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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.
61

Electromyograph biofeedback and the treatment of chronic low back pain

Bush, Clarissa. January 1984 (has links)
Sixty-six chronic low back pain sufferers, recruited through the media, were randomly divided into three groups. Following an assessment consisting of psychological questionnaires, pain monitoring and measurement of paraspinal electromyogram (EMG), one group received paraspinal EMG biofeedback, and a second group received a placebo treatment. The third group received no intervention. Two further assessments were carried out on all groups immediately after and three months after treatment. All groups showed significant reductions in pain, anxiety, depression and paraspinal EMG, but there were no differences among the groups. A regression analysis failed to identify subject characteristics which predicted positive outcome in the biofeedback group, but the Evaluative scale of the MPQ and hypnotizability were significant predictors of outcome for the placebo group. The results are discussed in terms of a general placebo effect of participating in research designed to reduce pain. It is concluded that paraspinal EMG biofeedback is not an effective treatment for chronic low back pain in a non-hospitalized population.
62

Field and laboratory trials in Mali to determine the effects of neem extracts on three millet pests, Heliocheilus albipunctella De Joannis (Lepidoptera: Noctuidae), Coniesta ignefusalis Hampson (Lepidoptera: Pyralidae) and Kraussaria angulifera Krauss (Orthoptera: Acrididae)

Passerini, Julien January 1991 (has links)
Formulations of aqueous neem extracts were sprayed in field experiments. Results showed that a 0.5% and 1% concentrations were effective in reducing grasshopper feeding and diminishing damage caused by the millet stemborer, C. ignefusalis. In 1988, neem diminished egg-laying and mine damage by the headminer, H. albipunctella, but no data were available for 1989 because of the low infestation levels of this pest. / Neem exhibited some systemic activity. Soil applied neem kernel powder partially protected millet against K. angulifera and C. ignefusalis. Neem treated plots yielded more grain and suffered less damage by insect pests than four different cultural practices. Only the addition of fertilizer was superior to neem in reducing yield losses but it was inferior in limiting pest losses. / Experiments to test the residual activity of neem showed that this botanical insecticide can effectively protect millet against K. angulifera for at least seven days, and possibly longer if ultra-violet rays and rainfall are not prevalent. Analysis of plant selection behavior of K. angulifera showed that neem is an antifeedant rather than a repellent. On first to third instar nymphs, growth regulating activity expressed as a difficulty in molting or an absence of sclerotization may occur. Topical applications of neem to the stemborer, C. ignefusalis, also caused growth abnormalities, mostly molting disturbances. Treated larvae that reached the adult stage were malformed. / This research indicates that neem based insecticides offer considerable promise for Sahelian farmers for protecting millet crops. It is effective against K. angulifera, but less effective against the stemborer, C. ignefusalis. Although the data obtained for H. albipunctella in 1988 was promising, it was insufficient to reach any conclusions regarding neem's efficacy with respect to this pest.
63

Alternaria alternata f. sp. sphenocleae, a potential mycoherbicide of gooseweed (Sphenoclea zeylanica gaertner) / Alternaria alternata to control gooseweed (Sphenoclea zeylanica)

Masangkay, Rhomela Favila. January 1996 (has links)
A foliar pathogen identified as a member of the genus Alternaria was isolated from blighted Sphenoclea zeylanica (gooseweed) collected in 1991 from a rice field near Los Banos, Laguna, Philippines. Inoculum density, dew period, and plant height are factors influencing biocontrol of S. zeylanica with this indigenous pathogen. Significantly higher percent reductions in plant height and dry weight were obtained and all plants were killed at higher inoculum concentrations with 8 h of dew. The number, germination, and virulence of conidia were significantly affected by production techniques, temperature, light condition, and incubation period. Exposure to continuous near-ultraviolet (NUV) light at 28$ sp circ$C stimulated sporulation on agar media and on solid substrates. Overall, the best production technique was the use of sorghum seeds using an equal quantity of sorghum seeds and water (w/v) incubated for four weeks. Another conidia production method using the sporulation medium (S-medium) technique was evaluated with the addition of 20 g L$ sp{-1}$ of calcium carbonate (CaCO$ sb3)$ and 2 ml of sterile distilled water. Primary 1/2 PDA at 18$ sp circ$C in the dark produced the most virulent conidia. This technique produced conidia relatively rapid, but was labour intensive. Host range studies using 49 plant species in 40 genera representing 20 families, selected by using a modified centrifugal phylogenetic and variety strategy indicated that only S. zeylanica was susceptible in the absence and presence of supplemental dew. On the basis of morphological and cultural characteristics, pathogenicity on the host, host specificity, and the absence of a previous record of this fungal pathogen on S. zeylanica, the binomial A. alternata f. sp. sphenocleae is proposed.
64

