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Articles 31141 - 31170 of 39369

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In Situ Muscle Power Differs Without Varying In Vitro Mechanical Properties In Two Insect Leg Muscles Innervated By The Same Motor Neuron, Anna N. Ahn, Kenneth Meijer, Robert J. Full Sep 2006

In Situ Muscle Power Differs Without Varying In Vitro Mechanical Properties In Two Insect Leg Muscles Innervated By The Same Motor Neuron, Anna N. Ahn, Kenneth Meijer, Robert J. Full

All HMC Faculty Publications and Research

The mechanical behavior of muscle during locomotion is often predicted by its anatomy, kinematics, activation pattern and contractile properties. The neuromuscular design of the cockroach leg provides a model system to examine these assumptions, because a single motor neuron innervates two extensor muscles operating at a single joint. Comparisons of the in situ measurements under in vivo running conditions of muscle 178 to a previously examined muscle (179) demonstrate that the same inputs (e.g. neural signal and kinematics) can result in different mechanical outputs. The same neural signal and kinematics, as determined during running, can result in different mechanical functions, …

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Diversity Of The Ig Repertoire Is Maintained With Age In Spite Of Reduced Germinal Centre Cells In Human Tonsil Lymphoid Tissue, G. R. Kolar, D. Mehta, P. C. Wilson, J. D. Capra Sep 2006

Diversity Of The Ig Repertoire Is Maintained With Age In Spite Of Reduced Germinal Centre Cells In Human Tonsil Lymphoid Tissue, G. R. Kolar, D. Mehta, P. C. Wilson, J. D. Capra

Biological Sciences Faculty Research & Creative Works

Humans and almost all species studied to date exhibit a decreased responsiveness to immunization and increased autoimmunity with age. While this has been observed clinically for decades, only recently has an understanding of the molecular basis for these changes begun to be appreciated. Studies of the B-cell aspects of these changes in ageing mice and the very few reports in ageing humans have not been conclusive. Here we examine the nucleotide sequence of over 1250 VH transcripts from the tonsils of individuals of various ages for changes to the VH4 immunoglobulin repertoire. An exhaustive examination of VH, DH and JH …

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Microbial Growth And Biofilm Formation In Geologic Media Is Detected With Complex Conductivity Measurements, Caroline A. Davis, Estella A. Atekwana, Eliot A. Atekwana, Lee D. Slater, Silvia Rossbach, Melanie R. Mormile Sep 2006

Microbial Growth And Biofilm Formation In Geologic Media Is Detected With Complex Conductivity Measurements, Caroline A. Davis, Estella A. Atekwana, Eliot A. Atekwana, Lee D. Slater, Silvia Rossbach, Melanie R. Mormile

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Complex conductivity measurements (0.1-1000 Hz) were obtained from biostimulated sand-packed columns to investigate the effect of microbial growth and biofilm formation on the electrical properties of porous media. Microbial growth was verified by direct microbial counts, pH measurements, and environmental scanning electron microscope imaging. Peaks in imaginary (interfacial) conductivity in the biostimulated columns were coincident with peaks in the microbial cell concentrations extracted from sands. However, the real conductivity component showed no discernible relationship to microbial cell concentration. We suggest that the observed dynamic changes in the imaginary conductivity (σ″) arise from the growth and attachment of microbial cells and …

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Broad Specificity Of Mammalian Adenylyl Cyclase For Interaction With 2',3'-Substituted Purine- And Pyrimidine Nucleotide Inhibitors, Tung-Chung Mou, Andreas Gille, Srividya Suryanarayana, Mark Richter, Roland Seifert, Stephen R. Sprang Sep 2006

Broad Specificity Of Mammalian Adenylyl Cyclase For Interaction With 2',3'-Substituted Purine- And Pyrimidine Nucleotide Inhibitors, Tung-Chung Mou, Andreas Gille, Srividya Suryanarayana, Mark Richter, Roland Seifert, Stephen R. Sprang

