Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

USF Tampa Graduate Theses and Dissertations

Discipline
Keyword
Publication Year
File Type

Articles 781 - 810 of 1834

Full-Text Articles in Physical Sciences and Mathematics

Studies Of The Long-Term Change Of Global Mean And Regional Sea Surface Height, Yingli Zhu Apr 2019

Studies Of The Long-Term Change Of Global Mean And Regional Sea Surface Height, Yingli Zhu

USF Tampa Graduate Theses and Dissertations

Sea level change could have profound impacts on our society. We report here on three related sea level change problems. First, a variety of regression models have predicted different rates for global mean sea level rise over the past century. Some of these models are accelerating and others are not. We ask whether we can distinguish between these using a new nonparametric noise model that we have developed. Simulations show that we can, and further imply that GMSL is rising at an accelerating rate. Second, historical global mean sea level is reconstructed from tide gauges that are located along coastlines …


Volcanic Electrification: A Multiparametric Case Study Of Sakurajima Volcano, Japan, Cassandra M. Smith Apr 2019

Volcanic Electrification: A Multiparametric Case Study Of Sakurajima Volcano, Japan, Cassandra M. Smith

USF Tampa Graduate Theses and Dissertations

Electrical activity at volcanoes has been recently recognized as a potential new remote sensing technique for plume-forming eruptions. Volcanic electrical activity takes place in the conduit and plume and therefore has the benefit of being a direct indicator of surface activity. This is unlike seismic signals, which indicate magma/gas movement underground, and infrasound signals, which indicate a surface explosion but not necessarily the formation of an ash plume. There are two distinct types of volcanic electrical discharges: volcanic lightning and continual radio frequency (CRF) impulses. This dissertation explores the relationships between these two electrical signals and other commonly monitored volcanic …


Past Hydroclimate And Vegetation Variation In Romania Inferred From Isotopic Geochemistry And Pollen Of Cave Bat Guano, Daniel Martin Cleary Apr 2019

Past Hydroclimate And Vegetation Variation In Romania Inferred From Isotopic Geochemistry And Pollen Of Cave Bat Guano, Daniel Martin Cleary

USF Tampa Graduate Theses and Dissertations

While an abundance of paleo-records related to hydroclimate and vegetation exist in East-Central Europe, currently there is a scarcity of reconstructions that have the resolution to effectively capture the past 2000 years. A more complete understanding of this interval is important as it includes significant climatic events such as the Medieval Warm Period, Little Ice Age, and the post-industrial revolution human induced climate change. A solution to increasing our understanding of these events is the use of cave bat guano, a relatively underutilized source of climatic information.

Cave bat guano piles commonly have near annual deposition and in Europe can …


High-Resolution Investigation Of Event Driven Sedimentation: Response And Evolution Of The Deepwater Horizon Blowout In The Sedimentary System, Rebekka A. Larson Apr 2019

High-Resolution Investigation Of Event Driven Sedimentation: Response And Evolution Of The Deepwater Horizon Blowout In The Sedimentary System, Rebekka A. Larson

USF Tampa Graduate Theses and Dissertations

This Dissertation combines the investigation of the sedimentological impacts of the Deepwater Horizon (DwH) blowout event in the deep-sea benthos, with the refinement and advancement of methods and approaches for high-resolution investigations of events preserved in sedimentary records. An approach that combined, rapid collection of cores, a continued annual time series collection of cores, and high-resolution sampling and analyses, in particular short-lived Radioisotopes (SLRad), enabled the temporal resolution required to detect the sedimentary response to the short-duration DwH event, and evaluate post-event sedimentation patterns at a comparable time scale (months).

The collection of 179 sediment cores from 80 sites between …


Exploring Variations In Diet And Migration From Late Antiquity To The Early Medieval Period In The Veneto, Italy: A Biochemical Analysis, Ashley B. Maxwell Apr 2019

Exploring Variations In Diet And Migration From Late Antiquity To The Early Medieval Period In The Veneto, Italy: A Biochemical Analysis, Ashley B. Maxwell

