Life Sciences Commons^™

Jellyfish, Forage Fish, And The World's Major Fisheries, Kelly L. Robinson, James J. Ruzicka, Mary Beth Decker, Richard D. Brodeur, Frank J. Hernandez, Javier Quiñones, E. Marcelo Acha, Shin-Ichi Uye, Hermes Mianzan, William M. Graham

Faculty Publications

A majority of the world’s largest net-based fisheries target planktivorous forage fish that serve as a critical trophic link between the plankton and upper-level consumers such as large predatory fishes, seabirds, and marine mammals. Because the plankton production that drives forage fish also drives jellyfish production, these taxa often overlap in space, time, and diet in coastal ecosystems. This overlap likely leads to predatory and competitive interactions, as jellyfish are effective predators of fish early life stages and zooplankton. The trophic interplay between these groups is made more complex by the harvest of forage fish, which presumably releases jellyfish from …

Dialect Use Within A Socially Fluid Group Of Southern Resident Killer Whales, Orcinus Orca, Courtney Elizabeth Smith

Master's Theses

Resident killer whales, Orcinus orca, of the Northeastern Pacific form stable kinship-based matrifocal associations and communicate with group-specific repertoires of discrete calls (dialects) that reflect these associations. The gradual fission of matrilines is usually consistent with dialect variations among groups that may manifest as differences in call usage at the repertoire level or subtle structural differences of the calls themselves. Therefore, matrilines that are more closely related tend to be more acoustically similar. Within the endangered community of Southern Resident killer whales (SRKWs), recent evidence shows that one particular group (L pod) exhibits the lowest rate of intrapod association …

A Phenological Study Of Bat Communities In Southern Mississippi Caves, Zachary Uriah Roth

Master's Theses

Mississippi is generally not known for its caves, and consequently its cave flora and fauna remain largely unstudied. From fall 2010 to winter 2013, we studied the bat populations in the three largest caves in Mississippi. The most common (and only) species found in these caves were Myotis austroriparius and Perimyotis subflavus. I collected monthly data on the number of bats per species, behaviors and locations of the bats within the caves, as well as atmospheric data at selected positions within each cave. All three caves were found to have significant temperature differences between seasons (winterPerimyotis subflavus was found …

The Conservation Genetics Of Two Emydid Turtles: Emydoidea Blandingii And Malaclemys Terrapin, Charlotte Lizana Petre

Master's Theses

Conservation of turtles is complicated by their sensitivity to habitat degradation and overexploitation. I used microsatellites and standard population genetic analyses to explore genetic diversity, population structure, paternity and demographic history in two emydid turtles that are currently experiencing threats to their survival. The Blanding’s turtle, Emydoidea blandingii, has experienced habitat fragmentation throughout its range, and this study focuses on a population in Massachusetts where hatchlings from one population are being translocated to establish a new population. I found evidence of multiple paternity within clutches and found no significant reduction in genetic diversity when comparing the source population and …

The Drosophila T-Box Transcription Factor Midline Functions Within The Insulin/Akt And C-Jun-N-Terminal Kinase Signaling Pathways To Regulate Interomatidial Bristle Formation And Cell Survival, Qichuan Chen

Master's Theses

From a genetic and allelic modifier screen, we report that the Drosophila melanogaster T-box transcription factor midline (mid), a homolog to the human TBX20 gene, interacts with dFOXO within the insulin receptor (InR) and the c-Jun-N-terminal kinase (JNK) signaling pathways to regulate interommatidial bristle (IOB) formation. Previous studies have identified mid’s role in cell fate specification of sensory organ precursor cells in conjunction with the Notch-Delta signaling pathway (Das et al., 2013). The Notch, InR, and JNK signaling pathways regulate dFOXO activity under conditions of stress. Thus, we determined the effects of oxidative stress and metabolic stress by …

Exploring The Glucocorticoid Actions Of 1Α-Hydroxycorticosterone (1Α-Oh-B) In The Elasmobranch Fishes, Faith Nichole Lambert

