmermann May 2022

Practitioners' Expectations On Automated Code Comment Generation, Xing Hu, Xin Xia, David Lo, Zhiyuan Wan, Qiuyuan Chen, Thomas Zimmermann

Research Collection School Of Computing and Information Systems

Good comments are invaluable assets to software projects, as they help developers understand and maintain projects. However, due to some poor commenting practices, comments are often missing or inconsistent with the source code. Software engineering practitioners often spend a significant amount of time and effort reading and understanding programs without or with poor comments. To counter this, researchers have proposed various techniques to automatically generate code comments in recent years, which can not only save developers time writing comments but also help them better understand existing software projects. However, it is unclear whether these techniques can alleviate comment issues and …


Removal Of Arsenic (Iii) And Arsenic (V) From Aqueous Solution Via Common Sunflower Helianthus Annuus By Phytoremediation, Irving A. Vazquez Hurtado May 2022

Removal Of Arsenic (Iii) And Arsenic (V) From Aqueous Solution Via Common Sunflower Helianthus Annuus By Phytoremediation, Irving A. Vazquez Hurtado

Theses and Dissertations

Phytoremediation provides a cost-effective, non-invasive technique to remove contaminants from the soil and groundwater. Sunflowers are fast growing and have a showed effective at removing various pollutants from soil, including lead and other heavy metals. Health issues related to arsenic are mainly attributed to exposure of arsenite, whereas arsenate is much less toxic. The common sunflower Helianthus annuus was the species used to remove both arsenic (III) and As(V) ions from hydroponics solutions. In the present study sunflower seeds were germinated for a week, placed under the sun for a day and subsequently placed in a nutrient solution to aid …


Verification In Generalizations Of The 2-Handed Assembly Model, David Caballero May 2022

Verification In Generalizations Of The 2-Handed Assembly Model, David Caballero

Theses and Dissertations

Algorithmic Self Assembly is a well studied field in theoretical computer science motivated by the analogous real world phenomenon of DNA self assembly, as well as the emergence of nanoscale technology. Abstract mathematical models of self assembly such as the Two Handed Assembly model (2HAM) allow us to formally study the computational capabilities of self assembly. The 2HAM is one of the most thoroughly studied models of self assembly, and thus in this paper we study generalizations of this model. The Staged Tile Assembly model captures the behavior of being able to separate assembly processes and …


Computational Complexity In Tile Self-Assembly, Timothy Gomez May 2022

Computational Complexity In Tile Self-Assembly, Timothy Gomez

Theses and Dissertations

One of the most fundamental and well-studied problems in Tile Self-Assembly is the Unique Assembly Verification (UAV) problem. This algorithmic problem asks whether a given tile system uniquely assembles a specific assembly. The complexity of this problem in the 2-Handed Assembly Model (2HAM) at a constant temperature is a long-standing open problem since the model was introduced. Previously, only membership in the class coNP was known and that the problem is in P if the temperature is one (τ = 1). The problem is known to be hard for many generalizations of the model, such as allowing one …


Engaging Students During Research Through The Use Of Games, Francisco Gonzalez May 2022

Engaging Students During Research Through The Use Of Games, Francisco Gonzalez

Theses and Dissertations

Engaging students during a research seminar/meeting can be a difficult challenge, and as as student myself, I can attest to how difficult actively listening to a presentation can be. As such, upon researching more ways to have an audience engaged, one of the most promising concepts is the use of games. Games, in any form, can be very engaging to a person, and even more so if there is active engagement and participation within an audience group. With this concept in mind, I decided to take it upon myself to create a game based around a theoretical computer …


Pentagonal Tilings Of The Plane, Ariana T. Hinojosa May 2022

Pentagonal Tilings Of The Plane, Ariana T. Hinojosa

Theses and Dissertations

Tilings are mathematical objects that allow us to use geometry to visualize interaction between objects as well as to create artistic realization of mathematical objects in the plane and in the space.

