Life Sciences Commons^™

Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice

Biology Faculty Publications

The timing and pattern of myogensis varies among anurans that have been studied and the different patterns may provide useful phylogenetic information. Specific myogenic markers have been described (Muntz, 1975; Kielbowna, 1981; Boudjelida & Muntz, 1987; Radice et al., l989) and they can provide information on evolutionary changes for closely related lineages within a clade. For example, we previously compared first appearance of a muscle-specific protein, first twitch of axial muscle, onset of multinucleation within axial myotome, and first heartbeat in two pipid genera (Smetanick, et al., 1999). We found that although the timing of myogensis differed, the sequence of …

Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice

Biology Faculty Publications

The timing and pattern of myogenesis varies among anurans that have been studied and the different pat- terns may provide useful phylogenetic information. Specific myogenic markers have been described (Muntz, 1975; Kielbowna, 1981; Boudjelida & Muntz, 1987; Radice et al., 1989) and they can provide infor- mation on evolutionary changes for closely related lineages within a clade. For example, we previously com- pared first appearance of a muscle-specific protein, first twitch of axial muscle, onset of multinucleation within axial myotome, and first heartbeat in two pipid genera (Smetanick et al., 1999). We found that although the timing of myogenesis differed, …

Biomechanics And Energetics In Aquatic And Semiaquatic Mammals: Platypus To Whale, Frank E. Fish

Biology Faculty Publications

A variety of mammalian lineages have secondarily invaded the water. To locomote and thermoregulate in the aqueous medium, mammals developed a range of morphological, physiological, and behavioral adaptations. A distinct difference in the suite of adaptations, which affects energetics, is apparent between semiaquatic and fully aquatic mammals. Semiaquatic mammals swim by paddling, which is inefficient compared to the use of oscillating hydrofoils of aquatic mammals. Semiaquatic mammals swim at the water surface and experience a greater resistive force augmented by wave drag than submerged aquatic mammals. A dense, nonwettable fur insulates semiaquatic mammals, whereas aquatic mammals use a layer of …

Parental Care In Sphaerium Striatinum Lamarck: Evidence For Retention Of Competent Offspring, Mark Beekey, Ronald H. Karlson, Alyse R. Greenberg

Biology Faculty Publications

The timing of offspring release is a fundamental turning point in the life history of any organism. It represents the end to many of the most costly forms of parental care (e.g., provisioning of nutrients for developing eggs and zygotes) and the beginning of an independent life for the offspring. Generally temporal variation in this event is attributed to a variety of physiological and evolutionary trade-offs. Here we examine the retention of offspring in the freshwater clam Sphaerium striatinum Lamarck. Brooded offspring are typically not released into the environment until they are 4.0 mm shell length (SL). We provide evidence …

Los Anfibios Del Monumento Natural Barro Colorado, Parque Nacional Soberania Y Areas Adyacentes, Rafael O. De Sá

Biology Faculty Publications

This book focuses on the batrachofauna of Barro Colorado Nature Monument. Soberania National Park and adjacent areas. It complements other recent publications on Neotropical amphibians such as those by Rodriguez and Duellman ( 1994) on Peru, Achaval and Olmos (1995) on Uruguay, and Meyer and Foster (1996) on Belize. The goal of these books is to reach a wider audience than the more technical batrachofaunal summaries-e.g., Frogs of Boracéia (Heyer 1990). Amphibians of Argentina (Cei 1985), and Frogs of the Genus Eleutherodactylus in Western Ecuador (Lynch and Duellman 1997). These geographically focused guides are especially useful to students, amateur biologists, …

The Occurrence Of The Freshwater Clams, Musculium Partumeium (Say) And Pisidium Casertanum (Poli) (Bivalvia: Sphaeriidae), In The Hawaiian Islands, Albert J. Burky, Carl M. Way, Skippy Hau, M. Eric Benbow

Biology Faculty Publications

Sphaeriid clams were collected from an ancient, continuously cultivated taro pond complex at Ke‘anae Peninsula, Maui. Both species are known for adaptations for temporary pond habitats and could have been initially introduced by the earliest Hawaiian settlers transported with moist taro root stock from other areas of Oceania.

