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Full-Text Articles in Physical Sciences and Mathematics

Data Mining Revision Controlled Document History Metadata For Automatic Classification, Dustin Maass Dec 2013

Data Mining Revision Controlled Document History Metadata For Automatic Classification, Dustin Maass

Theses and Dissertations

Version controlled documents provide a complete history of the changes to the document, including everything from what was changed to who made the change and much more. Through the use of cluster analysis and several sets of manipulated data, this research examines the revision history of Wikipedia in an attempt to find language-independent patterns that could assist in automatic page classification software. Utilizing two sample data sets and applying the aforementioned cluster analysis, no conclusive evidence was found that would indicate that such patterns exist. Our work on the software, however, does provide a foundation for more possible types of …


Structure And Function Of Proteins Investigated By Crystallographic And Spectroscopic Time-Resolved Methods, Namrta Purwar Dec 2013

Structure And Function Of Proteins Investigated By Crystallographic And Spectroscopic Time-Resolved Methods, Namrta Purwar

Theses and Dissertations

Biomolecules play an essential role in performing the necessary functions for life. The goal of this thesis is to contribute to an understanding of how biological systems work on the molecular level. We used two biological systems, beef liver catalase (BLC) and photoactive yellow protein (PYP). BLC is a metalloprotein that protects living cells from the harmful effects of reactive oxygen species by converting H2O2 into water and oxygen. By binding nitric oxide (NO) to the catalase, a complex was generated that mimics the Cat-H2O2 adduct, a crucial intermediate in the reaction promoted by the catalase. The Cat-NO complex is …


Wind Turbine Controls For Farm And Offshore Operation, Zhongzhou Yang Dec 2013

Wind Turbine Controls For Farm And Offshore Operation, Zhongzhou Yang

Theses and Dissertations

Development of advanced control techniques is a critical measure for reducing the cost of energy for wind power generation, in terms of both enhancing energy capture and reducing fatigue load. There are two remarkable trends for wind energy. First, more and more large wind farms are developed in order to reduce the unit-power cost in installation, operation, maintenance and transmission. Second, offshore wind energy has received significant attention when the scarcity of land resource has appeared to be a major bottleneck for next level of wind penetration, especially for Europe and Asia. This dissertation study investigates on several wind turbine …


Deformation And Fluid Interactions In The Mineral Fork Diamictites, Antelope Island, Utah, Kimberly Rose Johnson Dec 2013

Deformation And Fluid Interactions In The Mineral Fork Diamictites, Antelope Island, Utah, Kimberly Rose Johnson

Theses and Dissertations

ABSTRACT

DEFORMATION AND FLUID INTERACTIONS IN THE MINERAL FORK DIAMICTITES,

ANTELOPE ISLAND, UTAH

by

Kimberly R. Johnson

The University of Wisconsin-Milwaukee, 2013

Under the Supervision of Professor Dyanna Czeck

Diamictite from the Mineral Fork Formation on Antelope Island, Utah was deformed to various degrees on the footwall of the Willard Thrust Fault during the Sevier Orogeny. The diamictite contains clasts of differing strength resulting in quartzite clasts deformed the least, pink granitic clasts deformed to a greater degree, and softer green gneissic clasts deformed the most. The pink granitic and green gneissic clasts have similar compositions, but deform differently. This …


Transcending Microbial Source Tracking Techniques Across Geographic Borders: An Examination Of Human And Animal Microbiomes And The Integration Of Molecular Approaches In Pathogen Surveillance In Brazil And The United States, Amber Mae Koskey Dec 2013

Transcending Microbial Source Tracking Techniques Across Geographic Borders: An Examination Of Human And Animal Microbiomes And The Integration Of Molecular Approaches In Pathogen Surveillance In Brazil And The United States, Amber Mae Koskey

Theses and Dissertations

Waterborne illnesses, attributed to the ingestion or contact with contaminated water, present a significant global health concern. Surface water sources can be impacted by wide array of pollution inputs, but fecal pollution generates the most significant and acute threat to human health. Therefore, the detection of fecal bacteria in surface water sources remains an important public health objective. Current surface water monitoring employs the use of fecal indicator bacteria (FIB) including E. coli and enterococci as proxies for pathogenic organisms carried in fecal pollution. These traditional indicators, detected by culture-based microbiological methods, do not discriminate fecal sources from another. New …


