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2004

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Biology

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Full-Text Articles in Life Sciences

Episodic Physical Forcing And The Structure Of Phytoplankton Communities In The Coastal Waters Of New Jersey, Mark A. Moline, Shelley M. Blackwell, Robert Chant, Matthew J. Oliver, Trisha Bergmann, Scott Glenn, Oscar M.E. Schofield Dec 2004

Episodic Physical Forcing And The Structure Of Phytoplankton Communities In The Coastal Waters Of New Jersey, Mark A. Moline, Shelley M. Blackwell, Robert Chant, Matthew J. Oliver, Trisha Bergmann, Scott Glenn, Oscar M.E. Schofield

Biological Sciences

The high variability in physical, biological, and chemical properties in coastal waters have limited our ability to sample the appropriate timescale and space scale to resolve physical forcing of the ecosystem. To improve our understanding, a multiplatform adaptive sampling program at the Long-term Ecosystem Observatory(LEO-15) off the coast of New Jersey examined the relationship between episodic summertime upwelling and downwelling events and the corresponding dynamics in bulk phytoplankton biomass and community structure. Inherent and apparent optical properties were concurrently measured to evaluate the use of optics to improve future sampling coverage in coastal regions. Results indicate peak chlorophyll biomass ...


Kinetics And Relative Importance Of Phosphorolytic And Hydrolytic Cleavage Of Cellodextrins And Cellobiose In Cell Extracts Of Clostridium Thermocellum, Yie.-Heng P. Zhang, Lee R. Lynd Dec 2004

Kinetics And Relative Importance Of Phosphorolytic And Hydrolytic Cleavage Of Cellodextrins And Cellobiose In Cell Extracts Of Clostridium Thermocellum, Yie.-Heng P. Zhang, Lee R. Lynd

Open Dartmouth: Faculty Open Access Scholarship

Rates of phosphorolytic cleavage of 􏰁-glucan substrates were determined for cell extracts from Clostridium thermocellum ATCC 27405 and were compared to rates of hydrolytic cleavage. Reactions with cellopentaose and cellobiose were evaluated for both cellulose (Avicel)- and cellobiose-grown cultures, with more limited data also obtained for cellotetraose. To measure the reaction rate in the chain-shortening direction at elevated temper- atures, an assay protocol was developed featuring discrete sampling at 60°C followed by subsequent analysis of reaction products (glucose and glucose-1-phosphate) at 35°C. Calculated rates of phosphorolytic cleavage for cell extract from Avicel-grown cells exceeded rates of hydrolytic cleavage ...


Loss Of Enemy Resistance Among Introduced Populations Of St. John's Wort (Hypericum Perforatum), John L. Maron, Montserrat Vilà, John Arnason Dec 2004

Loss Of Enemy Resistance Among Introduced Populations Of St. John's Wort (Hypericum Perforatum), John L. Maron, Montserrat Vilà, John Arnason

Biological Sciences Faculty Publications

The Evolution of Increased Competitive Ability (EICA) hypothesis predicts that introduced plants should lose enemy resistance and in turn evolve increased size or fecundity. We tested the first prediction of this hypothesis by growing introduced North American and native European genotypes of St. John's Wort (Hypericum perforatum) in common gardens in the state of Washington, USA, and in Girona, Spain. In both gardens we measured levels of hypericin and pseudohypericin (and in Washington, hypericide)— compounds known to be toxic to generalist pathogens and herbivores. In a third common garden, in Spain, we experimentally manipulated native pathogen pressure (by treating ...


Bergmann's Clines In Ectotherms: Illustrating A Life-History Perspective With Sceloporine Lizards, Michael J. Angilletta Jr., Peter H. Niewiarowski, Arthur E. Dunham, Adam D. Leache, Warren P. Porter Dec 2004

Bergmann's Clines In Ectotherms: Illustrating A Life-History Perspective With Sceloporine Lizards, Michael J. Angilletta Jr., Peter H. Niewiarowski, Arthur E. Dunham, Adam D. Leache, Warren P. Porter

Biology Faculty Research

The generality and causes of Bergmann's rule have been debated vigorously in the last few years, but Bergmann's clines are rarely explained in the context of life-history theory. We used both traditional and phylogenetic comparative analyses to explore the causes of latitudinal and thermal clines in the body size of the eastern fence lizard (Sceloporus undulatus). The proximate mechanism for larger body sizes in colder environments is delayed maturation, which results in a greater fecundity but a lower survival to maturity. Life-history theory predicts that a higher survivorship of juveniles in colder environments can favor the evolution of ...