USF Tampa Graduate Theses and Dissertations

This project tests the hypothesis that the Langobard migration into the Roman/Byzantine Veneto (northeastern Italy) resulted in significant dietary changes from Late Antiquity (4-5th centuries AD) to the Early Medieval period (6-8th centuries AD). At the end of the Great Germanic Migrations in AD 568, Langobards from Pannonia entered and occupied two-thirds of the Italian peninsula. It is unclear how large these migrations were, as historical documents exaggerate mass movements; however, conservative estimates suggest they made up 8% of the areas they occupied. The degree to which the Langobards influenced economic change and subsistence in this area is poorly understood. …


Estimating Coastal Water Turbidity Using Viirs Nighttime Measurement, Chih-Wei Huang Mar 2019

Estimating Coastal Water Turbidity Using Viirs Nighttime Measurement, Chih-Wei Huang

USF Tampa Graduate Theses and Dissertations

Coastal water turbidity is a key environmental factor that influences the relative clarity of the water, which therefore reduces sunlight penetration. The comprehensive spatial and temporal coverage of remote sensing allows mapping of water turbidity near the coast. Even in locations where time-consuming and expensive conventional turbidity monitoring programs exist, local technological limitations prevent complete coverage. Traditional optical satellite techniques using the visible band also have limitations in monitoring turbidity due to non-optimal observing conditions such as clouds, sun-glint, and thick aerosols. In this study, in order to complement the daytime satellite measurements, I used the data from Visible Infrared …


Robotic Motion Generation By Using Spatial-Temporal Patterns From Human Demonstrations, Yongqiang Huang Mar 2019

Robotic Motion Generation By Using Spatial-Temporal Patterns From Human Demonstrations, Yongqiang Huang

USF Tampa Graduate Theses and Dissertations

Robots excel in manufacturing facilities because the tasks are repetitive and do not change. However, when the tasks change, which happens in almost all tasks that humans perform daily, such as cutting, pouring, and grasping, etc., robots perform much worse. We aim at teaching robots to perform tasks that are subject to change using demonstrations collected from humans, a problem referred to as learning from demonstration (LfD).

LfD consists of two parts: the data of human demonstrations, and the algorithm that extracts knowledge from the data to perform the same motions. Similarly, this thesis is divided into two parts. The …


Force Feedback And Intelligent Workspace Selection For Legged Locomotion Over Uneven Terrain, John Rippetoe Mar 2019

Force Feedback And Intelligent Workspace Selection For Legged Locomotion Over Uneven Terrain, John Rippetoe

USF Tampa Graduate Theses and Dissertations

Legged robots present an incredible opportunity for humanity to conduct dangerous operations such as search and rescue, disaster recovery, and planetary exploration without ever placing themselves in harms way. The ability of a leg to more freely dictate its shape, orientation, and length gives it tremendous mobility and adaptability demanded of a system intended for operation outside of a controlled environment. However, one only need look at the average cat, dog, or friendly neighborhood squirrel to understand the immense gap that exists between what is possible of legged systems and their current set of capabilities.

Areas of study relevant to …


Full-Waveform Inversion Of Common-Offset Ground Penetrating Radar (Gpr) Data, Sajad Jazayeri Mar 2019

Full-Waveform Inversion Of Common-Offset Ground Penetrating Radar (Gpr) Data, Sajad Jazayeri

USF Tampa Graduate Theses and Dissertations

Maintenance of aging buried infrastructure and reinforced concrete are critical issues in the United States. Inexpensive non-destructive techniques for mapping and imaging infrastructure and defects are an integral component of maintenance. Ground penetrating radar (GPR) is a widely-used non-destructive tool for locating buried infrastructure and for imaging rebar and other features of interest to civil engineers. Conventional acquisition and interpretation of GPR profiles is based on the arrival times of strong reflected/diffracted returns, and qualitative interpretation of return amplitudes. Features are thereby generally well located, but their material properties are only qualitatively assessed. For example, in the typical imaging of …


Variations Of Sedimentary Biogenic Silica In The Gulf Of Mexico During The Deepwater Horizon And Ixtoc-I Oil Spill., Jong Jin Lee Mar 2019

Variations Of Sedimentary Biogenic Silica In The Gulf Of Mexico During The Deepwater Horizon And Ixtoc-I Oil Spill., Jong Jin Lee

USF Tampa Graduate Theses and Dissertations

The goal of this research is to understand the impacts of the 2010 Deepwater Horizon oil spill and the 1970-1980 IXTOC-I oil spill and other anthropogenic activity (e.g. dam construction) on surface water primary productivity by measuring sedimentary biogenic silica. It is known that sedimentary biogenic silica is distinct from mineral – bound silica, therefore it has been used as a proxy record for surface water primary productivity (e.g. diatom blooms). The Deepwater Horizon oil spill resulted in a widespread Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) event. The IXTOC-I oil spill was one of the largest oil spills …


