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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.
101

Geoexplorer : A free open-source framework for black-box testing and scraping information from geographic services

Hanssen Seferidis, Johan January 2013 (has links)
This is a report on the development of a free open-source framework. The framework is meant to be used to mainly black-box test and/or scrape information from a geographic service like Google Places, Facebook Places or Foursquare. In reality any service that is based on geographic coordinates can be used with the framewok. Amongst others, the framework offers functionalities like visualisation on-the-fly and logging of different aspects of the service. There are a few similar tools scattered on the world-wide web, but they usually are hard to find and if they are found, they either are not open-source, free or they lack in functionality. Another major drawback is that the available solutions are very generic, and thus limiting their capabilities. The work described here is an attempt for a concise, easy to use, extendible framework solely focused on geographic services. In this report, the technologies used are demonstrated, while at the same time the reasons are given as to why a specific technology was selected in each case. Some documentation is also presented and a few references to the actual code-base in case someone wants to extend Geoexplorer or use it at their organization.
102

Feeding behaviour of Ateles belzebuth E. Geoffroy 1806 (Cebidae: Atelinae) in Tawadu Forest southern Venezuela

Amoroso, Castellanos Hernan Gerardo January 1995 (has links)
No description available.
103

Langmuir films and nanoparticle applications of a spider silk protein analog

Davidson, Patricia Marie L. January 2006 (has links)
A synthetic analog of a spider silk protein (M4) was studied. Langmuir films were made and an inflexion in the isotherm indicated conformational changes upon compression. Deposition onto solid substrates was most successful using a hydrophobic substrate and the Langmuir-Schaeffer method. AFM was used to image the surface, which was mesh like and did not show any indication of order. / Gold nanoparticles were produced in the presence of the protein and protein solutions were added to read made nanoparticles for the purpose of displacing the weak ligands present. CD measurements were performed on the protein solutions to study its conformation. Nanoparticle size information was obtained from TEM images. DLS was used to determine if the protein was affected by the addition of the gold nanoparticles. Precipitation of the protein was shown not to affect the nanoparticles.
104