Knowledge of response in thermal biofeedback training using false feedback

Haifley, Thomas D. January 1980 (has links)
This thesis has explored the effects of three variables in thermal biofeedback training using false feedback. The three controlled variables in this study are: knowledge of response for the student experimenter, and training sessions. Knowledge of response refers to the identification of a particular internal response (either GSR or skin temperature) of a subject.Although not statistically significant, results for the knowledge of response variables were found to be in the theoretically predicted direction in all conditions.
65

Screening criteria leading to the testing of the effects of Clostridium putrefariens (McBryde) on the European corn borer

Bishop, Michael J. January 1970 (has links)
The use of Clostridium species as possible pathogens of the European corn borer, Ostrinia nubilalis (Hubner) was arrived at by using screening criteria derived from studying the environment of the insect mid-gut and correlating these criteria to known physiological factors of bacteria. European corn borer larvae were treated by placing one drop of bacterial suspension on a corn borer egg mass. The newly-hatched larvae were then transferred to sterile, individual vials with synthetic food medium and observed daily. Clostridium putrefaciens (McBryde) treated larvae showed a significant reduction in hatching, slowed growth rate and a mortality of 50%.
66

Endogenous resistance to insect pests in alfalfa : engineering for enhanced resistance

Mazahery-Laghab, Hojjatollah January 1997 (has links)
Alfalfa (Medicago sativa) is a valuable forage crop grown throughout the World. While the crop is resistant to attack by many insect pests, it is subject to potentially severe losses through the action of several specific pests, which are adapted to alfalfa as a host. The most economically damaging of these pests is the alfalfa weevil, Hypera postica. This thesis investigates the endogenous defences of alfalfa against insects, which are responsible for its resistance to non-pest species, and develops a strategy for increasing the resistance of alfalfa towards pest species, specifically alfalfa weevil. The role of saponins in the resistance of alfalfa towards non-pest species has been investigated by using successive insect bioassays, carried out with extracts, mixtures of compounds, and purified compounds, to identify which compounds present in alfalfa tissues are responsible for toxicity towards insects. Crude saponin extracts, in 80% methanol, from alfalfa seedling tissues were bioassayed against the cowpea seed weevil, Callosobruchus maculatus. Both extracts from shoot and root tissues caused larval mortality and delayed development when incorporated into an artificial diet at levels comparable to those found in alfalfa, but lower levels of root saponin extracts showed probiotic effects, whereas lower levels of shoot saponins were still toxic. Hydrolysis of the saponins present in these extracts decreased their toxicity. Purified saponin mixtures were prepared by butanol partition and ether precipitation, and were bioassayed against potato aphid (Aulacorthum solani) in a liquid artificial diet, which allowed quantitative effects to be accurately assayed. Shoot saponins showed a concentration-dependent toxic effect, decreasing survival over an initial 5 day period, decreasing growth, and inhibiting fecundity (measured by nymph production) in these insects. Alfalfa root saponins showed no deleterious effects below a threshold level, but caused complete mortality above this level. The alfalfa saponin mixtures were separated into fractions by chromatography on a reverse phase column. Bioassays showed that the toxicity towards potato was associated only with fractions containing saponins, and that fractions containing a component identified as soyasaponin I were more toxic to the aphids than others. Finally, two saponins purified from alfalfa, soyasaponin I and medicoside A, were assayed. These assays showed that soyasaponin was consistently more toxic in effects on mortality, growth and fecundity. It was concluded that alfalfa saponins, and in particular soyasaponin I, were major factors in the resistance of alfalfa towards potato aphid, and other insects. A saponin mixture from another species, sugar beet {Beta vulgaris) was also toxic to aphids, supporting the view that saponins have a general role in resistance to insects. Inhibition of insect digestive proteolysis by expression of a foreign protein protease inhibitor was selected as a strategy to protect transgenic alfalfa against alfalfa weevil. The major protease activity in larvae of this msect was shown to be due to cysteine proteases, which could be inhibited by cystatins. Rice cystatin was produced in large quantity using a recombinant protein expression system in E. coli for use in a "proving" experiment. Incorporation of the rice cystatin into an alfalfa weevil larvae artificial diet decreased survival, showing that this approach was feasible.
67