Tip-Enhanced Nano-Optical Imaging Of Superacid Treated Bilayer Mos2-Ws2 2d Lateral Heterostructures, Amala Dixit Mar 2019

Tip-Enhanced Nano-Optical Imaging Of Superacid Treated Bilayer Mos2-Ws2 2d Lateral Heterostructures, Amala Dixit

USF Tampa Graduate Theses and Dissertations

Nanoscale optical characterization of two-dimensional (2D) materials and heterostructures is important for the design of novel optoelectronic flexible nano-devices. Nano-optical photoluminescence (PL) and Raman imaging of bilayer 2D materials has been a challenging problem due to weak signals. The exciton-dominated light emission of two-dimensional (2D) transition metal dichalcogenide (TMDC) materials is affected by the formation of defects and doping states. Previous studies have shown that chemical treatment modifies the defect and doping states of chemical vapor deposition (CVD)-grown monolayers of MoS2 and WS2, which provides a promising possibility for engineering the optoelectronic properties of these 2D TMDCs. …


Zooplankton Community Structure In The Ne Gulf Of Mexico: Impacts Of Environmental Variability And The Deepwater Horizon Oil Spill, Kate M. Dubickas Mar 2019

Zooplankton Community Structure In The Ne Gulf Of Mexico: Impacts Of Environmental Variability And The Deepwater Horizon Oil Spill, Kate M. Dubickas

USF Tampa Graduate Theses and Dissertations

In the northeastern Gulf of Mexico, relating changes in zooplankton communities to environmental factors is crucial to understanding the marine ecosystem and impacts of perturbations such as oil spills on marine ecosystems. Zooplankton samples were collected each year between 2005–2014 in spring and summer in the vicinity of the oil spill (Deepwater Horizon) that occurred in spring 2010. Zooplankton assemblages and environmental conditions significantly differed seasonally, driven by strong variations in zooplankton at continental shelf stations, and by environmental factors including Mississippi River discharge, wind direction, temperature, and chlorophyll concentrations. Total zooplankton abundances were greatest at shelf stations, intermediate at …


Species Abundance, Spatial And Vertical Distributionsof Large Heteropods (Pterotracheidae And Carinariidae)In The Northern Gulf Of Mexico, Kristine A. Clark Mar 2019

Species Abundance, Spatial And Vertical Distributionsof Large Heteropods (Pterotracheidae And Carinariidae)In The Northern Gulf Of Mexico, Kristine A. Clark

USF Tampa Graduate Theses and Dissertations

A description of species abundance, richness and distribution, and eye size of heteropod molluscs from the families Pterotracheidae and Carinariidae in the oligotrophic ecosystem of the northern Gulf of Mexico (GOM) is described based on discrete-depth sampling protocols. The collections were comprised from two midwater sampling programs conducted sequentially after the 2010 Deepwater Horizon oil spill (DWHOS): the Offshore Nekton Sampling and Analysis Program (ONSAP, 2011) and the Deep Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND, 2015-2018). Study materials from DEEPEND were collected during the initial five cruises of 2015-2017. These programs collected over 3,495 heteropods in two …


Conducting Polymer Based Gel Electrolytes For Ph Sensitivity, Aditya Jagannath Kashyap Mar 2019

Conducting Polymer Based Gel Electrolytes For Ph Sensitivity, Aditya Jagannath Kashyap

USF Tampa Graduate Theses and Dissertations

The evaluation of concentration of ions and molecules with the help of biosensors have been regarded as an emerging technology. Bio and chemical sensors have a variety of applications in the field of medicine, military, environmental and food industries alike. With an estimated investment growth of over 4.31% in the development of pH sensors in the next five year, the objective of a developing a robust measurement system is all the more required. The scope of this research is to evaluate the ability of conducting polymer-based gel electrolytes for pH sensitivity, as a function of the transistor characteristics using an …


Fish Communities On Natural And Artificial Reefs In The Eastern Gulf Of Mexico, Elizabeth C. Viau Mar 2019

Fish Communities On Natural And Artificial Reefs In The Eastern Gulf Of Mexico, Elizabeth C. Viau

