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Full-Text Articles in Physical Sciences and Mathematics

Botdr-Based Horizontal Deformation Monitoring Of Section Coal Pillars, Chai Jing, Hao Hongru, Yang Jianfeng, Gao Dengyan, Gao Kuiying, Chen Jianhua, Yang Lei, Liu Zeyu May 2024

Botdr-Based Horizontal Deformation Monitoring Of Section Coal Pillars, Chai Jing, Hao Hongru, Yang Jianfeng, Gao Dengyan, Gao Kuiying, Chen Jianhua, Yang Lei, Liu Zeyu

Coal Geology & Exploration

To address potential safety hazards like microcrack initiation, deformation, and failure inside coal pillars, this study monitored the horizontal deformations of coal pillars using the Brillouin optical time-domain reflectometry (BOTDR)—a distributed optical fiber sensing technology. Firstly, this study established a method for converting the axial strain of optical fibers into horizontal deformations based on a theoretical analysis of the failure and bulking characteristics of coal pillars. Secondly, it determined the axial tensile response of metal-based cord-shaped sensing optical fibers by conducting laboratory tests. Then, it corrected the strain coefficient based on the deformation and failure patterns of coal pillars. Finally, …

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Geochemical Characteristics And Influencing Factors Of Deep Coalbed Methane In The Linxing-Shenfu Block, Wu Peng, Hu Weiqiang, Li Yangbing, Ma Litao, Li Yong, Zhao Fei, Niu Yanwei, Chen Jianqi, Li Panpan, Liu Zaizhen, Li Chenchen, Cao Di, Liu Cheng May 2024

Geochemical Characteristics And Influencing Factors Of Deep Coalbed Methane In The Linxing-Shenfu Block, Wu Peng, Hu Weiqiang, Li Yangbing, Ma Litao, Li Yong, Zhao Fei, Niu Yanwei, Chen Jianqi, Li Panpan, Liu Zaizhen, Li Chenchen, Cao Di, Liu Cheng

Coal Geology & Exploration

Identifying the origin and geochemical characteristics of deep coalbed methane (CBM) is critical for its exploration and production. This study examined the desorbed gas from deep-CBM parameter wells in the Linxing-Shenfu block on the eastern margin of the Ordos Basin. It systematically tested the composition, content, and carbon isotopes of CBM in coal seams Nos. 8 and 9. In combination with the degree of thermal evolution, gas-bearing properties, coal seam burial depths, geological structures, and hydrogeologic conditions, it delved into the geochemical characteristics and influencing factors of deep CBM. The results show that the deep CBM in the study area …

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Dynamic Simulations And Applicability Evaluation Of Novel Perforation Techniques, Bi Gang, Yuan Peijie, Han Fei, Fu Shuaishuai, Wu Jiemin, Ma Ying May 2024

Dynamic Simulations And Applicability Evaluation Of Novel Perforation Techniques, Bi Gang, Yuan Peijie, Han Fei, Fu Shuaishuai, Wu Jiemin, Ma Ying

Coal Geology & Exploration

The development and improvement of perforated completion techniques hold great practical significance and value for efficient testing and exploitation of oil and gas fields. However, conventional shaped-charge perforation for well completion of low-permeability reservoirs (e.g., low-permeability coal seams) suffered high seepage resistance and reduced productivity due to the presence of compaction damage zones. To achieve enhanced exploitation efficiency of low-permeability reservoirs, novel perforation techniques, including self-cleaning and after-effect perforation, have been proposed. However, their perforation performance and applicability remain ambiguous. Based on the explicit time integration algorithm and fluid-structure interaction mechanism of LS-DYNA, this study proposed a method for finite …

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Anti-Channeling Methods For Coalbed Methane Production Using L-Type Horizontal Wells, Liu Zhan, Zhang Qunxia, Geng Yuxin, Luo Dan, Wang Minggang May 2024

Anti-Channeling Methods For Coalbed Methane Production Using L-Type Horizontal Wells, Liu Zhan, Zhang Qunxia, Geng Yuxin, Luo Dan, Wang Minggang

