Digital Commons Network^™

Rates Of Carbonate Dissolution In Permeable Sediments Estimated From Porewater Profiles: The Role Of Sea Grasses, David J. Burdige, Richard C. Zimmerman, Xinping Hu

OES Faculty Publications

In this study we estimate sediment carbonate dissolution rates for sandy sea grass sediments on the Bahamas Bank using an inverse pore-water advection/diffusion/reaction model constrained by field observations. This model accounts for sea grass O₂ input to these sediments, and also parameterizes pore-water advection through these permeable sediments as a nonlocal exchange process. The resulting rates of carbonate dissolution are positively correlated with sea grass density, and are comparable with previous rate estimates for Florida Bay sediments. In contrast, the advective uptake of O₂ by these sediments decreased with increasing sea grass density. This suggests that the competing …

Radiocarbon Evidence For The Importance Of Surface Vegetation On Fermentation And Methanogenesis In Contrasting Types Of Boreal Peatlands, J. P. Chanton, P. H. Glaser, L. S. Chasar, David J. Burdige, M. E. Hines, D. I. Seigel, L. B. Tremblay, W. T. Cooper

OES Faculty Publications

We found a consistent distribution pattern for radiocarbon in dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and methane replicated across spatial and temporal scales in northern peatlands from Minnesota to Alaska. The ¹⁴C content of DOC is relatively modern throughout the peat column, to depths of 3 m. In sedge-dominated peatlands, the ¹⁴C contents of the products of respiration, CH₄ and DIC, are essentially the same and are similar to that of DOC. In Sphagnum- and woody plant-dominated peatlands with few sedges, however, the respiration products are similar but intermediate between the ¹⁴C contents of …

Co2 Sensitivity Of Southern Ocean Phytoplankton, Philippe D. Tortell, Christopher D. Payne, Yingyu Li, Scarlett Trimborn, Bjorn Rost, Walker O. Smith, Christina Riesselman, Robert B. Dunbar, Peter Sedwick, Giacomo R. Ditullio

OES Faculty Publications

The Southern Ocean exerts a strong impact on marine biogeochemical cycles and global air-sea CO₂ fluxes. Over the coming century, large increases in surface ocean CO₂ levels, combined with increased upper water column temps. and stratification, are expected to diminish Southern Ocean CO₂ uptake. These effects could be significantly modulated by concomitant CO₂-dependent changes in the region's biol. carbon pump. Here we show that CO₂ concentrations affect the physiology, growth and species composition. of phytoplankton assemblages in the Ross Sea, Antarctica. Field results from in situ sampling and ship-board incubation experiments demonstrate that inorganic …

The Use Of Extractable Lipofuscin For Age Determination Of Crustaceans: Reply To Sheehy (2008), H. Rodger Harvey, David H. Secor, Se-Jong Ju

OES Faculty Publications

The heterogeneous mixture of metabolic by-products termed lipofuscin (LF) or age pigments has long been known to accumulate in post mitotic cells with increasing age. In crustaceans several approaches have been developed over the years to track LF accumulation and provide a proxy for chronological age. Histological approaches have been traditionally used for LF determination of crustaceans (e.g. Sheehy et al. 1994, Mar Biol 121:237-245), but over the last decade extraction approaches for neural tissues have been introduced (Ju et al. 1999, Mar Ecol Prog Ser 185:171-179) and tested (Ju et al. 2001, Mar Ecol Prog Ser 224:197-205; 2003, Fish …

Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins

OES Faculty Publications

We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO₂ levels. Rates of N₂ and CO₂ fixation and growth increased in step with increasing partial pressure of CO₂ (pCO₂), but only under Fe- replete conditions. N₂) and carbon fixation rates at 75 Pa CO₂ were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO_{2 …}

A Tribute To Peter George Brewer In Celebration Of His 65th Birthday, George T. F. Wong, Robert F. Anderson, Michael P. Bacon, Hein J. W. De Baar, James W. Murray, Mary I. Scranton

