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Articles 1 - 30 of 40
Full-Text Articles in Physical Sciences and Mathematics
Quantifying Channel Change Following Post-Fire Debris Flows In A Steep, Coastal Stream, Big Sur, California, Telemak Olsen
Quantifying Channel Change Following Post-Fire Debris Flows In A Steep, Coastal Stream, Big Sur, California, Telemak Olsen
WWU Graduate School Collection
Debris flows commonly occur following wildfire in steep landscapes, introducing large volumes of sediment to downstream fluvial systems. Fire-related sediment supply perturbations impact channel morphology, and importantly, fragile aquatic and riparian ecosystems downstream of disturbance. The Big Creek watershed drains 57 km2 of steep chaparral and coast redwood forest along California’s Central Coast. Streams in the Big Creek watershed typically exhibit step-pool/cascade morphology and serve as vital spawning habitat for anadromous Steelhead Trout (Oncorhynchus mykiss). In 2020, 97% of the Big Creek watershed burned in the Dolan Wildfire. In January 2021, an atmospheric river event triggered a series of …
A Mixed-Methods Study Of Geoscience Identity, Race/Ethnicity, And Gender In Senior Undergraduate Geoscience Majors, Willa Rowan
A Mixed-Methods Study Of Geoscience Identity, Race/Ethnicity, And Gender In Senior Undergraduate Geoscience Majors, Willa Rowan
WWU Graduate School Collection
I conducted a mixed methods study of geoscience identity in undergraduate students to examine the cultural and social aspects of geoscience degree programs. White students are overrepresented in geoscience, and a priority of anti-racism efforts in the field is listening to the experiences of students who are Black, Indigenous, or people of color (BIPOC) to better inform equity and inclusion goals. Structural racism in geoscience pushes BIPOC students out of the field, and it can be better understood by studying socially constructed aspects of learning such as geoscience identity. This study is the first to measure geoscience identity with a …
U-Pb Zircon Geochronology And Structure Of Regional Blueschist Units In The Easton Metamorphic Suite, Northwest Cascades, Wa, Katherine Lang
U-Pb Zircon Geochronology And Structure Of Regional Blueschist Units In The Easton Metamorphic Suite, Northwest Cascades, Wa, Katherine Lang
WWU Graduate School Collection
The Easton metamorphic suite of the Northwest Cascades Thrust System (NWCS) is a well-preserved subduction accretion complex in Washington State. The regional blueschist units of the Easton metamorphic suite include the Mt. Josephine semi-schist, Darrington Phyllite, and Shuksan greenschist/blueschist and all are interpreted to have accreted after the onset of Jurassic subduction beneath North America. This study uses zircon U-Pb geochronology, structure, and field observations to test the regional correlations between units in the Easton metamorphic suite and address models for the timing of subduction accretion along the North American margin in the Late Jurassic – Early Cretaceous. The results …
Generations Of Stewards: Re-Indigenizing Youth Leadership, Learning, And Conservation Education, Drew Slaney
Generations Of Stewards: Re-Indigenizing Youth Leadership, Learning, And Conservation Education, Drew Slaney
WWU Graduate School Collection
My thesis is an exploratory case study into epistemologies (or worldviews) supported by organizations and agencies that develop outdoor conservation and education programs for Native youth called Native Youth Stewardship Programs (NYSPs). This subject relies on the content developed by Medin and Bang (2014) who state that an under-representation of Indigenous peoples in Science, Technology, Engineering, and Mathematics (STEM) fields is largely the result of epistemological conflicts between educators and Indigenous students. I hypothesize that there is a considerable epistemological difference between the conservation entities developing programs to engage Native youth. These differences may create significant barriers with youth recruitment, …
Evaluating Leaf Trait Variation In High Elevation Bristlecone Pine (Pinus Longaeva) Under Increasing Water Stress: Insights From Needle Length, Stomatal Density, And Cambial Growth, Audrey Salerno
WWU Graduate School Collection