Coal Geology & Exploration

Coalbed methane (CBM) production using L-type horizontal wells can yield stable single-well production of up to above 8 000 m3/d. However, due to the lack of sand settling pockets, L-type horizontal wells fail to achieve gas-water separation under the action of gravity. Consequently, gas channeling from tubing is prone to occur, significantly decreasing pumping efficiency and restricting further drainage and pressure reduction. By optimizing the lifting process for production in the early stage, the gas channeling from tubing has been somewhat alleviated. However, the anti-channeling effects remain unsatisfactory in low-fluid-pressure and high-yield gas wells. This study examined L-type …

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Technologies For Water Hazard Prevention And Control In Burnt Rock Aquifers Within Concealed Burnt Areas, Wang Hai May 2024

Technologies For Water Hazard Prevention And Control In Burnt Rock Aquifers Within Concealed Burnt Areas, Wang Hai

Coal Geology & Exploration

Burnt rocks are extensively distributed in northwestern China, featuring well-developed pores and fractures and abundant water, emerging as primary aquifers in this region. The burnt rocks in concealed burnt areas in this region show inconspicuous surface remains, complicating their identification. Penetrating burnt rock aquifers in coal mining will lead to water hazard and destroy water resources in these aquifers. To prevent and control water hazard in burnt rocks within concealed burnt areas and preserve water resources in burnt rock aquifers, this study analyzed the distributions of burnt rocks in China and the effects of water in them on coal mining. …

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Exploring A Fly Ash-Based Grouting Material For Toughening Through In Situ Polymerization Of Acrylamide, Zhang Yuehong, Wang Xiaodong, Wang Hai, Wu Boqiang, Ji Zhongkui, Zhu Shibin, Han Le, Feng Longfei May 2024

Exploring A Fly Ash-Based Grouting Material For Toughening Through In Situ Polymerization Of Acrylamide, Zhang Yuehong, Wang Xiaodong, Wang Hai, Wu Boqiang, Ji Zhongkui, Zhu Shibin, Han Le, Feng Longfei

Coal Geology & Exploration

Efficiently controlling the water inflow (loss) of burnt rocks in the roof of coal mining faces requires grouting reinforcement materials with excellent compressive toughness. Silicate cement-based grouting materials, characterized by low costs, have been extensively applied to grouting reinforcement in coal mines. However, their hardened grout is susceptible to deformation, exhibiting poor toughness. By employing the in-situ polymerization of acrylamide (AM) for toughening, this study investigated the effects of AM, cross-linking agent, initiator, and water-cement ratio on the setting time, swelling capacity, compressive strength, and toughness index of the fly ash-based grouting materials. Furthermore, the microstructures of the hardened grout …

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Some Reflections On The Application Of Machine Learning To Research Into The Theoretical System Of Mine Water Prevention And Control, Yao Hui, Yin Huichao, Liang Manyu, Yin Shangxian, Hou Enke, Lian Huiqing, Xia Xiangxue, Zhang Jinfu, Wu Chuanshi May 2024

Some Reflections On The Application Of Machine Learning To Research Into The Theoretical System Of Mine Water Prevention And Control, Yao Hui, Yin Huichao, Liang Manyu, Yin Shangxian, Hou Enke, Lian Huiqing, Xia Xiangxue, Zhang Jinfu, Wu Chuanshi

Coal Geology & Exploration

The theoretical system of mine water prevention and control encompasses three fundamental aspects: disaster-causing mechanisms, risk evaluation, and disaster prediction. This theoretical system, having undergone rapid development over the past 20 years, aims to gain insights into the behavior characteristics of mine water and predict its evolutionary trend, thus serving the prevention and control of water disasters in mining areas. Applying machine learning, a powerful tool for data analysis and mining in the era of big data, to research into the theoretical system has garnered considerable attention. This study focuses on the specific applications of machine learning to the three …

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Debris Fan Produced By Failure Of Canyon-Blocking Pyroclastic Flows, Michael L. Cummings May 2024

Debris Fan Produced By Failure Of Canyon-Blocking Pyroclastic Flows, Michael L. Cummings