Biological Sciences Faculty Publications

Membrane adenylyl cyclases (mACs) play an important role in signal transduction and are therefore potential drug targets. Earlier, we identified 2',3'-O-(N-methylanthraniloyl) (MANT)-substituted purine nucleotides as a novel class of highly potent competitive mAC inhibitors (Ki values in the 10 nM range). MANT nucleotides discriminate among various mAC isoforms through differential interactions with a binding pocket localized at the interface between the C1 and C2 domains of mAC. In this study, we examine the structure/activity relationships for 2',3'-substituted nucleotides and compare the crystal structures of mAC catalytic domains (VC1:IIC2) bound to MANT-GTP, MANT-ATP, and 2',3'-(2,4,6-trinitrophenyl) (TNP)-ATP. TNP-substituted purine and pyrimidine nucleotides …

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Behavioural Responses Of Blue Petrel Chicks (Halobaena Caerulea) To Food-Related And Novel Odours In A Simple Wind Tunnel, Gregory B. Cunningham, Richard W. Van Buskirk, Mark J. Hodges, Henri Weimerskirch, Gabrielle A. Nevitt Sep 2006

Behavioural Responses Of Blue Petrel Chicks (Halobaena Caerulea) To Food-Related And Novel Odours In A Simple Wind Tunnel, Gregory B. Cunningham, Richard W. Van Buskirk, Mark J. Hodges, Henri Weimerskirch, Gabrielle A. Nevitt

Biology Faculty/Staff Publications

No abstract provided.

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Utilization Of Sea Scallop (Placopecten Magellanicus Gmelin) Microsatellite Markers For Phylogenetic Applications In Bay Scallops (Argopecten Irradians Lamarck), Lilliana E.J. Kim, James J. Campanella, Paul Ax Bologna Sep 2006

Utilization Of Sea Scallop (Placopecten Magellanicus Gmelin) Microsatellite Markers For Phylogenetic Applications In Bay Scallops (Argopecten Irradians Lamarck), Lilliana E.J. Kim, James J. Campanella, Paul Ax Bologna

Department of Biology Faculty Scholarship and Creative Works

In previous research, microsatellite markers have been used to geographically and phylogenetically characterize and identify populations of sea scallops (Placopecten magellanicus Gmelin). Given that sea scallops are a closely related species to bay scallops (Argopecten irradians Lamarck), we have investigated whether the flanking DNA sequences of sea scallop microsatellite loci have been conserved in the bay scallop. We found that in all seven sets of published sea scallop PCR primers (Pma130, -132, -135, -180, -200, -212, and -275) that were tested with bay scallop DNA, there was sequence conservation and amplification of microsatellite regions. Our initial phylogenetic analyses, …

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Characterization Of Mmp37p, A Saccharomyces Cerevisiae Mitochondrial Matrix Protein With A Role In Mitochondrial Protein Import, Michelle R. Gallas, Mary Kathryn Dienhart, Rosemary A. Stuart, Roy M. Long Sep 2006

Characterization Of Mmp37p, A Saccharomyces Cerevisiae Mitochondrial Matrix Protein With A Role In Mitochondrial Protein Import, Michelle R. Gallas, Mary Kathryn Dienhart, Rosemary A. Stuart, Roy M. Long

Biological Sciences Faculty Research and Publications

Many mitochondrial proteins are encoded by nuclear genes and after translation in the cytoplasm are imported via translocases in the outer and inner membranes, the TOM and TIM complexes, respectively. Here, we report the characterization of the mitochondrial protein, Mmp37p (YGR046w) and demonstrate its involvement in the process of protein import into mitochondria. Haploid cells deleted of MMP37 are viable but display a temperature-sensitive growth phenotype and are inviable in the absence of mitochondrial DNA. Mmp37p is located in the mitochondrial matrix where it is peripherally associated with the inner membrane. We show that Mmp37p has a role in the …

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Censusing And Measuring Lianas: A Quantitative Comparison Of The Common Methods, Stefan A. Schnitzer, Saara J. Dewalt, Jérôme Chave Sep 2006

Censusing And Measuring Lianas: A Quantitative Comparison Of The Common Methods, Stefan A. Schnitzer, Saara J. Dewalt, Jérôme Chave

