Physical Sciences and Mathematics Commons^™

Maize Leaf Appearance Rates: A Synthesis From The United States Corn Belt, Caio L. Dos Santos, Lori J. Abendroth, Jeffrey A. Coulter, Emerson D. Nafziger, Andrew E. Suyker, Jianming Yu, Patrick S. Schnable, Sotirios V. Archontoulis

School of Natural Resources: Faculty Publications

The relationship between collared leaf number and growing degree days (GDD) is crucial for predicting maize phenology. Biophysical crop models convert GDD accumulation to leaf numbers by using a constant parameter termed phyllochron (°C-day leaf⁻¹) or leaf appearance rate (LAR; leaf ^oC-day⁻¹). However, such important parameter values are rarely estimated for modern maize hybrids. To fill this gap, we sourced and analyzed experimental datasets from the United States Corn Belt with the objective to (i) determine phyllochron values for two types of models: linear (1-parameter) and bilinear (3-parameters; phase I and II phyllochron, and transition …

Testability Of Instrumental Variables In Linear Non-Gaussian Acyclic Causal Models, Feng Xie, Yangbo He, Zhi Geng, Zhengming Chen, Ru Hou, Kun Zhang

Machine Learning Faculty Publications

This paper investigates the problem of selecting instrumental variables relative to a target causal influence X → Y from observational data generated by linear non-Gaussian acyclic causal models in the presence of unmeasured confounders. We propose a necessary condition for detecting variables that cannot serve as instrumental variables. Unlike many existing conditions for continuous variables, i.e., that at least two or more valid instrumental variables are present in the system, our condition is designed with a single instrumental variable. We then characterize the graphical implications of our condition in linear non-Gaussian acyclic causal models. Given that the existing graphical criteria …

Young’S Modulus: Building A Device To Measure Material Strength To Understand Interatomic Bond Stiffness, Daniel A. Nordquist, Emily Grace

Celebration of Research

Young’s Modulus is an equation that is to measure the strength in different materials. A common application of Young’s Modulus is measuring the breaking point of cables. The understanding of the Young’s Modulus equation and its applications is a standard part of the introductory undergraduate physics sequence. We sought to construct a lab apparatus that would enable physics undergraduate students to measure and verify the results of the Young’s Modulus equation. These macroscopic measurements can then be used to further understand inter-atomic bond stiffness. This poster reviews the design, construction, and testing of a Young’s Modulus lab experiment. This lab …

Science Interest And Confidence In Middle School Aged Students, Emily Dobesh, Emily Grace, Karissa Carlson

Celebration of Research

In the middle school science classroom, students begin to decide whether or not they like science. This decision has long term impacts on their interests, future studies, and ultimately career goals. Further, the impact of this decision can be felt by the STEM field when fewer and fewer students are interested in pursuing jobs within the field. To explore the attitudes and confidence of these students towards science and math, the CURE survey and Math Anxiety Scale were adapted to gather data from a group of middle school students after attending a Middle School Science Day event. Through the research, …

Factors That Influence Graduation Rates At Northwestern College, Hailey Louw, Jennifer Schon

Celebration of Research

This project examines factors that influence graduation rates regarding behaviors and choices made in college as opposed to exogenous factors such as family income, race, etc. These factors also included responses from first-year students who took the Cooperative Institutional Research Program (CIRP) survey. Using data from 2013 - 2016 freshman admissions and combining this with CIRP responses from 2014 and 2016, there were found to be five factors related to behavior at college that influenced graduation rates.