Geology Faculty Publications and Presentations

Ash-rich pyroclastic flows from the cataclysmic eruption of Mount Mazama (~7700 yr. B. P.), Cascade volcanic arc, Oregon, entered and blocked the narrow, bedrock-lined canyon of the Williamson River approximately 35 to 44 km from the source volcano. The blockage impounded a body of water which then released producing four stratigraphic units in the downstream debris fan. The four stratigraphic units are a boulder core comprised of locally sourced bedrock boulders and three sand-rich units including a fine-grained sand unit, a sandy pumice gravel (±basalt/hydrovolcanic tuff) unit, and a pumice pebble-bearing, crystal-rich sand unit. Hand-drilled auger holes up to ~1.6 …

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Context Aware Music Recommendation And Playlist Generation, Elias Mann May 2024

Context Aware Music Recommendation And Playlist Generation, Elias Mann

SMU Journal of Undergraduate Research

There are many reasons people listen to music, and the type of music is largely determined by what the listener may be doing while they listen. For example, one may listen to one type of music while commuting, another while exercising, and yet another while relaxing. Without access to the physiological state of the user, current music recommendation methods rely on collaborative filtering - recommending music based on what other similar users listen to - and content based filtering - recommending songs based on their similarities to songs the user already prefers. With the rise in popularity of smart devices …

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A Review Of The Toxicity Of Ingredients In E-Cigarettes, Including Those Ingredients Having The Fda's "Generally Recognized As Safe (Gras)" Regulatory Status For Use In Food., Nada O F Kassem, Robert M. Strongin, Andrea M. Stroup, Marielle C. Brinkman, Ahmad El-Hellani, Hanno C. Erythropel, Arash Etemadi, Vernat Exil, Maciej L. Goniewicz, Noura O. Kassem, Theodore P. Klupinski, Sandy Liles, Thivanka Muthumalage, Alexandra Noël, David H. Peyton, Qixin Wang, Multiple Additional Authors May 2024

A Review Of The Toxicity Of Ingredients In E-Cigarettes, Including Those Ingredients Having The Fda's "Generally Recognized As Safe (Gras)" Regulatory Status For Use In Food., Nada O F Kassem, Robert M. Strongin, Andrea M. Stroup, Marielle C. Brinkman, Ahmad El-Hellani, Hanno C. Erythropel, Arash Etemadi, Vernat Exil, Maciej L. Goniewicz, Noura O. Kassem, Theodore P. Klupinski, Sandy Liles, Thivanka Muthumalage, Alexandra Noël, David H. Peyton, Qixin Wang, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

Some firms and marketers of electronic cigarettes (e-cigarettes; a type of electronic nicotine delivery system (ENDS)) and refill liquids (e-liquids) have made claims about the safety of ingredients used in their products based on the term "GRAS or Generally Recognized As Safe" (GRAS). However, GRAS is a provision within the definition of a food additive under section 201(s) (21 U.S.C. 321(s)) of the U.S. Federal Food Drug and Cosmetic Act (FD&C Act). Food additives and GRAS substances are by the FD&C Act definition intended for use in food, thus safety is based on oral consumption; the term GRAS cannot serve …

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Classification Of Major Solar Flares From Extremely Imbalanced Multivariate Time Series Data Using Minimally Random Convolutional Kernel Transform, Kartik Saini, Khaznah Alshammari, Shah Muhammad Hamdi, Soukaina Filali Boubrahimi May 2024

Classification Of Major Solar Flares From Extremely Imbalanced Multivariate Time Series Data Using Minimally Random Convolutional Kernel Transform, Kartik Saini, Khaznah Alshammari, Shah Muhammad Hamdi, Soukaina Filali Boubrahimi

Computer Science Faculty and Staff Publications

Solar flares are characterized by sudden bursts of electromagnetic radiation from the Sun’s surface, and are caused by the changes in magnetic field states in active solar regions. Earth and its surrounding space environment can suffer from various negative impacts caused by solar flares, ranging from electronic communication disruption to radiation exposure-based health risks to astronauts. In this paper, we address the solar flare prediction problem from magnetic field parameter-based multivariate time series (MVTS) data using multiple state-of-the-art machine learning classifiers that include MINImally RandOm Convolutional KErnel Transform (MiniRocket), Support Vector Machine (SVM), Canonical Interval Forest (CIF), Multiple Representations Sequence …

