Life Sciences Commons^™

Feature Selection And Classification Of Maqc-Ii Breast Cancer And Multiple Myeloma Microarray Gene Expression Data, Qingzhong Liu, Andrew H. Sung, Zhongxue Chen, Jianzhong Liu, Xudong Huang, Youping Deng

Faculty Publications

Microarray data has a high dimension of variables but available datasets usually have only a small number of samples, thereby making the study of such datasets interesting and challenging. In the task of analyzing microarray data for the purpose of, e.g., predicting gene-disease association, feature selection is very important because it provides a way to handle the high dimensionality by exploiting information redundancy induced by associations among genetic markers. Judicious feature selection in microarray data analysis can result in significant reduction of cost while maintaining or improving the classification or prediction accuracy of learning machines that are employed to sort …

Conservation Genetics And Systematics Of Several Turtles Species In The Southeastern United States, Joshua Robert Ennen

Dissertations

Chelonians (i.e., turtles) are an imperiled group of reptiles with about 66% of the recognized species listed as threatened by the IUCN. Most chelonian species have a unique set of life history traits (i.e., longevity, delayed sexual maturity, and low juvenile survivorship), which makes their populations exceedingly sensitive to increases in adult and juvenile moralities. With numerous anthropogenic effects (e.g., habitat alteration, exploitation, and over harvesting) negatively influencing mortality rates, chelonians have experienced global precipitous declines and extinctions.

This dissertation focuses on species within two chelonian genera, Gopherus and Graptemys. Although these two genera are vastly different ecologically, they are …

Remote Sensing Of Harmful Algal Blooms In The Mississippi Sound And Mobile Bay: Modelling And Algorithm Formation, Dan Martin Holiday

Dissertations

The incidence and severity of harmful algal blooms have increased in recent decades, as have the economic effects of their occurrence./The diatom Pseudo-nitzschia spp. caused fisheries closures in Mobile Bay during 2005 due to elevated levels of domoic acid. In the previous 4 years Karenia brevis counts of >5,000 cells L"1 have occurred in Mobile Bay and the Mississippi Sound. Population levels of this magnitude had previously been recorded only in 1996. Increases in human populations, urban sprawl, development of shoreline properties, sewage effluent and resultant changes in NP ratios of discharge waters, and decline in forest and marsh lands, …

Experimental Population Dynamics Of Amyloodiniumocellatum In The Spotted Seatrout, Cynoscion Nebulosus, And The Red Snapper, Lutjanus Campechanus, Ignacio Masson

Dissertations

Amyloodinium ocellatum is a parasitic dinoflagellate that infects warm water marine bony fishes and causes high mortalities in aquaculture settings. It has three life history stages: the feeding trophont, the reproductive tomont, and the infective dinospore. This dissertation describes the characteristics of A. ocellatum infections in juvenile spotted seatrout, Cynoscion nebulosus, and red snapper, Lutjanus campechanus, studies the survival and fecundities of the stages in the life cycle of the parasite and presents a population model for A. ocellatum.

At 25°C and 33 ppt, the peak of trophont detachment occurred on day 2 postinfection in spotted seatrout and day 3 …

Heterologous Expression Studies Of Saccharomyces Cerevisiae Reveal Two Distinct Trypanosomatid Caax Protease Activities And Identify Their Potential Targets, David Z. Mokry, Surya P. Manandhar, Kristen A. Chicola, George M. Santangelo, Walter K. Schmidt

Faculty Publications

The CaaX tetrapeptide motif typically directs three sequential posttranslational modifications, namely, isoprenylation, proteolysis, and carboxyl methylation. In all eukaryotic systems evaluated to date, two CaaX proteases (Rce1 and Ste24/Afc1) have been identified. Although the Trypanosoma brucei genome also encodes two putative CaaX proteases, the lack of detectable T. brucei Ste24 activity in trypanosome cell extracts has suggested that CaaX proteolytic activity within this organism is solely attributed to T. brucei Rce1 (J. R. Gillespie et al., Mol. Biochem. Parasitol. 153: 115-124. 2007). In this study, we demonstrate that both T. brucei Rce1 and T. brucei Ste24 are enzymatically active when …

