Thesis (Ph. D.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1928. / Typescript. With this is bound: Purple blotch of onion (Macrosporium porri Ell.), [by] H.R. Angell, reprinted from Journal of Agricultural research, v. 38, no. 9 (May 1, 1929), p. 467-487. Includes bibliographical references ([4] leaves after numbered leaves).

Electron transport in purple bacteria was studied using combination of absorption spectroscopy and induced bacteriochlorophyll fluorescence in whole cells in vivo. Focus is placed on relations between fluorescence yield, the state of the electron transport chain and the membrane potential. A laboratory-built absorption spectrophotometer-fluorimeter is described.

Theory predicts that, upon release from natural enemies in the new range, invasive species will evolve to allocate more resources towards traits that improve their ability to compete with native species. The motivation for most biological control programs is to re-introduce native enemies in order to oppose this effect and reduce or even reverse some of the negative impacts of invasive species on native and economically important ecosystems. In many cases, multiple biocontrol agents are introduced, often under the assumption that their impacts will be complementary. However, studies that attempt to quantify the nature of interactions among biocontrol agents tend to find unique outcomes: as yet, no general patterns have emerged. Here I describe the findings of a study of the impacts of the introduction of one species of biocontrol agent of invasive purple loosestrife, the leaf beetle Neogalerucella almariensis, on the reproductive success of a second biocontrol agent, the flower-feeding weevil Nanophyes marmoratus. Somewhat surprisingly, I found that more adult weevils tended to emerge from plants that were simultaneously infested with both types of beetles. This was true even when differences in flower number among plants were taken into account. Moreover, there were more aborted flowers on an inflorescence where both biocontrol agents were present. Finally, more pollinators visited the plants that were infested by both biocontrol agents. The observational data also show a positive correlation between the presence of the leaf beetle larvae and the number of adult flower weevils found on an inflorescence. I discuss various explanations, including the possibility that biocontrol-induced changes in flowering phenology and plant nutritional compounds could be, at least partially, responsible for these findings.

Master of Science / Department of Human Nutrition / Weiqun Wang / Anthocyanins may prevent chronic diseases such as cancer and cardiovascular disease, however, the anthocyanin metabolites are not well elucidated. We previously selected a purple-fleshed sweet potato clone P40 that contained anthocyanins at up to 7.5 g/kg dry matter, most of which are cyanidin and peonidin derivatives. The main objective of this study is to identify anthocyanin metabolites in the mice fed 20-30% of purple sweet potato P40 (287 mg and 430 mg peonidin-3-glucoside equivalent /kg body weight) diet for 6 weeks. Plasma, liver, and feces were analyzed for anthocyanin metabolites using HPLC/MS and MALDI-TOF-MS. Fifteen hours after consumption of P40 diet, we identified 4 anthocyanin metabolites cyanidin 3,5- diglucoside; cyanidin 3-sophoroside-5-glucoside; cyanidin3-p-hydroxybenzoylsophroside-5-glucoside; and peonidin 3-p-hydroxybenzoylsophroside-5-glucoside in fecal samples. No anthocyanin metabolites were detected in plasma or liver extracts by HPLC/MS or MALDI-TOF-MS. The results indicate that anthocyanin metabolites in fecal samples might provide health benefits for colonic mucosal cells. However, the lack metabolites in both plasma and liver samples suggest a continuous intake of the anthocyanins may be required for systemic benefits due to their quick degradation and low bioavailability.

<p>Ever since it was published in 1982, Alice Walker’s The Color Purple has been celebrated for giving African-American women a voice and for challenging patriarchal structures in society, but it has also been criticised for being stereo-typical in its portrayal of African-American men and women. In this essay I claim that the novel in fact supports patriarchal American society. I discuss this by first looking at the parts of the novel that can be seen as challenging towards patriarchal structures, moving on to a more critical standpoint showing that the resistance towards patriarchal structures in the novel is not at all as strong as it may seem at first.</p>