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Mantle Sources And Geochemical Evolution Of The Picture Gorge Basalt, Columbia River Basalt Group, Emily B. Cahoon, Martin J. Streck, Richard W. Carlson, Ilya N. Bindeman May 2024

Mantle Sources And Geochemical Evolution Of The Picture Gorge Basalt, Columbia River Basalt Group, Emily B. Cahoon, Martin J. Streck, Richard W. Carlson, Ilya N. Bindeman

Geology Faculty Publications and Presentations

The Columbia River Basalt Group (CRBG) is the youngest continental flood basalt province, proposed to be sourced from the deep-seated plume that currently resides underneath Yellowstone National Park. If so, the earliest erupted basalts from this province, such as those in the Picture Gorge Basalt (PGB), aid in understanding and modeling plume impingement and the subsequent evolution of basaltic volcanism. Using geochemical and isotopic data, this study explores potential mantle sources and magma evolution of the PGB. Long known geochemical signatures of the PGB include overall large ion lithophile element (LILE) enrichment and relative depletion of high field strength elements …

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Valid Confidence Intervals For Μ,Σ When There Is Only One Observation Available, Anirban Dasgupta, Stephen Portnoy May 2024

Valid Confidence Intervals For Μ,Σ When There Is Only One Observation Available, Anirban Dasgupta, Stephen Portnoy

Mathematics and Statistics Faculty Publications and Presentations

Portnoy (2019) considered the problem of constructing an optimal confidence interval for the mean based on a single observation X ∼ N(µ, σ2). Here we extend this result to obtaining 1-sample confidence intervals for σ and to cases of symmetric unimodal distributions and of distributions with compact support. Finally, we extend the multivariate result in Portnoy (2019) to allow a sample of size m from a multivariate normal distribution where m may be less than the dimension.

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Extended Producer Responsibility: Successes, Failures, And The Future Of Oregon Recycling, Zoe Vandal May 2024

Extended Producer Responsibility: Successes, Failures, And The Future Of Oregon Recycling, Zoe Vandal

University Honors Theses

Extended Producer Responsibility (EPR) is a waste management program used globally to improve the recovery, recycling, and management of solid waste materials. There are three types of EPR programs defined by their target materials: electronic and electrical waste (WEEE) EPR, hazardous waste EPR, and packaging EPR. Europe has implemented all three types with relative success. The US has implemented WEEE EPR and hazardous waste EPR and is currently in the process of implementing packaging EPR on a state scale in Oregon, California, Colorado, Maine, and Maryland with 10 more bills being introduced in 2024 alone. Oregon’s EPR program will be …

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Neighboring-Aware Hierarchical Clustering, Ali A. Amer, Muna Al-Razgan, Hassan I. Abdalla, Mahfoudh Al-Asaly, Taha Alfakih, Muneer Al-Hammadi May 2024

Neighboring-Aware Hierarchical Clustering, Ali A. Amer, Muna Al-Razgan, Hassan I. Abdalla, Mahfoudh Al-Asaly, Taha Alfakih, Muneer Al-Hammadi

All Works

In this work, a simple yet robust neighboring-aware hierarchical-based clustering approach (NHC) is developed. NHC employs its dynamic technique to take into account the surroundings of each point when clustering, making it extremely competitive. NHC offers a straightforward design and reliable clustering. It comprises two key techniques, namely, neighboring- aware and filtering and merging. While the proposed neighboring-aware technique helps find the most coherent clusters, filtering and merging help reach the desired number of clusters during the clustering process. The NHC's performance, which includes all evaluation metrics and run time, has been thoroughly tested against nine clustering rivals using four …

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A Computational Investigation Of Wood Selection For Acoustic Guitar, Jonah Osterhus May 2024

A Computational Investigation Of Wood Selection For Acoustic Guitar, Jonah Osterhus