OES Faculty Publications

Peter George Brewer is an ocean chemist of the rare breed that can cross back and forth over the divide between being a front-line research scientist and being a research executive. As if that is not remarkable enough, in the process, he has also demonstrated sustained growth in the depth, breadth, and diversity of his scientific endeavors. Some of his formidable contributions to ocean chemistry have already been highlighted in a profile of him as a major mover and shaker in the field (Irion, 2001). Here, we provide additional glimpses of him from the perspective of a group of individuals …

Sublethal And Killing Effects Of Atmospheric-Pressure, Nonthermal Plasma On Eukaryotic Microalgae In Aqueous Media, Ying Zhong Tang, Xin Pei Lu, Mounir Laroussi, Fred C. Dobbs

OES Faculty Publications

In-depth studies on the interaction of nonthermal plasmas with microorganisms usually focus on bacteria; only little attention has been given to their effects on more complex eukaryotic cells. We report here nonthermal plasma's effects on cell motility, viability staining, and morphology of eukaryotic microalgae, with three marine dinoflagellates and a marine diatom as major targets. The effects on motility and viability staining depended on the time of exposure to plasma and the species of microalgae. We observed a strong pH decrease in aqueous samples (marine and freshwater algal cultures, their culture media, and deionized water) after exposure to plasma, and …

Forcing And Dynamics Of Seafloor-Water Column Exchange On A Broad Continental Shelf, William B. Savidge, Ann Gargett, Richard A. Jahnke, James R. Nelson, Dana K. Savidge, R. Timothy Short, George Voulgaris

OES Faculty Publications

Relict sediments of elevated permeability characterize the majority of continental shelves globally (Emery, 1968). In these settings, interactions between benthic boundary layer (BBL) flows and seabed topography generate pressure fluctuations that drive advective and dispersive porewater transport, dramatically increasing the magnitude and variability of porewater solute and particulate exchange across the sediment-water interface (Huettel et al., 1996; Huettel and Rusch, 2000). On broad shallow shelves with a relatively large area-to-volume ratio, the seafloor’s role is magnified. Energetic events may reorganize bedforms across a significant fraction of the shelf, leading to altered exchange dynamics that may persist long after the organizing …

Impacts Of Chromophoric Dissolved Organic Material On Surface Ocean Heating In The Chukchi Sea, Victoria J. Hill

OES Faculty Publications

Recent observations show visible light attenuation in the Arctic Ocean to be greater than previously assumed. High attenuation observed during the period prior to ice melt and increased phytoplankton production, was attributed primarily to the high levels of absorption by chromophoric dissolved organic material ( CDOM) present in these waters. Preliminary evidence suggests this material is produced by ice algae in the early spring. Optical data from the Chukchi shelf system collected in the spring and summer of 2002, were used to model energy absorption in the mixed layer by both dissolved and particulate material. In the spring, absorption by …

Food Limitation In Larval Fish: Ontogenetic Variation In Feeding Scope And Its Potential Effect On Survival, Alexander B. Bochdansky, Peter Grønkjær, Pierre Pepin, William C. Leggett

OES Faculty Publications

We used the radiated shanny Ulvaria subbifurcataas a model species to explore the relative gut fullness from hatch to metamorphosis of wild larvae, and compared these values with those of laboratory-reared larvae fed at maximum rates. Ingestion rates of most wild larvae were above starvation levels but below the maximum feeding levels of laboratory-reared larvae. Twenty-six percent of freshly-hatched wild larvae and 11% of large, pre-settlement wild larvae had insufficient food in their stomach to satisfy metabolic requirements. These results, taken on their own, are consistent with the much hypothesized increased foraging performance and survival of larger larvae relative …

Turbulent Lifestyle: Microbial Mats On Earth’S Sandy Beaches—Today And 3 Billion Years Ago, Nora Noffke