Increasing aridification caused by climate change is altering growth patterns in trees. There is revived attention on how foliar traits respond to climate and the relationship of these traits to ring width. Bristlecone pine (Pinus longaeva, DK Bailey), a long-lived conifer found at high elevations in the cool and dry intermountain west of America, is used in paleoclimate reconstructions by measurement of their annually resolvable tree rings. The species also has annually datable needles retained on their branches for an average of 45 years making it the ideal subject for research on foliar trait and growth relationships under …
Contaminants Of Emerging Concern In Puget Sound: Screening, Prioritization, And Estrogenic Mixture Response Assessment, Maya Faber
WWU Graduate School Collection
Contaminants of emerging concern (CECs) are chemicals used in daily life, such as pharmaceuticals, personal hygiene products, steroids, pesticides, and flame retardants. The environmental occurrence and toxicology of CECs are poorly characterized, and they are generally unregulated. Traditional toxicological approaches rely on in vivo methods to test whole organisms for apical endpoints, including survival, reproduction, and growth. This is time-consuming and costly, both financially and in terms of laboratory animal well-being, limiting ecotoxicological data for CECs. To overcome this challenge, we are utilizing alternative approaches, including New Approach Methodologies (NAMs), to perform a screening-level evaluation of CECs present in Puget …
Trophic Transfer Of Metals From Seaweed To Shellfish In An Aquaculture System, Sophia Boyd
Trophic Transfer Of Metals From Seaweed To Shellfish In An Aquaculture System, Sophia Boyd
WWU Graduate School Collection
Seafood, including fish, shellfish, and seaweed, are an important source of nutrients that could meet some of the increasing demand for food globally. In addition to nutrients, chemical contaminants can also be acquired from the environment by primary producers. Seaweeds take up a variety of inorganic and organic contaminants, including metals, that may pose risks to human health. Through trophic transfer, organisms can accumulate elevated levels of contaminants from consuming lower trophic-level organisms. Since particulate organic matter, including seaweed detritus, is a food source for filter-feeding bivalves, contaminants present in seaweed could transfer to shellfish via ingestion. The purpose of …
Investigating Kīlauea’S 2018 Offshore Lava Emplacement Through Hydroacoustic Data, Olana Costa
Investigating Kīlauea’S 2018 Offshore Lava Emplacement Through Hydroacoustic Data, Olana Costa
WWU Graduate School Collection
The 2018 eruption of Kīlauea Volcano produced an unprecedented volume of lava, creating 3.5 km2 of new land on Hawai`i’s Big Island (Soule et al., 2021). Lava expelled from the Ahu`aila`au vent (originally called Fissure 8) traveled ~13 km to where it entered the ocean. Over half of the lava erupted in 2018 was emplaced offshore where it produced four new submarine lava deltas (Soule et al., 2021). In response to the eruption, a network of 12 ocean-bottom seismometers (OBS) with attached hydrophones was deployed on Kīlauea’s submarine south flank. Ten of the instruments successfully recorded data from July …
Visual Characteristics Of Walleye Pollock And Chinook Salmon: Modeling Theoretical Visual Space And Target Contrast Of Trawling Materials In The Bering Sea, Rebecca Haehn
WWU Graduate School Collection
Walleye pollock (Gadus chalcogrammus) and Chinook salmon (Oncorhynchus tshawytscha) are economic and cultural resources in Alaska. Chinook salmon bycatch is a large concern within the pollock fishery. Current strategies to reduce salmon bycatch include modifying trawl gear by implementing artificial light near or on escapement panels to increase salmon escapement. The visual characteristics of pollock and Chinook salmon were investigated to understand the perception of trawl gear. The visual pigments of each species were measured using microspectrophotometry (MSP). Pollock were dichromats with spectral sensitivity ranging from 449nm–518 nm and Chinook salmon were trichromats with sensitivity ranging …
Reconstructing Wildfire Regime During The Warm Paleocene-Eocene Climate Using Molecular Biomarkers From The Chuckanut Formation In Northwest Washington, U.S.A., Alexandra Elise Thompson
Reconstructing Wildfire Regime During The Warm Paleocene-Eocene Climate Using Molecular Biomarkers From The Chuckanut Formation In Northwest Washington, U.S.A., Alexandra Elise Thompson
WWU Graduate School Collection
