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The Identification Of Rana Ocellata Linnaeus, 1758. Nomenclatural Impact On The Species Currently Known As Leptodactylus Ocellatus (Leptodactylidae) And Osteopilus Brunneus (Gosse, 1851) (Hylidae), Esteban O. Lavilla, José A. Langone, Ulisses Caramaschi, W. Ronald Heyer, Rafael O. De Sá Jan 2010

The Identification Of Rana Ocellata Linnaeus, 1758. Nomenclatural Impact On The Species Currently Known As Leptodactylus Ocellatus (Leptodactylidae) And Osteopilus Brunneus (Gosse, 1851) (Hylidae), Esteban O. Lavilla, José A. Langone, Ulisses Caramaschi, W. Ronald Heyer, Rafael O. De Sá

Biology Faculty Publications

The usage of the name Rana ocellata Linnaeus, 1758, is plagued by misidentifications and misinterpretations. After an exhaustive bibliographic review, we conclude that the Linnaeus 1758 name refers to Osteopilus brunneus (Gosse, 1851) from Jamaica, while the taxon currently known as Leptodactylus ocellatus corresponds to Rana latrans Steffen, 1815. Herein, we designate and provide descriptions of the neotypes of Leptodactylus latrans (Steffen, 1815), revalidated, new combination, and Osteopilus ocellatus (Linnaeus, 1758), new combination, as a senior synonym of Osteopilus brunneus (Gosse, 1851).

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The Role Of Litter Quality Feedbacks In Terrestrial Nitrogen And Phosphorus Cycling, Johannes M.H. Knops, David A. Wedin, Shahid Naeem Jan 2010

The Role Of Litter Quality Feedbacks In Terrestrial Nitrogen And Phosphorus Cycling, Johannes M.H. Knops, David A. Wedin, Shahid Naeem

School of Biological Sciences: Faculty Publications

Many studies in ecosystem ecology argue for strong control of litter quality over nitrogen (N) cycling. We developed a model for temperate grasslands to test the importance of litter quality in decomposition for N and phosphorus (P) cycling based on the following premises. First, terrestrial N and P cycling differ fundamentally because N is a structural component of the soil organic matter (SOM), whereas P is not. Secondly, SOM has a much lower C:N ratio than litter inputs. Thirdly, litter decomposition follows an exponential decay with 20% of the original litter mass turning into SOM. Fourth, litter N concentration shows …

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Systemic Administration Of Antiretrovirals Prior To Exposure Prevents Rectal And Intravenous Hiv-1 Transmission In Humanized Blt Mice, Paul W. Denton, John F. Krisko, Daniel A. Powell, Melissa Mathias, Youn Tae Kwak, Francisco Martinez-Torres, Wei Zou, Deborah A. Payne, Jacob D. Estes, J. Victor Garcia Jan 2010

Systemic Administration Of Antiretrovirals Prior To Exposure Prevents Rectal And Intravenous Hiv-1 Transmission In Humanized Blt Mice, Paul W. Denton, John F. Krisko, Daniel A. Powell, Melissa Mathias, Youn Tae Kwak, Francisco Martinez-Torres, Wei Zou, Deborah A. Payne, Jacob D. Estes, J. Victor Garcia

Biology Faculty Publications

Successful antiretroviral pre-exposure prophylaxis (PrEP) for mucosal and intravenous HIV-1 transmission could reduce new infections among targeted high-risk populations including discordant couples, injection drug users, high-risk women and men who have sex with men. Targeted antiretroviral PrEP could be particularly effective at slowing the spread of HIV-1 if a single antiretroviral combination were found to be broadly protective across multiple routes of transmission. Therefore, we designed our in vivo preclinical study to systematically investigate whether rectal and intravenous HIV-1 transmission can be blocked by antiretrovirals administered systemically prior to HIV-1 exposure. We performed these studies using a highly relevant in …

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Expression Profiles During Dedifferentiation In Newt Lens Regeneration Revealed By Expressed Sequence Tags, Nobuyasu Maki, John Martinsou, Osamu Nishimura, Hiroshi Tarui, Jaroslaw Meller, Panagiotis A. Tsonis, Kiyokazu Agata Jan 2010

