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Articles 1 - 17 of 17

Full-Text Articles in Life Sciences

Aging, Stem Cells And The Cancer Stem Cell Hypothesis, Dave Comstock Jan 2012

Aging, Stem Cells And The Cancer Stem Cell Hypothesis, Dave Comstock

Dissertations and Theses

No abstract provided.


The Molecular And Genetic Characterization Of L(3)Hem2 And L(3)Hem1, Putative Novel Alleles Of The Neurogenic Gene, Neuralized, Maria A. Otazo Jan 2012

The Molecular And Genetic Characterization Of L(3)Hem2 And L(3)Hem1, Putative Novel Alleles Of The Neurogenic Gene, Neuralized, Maria A. Otazo

Dissertations and Theses

No abstract provided.


Role Of Glia Subsets In Neurodegeneration And Life Span Reduction; Gain-Of-Function Phenotypes Following Glia Specific Overexpression Of Rap/Fzr, An Activator Of The Anaphase-Promoting Complex, Amandeep Kaur Jan 2012

Role Of Glia Subsets In Neurodegeneration And Life Span Reduction; Gain-Of-Function Phenotypes Following Glia Specific Overexpression Of Rap/Fzr, An Activator Of The Anaphase-Promoting Complex, Amandeep Kaur

Dissertations and Theses

No abstract provided.


Φ 6 Polymerase Conformation; Rna Packaging Portal Stability., Elena Futerman Jan 2012

Φ 6 Polymerase Conformation; Rna Packaging Portal Stability., Elena Futerman

Dissertations and Theses

No abstract provided.


Glia-Mediated Neurodegeneration In The Drosophila Melanogaster Cns, Ivan J. Santiago Jan 2012

Glia-Mediated Neurodegeneration In The Drosophila Melanogaster Cns, Ivan J. Santiago

Dissertations and Theses

No abstract provided.


Death- Associated Protein Kinase (Dapk); A Possible Modulator Of Neurodegeneration In A Caenorhabditis Elegans Model Of Excittotoxicity, John Smith Del Rosario Jan 2012

Death- Associated Protein Kinase (Dapk); A Possible Modulator Of Neurodegeneration In A Caenorhabditis Elegans Model Of Excittotoxicity, John Smith Del Rosario

Dissertations and Theses

No abstract provided.


Morphological And Neuroanatomical Changes Associated With The Induction Of Neurodegeneration And Life Span Reduction In Drosophila Melanogaster By Glia Targeted Expression Of Cdh1/Rap/Fzr, An Activator Of The Anaphase Promoting Complex, Israel Nnah Jan 2012

Morphological And Neuroanatomical Changes Associated With The Induction Of Neurodegeneration And Life Span Reduction In Drosophila Melanogaster By Glia Targeted Expression Of Cdh1/Rap/Fzr, An Activator Of The Anaphase Promoting Complex, Israel Nnah

Dissertations and Theses

"The retina aberrant in pattern (rap) gene encodes the Fizzy-related protein (Fzr), an activator of the E3 ubiquitin ligase complex: the Anaphase Promoting Complex/Cyclosome (APC/C). APC/C facilitates the cell cycle stage-specific degradation of cyclins and other mitotic regulators, resulting in the inactivation of Cdk (Cyclin Dependent Kinase) complexes, thus promoting completion of mitosis. Previous studies from our laboratory have shown that Rap/Fzr (the Drosophila homolog of the mammalian Cdh1) regulates glia differentiation and promotes neuron formation. Recent studies have shown that the glia specific over expression of Rap/Fzr causes progressive neurodegeneration and life span reduction preceded by temperature sensitive paralysis, …


Externally-Expressed Fluorescence Across Sexes, Life Stages, And Species Of Spiders, Erin Brandt Jan 2012

Externally-Expressed Fluorescence Across Sexes, Life Stages, And Species Of Spiders, Erin Brandt

Dissertations and Theses

Although all spiders possess fluorophores in their hemolymph, the expression of external fluorescence is much more restricted. The purpose of this study was to evaluate differences in externally-expressed fluorescence between sexes, life stages, and species of spiders. To approach this question, we developed novel instrumentation to capture fluorescence with photographs of our specimens. We paired these fluorescence measurements with spectrometer measurements to attempt to determine the role that fluorescence plays in the overall coloration in spiders. The study was divided into four sections. First, we examined how fluorescence varies in sexes and life stages in Misumena vatia, an ambush predator …


Effects Of Reactive Oxygen Species On Life History Traits Of Caenorhabditis Elegans, Samson William Smith Jan 2012

Effects Of Reactive Oxygen Species On Life History Traits Of Caenorhabditis Elegans, Samson William Smith

Dissertations and Theses

Evolutionary life history theory predicts that tradeoffs among fitness-related phenotypes will occur as a result of resource limitations and/or physiological constraints. Such tradeoffs are defined as the cost(s) incurred on one component of fitness (e.g., reproduction) by the increased expression of another fitness-related trait (e.g., longevity). Only recently have researchers begun to investigate the mechanistic bases of life history tradeoffs. A recent proposal is that reactive oxygen species (ROS) have a central role in shaping life history traits and tradeoffs. Research on disparate animal taxa has highlighted strong correlations between oxidative stress resistance and fitness-related life history traits, for example. …


The Role Of Clay Minerals In The Transformation Of E. Coli, Ekaterini Porttellou Jan 2012

The Role Of Clay Minerals In The Transformation Of E. Coli, Ekaterini Porttellou

Dissertations and Theses

No abstract provided.