Completion of registered hours, campus involvement, and high tuition discount rates had strong, positive correlations with whether the student graduated. Student participation in …

Building A Mach Zehnder Interferometer With Limited Resources, Alyssa Buren, Dylan J. Kirkeby, Daniel A. Nordquist, Gabriel M.J.A. Andres, Emily Grace

Celebration of Research

Interferometers are simple optical devices that function by splitting a coherent light beam. The beam is recombined using beam splitters and mirrors. The addition of the two light beams produces interference patterns in the forms of fringes which can be used to study the path taken by the two beams. This is old technology and we sought to construct an interferometer using rudimentary and cast-off equipment. The purpose is to show that modern physics concepts can be measured inexpensively and by undergraduate student design. Though we had no optics table and or optical mounts, by careful alignment and adjustments to …

Design And Construction Of R.C. Plane, Gabriel Andres, Dylan J. Kirkeby, Seth Druin, Nathan Mohr, Blake Pomajzl

Celebration of Research

This project was started to help students understand how to conduct a proper research project and to gain a general understanding of circuitry and aerodynamics. As undergraduate students, this was practical information and experience. Our project’s goal was to create a functioning airplane made from mainly on-hand pieces. We had to figure out how to improvise and use the resources we had creatively while troubleshooting many problems.

Women Enrollment At Northwestern College, Josiah Bonestroo, Jennifer Schon

Celebration of Research

This project observes the enrollment rate of women at Northwestern College and why it is inconsistent. Data is used from satisfaction surveys of 2020 and 2021 enrollees, with the data being analyzed using R Studio. Types of data observed include type of visits students went on, types of scholarships, and interest in a Christian college atmosphere.

Concept Design For Optical Tweezers To Be Used In Dna Research, Dylan J. Kirkeby, Gabriel Andres, Emily Grace, Karissa D. Carlson, Elizabeth Heeg, Eric Jones

Celebration of Research

Optical tweezers are a Nobel Prize-winning technology capable of trapping microscopic and sub-microscopic particles using a laser beam. There are several new and useful applications available with the use of optical tweezers. A single optical tweezers set up can cost upwards of two hundred thousand dollars; however, we have designed a cost effective set up to study damaged DNA for under thirty thousand dollars. Using this design, we applied for a grant that would give us the necessary funds to build this set up. The building process itself will be very useful hands-on time learning about the laser set up. …

Predicting Student Graduation At A Private College, Theo Jongerius, Jennifer Schon

Celebration of Research

The purpose of this project was to accurately predict which students attending Northwestern will graduate based on information we collect on incoming students, as well as information we gain from students during their time at NWC.

Through use of the programming language Python and its machine learning libraries, I was able to develop a machine learning model that can accurately predict if a student would graduate 85% of the time.

Probing Small Heat Shock Protein Chaperoning Activity Through The Interaction Between Myoglobin And Guanidine Hydrochloride, Jacob Mcdowell

Celebration of Research

Myoglobin is a small biological protein found in most muscle tissues. When in the proper form (native/folded), myoglobin can serve its primary function: binding oxygen. However, like all proteins, myoglobin can denature through a variety of processes into a form that no longer binds oxygen. One denaturant, guanidine hydrochloride (GuHCl), is the biological product of protein metabolism. Another class of biological proteins is small heat shock proteins (sHSPs), which have the function of chaperoning other proteins to prevent the denaturing process. Previously, in physical chemistry lab, we explored the GuHCl-induced denaturing of myoglobin. Former Northwestern students used fluorescence correlation spectroscopy …

Amino Acid Quenching, Steven Van Meeteren

Celebration of Research

Alexa Fluor 594 is a fluorescent molecule commonly used to tag calmodulin, a protein that regulates a variety of cell processes. By measuring fluorescence, scientists can study calmodulin and its interactions with other proteins. However, fluorescence is not the only fate of Alexa Fluor 594. The molecule is also known to transfer energy to coupled amino acids through a mechanism called quenching. The purpose of this experiment was to study the quenching effects of Histidine, Tyrosine, and Methionine on the Alexa Fluor 594. These amino acids’ Stern-Volmer plots suggest static quenching may be occurring. Moreover, the Stern-Volmer plot of Potassium …

Researching The Molecular Components Of Flourish Using Mass Spectroscopy, Lane Mulder

Celebration of Research

We looked into the molecular composition of a liquid probiotic known as Flourish and and the 13 components that make it up using mass spectroscopy.

