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From Hector Mine M7.1 To Ridgecrest M7.1 Earthquake. A Look From A 20-Year Perspective, Sergey Pulinets, Marina Tsidilina, Dimitar Ouzounov, Dmitry Davidenko

Mathematics, Physics, and Computer Science Faculty Articles and Research

The paper provides a comparative analysis of precursory phenomena in the ionosphere and atmosphere for two strong earthquakes of the same magnitude M7.1 that happened in the same region (North-East from Los Angeles) within a time span of 20 years, the Hector Mine and Ridgecrest earthquakes. Regardless of the similarity of their location (South-Eastern California, near 160 km one from another), there was one essential difference: the Hector Mine earthquake happened during geomagnetically disturbed conditions (essential in the sense of ionospheric precursors identification). In contrast, the quiet geomagnetic conditions characterized the period around the time of the Ridgecrest earthquake. The …

Effects Of Estuary-Wide Seagrass Loss On Fish Populations, Jennifer K. O'Leary, Maurice C. Goodman, Ryan K. Walter, Kariss Willits, Daniel J. Pondella

Physics

Globally, habitat loss in coastal marine systems is a major driver of species decline, and estuaries are particularly susceptible to loss. Along the United States Pacific coast, monospecific eelgrass (Zostera marina) beds form the major estuarine vegetated habitat. In Morro Bay, California, eelgrass experienced an unprecedented decline of > 95%, from 139 ha in 2007 to < 6 ha by 2017. Fish populations were compared before and after the eelgrass decline using trawl surveys. Beach seines surveys were also conducted during the post-decline period to characterize species within and outside of remnant eelgrass beds.While the estuary-wide loss of eelgrass did not result in fewer fish or less biomass, it led to changes in species composition. The post-eelgrass decline period was characterized by increases in flatfish (mainly Citharichthys stigmaeus) and staghorn sculpin (Leptocottus armatus), and decreases in habitat specialists including bay pipefish (Syngnathus leptorhynchus) and shiner perch (Cymatogaster aggregata). There were similar trends inside and outside of remnant eelgrass patches. These findings support evidence across multiple ecosystems suggesting that the predominance of habitat-specialists predicts whether or not habitat loss leads to an overall decline in fish abundance. In addition, loss of critical habitats across seascapes can restrict population connectivity and lead to range contraction. For bay pipefish, the loss of eelgrass in Morro Bay is likely to create a population biogeographic divide. Currently, Morro Bay is dominated by flatfish and sculpins, and the longevity of this new ecosystem state will depend on future eelgrass recovery dynamics supported by ecosystem-based management approaches.

Dietary Flexibility Of Wood Storks In Response To Human-Induced Rapid Environmental Change, Betsy A. Evans, Jessica A. Klassen, Dale E. Gawlik

United States Department of Agriculture Wildlife Services: Staff Publications

Human-induced rapid environmental change (HIREC) has altered landscape processes and negatively impacted many species globally. Some of the most dramatic changes have been in wetlands where flows have been disrupted, and new wetlands have been created to retain runoff. In response to disrupted natural wetland conditions, Wood Stork (Mycteria americana) populations in South Florida have significantly declined over the past several decades. Despite the well-documented sensitivity of Wood Storks to natural wetland conditions, Wood Storks are often observed foraging in roadside created wetlands; however, the availability of prey in created wetlands is currently unknown. We sampled natural and created wetlands …

Surficial Geology Of The Continental Shelf Off New Hampshire: Morphologic Features And Surficial Sediment, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani, Rachel C. Morrison

Center for Coastal and Ocean Mapping

The continental shelf off New Hampshire (NH) in the Western Gulf of Maine (WGOM) is extremely complex and includes extensive bedrock outcrops, marine-modified glacial deposits, marine-formed shoals, seafloor plains, and associated features that are composed of a range of sediment types from mud to gravel. Furthermore, the physiography and composition of the seafloor frequently changes dramatically over relatively short distances (tens of meters). The complexity of the WGOM seafloor results from the interplay of glaciations, sea-level fluctuations, and marine processes (waves and currents). High-resolution multibeam echosounder (MBES) bathymetry and backscatter surveys, along with ground truth consisting of archived seismic reflection …

