Life Sciences Commons^™

Effects Of A Peer-Assisted Physical Activity Program On Depression And Anxiety In College Students, Crystal Stroud

Cal Poly Humboldt theses and projects

The purpose of this qualitative study was to examine the effects of a peer-assisted, self-selected physical activity program on depression and anxiety in students at a four-year university, and to explore the various possible mechanisms by which depression and anxiety were affected. These mechanisms included physical activity, self-efficacy, relatedness, competence, and autonomy. A secondary purpose was to examine the benefits of participation for the physical activity buddies who provided the peer-support. In-depth interviews were conducted with three program participants with depression and/or anxiety, six physical activity buddies who supported the participants, and three referring professional healthcare providers. A qualitative data …

Restoration And Tree Drought Resistance In Coast Redwood-Douglas-Fir Forests At Redwood National Park, California, Laura Lalemand

Cal Poly Humboldt theses and projects

With the growing impacts of climate change worldwide and great uncertainty about forests’ vulnerability to a changing climate in the Pacific Northwest, knowledge of coast redwood forest response is crucial. Many of the studies investigating forest response to drought focus on inland forest types rather than coastal forests. This study examined tree growth and drought response in coastal forests at restoration thinning sites, evaluating responses to local climate, tree-level competition, and site-level factors. Tree cores were extracted from previously harvested stands at three restoration sites in Redwood National Park, California, from both thinned and unthinned stands. Douglas-fir (Pseudotsuga menziesii …

Rangewide Tidewater Goby Occupancy Survey Using Environmental Dna, Michael Sutter

Cal Poly Humboldt theses and projects

Rangewide monitoring of fish species is critical for determining status and trends in abundance and distribution; however, implementations of large-scale distribution surveys have generally been constrained by time and cost. This study uses environmental DNA (eDNA) to monitor the presence or absence of two endangered tidewater goby species, the northern tidewater goby (Eucyclogobius newberryi) and the southern tidewater goby (Eucyclogobius kristinae), across their combined geographic range that encompasses the entire California coast (1,350 km).A multi-scale occupancy model designed specifically for eDNA methods was used to account for imperfect detection and to estimate true site occupancy. A …

Apparent Survival Of Snowy Plovers Varies Seasonally, Nora C. Papian

Cal Poly Humboldt theses and projects

Survival is an important vital rate that contributes to population viability, but is infrequently monitored and studied, especially compared to productivity. Furthermore, factors that limit survival and the relative effect on survival are often unknown. I used mark-resight observations of a small (~350) population of threatened Snowy Plovers (Charadrius nivosus nivosus) to quantify seasonal and annual variation in survival and movement between three coastal locations across ~70 km in Humboldt County, California. The return of individuals to non-breeding flocks at three locations was high between years (75-81%). Movement between three locations varied greatly, although most (n = 137) …

Extending The Fossil Record Of The Polytrichaceae (Bryophyta): Insights From The Early Cretaceous Of Vancouver Island, Canada, Alexander C. Bippus

Cal Poly Humboldt theses and projects

Diverse in modern ecosystems, mosses are dramatically underrepresented in the fossil record. Furthermore, most pre-Cenozoic mosses are known only from compression fossils, which lack detailed anatomical information. Lower Cretaceous deposits at Apple Bay (Vancouver Island, British Columbia, Canada) contain a diverse anatomically preserved flora that includes numerous bryophytes, many of which have yet to be characterized. Among them is a polytrichaceous moss that is described here as Meantoinea alophosioides gen. et sp. nov. Meantoinea alophosioides represents the first occurrence of gemma cups in a fossil moss and is the oldest unequivocal record of Polytrichaceae, providing a hard minimum age for …

The Effects Of Ocean Acidification And Reduced Oxygen On The Behavior And Physiology Of Juvenile Rockfish, Corianna H. Flannery

Cal Poly Humboldt theses and projects

As climate change progresses, the frequency and duration of upwelling events that bring low pH, low dissolved oxygen (DO) water to nearshore habitats are expected to increase. In addition, long-term global changes in ocean pH and DO are expected to occur within the next few decades to centuries. Locally, there have been documented reductions in near-shore pH along with the expansion of oxygen minimum zones within the California Current System. However, very few studies have investigated the potential interactive effect of these stressors on temperate reef fish. For this thesis, two sets of laboratory experiments were conducted to determine the …