Master's Theses

The corticosteroid 1α-hydroxycorticosterone (1α-OH-B) is unique to the elasmobranch fishes. It is thought that 1α-OH-B acts as both the primary glucocorticoid (GC) and mineralocorticoid (MC) in these fishes, a dual role analogous to that of cortisol in the teleost fishes. The MC characteristics of 1α-OH-B are well supported, but data supporting its GC functions are lacking. In this study, the putative GC actions of 1α-OH-B were examined. The first experiment characterized the physiological stress response of the Atlantic stingray (Dasyatis sabina) to air exposure, with particular regards to the roles of corticosteroids and metabolic fuels. Results demonstrate that …

Characterization Of The Early Development And Quality Of Red Snapper (Lutjanus Campechanus) Eggs And Larvae In Aquaculture Conditions, Agnès Bardon Albaret

Dissertations

The quality of red snapper Lutjanus campechanus eggs is highly variable and unpredictable in aquaculture, leading to high mortality during early larval rearing. In this work, the viability of red snapper eggs was investigated from fertilization until larvae expired due to exhaustion of vitellin reserves. The studied spawns were obtained via strip spawning wild-caught (n=17) and captive (n=7) females following hormonal induction. The fertilization rate, the hatch rate, and the duration of survival of unfed larvae post hatch were weakly correlated to each other, revealing occurrence of distinct and independent components of egg quality.

Spawns from captive females were characterized …

Clarification Of The Systematics Of The Haploporoidea (Trematoda) With Descriptions Of New Genera And Species, Michael Jay Andres

Dissertations

The superfamily Haploporoidea Nicoll, 1914 comprises two families, the Atractotrematidae Yamaguti, 1939 and the Haploporidae Nicoll, 1914, and the subfamily Cadenatellinae Gibson et Bray, 1982. All members are parasites of the alimentary tract or gall bladder of marine, estuarine, and freshwater herbivorous fishes. Overstreet and Curran (2005a) provided a review of the Haploporidae and recognized four subfamilies, the Chalcinotrematinae Overstreet et Curran, 2005, Haploporinae Nicoll, 1914, Megasoleninae Manter, 1935, and Waretrematinae Srivastava, 1937. In a series of five publications, Blasco-Costa et al. (2009a-e) revised the Haploporinae and erected a fifth subfamily, the Forticulcitinae Blasco-Costa, Balbuena, Kostadinova, et Olson, 2009. The …

Fungal Contribution To Carbon And Nutrient Cycling In A Subtropical Freshwater Marsh, Rong Su

Dissertations

Despite the well-known occurrence of emergent standing litter in freshwater marshes, very little quantitative data is available concerning the functional role and contribution of fungal decomposers to litter decomposition or their impact on ecosystem scale carbon and nutrient cycling. In the present study, microbial respiration and seasonal biomass and production rates of fungal decomposers associated with standing plant litter were examined to assess the quantitative contribution of fungi to both fine scale litter decay processes and large-scale ecosystem carbon flow pathways in a subtropical Typha domingensis and mixed Cladium jamaicense/Juncus roemarianus freshwater marsh, respectively. In addition, the growth …

Online Versus Face-To-Face Biology: A Comparison Of Student Transactional Distance, Approach To Learning, And Knowledge Outcomes, Mary Erin Riggins

Dissertations

Community colleges are among many other institutions increasing course offerings online, but there is still some concern about the quality of online learning. Educator concerns, a lack of empirical evidence on biology courses offered online, and the need for an equal opportunity for education support the need for clarification of the quality of distance education in biology, especially in the community college setting. Student attitudes, approaches to learning, and performance should all be studied in order to formulate a better evaluation of the quality and effectiveness of online courses (Svirko & Mellanby, 2008).