Confirmative Evaluation: New Cipp Evaluation Model, Tia L. Finney

Journal of Modern Applied Statistical Methods

Struggling trainees often require a substantial investment of time, effort, and resources from medical educators. An emergent challenge involves developing effective ways to accurately identify struggling students and better understand the primary causal factors underlying their poor performance. Identifying the potential reasons for poor performance in medical school is a key first step in developing suitable remediation plans. The SOM Modified Program is a remediation program that aims to ensure academic success for medical students. The purpose of this study is to determine the impact of modifying the CIPP evaluation model by adding a confirmative evaluation step to the model. …

Cost Estimating Using A New Learning Curve Theory For Non-Constant Production Rates, Dakotah Hogan, John J. Elshaw, Clay M. Koschnick, Jonathan D. Ritschel, Adedeji B. Badiru, Shawn M. Valentine

Faculty Publications

Traditional learning curve theory assumes a constant learning rate regardless of the number of units produced. However, a collection of theoretical and empirical evidence indicates that learning rates decrease as more units are produced in some cases. These diminishing learning rates cause traditional learning curves to underestimate required resources, potentially resulting in cost overruns. A diminishing learning rate model, namely Boone’s learning curve, was recently developed to model this phenomenon. This research confirms that Boone’s learning curve systematically reduced error in modeling observed learning curves using production data from 169 Department of Defense end-items. However, high amounts of variability in …

The Life History And Population Dynamics Of Southern Flounder, Kenneth A. Erickson

LSU Master's Theses

Southern Flounder, Paralichthys lethostigma, are a coastal, estuarine-dependent flatfish species that inhabits the Southeastern US Atlantic Ocean and Gulf of Mexico. Throughout their range, Southern Flounder are exploited by both commercial and recreational fisheries. Recently, numerous sources have expressed concerns about Southern Flounder populations, with stock assessments indicating declines in spawning stock biomass and recruitment. To estimate life history traits needed for informed management, such as age, growth, and maturity, I collected 327 Southern Flounder from Louisiana and obtained 14,184 historical records from the Louisiana Department of Wildlife and Fisheries. Using a von Bertalanffy growth equation in a Bayesian …

Excitons In Self-Assembled Hybrid Systems Of Molecular Aggregate Light-Harvesting Nanotubes: Charge-Transfer Substrates And Solution-Stabilized Nanocomposites, Kara Ng

Dissertations, Theses, and Capstone Projects

Delocalized Frenkel excitons-coherently-shared excitations among chromophores-are responsible for the remarkable effciency of supramolecular light-harvesting aggregates within photosynthetic organisms. Despite tremendous progress towards a deeper understanding of these photosynthetic complexes, as well as progress in the development of organic solar cells, the possibility of using bio-inspired molecular nanostructures for large-scale solar energy conversion has not been realized yet. The persistent limitations in translating natures design principles for applications in optoelectronic devices have been the supramolecular structures fragility, and the Frenkel excitons delicate nature. The structural instability, both dis-assembly and spontaneous re-assembly of aggregates. Analysis of the absorption spectrum of a model …

Von Neumann's Minimax Theorem For Continuous Quantum Games, Luigi Accardi, Andreas Boukas

Journal of Stochastic Analysis

No abstract provided.

From Drought To Flood: A Water Balance Analysis Of The Tuolumne River Basin During Extreme Conditions (2015–2017), Andrew R. Hedrick, Danny Marks, Hans-Peter Marshall, James Mcnamara, Scott Havens, Ernesto Trujillo

Geosciences Faculty Publications and Presentations

The degree to which the hydrologic water balance in a snow‐dominated headwater catchment is affected by annual climate variations is difficult to quantify, primarily due to uncertainties in measuring precipitation inputs and evapotranspiration (ET) losses. Over a recent three‐year period, the snowpack in California's Sierra Nevada fluctuated from the lightest in recorded history (2015) to historically heaviest (2017), with a relatively average year in between (2016). This large dynamic range in climatic conditions presents a unique opportunity to investigate correlations between annual water availability and runoff in a snow‐dominated catchment. Here, we estimate ET using a water balance approach where …

A Numerical Approach To Modeling Submoons And Investigating Stability Regions, Josephine Spiegelberg

Honors Program Theses

The recent discovery of the Neptune-sized exomoon candidate Kepler-1625bi (Teachey et al. 2018) has prompted a wave of research into the possibility of such a large satellite hosting its own moons, or submoons. These submoons have a lot in common with moons, and lessons from moon stability calculations can help to understand submoon behavior and stability. Past submoon research has focused on determining stability regions for these submoons using simplified models of the body’s tidal evolution (Reid 1973, Conrad 1985, Kollmeier and Raymond 2019). In order to provide a more detailed understanding of submoon behavior, a Fortran N-Body code was …