We will focus on tilings of the plane that use only one type of convex pentagonal tile each, the pentagonal tilings. There are fifteen types of pentagonal tiles, with each containing their own set of restrictions. The main result of this thesis is an interactive realization of all fifteen types of pentagonal tiles using GeoGebra.


Total Synthesis Of Mansouramycin A, Abigail M. Zepeda May 2022

Total Synthesis Of Mansouramycin A, Abigail M. Zepeda

Theses and Dissertations

In 2009 bioactive compounds from marine Streptomyces species was isolated which resulted in deriving four isoquinoline-quinone alkaloids known as Mansouramycins A-D. There have been reports that there are 36 non-small cancer cells against cytotoxicity in Mansouramycins A-C in lung cancer, breast cancer, melanoma, and prostate cancer cells. Reports that have conducted total syntheses were all specific to a single compound only Mansouramycin A and D. However, in precedent methods, to obtain the derivatives with different substituents are limited when the substituents are on the fused-pyridine ring. Thus, a develop a systematic synthetic methods of isoquinoline-quinones, which are to be able …


Investigation Of A Simultaneaous Direct And Indirect Contact Dehumidifier Using Parallel Strings For Hdh Desalination, Josue Perez Perez May 2022

Investigation Of A Simultaneaous Direct And Indirect Contact Dehumidifier Using Parallel Strings For Hdh Desalination, Josue Perez Perez

Theses and Dissertations

Freshwater is a limited and precious resource. Currently, half a billion people in the world face sever water scarcity all year round. Humidification dehumidification (HDH) systems have received special attention among the variety of small-scale desalination technologies due to its potential to create affordable and sustainable seawater desalination, especially when combined with natural power sources such as waves, wind, and solar rays. Improvements in the development of HDH desalination systems have been achieved in recent years. Nonetheless, the improvements that have received most attention focus on solar heaters and humidifiers. Dehumidification systems have often been adapted from air conditioning condensation …


On Approximating Solitary Wave Solutions For The Classical Euler Equations, Julio C. Paez May 2022

On Approximating Solitary Wave Solutions For The Classical Euler Equations, Julio C. Paez

Theses and Dissertations

In this paper, we use a method based on Hirota substitution or the Wronskian method to find approximate solitary wave solutions to the classical Euler equations. This method uses a small parameter lambda as the basis of approximation, a parameter derived from the form of prospective solutions we consider, rather than the standard small parameters alpha and beta. The L-infinity norm and asymptotic notation are used to measure the accuracy of the approximation rather than finding the error explicitly.


Water Quality Monitoring To Assess Pollutant Loadings In Brownsville Ship Channel Watershed, Ivan Rene Santos Chavez May 2022

Water Quality Monitoring To Assess Pollutant Loadings In Brownsville Ship Channel Watershed, Ivan Rene Santos Chavez

Theses and Dissertations

The Brownsville Ship Channel (BSC) was listed as an impaired waterway from 2010 to 2018 due to screening levels of bacteria concentration. This study aims to address water quality at the three main tributary ditches draining into Brownsville Ship Channel to model present along with future pollutant loads within Brownsville Ship Channel Watershed. Load Duration Curves (LDCs) and Spatial Explicit Load Enrichment Calculation Tool (SELECT) models were developed to determine if current pollutant loads meet water quality standards stablished by the Texas Commission on Environmental Quality (TCEQ), and to estimate average daily potential E. Coli loading contribution from sub-watersheds within …


An Application Of Matrices To The Spread Of The Covid 19, Selena Suarez May 2022

An Application Of Matrices To The Spread Of The Covid 19, Selena Suarez

Theses and Dissertations

We represented a restaurant seating arrangement using matrices by using 0 entry for someone without covid and 1 entry for someone with covid. Using the matrices we found the best seating arrangements to lessen the spread of covid. We also investigated if there was a factor needed to create a formula that could calculate the matrix that shows who would be affected with covid with each seating arrangement. However, there did not seem to be a clear pattern within the factors. Aside from covid applications, we also investigated the symmetries in seating arrangements and the possible combinations with these arrangements …


