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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Mapping Tampa Bay <em>Cynoscion nebulosus</em> Spawning Habitat Using Passive Acoustic Surveys

Walters, Sarah Lyle 19 October 2005 (has links)
Spotted seatrout, Cynoscion nebulosus, spawning locations as well as associated environmental variables were determined for Tampa Bay, Florida during the 2004 spawning season using a mobile hydrophone survey. Hydrophones, a type of underwater microphone, can be used to detect and record spawning sounds of soniferous fishes. During their spawning season in Tampa Bay which generally occurs between March and September, mature male spotted seatrout generate sounds associated with courtship in the crepuscular and evening periods by vibrating sonic muscles against the swim bladder. Active spawning sites can be located using hydrophones to find these calling males. Using a random stratified sampling method, 760 stations within Tampa Bay (46 % of the sampling universe) were sampled over the 2004 spawning season. Only 8% of sampled stations had large aggregations of spotted seatrout. Spawning, determined by the sound produced by large aggregations, was detected throughout the bay except for Hillsborough Bay and was most common in the lower bay and eastern region of the middle bay. Presence of submerged aquatic vegetation (SAV), proximity to shoreline, as well as high dissolved oxygen values and shallow depth were positively correlated with spawning areas. Courtship calls of sand seatrout, Cynoscion arenarius, and silver perch, Bairdiella chrysoura were also detected during the survey as they share an overlapping spawning season with spotted seatrout. Aggregations of all three species rarely occurred simultaneously. Sand seatrout and silver perch used different habitats within Tampa Bay to spawn and spawned with a much greater frequency than spotted seatrout. Courtship calls of spotted seatrout were analyzed both by ear and by received sound level to determine if signal processing could be used to assess courtship sound recordings. However, there was no clear relationship between the two methods.
112

Ontogenetic Diet Shifts and Prey Preference of a Generalist Predatory Fish

Scharf, Brittany Jalene 20 July 2014 (has links)
Marine ecosystems are highly dynamic and contain a diverse faunal assemblage that are subject to various natural and anthropogenic variability. Globally, seagrass ecosystems are located adjacent to coastal areas that are heavily impacted by human development and urbanization potentially altering the community structure within these ecosystem. Complex food webs connect many components of these systems, often in unexpected ways, and are ultimately based on one of two pathways: benthic (i.e., seagrass, epiphytes, microalgae, detritus) and planktonic (i.e., phytoplankton). Understanding the pathway which the food web is based gives further insight regarding the biological balance of the ecosystem; thus it is important to expand beyond bounds of single-species approaches for research and management. Observing what a predator consumes and its preference for any particular prey can be informative in regards to how a predator interacts and utilizes an ecosystem. Predatory fish are exposed to a wide range of potential prey with varying levels of mobility in their natural environment and may employ a wide range of feeding tactics in order to capture prey. Overall, prey availability and abundances are influenced by many factors (e.g., seasons, tides, habitat loss and gain) and many piscivorous fishes will undergo ontogenetic shift in diet in order to optimize their energetic return limiting the interpretation of electivity studies. Although much information can be obtained through stomach analysis of fish, some prey are more rapidly digested due to the lack of hard, external structures and may be overlooked in the analysis. Furthermore, prey preference cannot be based solely on the observed abundance in the diet of a predator because it takes time for a predator to find, consume, and digest prey (i.e., "handling time"). Therefore, multiple approaches, both observational and experimental, are necessary to fully understand trophodynamics of fishes and their ecosystems. To better understand the trophodynamics of the Spotted Seatrout, Cynoscion nebulosus, my thesis incorporates both an observational and experimental study. My observational study compares three stomach analyses datasets to address changes in the diet composition over a thirty-two year timespan during which natural and anthropogenic changes potentially altered the community structure of Tampa Bay. This is paired with an experimental study to address differently handling times of two morphologically- and behaviorally- different prey that were observed in the diet of juvenile Spotted Seatrout.
113

Effects of an nC24 agricultural mineral oil on tritrophic interactions between French bean (Phaseolus vulgaris L.), two-spotted mite (Tetranychus urticae Koch) and its predator, Phytoseiulus persimilis Athias-Henriot.