The purpose of this study was to …

Characterization And Role Of Msaabcr In Biofilm Development And Virulence In Staphylococcus Aureus, Gyan Sundar Sahukhal

Dissertations

Community-acquired, methicillin-resistant Staphylococcus aureus strains often cause localized infections in immune-compromised hosts, but some strains show enhanced virulence leading to severe infections even among healthy individuals with no predisposing risk factors. The genetic basis for this enhanced virulence has yet to be determined. S. aureus possesses a wide variety of virulence factors, the expression of which is carefully coordinated by a variety of regulators. Several virulence regulators have been well characterized, but others have yet to be thoroughly investigated. Previously, the msa gene as a regulator of several virulence genes, biofilm development, and antibiotic …

The Influence Of Observational Learning On Self-Reported Physical Activity, Self-Efficacy For Physical Activity, And Health-Related Fitness Knowledge For Physical Activity, Charles Gregory Bullock

Dissertations

The obesity epidemic has caused tremendous burden to our economy and healthcare system. Physical activity is one method that can reduce the obesity rate. However, physical activity declines in high school and does not recover. The likelihood of adolescents continuing their involvement in physical activity depends on how they navigate the highs and lows of their physical activity experiences (Feltz & Magyar, 2006). The purpose of this study is to look at the role of observational learning in physical activity and behaviors in an adolescent population. Specifically, this research examines the influence of observational learning on self-reported physical activity, self-efficacy …

Proceedings Of The 2014 Midsouth Computational Biology And Bioinformatics Society (Mcbios) Conference, Jonathan D. Wren, Mikhail G. Dozmorov, Dennis Burian, Andy Perkins, Chaoyang Zhang, Peter Hoyt, Rakesh Kaundal

Faculty Publications

No abstract provided.

Antiviral Responses In Mouse Embryonic Stem Cells: Differential Development Of Cellular Mechanisms In Type I Interferon Production And Response, Ruoxing Wang, Jundi Wang, Dhiraj Acharya, Amber M. Paul, Fengwei Bai, Faqing Huang, Yan-Lin Guo

Faculty Publications

We have recently reported that mouse embryonic stem cells (mESCs) are deficient in expressing type I interferons (IFNs) in response to viral infection and synthetic viral RNA analogs (Wang, R., Wang, J., Paul, A. M., Acharya, D., Bai, F., Huang, F., and Guo, Y. L. (2013) J. Biol. Chem. 288, 15926–15936). Here, we report that mESCs are able to respond to type I IFNs, express IFN-stimulated genes, and mediate the antiviral effect of type I IFNs against La Crosse virus and chikungunya virus. The major signaling components in the IFN pathway are expressed in mESCs. Therefore, the basic molecular mechanisms …

Genetic Evidence For Multiple Sources Of The Non-Native Fish Cichlasoma Urophtalmus (Günther; Mayan Cichlids) In Southern Florida, Elizabeth Harrison, Joel C. Trexler, Timothy M. Collins, Ella Vazquez-Domínguez, Ulises Razo-Mendivil, Wilfredo A. Matamoros, Christian Barrientos

Student Publications

The number and diversity of source populations may influence the genetic diversity of newly introduced populations and affect the likelihood of their establishment and spread. We used the cytochrome b mitochondrial gene and nuclear microsatellite loci to identify the sources of a successful invader in southern Florida, USA, Cichlasoma urophthalmus (Mayan cichlid). Our cytochrome b data supported an introduction from Guatemala, while our microsatellite data suggested movement of Mayan Cichlids from the upper Yucatán Peninsula to Guatemala and introductions from Guatemala and Belize to Florida. The mismatch between mitochondrial and nuclear genomes suggests admixture of a female lineage from Guatemala, …

Influence Of Resource Levels, Organic Compounds And Laboratory Colonization On Interspecific Competition Between The Asian Tiger Mosquito Aedes Albopictus (Stegomyia Albopicta) And The Southern House Mosquito Culex Quinquefasciatus, D.W. Allgood, Donald A. Yee

Faculty Publications

The mosquitoes Aedes albopictus (Stegomyia albopicta) (Skuse) and Culex quinquefasciatus (Say) (Diptera: Culicidae) are common inhabitants of tyres and other artificial containers, which constitute important peridomestic mosquito breeding habitats. We tested the hypotheses that interspecific resource competition between the larvae of these species is asymmetrical, that the concentration of chemicals associated with decomposing detritus affects the competitive outcomes of these species, and that wild and colonized strains of Cx. quinquefasciatus are affected differently by competition with Ae. albopictus. We conducted two laboratory competition experiments wherein we measured survivorship and estimated population growth (λ′) in both species under …