Water Uptake Threshold Of Rabbiteye (Vaccinium Ashei) Blueberries And Its Influence On Fruit Splitting, Donna A. Marshall-Shaw, James M. Spiers, Kenneth J. Curry

Faculty Publications

Split-resistant and split-susceptible rabbiteye blueberry fruit were evaluated at all stages of development to determine ''water uptake thresholds'' by soaking in distilled water. Weight increase after soaking was measured, and percent weight gain was calculated to take into consideration the weight increase of the fruit from development. The ratio of percent increase in volume to weight increase resulting from water uptake was calculated. Ratios of percent water uptake to weight increase between splitsusceptible 'Tifblue' and split-resistant 'Premier' blueberries were found to be similar. The split-susceptible 'Tifblue' had a 1.6 g/50 fruit increase with a 1.7% water uptake and a ratio …

Sensitivity Of The Carbon Cycle In The Arctic To Climate Change, A. David Mcguire, Leif G. Anderson, Torben R. Christensen, Scott Dallimore, Laodong Guo, Daniel J. Hayes, Martin Heimann, Robie W. Macdonald, Nigel Roulet

Faculty Publications

The recent warming in the Arctic is affecting a broad spectrum of physical, ecological, and human/cultural systems that may be irreversible on century time scales and have the potential to cause rapid changes in the earth system. The response of the carbon cycle of the Arctic to changes in climate is a major issue of global concern, yet there has not been a comprehensive review of the status of the contemporary carbon cycle of the Arctic and its response to climate change. This review is designed to clarify key uncertainties and vulnerabilities in the response of the carbon cycle of …

The Pentameric Vertex Proteins Are Necessary For The Icosahedral Carboxysome Shell To Function As A Co2 Leakage Barrier, Fei Cai, Balaraj B. Menon, Gordon C. Cannon, Kenneth J. Curry, Jessup M. Shively, Sabine Heinhorst

Faculty Publications

Background

Carboxysomes are polyhedral protein microcompartments found in many autotrophic bacteria; they encapsulate the CO₂ fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) within a thin protein shell and provide an environment that enhances the catalytic capabilities of the enzyme. Two types of shell protein constituents are common to carboxysomes and related microcompartments of heterotrophic bacteria, and the genes for these proteins are found in a large variety of bacteria.

Methodology/Principal Findings

We have created a Halothiobacillus neapolitanus knockout mutant that does not produce the two paralogous CsoS4 proteins thought to occupy the vertices of the icosahedral carboxysomes and related microcompartments. Biochemical …

Nutrition Literacy Status And Preferred Nutrition Communication Channels Among Adults In The Lower Mississippi Delta, Jamie Zoellner, Carol L. Connell, Wendy Bounds, Lashaundrea Crook, M. Kathleen Yadrick

Faculty Publications

Introduction

The objective of this cross-sectional study was to examine the nutrition literacy status of adults in the Lower Mississippi Delta.

Methods

Survey instruments included the Newest Vital Sign and an adapted version of the Health Information National Trends Survey. A proportional quota sampling plan was used to represent educational achievement of residents in the Delta region. Participants included 177 adults, primarily African Americans (81%). Descriptive statistics, X(2) analysis, analysis of variance, and multivariate analysis of covariance tests were used to examine survey data.

