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Full-Text Articles in Chemistry

Intra-Skeletal Variation In Stable Isotopes Through Non-Destructive Approaches: Applications Of The Patterns Of Skeletal Remodeling To Biological Anthropology, Armando Anzellini Dec 2022

Intra-Skeletal Variation In Stable Isotopes Through Non-Destructive Approaches: Applications Of The Patterns Of Skeletal Remodeling To Biological Anthropology, Armando Anzellini

Doctoral Dissertations

Stable isotope analysis is a well-established method in biological anthropology used to deliver data on residence, diet, and life history. Samples for these analyses are often collected from the diaphyses of long bones with an assumption of an expected rate of turnover between five and ten years, depending on the skeletal element. However, the biological foundations of this assumption are still uncertain, especially concerning the intra-skeletal and intra-element variation of isotopic signatures that may relate to patterns of remodeling. Exploring these gaps in intra-element isotopic variation requires fine-grained work using multiple bones from multiple individuals, but such work is limited …


A Study Of Red Snapper (Lutjanus Campechanus) Ecology In The Northern Gulf Of Mexico And The Effect Of Variable River Outflow Using Stable Isotope Analysis Of The Food Web And Eye Lenses, Caitlin C. Slife Aug 2022

A Study Of Red Snapper (Lutjanus Campechanus) Ecology In The Northern Gulf Of Mexico And The Effect Of Variable River Outflow Using Stable Isotope Analysis Of The Food Web And Eye Lenses, Caitlin C. Slife

Dissertations

In the Mississippi Bight and surrounding waters, river outflow impacts the basal resources of the Red Snapper food web, altering carbon sources and impacting prey and predator isotopes. In this study, the impact of riverine outflow on nutrients, particulate organic matter (POM), and physical water parameters on Red Snapper and their food web was analyzed using stable isotope and stomach content analysis over 5 years. The Mississippi, Pearl, Pascagoula, and Mobile rivers were included in the analysis of river impact. The Mississippi and Mobile rivers were found to significantly impact nutrients and POM in the region. River outflow was also …


Understanding Biogeochemical And Physical Controls On Methane Air-Sea Exchange Fluxes In The Pacific Ocean, Sarah Raney May 2022

Understanding Biogeochemical And Physical Controls On Methane Air-Sea Exchange Fluxes In The Pacific Ocean, Sarah Raney

Master's Theses

Methane and trace element samples were collected on GEOTRACES GP15 Pacific Meridional Transect (PMT) cruise conducted between the Aleutian Islands (57 °N) and Tahiti (20 °S) from September to November 2018. Uncertainty in methane air-sea exchange fluxes was determined using a propagation of errors approach. Fluxes ranged from -0.88 to 4.9 µmol CH4 m-2 d-1. Average CH4 flux along the Alaskan margin was 2.2 ± 2.9 µmol CH4 m-2 d-1. Methane fluxes decreased moving southward and increased to their open ocean maximum around 20 °N before declining in equatorial waters. Near …


The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth Jan 2022

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth

Williams Honors College, Honors Research Projects

It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H2O2 was the experimental factor to further test FeRB tolerance. H2O2 is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H2O2 concentrations were fed …