Biological Sciences Faculty Research and Publications

Lianas contribute to many aspects of tropical forest diversity and dynamics, and interest in liana ecology has grown substantially in recent years. Methods to census lianas and estimate biomass, however, differ among studies, possibly hindering attempts to compare liana communities. At Nouragues Research Station (French Guiana), we tested the extent to which liana abundance, basal area, and estimated biomass differed depending on stem diameter measurement location, inclusion of ramets, inclusion of lianas rooted within versus passing through the plot, and plot shape. We found that the mean per plot abundance and basal area of lianas were significantly greater when lianas …

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Expression Of The Primary Carbohydrate Component Of The Bordetella Bronchiseptica Biofilm Matrix Is Dependent On Growth Phase But Independent Of Bvg Regulation, Yasuhiko Irie, Andrew Preston, Ming H. Yuk Sep 2006

Expression Of The Primary Carbohydrate Component Of The Bordetella Bronchiseptica Biofilm Matrix Is Dependent On Growth Phase But Independent Of Bvg Regulation, Yasuhiko Irie, Andrew Preston, Ming H. Yuk

Biology Faculty Publications

We previously showed that the Bvg virulence control system regulates biofilm formation in Bordetella bronchiseptica (Y. Irie, S. Mattoo, and M. H. Yuk, J. Bacteriol. 186:5692-5698, 2004). Analyses of the extracellular components of B. bronchiseptica biofilm matrix revealed that the major sugar component in the matrix was xylose, and linkage analysis indicated a majority of it to be in a 4-linked polymeric form. The production of xylose was independent of Bvg regulation but instead was dependent on bacterial growth phase. In addition, N-acetyl-glucosamine in the matrix was found to be important for the initial development of the biofilm. These …

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Secondary Metabolic Gene Cluster Silencing In Aspergillus Nidulans, J. W. Bok, D. Noordermeer, Shubha Kale Ireland, N. P. Keller Sep 2006

Secondary Metabolic Gene Cluster Silencing In Aspergillus Nidulans, J. W. Bok, D. Noordermeer, Shubha Kale Ireland, N. P. Keller

Faculty and Staff Publications

In contrast to most primary metabolism genes, the genes involved in secondary metabolism and certain nutrient utilization pathways are clustered in fungi. Recently a nuclear protein, LaeA, was found to be required for the transcription of several secondary metabolite gene clusters in Aspergillus nidulans. Here we show that LaeA regulation does not extend to nutrient utilization or the spoC1 sporulation clusters. One of the secondary metabolite clusters regulated by LaeA contains the positive regulatory (i.e. aflR) and biosynthetic genes required for biosynthesis of sterigmatocystin (ST), a carcinogenic toxin. Analysis of ST gene cluster expression indicates LaeA regulation of the cluster …

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Macronuclear Genome Sequence Of The Ciliate Tetrahymena Thermophila, A Model Eukaryote, Jonathan A. Eisen, Robert S. Coyne, Martin Wu, Dongying Wu, Mathangi Thiagarajan, Jennifer R. Wortman, Jonathan H. Badger, Qinghu Ren, Paolo Amedeo, Kristie M. Jones, Luke J. Tallon, Arthur L. Delcher, Steven L. Salzberg, Joana C. Silva, Brian J. Haas, William H. Majoros, Maryam Farzad, Jane M. Carlton, Roger K. Smith, Jyoti Garg, Ronald E. Pearlman, Kathleen M. Karrer, Lei Sun, Gerard Manning, Nels C. Elde, Aaron P. Turkewitz, David J. Asai, David E. Wilkes, Yufeng Wang, Hong Cai, Kathleen Collins, B. Andrew Stewart, Suzanne R. Lee, Katarzyna Wilamowska, Zasha Weinberg, Walter L. Ruzzo, Dorota Wloga, Jacek Gaertig, Joseph Frankel, Che-Chia Tsao, Martin A. Gorovsky, Patrick J. Keeling, Ross F. Waller, Nicola J. Patron, J. Michael Cherry, Nicholas A. Stover, Cynthia J. Krieger, Christina Del Toro, Hilary F. Ryder, Sondra C. Williamson, Rebecca A. Barbeau, Eileen P. Hamilton, Eduardo Orias Sep 2006

