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Biological Sciences Faculty Publications

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Articles 751 - 780 of 1571

Full-Text Articles in Life Sciences

Effects Of Curcumin On Stem-Like Cells In Human Esophageal Squamous Carcinoma Cell Lines, Michael Eric Geusz, Taghreed N. Almanaa, Roudabeh J. Jamasbi Jan 2012

Effects Of Curcumin On Stem-Like Cells In Human Esophageal Squamous Carcinoma Cell Lines, Michael Eric Geusz, Taghreed N. Almanaa, Roudabeh J. Jamasbi

Biological Sciences Faculty Publications

Background: Many cancers contain cell subpopulations that display characteristics of stem cells. Because these cancer stem cells (CSCs) appear to provide resistance to chemo-radiation therapy, development of therapeutic agents that target CSCs is essential. Curcumin is a phytochemical agent that is currently used in clinical trials to test its effectiveness against cancer. However, the effect of curcumin on CSCs is not well established. The current study evaluated curcumin-induced cell death in six cancer cell lines derived from human esophageal squamous cell carcinomas. Moreover, these cell lines and the ones established from cells that survived curcumin treatments were characterized.Methods: Cell loss …

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An At Mutational Bias In The Tiny Gc-Rich Endosymbiont Genome Of Hodgkinia, James T. Van Leuven, John Mccutcheon Jan 2012

An At Mutational Bias In The Tiny Gc-Rich Endosymbiont Genome Of Hodgkinia, James T. Van Leuven, John Mccutcheon

Biological Sciences Faculty Publications

The fractional guanine + cytosine (GC) contents of sequenced bacterial genomes range from 13% to 75%. Despite several decades of research aimed at understanding this wide variation, the forces controlling GC content are not well understood. Recent work has suggested that a universal adenine + thymine (AT) mutational bias exists in all bacteria and that the elevated GC contents found in some bacterial genomes is due to genome-wide selection for increased GC content. These results are generally consistent with the low GC contents observed in most strict endosymbiotic bacterial genomes, where the loss of DNA repair mechanisms combined with the …

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A New Forest Fire Paradigm: The Need For High-Severity Fires, Monica L. Bond, Rodney B. Siegel, Richard L. Hutto, Victoria A. Saab, Stephen A. Shunk Jan 2012

A New Forest Fire Paradigm: The Need For High-Severity Fires, Monica L. Bond, Rodney B. Siegel, Richard L. Hutto, Victoria A. Saab, Stephen A. Shunk

Biological Sciences Faculty Publications

Forest fires, particularly those that burn at mixed and high severity (collectively called ‘severe’), have been traditionally perceived as catastrophic events, directing public attention and immense forest management budgets toward fire prevention and suppression. These fires may indeed be catastrophic when measured by losses of human lives and property. However, severe fires in wildland areas are both natural and necessary to maintain the integrity of dynamic, disturbance-adapted forest systems. We propose a change in the current paradigm—which holds that severe forest fires are always harmful—to a new one that embraces their ecological necessity.

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The Curious Case Of Arenavirus Entry, And Its Inhibition, Jack H. Nunberg, Joanne York Jan 2012

The Curious Case Of Arenavirus Entry, And Its Inhibition, Jack H. Nunberg, Joanne York

Biological Sciences Faculty Publications

Arenaviruses comprise a diverse family of enveloped negative-strand RNA viruses that are endemic to specific rodent hosts worldwide. Several arenaviruses cause severe hemorrhagic fevers in humans, including Junin and Machupo viruses in South America and Lassa fever virus in western Africa. Arenavirus entry into the host cell is mediated by the envelope glycoprotein complex, GPC. The virion is endocytosed on binding to a cell-surface receptor, and membrane fusion is initiated in response to physiological acidification of the endosome. As with other class I virus fusion proteins, GPC-mediated membrane fusion is promoted through a regulated sequence of conformational changes leading to …

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Correlation Of Air Displacement Plethysmography With Alternative Body Fat Measurement Techniques In Men And Women, Brittany L. Reinert, Roberta L. Pohlman, Lynn K. Hartzler Jan 2012

Correlation Of Air Displacement Plethysmography With Alternative Body Fat Measurement Techniques In Men And Women, Brittany L. Reinert, Roberta L. Pohlman, Lynn K. Hartzler