Exogenous Vasotocin Alters Aggression During Agonistic Exchanges In Male Amargosa River Pupfish (Cyprinodon Nevadensis Amargosae), Sean C. Lema, Gabrielle A. Nevitt Dec 2004

Exogenous Vasotocin Alters Aggression During Agonistic Exchanges In Male Amargosa River Pupfish (Cyprinodon Nevadensis Amargosae), Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

Pupfishes in the Death Valley region have rapidly differentiated in social behaviors since their isolation in a series of desert streams, springs, and marshes less than 20,000 years ago. These habitats can show dramatic fluctuations in ecological conditions, and pupfish must cope with the changes by plastic physiological and behavioral responses. Recently, we showed differences among some Death Valley populations in brain expression of arginine vasotocin (AVT). As AVT regulates both hydromineral balance and social behaviors in other taxa, these population differences may indicate adaptive changes in osmoregulatory and/or behavioral processes. To test whether AVT is relevant for ...


The Effects Of Protein Prenylation Inhibitors On Morphogenesis In The Dimorphic Fungus Mucor Racemosus, Tameka L. Watkins Dec 2004

The Effects Of Protein Prenylation Inhibitors On Morphogenesis In The Dimorphic Fungus Mucor Racemosus, Tameka L. Watkins

ETD Collection for AUC Robert W. Woodruff Library

Mucor racemosus is a saprophytic, dimorphic fungus belonging to the order Mucorales. The fungus grows as branching, filamentous mycelia in an aerobic environment, but under anaerobic conditions, in the presence of a fermentable hexose, the fungus exhibits its budding yeast form. Though Mucor species are usually not pathogens, several species, including M. racemosus, are among the various Zygomycetes identified as causing a type of opportunistic fungal disease in humans called mucormycosis.

The objective of this study was to obtain information regarding the effects of protein prenylation inhibitors on morphogenesis in M. racemosus. The prenylation inhibitors used were carvone (250 uJvl ...


Soil Biota Facilitate Exotic Acer Invasions In Europe And North America, Kurt O. Reinhart, Ragan M. Callaway Dec 2004

Soil Biota Facilitate Exotic Acer Invasions In Europe And North America, Kurt O. Reinhart, Ragan M. Callaway

Biological Sciences Faculty Publications

The primary hypothesis for successful exotic plant invasions is that the invaders have escaped the specialist consumers that control them (Enemy Release Hypothesis). However, few studies have rigorously tested this assertion with biogeographical experiments or considered the effects of soil organisms. We tested the Enemy Release Hypothesis and the enhanced role of mutualisms by comparing density patterns of the North American Acer negundo and European A. platanoides trees in their native and nonnative ranges. Invaders that have escaped their natural enemies are predicted to attain greater densities in nonnative than native ranges. To determine whether interactions with soil biota could ...


Distribution Of Chemistry And Sexual Fecundity In The Lichenized-Fungi, Xanthoparmelia Cumberlandia And Xanthoparmelia Coloradoensis On Boulder Mountain, Aquarius Plateau, Ut, Heather Bird Jackson Dec 2004

Distribution Of Chemistry And Sexual Fecundity In The Lichenized-Fungi, Xanthoparmelia Cumberlandia And Xanthoparmelia Coloradoensis On Boulder Mountain, Aquarius Plateau, Ut, Heather Bird Jackson

Theses and Dissertations

Three aspects of Xanthoparmelia cumberlandia and Xanthoparmelia coloradoënsis populations found at two elevations are explored: clustering of secondary chemicals and the resulting implications for taxonomic distinctions, the usefulness of thallus size as an indirect measure of sexual fecundity, and the frequency of sexual reproduction.

