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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

Applications of Zinc Oxide Nanotip Prepared by Aqueous Solution Deposition on Photonic Devices

Chien, Yu-kai 25 July 2012 (has links)
In this study, we prepare the zinc oxide nanotip with aqueous solution deposited on ZnO nucleation layer. The thermal annealing with N2 ambiance at 300 oC for 1 hr increase the UV emission and decrease the defects. We use ZnO nanotip as an anti-reflection layer because of surface roughness and optical interference. ZnO nanotip with rough surface decreases reflection, so we use ZnO nanotip as an anti-reflection layer, after grown ZnO nanotip on solar cell the efficiency of solar cell was enhancement. The coordination modes were measured by Fourier-transform infrared spectrometer (FTIR). The physical properties were characterized by X-ray diffraction (XRD). The optical properties were measured by Micro-photoluminescence (Micro-PL). The morphology was observed by field emission scanning electron microscope (FE-SEM). The performance of the cells was measured by a semiconductor device analyzer. In our results, we grow the high performance of ZnO nanotip on solar cell to increase the efficiency. The short-circuit current increased from 42 to 51 mA, and the efficiency increased from 15.7 to 18.8 %.
102

The effect of selected forest defoliators on mortality rates and crown conditions in hardwood stands on the Allegheny National Forest

Morin, Randall S. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains vii, 109 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 44-50).
103

An Examination of the Effects and Possible Targets of Nitric Oxide on Olfactory Neurons in the Moth, Manduca Sexta

Wilson, Caroline Hamilton January 2005 (has links)
The gaseous messenger, nitric oxide (NO), has emerged as a key component of olfactory systems. Localization and imaging studies in the moth, Manduca sexta, suggest that NO may affect the excitability of olfactory neurons by modifying neuronal membrane properties through sGC-dependent mechanisms. This hypothesis was tested using a multidisciplinary approach, including two types of physiological recording techniques and immunocytochemical analysis of sGC antibody expression in the Manduca brain. The excitability of large populations or individual antennal lobe (AL) neurons was monitored with in vivo physiological recordings while various NO pharmacological agents were bath applied to the brain. To examine possible targets of NO, the binding site of sGC was blocked and the results were compared to NO blockade. Finally, sGC immunocytochemistry was used to also determine possible targets of NO.Two NO synthesis inhibitors and a sGC blocker were potent effectors of resting, baseline activity in the Manduca brain. Blocking NO synthesis caused significant decreases in AL neuron conductance. This conductance decrease led to changes in baseline activity, including the appearance of bursts in some neurons, and increased and decreased firing rates in other neurons. Further, the neurons had a decreased responsiveness and excitability to presynaptic input. Blocking the sGC binding site caused similar effects in most neurons, which indicates that NO likely acts through sGC-dependent signaling to exert its effects in at least a subset of neurons. However, some neurons had different responses to NO and sGC blockade, which indicates that NO may act through other signaling mechanisms in some neurons. Further examination using sGC immunocytochemistry revealed that only about 90% of projection neurons (PNs) and 30% of local neurons (LNs) contained sGC immunoreactivity.The results in this dissertation indicate that NO performs a global function in the antennal lobe to maintain the resting membrane conductance of AL neurons. NO likely exerts its effects through both sGC-dependent and sGC-independent mechanisms. Finally, these results have major implications for odor coding in all species, as NO has been found in the olfactory systems of every animal examined thus far.
104

Patch exploitation by the parasitoids of Plutella xylostella (L.): from individual behaviour to population dynamics /

Wang, Xin-geng. January 2001 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Applied and Molecular Ecology, 2001. / Includes bibliographical references (leaves 204-230).
105

Phenology, natural enemies, and management of Lepidopteran pests of cole crops in Alabama

Maxwell, Elly Marie, Fadamiro, Henry Y. January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.93-105).
106

Host selection behavior of the Douglas-fir pitch moth, Synanthedon novaroensis (Hy. Edwards) (Lepidoptera:Sesiidae), related to intermediate silvicultural activities /

Johnson, Jay Michael. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographic references (leaves [53]-56).
107

The sublethal effects of methoxyfenozide on the field orientation and courtship behavior of Cydia pomonella (Linnaeus) (Lepidoptera: tortricidae)

Franklin, Amanda Kay. Barrett, Bruce A. January 2008 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on September 22, 2009). Thesis advisor: Dr. Bruce Barrett. Includes bibliographical references.
108

The relationships between snags and cavity-nesting birds in a gypsy moth impacted forest

Showalter, Christopher Ryan. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains vii, 59 p. : ill. (some col.), maps. Vita. Includes abstract. Includes bibliographical references (p. 23-28).
109

Isolation and characterization of highly repetitive fraction of codling moth, \kur{Cydia pomonella} / Isolation and characterization of highly repetitive fraction of codling moth, \kur{Cydia pomonella}

VĚCHTOVÁ, Pavlína January 2011 (has links)
Repetitive DNA comprises substantial part of the eukaryotic genome. ?Junk DNA?, as it was originally understood at the beginning of its discovery has attracted a lot of attention lately due to many studies proving its functional perspectives. Analysis of its dynamics, characteristics and distribution has been widely studied in organisms with monocentric chromosomes. Holokinetic system, however, was left behind in these efforts and whole image of repetitive DNA distribution and dynamics in this system remains to be elucidated. In this thesis various approaches were used to isolate and characterise repetitive DNA in the genome of the codling moth, Cydia pomonella. Satellite DNA CPSAT-1 was successfully isolated, characterised with Dot blot and Southern blot and mapped with FISH in the genome of C. pomonella. 17 microsatellite probes were used to localize microsatellite arrays in the genome of C. pomonella. Method of microsatellite FISH revealed distribution of all tested microsatellites in C. pomonella complement.
110

Genetic variation in wild Imbrasia belina (mopane moths, worms and pupae) populations

Greyling, Monique 06 December 2011 (has links)
M.Sc. / Imbrasia belina is a well-utilised natural resource in southern Africa. This resource can only be utilised sustainably after a thorough study of its ecology, breeding system and its genetic structures are assessed. The implementing of breeding programmes should be evaluated with well-defined management and conservation controls and regulations. The purpose of this study was to establish the amount of genetic variation and gene flow in two wild populations and the staggered generations of I. be/ina, and to determine which developmental stage should be used for further studies. Gene products of 41 protein-coding loci were analysed by horizontal starch gel electrophoresis. High levels of polymorphism (42% and 47%) and heterozygosity (0.182 to 0.21 0) were present in all groups. Results from initial studies indicated developmental constraints on the expression of several loci, namely CK, GPO and PEP-S. After further studies with larger sample sizes, it now appears that there are only allozyme and not isozyme differences between the individuals from the various developmental stages. The groups studied exhibit a large amount of variation within, but little differentiation and a large amount of gene flow between them. Results of the study indicate that the genetic diversity of I. be/ina populations is healthy. Thus, sustainable utilisation of the Messina Experimental farm (November/December) group is recommended due to the high heterozygosity and genetic variation in this population.

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