Expression Profiles During Dedifferentiation In Newt Lens Regeneration Revealed By Expressed Sequence Tags, Nobuyasu Maki, John Martinsou, Osamu Nishimura, Hiroshi Tarui, Jaroslaw Meller, Panagiotis A. Tsonis, Kiyokazu Agata

Biology Faculty Publications

Purpose: The adult newt can regenerate lens from pigmented epithelial cells (PECs) of the dorsal iris via dedifferentiation. The purpose of this research is to obtain sequence resources for a newt lens regeneration study and to obtain insights of dedifferentiation at the molecular level.

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Layered Organization In The Coastal Ocean: An Introduction To Planktonic Thin Layers And The Loco Project, James M. Sullivan, D. Van Holliday, Malcolm Mcfarland, Margaret A. Mcmanus, Olivia M. Cheriton, Kelly J. Benoit-Bird, Louis Goodman, Zhankun Wang, John P. Ryan, Mark Stacey, Charles Greenlaw, Mark A. Moline Jan 2010

Layered Organization In The Coastal Ocean: An Introduction To Planktonic Thin Layers And The Loco Project, James M. Sullivan, D. Van Holliday, Malcolm Mcfarland, Margaret A. Mcmanus, Olivia M. Cheriton, Kelly J. Benoit-Bird, Louis Goodman, Zhankun Wang, John P. Ryan, Mark Stacey, Charles Greenlaw, Mark A. Moline

Biological Sciences

No abstract provided.

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Integrated Measurements Of Acoustical And Optical Thin Layers Ii: Horizontal Length Scales, Mark A. Moline, Kelly J. Benoit-Bird, Ian C. Robbins, Maddie Schroth-Miller, Chad M. Waluk, Brian Zelenke Jan 2010

Integrated Measurements Of Acoustical And Optical Thin Layers Ii: Horizontal Length Scales, Mark A. Moline, Kelly J. Benoit-Bird, Ian C. Robbins, Maddie Schroth-Miller, Chad M. Waluk, Brian Zelenke

Biological Sciences

The degree of layered organization of planktonic organisms in coastal systems impacts trophic interactions, the vertical availability of nutrients, and many biological rate processes. While there is reasonable characterization of the vertical structure of these phenomena, the extent and horizontal length scale of variation has rarely been addressed. Here we extend the examination of the vertical scale in the first paper of the series to the horizontal scale with combined shipboard acoustic measurements and bio-optic measurements taken on an autonomous underwater vehicle. Measurements were made in Monterey Bay, CA from 2002 to 2008 for the bio-optical parameters and during 2006 …

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Integrated Measurements Of Acoustical And Optical Thin Layers I: Vertical Scales Of Association, Kelly J. Benoit-Bird, Mark A. Moline, Chad M. Waluk, Ian C. Robbins Jan 2010

Integrated Measurements Of Acoustical And Optical Thin Layers I: Vertical Scales Of Association, Kelly J. Benoit-Bird, Mark A. Moline, Chad M. Waluk, Ian C. Robbins

Biological Sciences

This study combined measurements from multiple platforms with acoustic instruments on moorings and on a ship and optics on a profiler and an autonomous underwater vehicle (AUV) to examine the relationships between fluorescent, bioluminescent, and acoustically scattering layers in Monterey Bay during nighttime hours in July and August of 2006 and May of 2008. We identified thin bioluminescent layers that were strongly correlated with acoustic scattering at the same depth but were part of vertically broad acoustic features, suggesting layers of unique composition inside larger biomass features. These compositional thin layers nested inside larger biomass features may be a common …

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Effects Of Small Increases In Corticosterone Levels On Morphology, Immune Function, And Feather Development, Michael W. Butler, Lynda L. Leppert, Alfred M. Dufty Jr. Jan 2010

Effects Of Small Increases In Corticosterone Levels On Morphology, Immune Function, And Feather Development, Michael W. Butler, Lynda L. Leppert, Alfred M. Dufty Jr.