The Interactive Effects Of Ocean Acidification, Food Availability, And Source Location On The Growth And Physiology Of The California Mussel, Tharadet Daniel Man

Cal Poly Humboldt theses and projects

Research shows ocean acidification (OA) can have largely negative impacts on marine organisms and ecosystems. Prior laboratory studies show that shelled marine invertebrates (e.g., molluscs) exhibit reduced growth rates and weaker shells when experiencing OA-related stress. However, populations of the critical intertidal mussel species, Mytilus californianus, which experience naturally acidic water due to upwelling in certain parts of Northern California have been observed to have relatively stronger and thicker shells and higher growth rates than those that experience less frequent exposure to upwelling. To address the discrepancies between negative effects of OA exposure in the laboratory and seemingly positive …

A New Anatomically-Preserved Plant From The Lower Devonian Of Quebec (Canada): Implications For Euphyllophyte Phylogeny And Early Evolution Of Structural Complexity, Selin Toledo

Cal Poly Humboldt theses and projects

An abrupt transition in the fossil record between Early Devonian plants with simple structure and structurally-complex later Devonian plants, has frustrated efforts to understand patterns of phylogeny across the Early/Middle Devonian boundary and the evolution of complex forms. Both these aspects have important implications for lignophyte and seed plant evolution. In the first chapter, I evaluate phylogenetic relationships between the earliest seed plants, Aneurophytales, and Stenokoleales, using comprehensive taxon sampling (28 species, including all relevant permineralized species) and a set of 40 discrete and nine continuous morpho-anatomical characters. Analysis of this dataset supports the three traditional taxonomic groups (seed plants, …

Evaluating Current And Future Range Limits Of An Endangered, Keystone Rodent (Dipodomys Ingens), Ivy V. Widick

Cal Poly Humboldt theses and projects

Climate is often considered the single most important factor limiting species’ ranges. Other factors, such as biotic interactions, are often assumed to be included via abiotic proxies. However, differential responses to climate change may decouple these relationships or lead to adaptation to novel environments. Accounting for competition and local adaptation should more accurately describe environmental factors influencing current distributions and increase the predictive accuracy of future distributions. Modeling the endangered giant kangaroo rat (Dipodomys ingens) is an excellent application of these model improvements, as the species range consists of geographically and genetically isolated populations experiencing disparate climatic change. …

The Effect Of Postural Alterations On Metabolic Cost In Running On Incline Slopes, Nikaela K. Hemminger

Cal Poly Humboldt theses and projects

In spite of an intuitive relationship between running technique and performance, the influence of specific techniques on metabolic cost remains unclear. While recent studies suggest that postural lean affects metabolic cost during level ground running, little information exists regarding the influence of postural lean on the metabolic cost of running on an incline slope. Purpose: This study sought to investigate the effect of postural lean on metabolic cost, kinematics, and muscle activation of running across a range of incline slopes. Methods: Sixteen healthy adult runners (21±2 years, 8M/8F) of different competitive standards participated in twelve running trials on a motorized …

Predictive Mapping Of Two Nearshore, Demersal Fish Species On Northern California Reefs Using Scuba-Based Visual Surveys And Remote Sensing, Christopher H. Teague

Cal Poly Humboldt theses and projects

California's shallow rocky reefs provide critical habitat for a diverse assemblage of fishes. Effective management strategies for these species require both accurate stock assessments as well as a spatially explicit understanding of the relationship between fishes and characteristics of their habitat. We used a generalized additive model framework to create spatially predictive maps of the abundance and biomass of two demersal fish species prevalent on northern California reefs: lingcod (Ophiodon elongatus) and kelp greenling (Hexagrammos decagrammus). These models incorporated data from SCUBA-based fish and habitat surveys at depths from 12-26 meters as well as measures of …

The Developmental Implications Of The Regulatory Relationship Between Cjun And Oct4 In Murine Embryonic Stem Cells, Rachel E. Brewer

Cal Poly Humboldt theses and projects

As cells transition from the point of fertilization through the process of embryonic development, many molecular changes occur that affect cell fate. At the blastocyst stage, the earliest distinction, two separate cell populations arise. The trophectoderm cells will generate all of the extraembryonic tissues while the inner cell mass will yield all of the embryonic tissues. These cells, which generate the organism, are termed pluripotent at this stage and found within the inner cell mass (ICM). A variety of genetic mechanisms that regulate this event have been characterized. Here, we examined the effect of cJun expression in regulating Oct4, a …