"Advancing Together." 15th Annual Research Week: Event Proceedings, University Of The Incarnate Word

Research Week Archived Proceedings

Presentations of completed and ongoing research activity conducted by graduate students, undergraduate students, and faculty at University of the Incarnate Word. Includes poster, podium, visual arts, interactive demo, creative and performing arts presentations. Coordinated and presented by the Office of Research and Graduate Studies.

Mp765: Creating The Orono Bog Boardwalk: A Facility For Education, Research, And Recreation, Ronald B. Davis

Miscellaneous Publications

A memoir by Dr. Ronald Davis detailing the creation of the Orono Bog Boardwalk. The Orono Bog Boardwalk is a premier destination in the Bangor/Orono area for persons wishing to experience the beauty and fascinating plants and animals of a Maine bog. The 1-mile boardwalk loop trail begins at the forested wetland edge in the Bangor City Forest, and after 800 feet crosses the Orono town line into the portion of the Orono Bog owned by the University of Maine. Along the way the boardwalk passes through a wide range of changing vegetation and environments on its way to the …

Neumann Problems For P-Harmonic Functions, And Induced Nonlocal Operators In Metric Measure Spaces, Luca Capogna, Josh Kline, Riikka Korte, Nageswari Shanmugalingam, Marie Snipes

Mathematics Sciences: Faculty Publications

Following ideas of Caffarelli and Silvestre in [20], and using recent progress in hyperbolic fillings, we define fractional p-Laplacians (−∆p) θ with 0 < θ < 1 on any compact, doubling metric measure space (Z, d, ν), and prove existence, regularity and stability for the non-homogenous non-local equation (−∆p) θu = f. These results, in turn, rest on the new existence, global Hölder regularity and stability theorems that we prove for the Neumann problem for p-Laplacians ∆p, 1 < p < ∞, in bounded domains of measure metric spaces endowed with a doubling measure that supports a Poincaré inequality. Our work also includes as special cases much of the previous results by other authors in the Euclidean, Riemannian and Carnot group settings. Unlike other recent contributions in the metric measure spaces context, our work does not rely on the assumption that (Z, d, ν) supports a Poincaré inequality.

The Relevance Of Pulsed Electroacoustic Measurements For Spacecraft Charging, Zachary Gibson, J. R. Dennison

Physics Student Research

The magnitude and spatial distribution of charge embedded in dielectric materials and the evolution of the charge distributions with time are at the heart of understanding spacecraft charging. Spacecraft materials are charged primarily by incident fluxes of low energy electrons, with electron fluxes in the 10 keV to 50 keV range often responsible for the largest deleterious arcing effects. While the pulsed electroacoustic (PEA) method can provide sensitive non-destructive measurements of the internal charge distribution in insulating materials, it has often been limited for spacecraft charging applications by typical spatial resolutions of ≤10 μm, with a 10 μm range of …

Silver Bow Creek/Butte Area Npl Site Butte Priority Soils Operable Unit, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Faster Intercalation Pseudocapacitance Enabled By Adjustable Amorphous Titania Where Tunable Isomorphic Architectures Reveal Accelerated Lithium Diffusivity, Wessel Van Den Bergh, Taylor Larison, Maximilliano Jesus Jara Fornerod, Prof. Stefan Guldin, Morgan Stefik

Faculty Publications

Intercalation pseudocapacitance is a faradaic electrochemical phenomenon with high power and energy densities, combining the attractive features of capacitors and batteries, respectively. Intercalation pseudocapacitive responses exhibit surface-limited kinetics by definition, without restriction from the collective of diffusion-based processes. The surface-limited threshold (SLT) corresponds to the maximum voltage sweep rate (vSLT) exhibiting a predominantly surface-limited current response prior to the onset of diffusion-limitations. Prior studies showed increased lithium diffusivity for amorphous titania compared to anatase. Going beyond prior binary comparisons, here a continuum of amorphous titania configurations were prepared using a series of calcination temperatures to tailor both amorphous …