Slave Drivers; Increased Foraging By Host Workers Under The Slave-Making Ant Plotomognathus Americanus, Kevin Purce Jan 2012

Slave Drivers; Increased Foraging By Host Workers Under The Slave-Making Ant Plotomognathus Americanus, Kevin Purce

Dissertations and Theses

No abstract provided.


The Effects Of Pleistocene Climatic Change On The Phylogeography Of Euploea Mulciber (Lepidoptera; Nymphalidae; Danainae), Elva Yang Jan 2012

The Effects Of Pleistocene Climatic Change On The Phylogeography Of Euploea Mulciber (Lepidoptera; Nymphalidae; Danainae), Elva Yang

Dissertations and Theses

No abstract provided.


Anatomical Analysis Of The Feedback Projections From Extrastriate Cortex To Area 18 In Ferret Visual Cortex, Moody Saint Louis Jan 2012

Anatomical Analysis Of The Feedback Projections From Extrastriate Cortex To Area 18 In Ferret Visual Cortex, Moody Saint Louis

Dissertations and Theses

The purpose of this thesis is to characterize the cortical inputs to area 18 of ferret visual cerebral cortex. Contrary to feedforward connections, feedback connections are presumed to have a modulatory influence on the responses of lower order neurons providing information already processed. Input from feedback connections can supposedly elicit changes in the response to stimuli within the receptive field and may be involved in the role of discriminating objects relative to the background. The aim of our set of experiments was to fully analyze and compare the anatomical characteristics of feedback connections to area 18 from extrastriate areas as …


Feasibility Study Of Trans-Cranial Direct Current Stimulation In Presence Of Brain Tumor, Abhilash Nair Jan 2012

Feasibility Study Of Trans-Cranial Direct Current Stimulation In Presence Of Brain Tumor, Abhilash Nair

Dissertations and Theses

Trans-cranial Direct Current Stimulation has been shown to modulate cortical neuronal activity. Weak constant current is applied to the scalp using electrodes, leading to sub-threshold changes in neuronal membrane potential. Before actual clinical stimulation is performed, such systems are validated by simulating the stimulation and the resulting current flow patterns using finite element solvers. However, the reliability of such models depends upon the accuracy with which the underlying anatomy has been modeled [1]. In earlier studies it has been shown that the current flow patterns within the brain are altered due to the presence of lesioned brain tissues[2]. Here we …


Use Of Two-Dimensional Agarose-Gel Analysis To Characterize Processing Of Uv-Irradiated Plasmids And The Composition Of The Replisome Following Uv-Induced Arrest, Harout Arthur Jeiranian Jan 2012

Use Of Two-Dimensional Agarose-Gel Analysis To Characterize Processing Of Uv-Irradiated Plasmids And The Composition Of The Replisome Following Uv-Induced Arrest, Harout Arthur Jeiranian

Dissertations and Theses

In this thesis, I address two fundamental questions related to our understanding of how DNA damage is processed and repaired during replication. Using Two-dimensional (2-D) agarose gel analysis, I first examine whether DNA damage on plasmids introduced by transformation is processed in a manner similar to that observed on endogenously replicating plasmids and the chromosome. The original intent for using this approach was to develop a technique that could examine how different DNA adducts would be repaired in various sequence contexts. However, I found that distinct differences exist between the processing of DNA damage on transforming plasmids and the chromosome. …


Causes And Consequences Of Mitochondrial Variation In Caenorhabditid Nematodes, Kiley Ann Hicks Jan 2012

Causes And Consequences Of Mitochondrial Variation In Caenorhabditid Nematodes, Kiley Ann Hicks

Dissertations and Theses

Mitochondria are dynamic organelles that harbor their own stream-lined genome and generate much of the ATP necessary to sustain eukaryotic life via an electron transport chain (ETC). Because of the central role for mitochondria in organismal physiology, mitochondrial genetic and phenotypic variation can alter organismal fitness and affect population genetic and evolutionary outcomes. Despite the far-reaching relevance of mitochondria to evolutionary processes and human health, we lack a basic understanding of the causes and consequences of mitochondrial genetic and phenotypic variation. In this thesis, I quantified mitochondrial reactive oxygen species (ROS), membrane potential (δΨM), and mitochondrial morphological traits within Caenorhabditis …


The Role Of Nucleotide Excision Repair In Restoring Replication Following Uv-Induced Damage In Escherichia Coli, Kelley Nicole Newton Jan 2012

The Role Of Nucleotide Excision Repair In Restoring Replication Following Uv-Induced Damage In Escherichia Coli, Kelley Nicole Newton

Dissertations and Theses

Following low levels of UV exposure, Escherichia coli cells deficient in nucleotide excision repair recover and synthesize DNA at near wild type levels, an observation that formed the basis of the post replication recombination repair model. In this study, we characterized the DNA synthesis that occurs following UV-irradiation in the absence of nucleotide excision repair and show that although this synthesis resumes at near wild type levels, it is coincident with a high degree of cell death. We confirm that the replication occurring under these conditions involves extensive levels of strand exchange. However, cells undergoing this form of replication accumulate …