OES Faculty Publications

Archean Earth history is very difficult to reconstruct. Until recently, only bacterial cells preserved in chert, microborings, and stromatolites provided the few clues to ancient life. Now, siliciclastic “microbially induced sedimentary structures” (MISS) are adding to our knowledge of both past life and paleoenvironments. MISS rise from the interaction of photoautotrophic microbial mats with physical sediment dynamics in siliciclastic, shallow-marine settings. Archean MISS can be understood through observations of living microbial mats and modern biotic-physical sedimentary processes. Such geobiological studies are key to the interpretation of the early evolution of prokaryotes. For example, the 2.9 Ga Pongola Supergroup, South Africa, …

In Re D.F.: The South Dakota Supreme Court Misses An Opportunity To Establish An Appropriate Due Diligence Standard When Serving Notice By Publication In Parental Rights Termination Proceedings, Derek Andrew Nelsen

South Dakota Law Review

No abstract provided.

Ship Ballast Tanks: How Microbes Travel The World, Fred C. Dobbs

OES Faculty Publications

As the international shipping fleet travels the oceans, it carries with it hidden cargoes of microbes. Fred C. Dobbs explores the hazards posed and what can be done to counteract them.

Legal Status And Effect On Children, Margaret F. Brinig, Steven L. Nock

Journal Articles

One of the haunting claims of each poor, unmarried mother in Edin and Kefalas' Promises I Can Keep is that at least she can guarantee she will love her child, even though she cannot promise to make a lifelong commitment to a mate. That love, each young mother says, will be a sustaining gift both to her and the child. Similarly, in work done by sociologists McLanahan and Garfinkel to counteract the claim that it was not single parenting that made children's prospects dim, but poverty, sociologists have found that many of the bad effects of single parenting go away …

The Grim Word: 'Home' In Fiction By Graham Greene, Geoff Cowgill

Masters Theses

Graham Greene's treatment of the subject of home in his writings is remarkably negative. Focusing on nine of his major novels (England Made Me, A Gun for Sale, Brighton Rock, The Heart of the Matter, The Quiet American, The Comedians, Travels with My Aunt, The Honorary Consul, and The Human Factor), this study explicates the ways in which home fails his characters. In this thesis, 'home' has been split into three facets: family, domicile and homeland. Each facet seems to promise benefits for the characters that don't materialize. The way in which Greene's writing promotes a betrayal of home reflects …

Effect Of Living Arrangement And Meals Eaten Alone On The Nutrition Status Of Older Adults, Kelly L. Boeger

Masters Theses

The purpose of the study was to determine if older adults who live alone are at greater nutritional risk than those who do not live alone and to determine if eating with -'others increases nutritional status in older adults. A questionnaire, adapted from the "Determine Your Nutritional Health Checklist" developed by the Nutrition Screening Initiative, was administered to 100 older adults 65 years of age or older. Ninety-four survey participants were included in the study.

Nutrition scores from the nutrition assessment portion were compiled for each subject by categorizing each questionnaire as low, moderate, or high~ depending on level of …

Bullying And Victimization In High School As Perceived By Female Students In A Midwestern University, Shannon Y. Schwab

Masters Theses

Bullying and victimization increased tremendously over the past 2 decades and are presently one of the most enduring and underrated problems in U.S. schools. Much of the research available on bullying has focused primarily on males; however, recently, research has shown that females are just as likely as males to engage in bullying behaviors. Unfortunately, female bullying occurs quite frequently, yet remains unrecognized because it is often overlooked. Females tend to prefer more indirect forms of bullying behaviors in order to keep it anonymous. The focus of the current research was to examine the nature and frequency of female bullying …

Soil Sisters: Independent Land Owning Women In Coles And Douglas Counties, Illinois, 1870-1930, Rachel E. Kleinschmidt

Masters Theses

In the Midwest during the late nineteenth and early twentieth centuries, many women owned and worked on farmland, but the male-dominated capitalistic farming system negated much of the legal and economic authority they had as farmers. Progressive Era changes in the farming system shifted family farming systems to profit-driven business-oriented farms, marginalizing women's productive contributions. Single and widowed women farmers in Coles and Douglas Counties in Illinois managed to retain ownership of farm land despite gender and legal biases inherent in common law practices defined by patriarchy.