Synthesis Of Gpr119 Interacting Drugs For Treatment Of Type Ii Diabetes, Tien M. Tran May 2022

Synthesis Of Gpr119 Interacting Drugs For Treatment Of Type Ii Diabetes, Tien M. Tran

Theses and Dissertations

Type II Diabetes is one of the leading causes of death in the United States and is categorized by high blood glucose levels, insulin deficiencies, and inhibition. Located in the pancreas and intestine, the G-Protein Receptor 119 (GPR119) was noted to have an important effect on insulin secretion. Previous studies found that when the receptor is activated, insulin secretion was upregulated which is vital for type II diabetes treatment. Compounds AR437735 and AR437948 are the proposed agonist and inverse agonist pair that will be synthesized and tested for bioactivity to the receptor. It is theorized that the different double-bonded atoms …


A Computer Programming Intervention For Second Grade Math Students, Eric B. Bagley May 2022

A Computer Programming Intervention For Second Grade Math Students, Eric B. Bagley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The multiplication algorithms taught to elementary students are made to help students find answers quickly, but why the algorithm works and how it relates to multiplication is not widely known. For example, one intuitive meaning of multiplication is that of iterated, or, repeated, addition. In this paper, we look at the ways a visual, block-based, programming activity uses the concept of iteration to help second-graders learn multiplication. The results of the study observing second-grade students use visual programming and iteration to setup and solve multiplication story problems. We found that generally students enjoyed these activities and found them helpful during …


The Influence Of A Course On Assessment For Inservice Secondary Mathematics Teachers, Natalie M. Anderson May 2022

The Influence Of A Course On Assessment For Inservice Secondary Mathematics Teachers, Natalie M. Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many mathematics teachers are not prepared to design valid and usable measurements of their students’ mathematical achievements. There are relatively few opportunities for mathematics teachers to improve their assessment literacy. The purpose of this study is to (1) design a course on assessment for inservice mathematics teachers and (2) evaluate the effectiveness of the course. This paper recounts the development of the course and its influence on 16 teachers. Teachers who completed the course submitted a unit outline with learning objectives, a test blueprint, and a unit test. These artifacts influenced my evaluation on the effectiveness of the course. All …


Shallow Composition And Structure Of The San Gabriel Fault, California In Drill Core And Geophysical Logs: Implications For Fault Slip And Energetics, Kaitlyn A. Crouch May 2022

Shallow Composition And Structure Of The San Gabriel Fault, California In Drill Core And Geophysical Logs: Implications For Fault Slip And Energetics, Kaitlyn A. Crouch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Earthquakes are the sudden and intensive release of energy due to slip along faults. This energy may be felt on the Earth’s surface and may cause displacement of the Earth’s crust (seismic slip). As an earthquake ruptures, rocks in and around the fault are damaged and altered. When a fault displaces without earthquakes, it is referred to as aseismic creep. Faults may experience both seismic slip and aseismic creep throughout their cycles. In order to better model earthquake hazards and understand the cause of seismic slip versus aseismic creep in the shallow crust, we need to characterize the properties of …


Fitting Physical Models To Spatiotemporal Observations: Discovering Developmental Regulatory Networks Of Drosophila, Dj Holt May 2022

Fitting Physical Models To Spatiotemporal Observations: Discovering Developmental Regulatory Networks Of Drosophila, Dj Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Deep learning continues to solve significant scientific and engineering problems, but the solutions found are neural networks with thousands of parameters that provide no scientific or engineering insights. A solution to this problem, explored in this work, is to learn mathematical models that represent mechanisms that can be interpreted by scientists and engineers.

A challenging learning problem is to discover the genetic regulatory mechanisms that drive pattern formation during early biological development. Using known mathematical models of these processes, consisting of coupled ordinary differential and partial differential equations, we aim to identify the model parameters that describe the biological mechanisms …