Macronuclear Genome Sequence Of The Ciliate Tetrahymena Thermophila, A Model Eukaryote, Jonathan A. Eisen, Robert S. Coyne, Martin Wu, Dongying Wu, Mathangi Thiagarajan, Jennifer R. Wortman, Jonathan H. Badger, Qinghu Ren, Paolo Amedeo, Kristie M. Jones, Luke J. Tallon, Arthur L. Delcher, Steven L. Salzberg, Joana C. Silva, Brian J. Haas, William H. Majoros, Maryam Farzad, Jane M. Carlton, Roger K. Smith, Jyoti Garg, Ronald E. Pearlman, Kathleen M. Karrer, Lei Sun, Gerard Manning, Nels C. Elde, Aaron P. Turkewitz, David J. Asai, David E. Wilkes, Yufeng Wang, Hong Cai, Kathleen Collins, B. Andrew Stewart, Suzanne R. Lee, Katarzyna Wilamowska, Zasha Weinberg, Walter L. Ruzzo, Dorota Wloga, Jacek Gaertig, Joseph Frankel, Che-Chia Tsao, Martin A. Gorovsky, Patrick J. Keeling, Ross F. Waller, Nicola J. Patron, J. Michael Cherry, Nicholas A. Stover, Cynthia J. Krieger, Christina Del Toro, Hilary F. Ryder, Sondra C. Williamson, Rebecca A. Barbeau, Eileen P. Hamilton, Eduardo Orias

Biological Sciences Faculty Research and Publications

The ciliate Tetrahymena thermophila is a model organism for molecular and cellular biology. Like other ciliates, this species has separate germline and soma functions that are embodied by distinct nuclei within a single cell. The germline-like micronucleus (MIC) has its genome held in reserve for sexual reproduction. The soma-like macronucleus (MAC), which possesses a genome processed from that of the MIC, is the center of gene expression and does not directly contribute DNA to sexual progeny. We report here the shotgun sequencing, assembly, and analysis of the MAC genome of T. thermophila, which is approximately 104 Mb in length and …

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Rana Ocellata Linnaeus, 1758 (Currently Leptodactylus Ocellatus; Amphibia, Anura): Proposed Conservation Of Usage Of The Specific Name By The Designation Of A Neotype, W. Ronald Heyer, Ulisses Caramaschi, Rafael O. De Sá Sep 2006

Rana Ocellata Linnaeus, 1758 (Currently Leptodactylus Ocellatus; Amphibia, Anura): Proposed Conservation Of Usage Of The Specific Name By The Designation Of A Neotype, W. Ronald Heyer, Ulisses Caramaschi, Rafael O. De Sá

Biology Faculty Publications

The purpose of this application, under Article 75.6 of the Code, is to conserve the usage of the specific name of Rana ocellata Linnaeus, 1758 for a species of leptodactylid frog from South America by the designation of a neotype. Prevailing usage of the name is threatened by the identity of the type specimen which is a different species than that which is currently known as Leptodactylus ocellatus. It is proposed that all name-bearing types be set aside and a neotype designated in accord with prevailing usage.

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Retrotranspositions In Orthologous Regions Of Closely Related Grass Species, Chunguang Du, Zuzana Swigoňová, Joachim Messing Aug 2006

Retrotranspositions In Orthologous Regions Of Closely Related Grass Species, Chunguang Du, Zuzana Swigoňová, Joachim Messing

Department of Biology Faculty Scholarship and Creative Works

Background: Retrotransposons are commonly occurring eukaryotic transposable elements (TEs). Among these, long terminal repeat (LTR) retrotransposons are the most abundant TEs and can comprise 50-90% of the genome in higher plants. By comparing the orthologous chromosomal regions of closely related species, the effects of TEs on the evolution of plant genomes can be studied in detail. Results: Here, we compared the composition and organization of TEs within five orthologous chromosomal regions among three grass species: maize, sorghum, and rice. We identified a total of 132 full or fragmented LTR retrotransposons in these regions. As a percentage of the total cumulative …