Wildfires are expected to increase in frequency and severity as climate changes in the Pacific Northwest of North America. To better understand the effect of warming climate on wildfire regimes, I present the first reconstruction of past wildfire frequency and severity during the Paleocene-Eocene transition in northwest Washington state, U.S.A. The Chuckanut Formation is a late Paleocene to Eocene sedimentary unit with a robust paleobotanical record showing the existence of subtropical forests in northwest Washington during the Paleocene, transitioning to a relatively cooler Eocene, dominated by temperate mixed forests. Geochemical records of environmental change coinciding with Paleocene-Eocene climatic change in …
Does Sediment Supply Impact The Threshold For Initial Sediment Motion In Natural, Gravel Bedded Streams?, Emily Loucks
Does Sediment Supply Impact The Threshold For Initial Sediment Motion In Natural, Gravel Bedded Streams?, Emily Loucks
WWU Graduate School Collection
Sediment transport in river channels control channel morphology, streamflow, and benthic ecosystems. Predicting sediment transport rates through a channel is required for sediment management for stream restoration and aquatic habitat assessment. The critical Shields stress (τ*c), is a dimensionless parameter used in sediment transport models that characterizes the river bed surface shear stress required to initiate sediment motion. The τ*c is typically assumed constant in transport models, yet compilations of field data have shown that τ*c can vary wildly, causing sediment transport models to over- or under-predict fluxes by an order of magnitude or more. Understanding …
Distribution And Mixotrophy Of Cryptophyte Phytoplankton In The Northern Gulf Of Alaska, Megan O'Hara
Distribution And Mixotrophy Of Cryptophyte Phytoplankton In The Northern Gulf Of Alaska, Megan O'Hara
WWU Graduate School Collection
The Northern Gulf of Alaska (NGA) is a productive subarctic marine ecosystem that supports high abundances of plankton, fishes, seabirds, and mammals. Research has shown that this high productivity is primarily controlled by seasonal and spatial heterogeneity in the lower trophic level food web. Marine cryptophytes are a crucial, yet understudied, phytoplankton group in the NGA. Cryptophytes have the capacity for mixotrophy (acquiring energy through photosynthesis and feeding) which can improve trophic transfer efficiency, increase cellular growth rates, and improve retention of nutrients in the water column. Field samples collected in spring, summer, and fall 2021 surveyed the contribution of …
Impact Of Carbonaceous And Inorganic Nanomaterial Chemistry On Polymer Additive Release From Weathered Epoxy Composites, Haley Sefi-Cyr
Impact Of Carbonaceous And Inorganic Nanomaterial Chemistry On Polymer Additive Release From Weathered Epoxy Composites, Haley Sefi-Cyr
WWU Graduate School Collection
Nanomaterials (NMs) are small (< 100 nm), reactive, chemical species that can often be used as polymer fillers to improve mechanical strength and slow the degradation of polymer nanocomposites (PNCs). Polymers can undergo physical and chemical weathering which can result in increased release of polymer additives and non-polymerized monomers from the polymer matrix. This project aimed to study how NM chemistry and environmental weathering impacts the release and transformation of relevant PNC systems. Bisphenol A diglycidyl ether (BADGE) PNCs were synthesized containing titanium dioxide (TiO2), multi-walled carbon nanotubes (MWCNT), or graphene oxide (GO) NMs. These composites were subjected to either simulated or natural weathering conditions to quantify and characterize their capacity to leach endocrine-disrupting chemicals. Environmental variables, including temperature and ultra-violet (UV) light, were investigated for their impact on additive release. Fourier-transform infrared spectroscopy and Raman microscopy were used to characterize the PNCs which were leached in water for one to five days at 25, 45, or 65 °C. The degree of weathering also varied from no weathering, outdoor weathering, or simulated weathering using UV light. Leachates were analyzed using high-performance liquid chromatography quadrupole time-of-flight mass spectrometry to quantify release of bisphenol A (BPA), tert-butylphenol (TBP), and nonylphenol (NP). There were significant differences between NM types for PNCs weathered outdoors and leached at 25 °C for 24 h, however only TBP was detected in the leachate. When