Results

Results indicated that 24% of participants had a high likelihood of limited nutrition literacy, 28% …

A Method Of Successive Corrections Of The Control Subspace In The Reduced-Order Variational Data Assimilation, Max Yaremchuk, Dmitri A. Nechaev, Gleb Panteleev

Faculty Publications

A version of the reduced control space four-dimensional variational method (R4DVAR) of data assimilation into numerical models is proposed. In contrast to the conventional 4DVAR schemes, the method does not require development of the tangent linear and adjoint codes for implementation. The proposed R4DVAR technique is based on minimization of the cost function in a sequence of low-dimensional subspaces of the control space. Performance of the method is demonstrated in a series of twin-data assimilation experiments into a nonlinear quasigeostrophic model utilized as a strong constraint. When the adjoint code is stable, R4DVAR's convergence rate is comparable to that of …

The Use And Perceptions Of Concept Mapping As A Learning Tool By Dietetic Internship Students And Preceptors, Elaine Fontenot Molaison, Kimberly Taylor, Dawn Erickson, Carol Connell

Faculty Publications

Critical thinking and problem solving skills are currently emphasis areas in the education of allied health professionals. Use of concept maps to teach these skills have been utilized primarily in nursing and medical education, but little has been published about their use in dietetics education. Therefore the purpose of this study was to evaluate the potential efficacy of concept mapping as a learning tool for nutrition assessment among dietetic interns and its acceptability by internship preceptors. Nineteen dietetic interns and 31 preceptors participated in a quasi-experimental pre-/post-design in which the concept mapping strategy was taught as a replacement for the …

Transcriptome Analysis Of Frog Virus 3, The Type Species Of The Genus Ranavirus, Family Iridoviridae, Sai Majji, V. Thodima, R. Sample, D. Whitley, Y. Deng, J. Mao, V. Gregory Chinchar

Faculty Publications

Frog virus 3 is the best characterized species within the genus Ranavirus, family Iridoviridae. FV3's large (similar to 105 kbp) dsDNA genome encodes 98 putative open reading frames (ORFs) that are expressed in a coordinated fashion leading to the sequential appearance of immediate early (IE), delayed early (DE) and late (L) viral transcripts. As a step toward elucidating molecular events in FV3 replication, we sought to identify the temporal Class Of Viral messages. To accomplish this objective an oligonucleotide microarray containing 70-mer probes corresponding to each of the 98 FV3 ORFs was designed and used to examine viral gene expression. …

Mouse Embryonic Stem Cells Lacking P38Α And P38Δ Can Differentiate To Endothelial Cells, Smooth Muscle Cells, And Epithelial Cells, Samujjwal Chakraborty, Baobin Kang, Faqing Huang, Yan-Lin Guo

Faculty Publications

The p38 mitogen-activated protein (MAP) kinases (p38) are important signaling molecules that regulate various cellular processes. Four isoforms of p38 family, p38α, p38β, p38γ, and p38δ, have been identified in mammalian cells. Previous studies have shown that p38α knockout is embryonic lethal in mice. At the cellular level, p38α is abundantly expressed in mouse embryonic stem cells (ESCs), but p38α knockout (p38α-/-) ESCs can differentiate to endothelial cells (ECs), smooth muscle cells (SMCs), and neurons. We speculate that the lost function of p38α in p38α-/- ESCs may be compensated for by the redundant function of other isoforms. To test this …

Evaluation Of Cay-1, An Experimental, Natural Fungicide, For Control Of Strawberry Pathogens, Kenneth J. Curry, Maritza Abril, Anthony J. Delucca, Stephen M. Boue, Barbara J. Smith, David E. Wedge

Faculty Publications

CAY-1 is an experimental, natural product being tested as a potential fungicide. This saponin isolated from Capsicum frutescens interacts with membrane sterols causing leakage of cell components and ultimately cell death in a variety of fungi. CAY-1 and the commercial fungicide captan were tested in an in vitro doseresponse dilution-broth assay. They caused at least 85% growth inhibition of the fungal pathogens Colletotrichum acutatum, C fragariae and C. gloeosporioides when tested at 3.0 μM. Even though CAY-1 strongly reduced the growth of these fungal pathogens in laboratory assays and prevented anthracnose development in detached leaf assays, it did not …