A survey of local history sources, including federal census data, probate records, and …

The Making Of A Middlerace: The Social Politics Surrounding Black-White Interracial Marriages And Black White Biracial Identity, Yoftahe K. Manna

Masters Theses

In an attempt to uncover the social politics surrounding Black-White interracial marriages and Black-White biracial identity, this thesis investigates outsiders' and insiders' perspectives on the issues. Black and White participants of the study reported positive attitudes toward Black-White interracial marriage, while they reported negative attitudes toward Black-White biracial individuals. No statistically significant differences were found between Blacks and Whites in attitudes toward Black-White interracial marriages and Black-White biracial identity. No statistically significant differences were found between men and women, either. The insiders' reports, however, contradicted these findings. Both Black-White interracial couple and Black-White biracial adult participants of this study reported …

An Exploration Of The Perception Of Collective Identity Threat Among Muslim Students In Higher Education, Donna Vitale

Masters Theses

The purpose of the present study was to examine the perspectives of Muslim students in higher education concerning their connections to campus based on their perceptions of collective identity threat. Collective identity exists when an individual holding group membership fears that in-group members' behavior will reinforce a negative stereotype about their group. Similarly, stereotype threats are personally relevant threats in which individuals may fear reinforcing the stereotype themselves (Cohen & Garcia, 2005). Research in the area of stereotype threat has high generalizability and can transfer to any race or gender (Steele, Spencer, & Aronson, 2002). For the purpose of the …

Female And Male Student Leadership Characteristics: Differences & Similarities, Amber Mishala Shaverdi

Masters Theses

Females and males differ in a variety of areas, yet these genders also have similar qualities. Are these similarities and differences affecting our college environment? In this research thesis the researcher set out to gather data that identifies the similarities and differences among undergraduate student leaders at a mid-sized Midwest public institution. The researcher first identifies student involvement and the many advantages for students who choose to be involved in cocurricular activities. Literature is presented highlighting a variety of theories that identify gender differences among females and males. The theories range from male masculinity, cognitive development, and societal gender roles. …

A Genetic Assessment Of The Red Squirrel In Illinois: Natives, Immigrants, Or Exotics?, William Beatty

Masters Theses

A small population ofred squirrels (Tamiasciurus hudsonicus) has existed in Iroquois County, Illinois since the 1970' s. The origin of this population is unknown, but some accounts suggest they are the offspring of released red squirrels from Minnesota. Alternatively, they may be a remnant Illinois population or more recent immigrants from Indiana. Finally, this population could reflect a mixed ancestry of the above scenarios. Mitochondrial DNA (mtDNA) was utilized to determine the genetic relationships among red squirrel populations in Illinois, Indiana, Michigan, Minnesota, and Wisconsin. My results showed low levels of haplotype diversity and nucleotide diversity in the Illinois sample. …

Beneficial Effects Of Estradiol Are Mediated Through Apoe, Aseem Hussain

Masters Theses

Estradiol is the primary premenopausal hormone circulating in women. It is a powerful hormone in the female body since it sends signals to the brain, regulates ovulation and menstrual cycle and acts on the nervous syste~ heart, breast and many other tissues in the body. However all estradiol production is stopped after menopause. Post menopausal women can develop a host of neurodegenerative diseases such as Alzheimer's disease. If the onset of progressive dementia is after menopause during loss of estradiol, it seems logical to assume that the lack of estradiol should have a big role to play in the pathogenesis …

Tracing Sperm In Multiply-Mated Female Anastrepha Suspensa, (Diptera:Tephridae), Preeti Dhakal

Masters Theses

Anastrepha suspensa females have four different sites of sperm storage in their reproductive tract, may mate with more than one male, and store sperm in differing amounts in each organ after copulation. In order to study the dynamics of sperm storage patterns and subsequent paternity outcomes, a method was developed for both genotyping and quantifying sperm in the spermathecae. Spermathecae were isolated and sonicated to remove maternal cells, and subsequently crushed between two microslides to release sperm from the capsule. After DNA isolation, microsatellite loci could be amplified by PCR for fragment analysis. A newly developed method was then used …

Artificial Riffles As A Stream Remediation Technique, Bethany S. Harrington

Masters Theses

No abstract provided.