In the first part of this study we monitored the development of biological control of purple loosestrife Lythrum salicaria over a six-year period at Morgan Lake in western Oregon. In 1992, two beetles, Galerucella pusilla and G. calmariensis (Coleoptera: Chrysomelidae), were released to control the wetland weed at this test site. Our purpose was to estimate quantitative performance parameters that might be generally applied in monitoring biological weed control. Our six performance measures were: 1) biological control agent establishment, 2) the rate of increase of the agents, 3) the rate of spread of the agents, 4) the effect of the agents on individual target plants, 5) the effect of the agents on the population of the target plants, and 6) the indirect impact of the biological control agents on the local plant community. The beetles established viable populations that increased during the study with an intrinsic rate of increase (r), based on the growth rate in damage, estimated at 2.24/year. Within six years after introduction, the beetles spread to saturate the entire purple loosestrife habitat (4100 m��) around the lake. The rate of spread, estimated by calculating a diffusion coefficient (D), was 57.5 m��/year. Adult beetles made seasonal, exploratory movements up to 30 m away from the host plant stand into surrounding crop fields, which suggests a disturbance-free buffer should be established in the habitat surrounding the loosestrife stand. By 1997, both flowering success and median stem density (per 0.125 m�� plot) of purple loosestrife declined to zero. Mean above-ground biomass decreased to 8.4% of its 1994 level. Biomass of native plant species increased by only 3% between 1996 and 1997. Overall, G. pusilla and G. calmariensis reduced the abundance of the target plant at our site. Our monitoring methods were effective at quantitatively measuring the establishment, increase, spread, and damage of the biological control agent, the subsequent decline of the target plant, and the impact on the local plant community. The second part of our study used field and greenhouse experiments to assess non-target effects of two introduced biological control organisms (Galerucella pusilla Duftschmid and G. calmariensis L.: Chrysomelidae) on the economically important ornamental plant, crape myrtle (Lagerstroemia indica L: Lythraceae). Prior host specificity tests performed in the laboratory found that beetles fed, but were unable to complete their life cycle, on this non-target plant. However, there was concern over damage that might occur when the two plant species existed together. This study extended prior tests into a field environment in order to compare the physiological host range revealed in greenhouse tests with the ecological host range revealed in the field. We assumed, based on prior evidence, that the control agents would not complete development on the non-target plant, and therefore, when the non-target organism was isolated from populations of the target organism the direct effects of the biological control agents would be negligible. When the target and non-target organisms existed together, the magnitude of indirect effect of the target organism on the non-target organism via the control agent was expected to increase with: 1) decreasing distance between the target and non-target organisms, and 2) increasing dispersal capability of the control agents. As expected from prior studies beetle feeding and oviposition occurred on crape myrtle but the beetles could not complete development on this non-target plant in our greenhouse and field tests. Leaf damage inflicted by the beetle was lower on crape myrtle than on purple loosestrife plants used as controls and extensive defoliation to the non-target plant was limited to within 30 m from the edge of the purple loosestrife stand. Biomass of crape myrtle was significantly reduced near the stand compared with plants that remained relatively untouched at greater distances. Purple loosestrife biomass exhibited a greater reduction with decreasing distance from the source of beetle colonization. In this thesis we construct and implement strategies for quantitatively assessing success of biological control programs and risk of introduced biological agents to non-target organisms. Through these observations and experiments we hope to increase the predictability and safety of biological control programs. / Graduation date: 1998

Ever since it was published in 1982, Alice Walker’s The Color Purple has been celebrated for giving African-American women a voice and for challenging patriarchal structures in society, but it has also been criticised for being stereo-typical in its portrayal of African-American men and women. In this essay I claim that the novel in fact supports patriarchal American society. I discuss this by first looking at the parts of the novel that can be seen as challenging towards patriarchal structures, moving on to a more critical standpoint showing that the resistance towards patriarchal structures in the novel is not at all as strong as it may seem at first.

Two European leaf-eating beetles, Galerucella calmariensis L. and G. pusilla (Duft.)(Chrysomelidae:Coleoptera) were released at four sites in Quebec to manage the semi-aquatic exotic weed, purple loosestrife (Lythrum salicaria L.). Protocols for monitoring the Galerucella populations and detecting changes in the plant communities were implemented. In addition, the effect of seeding with native plants species in conjunction with Galerucella herbivory was tested in an experiment at a purple loosestrife stand in Ontario. Releases of lab-reared beetles in Quebec in 1996 did not survive to 1997 at any of the 4 sites, but releases of field collected beetles in 1997 overwintered successfully at 3 of the 4 sites. The density of purple loosestrife in 1998 ranged from 28% (Cap Tourmente) to 84% (Hull). The density of Galerucella in 1998 ranged from 6 (Lac St Francois) to 50 (Hull) adults/m 2/min. In the Ontario experiment, herbivory and seeding together interacted to increase the biomass of other plant species significantly---and thereby reduced the dominance (proportion of the biomass) of purple loosestrife---but did not have a significant effect on the biomass of purple loosestrife in the first season.

Acid phosphatases (APases; E.C. 3.1.3.2) catalyze the hydrolysis of phosphate (Pi) from Pi monoesters and anhydrides within the acidic pH range. Induction of intracellular and secreted purple acid phosphatases (PAPs) is a widespread plant response to nutritional Pi-deficiency. The probable function of intracellular APases is to recycle Pi from expendable intracellular organophosphate pools, whereas secreted APases likely scavenge Pi from the organically bound Pi that is prevalent in most soils. Although the catalytic function and regulation of plant PAPs have been described, their physiological function in plants has not been fully established. Recent biochemical and proteomic studies indicated that AtPAP26 is the predominant intracellular (vacuolar) and a major secreted purple APase isozyme upregulated by Pi-starved (-Pi) Arabidopsis thaliana. The in planta function of AtPAP26 was assessed by molecular, biochemical, and phenotypic characterization of a homozygous Salk T-DNA insertion mutant. Loss of AtPAP26 expression resulted in the elimination of AtPAP26 transcripts and 55-kDa immunoreactive AtPAP26 polypeptides, correlated with a 9- and 5-fold decrease in extractable shoot and root APase activity, respectively, as well as a 40% reduction in secreted APase activity of –Pi seedlings. The results corroborate previous findings implying that AtPAP26 is: (i) the principal contributor to Pi starvation inducible APase activity in Arabidopsis, and (ii) controlled post-transcriptionally mainly at the level of protein accumulation. Total shoot free Pi level was about 40% lower in –Pi atpap26 mutants relative to wild-type controls, but unaffected under Pi-sufficient conditions. Moreover, shoot, root, inflorescence, and silique development of the atpap26 mutant was impaired during Pi deprivation, but unaffected under Pi-replete conditions, or during nitrogen or potassium-limited growth, or oxidative stress. The results suggest that the hydrolysis of Pi from organic-phosphate esters by AtPAP26 makes an important contribution to Pi-recycling and scavenging in –Pi Arabidopsis. / Thesis (Master, Biology) -- Queen's University, 2009-09-01 09:46:39.302