Molecular Characterization Of Two Opecoelid Trematodes From Fishes In The Gulf Of Mexico, With A Desceiption Of A New Species Of Helicometra, Michael J. Andres, Candis L. Ray, Eric E. Pulis, Stephen S. Curran, Robin M. Overstreet

Faculty Publications

The plagioporine opecoelids Helicometra fasciata (Rudolphi, 1819) Odhner, 1902, and Macvicaria crassigula (Linton, 1910) Bartoli, Bray, and Gibson, 1989 have been reported from fishes in expansive geographic regions, disjointed from their type localities. New material of M. crassigula was collected from near its type locality as well as specimens resembling Helicometra fasciata sensu lato from three triglids in the Gulf of Mexico. Comparisons of the ribosomal DNA (rDNA) sequences, comprising the partial 18S rDNA, internal transcribed spacer region (= ITS1, 5.8S, and ITS2), and partial 28S rDNA gene, from M. crassigula and Helicometra fasciata sensu lato in the Gulf of …

Self-Assembled Gold Nanoplexes For Cancer-Targeted Sirna Delivery, Yongliang Shi

Master's Theses

Through layer-by-layer method, the authors have constructed three Au nanoplexes: AuPEI/RNA/PEI, AuPEI/RNA/PEI-mPEG, and AuPEI/NA/PEI-PEG-FA. All the nanoplexes are characterized by UV-vis spectrometry, DLS, and zeta potential. The surface density of the first layer PEI and second layer RNA were also determined. Moreover, the Au nanoplexes can protect siRNA from RNase degradation and are stable in cell culture medium.

siGLuc-ppp, ssRNA₈₀, and siF17 were delivered by the assembled Au nanoplexes, and the results were analyzed by GLuc assay, TB assay, and Luciferase assay. In terms of RNA delivery, the Au nanoplexes AuPEI/RNA/PEI exhibited excellent gene silencing efficiency (or causing …

Effects Of Water Parameters On Container Mosquito (Diptera: Culicidae) Oviposition And Performance, Stephanie Sue Schelble

Master's Theses

Water body parameters have a considerable effect on the communities that develop within them. In small container habitats like tires, the depth, surface area, and volume effect the development and success of the mosquito communities. This study investigated the choices of the adult female mosquitoes, Aedes albopictus and Culex quinquefasciatus, between different depths and surface areas. In addition, larval performance was determined under differing depth and larvae densities. Oviposition studies showed that Ae. albopictus had a preference for deeper habitats (χ²= 14.2902, p= 0.0139) but did not prefer any surface areas (χ²= 7.2321, p= 0.0649) though …

A Description Of Vocalizations And Their Association With Mouthing Behaviors And Social Context In Bottlenose Dolphins, Tursiops Truncatus, Christina Elyse Perazio

Master's Theses

Dolphin communication is multimodal and incorporates physical behaviors and vocalizations. Dolphins often exchange information with conspecifics using different types of vocalizations, and these vocalizations are sometimes associated with specific behaviors. However, the relationship of vocalization type and mouthing behavior type has not been investigated. This thesis examines simultaneous acoustic and visual recordings of bottlenose dolphins (Tursiops truncatus) to determine the relationship between type of mouthing behavior and type of vocalization (whistle, whistle-squawk, chirp, moan, burst-pulse type A, burst-pulse type B, and click trains). The role of the social context of a mouthing behavior is also evaluated. Data were obtained opportunistically …

The Ontogeny Of Whistle Production In Infant Atlantic Bottlenose Dolphins (Tursiops Truncatus) During The First Thirty Days Of Life, Brittany Leigh Jones

Master's Theses

The manner in which dolphin calves acquire their whistle repertoire is largely unknown. This paper focuses on whistle development in four bottlenose dolphin calves during the first thirty days of life in order to increase our understanding of the early emergence of whistles and whistle-like vocalizations. The acoustic parameters of whistle-type vocalizations (i.e., whistles and whistlesquawks) that coincided with a bubblestream emission from the focal calf and/or its mother were analyzed, as were the behavioral states of the mother-calf pair during the emission of such vocals. Mother and calf whistle rates are inversely related, with the mother whistling more often …

