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2003

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Articles 1 - 30 of 336

Full-Text Articles in Biology

The Zebrafish Iguana Locus Encodes Dzip1, A Novel Zinc Finger Protein Required For Proper Regulation Of Hedgehog Signaling, Kohshin Sekimizu, Noriyuki Nishioka, Hiroshi Sasaki, Hiroyuki Takeda, Rolf O. Karlstrom, Atsushi Kawakami Dec 2003

The Zebrafish Iguana Locus Encodes Dzip1, A Novel Zinc Finger Protein Required For Proper Regulation Of Hedgehog Signaling, Kohshin Sekimizu, Noriyuki Nishioka, Hiroshi Sasaki, Hiroyuki Takeda, Rolf O. Karlstrom, Atsushi Kawakami

Rolf O Karlstrom

Members of the Hedgehog (Hh) family of intercellular signaling molecules play crucial roles in animal development. Aberrant regulation of Hh signaling in humans causes developmental defects, and leads to various genetic disorders and cancers. We have characterized a novel regulator of Hh signaling through the analysis of the zebrafish midline mutant iguana (igu). Mutations in igu lead to reduced expression of Hh target genes in the ventral neural tube, similar to the phenotype seen in zebrafish mutants known to affect Hh signaling. Contradictory at first sight, igu mutations lead to expanded Hh target gene expression in somites. Genetic and pharmacological …


Thermodynamic Characterization Of The Binding Of Activator Of G Protein Signaling 3 (Ags3) And Peptides Derived From Ags3 With G Alpha I1, Anirban Adhikari, Stephen R. Sprang Dec 2003

Thermodynamic Characterization Of The Binding Of Activator Of G Protein Signaling 3 (Ags3) And Peptides Derived From Ags3 With G Alpha I1, Anirban Adhikari, Stephen R. Sprang

Biological Sciences Faculty Publications

Activator of G protein signaling 3 (AGS3) is a guanine nucleotide dissociation inhibitor (GDI) that contains four G protein regulatory (GPR) or GoLoco motifs in its C-terminal domain. The entire C-terminal domain (AGS3-C) as well as certain peptides corresponding to individual GPR motifs of AGS3 bound to G alpha i1 and inhibited the binding of GTP by stabilizing the GDP-bound conformation of G alpha i1. The stoichiometry, free energy, enthalpy, and dissociation constant for binding of AGS3-C to G alpha i1 were determined using isothermal titration calorimetry. AGS3-C possesses two apparent high affinity (Kd approximately 20 nm) and two apparent …


A Comparison Of Bioaccumulation And Digestive Enzyme Solubilization Of Copper In Two Species Of Sea Cucumbers With Different Feeding Habits., John W. Bundridge Dec 2003

A Comparison Of Bioaccumulation And Digestive Enzyme Solubilization Of Copper In Two Species Of Sea Cucumbers With Different Feeding Habits., John W. Bundridge

Electronic Theses and Dissertations

The mode of feeding exhibited by different organisms may influence the form or quantity of copper that is bioaccumulated. This hypothesis has been tested by exposing 2 species of sea cucumbers, Pentacta anceps and Stichopus chloronotus, which possess different feeding modes, to varying concentrations of copper.

The digestive tract and body wall were dissected and analyzed for copper concentration using atomic absorption spectroscopy. A trend was present, exhibiting a small dose dependent curve. The results did not show a significant difference between species or treatments. This study indicates that feeding mode may influence the amount of copper accumulated but …


Body Mass Of Late Quaternary Mammals (Data Set), Felisa A. Smith, S. Kathleen Lyons, S.K. Morgan Ernest, Kate E. Jones, Kansas State University, Tamar Dayan, Pablo A. Marquet, James H. Brown, John P. Haskell Dec 2003