A Review Of Nyoongar Responses To Severe Climate Change And The Threat Of Epidemic Disease—Lessons From Their Past, Francesca Robertson, Jason Barrow

Research outputs 2014 to 2021

Nyoongar people have lived in the South West of Western Australia for at least 50,000 years. During that time, they experienced significant climate change, including wide variations in temperature and rainfall, and hundreds of metres’ difference in sea levels. Nyoongar people have a long memory, and climate change is described in their stories and in the knowledge they hold about how life was lived in earlier times. There are artifacts and places that have been manipulated to be productive despite severe drought. COVID-19 disrupted the writing of this article, and the authors felt it appropriate to include Nyoongar responses to …

Assessing The Hierarchy Of Long-Term Environmental Controls On Diatom Communities Of Yellowstone National Park Using Lacustrine Sediment Records, Victoria Chraibi, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

An ecosystem’s ability to maintain structure and function following disturbance, defined as resilience, is influenced by a hierarchy of environmental controls, including climate, surface cover, and ecological relationships that shape biological community composition and productivity. This study examined lacustrine sediment records of naturally fishless lakes in Yellowstone National Park to reconstruct the response of aquatic communities to climate and trophic cascades from fish stocking. Sediment records of diatom algae did not exhibit a distinct response to fish stocking in terms of assemblage or algal productivity. Instead, 3 of 4 lakes underwent a shift to dominance by benthic diatom species from …

Historic And Contemporary Use Of Catfish Aquaculture By Piscivorous Birds In The Mississippi Delta, Paul C. Burr, Jimmy L. Avery, Garrett M. Street, Bronson K. Strickland, Brian S. Dorr

United States Department of Agriculture Wildlife Services: Staff Publications

Piscivorous birds are the primary source of catfish (Ictalurus spp.) depredation at aquaculture facilities in northwestern Mississippi. Of particular concern is the Double-crested Cormorant (Phalacrocorax auritus), which can cost aquaculture producers millions of dollars annually through the depredation of cultured fish. Historical research conducted in the early 2000s estimated cormorant use of aquaculture ponds in the region, but aquaculture area has decreased by more than 70% since those estimates were made. With less aquaculture available, we predicted cormorant densities on aquaculture would be greater today than historically. Applying a similar methodology as in historical studies, we used …

Advancing Quantitative Understanding Of Escherichia Coli Concentrations In A Contemporary Mixed Land-Use Watershed, In West Virginia, Usa, Fritz Petersen

Graduate Theses, Dissertations, and Problem Reports (ETD)

A scarcity of field-based research investigating the relationships between E. coli (fecal matter) concentration, suspended particulate matter (SPM; including size distribution), physicochemical parameters (water temperature, pH, SPC, DO, chloride) and land use practices and the importance of these relationships, particularly for human health, policy makers, and water resource managers, provided the impetus for this research. A 22-site, nested-scale, experimental watershed study design was implemented to investigate E. coli concentrations and the aforementioned relationships in a contemporary mixed land use watershed in the Appalachian region of the eastern United States. Results from a reduced (n=4 sites) study showed SPM in the …

An Investigation Into Weather's Effect On Aerosol Particles Using Wrf And Mapss, Hayden Webb, Devin Smoot

Student Research

Aerosols are solid or liquid particles suspended in air or gas. Many processes contribute to increased aerosol particles in the atmosphere, such as winds, ocean waves, and industrial exhaust. Once suspended, particles can be carried thousands of miles before being returned to the ground by gravity or rain. Some particles can be suspended for several years and travel all around the world, these particles have the greatest impact on climate and weather.