Senior Honors Theses

The acoustic guitar is a stringed instrument, often made of wood, that transduces vibrational energy of steel strings into coupled vibrations of the wood and acoustic pressure waves in the air. Variations in wood selection and instrument geometry have been shown to affect the timbre of the acoustic guitar. Computational methods were utilized to investigate the impact of material properties on acoustic performance. Sitka spruce was deemed the most suitable wood for guitar soundboards due to its acoustic characteristics, strength, and uniform aesthetic. Mahogany was deemed to be the best wood for the back and sides of the guitar body …

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Carrier Mobility In Methylammonium Lead Iodide Perovskite Solar Cells: Mobility Versus Composition In Spin Coated And Vapor Deposited Samples, Max A. Zinman, James Heyman May 2024

Carrier Mobility In Methylammonium Lead Iodide Perovskite Solar Cells: Mobility Versus Composition In Spin Coated And Vapor Deposited Samples, Max A. Zinman, James Heyman

Macalester Journal of Physics and Astronomy

We performed research on a set methylammonium lead iodide (MaPI) perovskite solar cell samples, including samples produced both by vapor deposition and spin coating. We used time resolved THz spectroscopy to measure carrier mobility in the samples and excitation of vibrational modes in the THz and IR spectra to gauge relative sample compositions (ratio of PbI to Ma). Plotting carrier mobilities against composition ratios, we found a peaked distribution of carrier mobilities suggesting an ideal ratio of lead iodide to methylammonium to maximize mobility. We also observed that the spin coated samples had considerably less variance in their composition ratios …

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Effects Of Post-Deposition Annealing On Room Temperature Deposited Zinc Oxide, Ishan Rayen May 2024

Effects Of Post-Deposition Annealing On Room Temperature Deposited Zinc Oxide, Ishan Rayen

Macalester Journal of Physics and Astronomy

This study focuses on thin film deposition of ZnO onto a glass slide using magnetron sputtering. The focus of the study is to understand the effects of post-deposition annealing temperatures. The goal is to optimize crystal quality, conductivity, and transparency. The results attempt to answer the effects of room temperature deposition and changes in film properties once annealed. Annealing temperatures ranged from 100°C to 400°C with an annealing time of 30 minutes. This found an ideal temperature of 250°C for post-deposition annealing, resulting in approximately 3.86 times more conductivity with little to no decrease in transparency. However crystal quality did …

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Probing Charge Recombination In Organic Solar Cells, Ally C. Hurd, Awwad Alotaibi, Acacia Patterson, Obaid Alqahtani, James Doyle, Brian Akira Collins May 2024

Probing Charge Recombination In Organic Solar Cells, Ally C. Hurd, Awwad Alotaibi, Acacia Patterson, Obaid Alqahtani, James Doyle, Brian Akira Collins

Macalester Journal of Physics and Astronomy

Printable and flexible organic solar panels are promising sources of inexpensive, large-scale renewable energy, where panels can be manufactured by printing from polymer inks. There are some limitations to these types of solar cells, however. First, toxic halogenated solvents have historically been necessary to dissolve polymers to make the ink. In addition, organic solar cells typically have high rates of recombination, which limits their efficiency. Here, we use a transient photovoltage (TPV) technique to measure charge lifetimes in cells made from two different organic solvents. The first solvent is toxic, halogenated dichlorobenzene (DCB) which is typically used to make organic …

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Investigation Of Tantalum Sodium Lead Borate Glass Using Laser Ionization Time Of Flight Mass Spectrometry (Litof-Ms), Siri Erickson-Green May 2024

Investigation Of Tantalum Sodium Lead Borate Glass Using Laser Ionization Time Of Flight Mass Spectrometry (Litof-Ms), Siri Erickson-Green

Macalester Journal of Physics and Astronomy

Laser ionization time of flight mass spectrometry (LITOF-MS) is a spectrometry method which can measure, with exceptional accuracy, the composition of ions within a glass system. Additionally, unlike other spectroscopy and spectrometry methods, this technique allows insight into the abundance of each kind of ion within a given glass system. This specific project tackled the topic of tantalum-doped sodium and lead borate glasses, as sodium and lead borate glasses doped with a transition metal is a topic which has not been thoroughly explored. Our group synthesized such a glass and was able to use LITOF-MS to gain insights into how …