Body Mass Of Late Quaternary Mammals (Data Set), Felisa A. Smith, S. Kathleen Lyons, S.K. Morgan Ernest, Kate E. Jones, Kansas State University, Tamar Dayan, Pablo A. Marquet, James H. Brown, John P. Haskell

School of Biological Sciences: Faculty Publications

The purpose of this data set was to compile body mass information for all mammals on Earth so that we could investigate the patterns of body mass seen across geographic and taxonomic space and evolutionary time. We were interested in the heritability of body size across taxonomic groups (How conserved is body mass within a genus, family, and order?), in the overall pattern of body mass across continents (Do the moments and other descriptive statistics remain the same across geographic space?), and over evolutionary time (How quickly did body mass patterns iterate on the patterns seen today? Were the Pleistocene …


Heat-Shock Protein 70 (Hsp70) As A Biochemical Stress Indicator: An Experimental Field Test In Two Congeneric Intertidal Gastropods (Genus: Tegula), Lars Tomanek, Eric Sanford Dec 2003

Heat-Shock Protein 70 (Hsp70) As A Biochemical Stress Indicator: An Experimental Field Test In Two Congeneric Intertidal Gastropods (Genus: Tegula), Lars Tomanek, Eric Sanford

Biological Sciences

Although previous studies have demonstrated that heat-shock protein 70 (Hsp70) can be induced by environmental stress, little is known about natural variation in this response over short time scales. We examined how Hsp70 levels varied over days to weeks in two intertidal snail species of the genus Tegula. Sampling was conducted both under naturally changing environmental conditions and in different vertical zones on a rocky shore. The subtidal to low-intertidal T. brunnea was transplanted into shaded and unshaded mid-intertidal cages to assess temporal variation in Hsps under conditions of increased stress. For comparison, the low to mid-intertidal ,T. …


Antipredator Behavior And Physiology Determine Lestes Species Turnover Along The Pond-Permanence Gradient, Robby Stoks, Mark A. Mcpeek Dec 2003

Antipredator Behavior And Physiology Determine Lestes Species Turnover Along The Pond-Permanence Gradient, Robby Stoks, Mark A. Mcpeek

Dartmouth Scholarship

Identifying key traits that shape trade-offs that restrict species to only a subset of environmental gradients is crucial to understanding and predicting species turnover. Previous field experiments have shown that larvae of Lestes damselfly species segregate along the entire gradient of pond permanence and predator presence and that differential predation risk and life history constraints together shape their distribution. Here, we report laboratory experiments that identify key differences in behavior and physiology among species that structure their distributions along this gradient. The absence of adaptive antipredator behavioral responses against large dragonfly larvae and fish of Lestes dryas, the only species …


From Biology To Consciousness To Morality, Ursula Goodenough, Terrence W. Deacon Dec 2003

From Biology To Consciousness To Morality, Ursula Goodenough, Terrence W. Deacon

Biology Faculty Publications & Presentations

Social animals are provisioned with prosocial orientations that operate to transcend self-interest. Morality, as used here, describes human versions of such orientations. We explore the evolutionary antecedents of morality in the context of emergentism, giving considerable attention to the biological traits that undergird awareness and our emergent human forms of mind. We suggest that our moral frames of mind emerge from our primate prosocial capacities, transfigured and valenced by our symbolic languages, cultures, and religions.

Portions of this article were given by Deacon in a paper at the forty-ninth annual conference of IRAS, “Is Nature Enough? The Thirst for …


Left-Sided Directional Bias Of Cloacal Contacts During House Sparrow Copulations, Karen B. Nyland, Michael P. Lombardo, Patrick A. Thorpe Dec 2003

Left-Sided Directional Bias Of Cloacal Contacts During House Sparrow Copulations, Karen B. Nyland, Michael P. Lombardo, Patrick A. Thorpe