Biology Faculty Publications and Presentations

Stressors encountered during avian development may affect an individual’s phenotype, including immunocompetence, growth, and feather quality. We examined effects of simulated chronic low-level stress on American kestrel (Falco sparverius) nestlings. Continuous release of corticosterone, a hormone involved in the stress response, can model chronic stress in birds. We implanted 13-d-old males with either corticosterone-filled implants or shams and measured their growth, immune function, and feather coloration.We found no significant differences between groups at the end of the weeklong exposure period in morphometrics (mass, tarsus, wing length, and asymmetry), immunocompetence (cutaneous immunity, heterophil/lymphocyte ratio, and humoral immunity), or feather …

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A Search For Genetic Modifiers Responsible For Congenital Heart Disease Variability In The Presence Of Nkx2-5 Haploinsufficiency, Julia Brandeis Winston Honold Jan 2010

A Search For Genetic Modifiers Responsible For Congenital Heart Disease Variability In The Presence Of Nkx2-5 Haploinsufficiency, Julia Brandeis Winston Honold

All Theses and Dissertations (ETDs)

While a clear heritable risk has been observed for congenital heart disease, there is considerable variation in penetrance and presentation likely due to multiple genetic and environmental risk factors. To identify causative factors and interactions responsible for variability in heart development, greater than 4,200 hearts from Nkx2-5 heterozygous knockout mice have been collected and examined. Nkx2-5+/- mice in the inbred strain background C57Bl/6 frequently have atrial and ventricular septal defects. The incidences are substantially reduced in the Nkx2-5+/- progeny of first-generation: F1) outcrosses to the strains FVB/N or A/J. Defects recur in the second generation: F2) of the F1xF1 intercross …

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Leptodactylus Cunicularius, W. R. Heyer, Miriam M. Heyer, Rafael O. De Sá Jan 2010

Leptodactylus Cunicularius, W. R. Heyer, Miriam M. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus cunicularius are moderately small. The head is longer than wide and the hind limbs are long (Table 1; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are internal, not externally expanded. The snout is protruding, not sexually dimorphic. Male forearms are not hypertrophied and males lack asperities on the thumbs and chest. The dorsum is variegated with small, often confluent, spots and blotches. There is a very thin interrupted mid-dorsal light stripe (pinstripe). Usually, there is a noticeable light, irregular, elongate, mid-dorsal blotch in the scapular region. The …

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Leptodactylus Syphax, W. R. Heyer, Miriam M. Heyer, Rafael O. De Sá Jan 2010

Leptodactylus Syphax, W. R. Heyer, Miriam M. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus syphax are moderately sized (males 58-83 mm, females 70-90 mm SVL). The head is about as long as wide, but usually is just wider than long. The hind limbs are moderately short (Table 1; Heyar and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are laterally expanded, tan, and not darker than the adjacent throat. The male snout is not spatulate, the snout profile is rounded to obtuse in both sexes. Male arms are hypertrophied during the breeding season in sexually active males. The male thumb has two large, …

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Genome Sequence Of The Palaeopolyploid Soybean, Jeremy Schmutz, Steven B. Cannon, Jessica Schlueter, Jianxin Ma, Therese Mitros, William Nelson, David L. Hyten, Qijian Song, Jay J. Thelen, Jianlin Cheng, Dong Xu, Uffe Hellsten, Gregory D. May, Yeisoo Yu, Tetsuya Sakurai, Taishi Umezawa, Madan K. Bhattacharyya, Devinder Sandhu, Babu Valliyodan, Erika Lindquist, Myron Peto, David Grant, Shengqiang Shu, David Goodstein, Kerrie Barry, Montona Futrell-Griggs, Brian Abernathy, Jianchang Du, Zhixi Tian, Liucun Zhu, Navdeep Gill, Trupti Joshi, Marc Libault, Anand Sethuraman, Xue-Cheng Zhang, Kazuo Shinozaki, Henry T. Nguyen, Rod A. Wing, Perry Cregan, James Specht, Jane Grimwood, Dan Rokhsar, Gary Stacey, Randy C. Shoemaker, Scott A. Jackson Jan 2010

