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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.
141

Studies on the arrested development of Haemonchus contortus (Rudolphi, 1803), Nematoda, in sheep.

Blitz, Nicolas Martin. January 1970 (has links)
No description available.
142

Aspects of biogenic amines and the nervous system in a parasitic nematode, Phocanema decipiens.

Goh, Soon Leong January 1975 (has links)
No description available.
143

Seasonal fluctuations of nematode populations inhabiting the gastrointestinal tract of breeding ewes and lambs.

Ayalew, Liyew. January 1969 (has links)
No description available.
144

The impact of demersal fishing on marine soft-sediment meiofauna

Harries, Daniel Bernard January 1995 (has links)
No description available.
145

Characterization of tubulins from parasitic nematodes (Brugia malayi, B. pahangi and Nippostrongylus brasiliensis) and comparison with mammalian brain tubulin

Tang, Liang January 1988 (has links)
The properties of tubulins from Brugia malayi, B. pahangi, Nippostrongylus brasiliensis and rat brain were compared. Tubulins from all nematodes and rat brain were partially purified by polylysine agarose chromatography, those of brain also by cycles of assembly/disassembly, and all by taxol-induced assembly. The tubulins were compared with respect to concentration ($ mu$g tubulin/mg soluble protein), drugs binding and isoforms. The tubulins of B. malayi and B. pahangi were similar. However, the tubulin from these filariae were different from those of N. brasiliensis. Even larger differences were detected between the nematode tubulins and those of rat brain. However, all tubulins reacted to $ alpha$- and $ beta$-tubulin monoclonal antibodies, and had similar mobility on SDS-PAGE. Different peptide maps were obtained for N. brasiliensis tubulin compared with rat brain tubulin. Tubulins of N. brasiliensis bound more mebendazole than did those of Brugia nematodes (B$ sb{ rm max}$: pmoles/$ mu$g tubulin). The binding of benzimidazoles to nematode tubulins was much higher than to rat brain tubulin. Benzimidazole binding to brain tubulin was influenced by the degree of assembly of the tubulin. This did not appear to be the case for the nematode tubulins. In vitro translation of B. malayi mRNA resulted in two isoforms for both $ alpha$- and $ beta$-tubulins in contrast to the 4 $ alpha$- and 4-5 $ beta$-isoforms found naturally. This suggest post translational modification of tubulin may take place in B. malayi. This study has characterized some of the differences that exist between mammalian tubulins and those of nematodes on the one hand, and between the tubulins of a gastrointestinal nematode (N. brasiliensis) and those of filariae (B. malayi and B. pahangi) on the other hand.
146

The ecology of free-living nematodes in nearshore marine and estuarine sediments of the microtidal lower west coast of Australia.