USF Tampa Graduate Theses and Dissertations

Artificial reefs have been deployed throughout the world’s oceans to act as habitat and fishing enhancement tools. To expand current research on the role of artificial reefs in the marine community, ordination and multivariate regression methods were used here to analyze survey data of natural and artificial reefs. The reefs, located in the Northern Gulf of Mexico (NGOM) and on the West Florida Shelf (WFS), had been previously surveyed from 2004 to 2015 using remote operated vehicle and stationary video techniques. This study tested the hypothesis that similar functional roles are accounted for at both natural and artificial reef sites …


Water Scarcity In The Face Of Hurricanes: Improving The Resilience Of Potable Water Supplies In Selected Florida Counties, Fautemeh Sajadi Bami Mar 2019

Water Scarcity In The Face Of Hurricanes: Improving The Resilience Of Potable Water Supplies In Selected Florida Counties, Fautemeh Sajadi Bami

USF Tampa Graduate Theses and Dissertations

Severe storms can threaten the reliability and accessibility of drinking water supplies. The state of Florida is frequently impacted by hurricanes and is often struck more than once a year. An example of this can be found in 2017 when hurricanes Harvey, Irma, and Maria caused much damage. Compromised utilities, well contamination, and shortages in bottled water and ice are just some of the problems that may threaten peoples’ drinking water.

Faced with these issues, preparation and response efforts must be effective in order to promote human health. Recent events like Hurricane Irma caused shortages in potable water which suggest …


Complex Tripartite Hydro Politics Of River Ganges, Muttaki Bin Kamal Mar 2019

Complex Tripartite Hydro Politics Of River Ganges, Muttaki Bin Kamal

USF Tampa Graduate Theses and Dissertations

This paper studies if the Flagship Namami Gange program of Cleaning the river Ganges in India aligns with the transcendental discourse on the river. Web contents as Facebook, YouTube and Twitter along with Indian English daily newspaper reports are used here as the source of data. The study shows that the program aligns with the transcendental discourse on river Ganges as the Mother Goddess and reaching out to her devotees.


The Systems Of Post And Post Algebras: A Demonstration Of An Obvious Fact, Daviel Leyva Mar 2019

The Systems Of Post And Post Algebras: A Demonstration Of An Obvious Fact, Daviel Leyva

USF Tampa Graduate Theses and Dissertations

In 1942, Paul C. Rosenbloom put out a definition of a Post algebra after Emil L. Post published a collection of systems of many–valued logic. Post algebras became easier to handle following George Epstein’s alternative definition. As conceived by Rosenbloom, Post algebras were meant to capture the algebraic properties of Post’s systems; this fact was not verified by Rosenbloom nor Epstein and has been assumed by others in the field. In this thesis, the long–awaited demonstration of this oft–asserted assertion is given.

After an elemental history of many–valued logic and a review of basic Classical Propositional Logic, the systems given …


Storm Surge And Evacuations In Pinellas County, Christianne Pearce Mar 2019

Storm Surge And Evacuations In Pinellas County, Christianne Pearce

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to determine evacuation decisions of residents in Pinellas County, a vulnerable area in Florida, during Hurricane Irma in 2017, and whether those decisions will impact their future decisions to evacuate. This study also examines the resident’s perception of storm surge flooding during a hurricane. To understand evacuation decisions and storm surge perceptions a survey was conducted on residents in vulnerable areas of Pinellas County. The survey examined multiple aspects including the role of media, relationships, and sociodemographic status on decision making. Another aspect examined if their decision to evacuate for Hurricane Irma will impact …


Examining The Spatial And Temporal Variations In Co2 Partial Pressure In The Deep Vadose Zone Above Jinapsan Cave, Guam, Jamar Regis Mar 2019

Examining The Spatial And Temporal Variations In Co2 Partial Pressure In The Deep Vadose Zone Above Jinapsan Cave, Guam, Jamar Regis

USF Tampa Graduate Theses and Dissertations

Carbon dioxide is the primary driver of dissolution and precipitation reactions in epigene limestone caves. While much work has been conducted on CO2 dynamics involved in dissolution in the phreatic zone, less research has been conducted on vadose CO2 dynamics, especially in tropical caves developed in eogenetic limestones. In this study, we investigate spatial and temporal variation in pCO2 in the deep vadose zone of eogenetic limestone above Jinapsan Cave, located in northern Guam. Five years of carbonate chemistry data from three dripwater sites in Jinapsan Cave (Flatman, Station1, and Trinity) were used to model the theoretical pCO2 with which …