Propagation and biology of arachnorchis (orchidacae) and their mycorrhizal fungi

Raleigh, Ruth Elizabeth, Ruth.e.raleigh@dse.vic.gov.au January 2006 (has links)
Terrestrial orchids make up one of the most threatened groups of plants in Australia and the genus Arachnorchis is listed as the fourth most threatened. The process of propagation and re-introduction of terrestrial orchid plants to the wild has proven difficult, and so far, nearly impossible for some species. This may be partly because terrestrial orchids form complex relationships with mycorrhizal fungi and in genera like Arachnorchis the dependency on the fungus appears acute. Arachnorchis has long been considered by amateur growers of terrestrial orchids as one of the most difficult groups to propagate and maintain in cultivation. This lack of knowledge on how to grow Arachnorchis species hinders attempts made by conservation authorities to supplement threatened wild populations in order to achieve a more sustainable future for those species. Natural pollination was absent, but artificial pollination achieved 100% capsule production. Individuals were self-fertile, although seed viability was greater for cross-pollinated samples. This study attempted to track the fate of as many Arachnorchis species as possible from germination through to deflasking and re-emergence, and so destructive and potentially destructive measurements at earlier stages were avoided. This thesis examines germination and subsequent growth of up to eight species of Arachnorchis, but concentrated on A. phaeoclavia, A. tentaculata, A. fulva, A. robinsonii and A. venusta. Two of these are common species: A. pha eoclavia and A. tentaculata, and three carried a threatened classification of &quotrare" or " endangered": A. fulva, A. robinsonii and A. venusta. This study monitored the fate of individuals of the endangered A. fulva in the field and showed that large reproductive plants re-emerged and flowered each year, whereas smaller individuals might be absent in one or more years and were less likely to flower. Germination of all species concentrated on using symbiotic culture (using mycorrhizal fungi), since germination is known to be more rapid, resulting in healthier, more robust seedlings than when plants are grown asymbiotically. Tests using A. fulva and A. venusta, two threatened species, showed similar viability to A. tentaculata and A. phaeoclavia, more common species. Germination was maximised by examining the viability of seeds before and after treatment with surface-sterilising solutions required for aseptic culture. The highest levels of germination, with limited contamination, were achieved using 0.5% available chlorine for 3 minutes. The most effective fungal isolates (&gt65% germination) were obtained from common species like A. phaeoclavia and A. tentaculata, but there was no correlation between germination and time of year or life stage of the orchid. Collar collection was shown to be non-fatal to robust orchid plants, with large reproductive individuals (at the time of collar collection) re-emerging in the next year and producing a flower bud. Collar collection from small, weedy individuals could be fatal to the plant and isolation of an effective fungus was unlikely. Cross-inoculating seeds with fungi isolated from a different orchid species was not recommended, since the symbiosis failed in all experiments, as late as Stage 4 protocorm development. A range of substrates was used to produce strong seedlings capable of surviving the transfer to nursery conditions with minimal loss. More than 81% of seedlings survived deflasking from non-agar substrates, while the best result from agar was 55%. Some substrates reduced the time involved from seed to plants in the field to as little as 4 months, but aftercare became critical. Sucrose promoted tuberisation, but led to tuber deaths during dormancy. Potting mixes were tested in the nursery and a free-draining loam mix based on a mix used by the Australasian Native Orchid Society was the best medium for deflasking of seedlings. Watering during dormancy should be avoided. The choice of propagule for re-introduction was examined and the best survival to re-emergence was obtained by planting out actively growing seedlings in autumn. Identification of cultures using classical morphology grouped cultures as belonging to the form-genera Epulorhiza and Moniliopsis and suggested that most cultures contained more than one fungus. Identification of the most useful fungal cultures was attempted using molecular techniques such as sequencing the ITS region and mitochondrial DNA. One effective culture, CALAPHAER18 SHTX (cultured from a single monilioid cell) was identified as Serendipita vermifera (Oberwinkler) Roberts. All other cultures tested were mixtures of fungi. The use of specific primers designed to amplify a sequence present in the identified isolate (CALAPHAER18 SHTX) showed that nine mixed cultures also contained a fungus most closely related to Serendipita vermifera. Specific primers also showed that Rhizoctonia solani was not present in any of the 10 isolates from Arachnorchis plants. The molecular work showed that, although the sequenced endophytes from Arachnorchis were all most closely related to Serendipita vermifera, three dist inct groups of fungi were present and these associated with separate species of Arachnorchis. Future work with Arachnorchis species will require the isolation of single fungus cultures and further examination of the development of the orchid plant. In particular, the process of tuberisation and growth in vitro on various non-agar substrates should be investigated further.
105

The population dynamics of a riparian spider: interactive effects of flow-related disturbance on cross-ecosystem subsidies and spider habitat

Greenwood, Michelle Joanne January 2007 (has links)
The transfer of prey resources between ecosystems can have dramatic consequences for both recipient and donor systems by altering food web stability and the likelihood of trophic effects cascading across the ecosystem boundary. Landscape-scale factors influence the importance, direction and magnitude of energy flows, but may also alter the ability of consumer organisms to respond to spatio-temporal changes in allochthonous prey availability. Here, I used flood and drying disturbance gradients to investigate interactions between these two processes on populations of a riparian fishing spider Dolomedes aquaticus (Pisauridae). The abundance of aquatic insects with a winged adult stage, a major component of the diet of D. aquaticus, was markedly higher at less flood-prone rivers and declined with increasing flood disturbance. It was expected that spider populations would be largest at these stable rivers where the aquatic prey abundance was highest. However, a habitat (loose, unembedded riverbank rocks) manipulation revealed that the lack of scouring floods at these sites led to habitat-limited populations, preventing response to the increased prey resource. In fact a peak shaped relationship of spider biomass and abundance was found, with the largest spider populations at intermediately disturbed rivers. In addition, patchy habitat availability was the most likely cause of the small scale (4 m2) aggregation of spiders seen at the most stable and disturbed rivers. These patterns were also associated with strong interactions between the spiders. Stable isotope analysis of field collected spiders and an experimental manipulation of spider densities and food availability indicated that cannibalism rates were likely to be significantly higher at stable and disturbed rivers than those intermediate on the disturbance gradient. Differences in D. aquaticus population size structure and life history traits across the flood disturbance gradient were driven by interactions between resource availability, environmental stability and cannibalism rates. To separate the effects of habitat availability and aquatic prey abundance I used drying rivers, as the amount of aquatic insect prey alters as the water recedes. Desiccation mortality and low aquatic prey biomass most likely caused the spiders' spatial distribution and size class structure to alter in drying river reaches, potentially also leading to differences in cannibalism rates. Overall, cross-ecosystem transfers of prey had large impacts on the distribution, cannibalism rates and life history traits of D. aquaticus but their effects were modified by the nature of the ecosystem boundary. Thus river flow regime controlled the magnitude of the subsidy and its use by a consumer. Hence, cross-ecosystem subsidies will not always lead to larger consumer populations and consumer responses will depend on interactions between large-scale processes.
106