Remote Sensing And Mapping Of Tamarisk Along The Colorado River, Usa: A Comparative Use Of Summer-Acquired Hyperion, Thematic Mapper And Quickbird Data, Gregory A. Carter, Kelly L. Lucas, Gabriel A. Blossom, Cheryl L. Lassitter, Dan M. Holiday, David S. Mooneyhan, Danielle R. Fastring, Tracy R. Holcombe, Jerry A. Griffith

Faculty Publications

Tamarisk (Tamarix spp., saltcedar) is a well-known invasive phreatophyte introduced from Asia to North America in the 1800s. This report compares the efficacy of Landsat 5 Thematic Mapper (TM5), QuickBird (QB) and EO-1 Hyperion data in discriminating tamarisk populations near De Beque, Colorado, USA. As a result of highly correlated reflectance among the spectral bands provided by each sensor, relatively standard image analysis methods were employed. Multispectral data at high spatial resolution (QB, 2.5 m Ground Spatial Distance or GSD) proved more effective in tamarisk delineation than either multispectral (TM5) or hyperspectral (Hyperion) data at moderate spatial resolution (30 m …

Detecting Proteins In Highly Autofluorescent Cells Using Quantum Dot Antibody Conjugates, Karen M. Orcutt, Shanshan Ren, Kjell Gundersen

Faculty Publications

We have applied quantum dot (Qdot) antibody conjugates as a biomolecular probe for cellular proteins important in biogeochemical cycling in the sea. Conventional immunological methods have been hampered by the strong autofluorescence found in cyanobacteria cells. Qdot conjugates provide an ideal alternative for studies that require long-term imaging of cells such as detection of low abundance cellular antigens by fluorescence microscopy. The advantage of Qdot labeled probes over conventional immunological methods is the photostability of the probe. Phycoerythrin bleaches in cyanobacterial cells under prolonged UV or blue light excitation, which means that the semiconducting nanocrystal probe, the Qdot, can yield …

The Tbx20 Homologs Midline And H15 Specify Ventral Fate In The Drosophila Melanogaster Leg, Pia C. Svendson, Ann Formaz-Preston, Sandra M. Leal, William J. Brook

Faculty Publications

Regional fates in the developing limbs of Drosophila melanogaster are controlled by selector gene transcription factors. Ventral fate in the fly leg is specified by the expression of the ligand Wingless. We present evidence that midline and H15, members of the Tbx20 class of T-box transcription factors, are key mediators of the Wingless signal in the formation of the ventral region of the fly leg. midline and H15 are restricted to identical ventral domains of expression through activation by Wingless and repression by the dorsal signal Decapentaplegic. midline and H15 function redundantly and cell autonomously in the formation of …

Sport As A Vehicle For Socialization And Maintenance Of Cultural Identity: International Students Attending American Universities, James Taylor Allen

Dissertations

Sport can be utilized by immigrants as a vehicle for maintaining cultural identity. Conversely, sport participation provides immigrants with opportunities for adopting an entirely new culture. Previous research also suggests that sport provides individuals with opportunities for attaining social capital. While this can be a beneficial situation for some, sport is also promoting elitism and serving as a powerful mechanism for exclusion. Globalization has led large numbers of foreign nationals to seek educational opportunities in the United States. Due to the increase in the number of international students and the lack of empirical studies, the need to study their participation …

Bridging Functional Genomics And Toxicogenomics Through Dna Microarrays In A Fish Model, Shuzhao Li

Dissertations

In a case study of finding gene expression signatures for environmental stressors in Cyprinodon variegatus, this dissertation examines several important issues of applying DNA microarray technology to fish toxicogenomics. The most relevant disciplines, fish toxicogenomics and computational systems biology are reviewed in Chapter 1. Chapter 2 reviews major aspects of DNA microarray technology.