The Effects Of Prophylactic Ankle Bracing On Knee And Hip Mechanics In Basketball Players During Jump Landing, Riann Thayer

Cal Poly Humboldt theses and projects

Background: Many athletes of various sports have been required to wear ankle braces for prophylactic uses. Ankle braces have been shown to decrease range of motion in all directions, which means the main force absorption mechanism of the ankle may be inhibited. This decrease in force absorption at the ankle may increase the mechanical demands at the more proximal knee and hip joints. In this study, the change in knee, hip and lower back mechanics will be investigated to gain understanding as to whether bracing the ankle could create a higher injury potential. Methods: In this study, 12 intercollegiate basketball …

Productivity And Cost Of A Cut-To-Length Commercial Thinning Operation In A Northern California Redwood Forest, Kigwang Baek

Cal Poly Humboldt theses and projects

Cut-to-length (CTL) harvesting systems have recently been introduced to the redwood forests of California’s north coast. These machines are being used to commercially thin dense redwood (Sequoia sempervirens) stands which tend to form clumps of stems that vigorously sprout from stumps after a harvest. One of the challenges is to avoid damaging residual trees which can decrease productivity, increase costs, and lower the market value of trees. The goal of this study was to evaluate the productivity and costs associated with CTL systems used in a redwood forests and use that data to develop equations for predictions. Time …

Impacts On Soils And Residual Trees From Cut-To-Length Thinning Operations In California's Redwood Forests, Kyungrok Hwang

Cal Poly Humboldt theses and projects

In northern California, a cut-to-length (CTL) system was used for the first time to harvest young redwood forests (Sequoia sempervirens (Lamb. ex D. Don) Endl.). However, landowners and public agencies are concerned about the potential negative impacts of CTL logging to soils and residual trees since the extent and amount of CTL impacts are unknown in these forests. This study was designed to (1) determine soil physical property using bulk density (BD) and hydraulic conductivity (HC) (2) examine the characteristics of stand damage after CTL harvesting, and (3) compare the scar size differences between tree growing patterns (individuals vs. …

Test Of Bpa's Estrogenic Effects On Brain Aromatase Expression, Neural Activity, And Locomotive Behavior In Zebrafish Larvae, Ryan J. Mcauley

Cal Poly Humboldt theses and projects

Bisphenol A (BPA) is a well-known endocrine disrupting chemical that mimics the effects of estrogens. Aromatase B (Cyp19a1b) is a brain-specific enzyme that converts testosterone to estrogen and is highly upregulated in response to estrogen receptor activation localized to radial glial cells. During embryonic zebrafish development, there is a small window of time denoted by an increase in neurogenesis and estrogen receptor activity. Previous studies have demonstrated that a low dose BPA exposure (0.1µM) during this window causes hyperlocomotion in larval zebrafish, yet no further explanation for this behavior change has been described. The purpose of this study was to …

Hunting Habitat Use And Selection Patterns Of Barn Owl (Tyto Alba) In The Urban-Agricultural Setting Of A Prominent Wine Grape Growing Region Of California, Xeronimo A. Castaneda

Cal Poly Humboldt theses and projects

Large scale conversion of uncultivated land to agriculture threatens wildlife and can diminish ecosystem services provided by nature. Understanding how wildlife provision ecosystem services may incentivize wildlife conservation in agricultural landscapes. Attracting barn owls (Tyto alba) to nest on farms for pest management has been documented worldwide, but has not been thoroughly evaluated in vineyard agroecosystems. Napa Valley, California is a renowned winegrape growing region, and viticulturists encourage barn owl occupancy to help minimize plant damage from pocket gophers (Thomomys bottae) and voles (Microtus spp.). This study aimed to establish a basis for revealing the …

Legacies Of Industrial Contamination: Voices Of Resistance In White Lake, Michigan, Elizabeth A. Revord

Cal Poly Humboldt theses and projects

This research presents a case study of resistance to contamination from three large chemical plants by activists in the communities of Montague and Whitehall located on White Lake, Michigan. Although clean-up efforts have met state and federal guidelines for brownfield and Superfund sites, the people and community of White Lake have continued to be vigilant regarding environmental protection and harbor many concerns regarding their future and redevelopment of sites that are likely still contaminated.