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Interaction Of Ice Storms And Management Practices On Current Carbon Sequestration In Forests With Potential Mitigation Under Future Co2 Atmosphere, Heather R. Mccarthy, Ram Oren, Hyun-Seok Kim, Kurt H. Johnsen, Chris Maier, Seth G. Pritchard, Micheal Davis Aug 2006

Interaction Of Ice Storms And Management Practices On Current Carbon Sequestration In Forests With Potential Mitigation Under Future Co2 Atmosphere, Heather R. Mccarthy, Ram Oren, Hyun-Seok Kim, Kurt H. Johnsen, Chris Maier, Seth G. Pritchard, Micheal Davis

Faculty Publications

[1] Ice storms are disturbance events with potential impacts on carbon sequestration. Common forest management practices, such as fertilization and thinning, can change wood and stand properties and thus may change vulnerability to ice storm damage. At the same time, increasing atmospheric CO2 levels may also influence ice storm vulnerability. Here we show that a nonintensively managed pine plantation experienced a ∼250 g C m−2 reduction in living biomass during a single storm, equivalent to ∼30% of the annual net ecosystem carbon exchange of this ecosystem. Drawing on weather and damage survey data from the entire storm cell, …

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Integration Of Hybridization-Based Markers (Overgos) Into Physical Maps For Comparative And Evolutionary Explorations In The Genus Oryza And In Sorghum, Barbara L. Hass-Jacobus, Montona Futrell-Griggs, Brian Abernathy, Rick Westerman, Jose-Luis Goicoechea, Joshua Stein, Patricia Klein, Bonnie Hurwitz, Bin Zhou, Fariborz Rakhshan, Abhijit Sanyal, Navdeep Gill, Jer-Young Lin, Jason G. Walling, Mei Zhong Luo, Jetty Siva S Ammiraju, Dave Kudrna, Hye Ran Kim, Doreen Ware, Rod A. Wing, Phillip San Miguel, Scott A. Jackson Aug 2006

Integration Of Hybridization-Based Markers (Overgos) Into Physical Maps For Comparative And Evolutionary Explorations In The Genus Oryza And In Sorghum, Barbara L. Hass-Jacobus, Montona Futrell-Griggs, Brian Abernathy, Rick Westerman, Jose-Luis Goicoechea, Joshua Stein, Patricia Klein, Bonnie Hurwitz, Bin Zhou, Fariborz Rakhshan, Abhijit Sanyal, Navdeep Gill, Jer-Young Lin, Jason G. Walling, Mei Zhong Luo, Jetty Siva S Ammiraju, Dave Kudrna, Hye Ran Kim, Doreen Ware, Rod A. Wing, Phillip San Miguel, Scott A. Jackson

Biology Faculty Articles

Background: With the completion of the genome sequence for rice (Oryza sativa L.), the focus of rice genomics research has shifted to the comparison of the rice genome with genomes of other species for gene cloning, breeding, and evolutionary studies. The genus Oryza includes 23 species that shared a common ancestor 8–10 million years ago making this an ideal model for investigations into the processes underlying domestication, as many of the Oryza species are still undergoing domestication. This study integrates high-throughput, hybridization-based markers with BAC end sequence and fingerprint data to construct physical maps of rice chromosome 1 orthologues in …

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Population Divergence In Plasticity Of The Avt System And Its Association With Aggressive Behaviors In A Death Valley Pupfish, Sean C. Lema Aug 2006

Population Divergence In Plasticity Of The Avt System And Its Association With Aggressive Behaviors In A Death Valley Pupfish, Sean C. Lema

Biological Sciences

Behavioral differences can evolve rapidly in allopatry, but little is known about the neural bases of such changes. Allopatric populations of Amargosa pupfish (Cyprinodon nevadensis) vary in aggression and courtship behaviors in the wild. Two of these wild populations were recently found to differ in brain expression of arginine vasotocin (AVT)—a peptide hormone shown previously to modulate aggression in pupfish. These populations have been isolated for less than 4000 years, so it remained unclear whether the differences in behavior and neural AVT phenotype were evolved changes or plastic responses to ecologically dissimilar habitats. Here, I tested whether these …