compared to the blank epoxy, GO PNCs leached significantly less in the UV and in May outdoor weathered experiments, MWCNT PNCs leached significantly less when weathered outdoors in May and June, and TiO2 PNCs leached significantly less when UV weathered. Each of the NMs has potential to decrease TBP release through sorption or photodegradation. The carbonaceous NMs (GO and MWCNT) may sorb TBP, inhibiting its release, while TiO2 may photodegrade TBP. The unweathered PNCs leached the most TBP, followed by UV weathered, and then outdoor weathered. A possible explanation for this is photodegradation of TBP by UV light in the UV- and outdoor-weathered experiments leading to removal of TBP prior to leaching. Future experiments should include additional sorption trials and long-term natural weathering with microplastic generation to further explore the release and degradation mechanisms.
Modeling 21st Century Peak Flows In The Nooksack River Basin In Northwestern Washington State Using Dynamically-Downscaled Global Climate Model Projections, Evan A. Paul
WWU Graduate School Collection
The Nooksack River in northwestern Washington State provides freshwater for agriculture, municipal, and industrial use and serves as a vital habitat for endangered salmon, a resource that is of cultural and economic importance to the Nooksack Indian Tribe and the surrounding region. As more landscape becomes exposed to rain rather than snow and heavy winter precipitation events intensify (i.e., atmospheric rivers), peak flows and sediment delivery to streams will increase due to rapid runoff, resulting in salmon habitat degradation and increased flood risk. Thus, anticipating the effect of climate change on peak flows is crucial for salmon habitat restoration efforts …
Paleomagnetic Determination Of Vertical Axis Block Rotation Near The Doty Fault In Southwestern Washington, Charles Linneman
Paleomagnetic Determination Of Vertical Axis Block Rotation Near The Doty Fault In Southwestern Washington, Charles Linneman
WWU Graduate School Collection
In this paper I present the results of paleomagnetically derived vertical axis rotations (VARs) of sites in two different flows of the Columbia River Basalt (CRB) – the 16 Ma Sentinel Bluffs member of the Grande Ronde flow and the 12 Ma Pomona Member of the Packsack Lookout – near the Doty fault in southwestern Washington. In two field seasons, I collected 99 cores from 14 sites, 11 in the Grande Ronde flow and three in the Pomona member flow. Of the 227 specimens that I demagnetized, 212 had well-defined magnetic directions. Positive fold and reversal tests results confirm the …
Coupling Unoccupied Aerial System Surveys And Elevation Measurements To Predict Native And Nonnative Eelgrass Cover In Padilla Bay, Jacqui Bergner
Coupling Unoccupied Aerial System Surveys And Elevation Measurements To Predict Native And Nonnative Eelgrass Cover In Padilla Bay, Jacqui Bergner
WWU Graduate School Collection
There are two primary species of eelgrass at the Padilla Bay National Estuarine Research Reserve, Zostera marina, a native eelgrass, and Zostera japonica, a nonnative. Unoccupied Aerial Systems (UAS) have been frequently used for eelgrass monitoring and mapping, especially for large populations like those in Padilla Bay. UAS imagery have resolutions of 10 cm or better and are much more cost and time effective than aerial surveys via traditional aircraft that may provide similar image resolutions. In this project, multispectral UAS imagery was coupled with a centimeter level Digital Elevation Model (DEM), created from Real Time Kinematic GNSS …
Regio- And Diastereoselective Samarium-Mediated Allylic Sulfone Reductions, Cody Schwans
Regio- And Diastereoselective Samarium-Mediated Allylic Sulfone Reductions, Cody Schwans
WWU Graduate School Collection
A series of allylic sulfones were synthesized containing a stereodirecting group and chelating element and subjected to samarium diiodide reductions in the presence of a proton donor. The resulting products could be obtained with high regioselectivity (no less than 95:5) and high diastereoselectivity (>10:1) that correlated with the size of the stereodirecting group. A mechanism is proposed that includes loss of the sulfone and formation of a chelated organosamarium intermediate followed by intramolecular protonation by a samarium-bound proton source. In this way, both the regioselectivity and absolute stereochemistry of the resulting products are explained.