Genome Sequence Of The Palaeopolyploid Soybean, Jeremy Schmutz, Steven B. Cannon, Jessica Schlueter, Jianxin Ma, Therese Mitros, William Nelson, David L. Hyten, Qijian Song, Jay J. Thelen, Jianlin Cheng, Dong Xu, Uffe Hellsten, Gregory D. May, Yeisoo Yu, Tetsuya Sakurai, Taishi Umezawa, Madan K. Bhattacharyya, Devinder Sandhu, Babu Valliyodan, Erika Lindquist, Myron Peto, David Grant, Shengqiang Shu, David Goodstein, Kerrie Barry, Montona Futrell-Griggs, Brian Abernathy, Jianchang Du, Zhixi Tian, Liucun Zhu, Navdeep Gill, Trupti Joshi, Marc Libault, Anand Sethuraman, Xue-Cheng Zhang, Kazuo Shinozaki, Henry T. Nguyen, Rod A. Wing, Perry Cregan, James Specht, Jane Grimwood, Dan Rokhsar, Gary Stacey, Randy C. Shoemaker, Scott A. Jackson

Biology Faculty Articles

Soybean (Glycine max) is one of the most important crop plants for seed protein and oil content, and for its capacity to fix atmospheric nitrogen through symbioses with soil-borne microorganisms. We sequenced the 1.1-gigabase genome by a whole-genome shotgun approach and integrated it with physical and high-density genetic maps to create a chromosome-scale draft sequence assembly. We predict 46,430 protein-coding genes, 70% more than Arabidopsis and similar to the poplar genome which, like soybean, is an ancient polyploid (palaeopolyploid). About 78% of the predicted genes occur in chromosome ends, which comprise less than one-half of the genome but …

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Investigating The Activity Spectrum For Ring-Substituted 8-Hydroxyquinolines, James Carroll, Jim O'Mahony, Aidan Coffey, Et. Al. Jan 2010

Investigating The Activity Spectrum For Ring-Substituted 8-Hydroxyquinolines, James Carroll, Jim O'Mahony, Aidan Coffey, Et. Al.

Department of Biological Sciences Publications

In this study, a series of fourteen ring-substituted 8-hydroxyquinoline derivatives were prepared. The synthesis procedures are presented. The compounds were analyzed using RP-HPLC to determine lipophilicity. They were tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. Primary in vitro screening of the synthesized compounds was also performed against four mycobacterial strains and against eight fungal strains. Several compounds showed biological activity comparable with or higher than the standards isoniazid or fluconazole. For all the compounds, the relationships between the lipophilicity and the chemical structure of the studied compounds are discussed.

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Domestic Exotics And The Perception Of Invasibility, Qinfeng Guo, Robert Ricklefs Jan 2010

Domestic Exotics And The Perception Of Invasibility, Qinfeng Guo, Robert Ricklefs

Biology Department Faculty Works

Susceptibility of an area to invasion by exotic species is often judged by the fraction of introduced species in the local biota. However, the degree of invasion, particularly in mainland areas, has often been underestimated because of the exclusion of ‘domestic exotics’ (those introduced to internal units from within the national border) in calculations. Because all introduced species on islands are considered as exotics, this contributes to the perception that islands are more susceptible to invasion than are continental regions. Here, we determine the contribution of domestic exotic species to the degree of invasion (exotic fraction) in mainland areas. We …

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Impacts Of An Orange Oil Solvent And Stickem On The Detection Of Xylella Fastidiosa Dna In Glassy-Winged Sharpshooters, Homalodisca Vitripennis (Hemiptera: Cicadellidae), Patrick Marshall, Daymon Hail, Forrest Mitchell, Blake Bextine Jan 2010

Impacts Of An Orange Oil Solvent And Stickem On The Detection Of Xylella Fastidiosa Dna In Glassy-Winged Sharpshooters, Homalodisca Vitripennis (Hemiptera: Cicadellidae), Patrick Marshall, Daymon Hail, Forrest Mitchell, Blake Bextine