m.hourston@iinet.net.au, Mathew Hourston January 2009 (has links)
The overarching aim of this thesis was to describe the ecology of the assemblages of free-living nematodes in the sediments of nearshore marine and estuarine waters on the microtidal lower west coast of Australia. The thesis also provides descriptions of ten previously undescribed species as well as develops and tests a habitat classification scheme for the Swan River Estuary using these biotic assemblages. The first section of my thesis has determined the ways in which the characteristics of the nematode assemblages in nearshore marine waters along the microtidal lower west coast of Australia are related to habitat type, time of year and shore-perpendicular zones. Three habitat types, which had previously been identified on the basis of a suite of enduring environmental characteristics, could be broadly described as highly sheltered from wave activity and containing dense seagrass (habitat type 1), moderately sheltered from wave activity and with sparse seagrass (habitat type 2) and relatively exposed to wave activity and with no seagrass (habitat type 6). Sampling in five consecutive seasons yielded > 15 000 nematodes, representing 75 species. The number of species and densities in habitat type 1, and particularly those in its subtidal zone, were far greater than those in the other two habitat types. Both of these biotic variables underwent marked seasonal changes, declining to low levels during winter. The compositions of the assemblages differed significantly among the three habitat types, with the differences between habitat types 1 and 6 being particularly marked. Paracomesoma sipho, Dichromadora sp., Marylynnia annae and Pomponema sp., which, on the basis of their buccal cavity morphology, are assumed to feed primarily on benthic diatoms, were particularly abundant at the most sheltered habitat type, whereas Gonionchus australis, Theristus sp. and Bathylaimus australis, which are assumed to be deposit feeders, were relatively abundant at the most highly exposed habitat type. The compositions of the assemblages differed among seasons and were most discrete in spring, due to marked increases in the densities of certain species. However, differences in the compositions in the different zones of each habitat type were relatively small, presumably reflecting the influence of the small tidal regime of this region. The second component of this thesis has determined the ways in which the density, number of species, species composition and trophic structure of free-living nematode assemblages in the subtidal waters of a large microtidal estuary change spatially and temporally, and has explored whether those four biotic characteristics are related to certain environmental factors. Based on data derived from samples collected seasonally at 12 sites throughout the estuary, the densities and number of species of nematodes decreased progressively with distance from estuary mouth, to reach a minimum at sites where salinities were most variable, and then increased slightly in the uppermost part of the estuary where salinities were least. Densities were also generally greatest in spring, due largely to increases in the abundance of epistrate-grazing species at the time when the amount of primary food (microphytobenthos) peaked. The spatial distribution of the composition of the nematode assemblages was closely correlated with salinity and, to a lesser extent, grain-size composition and amount of particulate organic material in the sediment (%POM). Although species composition changed sequentially along the estuary, the change was particularly pronounced between sites above and below the area where salinities started to decline markedly and become more variable and %POM increased markedly. This reflected, in particular, far greater abundances of Spirinia parasitifera at the six downstream sites, and of Theristus sp. 1 at the six sites further upstream. Species composition underwent pronounced seasonal cyclical changes at all sites, presumably reflecting interspecific differences in the timing of peak reproduction and thus of recruitment. The trophic structure of the nematode assemblages changed both spatially and temporally in relation to the relative abundance of different food sources. Thus, for example, non-selective deposit feeders, such as Theristus sp. 1, dominated samples in the upper estuary, where %POM was by far the greatest, and was rare or absent at downstream sites. Conversely, epistrate grazers, such as species of the Chromadoridae, were most abundant at downstream sites in spring, when the density of the microphytobenthos reached its maximum. The data for the nematode assemblages in nearshore subtidal marine sediments of the lower west coast of Australia were compared with those in nearshore subtidal sediments in the upper and lower regions of the Swan River Estuary. The densities and average species richness in cores from the marine environment were much lower than in cores from both estuarine regions. However, the total number of species found in the marine environment was much greater than in the estuary. The compositions of the nematode assemblages were more variable in marine than estuarine sediments. The assemblages from the two estuarine regions were far more similar to each other than to those from the marine region at a species level, and also, but to a lesser extent, at the generic and family levels. While the trophic compositions of the nematode assemblages in the upper estuarine region was dominated by non-selective deposit feeding species and those of the lower estuarine region were dominated by epistrate grazing species during spring and non-selective deposit feeding species in other seasons, the dominant functional feeding groups varied among the sites representing the marine region. That variability presumably reflects differences in the relative contributions of the different potential food sources. Surprisingly, the trophic composition in the upper estuarine region, i.e. comprising predominantly non-selective deposit feeders, was similar to that at the very different environment of the most exposed marine site. The dominance of this feeding group at the marine site is assumed to be attributable to the fact that the only food source of any note is POM and, even then, it occurs in only small amounts. Taxonomic descriptions have been produced for ten new species of nematodes found during the ecological studies of the free-living aquatic nematofaunas of south-western Australia. These species were chosen because they were members of families for which the other species had been described and, in a number of cases, were important for distinguishing between the compositions of a priori groups. They comprised four species of Axonolaimidae, representing the genera Ascolaimus, Parascolaimus, Odontophora and Parodontophora, and six species of Desmodoridae, representing single species of Bolbonema, Eubostrichus, Catanema and Leptonemella and two species of Onyx. As a complement to the nematological study of the Swan River Estuary, a novel habitat classification system was developed and then applied in this environment. This system was based on enduring environmental characteristics and employed the relatively new multivariate statistical routines SIMPROF and LINKTREE. The applicability of habitat types produced by this classification system to biotic assemblages was tested using the data for the estuarine nematode assemblages described above. The results demonstrate that the compositions of the assemblages differed significantly among each of the habitat types defined by the classification system. While there were also significant differences between the compositions of the nematofaunas at sites belonging to the same habitat type, the extent of these differences were generally less than those between habitat types. A significant and strong correlation was also found between the spatial pattern exhibited by the environmental characteristics used to define habitat types, and that of the nematofauna.
147

Investigations to develop methods to control the nematode associated with annual ryegrass toxicity /

McKay, A. C. January 1985 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Plant Pathology, 1985. / Some ill. mounted. Includes bibliographical references (leaves 145-160).
148

Isolation and characterisation of novel non-ribosomal peptide synthetase genes from the entomopathogenic Xenorhabdus bovienii T228 /

Pinyon, Rebecca A. January 2002 (has links) (PDF)
Thesis (Ph.D) -- University of Adelaide, Dept. of Molecular Biosciences, 2002. / Bibliography: leaves 363-381.
149

Adaptation to temperature in entomopathogenic nematodes /

Jagdale, Ganpati Baburao, January 1997 (has links)
Thesis (Ph. D.)--Memorial University of Newfoundland, 1997. / Bibliography: leaves 167-188.
150

A new nematode parasite of mole crickets its taxonomy, biology and potential for biological control /

Nguyen, Khuong Ba, January 1988 (has links)
Thesis (Ph. D.)--University of Florida, 1988. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 149-153).

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