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Strain Methods For Changing Local Electric Field Gradient In Bafe2as2, Caleb Williams May 2024

Strain Methods For Changing Local Electric Field Gradient In Bafe2as2, Caleb Williams

Macalester Journal of Physics and Astronomy

In this study, we introduce a novel approach aimed at advancing the investigation of local nematicity in BaFe2As2 via dynamically pulsed strain fields. Our research is motivated by the pursuit of a more sensitive alternative to existing static strain methods. Employing nuclear magnetic resonance techniques, we measure the nuclear quadrupolar energy splittings, utilizing them as a sensitive indicator of the electric field gradient (EFG) that couples strongly to the orbital occupations of the 75As p-orbitals. In the new method, we discern an EFG response through changes in the phase acquired by the nuclear magnetization while time-evolving in the strain field, …

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Linking The Population Of Binary Black Holes With The Stochastic Gravitational-Wave Background, Olivia X. Laske May 2024

Linking The Population Of Binary Black Holes With The Stochastic Gravitational-Wave Background, Olivia X. Laske

Macalester Journal of Physics and Astronomy

The astrophysical stochastic gravitational-wave background (SGWB) is the product of overlapping waveforms that create a single unresolvable background. While current LIGO sensitivity is insufficient to uncover the SGWB, future space-based detectors and Third Generation (3G) experiments are expected to probe deep enough for detection. Predictions of the SGWB can constrain future searches as well as provide insight into star formation, merger history, and mass distribution. Here, three primary methods are used to calculate a theoretical SGWB. The first method integrates over a precomputed mass distribution probability grid, while the second and third employ Monte Carlo integration with simulated data. After …

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Simulation Of Polymerization On Surfaces: Implications For Abiogenesis, Sylvia Greene May 2024

Simulation Of Polymerization On Surfaces: Implications For Abiogenesis, Sylvia Greene

Macalester Journal of Physics and Astronomy

How did life arise from the prebiotic conditions of the early earth? This problem has vexed scientists for decades with no consensus on its solution. Significant spontaneous formation of biopolymers such as proteins and nucleic acids in the aqueous phase appears to be improbable due to thermodynamic constraints. It has been proposed that mineral surfaces could have served as a catalyst for the initial formation of biopolymers. However, the feasibility of this mechanism has not been thoroughly studied. In this study, a particle simulation of polypeptide formation on surfaces is developed to assess the feasibility of this mechanism. Elementary processes …

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The Hodgkin-Huxley Model For Neuron Action Potentials: A Computational Study, Uditi Chandrashekhar May 2024

The Hodgkin-Huxley Model For Neuron Action Potentials: A Computational Study, Uditi Chandrashekhar

Macalester Journal of Physics and Astronomy

Neurons are the fundamental units of the nervous system that receive stimuli as signals and pass on this information to other cells in different parts of the body. An action potential refers to the transmission of the electrical nerve impulse along the neuron. In their seminal work published in 1952, Alan L. Hodgkin and Andrew Huxley proposed a mathematical model of neuronal membrane action potentials based on a series of experiments they conducted using the giant squid neuron. This thesis is a study of the nature of the action potential used to transfer signals along the neuron based on the …

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Variability Of High-Degree Modes Over Multiple Solar Cycles Using Local Helioseismic Data From Gong, Nicholas Cebula, Sushanta Tripathy, Kiran Jain, John M. Cannon May 2024

Variability Of High-Degree Modes Over Multiple Solar Cycles Using Local Helioseismic Data From Gong, Nicholas Cebula, Sushanta Tripathy, Kiran Jain, John M. Cannon

Macalester Journal of Physics and Astronomy

In this investigation we use the local helioseismic technique of ring diagrams to study the power, energy, and damping rates of high degree solar acoustic modes. Our data covers the period from the maximum phase of solar cycle 23 to the ascending phase of cycle 25. The goal is to examine the variations in the mode parameters with solar activity as well as the differences between different cycles. For this, we use different proxies of solar activity. We use 10.7 cm radio flux measurements and a measure of magnetic flux known as magnetic activity index from magnetograms.