Influence Of Seed Source On Vegetative And Reproductive Performance Of Three Common Prairie Grasses Common In Grassland Restoration, Matt Burmeister

Masters Theses

Though tallgrass prairie once covered 250 million acres of the midwestem U.S, now less than one percent· of this original area is left. In recent years the restoration and reconstruction of tallgrass prairie has become more popular throughout the prairie region. There is evidence that local and distant populations may both be practical seed sources for ecological restoration projects. To address this basic issue in restoration, I tested the how performance of three grass species from different locations was affected by the distance from the restored area. Three species, Andropogon gerardii, Sorghastrum nutans and Panicum virgatum, of perennial grasses common …

Family Structure And Psychological Factors: The Effects Of Family-Of-Origin Variables On Young Adults' Psychological Well-Being, Catherine E. Morgan

Masters Theses

This study aimed to investigate the relationship between family structure and life satisfaction in young adults. Additionally, the study examined explanatory style, parenting style, family cohesion, family satisfaction, and the presence of siblings as potential moderating factors between divergent family structures and levels of life satisfaction in young adults. Ninety male and 121 female university students completed a demographic survey, the Parental Authority Questionnaire, the Family Adaptability and Cohesion Evaluation Scales IV, the Attribution Style Questionnaire, the Family Satisfaction Scale, and the Satisfaction with Life Scale. As anticipated, results indicated that participants who grew up in single parent and step-family …

Comparative Study Between Wild Rice (Oryza Rufipogon) And Domesticated Rice (Oryza Sativa Ssp Japonica) Chromosome 8 Centromere, Soham Aso

Theses, Dissertations and Culminating Projects

Rice has one of the simplest of the monocotyledonous genomes analyzed to date. The Oryza sativa genome is made of 12 chromosomes and has a total length of 430 MB. It is highly syntenic amongst other cereals. Therefore, genetic distances of these organisms are surprisingly very similar, meaning that genomic recombinations in each cereal occur at much the same frequency despite the differences in their genome size. The reason for this synchrony in recombinations may be due to similar lengths of gene-rich and gene-rare regions. This study focuses on the gene-rare repetitive centromeric region of rice chromosome 8. Although the …

Proxy-Based Reconstructions Of Hemispheric And Global Surface Temperature Variations Over The Past Two Millennia, Michael E. Mann, Scott Rutherford

Arts & Sciences Faculty Publications

Following the suggestions of a recent National Research Council report [NRC (National Research Council) (2006) Surface Temperature Reconstructions for the Last 2,000 Years (Natl Acad Press, Washington, DC).], we reconstruct surface temperature at hemispheric and global scale for much of the last 2,000 years using a greatly expanded set of proxy data for decadal-to-centennial climate changes, recently updated instrumental data, and complementary methods that have been thoroughly tested and validated with model simulation experiments. Our results extend previous conclusions that recent Northern Hemisphere surface temperature increases are likely anomalous in a long-term context. Recent warmth appears anomalous for at least …

Naturally Present Fatty Acids As Internal Calibrants For Fourier Transform Mass Spectra Of Dissolved Organic Matter, Rachel L. Sleighter, Georgina A. Mckee, Zhanfei Liu, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The analysis of dissolved organic matter ( DOM) by Fourier transform ion cyclotron resonance mass spectrometry ( FTICR- MS) has gained wide interest recently, driven primarily by its ultrahigh resolving power and mass accuracy. Accurate calibration of mass spectra is a key step to successfully decipher the DOM components. We propose a simple and accurate method to internally calibrate the peaks in the complex spectra without the need to add a calibrant. Mass spectra of DOM samples from the Dismal Swamp, Virginia, and the lower Chesapeake Bay display the presence of naturally occurring fatty acids which can be readily recognized …