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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.
31

The mechanism of transmission of non-persistent viruses by aphids /

Garrett, Ronald George. January 1971 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Plant Pathology, 1975?
32

Studies of transmission of virus by Culicoides (Ceratopogonidae: Diptera)

Lee, Vernon H. January 1962 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 87-92).
33

Parity of mosquitoes trapped by methods used for arbovirus surveillance

Morris, Charlie Dixon, January 1969 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
34

The biology and vector potential of North American Haemaphysalis ticks

Javidpour, Iraj, January 1965 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1965. / Abstracted in Dissertation abstracts, v. 25 (1965) no. 10, p. 5533. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
35

Die Rolle der Nagetiere als Reservoire und Verbreiter der Pest

Erdmann, Georg Hans, January 1953 (has links)
Inaug. Diss.--Frankfurt am Main. / Lebenslauf. Bibliography: leaves xii-xx.
36

Pharmaceutical eutectics : characterization and evaluation of tolbutamide and haloperidol using thermal analytical and complementary techniques

Gebremichael, Ermias. January 2010 (has links)
Thesis (M.S.)--University of Toledo, 2010. / Typescript. "Submitted to the Graduate Faculty as partial fulfillment of the requirements of the Master of Science degree in Pharmaceutical Sciences with Industrial Pharmacy Option." "A thesis entitled"--at head of title. Title from title page of PDF document. Bibliography: p. 87-102.
37

Optical spin valve effects

Huang, Biqin. January 2007 (has links)
Thesis (M.E.E.)--University of Delaware, 2007. / Principal faculty advisor: Ian Appelbaum, Dept. of Electrical and Computer Engineering. Includes bibliographical references.
38

The influence of abiotic factors on the distribution of Biomphalaria pfeifferi (Krauss, 1848) (Planorbidae: Mollusca) and its lifecycle in South-Eastern Africa

Appleton, Christopher Charles January 1976 (has links)
Previous studies on the influence of abiotic factors on the distribution of bilharzia intermediate host snails of the family Planorbidae are reviewed. Much of this work is basically descriptive and relatively few attempts have been made to examine the effects of these factors on snails in their natural habitats - to identify the factors precisely and to measure their critical levels. An account is given of recent studies on Eiomphalaria pfeifferi (Krauss) in two climatically different regions of southeastern Africa, at 6S5m altitude on the eastern Transvaal escarpment and 19m on the coastal peneplain of northern Zululand. These have shown the species to undergo a similar annual life-cycle of three overlapping generations in both areas. Further, in these areas where the snail has a discontinuous distribution, two abiotic factors, stream geology and water temperature, were found to be important in limiting its distribution. The longitudinal distribution of B. pfeifferi and another host snail Bulinus (Physopsis) globosus (Morelat), extended upstream in a perennial watercourse, the Gladdespruit, on the escarpment only as far as permanently lentic habitats were available. These habitats, usually detached from the channel, characterized the stream's lowest physical zone with its substratum of exposed granite, as opposed to the sandy-bottomed lotic zones upstream. The limit of the snails' occurrence lay close to the junction of these two substratum types. Granite is resistant to erosion but contains soft inclusions which erode more quickly than the hard matrix causing uneven weathering. This results in the formation of depressions in the stream bed (i.e. pools, potholes and backwaters) which provide the permanently lentic conditions necessary for the snails' survival. Temperature recordings made on this plain, upstream of the snails' limit, suggest that the water temperature here exceeded the critical lower levels required for a positive intrinsic rate of natural increase sufficiently often to permit the species to survive here, though not optimally. Above this point however, current velocities are continually in excess of the maximum tolerated (0.3 m/sec.) so that in this situation at least, current velocity is a dominant factor. A contrasting situation exists on the coastal peneplain of northern Zululand where B. pfeifferi occurs in some lentic habitats and not in others. This discontinuous distribution is shown to be related to the prolonged duration of temperatures above the level for optimal increase. The apparently suitable habitats from which B. pfeifferi was absent were found to be both very shallow and to experience these prolonged high temperatures during spring and early summer. This corresponds to the maturation period of the B. pfeifferi 1st generation as defined by Appleton (1974) and causes reduced fecundity probably through impaired gonad development. The density of its filial (2nd) generation is correspondingly reduced. A statistically significant partial-correlation (at a 1% level) was found between the fecundity of the 1st generation and increasing periods of temperatures above the species' optimal limit in the habitats involved during its maturation period (spring). It is interesting to nate here that B. (Ph.) globosus, which is known to be better adapted to high temperatures than B. pfeifferi (Shiff & Husting, 1966) occurred in all the waterbodies concerned. Both these factors therefore play important roles in determining the country-wide distribution pattern of the host snails. This distribution is closely correlated with the availability of permanently lentic habitats. In river systems, which form the main environment for these snails, such stable habitats occur almost entirely in low-gradient reaches over hard bed-rock which is resistant to erosion. Current velocities above 0.3 m/sec. render steeper reaches and those over soft, non-resistant rock and sand (unstable substrata) unsuitable and therefore constitute a most important limiting factor. Temperature however becomes a dominant factor in permanently lentic waterbodies. Biomphalaria pfeifferi is adversely affected by high temperature regimes and where such regimes occur in waterbodies which are too shallow to permit temperature gradient to develop, the species cannot survive whereas B. (Ph.) globosus can do so. This intolerance of high temperature regimes on the part of B. pfeifferi accounts for the species' adoption of a discontinuous distribution over the coastal plain of south-eastern Africa. A comparable pattern has been reported for the species over this plain northwards to approximately 16°S latitude in Mozambique and is probably due to a similar high-temperature effect. Further northwards in equatorial latitudes B. pfeifferi is restricted to the more elevated and cooler areas above an altitude of 500 - 600 m, probably because the very high temperature regimes prevailing in the lowlands there exclude the species altogether.
39

Cargo Insurance Claims and Subrogation in International Law – Comparative Study in Marine and Aviation

Martinez Casielles, José A. 03 1900 (has links)
No description available.
40

Staphylococcus aureus of canine nostril origin : bacteriophage typing, antibiotic sensitivity, and biochemical characteristics of isolated cultures

Garner, Harold Edward January 2011 (has links)
Digitized by Kansas State University Libraries

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