Extracting The Structure And Conformations Of Biological Entities From Large Datasets, Ali Dashti Dec 2013

Extracting The Structure And Conformations Of Biological Entities From Large Datasets, Ali Dashti

Theses and Dissertations

In biology, structure determines function, which often proceeds via changes in conformation. Efficient means for determining structure exist, but mapping conformations continue to present a serious challenge. Single-particles approaches, such as cryogenic electron microscopy (cryo-EM) and emerging "diffract & destroy" X-ray techniques are, in principle, ideally positioned to overcome these challenges. But the algorithmic ability to extract information from large heterogeneous datasets consisting of "unsorted" snapshots - each emanating from an unknown orientation of an object in an unknown conformation - remains elusive.

It is the objective of this thesis to describe and validate a powerful suite of manifold-based algorithms …


A Two-Echelon Location-Inventory Model For A Multi-Product Donation-Demand Driven Industry, Milad Khajehnezhad Dec 2013

A Two-Echelon Location-Inventory Model For A Multi-Product Donation-Demand Driven Industry, Milad Khajehnezhad

Theses and Dissertations

This study involves a joint bi-echelon location inventory model for a donation-demand driven industry in which Distribution Centers (DC) and retailers (R) exist. In this model, we confine the variables of interest to include; coverage radius, service level, and multiple products. Each retailer has two classes of product flowing to and from its assigned DC i.e. surpluses and deliveries. The proposed model determines the number of DCs, DC locations, and assignments of retailers to those DCs so that the total annual cost including: facility location costs, transportation costs, and inventory costs are minimized. Due to the complexity of problem, the …


Evaluation Of Vdr-Coactivator Inhibitors Using Biochemical And Cell-Based Assays, Athena Marie Baranowski Dec 2013

Evaluation Of Vdr-Coactivator Inhibitors Using Biochemical And Cell-Based Assays, Athena Marie Baranowski

Theses and Dissertations

ABSTRACT

EVALUATION OF VDR–COACTIVATOR INHIBITORS USING BIOCHEMICAL AND CELL–BASED ASSAYS

by

Athena Baranowski

The University of Wisconsin–Milwaukee, 2013

Under the Supervision of Dr. Alexander Arnold

The vitamin D receptor (VDR) is a ligand–dependent transcription factor, which belongs to the nuclear receptor superfamily. VDR–mediated gene regulation is governed by coregulators (coactivators and corepressors). VDR coregulator binding inhibitors (CBIs), which were discovered using high throughput screening (HTS), were evaluated using cell–based assays and biochemical assays to determine their ability to inhibit the interaction between VDR and steroid receptor coactivator–2 (SRC–2). Determining their ability to inhibit the VDR–SRC–2 interaction can lead to the …


Sediment Microbial Fuel Cell As Sustainable Power Resource, Ananta Kothapalli Dec 2013

Sediment Microbial Fuel Cell As Sustainable Power Resource, Ananta Kothapalli

Theses and Dissertations

This research demonstrates that Ceratophyllum demersum a root less non vascular aquatic plant has negatively affected the power generation from a Sediment Microbial Fuel cell (SMFC). In SMFC the reduced organic matter in the sediment in water produces electrons, which reduces oxygen. Whereas in Plant SMFC continuous supply of organic matter to the anode is done by rhizodeposition (root exudates). Six SMFCs were run for more than 3 months to see the effect of plants, pH and temperature on power generation. Out of six only two SMFC showed stable data. The maximum power density 18 ± 1mW/m3 was generated from …


Extraction And Classification Of Drug-Drug Interaction From Biomedical Text Using A Two-Stage Classifier, Majid Rastegar-Mojarad Dec 2013

Extraction And Classification Of Drug-Drug Interaction From Biomedical Text Using A Two-Stage Classifier, Majid Rastegar-Mojarad

Theses and Dissertations

One of the critical causes of medical errors is Drug-Drug interaction (DDI), which occurs when one drug increases or decreases the effect of another drug. We propose a machine learning system to extract and classify drug-drug interactions from the biomedical literature, using the annotated corpus from the DDIExtraction-2013 shared task challenge. Our approach applies a two-stage classifier to handle the highly unbalanced class distribution in the corpus. The first stage is designed for binary classification of drug pairs as interacting or non-interacting, and the second stage for further classification of interacting pairs into one of four interacting types: advise, effect, …