Development And Validation Of An Edna Protocol For Monitoring Endemic Asian Spiny Frogs In The Himalayan Region Of Pakistan, Muhammad Saeed, Muhammad Rais, Ayesha Akram, Maggie R. Williams, Kenneth F. Kellner, Syed A. Hashsham, Drew R. Davis

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Wildlife monitoring programs are instrumental for the assessment of species, habitat status, and for the management of factors affecting them. This is particularly important for species found in freshwater ecosystems, such as amphibians, as they have higher estimated extinction rates than terrestrial species. We developed and validated two species-specific environmental DNA (eDNA) protocols and applied them in the field to detect the Hazara Torrent Frog (Allopaa hazarensis) and Murree Hills Frog (Nanorana vicina). Additionally, we compared eDNA surveys with visual encounter surveys and estimated site occupancy. eDNA surveys resulted in higher occurrence probabilities for both A. …

Hybrid Suspension Tissue Engineering Of A 3d Alveolar Model For Lung And Vascular Disease Modeling, Jonard Corpuz Valdoz

Theses and Dissertations

Tissue engineering is a dichotomy of scaffold-based and scaffold-free cultures. Scaffold-based cultures form highly organotypic structures but with low uniformity and throughput. Conversely, scaffold-free cultures create consistently sized and shaped cell aggregates with limited spheroid-like structure and function, thus restricting their use for accurate disease modeling. We hypothesized that combining aspects of each culturing format, we would produce highly organotypic structures of consistent size and shape for use in pulmonary modeling. First, to improve on culture consistency and output, we created a novel easily scalable, minimalistic design for a micropatterned hydrogel dish that increases reliability and efficiency in 3D cell …

Economic Losses From Covid-19 Cases In The Philippines: A Dynamic Model Of Health And Economic Policy Trade-Offs, Elvira P. De Lara-Tuprio, Ma. Regina Justina E. Estuar, Joselito T. Sescon, Cymon Kayle Lubangco, Rolly Czar Joseph T. Castillo, Timothy Robin Y. Teng, Lenard Paulo V. Tamayo, Jay Michael R. Macalalag, Gerome M. Vedeja

Mathematics Faculty Publications

The COVID-19 pandemic forced governments globally to impose lockdown measures and mobility restrictions to curb the transmission of the virus. As economies slowly reopen, governments face a trade-off between implementing economic recovery and health policy measures to control the spread of the virus and to ensure it will not overwhelm the health system. We developed a mathematical model that measures the economic losses due to the spread of the disease and due to different lockdown policies. This is done by extending the subnational SEIR model to include two differential equations that capture economic losses due to COVID-19 infection and due …

Competitive Sorption And Transport Of Heavy Metals In Soil And Mn Oxide-Coated Sand, Joshua Tyler Padilla

LSU Doctoral Dissertations

This study investigated the competitive sorption of Ni, Pb, and Zn as well as synergistic interactions between Ni and phosphate (P) in soils and Mn oxide-coated sand. During stirred-flow experiments, the sorption of heavy metal cations by Olivier soil was mutually reduced when applied simultaneously. When applied consecutively, the cation of higher affinity was able to displace the cation of lower affinity from the soil surface, however, no evidence for the reverse case was observed. A novel general exchange kinetics model was able to correctly describe such displacement. Competition between Ni and Zn mutually increased mobility in Olivier and Windsor …

Nsea's Future Leaders Of Whatcom County (Flow), Emma Burgess

College of the Environment Internship Reports

During the spring of 2022 I was a Future Leaders of Whatcom County (FLOW) intern with the Nooksack Salmon Enhancement Association (NSEA), a community-based nonprofit organization that educates, inspires, and engages the community to take action to keep wild salmon here for future generations.