The Economic And Emissions Reduction Potential Of Air Source Heat Pumps As A Replacement For Natural Gas And Electric Resistance Space Heating In The Contiguous United States, Joshua Schraer
WWU Graduate School Collection
It is widely believed that to reduce CO2 emissions the best strategy is to electrify everything, decarbonize the grid, and improve energy efficiency. This research looks specifically at the use of air source heat pumps (AHP) as a tool to reduce the CO2 emissions of heating energy in the residential sector. The landscape of residential energy use is complicated by a broad range of factors. We compare AHP, natural gas (NG), and electric resistance (ER) heating using data from energy prices, temperature, appliance efficiency, building efficiency and marginal emissions data from 2019 as well as modeled data of …
Activity And Selectivity Of Class B Sortase Enzymes, Sophie Jackson
Activity And Selectivity Of Class B Sortase Enzymes, Sophie Jackson
WWU Graduate School Collection
Gram-positive bacteria attach many proteins to their cell walls via sortase enzymes. Sortases are cysteine transpeptidases and are grouped into 6 classes, A-F. Sortase enzymes, particularly sortase A from Staphylococcus aureus, have been used extensively for in vitro protein ligations. Here, we investigate substrate-binding in sortase A from Streptococcus pyogenes. In addition, class B sortases are typically overlooked for research and development due to low in vitro activity and incomplete knowledge of substrate specificity. Here, we investigate the activity of class B sortases from Bacillus anthracis (baSrtB), Clostridioides difficile (cdSrtB), Listeria monocytogenes (lmSrtB), and Staphylococcus aureus (saSrtB). Of these, …
Impact Of Riverbank Lupine (Lupinus Rivularis) On Grand Fir (Abies Grandis) Ectomycorrhizal Symbioses, Andrew Labay
Impact Of Riverbank Lupine (Lupinus Rivularis) On Grand Fir (Abies Grandis) Ectomycorrhizal Symbioses, Andrew Labay
WWU Graduate School Collection
Lupine (Lupinus rivularis) is used in the revegetation of coarse sediments surrounding the Elwha basin in Washington State due to its ability to improve soil conditions. Previous research illustrated that seeding lupine with conifers increased growth and foliar nitrogen, however, decreased ectomycorrhizal (ECM) root colonization, an important symbiosis for conifers used in restoration. We hypothesized the observed decrease in ECM may be due to lupine increasing soil nitrogen, negating the need for a fungal symbiont. To investigate this, we explored the interaction between lupine and ECM colonization of grand fir (Abies grandis) in both a field …
Learning From Traditional Ecological Knowledge: Paralytic Shellfish Toxins In Butter Clams, Jackelyn Garcia
Learning From Traditional Ecological Knowledge: Paralytic Shellfish Toxins In Butter Clams, Jackelyn Garcia
WWU Graduate School Collection
Anthropogenic forcing of marine ecosystems is disproportionately impacting Indigenous food systems and the health of coastal Indigenous communities. With increasing harmful algal events, there is rising concern for access and health of coastal communities who rely on shellfish for commercial, food, subsistence, and ceremonial harvest. In the U.S West Coast, the dinoflagellate Alexandrium spp. may produce paralytic shellfish toxins, which can cause shellfish to become toxic and is of especial concern. While recent research has led to greater awareness of the risks associated with paralytic shellfish toxins (PSTs), the concern for harmful algae is not new. Coastal Indigenous communities have …
Glacial Loss And Threatened Fish: The Future Of Mount Rainier’S Cold-Water Bull Trout Habitats, Kathleen C. Ewen
Glacial Loss And Threatened Fish: The Future Of Mount Rainier’S Cold-Water Bull Trout Habitats, Kathleen C. Ewen
WWU Graduate School Collection