Intracellular Transport, Assembly, And Degradation Of Wild-Type And Disease-Linked Mutant Gap Junction Proteins, Judy K. Vanslyke, Suzanne M. Deschênes, Linda S. Musil

Biology Faculty Publications

More than 130 different mutations in the gap junction integral plasma membrane protein connexin32 (Cx32) have been linked to the human peripheral neuropathy X-linked Charcot–Marie–Tooth disease (CMTX). How these various mutants are processed by the cell and the mechanism(s) by which they cause CMTX are unknown. To address these issues, we have studied the intracellular transport, assembly, and degradation of three CMTX-linked Cx32 mutants stably expressed in PC12 cells. Each mutant had a distinct fate: E208K Cx32 appeared to be retained in the endoplasmic reticulum (ER), whereas both the E186K and R142W mutants were transported to perinuclear compartments from which …

Identification Of Fungal Pathogens Of Grasshoppers, M. J. Bidochka, Donald W. Roberts

Biology Faculty Publications

No abstract provided.

Abnormal Pigmentation In A Franklin's Gull, Philip C. Chu

Biology Faculty Publications

No abstract provided.

Los Coquís De Puerto Rico: Su Historia Natural Y Conservación, Rafael O. De Sá

Biology Faculty Publications

As the title indicates, this well-illustrated (115 photographs and 76 illustrations) book summarizes the current knowledge about the natural history of the 16 species of Eleutherodactylus inhabiting Puerto Rico. The book consists of eight chapters (including the epilogue) and it is clearly stated that it was written to serve both the scientific community and the nonspecialist reader. The goal of bridging these two audiences is ambitious and usually difficult; however, the book has probably accomplished this goal. The technical reader, i.e., students and professional herpetologists, will find a good summary of data and enough information to continue reading with interest. …

A Summer Survey Of The Birds At Two Eastern Nebraska Wetlands, Kristine T. Phipps

Biology Faculty Publications

This study compares the avian species diversity at two eastern Nebraska wetlands that differ in their relative isolation from an urban environment. Birds were surveyed by the point Count method twice weekly at each site during June of 1998. Diversity was measured using species richness and species evenness. The percentage of bird species observed that depend on wetlands for breeding was also compared. Results suggest that both species richness and evenness, as determined by the Shannon-Wiener index, were higher at the wetland located in a network of other marsh areas and agricultural land than at the suburban wetland. Immigration of …

Discovering Teamwork - A Novel Cooperative Learning Activity To Encourage Group Interdependence, Maureen T. Knabb

Biology Faculty Publications

No abstract provided.

Eph Receptors And Ephrins, Masaru Nakamoto

Biology Faculty Publications

The Eph receptors are the largest known family of receptor tyrosine kinases. The Eph receptors and theirmembrane-attached ligands, ephrins, show diverse expression patterns during development. Recent studies havedemonstrated that Eph receptors and ephrins play important roles in many developmental processes, includingneuronal network formation, the patterning of the neural tube and the paraxial mesoderm, the guidance of cellmigration, and vascular formation. In the nervous system, Eph receptors and ephrins have been shown to act aspositional labels to establish topographic projections. They also play a key role in pathway ®nding by axons andneural crest cells. The crucial roles of Eph receptors and …

Direct And Indirect Effects Of Herbivores On Nitrogen Dynamics: Voles In Riparian Areas, J M. Sirotnak, Nancy J. Huntly

Biology Faculty Publications

Herbivores can directly increase nitrogen mobility by increasing the quality of organic matter entering the decomposition cycle, but they also may decrease nitrogen mobility by decreasing the biomass of high-nitrogen species in the plant community. We assessed effects of voles (Microtus) on nitrogen dynamics using exclosures in two riparian meadows (Crystal Bench and Blacktail Deer Creek) in Yellowstone National Park (USA). At both sites, the quantity of plant litter was decreased by herbivory following a vole population peak in 1992. At Crystal Bench, removal of voles caused a decrease in the nitrogen concentration and an increase in the C:N ratio …