First, we use clustering of 46 chemicals produced by X. cumberlandia and X. coloradoënsis to evaluate the adequacy of the current taxonomic distinction between them. Using principal components analysis and UPGMA, we find that the currently recognized species boundaries indicated by the presence of stictic acid in X. cumberlandia and salazinic acid in X. coloradoënsis are ...


Ic138 Is A Wd-Repeat Dynein Intermediate Chain Required For Light Chain Assembly And Regulation Of Flagellar Bending, Triscia W. Hendrickson, Catherine A. Perrone, Paul Griffin, Kristin Wuichet, Joshua Mueller, Pinfen Yang, Mary E. Porter, Winfield S. Sale Dec 2004

Ic138 Is A Wd-Repeat Dynein Intermediate Chain Required For Light Chain Assembly And Regulation Of Flagellar Bending, Triscia W. Hendrickson, Catherine A. Perrone, Paul Griffin, Kristin Wuichet, Joshua Mueller, Pinfen Yang, Mary E. Porter, Winfield S. Sale

Biological Sciences Faculty Research and Publications

Increased phosphorylation of dynein IC IC138 correlates with decreases in flagellar microtubule sliding and phototaxis defects. To test the hypothesis that regulation of IC138 phosphorylation controls flagellar bending, we cloned the IC138 gene. IC138 encodes a novel protein with a calculated mass of 111 kDa and is predicted to form seven WD-repeats at the C terminus. IC138 maps near the BOP5 locus, and bop5-1 contains a point mutation resulting in a truncated IC138 lacking the C terminus, including the seventh WD-repeat. bop5-1 cells display wild-type flagellar beat frequency but swim slower than wild-type cells, suggesting that bop5-1 is altered in ...


Monitoring Activity Of Drosophila Larvae: Impedance & Video Microscopy Measures, Ann Simone Cooper, Robin L. Cooper Dec 2004

Monitoring Activity Of Drosophila Larvae: Impedance & Video Microscopy Measures, Ann Simone Cooper, Robin L. Cooper

Biology Faculty Publications

No abstract provided.


Monitoring Heart Rate In Drosophila Larvae By Various Approaches, Sameera Dasari, Robin L. Cooper Dec 2004

Monitoring Heart Rate In Drosophila Larvae By Various Approaches, Sameera Dasari, Robin L. Cooper

Biology Faculty Publications

No abstract provided.


Monitoring Carbon Dioxide Production By Drosophila Larvae, Robin L. Cooper, D. Nicholas Mcletchie Dec 2004

Monitoring Carbon Dioxide Production By Drosophila Larvae, Robin L. Cooper, D. Nicholas Mcletchie

Biology Faculty Publications

No abstract provided.


Development And Characterization Of Monoclonal Antibodies Directed Against Tanapox Virus, Michael Franz Dec 2004

Development And Characterization Of Monoclonal Antibodies Directed Against Tanapox Virus, Michael Franz

Master's Theses

The initial symptoms of a Tanapoxvirus (TPV) infection are indistinguishable from smallpox, which is caused by variola virus (VV). In the post-9/11 area, reagents that can quickly differentiate a TPV infection from smallpox are very desirable, but currently unavailable. Monoclonal antibodies (mAbs) directed specifically against TPV can be used for this purpose. Six mAbs were developed and characterized that specifically bind to TPV infected owl monkey kidney (OMK) cells, but not uninfected cells. The apparent molecular mass of the TPV protein(s) recognized by 5 mAbs were calculated using the Western blot technique. One mAb demonstrated no binding using ...