Peer Reviewed Publications

Most female birds have only a left ovary and associated oviduct. The entry to the oviduct is on the left side of the urodeum of the cloaca. This arrangement may favor males that mount females from the left during copulation if it results in sperm being placed closer to the opening of the oviduct. Therefore, we predicted a left-sided directional bias of cloacal contacts during House Sparrow (Passer domesticus) copulations. Cloacal contacts from the left outnumbered those from the right 74 to 25 (3:1) during 25 bouts of copulation at 11 House Sparrow nests. While this pattern suggests …


Mitogenic Effect Of Bartonella Bacilliformis On Human Vascular Endothelial Cells And Involvement Of Groel, Michael F. Minnick, Laura S. Smitherman, D. Scott Samuels Dec 2003

Mitogenic Effect Of Bartonella Bacilliformis On Human Vascular Endothelial Cells And Involvement Of Groel, Michael F. Minnick, Laura S. Smitherman, D. Scott Samuels

Biological Sciences Faculty Publications

Bartonellae are bacterial pathogens for a wide variety of mammals. In humans, bartonellosis can result in angioproliferative lesions that are potentially life threatening to the patient, including bacillary angiomatosis, bacillary peliosis, and verruga peruana. The results of this study show that Bartonella bacilliformis, the agent of Oroya fever and verruga peruana, produces a proteinaceous mitogen for human vascular endothelial cells (HUVECs) that acts in a dose-dependent fashion in vitro with maximal activity at >72 h of exposure and results in a 6- to 20-fold increase in cell numbers relative to controls. The mitogen increases bromodeoxyuridine (BrdU) incorporation into HUVECs …


Development Of A Method For Determining Antioxidant Efficacy Against Hydroxyl Radicals, Cherie Hacker Dec 2003

Development Of A Method For Determining Antioxidant Efficacy Against Hydroxyl Radicals, Cherie Hacker

Masters Theses

Hydroxyl free radicals are biologically important molecules in that they attack proteins, lipids and DNA to obtain an electron to fill their outer valence shell. The consequences of such attacks include protein degradation, lipid peroxidation and DNA damage, which leads to many diseases and cancer. While there are many antioxidant assays available to predict anti-radical properties of compounds against different free radicals, the assessment of hydroxyl radical damage has been challenging. This is due to the extremely high reaction rate of hydroxyl radicals. The present study defines an in vitro assay that quantitatively detects antioxidant efficacy against hydroxyl free radicals, …


Proopiomelanocortin Physiological Roles: Pituitary Versus Hypathalamic Functions, James L. Smart Dec 2003

Proopiomelanocortin Physiological Roles: Pituitary Versus Hypathalamic Functions, James L. Smart

Faculty Publications - Department of Biological & Molecular Science

The fact that the proopiomelanocortin (POMC) gene is a critical component of energy homeostasis and the stress response, two distinct yet not exclusively separate biological functions, distinguishes this gene as very intriguing and unique for st lllldy. The POMC gene encodes a preprohormone that is post-translationally processed into multiple bioactive peptides. The tissue specific regulation and tissue specific post-translational modifications provide a means for the broad spectrum of the gene's biological activities. Understanding the POMC gene's cell-specific regulation and the physiological functions of its encoded peptides has been an ongoing project of multiple labs spanning the last two decades. Initial …


K+- Induced Dilation Of Cremasteric Arterioles Involves Na+/K+Atpase And Inward Rectifier K+ Channels, Wendy Burns Dec 2003

K+- Induced Dilation Of Cremasteric Arterioles Involves Na+/K+Atpase And Inward Rectifier K+ Channels, Wendy Burns

Dissertations

The purpose of this study was to evaluate the possible mechanisms involved in cremasteric arteriolar dilation as a result of increased concentrations of ([K+]o) extracellular potassium. Many other studies suggested that Na+/K+ ATPase or KIR channels are responsible for potassium-induced vasodilation in other systems (2, 12, 22, 40, 46, 52, 16, 17, 25, 33, 34, 85, 99, 151). However, these studies show only partial inhibition of dilation as a result of independent blockageof each mechanism. The hypothesis of this study was that both mechanisms contribute to potassium-induced dilation seen in cremasteric arterioles. …