A Crowdsourced Hail Dataset: Potential, Biases, And Inaccuracies, Joseph Robert Pehoski Dec 2013

A Crowdsourced Hail Dataset: Potential, Biases, And Inaccuracies, Joseph Robert Pehoski

Theses and Dissertations

Hail is a substantial severe weather hazard in the USA, with significant damage to property and

crops occurring annually. Traditional methods of forecasting hail size have limited accuracy, and despite

improvements in remote sensing of precipitation, the fall characteristics of hail make quantification of

hail imprecise. Research into hail is ongoing, but traditional hail datasets have known biases and low

spatiotemporal resolution. The increased usage of smartphones creates the opportunity to use a

crowdsourced dataset provided by the Precipitation Identification Near the Ground (PING) program, a

program developed by the National Severe Storms Laboratory. PING data is compared to approximate …


Beyond The Standard Model: Lhc Phenomenology, Cosmology From Post-Inflationary Sources, And Dark Matter Physics, Brian J. Vlcek Dec 2013

Beyond The Standard Model: Lhc Phenomenology, Cosmology From Post-Inflationary Sources, And Dark Matter Physics, Brian J. Vlcek

Theses and Dissertations

It is the goal of this dissertation to demonstrate that beyond the standard model, certain theories exist which solve conflicts between observation and theory -- conflicts such as massive neutrinos, dark matter, unstable Higgs vacuum, and recent Planck observations of excess relativistic degrees of freedom in the early universe. Theories explored include a D-brane inspired construct of U(3) × Sp(1) × U(1) × U(1) extension of the standard model, in which we demonstrate several possible observables that may be detected at the LHC, and an ability to stabilize the Higgs mechanism. The extended model can also explain recent Planck data …


Phylogeographic Inference Of Insular Mule Deer (Odocoileus Hemionus) Divergence In North America's Desert Southwest, Ona Alminas Dec 2013

Phylogeographic Inference Of Insular Mule Deer (Odocoileus Hemionus) Divergence In North America's Desert Southwest, Ona Alminas

Theses and Dissertations

Though mule deer (Odocoileus hemionus) persist in robust populations throughout most of their North American distribution, nearly 60% of their historic range in México has declined due to habitat loss and unregulated hunting. Two of the six subspecies inhabiting México's deserts and Baja California peninsula are of conservation concern, occurring on land bridge islands in the Pacific Ocean (O. h. cerrosensis on Cedros Island: threatened) and in the Sea of Cortés (O. h. sheldoni on Tiburón Island: endangered). Focusing on the desert southwest (n=449 deer), we obtained 1,611 bp of mtDNA sequence (control region: 583 bp; cytochrome b gene: 1,028 …


Landscape Ecological Analysis Of Patterns Influencing Bat Activity In Southeast Glacial Plains Of Wisconsin, Angela Leckie Jackson Dec 2013

Landscape Ecological Analysis Of Patterns Influencing Bat Activity In Southeast Glacial Plains Of Wisconsin, Angela Leckie Jackson

Theses and Dissertations

Nearly half of the world's bat species are threatened by anthropogenic land use. To contribute to the conservation of these cryptic mammals, it is imperative to understand bat habitat selection in human-dominated landscapes. Bat activity was calculated using active acoustic surveys conducted June and July for three years along river and lake transects in an agricultural matrix. Using multiple logistic regression and ANOVA regression tree analyses, I examined the relationship between bat activity of four species and habitat structure at multiple scales.

Aquatic features were determined to be the greatest predictor of bat activity with rivers supporting greater amount of …


Examining Spring And Autumn Phenology In A Temperate Deciduous Urban Woodlot, Rong Yu Dec 2013

Examining Spring And Autumn Phenology In A Temperate Deciduous Urban Woodlot, Rong Yu

Theses and Dissertations

This dissertation is an intensive phenological study in a temperate deciduous urban woodlot over six consecutive years (2007-2012). It explores three important topics related to spring and autumn phenology, as well as ground and remote sensing phenology. First, it examines key climatic factors influencing spring and autumn phenology by conducting phenological observations four days a week and recording daily microclimate measurements. Second, it investigates the differences in phenological responses between an urban woodlot and a rural forest by employing comparative basswood phenological data. Finally, it bridges ground visual phenology and remote sensing derived phenological changes by using the Normalized Difference …


Applying Computational Methods To Interpret Experimental Results In Tribology And Enantioselective Catalysis, Michael Garvey Dec 2013

Applying Computational Methods To Interpret Experimental Results In Tribology And Enantioselective Catalysis, Michael Garvey

Theses and Dissertations

Computational methods are rapidly becoming a mainstay in the field of chemistry. Advances in computational methods (both theory and implementation), increasing availability of computational resources and the advancement of parallel computing are some of the major forces driving this trend.