Evolution And Phylogeny Of Basal Winged Insects With Emphasis On Mayflies (Ephemeroptera), Thomas H. Ogden Nov 2004

Evolution And Phylogeny Of Basal Winged Insects With Emphasis On Mayflies (Ephemeroptera), Thomas H. Ogden

Theses and Dissertations

Ephemeroptera (mayflies) is a monophyletic group of semi-aquatic pterygote insects, comprising 3083 species, 376 genera, and 37 described families and are present on all continents, excluding Antarctica, being associated with freshwater and brackish water habitats. The order is unique among pterygote insects in possessing functional wings at the penultimate molt (subimago stage), prior to the full development of genitalia; in all other insects the presence of functional wings occurs only after the final molt. The purpose of this dissertation is to use molecular and morphological data, in order to investigate the position of the order Ephemeroptera among other insect orders ...


Density Effects On Growth, Survival And Diet Of June Sucker (Chasmistes Liorus): A Component Allee Effect In An Endangered Species., David Barrett Gonzalez Nov 2004

Density Effects On Growth, Survival And Diet Of June Sucker (Chasmistes Liorus): A Component Allee Effect In An Endangered Species., David Barrett Gonzalez

Theses and Dissertations

Density-dependence is considered one of the most important regulators of population growth, and it has been documented across a wide variety of species. Typically, population growth rate and components thereof decline with increasing density (i.e., negative density-dependence); however, in species that exhibit high population densities and social behavior, positive density-dependence (i.e., Allee effect) may occur at low density. June sucker, a federally endangered lake sucker endemic to Utah Lake, Utah, USA, occurred historically at high density, and it exhibits coordinated feeding behavior. These characteristics indicate a potential for the existence of an Allee effect at current low population ...


Reconstitution Of Copii Vesicle Fusion To Generate A Pre-Golgi Intermediate Compartment, Dalu Xu, Jesse C. Hay Nov 2004

Reconstitution Of Copii Vesicle Fusion To Generate A Pre-Golgi Intermediate Compartment, Dalu Xu, Jesse C. Hay

Biological Sciences Faculty Publications

What is the first membrane fusion step in the secretory pathway? In mammals, transport vesicles coated with coat complex (COP) II deliver secretary cargo to vesicular tubular clusters (VTCs) that ferry cargo from endoplasmic reticulum exit sites to the Golgi stack. However, the precise origin of VTCs and the membrane fusion step(s) involved have remained experimentally intractable. Here, we document in vitro direct tethering and SNARE-dependent fusion of endoplasmic reticulum-derived COPII transport vesicles to form larger cargo containers. The assembly did not require detectable Golgi membranes, preexisting VTCs, or CON function. Therefore, COPII vesicles appear to contain all of ...


Evaluating Forensic Dna Evidence: Essential Elements Of A Competent Defense Review, Dan E. Krane Nov 2004

Evaluating Forensic Dna Evidence: Essential Elements Of A Competent Defense Review, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.


Evidence For And Characterization Of Ca2+ Binding To The Catalytic Region Of Arabidopsis Thaliana Phospholipase Dβ, Xuemin Wang Nov 2004

Evidence For And Characterization Of Ca2+ Binding To The Catalytic Region Of Arabidopsis Thaliana Phospholipase Dβ, Xuemin Wang

Biology Department Faculty Works

Most types of plant phospholipase D (PLD) require Ca2+ for activity, but how Ca2+ affects PLD activity is not well understood. We reported previously that Ca2+ binds to the regulatory C2 domain that occurs in the N terminus of the Ca2+-requiring PLDs. Using Arabidopsis thaliana PLDβ and C2-deleted PLDβ (PLDβcat), we now show that Ca2+ also interacts with the catalytic regions of PLD. PLDβcat exhibited Ca2+-dependent activity, was much less active, and required a higher level of Ca2+ than the full-length PLDβ. Ca2+ binding of the proteins was stimulated by phospholipids; phosphatidylserine was the most effective among those ...


