Search
Now showing items 1-20 of 41
Sphingolipid metabolic enzymes modulate anticancer drug resistance
(University of Missouri--Columbia, 2006)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] One of the most challenging aspects of cancer therapy today is the problem of drug resistance. The aim of our research is to understand the molecular ...
Evolution of signal frequency in Neoconocephalus (Orthoptera: Tettigoniidae) : a study of perceptual and environmental sources of selection
(University of Missouri--Columbia, 2007)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Mate-attraction signals offer an ideal opportunity to examine the sources of selection that shape traits and trait diversity, as they are very diverse ...
Differential roles for hedgehog signaling in motor neuron development
(University of Missouri--Columbia, 2006)
Induction of neurons in the correct number and location is essential for the proper development and function of a nervous system. Signaling mediated by the Hedgehog (Hh) family of secreted proteins plays a vital role in ...
Nectar in nicotiana : pollinator associations, sources of variation, and evolutionary consequences
(University of Missouri--Columbia, 2007)
Nectar is the primary floral reward offered by plants to attract pollinators. Pollinators often exhibit a preference for certain types of nectars over others. If pollinator preferences for certain nectar traits are strong ...
Ecological conditions of secondary sexual dimorphism in salix glauca : fundamental and realized dimorphic niche
(University of Missouri--Columbia, 2006)
This thesis explores the dimorphic niche of ecological conditions hypothesis as the selective force behind secondary sexual dimorphism in Salix glauca, a dioecious willow shrub. The dimorphic niche hypothesis predicts trait ...
Mechanisms of call recognition in three sympatric species of Neoconocephalus (Orthoptera: Tettigoniidae) : asymmetrical interactions and evolutionary implications
(University of Missouri--Columbia, 2006)
Scientists have debated the hypothesis of reinforcement. Nevertheless, recent empirical and theoretical work have dispelled doubts about its existence. Reinforcement is most often studied by establishing one of its predicted ...
Conservation and ecology of breeding landbirds in a riparian restoration context
(University of Missouri--Columbia, 2006)
While $14 to $15 billion have been invested in 37,000+ river and stream restoration projects in North America since 1990, only 10% are monitored for biological function. My work examines factors that affect landbird ...
Centromere function and evolution in maize (Zea mays)
(University of Missouri--Columbia, 2006)
A dispensable supernumerary chromosome present in maize, the B chromosome, was the focus of many centromere studies. First, I examine the variation in copy number of centromeric elements and other repeats among different ...
The interploidy hybridization barrier in Zea Mays L.
(University of Missouri--Columbia, 2006)
The failure of endosperm development due to interploidy crosses could be due to two reasons, neither of which has been studied on its own. 1) There is an imbalance of inherited imprinted loci in the endosperm (HAIG and ...
Obesity: a growing concern about fetal nutrition
(University of Missouri--Columbia, 2006)
Obesity is a growing epidemic and a major health concern in the United States and elsewhere. The Fetal Basis of Adult Disease (FBAD) theory holds that events that occur during development can permanently alter gene expression ...
The role of terrrestrial habitat in the population dynamics and conservation of pond-breeding amphibians
(University of Missouri--Columbia, 2007)
I used both demographic modeling and experimental field research to evaluate the role of terrestrial habitat in the population dynamics and conservation of pond-breeding amphibians. I began by using literature data to ...
Quantitative biological studies at cellular and sub-cellular level
(University of Missouri--Columbia, 2007)
We developed a translational magnetic tweezers for quantitative measurements at cellular and sub-cellular level. In the cellular studies, multiple membrane tethers were extracted simultaneously under constant force transduced ...
Beyond the edge : riparian habitat use and forest management effects on stream salamanders in the southern Appalachian mountains
(University of Missouri--Columbia, 2007)
While there are many types of habitat loss and degradation (e.g., agriculture, land development), many studies have focused on the impacts of logging on wildlife populations and on ecosystem processes. Little information, ...
Raptor and wading bird migration in Veracruz, Mexico : spatial and temporal dynamics, flight performance, and monitoring applications
(University of Missouri--Columbia, 2007)
This dissertation is organized in four chapters that deal with different aspects of my long-term studies of migratory raptors, vultures, and wading birds, in central Veracruz, Mexico, during the course of three spring and ...
The effects of axotomy on the biophysical properties of reticulospinal neurons in larval lamprey
(University of Missouri--Columbia, 2006)
Following severe spinal cord injury (SCI), in adult higher vertebrates there is little or no axonal regeneration, and animals remain paralyzed below the lesion. In contrast, lower vertebrates such as the lamprey, following ...
Behavioral choice and demographic consequences of wood frog habitat selection in response to land use
(University of Missouri--Columbia, 2007)
Land use is a pervasive form of disturbance affecting natural systems on Earth. My dissertation research is set within the context of a large scale project referred to as Land-use Effects on Amphibian Populations (LEAP), ...
Noise and signal transmission properties as agents of selection in the vibrational communication environment
(University of Missouri--Columbia, 2007)
Members of the Enchenopa binotata species complex (Hemiptera: Membracidae) are host-specific phytophagous insects that communicate by sending vibrations through their host plants. Successful communication depends on the ...
The biology of the Florida scrub endemic millipede: Floridobolus penneri
(University of Missouri--Columbia, 2006)
Even though millipedes provide a number of important ecosystem services, the group overall is understudied and nowadays largely ignored in the USA. Most millipedes that are well-studied occur in temperate, mesic environments, ...
A multi-scale investigation of ecologically relevant effects of agricultural runoff on amphibians
(University of Missouri--Columbia, 2008)
Modification of landscapes for agricultural production can introduce agrochemicals into surface waters and degrade aquatic habitats used by many amphibians for breeding and larval development. Although many ecotoxicological ...
Identification and characterization of M cells in the mammalian conjunctiva
(University of Missouri--Columbia, 2007)
The M cell is a morphologically and functionally distinct epithelial cell found in the follicle associated epithelium (FAE) above organized lymphoid tissue at distinct locations along mucosal surfaces. By sampling antigens ...