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The Effects Of Dispersal And Recruitment Limitation On Community Structure Of Odonates In Artificial Ponds, Shannon J. Mccauley Aug 2006

The Effects Of Dispersal And Recruitment Limitation On Community Structure Of Odonates In Artificial Ponds, Shannon J. Mccauley

Biological Sciences

I examined the effects of isolation on the structure of both adult and larval dragonfly (Odonata: Anisoptera) communities forming at physically identical artificial ponds over two years. Isolation, whether measured by distance to the nearest source habitat or by connectivity to multiple sources, was significantly negatively related to the species richness of dragonflies observed at and collected in these ponds. These results indicate that dispersal and recruitment limitation acted as filters on the richness of communities at these artificial ponds. The richness of larval recruits in artificial ponds was lower than the richness of adult dispersers observed at ponds, and …

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Analysis Of Treatment Effects On The Microbial Ecology Of The Human Intestine, Anna L. Engelbrektson, Joshua R. Korzenik, Mary Ellen Sanders, Brian G. Clement, Gregory Leyer, Todd R. Klaenhammer, Christopher L. Kitts Aug 2006

Analysis Of Treatment Effects On The Microbial Ecology Of The Human Intestine, Anna L. Engelbrektson, Joshua R. Korzenik, Mary Ellen Sanders, Brian G. Clement, Gregory Leyer, Todd R. Klaenhammer, Christopher L. Kitts

Biological Sciences

A large number of studies have investigated gastrointestinal microbiota and changes in the gastrointestinal community. However, a concern in these studies is how best to assess changes in gastrointestinal community structure. This paper presents two different human trials where the fecal terminal restriction fragment length polymorphism data sets were analyzed to search for treatment effects. Principle components analysis and cluster analysis based on grouped data are compared with analysis of data by subject using distance coefficients. Comparison with baseline within an individual before grouping by treatment provided a clearer indication of treatment effects than did an evaluation of data grouped …

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Integrated Fisheries Management Draft Allocation Report Roe's Abalone Perth Metropolitan Region., Integrated Fisheries Allocation Advisory Committee Aug 2006

Integrated Fisheries Management Draft Allocation Report Roe's Abalone Perth Metropolitan Region., Integrated Fisheries Allocation Advisory Committee

Fisheries Management Papers

The IFAAC has prepared this report, which documents the committee’s initial position on allocations for the abalone resource, along with the reasons for its conclusions as a basis for widespread community consultation. This report follows the IFAAC’s preliminary investigation of the abalone resourcesharing issues and consultation with stakeholders

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Molecular Population Genetics And Phenotypic Diversification Of Two Populations Of The Thermophilic Cyanobacterium Mastigocladus Laminosus, Scott R. Miller, Michael D. Purugganan, Stephanie E. Curtis Aug 2006

Molecular Population Genetics And Phenotypic Diversification Of Two Populations Of The Thermophilic Cyanobacterium Mastigocladus Laminosus, Scott R. Miller, Michael D. Purugganan, Stephanie E. Curtis

Biological Sciences Faculty Publications

We investigated the distributions of genetic and phenotypic variation for two Yellowstone National Park populations of the heterocyst-forming cyanobacterium Mastigocladus (Fischerella) laminosus that exhibit dramatic phenotypic differences as a result of environmental differences in nitrogen availability. One population develops heterocysts and fixes nitrogen in situ in response to a deficiency of combined nitrogen in its environment, whereas the other population does neither due to the availability of a preferred nitrogen source. Slowly evolving molecular markers, including the 16S rRNA gene and the downstream internal transcribed spacer, are identical among all laboratory isolates from both populations but belie considerable genetic and …

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Role Of The Stable Signal Peptide Of Junín Arenavirus Envelope Glycoprotein In Ph-Dependent Membrane Fusion, Joanne York, Jack H. Nunberg Aug 2006

Role Of The Stable Signal Peptide Of Junín Arenavirus Envelope Glycoprotein In Ph-Dependent Membrane Fusion, Joanne York, Jack H. Nunberg