Dynein’S Binding Ability To Microtubules In Budding Yeast Saccharomyces Cerevisiae, Gregory Lyle Waltz Dec 2003

Dynein’S Binding Ability To Microtubules In Budding Yeast Saccharomyces Cerevisiae, Gregory Lyle Waltz

Masters Theses

Cytoplasmic dynein is a minus-end directed microtubule motor that recently has been described as a member of the AAA+ ATPase family. Dyn1p contains four ATP-binding consensus sequences. To understand the role of each ATP-binding site we have begun to systematically mutate the consensus sequence at each ATP-binding site. Thirty-two mutant alleles have been constructed and integrated into the yeast Saccharomyces cerevisiae. We have examined each mutant for ability to grow in rich media, to produce binucleate cells at 12°C, ability to grow in the absence of CIN8, and ability of Dyn1p to bind microtubules. Attempts to localize …


Genetic Locus And Structural Characterization Of The Biochemical Defect In The O-Antigenic Polysaccharide Of The Symbiotically Deficient Rhizobium Etli Mutant, Ce166, Lennart Scott Forsberg, K. Dale Noel, Jodie M. Box, Russell W. Carlson Dec 2003

Genetic Locus And Structural Characterization Of The Biochemical Defect In The O-Antigenic Polysaccharide Of The Symbiotically Deficient Rhizobium Etli Mutant, Ce166, Lennart Scott Forsberg, K. Dale Noel, Jodie M. Box, Russell W. Carlson

Biological Sciences Faculty Research and Publications

The O-antigen polysaccharide (OPS) of Rhizobium etli CE3 lipopolysaccharide (LPS) is linked to the core oligosaccharide via an N-acetylquinovosaminosyl (QuiNAc) residue. A mutant of CE3, CE166, produces LPS with reduced amounts of OPS, and a suppressed mutant, CE166α, produces LPS with nearly normal OPS levels. Both mutants are deficient in QuiNAc production. Characterization of OPS from CE166 and CE166α showed that QuiNAc was replaced by its 4-keto derivative, 2-acetamido-2,6-dideoxyhexosyl-4-ulose. The identity of this residue was determined by NMR and mass spectrometry, and by gas chromatography-mass spectrometry analysis of its 2-acetamido-4-deutero-2,6-dideoxyhexosyl derivatives produced by reduction of the 4-keto group using …


Breeding Distribution And Habitat Use Of Audubon's Oriole In The Lower Rio Grande Valley Of Texas, Steven Gerald Monk Dec 2003

Breeding Distribution And Habitat Use Of Audubon's Oriole In The Lower Rio Grande Valley Of Texas, Steven Gerald Monk

Theses and Dissertations - UTB/UTPA

Audubon's Oriole ( Icterus graduacauda ) was known historically throughout the Lower Rio Grande Valley (LRGV) of Texas, but its breeding range has now declined to mainly riparian habitat in Starr County. Habitat loss, degradation, and fragmentation, and brood parasitism by Bronzed Cowbirds ( Molothrus aeneus ) are likely causes of this decline. Habitat patches where Audubon's Orioles were present were larger, with a larger vertical range of canopy, greater vegetation volume, greater richness of bird and woody plant species, less local deforestation, and less local habitat fragmentation than where Audubon's Orioles were absent. Bronzed Cowbirds showed no numeric correlation …


Yeast Oxa1 Interacts With Mitochondrial Ribosomes: The Importance Of The C‐Terminal Region Of Oxa1, Lixia Jia, Mary Kathryn Dienhart, Mark Schramp, Matthew Mccauley, Kai Hell, Rosemary A. Stuart Dec 2003