Biology Faculty Publications and Presentations

Xylella fastidiosa is a plant pathogenic bacterium that causes many economically important agricultural diseases and is transmitted by the glassy-winged sharpshooter, Homalodisca vitripennis (Hemiptera: Cicadellidae). Efficient detection of X. fastidiosa in field collected H. vitripennis in an area-wide management program can contribute to risk assessment associated with insect presence in vineyards. Prior to conducting molecular assays for detection of X. fastidiosa in individual insects, H. vitripennis must be removed from yellow sticky traps with a solvent such as orange oil. In this study, we determined the effect of orange oil concentration on extraction of individual H. vitripennis following trap removal …

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Tuning A Nose To Forage: Evidence For Olfactory Learning In A Procellariiform Seabird Chicks, Gregory B. Cunningham, Gabrielle A. Nevitt Jan 2010

Tuning A Nose To Forage: Evidence For Olfactory Learning In A Procellariiform Seabird Chicks, Gregory B. Cunningham, Gabrielle A. Nevitt

Biology Faculty/Staff Publications

Burrow nesting procellariiform seabirds use olfactory cues for both foraging and nest recognition. As chicks, burrow nesters develop in the dark, but are exposed to both prey-related and individual-specific scents through contact with their parents. This exposure suggests that chicks may have the opportunity to learn odours while still in the nest. In this study, we examined whether exposure to odourants during development might influence olfactory search behaviour expressed later in life. To test this idea, we exposed eggs of thin-billed prions Pachyptila belcheri to a rosy-scented novel odour (phenyl ethyl alcohol, PEA) or a control (water) just before hatching; …

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Insights From Comparative Analyses Of Aging In Birds And Mammals, Robert Ricklefs Jan 2010

Insights From Comparative Analyses Of Aging In Birds And Mammals, Robert Ricklefs

Biology Department Faculty Works

Many laboratory models used in aging research are inappropriate for understanding senescence in mammals, including humans, because of fundamental differences in life history, maintenance in artificial environments, and selection for early aging and high reproductive rate. Comparative studies of senescence in birds and mammals reveal a broad range in rates of aging among a variety of taxa with similar physiology and patterns of development. These comparisons suggest that senescence is a shared property of all vertebrates with determinate growth, that the rate of senescence has been modified by evolution in response to the potential life span allowed by extrinsic mortality …

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Genome Sequence Of The Pea Aphid Acyrthosiphon Pisum, The International Aphid Genomics Consortium Jan 2010

Genome Sequence Of The Pea Aphid Acyrthosiphon Pisum, The International Aphid Genomics Consortium

Biology Articles and Papers

Aphids are important agricultural pests and also biological models for studies of insect-plant interactions, symbiosis, virus vectoring, and the developmental causes of extreme phenotypic plasticity. Here we present the 464 Mb draft genome assembly of the pea aphid Acyrthosiphon pisum. This first published whole genome sequence of a basal hemimetabolous insect provides an outgroup to the multiple published genomes of holometabolous insects. Pea aphids are host-plant specialists, they can reproduce both sexually and asexually, and they have coevolved with an obligate bacterial symbiont. Here we highlight findings from whole genome analysis that may be related to these unusual biological features. …

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A Habitat Model For The Detection Of Two-Lined Salamanders At C. F. Phelps Wildlife Management Area, Fauquier And Culpeper Counties, Virginia, Jay Mcghee, Michael D. Killian Jan 2010

A Habitat Model For The Detection Of Two-Lined Salamanders At C. F. Phelps Wildlife Management Area, Fauquier And Culpeper Counties, Virginia, Jay Mcghee, Michael D. Killian

Virginia Journal of Science

Aquatic salamanders represent an important component of Virginia river watersheds, but despite potential declines, few specifics are known about their habitat preferences. We surveyed the habitats of the northern two-lined salamander and collected data on an array of habitat variables associated with the species. We used a logistic regression analysis to develop a model predicting its presence or absence for a given 50m-transect. Our final model incorporated the variation in stream depth and direction of stream flow and accounted for 25% of the variation in our data. We conclude that stream depth variation is an important feature of salamander habitat …

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Functional Feeding Groups, Species Richness, And Spatial Distributions Of Fishes In Rocky And Sandy Beach Habitats Of St. John, U.S. Virgin Islands, Eugene G. Maurakis, George E. Maurakis, Demetri E. Maurakis Jan 2010