On DNA microarrays, even for probes that target the same transcript, large variations are seen in the probe signals. These variations are partly dependent and partly independent on probe sequences. Chapter 3 estimates the sequence independent variation by combining experimental and computational approaches. Chapter 4 and …

Reverse Engineering Of Gene Regulatory Networks For Discovery Of Novel Interactions In Pathways Using Gene Expression Data, Tanwir Habib

Dissertations

A variety of chemicals in the environment have the potential to adversely affect the biological systems. We examined the responses of Rat (Rattus norvegicus) to the RDX exposure and female fathead minnows (FHM, Pimephales promelas) to a model aromatase inhibitor, fadrozole, using a transcriptional network inference approach. Rats were exposed to RDX and fish were exposed to 0 or 30mg/L fadrozole for 8 days. We analyzed gene expression changes using 8000 probes microarrays for rat experiment and 15,000 probe microarrays for fish. We used these changes to infer a transcriptional network. The central nervous system is remarkably plastic in its …

The Relationship Between Calcium Intake, Obesity, And Cardiovascular Disease Risk Factors: The Jackson Heart Study, Marjuyua Lartey-Rowser

Dissertations

Cardiovascular disease (CVD) is a major health risk in the United States. Major indicators of CVD risk include obesity, blood lipids, and blood pressure. Modifiable risk factors associated with CVD include body composition (body mass index and waist circumference), serum lipids, and blood pressure. Data suggest calcium intake may play a role in regulation of weight, serum lipids, and blood pressure. The purpose of this study was to assess relationships of dietary calcium intake with weight status, and cardiovascular disease risks in African American population participating in the Jackson Heart Study.

The subjects included 4,267 African American adults ages 21-95 …

Inferring Gene Regulatory Networks From Time Series Microarray Data, Peng Li

Dissertations

The innovations and improvements in high-throughput genomic technologies, such as DNA microarray, make it possible for biologists to simultaneously measure dependencies and regulations among genes on a genome-wide scale and provide us genetic information. An important objective of the functional genomics is to understand the controlling mechanism of the expression of these genes and encode the knowledge into gene regulatory network (GRN). To achieve this, computational and statistical algorithms are especially needed.

Inference of GRN is a very challenging task for computational biologists because the degree of freedom of the parameters is redundant. Various computational approaches have been proposed for …

Factors Influencing The Environmental Quality Of The Bay Of Saint Louis, Mississippi And Implications For Evolving Coastal Management Policies, Pradnya Ankush Sawant

Dissertations

The Bay of St. Louis, MS is a small northern Gulf of Mexico estuary that has been identified by the Mississippi Department of Environmental Quality (MDEQ) as an impaired waterbody for its designated uses, mainly due to the presence of pollutant pathogens. A systematic study of this estuary was important to understand the behavior and responses of the bay to several natural and anthropogenic forcing factors. A 14- month long study (bimonthly sampling) to evaluate its environmental quality was undertaken from April 2003 to May 2004. Environmental quality was defined as "the health of an ecosystem characterized in terms of …

Morphological Deformities As Biomarkers In Fish From Contaminated Rivers In Taiwan, Peter Lin Sun, William E. Hawkins, Robin M. Overstreet, Nancy J. Brown-Peterson

Faculty Publications

Tilapia (Oreochromis spp.) were collected seasonally from four contaminated rivers in southwestern Taiwan for studies of morphological deformities that could be used as biomarkers of contamination. Morphological deformities found in tilapia were separated into 15 categories. Overall, the prevalence of deformities such as split fins, lower lip extension and gill deformities were significantly related to various water quality parameters, including low DO and high ammonium, lead and zinc concentrations. The persistence of tilapia in polluted waters and the development of a suite of morphological deformities suggest that tilapia can be used as sentinels of non-point source pollution in rivers.