Evidence For And Characterization Of Ca2+ Binding To The Catalytic Region Of Arabidopsis Thaliana Phospholipase Dβ, Xuemin Wang Nov 2004

Evidence For And Characterization Of Ca2+ Binding To The Catalytic Region Of Arabidopsis Thaliana Phospholipase Dβ, Xuemin Wang

Xuemin (Sam) Wang

Most types of plant phospholipase D (PLD) require Ca2+ for activity, but how Ca2+ affects PLD activity is not well understood. We reported previously that Ca2+ binds to the regulatory C2 domain that occurs in the N terminus of the Ca2+-requiring PLDs. Using Arabidopsis thaliana PLDβ and C2-deleted PLDβ (PLDβcat), we now show that Ca2+ also interacts with the catalytic regions of PLD. PLDβcat exhibited Ca2+-dependent activity, was much less active, and required a higher level of Ca2+ than the full-length PLDβ. Ca2+ binding of the proteins was stimulated by phospholipids; phosphatidylserine was the most effective among those ...


Identification And Phenotypic Characterization Of The Cell-Division Protein Cdpa, Eric Altermann, B. Logan Buck, Raul Cano, Todd R. Klaenhammer Nov 2004

Identification And Phenotypic Characterization Of The Cell-Division Protein Cdpa, Eric Altermann, B. Logan Buck, Raul Cano, Todd R. Klaenhammer

Biological Sciences

Analysis of the automated computer annotation of the early draft phase genome of Lactobacillus acidophilus NCFM revealed the previously discovered S-layer gene slpA and an additional partial ORF with weak similarities to S-layer proteins. The entire gene was sequenced to reveal a 1799-bp gene coding for 599 amino acids with a calculated molecular mass of 64.8 kDa. No transcription or translation signals could be determined in close proximity to the 5′-region. However, a strong putative terminator with a free energy of −16.84 kcal/mol was identified directly downstream of the gene. A PSI-Blast analysis showed similarities to ...


The Effects Of Postfire Salvage Logging On Aquatic Ecosystems In The American West, J. R. Karr, Jj Rhodes, Gw Minshall, F. Richard Hauer, R. L. Beschta, C. A. Frissell, D. A. Perry Nov 2004

The Effects Of Postfire Salvage Logging On Aquatic Ecosystems In The American West, J. R. Karr, Jj Rhodes, Gw Minshall, F. Richard Hauer, R. L. Beschta, C. A. Frissell, D. A. Perry

Biological Sciences Faculty Publications

Recent changes in the forest policies, regulations, and laws affecting public lands encourage postfire salvage logging, an activity that all too often delays or prevents recovery. In contrast, the 10 recommendations proposed here can improve the condition of watersheds and aquatic ecosystems.


Is There An Antipredator Blood-Squirting Defense In The Bull Horned Lizard, Phrynosoma Taurus?, George Middendorf Nov 2004

Is There An Antipredator Blood-Squirting Defense In The Bull Horned Lizard, Phrynosoma Taurus?, George Middendorf

Department of Biology Faculty Publications

No abstract provided.


Application Of Genotypic And Phenotypic Analyses To Commerical Probiotic Strain Identity And Relatedness, P.S.M. Yeung, C. L. Kitts, R. Cano, P. Tong Nov 2004

Application Of Genotypic And Phenotypic Analyses To Commerical Probiotic Strain Identity And Relatedness, P.S.M. Yeung, C. L. Kitts, R. Cano, P. Tong

Biological Sciences

Aims: The objective of this study was to generate strain-specific genomic patterns of a bank of 67 commercial and reference probiotic strains, with a focus on probiotic lactobacilli.

Methods and Results: Pulsed-field gel electrophoresis (PFGE) was used as the primary method for strain differentiation. This method was compared with carbohydrate fermentation analysis. To supplement visual comparison, PFGE patterns were analysed quantitatively by cluster analysis using unweighted pair group method with arithmetic averages. SmaI, NotI and XbaI were found to effectively generate clear and easy-to-interpret PFGE patterns of a range of probiotic strains. Some probiotic strains from different sources shared highly ...