Yeast Oxa1 Interacts With Mitochondrial Ribosomes: The Importance Of The C‐Terminal Region Of Oxa1, Lixia Jia, Mary Kathryn Dienhart, Mark Schramp, Matthew Mccauley, Kai Hell, Rosemary A. Stuart

Biological Sciences Faculty Research and Publications

The yeast mitochondrial Oxa1 protein is a member of the conserved Oxa1/YidC/Alb3 protein family involved in the membrane insertion of proteins. Oxa1 mediates the insertion of proteins (nuclearly and mitochondrially encoded) into the inner membrane. The mitochondrially encoded substrates interact directly with Oxa1 during their synthesis as nascent chains and in a manner that is supported by the associated ribosome. We have investigated if the Oxa1 complex interacts with the mitochondrial ribosome. Evidence to support a physical association between Oxa1 and the large ribosomal subunit is presented. Our data indicate that the matrix‐exposed C‐terminal region of Oxa1 plays an important …


Continuous Hyperspectral Absorption Measurements Of Colored Dissolved Organic Material In Aquatic Systems, Gary J. Kirkpatrick, Cristina Orrico, Mark A. Moline, Matthew Oliver, Oscar M. Schofield Nov 2003

Continuous Hyperspectral Absorption Measurements Of Colored Dissolved Organic Material In Aquatic Systems, Gary J. Kirkpatrick, Cristina Orrico, Mark A. Moline, Matthew Oliver, Oscar M. Schofield

Biological Sciences

The majority of organic carbon in the oceans is present as dissolved organic matter (DOM); therefore understanding the distribution and dynamics of DOM is central to understanding global carbon cycles. Describing the time-space variability in colored dissolved organic matter (CDOM) has been difficult, as standard spectrophotometric methods for CDOM determination are laborious and susceptible to methodological biases. Previously, measurements of CDOM absorption in discrete water samples by use of a liquid-waveguide capillary cell (LWCC) compared favorably with measurements made with a benchtop spectrophotometer. Given this, we focused on automating the LWCC technique to improve our spatial and temporal sampling capabilities …


Deep-Slab Fuel Extremophilic Archaea On A Mariana Forearc Serpentinite Mud Volcano: Ocean Drilling Program Leg 195, Michael J. Mottl, Stephen C. Komor, Patricia Fryer, Craig L. Moyer Nov 2003

Deep-Slab Fuel Extremophilic Archaea On A Mariana Forearc Serpentinite Mud Volcano: Ocean Drilling Program Leg 195, Michael J. Mottl, Stephen C. Komor, Patricia Fryer, Craig L. Moyer

Biology Faculty and Staff Publications

As the Pacific plate subducts beneath the Mariana forearc it releases water that hydrates the overlying mantle wedge, converting it to serpentinite that protrudes to form mud volcanoes at the seafloor. Excess H2O ascends through these mud volcanoes and exits as cold springs at their summits. The composition of this deep-slab derived water has been determined by drilling on two of these seamounts. It has a pH of 12.5 and, relative to seawater, is enriched in sulfate, alkalinity, Na/Cl, K, Rb, B, light hydrocarbons, ammonia, 18O, and deuterium, and depleted in chloride, Mg, Ca, Sr, Li, Si, …


Comprehensive Analysis Of Class I And Class Ii Hla Antigens And Chronic Hepatitis B Virus Infection, Chloe L. Thio, David L. Thomas, Peter Karacki, Xiaojiang Gao, Darlene Marti, Richard A. Kaslow, James J. Goedert, Margaret Hilgartner, Steffanie A. Strathdee, Priya Duggal, Stephen J. O'Brien, Jacquie Astemborski, Mary Carrington Nov 2003

Comprehensive Analysis Of Class I And Class Ii Hla Antigens And Chronic Hepatitis B Virus Infection, Chloe L. Thio, David L. Thomas, Peter Karacki, Xiaojiang Gao, Darlene Marti, Richard A. Kaslow, James J. Goedert, Margaret Hilgartner, Steffanie A. Strathdee, Priya Duggal, Stephen J. O'Brien, Jacquie Astemborski, Mary Carrington