Analyses Of Unorthodox Overlapping Gene Segments In Oxytricha Trifallax, Shannon Stich Mar 2019

Analyses Of Unorthodox Overlapping Gene Segments In Oxytricha Trifallax, Shannon Stich

USF Tampa Graduate Theses and Dissertations

A ciliate is a phylum of protozoa that has two types of nuclei, macronuclei and micronuclei. There may be more than one of each type of nucleus in the organism [1]. The macronucleus is the structure where protein synthesis and cell metabolism occur [1]. The micronucleus stores genetic information and is mobilized during a sexual reproduction process called conjugation [1]. The somatic macronucleus (MAC) is developed from the germ-line micronucleus (MIC) through genome rearrangement during a sexual reproduction process called conjugation [6, 8]. Segments of the MIC that form the MAC during conjugation are called macronuclear destined sequences (MDSs) [8]. …


Dna Barcoding Of Fish Eggs In The Gulf Of Mexico, Makenzie Burrows Mar 2019

Dna Barcoding Of Fish Eggs In The Gulf Of Mexico, Makenzie Burrows

USF Tampa Graduate Theses and Dissertations

DNA barcoding of fish eggs is a relatively new technique that enables more accurate identification of early life stages of ecologically and economically important fish species. Using DNA barcoding of individual planktonic percomorph eggs, this thesis determines putative spawning locations of neritic and oceanic fish species in the Gulf of Mexico (GoM). Surveys at 40 stations in the Gulf of Mexico showed a clear delineation of spawning sites, with neritic fish eggs generally found on continental shelves, and oceanic fish eggs found at the surface of deeper waters. However, samples collected between Florida and Cuba revealed exceptions to this trend …


Assessing Paleo-Coastal Caves Evolution And Sea Level Changes In Mallorca: Results From Radiometric Dating Of Speleothems, Giuseppe Lucia Mar 2019

Assessing Paleo-Coastal Caves Evolution And Sea Level Changes In Mallorca: Results From Radiometric Dating Of Speleothems, Giuseppe Lucia

USF Tampa Graduate Theses and Dissertations

Sea level affects the littoral morphology and structure in different ways. In coastal karst basins, dissolutional and depositional processes are strictly related to sea level variation. A great variety of karst-related geomorphological features and cave deposits exist above, below, and at sea level, and are extremely useful to study past changes of relative sea level. Within these, vadose speleothems such as flowstones and stalagmite, can document unequivocal maximum sea level constraints as well as record phreatic phases of sea level rise. Here we present a series of geochronological data from the eastern Mallorca and show the implication of relative sea …


The Ability Of The U.S. Military’S Wbgt-Based Flag System To Recommend Safe Heat Stress Exposures, David R. Almario Mar 2019

The Ability Of The U.S. Military’S Wbgt-Based Flag System To Recommend Safe Heat Stress Exposures, David R. Almario

USF Tampa Graduate Theses and Dissertations

The U.S. military currently uses a flag system based on wet-bulb globe temperature (WBGT) and metabolic rate to recommend heat stress exposure limits. This paper addresses the ability of the flag system to recommend safe heat exposures in a non-military population.

Two progressive heat stress studies provided data on 528 observations of safe or unsafe exposures of 4 hours over a range of WBGT conditions and metabolic rates using 29 participants wearing woven cotton clothing. For the two studies, range of WBGT conditions was 25 to 42C, and the range of metabolic rates was 100 to 650 watts. These exposures …


Parallelization Of Genetic Algorithm To Solve Max-3sat Problem On Gpus, Prakruthi Shivram Mar 2019

Parallelization Of Genetic Algorithm To Solve Max-3sat Problem On Gpus, Prakruthi Shivram

USF Tampa Graduate Theses and Dissertations

There are many combinatorial optimization problems such as flow shop scheduling, quadraticassignment problem, traveling salesman problem, that are computationally intractable. Genetic Algorithm is a heuristic algorithm used to find an answer to combinatorial optimization problems. MAX-3SAT is an example of combinatorial optimization problem which has wide range of applications as many real world problems can be translated to MAX-3SAT problem. Genetic algorithms are suitable to solve MAX-3SAT problems but usually undergo premature convergence. To prevent this convergence and maintain diversity, one possible solution is to use large population size. This increases computation cost and time. Since Genetic Algorithms compute the …