Glaciers play a key ecological role in the river systems that they support. Cold-water reaches supplied by glacial ice serve as critical habitats for aquatic organisms that rely on specific thermal ranges to survive. Federally threatened Bull Trout (Salvelinus confluentus) require very cold temperatures, like those found in glacial systems, to complete their life cycles. However, glaciers are retreating due to climate change and are expected to continue diminishing throughout this century. Decreased glacial extent could result in warmer stream temperatures downstream from glaciers and, depending on the magnitude of stream temperature increase, cold-water habitats relied upon by Bull Trout …
Structural, Mutational, And Kinetic Characterization Of Ura4, An Isocytosine Deaminase, Ashlee Hoffman
Structural, Mutational, And Kinetic Characterization Of Ura4, An Isocytosine Deaminase, Ashlee Hoffman
WWU Graduate School Collection
Cytosine Deaminases (CD) are a class of enzymes found in prokaryotes and fungi that have been studied in the past due to their ability to deaminate the prodrug 5-fluorocytosine (5-FC) producing 5-fluorouracil (5-FU). 5-FU is a common anti-cancer drug that can inhibit DNA synthesis leading to cancer cell death. 5-fluorocytosine can interact with digestive bacteria leading to unwanted side effects for cancer patients. Isocytosine Deaminases (ICD) are enzymes that are of interest in the treatment of cancers using Gene Directed Enzyme Prodrug Therapy (GDEPT). ICDs can deaminate the prodrug 5-fluoroisocytosine (5-FIC) also producing the drug 5-FU. 5-FIC will likely not …
Selectivity And Structure Of Chimeric Loop Swaps In Sh2 Domains, Sarah N. Smith
Selectivity And Structure Of Chimeric Loop Swaps In Sh2 Domains, Sarah N. Smith
WWU Graduate School Collection
SH2 (Src Homology 2) domains are protein domains that bind to phosphorylated tyrosine residues within cell signaling cascades. They have been found to play a role in certain cancers and immunological disorders. Despite their importance in cell signaling and medical relevance, the structural basis of the various selectivity classes of SH2 domains is only partially understood. Previous research found that the EF and BG loops of the domains contribute to forming the peptide binding pocket, and thus impact their selectivity. To further understand the role of these loops in selectivity, we engineered chimeric SH2 domains by swapping the EF and …
Development Of Silk Microparticles Capable Of Bioluminescence, Monique Berg
Development Of Silk Microparticles Capable Of Bioluminescence, Monique Berg
WWU Graduate School Collection
The use of silk microparticles (µPs) as drug delivery devices has gained attention due to slow degradation properties, mild preparation conditions, and advantageous biocompatibility. However, little research has been done on where these particles go once injected. To expand these studies, the goal for this work is to create bioluminescent silk µPs that can be tracked in vivo. Here several methods are demonstrated for preparing bioluminescent silk µPs containing Nanoluciferase (NLuc) and/or its substrate furimazine (FZ). In this study, silk µPs were formed using a salting-out procedure. The first method involved non-specific adsorption of NLuc and non-specific adsorption of FZ …
Stereoselective Synthesis Of (+)- And (-)-Cananodine, Haley Holliday
Stereoselective Synthesis Of (+)- And (-)-Cananodine, Haley Holliday
WWU Graduate School Collection
Natural products are an important class of molecules utilized in traditional medicine and inspire drug design in medicinal chemistry. Cananga odorata, a tree commonly known as ylang-ylang, contains natural products known to positively benefit health, and specifically promote liver health. One alkaloid isolated from Cananga odorata, cananodine, possesses cytotoxic properties, specifically against hepatocellular carcinoma (HCC). HCC is the most common type of liver cancer, with one million diagnoses projected by 2025 globally. Cananodine is a member of the guaipyridine alkaloid family, a class of compounds that feature a substituted pyridine bonded to a seven-membered ring. The first enantiomer …