Biological Sciences Faculty Publications

The envelope glycoprotein of the arenaviruses (GP-C) is unusual in that the mature complex retains the cleaved, 58-amino-acid signal peptide. Association of this stable signal peptide (SSP) has been shown to be essential for intracellular trafficking and proteolytic maturation of the GP-C complex. We identify here a specific and previously unrecognized role of SSP in pH-dependent membrane fusion. Amino acid substitutions that alter the positive charge at lysine K33 in SSP affect the ability of GP-C to mediate cell-cell fusion and the threshold pH at which membrane fusion is triggered. Based on the presumed location of K33 at or near …

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Anti-Viral Activity Of Quillaja Saponaria Molina Extracts Against Hiv-1 And Hiv-2, Jennifer Lee Sprayberry Aug 2006

Anti-Viral Activity Of Quillaja Saponaria Molina Extracts Against Hiv-1 And Hiv-2, Jennifer Lee Sprayberry

Biology Theses - Archive

It has been well established that extracts from the bark of the South American tree Quillaja saponaria Molina have the capacity to stimulate strong immune responses against exogenous antigen when used as an adjuvant. However, the anti-viral capacity of Q. saponins has not been well established. We document the anti-viral capacity of Quillaja saponaria extracts against HIV-1 and HIV-2. The extract appeared to interact with the gp120 subunit of HIV-1 and HIV-2 to produce a low anti-viral effect by blocking viral attachment. The extract was also observed to coat cells in a time dependent manner and block attachment to CD4 …

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Population Genetics Of Phanaeus Vindex And P. Difformis And Congruence With Morphology Across A Geographic Zone Of Species Overlap, Aaron Michael Dickey Aug 2006

Population Genetics Of Phanaeus Vindex And P. Difformis And Congruence With Morphology Across A Geographic Zone Of Species Overlap, Aaron Michael Dickey

Biology Theses - Archive

Amplified Fragment Length Polymorphisms (AFLPs) reveal that the rainbow scarabs Phanaeus vindex (MacLeay) and Phanaeus difformis (LeConte) are distinct evolutionary units which occur in sympatry at the Fort Worth Nature Center. The genetic structure at this location is distinctly bimodal with strong segregation of taxa based on soil type. In addition, certain allele frequencies within P. vindex locations exhibited a significant correlation with a precipitation gradient and other allele frequencies within P. vindex locations were significantly different on loam soil than on both sand and clay soils. Phanaeus vindex and P. difformis exhibit continuous morphological character states between two extremes, …

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Identification And Characterization Of Cellular Targets Of The Bacterial Cytotoxin Yopt In Saccharomyces Cerevisiae, Paul David Caccamo Aug 2006

Identification And Characterization Of Cellular Targets Of The Bacterial Cytotoxin Yopt In Saccharomyces Cerevisiae, Paul David Caccamo

Masters Theses

Human pathogenic Yersinia spp. utilize Type III Secretion to deliver six effector proteins into host cells. The injected proteins resemble eukaryotic signal transduction molecules and are capable of disrupting signaling pathways in order to subvert the functions of the targeted cell or disrupt communication with surrounding cells. As a result, bacterial invaders are not only able to survive the threat of a host immune response, but can thrive despite it. YopT is a cysteine protease that cleaves RhoGTPases, releasing them from the membrane and thus from their role as initiators of signaling pathways, including the nucleation of actin and …

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Disturbance Facilitates Invasion: The Effects Are Stronger Abroad Than At Home, José L. Hierro, Diego Villarreal, Özkan Eren, Jon M. Graham, Ragan M. Callaway Aug 2006

Disturbance Facilitates Invasion: The Effects Are Stronger Abroad Than At Home, José L. Hierro, Diego Villarreal, Özkan Eren, Jon M. Graham, Ragan M. Callaway

Biological Sciences Faculty Publications

Disturbance is one of the most important factors promoting exotic invasion. However, if disturbance per se is sufficient to explain exotic success, then "invasion" abroad should not differ from "colonization" at home. Comparisons of the effects of disturbance on organisms in their native and introduced ranges are crucial to elucidate whether this is the case; however, such comparisons have not been conducted. We investigated the effects of disturbance on the success of Eurasian native Centaurea solstitialis in two invaded regions, California and Argentina, and one native region, Turkey, by conducting field experiments consisting of simulating different disturbances and adding locally …