The connection to place and sense of community that the residents of White Lake honor is the foundation of their resistance. Using data collected from semi-structured …

The Effects Of Forest Degradation On Dna Methylation In Central African Songbirds, Andrew K. Wiegardt

Cal Poly Humboldt theses and projects

Environmentally-induced stress can initiate a molecular response through DNA methylation, which can alter gene expression, thereby serving as a mechanism allowing individuals to acclimate to a changing environment within their lifetime. In addition to DNA methylation, the production and release of corticosterone is a physiological mechanism by which birds can cope with acute environmental stressors. To assess how environmental stress impacted DNA methylation and corticosterone, I collected blood and feather samples from three understory avian species (Alethe castanea, Bleda notatus and Pseudalethe poliocephala), along a disturbance gradient in the lowland Guinean rainforest adjacent to the village of …

Sex-Specific Habitat Selection Of Rough-Legged Hawks (Buteo Lagopus) Wintering In Western North America, Genevieve Christa Rozhon

Cal Poly Humboldt theses and projects

The rough-legged hawk (Buteo lagopus sanctijohannis) is one of the most under-studied raptor species in North America. As a species that exhibits reversed sexual dimorphism, sex-specific habitat preferences may exist. To investigate rough-legged hawk sex-specific habitat selection preferences, we equipped 17 rough-legged hawks (n = eight females, nine males) with GPS backpacks on their wintering grounds (n = six study areas) during the winter months of 2014 and 2015 in five states in western North America. I analyzed rough-legged hawk habitat selection in relation to sex at four spatial scales: nocturnal roosting site, 50% core range, 95% winter …

The Influence Of Microclimate And Local Adaptation For A Climate-Sensitive Species (Aplodontia Rufa), Jennie K. Jones Scherbinski

Cal Poly Humboldt theses and projects

Climate change models and analyses predict a disproportionate impact on climatically sensitive species such as the mountain beaver (Aplodontia rufa). Mountain beavers have physiological constraints that limit their distribution to cool, moist climates. While mountain beavers have persisted through past periods of climate change, increasing temperature since the last glacial maximum is believed to have had a strong influence in reducing their range. This is particularly true for the Point Arena subspecies (A. r. nigra, “PAMB”), found towards the southwestern edge of their range on the coast of California. Here, I examined the climatic niche of …

A Comparison Of Community Structure In Regulated And Unregulated Reaches In The Upper Eel River, California, Lara Stephanie Jansen

Cal Poly Humboldt theses and projects

Flow regulation of rivers by impoundments and diversions can reduce hydrological variability. As a result, densities of algae and benthic macroinvertebrates often increase, but many sensitive taxa are lost, causing shifts across the food web. In Northern California, dams that reduce winter peak floods can result in the primary consumer community becoming dominated by grazers that are relatively invulnerable to predation, which can reduce the amount of energy transferred up the trophic levels. The steeper slope of the spring hydrograph recession limb downstream of a dam can also greatly impact instream diversity of periphyton, invertebrates and fish. The dam and …

Effects Of Manual And Mechanical Ammophila Arenaria Removal Techniques On Coastal Dune Plant Communities And Dune Morphology, Monique R. Silva Crossman

Cal Poly Humboldt theses and projects

The removal of invasive species as part of the restoration process can allow natives organisms to rebound. An ecosystem that incurs damages from invasive species is coastal sand dunes, which are dynamic systems. Some coastal sand dunes on the west coast of the United States have been invaded by Ammophila arenaria. The invasive grass, A. arenaria, is thought to alter and stabilize foredune morphology and reduce populations of native species. The objectives of my research are to examine the effects that manual and mechanical A. arenaria removal techniques have on coastal sand dune morphology and vegetative cover over time. …

Characterizing Habitat Preference In Three Nearshore Reef-Associated Fishes Through Collaborative Research, Public Data, And Open Source Software, Ian D. Kelmartin

Cal Poly Humboldt theses and projects

Black rockfish (Sebastes melanops), canary rockfish (S. pinniger), and lingcod (Ophidion elongatus) are important species in Northern California’s nearshore recreational and commercial fisheries. These species are associated with nearshore rocky reefs and are among a suite of species intended to benefit from the establishment of the marine protected area (MPA) network along the Northern California Coast in 2012.

Many aspects of the North Coast’s nearshore ecosystem remain poorly studied, including the spatial distribution and habitat associations of nearshore fish species. This study used data collected from Cape Mendocino State Marine Reserve (SMR), Ten Mile …

Changes In Demography, Distribution, And Diet In Garter Snakes Following Eradication Of A Non-Native Prey Subsidy, Justin A. Demianew Mr.