Identification And Characterization Of Msab Gene Involved In Biofilm Formation And Virulence In Staphylococcus Aureus, Amelsaad Elbarasi

Master's Theses

Staphylococcus aureus is an important human pathogen that causes a wide variety of life-threatening infections ranging from minor skin and oral infections to severe infections, such as bacteremia, pneumonia, osteomyelitis, or endocarditis due to the presence and secretion of a large number of virulence factors that are controlled by global virulence regulators in complex networks. Furthermore, S. aureus infections have become a threat to public health because of their high potential to form biofilm, and their ability to resist a wide range of antibiotics has exacerbated further. Therefore, understanding the regulatory networks and developing a drug targeting these networks has …

Characterizing Populations Of Non-Coding Rnas In Karenia Brevis At Different Times Of The Diel Cycle, Scott Boyd Anglin

Master's Theses

Karenia brevis is a mixotrophic, marine dinoflagellate found in the Gulf of Mexico that generates periodic, if not annual, harmful algal blooms (also known as “red tides”) in certain coastal areas. In an effort to better understand the biology of this organism, a functional genomics project has been initiated. As part of that project, it has been determined that a significant number of natural antisense transcripts (NATs) as well as double-stranded RNA (dsRNA) molecules exist within the transcriptome of K. brevis. I hypothesize that the non-coding NATs, similar to microRNAs (miRNAs) in other organisms play a role in regulating …

Role Of Msaa Gene In Regulation Of The Msaabcr Operon And Biofilm Development In Staphylococcus Aureus, Ahmed Alzuway

Master's Theses

Staphylococcus aureus is an important human pathogen that causes wide variety of diseases ranging from chronic biofilm associated infection to acute life threatening infection such as bacteremia, pneumonia, osteomyelitis, or endocarditis, despite the progress with antibiotics used in the treatment of bacterial infections. Furthermore, increased use of prosthetic and indwelling devices in modern medical practices has led to increased infections due to S. aureus. Treating S. aureus infections have become difficult owing to its ability to resist most of the antibiotics; this problem is further exacerbated by ability of MRSA strains to form biofilms. Emergence of community-acquired methicillin resistance …

Effects Of Animal Management Changes On The Activity Budgets And Walking Rates Of Zoo Elephants, Angela Dawn Mackey

Dissertations

The current study aimed to assess the effects of two management strategies, weekly rototilling of the enclosure and the provision of unpredictable foraging opportunities, on the daily behavior of six elephants housed at the San Diego Zoo. Observations took place from January to June 2013 and were conducted throughout a 24- hour period. The study was divided into three phases, each two months in duration. During the first phase (baseline) no changes were made to the current management routine of the elephants. In Phase 2, rototilling of the elephant enclosures was increased from once monthly to once per week, while …

Antiviral Responses In Mouse Embryonic Stem Cells: Differential Development Of Cellular Mechanisms In Type I Interferon Production And Response, Ruoxing Wang

Dissertations

Embryonic stem cells (ESCs) have been recognized as a promising cell source for regenerative medicine. Intensive research over the past decade has led to the possibility that ESC-derived cells will be used for the treatment of human diseases. However, increasing evidence indicates that ESC-derived cells generated by the current differentiation methods are not fully functional. It is recently recognized that ESC-derived cells lack innate immunity to a wide range of infectious agents and inflammatory cytokines. When used in patients, ESC-derived cells would be placed in wounded sites that are exposed to various pathogens and inflammatory cytokines; therefore, their viability and …

Gelatinous Zooplankton Biomass In The Global Oceans: Geographic Variation And Environmental Drivers, Cathy H. Lucas, Daniel O.B. Jones, Catherine J. Hollyhead, Robert H. Condon, Carlos M. Duarte, William M. Graham, Kelly L. Robinson, Kylie A. Pitt, Mark Schildhauer, Jim Regetz

Faculty Publications

Aim

Scientific debate regarding the future trends, and subsequent ecological, biogeochemical and societal impacts, of gelatinous zooplankton (GZ) in a changing ocean is hampered by lack of a global baseline and an understanding of the causes of biogeographic patterns. We address this by using a new global database of GZ records to test hypotheses relating to environmental drivers of biogeographic variation in the multidecadal baseline of epipelagic GZ biomass in the world's oceans.