Incomplete Cd8 + T Lymphocyte Differentiation As A Mechanism For Subdominant Cytotoxic T Lymphocyte Responses To A Viral Antigen, Juliet V. Spencer, Thomas J. Braciale

Biology Faculty Publications

CD8⁺ cytotoxic T lymphocytes (CTLs) recognize antigen in the context of major histocompatibility complex (MHC) class I molecules. Class I epitopes have been classified as dominant or subdominant depending on the magnitude of the CTL response to the epitope. In this report, we have examined the in vitro memory CTL response of H-2^d haplotype murine CD8⁺ T lymphocytes specific for a dominant and subdominant epitope of influenza hemagglutinin using activation marker expression and staining with soluble tetrameric MHC–peptide complexes. Immune CD8⁺ T lymphocytes specific for the dominant HA204-210 epitope give rise to CTL effectors that display …

Energy Metabolism In Uncoupling Protein 3 Gene Knockout Mice, A. Vidal-Puig, D. Grujic, C. Zhang, T. Hagen, O. Boss, Y. Ido, A. Szczepanik, Jennifer Wade, V. Mootha, R. Cortright, D. M. Muoio, B. B. Lowell

Biology Faculty Publications

Uncoupling protein 3 (UCP3) is a member of the mitochondrial anion carrier superfamily. Based upon its high homology with UCP1 and its restricted tissue distribution to skeletal muscle and brown adipose tissue, UCP3 has been suggested to play important roles in regulating energy expenditure, body weight, and thermoregulation. Other postulated roles for UCP3 include regulation of fatty acid metabolism, adaptive responses to acute exercise and starvation, and prevention of reactive oxygen species (ROS) formation. To address these questions, we have generated mice lacking UCP3 (UCP3 knockout (KO) mice). Here, we provide evidence that skeletal muscle mitochondria lacking UCP3 are more …

Expression Of Human Α2-Adrenergic Receptors In Adipose Tissue Of Β3-Adrenergic Receptor-Deficient Mice Promotes Diet-Induced Obesity, P. Valet, D. Grujic, Jennifer Wade, M. Ito, M. C. Zingaretti, V. Soloveva, S. R. Ross, R. A. Graves, S. Cinti, M. Lafontan, B. B. Lowell

Biology Faculty Publications

Catecholamines play an important role in controlling white adipose tissue function and development. β- and α2-adrenergic receptors (ARs) couple positively and negatively, respectively, to adenylyl cyclase and are co-expressed in human adipocytes. Previous studies have demonstrated increased adipocyte α2/β-AR balance in obesity, and it has been proposed that increased α2-ARs in adipose tissue with or without decreased β-ARs may contribute mechanistically to the development of increased fat mass. To critically test this hypothesis, adipocyte α2/β-AR balance was genetically manipulated in mice. Human α2A-ARs were transgenically expressed in the adipose tissue of mice that were either homozygous (−/−) or heterozygous (+/−) …

Organic Carbon Supply And Metabolism In A Near-Stream Groundwater Ecosystem, H. M. Valett, C. C. Dahm, Michelle A. Baker

Biology Faculty Publications

In groundwater ecosystems, in situ primary production is low, and metabolism depends on organic matter inputs from other regions of the catchment. Heterotrophic metabolism and biogeochemistry in the floodplain groundwater of a headwater catchment (Rio Calaveras, New Mexico, USA) were examined to address the following questions: (1) How do groundwater metabolism and biogeochemistry vary spatially and temporally? (2) What factors influence groundwater metabolism? (3) What is the energy source for groundwater metabolism?

At Rio Calaveras, surface discharge and water table elevation increased at the onset of spring snowmelt. Groundwater biogeochemical changes in response to snowmelt included increases in dissolved oxygen …