Cal Poly Humboldt theses and projects

Interactions between non-native and native consumers are often complex and cryptic. I shed light on relationships between non-native brook trout (Salvelinus fontinalis), native amphibians, their shared predator (aquatic garter snake; Thamnophis atratus) and a sympatric amphibian specialist (common garter snake; T. sirtalis) using a treatment-control removal experiment in a sub-alpine system of northern California. Eradication of non-native S. fontinalis resulted in an immediate decrease in T. atratus abundance and survival, whereas their abundance increased in concert with T. sirtalis in an adjacent control basin. Additionally, T. atratus body condition decreased substantially during this time, despite their …

Evaluating Habitat Selection Models To Improve Site Selection In A Population Monitoring Program For Townsend's Big-Eared Bats (Corynorhinus Townsendii), Katrina J. Smith

Cal Poly Humboldt theses and projects

Winter roost (hibernacula) surveys offer a unique opportunity to monitor Townsend’s big-eared bats (Corynorhinus townsendii) while the population is generally closed, using a simple count method to census the population. Existing knowledge of C. townsendii hibernacula facilitates long-term population trend analysis but improving the accuracy of trend estimates requires identification of additional hibernacula to increase the proportion of the population monitored. Over 800 caves are known within Lava Beds National Monument; 322 of these have never been surveyed in the winter and could potentially hold a substantial portion of the C. townsendii population currently missing from the annual …

Export Of Invertebrate Drift From Fishless Headwater Streams, Jonathan M. Hollis

Cal Poly Humboldt theses and projects

An understanding of ecological linkages between headwater systems and downstream habitats is needed to enhance management practices for aquatic conservation. I quantified and described the export of invertebrate drift from fishless headwater streams to assess its potential importance to downstream populations of coastal cutthroat trout (Oncorhynchus clarki clarki) in the lower Klamath River in northern California. From June 2015 through April 2016, I sampled invertebrate drift in six fishless headwaters in the sub-basins of Tectah, Ah Pah, and Tarup creeks. Concurrently, I collected invertebrate drift and trout diet samples from adjoining fish-bearing streams. Drift export rates were lowest …

Implications Of Unmanned Aircraft Systems And Sense Of Place: A Case Study In The Mono Basin, Sara Elizabeth Matthews

Cal Poly Humboldt theses and projects

This paper contributes to an understanding of the social implications of using UAS in natural resource areas; specifically, the ways in which these tools impact human constructed sense of place. This paper draws on in-depth interviews and document analysis to (a) develop an understanding of place meanings held among Mono Basin stakeholders and (b) define the ways in which increased UAS presence may interact with these visions of place.

In short, this research shows that sense of place in this rural area is influential in the way that UAS are received by local stakeholders. The changing nature of place meanings …

The Effects Of Increased Camp Levels On Neuronal Differentiation In Murine Embryonic Stem Cells, And The Creation Of A Crispr-Induced C.1252c>T Point Mutation In The Adcy5 Gene, Elizabeth Zepeda

Cal Poly Humboldt theses and projects

ADCY5-related dyskinesia is a rare movement disorder with early onset in childhood and adolescence. Previous studies linked this disease to various point mutations in the ADCY5 gene. Recent studies show that two of the point mutations cause an increase in cyclic adenosine monophosphate (cAMP) levels. However, it remains unknown how increased levels of cAMP result in the phenotypes associated with this disease. My study examines the effects of increased cAMP levels on neuronal differentiation of mouse embryonic stem cells (mESCs). My experiments demonstrated successful differentiation of mESCs into the dopaminergic neuronal lineage, indicated by the presence of Tuj 1 (a …

Changing Parental Perceptions Of Children With Disabilities Physical Capability In Physical Activity Through A Family Fitness Program, Katelyn R. A. Knupper

Cal Poly Humboldt theses and projects

Children with disabilities are not participating in enough physical activity to meet the recommendations for health benefits. Parental perceptions of their child’s physical competence has a role in influencing physical activity levels. Parental perceptions can be improved through observations of their children in successful physical situations. Therefore, the purpose of this study was to analyze change in parental perceptions of their child’s physical competence after participating in a family-centered physical activity program. Five parents with a child aged six to 21 years with a disability participated in this study. Parental perceptions were assessed with the Perceived Competence Scale for Children, …