Functional Feeding Groups, Species Richness, And Spatial Distributions Of Fishes In Rocky And Sandy Beach Habitats Of St. John, U.S. Virgin Islands, Eugene G. Maurakis, George E. Maurakis, Demetri E. Maurakis

Virginia Journal of Science

Objectives were to identify and compare fish species richness, functional feeding group richness and diversity, and delineate distributions of fishes at rocky and sandy beach habitats at St. John, U.S. Virgin Islands. Visual observations using snorkel and mask were made at 3-m intervals seaward from shore during daylight hours. A total of 69 taxa (67 species) representing 33 families of fishes were observed. Total (53) and average fish species richness (32.7) at rocky beach habitats were greater than those (total=43; average=24.3) at sandy beach habitats. Twelve functional feeding groups were identified (diurnal planktivores, excavators/eroders, macroalgae browsers, macrocarnivores, mobile benthic scrapers, …

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Ecological Opportunity And The Origin Of Adaptive Radiations, J. B. Yoder, E. Clancey, S. Des Roches, J. M. Eastman, L. Gentry, W. Godsoe, T. J. Hagey, D. Jochimsen, B. P. Oswald, J. Robertson, B. Sarver, J. J. Schenk, S. F. Spear, L. J. Harmon Jan 2010

Ecological Opportunity And The Origin Of Adaptive Radiations, J. B. Yoder, E. Clancey, S. Des Roches, J. M. Eastman, L. Gentry, W. Godsoe, T. J. Hagey, D. Jochimsen, B. P. Oswald, J. Robertson, B. Sarver, J. J. Schenk, S. F. Spear, L. J. Harmon

Biology

Ecological opportunity – through entry into a new environment, the origin of a key innovation or extinction of antagonists – is widely thought to link ecological population dynamics to evolutionary diversification. The population-level processes arising from ecological opportunity are well documented under the concept of ecological release. However, there is little consensus as to how these processes promote phenotypic diversification, rapid speciation and adaptive radiation. We propose that ecological opportunity could promote adaptive radiation by generating specific changes to the selective regimes acting on natural populations, both by relaxing effective stabilizing selection and by creating conditions that ultimately generate diversifying …

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Thermal Preferences And Distribution Of Northern Michigan Crayfishes, Troy Keller Jan 2010

Thermal Preferences And Distribution Of Northern Michigan Crayfishes, Troy Keller

Faculty Bibliography

Crayfishes function as both ecosystem engineers and keystone species, and they serve as the trophic linkage between benthic organisms and fish predators. Because crayfish behavior, physiology, and growth are controlled by temperature, thermal differences among habitats may have important implications for crayfishes and the ecosystems they inhabit. To investigate the association between crayfish and temperature, we measured thermal preferences of 3 crayfish species in lab experiments (2007), recorded summer water temperatures at 9 sites (July 1-August 9, 2008), and trapped crayfishes at these same sites in northern Michigan. Orconectes rusticus (non-indigenous) preferred nearly 1 °C warmer water (=22 °C) than …

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Evidence For Decline In The Unionidae Of The East Branch Rocky River, Ohio, Daniel A. Gouch, Mark S. Lyons, Robert A. Krebs Jan 2010

Evidence For Decline In The Unionidae Of The East Branch Rocky River, Ohio, Daniel A. Gouch, Mark S. Lyons, Robert A. Krebs

Biological, Geological, and Environmental Faculty Publications

A survey of freshwater mussels (Mollusca: Bivalvia: Unionidae) was conducted for the East Branch Rocky River, Ohio, during the summer of 2006. Development in this watershed is moderate though rapidly expanding, particularly in the upstream reaches. Perhaps as a consequence, a preliminary search failed to reveal any live mussels in the river in 2003 . The present report is of an extensive survey covering 21 two-hour timed searches for live mussels and shells combined with visual assessments of disturbance and tests for water quality at each site. All searches were visual or by feeling for mussels embedded in the stream …

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A Newly Discovered Role Of Telomeres In An Ancient Organism, Bibo Li Jan 2010