It is now possible to perform density functional theory (DFT) calculations with chemical accuracy for model systems that can be interrogated experimentally. This allows computational methods to supplement or complement experimental methods. There are even cases where DFT calculations can give insight into processes and interactions that cannot be interrogated directly by current experimental methods.

This work presents several examples …


An Experimental Investigation Characterizing The Tribological Performance Of Natural And Synthetic Biolubricants Composed Of Carboxylic Acids For Energy Conservation And Sustainability, Carlton Jonathan Reeves Dec 2013

An Experimental Investigation Characterizing The Tribological Performance Of Natural And Synthetic Biolubricants Composed Of Carboxylic Acids For Energy Conservation And Sustainability, Carlton Jonathan Reeves

Theses and Dissertations

Over the last several decades the lubrication industry has been striving to bring bio-based lubricants known as biolubricants to prominence. The reasons for the increased environmental initiatives are due to depletion of oil reserves, increases in oil price, stringent government regulations on petroleum-based oils, and most importantly, concerns for protecting the environment. With an estimated, 50% of all lubricants entering the environment and much of these being composed of toxic mineral oils, biolubricants have begun to witness a resurgence. This experimental investigation seeks to develop a new class of ecofriendly biolubricants that are less toxic to the environment, derived from …


Protein Association In Living Cells Using Fret Spectrometry: Application To G-Protein Coupled Receptors, Suparna Patowary Dec 2013

Protein Association In Living Cells Using Fret Spectrometry: Application To G-Protein Coupled Receptors, Suparna Patowary

Theses and Dissertations

Recent advancements in fluorescence microscopy coupled with newly developed fluorescent tags have transformed Fluorescence (Förster) Resonance Energy Transfer (FRET) into a powerful tool studying in vivo molecular interactions with improved spatial (angstrom) resolution. Though widely used to study protein-protein interactions, generalizing and testing the FRET theory for oligomeric complexes containing multiple donors and acceptors has only become possible in recent years. Therefore, many aspects of it are yet unexplored.

In this work, we tested the kinetic theory of FRET using linked fluorescent proteins located in the cytoplasm or at the plasma membrane. We used a novel method developed in our …


Mathematical Modeling Of Physiological Characteristics In Female Soccer Athletes, Thomas S. Goeppinger Aug 2013

Mathematical Modeling Of Physiological Characteristics In Female Soccer Athletes, Thomas S. Goeppinger

Theses and Dissertations

Intermittent sports create challenges regarding performance measurement. Quantification of various physiological characteristics can lead to increased performance and injury reduction throughout a season of competition. Currently, a variation of an athletes' heart rate is the primary physiological characteristic used for quantifying load on the athlete. With increasing technology, we have the ability to gather additional characteristics regarding the physicality of athletes during competition. This study statistically compares various models using these new characteristics as predictors to the athletes' lactate concentration in their blood. From this comparison, we determine which physiological characteristic(s) best represent the performance and fatigue of these athletes. …


Development Of Green Solvent Modified Zeolite (Gsmz) For The Removal Of Chemical Contaminants From Water, Elizabeth Stapleton Aug 2013

Development Of Green Solvent Modified Zeolite (Gsmz) For The Removal Of Chemical Contaminants From Water, Elizabeth Stapleton

Theses and Dissertations

Sorption represents an important strategy in the remediation of groundwater contamination. As a naturally-occurring mineral with large cation exchange capacity, zeolite is negatively charged and has been widely used as an inexpensive and effective sorbent for the removal of positively charged contaminants. The negative charges of zeolite, however, make it generally ineffective in the sorption of anionic contaminants such as chromate and arsenate. In order to improve the capacity for sorption of anionic species, the surface charge of the zeolite must be modified. Cationic surfactants can be used to alter the surface charge of the minerals so that the negatively …


Solving Virus Structures From Xfel Diffraction Patterns Of Random Particle Orientations Using Angular Correlations Of Intensities, Miraj Uddin Aug 2013