Reproductive Parameters And Female Breeding Season Survival Of Rio Grande Wild Turkeys In South Central Texas, Jacob White

LSU Master's Theses

Historically, Rio Grande wild turkeys in south central Texas have been at lower densities than other portions of the state. Within the Oak-Prairie Wildlife District of Texas, Rio Grande wild turkey regulatory restrictions are different for counties in the eastern and western portions of the ecoregion. Due to perceived increases in turkey density in the eastern portion of the ecoregion (hereafter 1-bird zone), Texas Parks and Wildlife Department (TPWD) considered increasing the bag limit to match counties in the western portion of the district (hereafter 4-bird zone) in order to increase hunting opportunities. However, if regulatory changes are to be …

The Convergence Of Financial And Esg Materiality: Taking Sustainability Mainstream, Ruth Jebe

Management Faculty Publications and Presentations

Sustainability reporting can be seen as an attempt to bring improved environmental, social, and governance (ESG) practices to mainstream business. However, this movement to mainstream is hampered by the disconnect between financial and ESG information. Both reporting streams use the concept of materiality to shape firms’ disclosure obligations, but the term carries different meanings for different organizations. One sustainability organization, the Sustainability Accounting Standards Board (SASB), has developed reporting standards to merge sustainability and financial information by leveraging the definition of materiality for financial reporting purposes. This use of financial materiality positions the SASB to collide with the Security and …

Synthesizing Field And Experimental Techniques To Investigate The Enigmatic Processes Occurring At The Base Of Pyroclastic Currents, Nicholas M. Pollock

Boise State University Theses and Dissertations

Pyroclastic currents are the deadliest hazard associated with explosive volcanic eruptions. These gravity-driven currents consist of volcanic gases and solid particles that range in size from fine ash to boulders. The dangers associated with pyroclastic currents stem from their unpredictability and ability to travel extremely long distances, sometimes in excess of 100 km. To mitigate the risk to populations and infrastructure, we must understand the processes that control the runout distance of pyroclastic currents. The runout distance depends on the complex interplay of processes related to sediment transport, erosion, and deposition. Historically, studies focused on understanding sediment transport and deposition, …

The Photoelectric Effect: Project-Based Undergraduate Teaching And Learning Optics Through A Modern Physics Experiment Redesign, Corneliu Rablau, Uma Ramabadran, Brendan Book, Robert Cunningham

Physics Presentations And Conference Materials

The photoelectric effect is a cornerstone textbook experiment in any Modern Physics or Advanced Laboratory course, designed to verify Einstein’s theory of the photoelectric effect, with the implicit determination of an experimental value for Planck’s constant and the demonstration of the particle nature of light. The standard approach to the experiment is to illuminate the light-sensitive cathode of a vacuum-tube photocell with monochromatic light of known wavelengths; a reversed-voltage is then applied to the photocell and adjusted to bring the photoelectric current to zero. The stopping voltage is then plotted as a function of the inverse wavelength or frequency of …

Long-Term Patterns In Remotely-Sensed Vegetation Productivity For A Transboundary Conservation Area In Southern Africa., Liam Resener

College of Arts & Sciences Senior Theses

In the past century, researchers have observed changes in vegetation productivity and structure in savannas across the world. These changes, caused by shifts in precipitation patterns, fire patterns, soil nutrients, herbivory, and land management decisions, are important to understand because they affect availability of natural resources, which in turn affects the livelihoods of local populations. This study centers on the Kavango-Zambezi Transfrontier Conservation Area (KAZA), a transboundary conservation area that spans five countries in Southern Africa comprised of large areas of protected land. Using the Normalized-Difference Vegetation Index (NDVI), I tested a 35-year remotely-sensed time series for intra- and inter-annual …

Historical Study Of The Relationship Between The Federal Funds Rate And The Inflation Rate, Aaron Wilkins

Undergraduate External Publications

It is believed that in order to control high inflation rates, the Federal Reserve Bank (“the Fed”) increases the federal funds rate and when the inflation rate gets low, the Fed takes the opposite approach. (The federal funds rate is a rate of interest that banks charge each other to lend funds and stay above the reserve requirement, set by the government.) This project examines the relationship between the federal funds rate and the inflation rate. Sixty-five years of historical inflation rates and federal funds rates were used as the basis for this exploration. Because a time lag between the …

Mathematics Of The Infinite God In The Works Of Nicholas Of Cusa, Lauren Henderson

Beets Paper Contest

The geometrical analyses of infinity exemplified in the work of Nicholas of Cusa can aid in understanding the complex nature of God’s attributes, specifically the perceived tension between his simplicity and his quality of encompassing and upholding all things.