A Newly Discovered Role Of Telomeres In An Ancient Organism, Bibo Li

Biological, Geological, and Environmental Faculty Publications

Trypanosoma brucei expresses Variant Surface Glycoprotein (VSG) genes in a strictly monoallelic fashion in its mammalian hosts, and the regulation of this important virulence mechanism has been the research focus for decades. Telomere position effect (TPE), an epigenetic phenomenon, has been proposed to play a critical role in VSG regulation, yet no telomeric protein was identified whose disruption led to VSG derepression. We recently identified tbRAP1 as an intrinsic component of the T. brucei telomere complex and a major regulator for silencing VSG expression sites (ESs). Knockdown of tbRAP1 led to derepression of all ES-linked VSGs but not VSGs located …

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The Role Of Chmp1 In Drosophila Melanogaster, Meagan E. Valentine Jan 2010

The Role Of Chmp1 In Drosophila Melanogaster, Meagan E. Valentine

Theses, Dissertations and Capstones

Chmp1A has recently been linked to pancreatic cancer, a leading cause of cancer death in humans. Pancreatic tumors have lowered Chmp1A expression, and it has been described as a tumor suppressor. Chmp1A is also a member of ESCRT III (Endosomal Sorting Complex Required for Transport), a conserved protein complex involved in the degradation and recycling of activated transmembrane receptors. There is a single Chmp1 protein in Drosophila that is homologous to vertebrate Chmp1A; however, Chmp1 hasn’t been studied in Drosophila. The objective of this study was to characterize Chmp1 in Drosophila using gene knockdown and over-expression. We used an …

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Methane Emission From A Tropical Wetland In Ka'au Crater, O'Ahu, Hawai'i, Maxime Grand, Eric Gaidos Jan 2010

Methane Emission From A Tropical Wetland In Ka'au Crater, O'Ahu, Hawai'i, Maxime Grand, Eric Gaidos

Faculty Publications

Natural tropical wetlands constitute an important but still poorly studied source of atmospheric methane, a powerful greenhouse gas. We measured net methane emission, soil profiles of methane generation and oxidation, and related environmental parameters in a tropical wetland occupying the Ka'au extinct volcanic crater on the Hawaiian island of O'ahu. The wetland has a fluctuating water table with dynamics that can be reproduced using precipitation data and a simple model. Median net methane flux was 117 mg m-2 day-1 and is consistent with measurements at other tropical sites. Net methane flux in the Commelina diffusa—dominated vegetation pattern (honohono) was significantly …

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An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias Jan 2010

An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias

WM Keck Science Faculty Papers

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation. …

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A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg Jan 2010

A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg

WM Keck Science Faculty Papers

The ‘breccia’ stratum from Kents (we follow local tradition in using the form ‘Kents’, without an apostrophe) Cavern, England, has been well known for its rich yield of cave-bear material since excavations began in the mid-19th century. Recent work has established that the bears are of latest MIS 12 or earliest MIS 11 age. A life table based on a collection of 67 molariform teeth is consistent with the use of the cave as a hibernaculum. Univariate and morphological assessment of the teeth shows an unusual range of primitive and more derived characters. Multivariate morphometric analysis of cave-bear teeth from …

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Fecal Indicator Bacteria Concentrations In Furman Lake And Its Feeder Streams, Philip Hearn, T.J. Melton, Emily Tripp, Victoria Grimm-Oropesa Jan 2010

Fecal Indicator Bacteria Concentrations In Furman Lake And Its Feeder Streams, Philip Hearn, T.J. Melton, Emily Tripp, Victoria Grimm-Oropesa

Furman Lake Restoration Book Gallery

A three page summary by four Furman students describing their research on fecal indicator bacteria in the Furman Lake and streams. The summary contains a map and bar charts.

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Differences In Antibiotic Resistance In Fresh-Water Bacteria From Furman Lake And Feeder Streams, Dylan Richards, Clarissa Graham, Laura Snyder Jan 2010

Differences In Antibiotic Resistance In Fresh-Water Bacteria From Furman Lake And Feeder Streams, Dylan Richards, Clarissa Graham, Laura Snyder

Furman Lake Restoration Book Gallery

A one page summary by three Furman students describing their research on bacteria found in the Furman Lake.

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