Solving Virus Structures From Xfel Diffraction Patterns Of Random Particle Orientations Using Angular Correlations Of Intensities, Miraj Uddin

Theses and Dissertations

The world's first x-ray free electron laser (XFEL), the Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator Center (SLAC) is now creating X-ray pulses not only of unprecendented brilliance; (a billion times brighter than the most powerful previous sources [8]) but also of ex- tremely short duration. Amongst the promised capabilities of this fourth- generation x-ray sources is the ability to record diffraction patterns from individual bio-molecules. The very first XFEL ''diffract and destroy'' exper- iments are being performed on relatively large objects such as viruses. To quote from Caspar and Klug[2], ''there are only a limited number …


The Effects Of School Type On Kindergarten Reading Achievement: Comparing Multiple Regression To Propensity Score Matching, Farrin Denise Bridgewater Aug 2013

The Effects Of School Type On Kindergarten Reading Achievement: Comparing Multiple Regression To Propensity Score Matching, Farrin Denise Bridgewater

Theses and Dissertations

BACKGROUND: Students taught at private schools by and large attain higher marks on reading achievement tests than do students taught at public schools. This difference is further aggravated by race, socioeconomic status, and reading ability at the entry of kindergarten.

PURPOSE: The goal of this nonexperimental study was to investigate whether students in either school type vary in reading achievement when they are measured on similar confounding variables (i.e., race, SES, and reading scores at the entrance of kindergarten).

METHODS: Propensity score matching, a method used to estimate causal treatment effect, was used to analyze the original sample of 12,250 …


Re-Examination Of Changes In Fluvial Stacking Pattern Across The P-T Boundary In The Central Transantarctic Mountains, Antarctica, Danielle Sieger Aug 2013

Re-Examination Of Changes In Fluvial Stacking Pattern Across The P-T Boundary In The Central Transantarctic Mountains, Antarctica, Danielle Sieger

Theses and Dissertations

A change in fluvial style and a change in the stacking pattern of fluvial channel sandstone bodies occur across the Buckley‒Fremouw formational contact in the central Transantarctic Mountains in Antarctica. Strata in the Buckley Formation are characterized by thick floodplain deposits in the Middle to Upper Permian Buckley Formation; whereas, stacked interconnected sandstone bodies occur in the Triassic Fremouw Formation (Barrett et al., 1986; Isbell & Macdonald, 1991a, 1991b; Collinson et al., 1994; Isbell et al., 1997; 2005). Such changes in fluvial stacking patterns have been attributed to changes in the creation of accommodation within basins due to changes in …


Evaluating The Summer Thermal Structure Of Southern Green Bay, Lake Michigan, Brice Grunert Aug 2013

Evaluating The Summer Thermal Structure Of Southern Green Bay, Lake Michigan, Brice Grunert

Theses and Dissertations

The summer thermal structure of southern Green Bay, Lake Michigan was evaluated using cable moorings equipped with thermistors and a near real-time coastal monitoring buoy. The net heat flux for the southern bay was calculated over the study period. Cold water intrusions from Lake Michigan were tracked using water temperature, with the path of these water masses tracking along the western shore of Green Bay. Water clarity was measured across the study region as kd. Surface diel warming was evaluated and compared with meteorological forcing variables and sensible and latent heat flux to determine the effect of water clarity on …


Bi- And Multi Level Game Theoretic Approaches In Mechanical Design, Ehsan Ghotbi Aug 2013

Bi- And Multi Level Game Theoretic Approaches In Mechanical Design, Ehsan Ghotbi

Theses and Dissertations

This dissertation presents a game theoretic approach to solve bi and multi-level optimization problems arising in mechanical design. Toward this end, Stackelberg (leader-follower), Nash, as well as cooperative game formulations are considered. To solve these problems numerically, a sensitivity based approach is developed in this dissertation. Although game theoretic methods have been used by several authors for solving multi-objective problems, numerical methods and the applications of extensive games to engineering design problems are very limited. This dissertation tries to fill this gap by developing the possible scenarios for multi-objective problems and develops new numerical approaches for solving them.