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Use Of Temperature Sensitive Mutants To Map Reovirus Induced Oncolysis, Ka Ian Tam Aug 2006

Use Of Temperature Sensitive Mutants To Map Reovirus Induced Oncolysis, Ka Ian Tam

Biology Theses - Archive

Reovirus is known to establish persistent infections in normal cells while selectively destroying transformed cells. Individual viruses from each of the ten groups of Reovirus is known to establish persistent infections in normal cells while selectively destroying transformed cells. Individual viruses from each of the ten groups of Reovirus temperature sensitive mutants were used to examine the gene or genes involved in the differential lysis activity. Temperature sensitive mutants were generated by chemical mutagenesis and have one of the ten genes impaired when growing at the non-permissive temperature, while they behave like wild type when growing at the permissive temperature. …

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Chironomid Hemoglobin Genetic Diversity As An Indicator Of The New Jersey Hackensack Meadowlands Wetland Health, Lene Marie De Coursin Jacobs Aug 2006

Chironomid Hemoglobin Genetic Diversity As An Indicator Of The New Jersey Hackensack Meadowlands Wetland Health, Lene Marie De Coursin Jacobs

Seton Hall University Dissertations and Theses (ETDs)

Kearny Marsh located within the Hackensack Meadowlands is a freshwater wetland impacted by multiple environmental stressors from human activity. The marsh is located in the northeastern New Jersey metropolitan area. Chironomid larvae, aquatic larvae of midge fly, were analyzed from two Kearny Marsh sample sites, W9 and W22. A previous sediment analysis and toxicity study characterized heavy metal contaminants the marsh. The data results were applied in this thesis study to determine the correlation between environmental stressors and chironomid genetic diversity. Site W9 sediment was impacted by severe levels of total heavy metal contamination, whereas site W22 had just below …

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Changes In Microbial Community Structure Of Petroleum Contaminated Sediments Are Reflected In Subsurface Geophysical Signatures, Jonathan P. Allen Aug 2006

Changes In Microbial Community Structure Of Petroleum Contaminated Sediments Are Reflected In Subsurface Geophysical Signatures, Jonathan P. Allen

Masters Theses

Petroleum contamination of sediments leads to dynamic changes in the subsurface. These include changes in the microbiota as well as in the subsurface geophysical and geochemical properties. Anomalously high conductivity values observed in subsurface zones contaminated with light non aqueous phase liquids (LNAPLs) have been suggested to be the result of microbial activity. Therefore, we investigated the interdependence between geoelectrical signatures and microbial community structure in petroleum contaminated field sediments and laboratory column experiments. Spatial and temporal changes in electrical conductivity of the subsurface paralleled changes in microbial community composition, with the highest conductivity values concomitant with specific anaerobic hydrocarbon-degrading …

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Characterization Of Membrane Potentials In Vascular Smooth Muscle Of Hagfish, Lamprey And Trout, Prentiss Jones Jr. Aug 2006

Characterization Of Membrane Potentials In Vascular Smooth Muscle Of Hagfish, Lamprey And Trout, Prentiss Jones Jr.

Dissertations

The objective of this study was to characterize membrane potentials in systemic arteries of Pacific hagfish, Eptatretus stouti, Rainbow trout, Onchorhyncus mykiss, and Sea lamprey Petromyzon marinus. Previous studies have characterized membrane potentials in piscine tissue. However, these studies utilized non-vascular tissues such as cardiac muscle and skeletal muscle (69, 161). Characterization of membrane potentials in fish vasculature is without precedent in the literature. The hypothesis of this study was that membrane potentials in fish vascular smooth muscle differ little between species when comparable vasculature is evaluated.

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Notes On Invasive Plants In The Rio Grande Delta Of Cameron County, Texas., Robert I. Lonard, Frank W. Judd Aug 2006

Notes On Invasive Plants In The Rio Grande Delta Of Cameron County, Texas., Robert I. Lonard, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

No abstract provided.

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