Biological Sciences Faculty Publications

Obesity has reached epidemic proportions with serious health consequences. Techniques used to measure body fat (BF) yield variable BF estimates, and this variability may lead to underestimation or overestimation of BF and subsequent treatment options. The measurements that are most accurate (Dual-Energy X-ray Absorptiometry (DEXA) and Air Displacement Plethysmography (ADP)) are expensive and often unavailable. The purpose of this study is to find the commonly available BF measurement that is the most accurate and practical for individual body types in the general population and compare these measurements to ADP (BOD POD®) as the standard. Field measurements include skinfolds …

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Prmt5 And The Role Of Symmetrical Dimethylarginine In Chromatoid Bodies Of Planarian Stem Cells, Labib Rouhana, Ana P. Vieira, Rachel H. Roberts-Galbraith, Phillip A. Newmark Jan 2012

Prmt5 And The Role Of Symmetrical Dimethylarginine In Chromatoid Bodies Of Planarian Stem Cells, Labib Rouhana, Ana P. Vieira, Rachel H. Roberts-Galbraith, Phillip A. Newmark

Biological Sciences Faculty Publications

Planarian flatworms contain a population of adult stem cells (neoblasts) that proliferate and generate cells of all tissues during growth, regeneration and tissue homeostasis. A characteristic feature of neoblasts is the presence of chromatoid bodies, large cytoplasmic ribonucleoprotein (RNP) granules morphologically similar to structures present in the germline of many organisms. This study aims to reveal the function, and identify additional components, of planarian chromatoid bodies. We uncover the presence of symmetrical dimethylarginine (sDMA) on chromatoid body components and identify the ortholog of protein arginine methyltransferase PRMT5 as the enzyme responsible for sDMA modification in these proteins. RNA interference-mediated depletion …

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Morphological Variation Of Rusty Crayfish Orconectes Rusticus (Cambaridae) With Gender And Local Scale Spatial Gradients, Luke Etchison, Stephen J. Jacquemin, Michael Allen, Mark Pyron Jan 2012

Morphological Variation Of Rusty Crayfish Orconectes Rusticus (Cambaridae) With Gender And Local Scale Spatial Gradients, Luke Etchison, Stephen J. Jacquemin, Michael Allen, Mark Pyron

Biological Sciences Faculty Publications

We tested for the influence of gender, stream, and urbanization on morphological variation in rusty crayfish (Orconectes rusticus) in an east-central Indiana, US watershed. We used geometric morphometrics to characterize shape and tested for differences among and within sites. Males had shallower rostrum, increased head width and length, decreased abdomen and cephalothorax width and length, and increased telson length compared to females. Morphology of males did not vary with stream or along an urban gradient. The morphology of females varied with stream and along an urban gradient. Female shapes from small creek sites were stouter and less fusiform …

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The Sign And Strength Of Plant-Soil Feedback For The Invasive Shrub, Lonicera Maackii, Varies In Different Soils, Kelly Schradin, Don Cipollini Jan 2012

The Sign And Strength Of Plant-Soil Feedback For The Invasive Shrub, Lonicera Maackii, Varies In Different Soils, Kelly Schradin, Don Cipollini

Biological Sciences Faculty Publications

Plants alter soil characteristics causing changes in their subsequent growth resulting in positive or negative feedback on both their own fitness and that of other plants. In a greenhouse study, we investigated whether the sign and strength of feedback changed across two distinct soil types, and whether effects were due to shifts in biotic or abiotic soil traits. Using soils from two different locations, we examined growth of the exotic invasive shrub, Lonicera maackii and the related native shrub, Diervilla lonicera, in unconditioned soils and in soils conditioned by previous growth of L. maackii, D. lonicera, and …

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Molecular Characterization And Tissue-Specific Gene Expression Of Dermacentor Variabilis Α-Catenin In Response To Rickettsial Infection, Piyanate Sunyakumthorn, Natthida Petchampai, Michael T. Kearney, Daniel E. Sonenshine, Kevin R. Macaluso Jan 2012

Molecular Characterization And Tissue-Specific Gene Expression Of Dermacentor Variabilis Α-Catenin In Response To Rickettsial Infection, Piyanate Sunyakumthorn, Natthida Petchampai, Michael T. Kearney, Daniel E. Sonenshine, Kevin R. Macaluso