Location

Global oceans.

Methods

Over 476,000 global GZ data and metadata items were assembled from a variety of published and unpublished sources. From this, a total of …

Identification And Characterization Of An Operon, Msaabcr, That Controls Virulence And Biofilm Development In Staphlococcus Aureus, Gyan S. Sahukhal, Mohamed O. Elasri

Faculty Publications

Background

Community-acquired, methicillin-resistant Staphylococcus aureus strains often cause localized infections in immunocompromised hosts, but some strains show enhanced virulence leading to severe infections even among healthy individuals with no predisposing risk factors. The genetic basis for this enhanced virulence has yet to be determined. S. aureus possesses a wide variety of virulence factors, the expression of which is carefully coordinated by a variety of regulators. Several virulence regulators have been well characterized, but others have yet to be thoroughly investigated. Previously, we identified the msa gene as a regulator of several virulence genes, biofilm development, and antibiotic resistance. We also …

Large Scale Screening Of Digeneans For Neorickettsia Endosymbionts Using Real-Time Pcr Reveals New Neorickettsia Genotypes, Host Associations And Geographic Records, Stephen Greiman, Vasyl V. Tkach, Eric Pulis, Thomas J. Fayton, Stephen S. Curran

Faculty Publications

Digeneans are endoparasitic flatworms with complex life cycles including one or two intermediate hosts (first of which is always a mollusk) and a vertebrate definitive host. Digeneans may harbor intracellular endosymbiotic bacteria belonging to the genus Neorickettsia (order Rickettsiales, family Anaplasmataceae). Some Neorickettsia are able to invade cells of the digenean's vertebrate host and are known to cause diseases of wildlife and humans. In this study we report the results of screening 771 digenean samples for Neorickettsia collected from various vertebrates in terrestrial, freshwater, brackish, and marine habitats in the United States, China and Australia. Neorickettsia were detected using a …

Interspecific Variation In Juvenile Snapper Otolith Chemical Signatures In The Northern Gulf Of Mexico, William F. Patterson Iii, Beverly K. Barnett, Michelle Zapp Sluis, James Howan Cowan Jr., Alan M. Shiller

Faculty Publications

The objective of this study was to evaluate whether age-0 lane snapper Lutjanus synagris otolith chemical signatures could serve as accurate proxies for those of its congener, red snapper L. campechanus, among northern Gulf of Mexico (GOM) nursery regions. Red (n = 90) and lane (n = 53) snappers were sampled from 3 regions of the northern GOM in fall 2005, and their otolith chemistry was analyzed with sector field-inductively coupled plasma-mass spectrometry (Ba:Ca, Mg:Ca, Mn:Ca, Sr:Ca, Li:Ca) or stable isotope ratio-mass spectrometry (δ¹³C and δ¹⁸O). Chemical signatures were significantly different among regions (MANOVA, p < 0.001) and between species (MANOVA, p = 0.029), with the species effect being driven by significant differences in 4 of the 7 constituents analyzed (ANOVA, p < 0.036). The significant region effect persisted (MANOVA, p < 0.001), but the species effect was non-significant (MANOVA, p = 0.964) when constituent values were normalized to species-specific means. Mean regional classification accuracies from linear discriminant functions computed with otolith constituent data were 84% for lane snapper and 80% for red snapper whether data were normalized or not. Maximum likelihood models parameterized with normalized lane snapper otolith chemistry data estimated red snapper regional composition reasonably well among mixed-region samples (mean error = 9.7% among models). Therefore, it appears age-0 lane snapper otolith chemical signatures can serve as accurate proxies for those of red snapper in the northern GOM. These results have broader implications for deriving natural tags based on otolith chemistry for fishes that may have low abundance in parts of their range.