The Evolution Of Technology In Call Centers, Julieo Stephen Thompson

CCAC Theses and Dissertations

Historical research was conducted through literature. The report traces the evolution of technology in call centers (CCs) from their early inception to 2018. CCs are integrated into many facets of multidisciplinary areas of business, industry, and public and private institutions of higher education. Three research questions were addressed:

1. What technologies enabled the start of CCs? How did the communications between customers and CSRs take place? What was the content of the earlier communications?
2. How did services and communications evolve as technology matured?
3. What are the current state-of-the-art technologies that exist in CCs? Which industries appear to have the best solutions? …

Employer Strategies For Improving Employee Work-Life Balance, Vernessa Lashawn Johnson-Hoffman

Walden Dissertations and Doctoral Studies

Senior leaders who fail to implement work-life balance strategies may experience reduced profits and sustainability challenges. This single case study explored employers' strategies for improving employee work-life balance. The population for the study included 4 senior leaders of a hospice care agency in North Carolina who successfully implemented employee work-life balance strategies. Data were collected from semistructured interviews and from the review of company documents, website, and social media pages. The conceptual framework for the study was the transformational leadership theory. The trustworthiness of interpretations was supported by member checking. Four themes emerged from inductive analysis of the data: a …

Hazardous Waste Site Proximity And Type 2 Diabetes: From Youths To Adults, Theresa Ann Johnson

Walden Dissertations and Doctoral Studies

Type 2 diabetes has reached epidemic proportions in adults and youths. Persistent organic pollutants and endocrine-disrupting chemicals (EDCs), such as pesticides, dioxins, and organochlorines, are omnipresent and persist in the environment with potential for human exposure via contaminated air, waterways, soil, and human food supply. EDCs have been correlated with diabetes incidence and risks. Residential proximity to hazardous waste sites (HWS) has been correlated with increased hospital admission rates for diabetes. The study used a sample population (N = 1,724), ages ≥ 12 years from the 2005-2012 Continuous NHANES and HWS data from the National Priorities List of Superfund Sites. …

Detecting Soil Macrofauna Using Ground-Penetrating Radar, Melanie N. Stock, David J. Hart, Nicholas J. Balster

Plants, Soils, and Climate Faculty Publications

Fossorial amphibians spend up to ten months belowground, but research into this critical habitat has been impeded by a lack of noninvasive detection methods. Ground-penetrating radar (GPR), however, offers a promising tool because amphibians have theoretically strong electromagnetic (EM) contrasts relative to the soil matrix, and thus potentially high detectability. The objectives of this study were to (1) evaluate GPR by (2) experimentally-inducing three soil thermal regimes that promote stratification in the burrowing depths of 15 Eastern American Toads (Anaxyrus americanus americanus) during the winter of 2011–2012 in Madison, WI, USA. We calculated reflectability and established the unique …

A Deep Dive Into The Land Development Dynamics Of A Complex Landscape, Pariya Pourmohammadi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Land development is a complex and dynamic process simultaneously interacting with numerous environmental, cultural and economic procedures. In this research we studied past, present and future of land transformation in Appalachia. This dissertation is organized in three-essay format and each essay is focused on one aspect of land development processes in a sub-region in the Appalachian region. In the first essay, deep learning techniques are used to build predictive models for the land development. This study presets deconvolutional neural networks models in predicting land development. On the second essay, spatial data analysis and remote sensing are used to investigate the …

Mechanisms For The Incorporation And Distribution Of Radionuclides In Near-Surface Fallout, Marc Alan Fitzgerald

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fallout is the radioactive glass formed from a mixture of vaporized anthropogenic materials with proximate environmental material. These glassy byproducts constitute a compositional record of environmental materials such as soil and vapor precursors that are responsible for chemical heterogeneity in the glasses. The work of this dissertation is to untangle these different sources of compositional heterogeneity, distinguishing low-abundance vaporized anthropogenic-rich material from natural compositions, in order examine soil behavior and chemical evolution during fallout formation. Unfortunately, mixing convolutes the multivariate elemental relationships in these melts due to overlapping element abundances that might distinguish different source materials and chemical behaviors, making …

Spatial And Temporal Structure Of A Canid Community In Nebraska, Lucia Corral Hurtado

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding patterns of space-use by individuals, their distribution, and how they coexist with ecologically similar species is crucial to address various issues in ecology, evolution, conservation biology, and wildlife management. However, the study of such patterns challenging because the relationship among species and their environment is shaped by multiple ecological processes, many of which are acting at different scales, often in a hierarchical manner. In the Canidae family, for instance, where interference competition appears critical, larger species such as coyotes (Canis latrans), can often affect smaller species, such as red fox (Vulpes vulpes) and swift fox …