This dissertation …


Hydrogen Generation From Magnesium Hydride By Using Organic Acid, Yen-Hsi Ho Aug 2013

Hydrogen Generation From Magnesium Hydride By Using Organic Acid, Yen-Hsi Ho

Theses and Dissertations

In this paper, the hydrolysis of solid magnesium hydride has been studied with the high concentration of catalyst at the varying temperature. An organic acid (acetic acid, CH3COOH) has been chosen as the catalyst. The study has three objectives: first, using three different weights of MgH2 react with aqueous solution of acid for the hydrogen generation experiments. Secondly, utilizing acetic acid as the catalyst accelerates hydrogen generation. Third, emphasizing the combination of the three operating conditions (the weight of MgH2, the concentration of acetic acid, and the varying temperature) influence the amount of hydrogen generation. The experiments results show acetic …


I. Studies On The Organocatalytic Formation Of Quaternary Stereocenters. Ii. Studies On The Claisen Rearrangement As A Route To Quaternary Stereocenters. Iii. Asymmetric Synthesis Of Aldehydes Bearing Quaternary Carbon Centers Via The Decarboxylative Asymmetric Allylic Alkylation, Eduardo Alberch Aug 2013

I. Studies On The Organocatalytic Formation Of Quaternary Stereocenters. Ii. Studies On The Claisen Rearrangement As A Route To Quaternary Stereocenters. Iii. Asymmetric Synthesis Of Aldehydes Bearing Quaternary Carbon Centers Via The Decarboxylative Asymmetric Allylic Alkylation, Eduardo Alberch

Theses and Dissertations

The asymmetric synthesis of all carbon quaternary stereocenters poses a particular challenge due to the steric congestion inherent in the formation of such centers and has been the object of intense research these last 20-30 years. However, the amount of literature for the synthesis of aldehydes bearing quaternary stereocenters via enolate type chemistry is much more limited due to problems associated with the alkylation of such substrates including such types as Cannizzaro and Tischenko related reactions or self aldol condensations. The formation of aldehydes with quaternary stereocenters via use of enolate equivalents such as the DAAA (decarboxylative asymmetric allylic alkylation) …


The Boundedness Of Hausdorff Operators On Function Spaces, Xiaoying Lin Aug 2013

The Boundedness Of Hausdorff Operators On Function Spaces, Xiaoying Lin

Theses and Dissertations

For a fixed kernel function $\Phi$, the one dimensional Hausdorff operator is defined in the integral form by

\[

\hphi (f)(x)=\int_{0}^{\infty}\frac{\Phi(t)}{t}f(\frac{x}{t})\dt.

\]

By the Minkowski inequality, it is easy to check that the Hausdorff operator is bounded on the Lebesgue spaces $L^{p}$ when $p\geq 1$, with some size condition assumed on the kernel functions $\Phi$. However, people discovered that the above boundedness property is quite different on the Hardy space $H^{p}$ when $0

In this thesis, we first study the boundedness of $\hphi$ on the Hardy space $H^{1}$, and on the local Hardy space $h^{1}(\bbR)$. Our work shows that for …


Zinc Chemical Biology: The Pursuit Of The Intracellular Targets Of Zinquin, Andrew Nowakowski Aug 2013

Zinc Chemical Biology: The Pursuit Of The Intracellular Targets Of Zinquin, Andrew Nowakowski

Theses and Dissertations

Fluorescent sensors have been a main microscopic tools used to understand Zn2+ physiology on a cellular level. The use of the fluorescent Zn2+ sensor Zinquin (ZQ) and its analogues have revealed that transient Zn2+ is a chief component in a variety of biochemical pathways. Yet, little work has been performed to validate the exact targets of Zinquin in a cellular environment. The goals of this investigation are to determine the types of Zinquin reactions that take place in the cell as well as the identities of its cellular targets.

It has been hypothesized that Zinquin reacts with free Zn2+ within …


Phytoplankton Life History Events: Resting Stages And Physiological Cell Death, Christine R. Kozik Aug 2013

Phytoplankton Life History Events: Resting Stages And Physiological Cell Death, Christine R. Kozik

Theses and Dissertations

Understanding and predicting changes in phytoplankton populations requires knowledge of key life history processes such as recruitment from benthic resting stages and losses due to sedimentation and cell death. Currently, these processes are poorly understood in freshwater systems. Phytoplankton resting stage and cell death life history events were separately examined in two freshwater systems in Wisconsin, four northern lakes and an urban pond. In the norther lakes, sedimentation and benthic recruitment were examined using sediment and recruitment traps that were sampled weekly over two summers. Sedimentation and benthic recruitment contributed little to changes in standing crop chl a, but rather …