Biology Faculty Articles

Following an acute hepatitis B virus (HBV) infection, clearance or persistence is determined in part by the vigor and breadth of the host immune response. Since the human leukocyte antigen system (HLA) is an integral component of the immune response, we hypothesized that the highly polymorphic HLA genes are key determinants of viral clearance. HLA class I and II genes were molecularly typed in 194 Caucasian individuals with viral persistence and 342 matched controls who had cleared the virus. A single class I allele, A*0301 (odds ratio [OR], 0.47; 95% confidence interval [CI], 0.30 to 0.72; P = 0.0005) was …


Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral, Amit Singh, Kwang-Wook Choi Nov 2003

Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral, Amit Singh, Kwang-Wook Choi

Biology Faculty Publications

Dorsoventral (DV) patterning is crucial for eye development in invertebrates and higher animals. DV lineage restriction is the primary event in undifferentiated early eye primordia of Drosophila. InDrosophila eye disc, a dorsal-specific GATA family transcription factor pannier (pnr) controls Iroquois-Complex (Iro-C) genes to establish the dorsal eye fate whereas Lobe (L), which is involved in controlling a Notch ligand Serrate (Ser), is specifically required for ventral growth. However, fate of eye disc cells before the onset of dorsal expression of pnr and Iro-C is not known. We show that L/Ser …


Habitat Use Of Sympatrically Nesting Fish Crows And American Crows, Brook Lauro, John Tanacredi Ph.D. Nov 2003

Habitat Use Of Sympatrically Nesting Fish Crows And American Crows, Brook Lauro, John Tanacredi Ph.D.

Faculty Works: CERCOM

We examined habitat use of sympatric Fish Crows (Corvus ossifragus) and American Crows (C. brachyrhynchos) nesting in the vicinity of waterbird breeding locations at the Rockaway Peninsula, New York City. Fish Crows nested significantly more often at natural habitats, including coastal dunes and salt marsh islands; American Crows nested significantly more often at residential and recreational areas. In regard to potential foraging areas, Fish Crows nested closer to waterbird colonies and to the water's edge while American Crows nested closer to a garbage source and to lawns. Fish Crows nested significantly more often in deciduous trees …


Aada Confers Streptomycin Resistance In Borrelia Burgdorferi, Kristi L. Frank, Sharyl F. Bundle, Michele E. Kresge, Christian H. Eggers, D. Scott Samuels Nov 2003

Aada Confers Streptomycin Resistance In Borrelia Burgdorferi, Kristi L. Frank, Sharyl F. Bundle, Michele E. Kresge, Christian H. Eggers, D. Scott Samuels

Biological Sciences Faculty Publications

To enhance genetic manipulation of the Lyme disease spirochete Borrelia burgdorferi, we assayed the aadA gene for the ability to confer resistance to the antibiotics spectinomycin and streptomycin. Using the previously described pBSV2 as a backbone, a shuttle vector, termed pKFSS1, which carries the aadA open reading frame fused to the B. burgdorferi flgB promoter was constructed. The hybrid flgB promoter-aadA cassette confers resistance to spectinomycin and streptomycin in both B. burgdorferi and Escherichia coli. pKFSS1 has a replication origin derived from the 9-kb circular plasmid and can be comaintained in B. burgdorferi with extant shuttle vector pCE320, which has …


Recovery Of Vegetation Following A Wild Fire On The Margins Of Tidal Flats, Padre Island National Seashore, Texas, Robert I. Lonard, Frank W. Judd, Elizabeth H. Smith Nov 2003

Recovery Of Vegetation Following A Wild Fire On The Margins Of Tidal Flats, Padre Island National Seashore, Texas, Robert I. Lonard, Frank W. Judd, Elizabeth H. Smith