Tuned Gold Layer Growth Onto Plasmonic Sensing Silver Nanocubes Via Synthetic Control Of Reduction Potentials., Nicolas Hall
Tuned Gold Layer Growth Onto Plasmonic Sensing Silver Nanocubes Via Synthetic Control Of Reduction Potentials., Nicolas Hall
WWU Graduate School Collection
Metallic nanoparticles (mNPs) are commonly employed as sensors and detection tools due to their unique plasmonic properties. Silver NPs exhibit these properties in heightened capacity in comparison to other metals. However, Ag NPs are susceptible to oxidation, degradation over time and are biotoxic. These issues are commonly addressed by creating Ag-alloy NPs or by adding additional layers to Ag NPs. This work improves upon these methods by focusing on the growth of an Au layer onto Ag nanocubes (AgNCs), resulting in a layered Au-Ag NC (Au@AgNC). The resulting morphology of these Au@AgNCs are dependent on the synthetic pathway taken and …
New Synthetic Methods Based On Silicon-Tethered Nucleophilic Addition Reactions, Alexie W. Clover
New Synthetic Methods Based On Silicon-Tethered Nucleophilic Addition Reactions, Alexie W. Clover
WWU Graduate School Collection
With the recent discovery of an iodine mediated rearrangement of diallylsilanes, we set out to investigate a similar fluorine mediated rearrangement, aimed at introducing a new method for synthesizing organofluorine compounds. Interest in incorporating fluorine into organic molecules has grown significantly in recent years, primarily for medicinal applications. Since certain fluorination methods require the use of mCPBA, a common epoxidizing reagent, control experiments were performed on the reaction of several diallylsilanes with mCPBA, anticipating that a competing epoxidation of the diallylsilanes might occur. It was found that the formation of the hydroxy ester occurred through a regioselective epoxide opening from …
Class A Sortases: Structures And Alternative Substrate Binding And Cleavage, Brandon Vogel
Class A Sortases: Structures And Alternative Substrate Binding And Cleavage, Brandon Vogel
WWU Graduate School Collection
Sortases, consisting of classes A-F, are cysteine transpeptidases found in the cell wall of Gram-positive bacteria. They play a crucial role in ligating proteins to the cell wall that are responsible for cell adhesion, immune evasion, host cell invasion, and nutrient acquisition through a transpeptidation reaction. Consequently, they are an attractive therapeutic target. Class A sortases are also utilized in protein engineering applications such as sortase-mediated ligations and sortagging. Despite extensive research in the past two decades, gaps persist in understanding how class A sortases recognize their substrates, primarily due to a lack of structural information on sortases non-covalently bound …
The Race Toward Carbon Neutral Ecotourism: Leveraging Life Cycle Analysis And Natural Climate Solutions For A Community Adventure Event, Ted Tarricone
The Race Toward Carbon Neutral Ecotourism: Leveraging Life Cycle Analysis And Natural Climate Solutions For A Community Adventure Event, Ted Tarricone
WWU Graduate School Collection
Global tourism is an interconnected framework of multiple industries that is influenced by and has impacts on economic, social, and environmental structures. Currently, tourism accounts for roughly 8% of global greenhouse gas emissions, which is expected to grow with industry expansion. To develop a scalable system for ecotourism assessment, emission reduction, and solutions to meet carbon neutrality, a small (n=3894 participants) adventure relay race named Ski to Sea in Bellingham, WA was studied. A life cycle analysis (LCA) conducted on the race showed similar proportional results to other tourism LCAs, where transport made up over 80% of the 325 tonnes …