This paper will provide a background detailing my motivations and the events that lead me to this internship, a description of NSEA and the specific projects I completed, a discussion of my personal and professional development over the course of the spring, and a collection of my pictures from the season.

New Aspects Of Optical Coherence And Their Potential For Quantum Technologies, Nathaniel Robert Miller

LSU Doctoral Dissertations

Currently, optical technology impacts most of our lives, from light used in scientific measurement to the fiber optic cables that makeup the backbone of the internet. However, as our current optical infrastructure grows, we discover that these technologies are not limitless. Astronomers find themselves unable resolve stars that are too close to one another. Meanwhile, the internet is always under threat as our computer technology improves and more complex ways to break encryption emerge, threatening our personal information and infrastructure. However, our current optical technology functions on classical principles, and can be easily improved by incorporating our knowledge of quantum …

A Numerical Investigation Of Flood And Sediment Dynamics Over The Coastal Watersheds During Hurricane Events, Dongxiao Yin

LSU Doctoral Dissertations

Landfalling tropical cyclones can cause catastrophic floods and sediment disturbance over the coastal watersheds. This study aims to unravel the contribution of different processes to hurricane-induced flooding, to assess the uncertainties in flood modelling and forecasting, and to advance the techniques in sediment simulation over coastal watersheds during hurricanes.

First, I examined the hydrometeorology and hydrology of Hurricane Florence (2018) induced inland flooding. My results suggest that the slow motion in combination with the “L-shaped” path was the most distinctive feature of the hurricane that incurred catastrophic and widespread rainfall and flooding over the Cape Fear River Basin (CFRB).

Second, …

Nature And Student Wellness At Grand Valley State University, Emma Cubitt

Honors Projects

This project discusses the importance of student mental wellness in relation to nature exposure. A pamphlet is provided to educate students on outdoor volunteer opportunities, as well as hiking trails within walking distance of campus.

Unavoidable Structures In Large And Infinite Graphs, Sarah Allred

LSU Doctoral Dissertations

In this work, we present results on the unavoidable structures in large connected and large 2-connected graphs. For the relation of induced subgraphs, Ramsey proved that for every positive integer r, every sufficiently large graph contains as an induced subgraph either K_r or K_r. It is well known that, for every positive integer r, every sufficiently large connected graph contains an induced subgraph isomorphic to one of K_r, K_1,r, and P_r. We prove an analogous result for 2-connected graphs. Similarly, for infinite graphs, every infinite connected graph contains an induced subgraph …

Environmental Decision Support Systems As A Service: Demonstration On Ce-Qual-W2 Model, Yoav Bornstein, Ben Dayan, Amir Cahn, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

An environmental decision support system (EDSS) can be used as an important tool for the rehabilitation and preservation of ecosystems. Nonetheless, high assimilation costs (both money and time) are one of the main reasons these tools are not widely adopted in practice. This work presents a low-cost paradigm of “EDSS as a Service.” This paradigm is demonstrated for developing a water quality EDSS as a service that utilizes the well-known CE-QUAL-W2 model as a kernel for deriving optimized decisions. The paradigm is leveraging new open-source technologies in software development (e.g., Docker, Kubernetes, and Helm) with cloud computing to significantly reduce …

Ubjective Information And Survival In A Simulated Biological System, Tyler S. Barker, Massimiliano Pierobon, Peter J. Thomas

School of Computing: Faculty Publications

Information transmission and storage have gained traction as unifying concepts to characterize biological systems and their chances of survival and evolution at multiple scales. Despite the potential for an information-based mathematical framework to offer new insights into life processes and ways to interact with and control them, the main legacy is that of Shannon’s, where a purely syntactic characterization of information scores systems on the basis of their maximum information efficiency. The latter metrics seem not entirely suitable for biological systems, where transmission and storage of different pieces of information (carrying different semantics) can result in different chances of survival. …