Biology Faculty Publications and Presentations

Recovery of halophytic vegetation on the margin of tidal flats following a wildfire at Padre Island National Seashore, Texas, was studied for 26 months. Species richness, species diversity, species importance, evenness and vegetation abundance were evaluated. Species richness and diversity were restored within 108 days after the fire. Sporobolus virginicus was the dominant species on both burned and non-burned transects. Vegetative cover was slow to recover. It took 19 months for cover of burned areas to equal or exceed cover of non-burned areas. Biomass also was slow to recover and it did not equal biomass of non-burned transects in 26 …


Convergent Habitat Segregation Of Aedes Aegypti And Aedes Albopictus (Diptera : Culicidae) In Southeastern Brazil And Florida, Marieta A H Braks, Ricardo Lourenco-De-Oliveira, Steven A. Juliano, Nildimar A. Honorio, L Philip Lounibos Nov 2003

Convergent Habitat Segregation Of Aedes Aegypti And Aedes Albopictus (Diptera : Culicidae) In Southeastern Brazil And Florida, Marieta A H Braks, Ricardo Lourenco-De-Oliveira, Steven A. Juliano, Nildimar A. Honorio, L Philip Lounibos

Faculty Publications – Biological Sciences

During the rainy season of 2001, the incidence of the dengue vectors Aedes aegypti and Ae. albopictus was examined in different habitats of two cities (Rio de Janeiro and Nova Iguacu) in Rio de Janeiro State, Brazil, and in two cities (Palm Beach and Boca Raton) in Florida. Oviposition trap collections were performed in urban, suburban, and rural habitats in both areas. Our hypothesis that the abundances and frequencies of occurrence of Ae. aegypti and Ae albopictus are affected in opposite ways by increasing urbanization was only partially supported. City, habitat, and their interaction significantly affected the abundance of both …


Wing Shape In House Finches Differs Relative To Migratory Habit In Eastern And Western North America, Jeremy R. Egbert, James R. Belthoff Nov 2003

Wing Shape In House Finches Differs Relative To Migratory Habit In Eastern And Western North America, Jeremy R. Egbert, James R. Belthoff

Biology Faculty Publications and Presentations

We investigated whether wing morphology differed between the sedentary House Finches (Carpodacus mexicanus) of western North America and the introduced population of eastern North America, as the latter has developed migratory behavior since its inception. Wing morphology differed between eastern and western House Finches. Eastern House Finches had shorter proximal primaries and a longer outer primary, perhaps reflecting a thinner and more pointed wing, although no disparity in wing length was detected. Since we interpret these differences in wing shape as modifications for flight capability, we believe that initial evidence for morphological divergence relative to migratory habit between eastern and …


Djungarian Hamsters Exhibit Temperature-Dependent Dietary Fat Choice In Long Days, Sara Hiebert Burch, Kelley Carl Hauser , '99, Abbas Ebrahim , '00 Nov 2003

Djungarian Hamsters Exhibit Temperature-Dependent Dietary Fat Choice In Long Days, Sara Hiebert Burch, Kelley Carl Hauser , '99, Abbas Ebrahim , '00

Biology Faculty Works

Previous studies have shown that whole-animal thermal responses of ectotherms and heterotherms (e.g., hibernators), both of which experience a wide range of body temperatures, are related to the saturation level of somatic lipids, which in turn can be influenced by the ratio of saturated and unsaturated fatty acids in the diet. This study demonstrates that Djungarian hamsters held in long days display ambient temperature dependent choice of dietary fats, increasing their preference for saturated fats when ambient temperature increases ( to 27 degreesC) and later reversing this preference when ambient temperature is returned to its original value ( 8 degreesC). …


Morphology Of The Midgut Trunk In The Penaeid Shrimp, Sicyonia Ingentis, Highlighting Novel Nuclear Pore Particles And Fixed Hemocytes., Gary G. Martin, Alice Chiu Oct 2003