Algal Preferences in the Masking Behaviour of the Spider Crab, Notomithrax ursus

Ertel, Catherine Monica January 2008 (has links)
The purpose of this study was to examine the masking preferences of the spider crab, Notomithrax ursus. The algal composition of the mask in the natural habitat at Kaikoura was examined to determine the general rules the crab follows when decorating itself. The effects of size and sex on the mask composition were examined, as well as determining how the composition of the mask varies by body part. The preference of the crabs was further examined through the use of choice and background change experiments in the laboratory. It was determined that the preference of certain types of algae for mask material is not entirely dependent on their relative abundance in the environment. Possible explanations for this behaviour are given.
107

Aspects of the biology of the ladybird beetle Stethorus vagans (Blackburn) (Coleoptera: Coccinellidae) /

Khan, Inamullah. January 2000 (has links)
Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2000. / "A thesis presented in fulfilment of the requirement for the degree of Doctor of Philosophy" Bibliography : leaves 160-183.
108

Efficacy of botanical and mineral oils on Willamette mite (Acari: Tetranychidae) : a thesis /

Church, Elizabeth Ruby Begonia. Costello, Michael J. January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page, viewed on March 30, 2009. Major professor: Michael J. Costello, Ph.D. "Presented to the Electrical Engineering Department Faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture, with specialization in Plant Protection Science." March 2009." Includes bibliographical references (p. 48-54). Will also be available on microfiche.
109

Clofentezine, fenpyroximate ve amitraz ile seleksiyon yapılmış tetranychus urticae koch populasyonlarının direnç, çoklu direnç, direnç kalıtımının ve bazı enzim düzeylerinin belirlenmesi /

Kara, Fatma Ebru. Ay, Recep. January 2008 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Bitki Koruma Anabilim Dalı, 2008. / Bibliyografya var.
110

Conformational Fluctuations of Biomolecules Studied Using Molecular Dynamics and Enhanced Sampling

Gray, Geoffrey M. 06 April 2018 (has links)
Biomolecule structural fluctuations determine function, regulating numerous biological processes My research has shed light on several interesting cases in which structural fluctuations have been identified to assess functional differences. Chapter 2 discusses the effects of structural rearrangement of the β2-β3 loop on the DNA binding affinity of the type 6 human papillomavirus E2 protein. Chapter 3 investigates the effects of phosphorylation on the C-terminal domain of Cdc37, a protein important in the Hsp90 chaperone cycle. Chapter 4 studies the effects on cyclycization on the conformational fluctuations of a γ-AApeptide used for high-throughput libraries. Chapter 5 is a structural study on a mini-fibril of spider dragline silk, in which a native-like ensemble was generated using temperature replica exchange. Chapter 6 investigates the structural features of repetitive motifs found in spider dragline silk when subject to both dope-like and fiber-like conditions. Chapter 7 elucidates conformational differences between the RXRα and the RXRβ ligand-binding domains and seeks to understand the atomic basis for different ligand binding affinities. This body of work has contributed to the understanding of conformational fluctuations and changes that occur in protein-DNA binding systems, drug-binding, regulation of chaperones via post-translations modifications and spider dragline silk.

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