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Ammonia Emission In The Milky Way Galactic Bar Dust Lanes, Charles G. Burton May 2024

Ammonia Emission In The Milky Way Galactic Bar Dust Lanes, Charles G. Burton

Macalester Journal of Physics and Astronomy

The Central Molecular Zone (CMZ) of the Milky Way is a region of molecular gas within the inner few hundred parsecs of the Galaxy. This inner region of the Milky Way is hotter and more turbulent when compared with the disk of the Milky Way. Gas is thought to be funneled into the CMZ through dense gaseous dust lanes that are associated with the Galactic Bar. I studied two regions of one of these dust lanes using the NH3 inversion transitions of (J,K) = (1,1), (2,2), (3,3), and (4,4). Data has been obtained from the Green Bank Telescope targeting these …

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Operation Shark: Addressing The Negative Portrayal Of Sharks In Media, Michael R. O'Shea May 2024

Operation Shark: Addressing The Negative Portrayal Of Sharks In Media, Michael R. O'Shea

Masters Theses

Sharks are some of the most well adapted and effective animals in the animal kingdom. Unfortunately, they are also some of the most feared. For many people the word shark evokes images of vicious attacks like those seen in movies such as Jaws. Sharks have also been negatively portrayed in the media. This negative portrayal of sharks has led to misconceptions about sharks that have damaged their populations. Efforts have been made to raise awareness and fight common misconceptions of sharks. However, many people still hold on to the incorrect ideas they have about sharks. This thesis will examine the …

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Extreme Heat & Public Perception In Portland, Oregon: Evidence Of A Compounding Vulnerability Effect For Climate Hazards, Brianne Suldovsky, Molly Baer Kramer, Jonathan Fink May 2024

Extreme Heat & Public Perception In Portland, Oregon: Evidence Of A Compounding Vulnerability Effect For Climate Hazards, Brianne Suldovsky, Molly Baer Kramer, Jonathan Fink

Geology Faculty Publications and Presentations

Extreme heat events are a global public health threat, and the frequency of these events are projected to increase significantly in the coming decades. Responding to extreme heat requires that municipalities communicate with public audiences. Generally speaking, risk communication and public engagement efforts are more effective when they are responsive to current risk perception trends. This social scientific study examines extreme heat risk perceptions, emergency response needs, and level of trust in first responders among residents of the Portland (OR) Metro Area. Using quantitative survey data, it demonstrates the compounding influence of three previously identified vulnerability indicators–poverty, disability, and race–on …

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Supplemental Information. Theoretical Rotational And Vibrational Spectral Data For The Hypermagnesium Oxide Species Mg2o And Mg2o+, Athena R. Flint, Brent R. Westbrook, Ryan C. Fortenberry May 2024

Supplemental Information. Theoretical Rotational And Vibrational Spectral Data For The Hypermagnesium Oxide Species Mg2o And Mg2o+, Athena R. Flint, Brent R. Westbrook, Ryan C. Fortenberry

Faculty and Student Publications

Tables to accompany a forthcoming article in the journal ChemPhysChem.

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Ankle Mobility And Balance In A Healthy College-Aged Population: A Correlational Study, Anna G. Johnson, Madelyn M. Roiger, Elisa M. Stewart May 2024

Ankle Mobility And Balance In A Healthy College-Aged Population: A Correlational Study, Anna G. Johnson, Madelyn M. Roiger, Elisa M. Stewart

Human Kinetics & Applied Health Sciences Student Works

A review of current literature shows a relationship between ankle mobility and balance in an older population, with limited evidence in younger, healthy populations. To bridge this gap, this study aims to explore this relationship in a healthy, college-aged population. Maintaining upright balance is an integrated effort by the vestibular, somatosensory, and visual systems. Regaining a loss of balance happens with three strategies: an ankle strategy for small perturbations, a hip strategy for moderate perturbations, and a stepping strategy for the largest loss to regain a new base of support. Taking these sequential responses into account, the investigators specifically looked …

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