Morphology Of The Midgut Trunk In The Penaeid Shrimp, Sicyonia Ingentis, Highlighting Novel Nuclear Pore Particles And Fixed Hemocytes., Gary G. Martin, Alice Chiu

Gary Martin

The morphology of the midgut trunk (MGT) in the penaeid shrimp Sicyonia ingentis was examined by light and scanning and transmission electron microscopy. Although the function of the MGT is poorly understood, it is not involved with the digestion and absorption of nutrients, and it appears to be the surface of a shrimp least protected from penetration by potential pathogens. As described for other decapod crustaceans, the MGT in shrimp is composed of a simple columnar epithelium separated from a layer of connective tissue by a thick basal lamina. Beneath the basal lamina is a previously unreported layer of hemocytes, …


Ecological Genetics Of Melaleuca Quinquenervia (Myrtaceae) : Population Variation In Florida And Its Influence On Performance Of The Biological Control Agent Oxyops Vitiosa (Coleoptera: Curculionidae), F. Allen Dray Jr. Oct 2003

Ecological Genetics Of Melaleuca Quinquenervia (Myrtaceae) : Population Variation In Florida And Its Influence On Performance Of The Biological Control Agent Oxyops Vitiosa (Coleoptera: Curculionidae), F. Allen Dray Jr.

FIU Electronic Theses and Dissertations

Melaleuca quinquenervia (Cav.) Blake (Myrtaceae) was imported into Florida from Australia over a century ago as a landscape plant. A favorable climate and periodic wildfires helped M. quinquenervia thrive; it now occupies about 200,000 hectares in southern Florida. A biological control (i.e., biocontrol) program against M. quinquenervia has been initiated, but not all biocontrol releases are successful. Some scientists have argued that poor biocontrol agent success may relate to genetic differences among populations of invasive weeds. I tested this premise by determining (1) the number and origins of M. quinquenervia introductions into Florida, (2) whether multiple introduction events resulted in …


Nutrient Cycling In Alaskan Tundra In Response To Experimental Manipulation Of Growing Season Length And Soil Temperature : A Climate Change Scenario, Lorraine E. Ahlquist Oct 2003

Nutrient Cycling In Alaskan Tundra In Response To Experimental Manipulation Of Growing Season Length And Soil Temperature : A Climate Change Scenario, Lorraine E. Ahlquist

FIU Electronic Theses and Dissertations

Climate change in the Arctic is predicted to increase plant productivity through decomposition-related enhanced nutrient availability. However, the extent of the increase will depend on whether the increased nutrient availability can be sustained. To address this uncertainty, I assessed the response of plant tissue nutrients, litter decomposition rates, and soil nutrient availability to experimental climate warming manipulations, extended growing season and soil warming, over a 7 year period. Overall, the most consistent effect was the year-to-year variability in measured parameters, probably a result of large differences in weather and time of snowmelt. The results of this study emphasize that although …


Skeletal Myosin Heavy Chain Function In Cultured Lung Myofibroblasts, Nancy A. Rice, Leslie A. Leinwand Oct 2003

Skeletal Myosin Heavy Chain Function In Cultured Lung Myofibroblasts, Nancy A. Rice, Leslie A. Leinwand

Biology Faculty Publications

Myofibroblasts are unique contractile cells with both muscle and nonmuscle properties. Typically myofibroblasts are identified by the expression of smooth muscle actin (ASMA); however some myofibroblasts also express sarcomeric proteins. In this study, we show that pulmonary myofibroblasts express three of the eight known sarcomeric myosin heavy chains (MyHCs) (IIa, IId, and embryonic) and that skeletal muscle myosin enzymatic activity is required for pulmonary myofibroblast contractility. Furthermore, inhibition of skeletal myosin activity and myofibroblast contraction results in a decrease in both ASMA and skeletal MyHC promoter activity and ASMA protein expression, suggesting a potential coupling of skeletal myosin activity and …