An Efficient Run-Time Cfi Check For Embedded Processors To Detect And Prevent Control Flow Based Attacks, Srivarsha Polnati Mar 2019

An Efficient Run-Time Cfi Check For Embedded Processors To Detect And Prevent Control Flow Based Attacks, Srivarsha Polnati

USF Tampa Graduate Theses and Dissertations

A popular software attack on a program is by transferring the program control to malicious code inserted into the program. Control Flow Integrity (CFI) check has been proposed as a detection mechanism for control flow deviation. In the context of embedded processors, this thesis proposes a novel approach to implement CFI to detect and stall under a control flow attack. We exploit the unused bits in an instruction word to embed a label that can be used to check CFI during runtime. Given a control flow graph, we embed a unique label in each instruction in a basic block such …


Empirical Analysis Of A Cybersecurity Scoring System, Jaleel Ahmed Mar 2019

Empirical Analysis Of A Cybersecurity Scoring System, Jaleel Ahmed

USF Tampa Graduate Theses and Dissertations

In the field of cybersecurity, the top-level management make use of metrics to decide if the organization is doing well to protect itself from cyber attacks or is in tatters leaving itself susceptible against the vast threats looming around. Not only that but metrics are even used to measure the performance of the security team. The aim of this thesis is to show how economics is closely related to cybersecurity and how metrics play an important role in policy making of an organization. Furthermore, I scrutinize one of the leading security score providers for the way they detect botnet infection. …


Modeled Affinity Constants For Phosphorus Adsorption And Desorption Due To Saltwater Intrusion, Yasemin Taşcı Mar 2019

Modeled Affinity Constants For Phosphorus Adsorption And Desorption Due To Saltwater Intrusion, Yasemin Taşcı

USF Tampa Graduate Theses and Dissertations

It is important to understand the processes that regulate phosphorus (P) fluxes to coastal environments, because P is an important nutrient in coastal ecosystems. Phosphorus adsorbs to the surface of minerals in sediment and bedrock, and an influx of seawater can cause some of that P to desorb, raising the P concentration of ambient water. Although seawater-induced P desorption is thought to be an important source of P to coastal environments, the chemical reactions that underlie it have not been established. Previous work provides some relevant surface reactions and associated affinity constants between various aqueous P species and the surface …


Field Quantization For Radiative Decay Of Plasmons In Finite And Infinite Geometries, Maryam Bagherian Mar 2019

Field Quantization For Radiative Decay Of Plasmons In Finite And Infinite Geometries, Maryam Bagherian

USF Tampa Graduate Theses and Dissertations

We investigate field quantization in high-curvature geometries. The models and calculations can help with understanding the elastic and inelastic scattering of photons and electrons in nanostructures and probe-like metallic domains. The results find important applications in high-resolution photonic and electronic modalities of scanning probe microscopy, nano-optics, plasmonics, and quantum sensing.

Quasistatic formulation, leading to nonretarded quantities, is employed and justified on the basis of the nanoscale, here subwavelength, dimensions of the considered domains of interest.

Within the quasistatic framework, we represent the nanostructure material domains with frequency-dependent dielectric functions. Quantities associated with the normal modes of the electronic systems, the …


Regeneration Of Trace Metals During Phytoplankton Decay: An Experimental Study, Adrienne P. Hollister Mar 2019

Regeneration Of Trace Metals During Phytoplankton Decay: An Experimental Study, Adrienne P. Hollister

USF Tampa Graduate Theses and Dissertations

Trace metals act as important nutrients, and sometimes toxins, to phytoplankton and other marine microorganisms. When phytoplankton decay, the elements in their cells are released back into the water column through regeneration (also referred to as remineralization), one of the processes responsible for governing concentrations of dissolved trace metals and macronutrients in depth profiles. In order to experimentally study regeneration, controlled experimental incubations of mixed phytoplankton assemblages from the Gulf of Mexico (GoM) and monocultures of the diatom Pseudo-nitzschia dolorosa and the dinoflagellate Karenia brevis were placed in the dark and monitored as they decayed with naturally present bacteria. Over …