Alteration Of The Food Web Along The Antarctic Peninsula In Response To A Regional Warming Trend, Mark A. Moline, Herve Claustre, Thomas K. Frazer, Oscar Schofield, Maria Vernet Nov 2004

Alteration Of The Food Web Along The Antarctic Peninsula In Response To A Regional Warming Trend, Mark A. Moline, Herve Claustre, Thomas K. Frazer, Oscar Schofield, Maria Vernet

Biological Sciences

In the nearshore coastal waters along the Antarctic Peninsula, a recurrent shift in phytoplankton community structure, from diatoms to cryptophytes, has been documented. The shift was observed in consecutive years (1991–1996) during the austral summer and was correlated in time and space with glacial melt-water runoff and reduced surface water salinities. Elevated temperatures along the Peninsula will increase the extent of coastal melt-water zones and the seasonal prevalence of cryptophytes. This is significant because a change from diatoms to cryptophytes represents a marked shift in the size distribution of the phytoplankton community, which will, in turn, impact the zooplankton ...


Application Of Genotypic And Phenotypic Analyses To Commercial Probiotic Strain Identity And Relatedness, P. S. M. Yeung, Christopher L. Kitts, Phillip S. Tong, M. E. Sanders Nov 2004

Application Of Genotypic And Phenotypic Analyses To Commercial Probiotic Strain Identity And Relatedness, P. S. M. Yeung, Christopher L. Kitts, Phillip S. Tong, M. E. Sanders

Biological Sciences

Aims: The objective of this study was to generate strain-specific genomic patterns of a bank of 67 commercial and reference probiotic strains, with a focus on probiotic lactobacilli.
Methods and Results: Pulsed-field gel electrophoresis (PFGE) was used as the primary method for strain differentiation. This method was compared with carbohydrate fermentation analysis. To supplement visual comparison, PFGE patterns were analysed quantitatively by cluster analysis using unweighted pair group method with arithmetic averages. SmaI, NotI and XbaI were found to effectively generate clear and easy-to-interpret PFGE patterns of a range of probiotic strains. Some probiotic strains from different sources shared highly ...


Sex Differences In Metabolic Rates In Field Crickets And Their Dipteran Parasitoids, Gita R. Kolluru, Mark A. Chappell, Marlene Zuk Nov 2004

Sex Differences In Metabolic Rates In Field Crickets And Their Dipteran Parasitoids, Gita R. Kolluru, Mark A. Chappell, Marlene Zuk

Biological Sciences

Sex differences in metabolic rate (MR) can result from dimorphism in the performance of energetically demanding activities. Male crickets (Teleogryllus oceanicus) engage in costly calling and aggressive activity not performed by females. Consistent with this difference, we found higher maximal MR, factorial scope, and fat content in males than females. T. oceanicus song is also costly because it attracts the parasitoid fly Ormia ochracea. Parasitized crickets had reduced maximal MR consistent with a metabolic cost to harboring larvae. This cost was greater for females, either because females invest more heavily into reproduction at the expense of metabolic capacity, or because ...


Filarial Genomics, Steven A. Williams Nov 2004

Filarial Genomics, Steven A. Williams

Biological Sciences: Faculty Publications

No abstract provided.


Patterns Of Fitness And Fluctuating Asymmetry Across A Broad Hybrid Zone, Mitchell B. Cruzan Nov 2004

Patterns Of Fitness And Fluctuating Asymmetry Across A Broad Hybrid Zone, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

We estimated levels of developmental instability in leaves, as indicated by fluctuating asymmetry (i.e., random deviations from perfect bilateral symmetry), across a broad hybrid zone between two taxa in the Piriqueta caroliniana complex. Previous studies have indicated that this hybrid zone was initiated in southern Florida and has expanded northward. We found that plants from the hybrid zone generally had higher levels of leaf developmental instability than plants from allopatric regions, but the increase in asymmetry was not substantial. Although it is usually assumed that developmental instability is associated with lower fitness, these Piriqueta hybrids from central Florida are ...


Is There An Antipredator Blood-Squirting Defense In The Bull Horned Lizard, Phrynosoma Taurus?, George Middendorf Oct 2004

Is There An Antipredator Blood-Squirting Defense In The Bull Horned Lizard, Phrynosoma Taurus?, George Middendorf

George Middendorf

No abstract provided.


Evaluating Forensic Dna Evidence, Dan E. Krane Oct 2004

Evaluating Forensic Dna Evidence, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.