Life Sciences Commons^™

Using Structural Equation Modeling To Model Compliance With Covid-19 Related Non-Pharmaceutical Interventions Amongst University Students In The United States, Spencer G. Shumway, Jonas D. Hopper, Ethan R. Tolman, Daniel G. Ferguson, Gabriella Hubble, David Patterson, Jamie Jensen

ScholarsArchive Data

There are two data files. The "General Data" comes from a nationwide poll using Qualtrics polling software. The "Utah Data" comes from undergraduate biology students at UVU and BYU. The survey gathered demographic data and attitudes toward the COVID pandemic.

Classification Of Planetary Craters Using Outline-Based Morphometrics, Thomas J. Slezak, Jani Radebaugh, Eric H. Christiansen, Mark C. Belk

Faculty Publications

The morphologies of craters on planetary surfaces reveal clues about the geologic mechanisms by which they originate and subsequently evolve, as well as the materials and physical variables inherent to the environment in which they formed. We carried out a quantitative multivariate analysis of shape descriptors derived from the outlines of craters formed by volcanic processes on Mars, Io, and Earth and by impact cratering on the Moon using elliptic Fourier analysis (EFA) and the Zahn-Roskies (Z-R) shape function. Canonical variate analysis (CVA) was used to construct a statistical model of differences between the crater groups to classify …

Predators As Agents Of Selection And Diversification, Jerald B. Johnson, Mark C. Belk

Faculty Publications

Predation is ubiquitous in nature and can be an important component of both ecological and evolutionary interactions. One of the most striking features of predators is how often they cause evolutionary diversification in natural systems. Here, we review several ways that this can occur, exploring empirical evidence and suggesting promising areas for future work. We also introduce several papers recently accepted in Diversity that demonstrate just how important and varied predation can be as an agent of natural selection. We conclude that there is still much to be done in this field, especially in areas where multiple predator species prey …

Predictors Of Psychosocial And Physiological Distress In Colorectal Cancer Patients, Hyrum Eddington

Undergraduate Honors Theses

Distress among cancer patients has been broadly accepted as an important indicator of patient well-being. However, questions remain such as what patient characteristics are associated with high distress and whether patient-reported distress is correlated with distress biomarkers. To answer these questions, we performed a survey study of 238 colorectal patients in which we assessed patient-reported distress, possible contributors to that distress, and patient anxiety and depression. We also abstracted demographic and clinical information from patient charts and collected measures for salivary cortisol and sarcopenia. We conducted bivariate statistical analyses between patient demographics, clinical factors, and psychosocial measures with our three …

Morphometric Response Of Galaxias Maculatus (Jenyns) To Lake Colonization In Chile, Margaret Mercer, Peter C. Searle, Roberto Cifuentes, Evelyn Habit, Mark C. Belk

Faculty Publications

Body and head shape in fish responds to environmental factors such as water flow rate, food sources, and niche availability. However, the way in which fish respond to these environmental factors varies. In Central Chile, multiple river and lake systems along the coast provide an ideal study site to investigate these types of shape changes. We use geometric morphometrics to characterize shape differences in Galaxias maculatus (Jenyns) between river and lake populations. Lake fish converge on a shape with a more fusiform body, narrower head, and larger eyes, while river fish have a more robust body, rounder head, and smaller …

Life History Divergence In Livebearing Fishes In Response To Predation: Is There A Microevolution To Macroevolution Barrier?, Mark C. Belk, Spencer J. Ingley, Jerald B. Johnson

Faculty Publications

A central problem in evolutionary biology is to determine whether adaptive phenotypic variation within species (microevolution) ultimately gives rise to new species (macroevolution). Predation environment can select for trait divergence among populations within species. The implied hypothesis is that the selection resulting from predation environment that creates population divergence within species would continue across the speciation boundary such that patterns of divergence after speciation would be a magnified accumulation of the trait variation observed before speciation. In this paper, we test for congruence in the mechanisms of microevolution and macroevolution by comparing the patterns of life history divergence among three …

A Brief Overview Of Burst Suppression: Causes And Effects On Mortality In Critical Illness, Jake Hogan, Haoqi Sun, Hassan Aboul Nour, Stephen Piccolo, Jacob Crandall, Steven Peck, M Brandon Westover

Undergraduate Honors Theses

This thesis examines the effects of brain inactivation (burst suppression) on mortality in mechanically ventilated ICU patients. Past research has associated burst suppression with increased mortality. However, the effects of burst suppression on ICU patients while taking into account the relative contributions of propofol (a sedative), and critical illness to mortality, and whether preventing burst suppression might reduce mortality, has not yet been quantified. This thesis explores this relationship, and the effect of critical illness and propofol infusion on burst suppression to understand what drives burst suppression.

To measure the relationship between burst suppression, critical illness, propofol infusion, and mortality, …

Does Negative Frequency-Dependent Selection Maintain Gonopodial Asymmetry In A Livebearing Fish?, Mary-Elise Johnson

Undergraduate Honors Theses

How genetic variation is maintained in the face of strong natural selection is an important problem in evolutionary biology. Selection should erode genetic diversity, leading to more and more homogeneous populations. Yet in nature, we commonly see high degrees of genetic variation, even for traits that are important to fitness. Negative frequency-dependent selection, a balancing selective force that favors traits when they are rare but not when they are common, is a mechanism proposed to maintain polymorphisms in a population. However, there is little empirical data to demonstrate how negative frequency-dependent selection sustains variation. Xenophallus umbratilis is a bilaterally symmetrical …