Xue, Yingen, University of Western Sydney, College of Health and Science, School of Natural Sciences January 2007 (has links)
A comprehensive evaluation of the effects of an nC24 agricultural mineral oil (AMO) on tritrophic interactions between French bean Phaseolus vulgaris cv. Redlands Pioneer [Fabales : Fabaceae ], two spotted mite (TSM) Tetranychus urticea Koch [Acari: Tetranychidea] and the predatory mite Phytoseiulus persimilus Atheus-Henriot [Acari: Phytoseiidae] was conducted under laboratory conditions. / Doctor of Philosophy (PhD)
114

Effects of exposure to Eurasian Milfoil (Myriophyllum spicatum) on the growth and development of Xenopus laevis and the Columbia spotted frog (Rana Lutriventris)

King, Kimberly L. P., January 2007 (has links) (PDF)
Thesis (M.S. zoology)--Washington State University, December 2007. / Includes bibliographical references (p. 24-26).
115

The management of spotted alfalfa aphid, Therioaphis trifolii (Monell) f. maculata, in dryland lucerne pasture in South Australia

Allen, P. G. (Peter Gordon), 1941- January 1984 (has links) (PDF)
Mounted ill. Bibliography: leaves 263-265.
116

MODIFIED INDIVIDUAL-LEVEL MODELS OF INFECTIOUS DISEASE

Fang, Mingying 15 September 2011 (has links)
Infectious disease models can be used to understand mechanisms of the spread of diseases and thus, may effectively guide control policies for potential outbreaks. Deardon et al. (2010) introduced a class of individual-level models (ILMs) which are highly flexible. Parameter estimates for ILMs can be achieved by means of Markov chain Monte Carlo (MCMC) methods within a Bayesian framework. Here, we introduce an extended form of ILM, described by Deardon et al. (2010), and compare this model with the original ILM in the context of a simple spatial system. The two spatial ILMs are fitted to 70 simulated data sets and a real data set on tomato spotted wilt virus (TSWV) in pepper plants (Hughes et al., 1997). We find that the modified ILM is more flexible than the original ILM and may fit some data sets better.
117

THE FATTY ACID-BINDING PROTEIN (fabp) GENES OF SPOTTED GREEN PUFFERFISH (TETRAODON NIGROVIRIDIS) - COMPARATIVE STRUCTURAL GENOMICS AND TISSUE-SPECIFIC DISTRIBUTION OF THEIR TRANSCRIPTS

Thirumaran, Aruloli 04 December 2013 (has links)
The fatty acid-binding protein (fabp) genes belong to the multigene family of intracellular lipid-binding proteins (iLBP). To date, 12 different FABPs have been identified in various vertebrate genomes. Owing to the fish-specific whole genome duplication (FSGD) event, many fishes have duplicated copies of the fabp genes. Here, I identified and characterized the fabp genes of spotted green pufferfish (Tetraodon nigroviridis). Initially, a BLAST search was performed and ten fabp genes were identified, out of which, three were retained in the pufferfish genome as duplicated copies. The putative pufferfish Fabp proteins shared greatest sequence identity and similarity with their teleost and tetrapod orthologs. Conserved gene synteny was evident between the pufferfish fabp genes and human, zebrafish, three-spined stickleback and medaka FABP/fabp genes, providing evidence that the duplicated copies of pufferfish fabp genes most likely arose as a result of the FSGD. The differential tissue-specific distribution of pufferfish fabp transcripts suggests divergent spatial regulation of duplicated pairs of fabp genes.
118

The management of spotted alfalfa aphid, Therioaphis trifolii (Monell) f. maculata, in dryland lucerne pasture in South Australia / by P.G. Allen

Allen, P. G. (Peter Gordon), 1941- January 1984 (has links)
Mounted ill. / Bibliography: leaves 263-265 / 265 leaves [1] leaf of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agriculture, 1984
119

Tetranychus urticae (Acarina: teranychidae)'nin üç farklı insektisit-akarisit ile seleksiyonundan sonra çoklu direnç ve bazı enzim düzeylerinin incelenmesi /

Yorulmaz, Sibel. Ay, Recep. January 2008 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Bitki Koruma Anabilim Dalı, 2008. / Bibliyografya var.
120

Effects of color to deter thrips and reducing the incidence of tomato spotted wilt virus

Kelley, Mallory Jones, Foshee, Wheeler G., January 2009 (has links)
Thesis--Auburn University, 2009. / Abstract. Vita. Includes bibliographical references.

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