Life Sciences Commons^™

Fish Assemblage Structure In Natural, Channelized, And Restored Sections Of Nippersink Creek, Mchenry County, Illinois, Sarah Ann Zack

Master's Theses

Degradation of aquatic habitats and loss of biodiversity are growing concerns of natural resource managers and the general public. Channelization, the common historical practice of straightening streams and rivers for agricultural interests, has had profound detrimental effects on the biodiversity of lotic fish assemblages. Nippersink Creek, McHenry County, IL is a twenty-three mile stream that flows through an area valued for its fish, wildlife, and invertebrate biodiversity. Although a portion of the stream was channelized in the 1950's, restoration efforts by the McHenry County Conservation District have recently restored historical meanders. Nevertheless, efforts to restore streams and rivers to their …

Temporal Variability Of Bioassessment Indices Used To Evaluate Three Midwestern Streams, Nia M. Haller

Master's Theses

Population, community and functional measures or metrics in rapid bioassessment programs aid in establishing biological criteria for streams and rivers. Each metric measures different aspects of community structure and is important in detecting changes in macroinvertebrate community structure that are influenced by changes in water quality. In this study, temporal variation of nine commonly used bioassessment indices was examined in three midwestern streams. The indices were calculated for each of nine replicate benthic macroinvertebrate samples collected monthly for one year from Cowpie Creek (CC), Nippersink Creek (NC) and Lawrence Creek (LC), McHenry County, Illinois. In practice, the habitat sampled for …

Diet Overlap And Competition Among Native And Non-Native Small-Bodied Fishes In The Colorado River, Grand Canyon, Arizona, Sarah Ellen Zahn Seegert

Master's Theses

Introductions of non-native fishes are threatening native fish communities in streams and rivers across the United States. The Colorado River especially has experienced numerous species invasions, and native fish populations throughout the basin are in decline. The native fish community in the Grand Canyon has been particularly affected, with half of the native fishes extirpated from the canyon. Many scientists blame interactions with non-native fishes for these declines. However, to date no one has conducted a thorough diet analysis of small-bodied fishes in the system to assess overlap between native and non-native fish diets. I analyzed the diets of native …

Resource Composition And Macroinvertebrate Resource Consumption In The Colorado River Below Glen Canyon Dam, Holly Ann Alfreda Wellard Kelly

Master's Theses

Physical and biological changes to rivers induced by large dams can significantly alter downstream communities, decreasing the biotic integrity of these rivers. For example, completion of Glen Canyon Dam on the Colorado River in 1963 has altered the downstream ecosystem and contributed to the decline of native fish populations and dramatic changes in the macroinvertebrate communities. Physical changes associated with the dam may also influence the food resources supporting macroinvertebrate production, but this has not been previously measured. For example, autochthonous production is high in the clear tailwaters of the dam, but downstream tributary allochthonous carbon inputs are substantial and …

Structure-Function Relationship Studies Of The Udp-Glucose Pyrophosphorylase From Escherichia Coli, Agnieszka Maria Orlof

Master's Theses

UDP-Glucose Pyrophosphorylase (UDP-Glc PPase) is a key enzyme of the carbohydrate metabolic pathway widely used among prokaryotes and eukaryotes. In plants, UDP-Glc PPase is necessary for sucrose synthesis while mammals utilize this enzyme for the production of glycogen. A bacterium such as Escherichia coli uses UDP-Glc PPase for biosynthesis of the lipopolysscharide core which forms a cell wall.

This study focused on UDP-Glc PPase from Escherichia coli which is encoded by both galU and galF genes. The first part of this project investigated amino acids that could play an important role in the function of UDP Glc PPase (GalU). Based …

Functional And Phenotypical Analysis Of The Effects Of Aging On B Cells And Their Bone Marrow Microenvironment, Nicole May Ziegler

Master's Theses

Aging impacts multiple organ systems, and specifically causes the immune system to lose its ability to efficiently fight off infections. Regarding immunity, aging research predominantly focuses on the adaptive immune system. B cells, which mediate the humoral arm of the adaptive immune system, develop throughout life in the bone marrow where microenvironmental `niches' are important. The bone marrow does not exactly `atrophy' with age; however, studies comparing young and old mice demonstrate an age-related change in the bone marrow B cell subpopulations.

The overall goal was to determine if femoral and sternum bone marrow have different plasma cell composition and …

The Distribution Of Gnrh And Erbeta In Pre- And Post-Pubertal Male Rats, Maysaa Nageeb

Master's Theses

The hypothalamic-pituitary- gonadal axis is intrinsic in regulating reproductive function. Each part orchestrates the synthesis and release of a key hormone. At the level of the hypothalamus, Gonadotropin- releasing hormone (GnRH) is released and it is the

most upstream regulator of sexual maturation. GnRH neurons express a type of estrogen receptor, ERbeta, which suggests that estradiol (E2) plays a direct role in modulating GnRH function (Herbison and Pape 2001). The objective of this study was to determine if gonadal steroid hormones regulate the expression of ERbeta and GnRH mRNA in the male brain during pubertal development. In-situ hybridization was used …

Phenotypical And Functional Analysis Of Peripheral T Cells In Foxn1 Transgenic Mice: Effects Of Aging, Paulette Krishack

Master's Theses

The thymus is the primary organ for the development and production of TCRαβ naive T cells. However, with increasing age thymic involution occurs, causing a decline in the output of naïve T cells. The decline in naïve T cell production results in a contraction in the peripheral naïve and expansion of the memory T cell pools. Not only are the production and compositions of peripheral T cells altered with age, T cell functions such as T cell proliferation and production of cytokines required for cell proliferation are also declined. Currently, it is not known if restoring the decline in the …

Localization And Functional Analysis Of Plasmodium Falciparum Genes Pfl2550w And Pff0750w, Carolyn Jane Strobel

Master's Theses

Malaria is a parasitic disease that causes over a million deaths worldwide each year. Understanding development through the parasite's life cycle is necessary to stop disease transmission. As the genetic basis for the crucial transition from the erythrocytic asexual cycle to gametocytogenesis is unknown, we hope to better understand this transition by studying sexual stage genes and their roles in gametocytogenesis. PFL2550w and PFF0750w are genes upregulated during gametocytogenesis that were identified by a whole-genome microarray comparing gene expression between gametocyte-producing and gametocyte-deficient strains. In this study, PFL2550w was shown to be a soluble protein that is exported from the …