Control of Dermestes maculatus (Coleoptera:Dermestidae) in an interior storage situation with neem, Azadirachta indica

Keeler, Cory M. January 1999 (has links)
Neem, Azadirachta indica, products were tested for toxic, growth regulating, primary antifeedant, and secondary antifeedant effects on Dermestes maculatus, under conditions approximating those found in storage facilities. Toxic and growth regulating effects were investigated using topical application of mineral oil, neem oil, purified azadirachtin/methanol solution, and 10% neem seed kernel extract/methanol solution. All neem treatments exhibited higher mortality than the mineral oil treatment 5, 10, and 14 days after the application of the treatments; larvae treated with neem products often failed to pupate and never emerged as adults. Primary antifeedant effects of azadirachtin (1.5 g/L and 5 g/L) were investigated with an original no-choice feeding bioassay. Significant primary antifeedant effects were observed which were persistent for up to 13 weeks for adults and 17 weeks for larvae. Significant secondary antifeedant effects were also demonstrated after topical application of azadirachtin (.125 g/L, .25 g/L and .5 g/L) to the larvae.
68

Modeling, identification and control of a dynamic and stochastic chemical biological process

Adeyemi, Suleyman Olatunji, January 1976 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1976. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 358-372).
69

A pheromone-mediated mass-trapping program for three species of ambrosia beetle in a commercial sawmill

Shore, Terence Leckie January 1982 (has links)
A commercial sawmill in British Columbia, Canada, was surveyed in 1979 for the presence of the ambrosia beetles Trypodendron lineatum (Olivier) and Gnathotrichus retusus (LeConte) using pheromone-baited traps. The temporal and spatial distribution and relative abundance of these species were determined. This information was used during 1980 and 1981 to develop a mass-trapping program for these species while maintaining the integrity of an existing trapping program for a third ambrosia beetle species, G. sulcatus (LeConte). A fourth ambrosia beetle species, Platypus wilsoni (Swaine) responded in significantly larger numbers to traps baited with the pheromone sulcatol plus ethanol and α-pinene than to those baited with the pheromone lineatin or unbaited. Several experiments were conducted in order to improve or assess the trapping system. It was found that both G. retusus and T. lineatum response to their respective pheromones was increased by the inclusion of ethanol and α-pinene on the traps. T. lineatum response to lineatin was significantly reduced when sulcatol was included in the bait. An experiment conducted to determine optimum trap height showed that largest numbers of T. lineatum were caught on the lowest traps that cleared surrounding understory vegetation. A mark-recapture technique was tested as a potential means of assessing trapping efficiency. Recommendations were made that could result in this technique becoming a useful means of optimizing and evaluating ambrosia beetle mass-trapping programs. This concurrent mass-trapping program for three species of ambrosia beetles demonstrated that large numbers of beetles can be captured using pheromone-baited traps. The relatively low cost of this pest management tactic compared with the high values at risk has already resulted in much of the technology developed in this thesis being incorporated in ambrosia beetle management programs by forest industries in British Columbia. / Forestry, Faculty of / Graduate
70

Alternaria alternata f. sp. sphenocleae, a potential mycoherbicide of gooseweed (Sphenoclea zeylanica gaertner)

Masangkay, Rhomela Favila. January 1996 (has links)
No description available.

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