Chemical And Isotopic Characterization Of Size-Fractionated Organic Matter From Cryoturbated Tundra Soils, Northern Alaska, Chunhao Xu, Laodong Guo, Chien-Lu Ping, Daniel M. White, Thomas D. Lorenson

Faculty Publications

Recent studies indicate a second layer of organic matter often accumulates in the lower active layer and upper permafrost in arctic tundra soils as a result of cryoturbation. In this study, cryoturbated organic matter was characterized using a combination of physical size fractionation and modern analytical techniques for elemental composition (C and N), stable isotopes (delta(13) C and delta(15)N), radiocarbon content (Delta(14)C), and molecular fingerprinting (pyrolysis-gas chromatography/mass spectrometry, Py-GC/MS). The results indicated that cryoturbated organic matter could be highly bioavailable. Soil organic matter (SOM) associated with fine sand particles was considered to be the organic carbon pool most sensitive to …

On The Mechanisms Of Episodic Salinity Outflow Events In The Strait Of Hormuz, Prasad G. Thoppil, Patrick J. Hogan

Faculty Publications

Observations in the Strait of Hormuz (26.26 degrees N, 56.08 degrees E) during 1997-98 showed substantial velocity fluctuations, accompanied by episodic changes in the salinity outflow events with amplitude varying between 1 and 2 psu on time scales of several days to a few weeks. These events are characterized by a rapid increase in salinity followed by an abrupt decline. The mechanisms behind these strong pulses of salinity events are investigated with a whigh-resolution (similar to 1 km) Hybrid Coordinate Ocean Model (HYCOM) with particular reference to the year 2005. In accordance with the observations, the simulated salinity events are …

The Effects Of Climate Variability On The Structure Of The Phytoplankton Community In Tumaco Bay, Colombia, Ingrid Garcia-Hansen Honkala

Dissertations

Spatiotemporal variability in the diatom and dinoflagellate community structure and chlorophyll a (chl a) concentrations in Tumaco Bay during the 1993-2005 period was related clearly to seasonal and interannual variability in environmental conditions due to the migration of the Inter-tropical Convergence Zone (ITZC) and the influence of El Nino Southern Oscillation (ENSO) events. A total of 134 species of diatoms that belong to 57 genera, and 78 species of dinoflagellates that belong to 25 genera were identified during the survey. The diatom community was the dominant group in the waters of the bay, being the most abundant with the greatest …

Oceanic-Atmospheric Modes Of Variability And Their Effect On River Flow And Blue Crab (Callinectes Sapidus) Abundance In The Northcentral Gulf Of Mexico, Guillermo Humberto Sanchez-Rubio

Dissertations

Oceanic-atmospheric modes of variability occur on interdecadal, multidecadal, decadal, and interannual timescales and their influence on climate around the world has been confirmed. The present study investigates Mississippi River and Pascagoula River flows in response to the influence of one or more of the four oceanic-atmospheric modes of variability: the Pacific Decadal Oscillation (PDO), the Atlantic Multidecadal Oscillation (AMO), the North Atlantic Oscillation (NAO), and the El Nino Southern Oscillation (ENSO). These modes of variability are present in phases: PDO warm (PDOw) and cold (PDOc), AMO warm (AMOw) and cold (AMOc), NAO positive (NAOp) and negative (NAOn), and ENSO warm …

The Effects Of Dolphin Education Programs On Visitors' Conservation-Related Knowledge, Attitude And Behavior, Lance Joseph Miller

Dissertations

Zoological institutions typically exhibit dolphins in educational programs such as dolphin shows and interaction programs. The goal of these programs is to entertain visitors while increasing their conservation-related knowledge, attitude and behavior towards dolphins and the marine environment. The purpose of the current study was to examine dolphin shows and interaction programs in terms of their effectiveness in meeting these goals. A multi-institutional study was conducted at six different facilities throughout the United States. A repeated measures design was used to examine the knowledge, attitude and behavior of visitors before, immediately after and three months following participation in dolphin shows …

My Two Boots ... A Walk Through The Wetlands. An Annual Outing For 700 Middle School Students, Julie Cwikla, Mark Lasalle, Sybil Wilner

Faculty Publications

No abstract provided.