Biological Sciences Faculty Publications

Alpha catenin is a cytoskeleton protein that acts as a regulator of actin rearrangement by forming an E-cadherin adhesion complex. In Dermacentor variabilis, a putative α-catenin (Dvα-catenin) was previously identified as differentially regulated in ovaries of ticks chronically infected with Rickettsia montanensis. To begin characterizing the role(s) of Dvα-catenin during rickettsial infection, the full-length Dvα-catenin cDNA was cloned and analysed. Comparative sequence analysis demonstrates a 3069-bp cDNA with a 2718-bp open reading frame with a sequence similar to Ixodes scapularis α-catenin. A portion of Dvα-catenin is homologous to the vinculin-conserved domain containing a putative …

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Reproductive Biology And Recruitment Of Xiphopenaeus Kroyeri In A Marine Protected Area In The Western Atlantic: Implications For Resource Management, Ariádine C. Almeida, J. Antonio Baeza, Vivian Fransozo, Antonio L. Castilho, Adilson Fransozo Jan 2012

Reproductive Biology And Recruitment Of Xiphopenaeus Kroyeri In A Marine Protected Area In The Western Atlantic: Implications For Resource Management, Ariádine C. Almeida, J. Antonio Baeza, Vivian Fransozo, Antonio L. Castilho, Adilson Fransozo

Biological Sciences Faculty Publications

The potential of a recently established marine protected area (MPA) in the Western Atlantic, Brazil, as a 'seed production' and nursery ground for Xiphopenaeus kroyeri, an intensively exploited penaeid shrimp, was investigated in an attempt to reveal any future benefit of this new MPA to adjacent populations experiencing heavy exploitation. Overall, we observed that males and females >12 and 20 mm carapace length, respectively, contributed the most to reproduction in the studied population. Reproductive activity of X. kroyeri was continuous at the MPA; 2 annual reproductive peaks were recorded from March to April and from November to December, which were …

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Fungal Endophytes Directly Increase The Competitive Effects Of An Invasive Forb, Erik T. Aschehoug, Kerry L. Metlen, Ragan M. Callaway, George Newcombe Jan 2012

Fungal Endophytes Directly Increase The Competitive Effects Of An Invasive Forb, Erik T. Aschehoug, Kerry L. Metlen, Ragan M. Callaway, George Newcombe

Biological Sciences Faculty Publications

Competitive outcomes among plants can vary in different abiotic and biotic conditions. Here we tested the effects of two phylotypes of Alternaria endophytes on the growth, competitive effects, and competitive responses of the exotic invasive forb Centaurea stoebe. Centaurea stoebe was a better competitor against North American grass species than grasses from its European home range in the absence of endophytes. However, one endophyte both increased the biomass of C. stoebe and reduced the competitive effect of North American grasses on C. stoebe. The competitive effects of C. stoebe on grass species native to North America were enhanced by both …

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The Effect Of Fire On Spatial Separation Between Wolves And Caribou, Hugh S. Robinson, Mark Hebblewhite, Nicholas J. Decesare, Jessie Whittington, Layla Neufeld, Mark Bradley, Marco Musiani Jan 2012

The Effect Of Fire On Spatial Separation Between Wolves And Caribou, Hugh S. Robinson, Mark Hebblewhite, Nicholas J. Decesare, Jessie Whittington, Layla Neufeld, Mark Bradley, Marco Musiani

Biological Sciences Faculty Publications

Fire management is an important conservation tool in Canada’s national parks. Fires can benefit some species, while others may be negatively impacted. We used GPS and VHF collar data for 47 wolves from 12 separate packs and 153 caribou from 5 separate herds, and resource selection analysis to model the effects of fire on these species’ habitat and potential interactions. Resource selection modeling showed that wolves select for burned areas and areas close to burns, presumably due to the presence of primary prey (i.e., elk and moose), while caribou avoid burns. Fire reduced the amount of high quality caribou habitat …

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Cyanobacteria Dominance In The Oligohaline Waters Of Back Bay, Virginia, Harold G. Marshall Jan 2012

Cyanobacteria Dominance In The Oligohaline Waters Of Back Bay, Virginia, Harold G. Marshall

Biological Sciences Faculty Publications

Back Bay and its flora have historically been influenced by the interaction of freshwater flow in combination with frequent intrusion of saline water into its basin. These events have resulted in a dynamic environmental setting influencing the abundance and composition of its phytoplankton community. Dominating these oligohaline waters is a diverse representation and high abundance of freshwater filamentous and colonial cyanobacteria. These include the nonheterocystous Planktolyngbya contorta, Planktolyngbya limnetica, and Pseudanabaena limnetica, taxa implicated as bloom producers in Bay waters with N:P molar ratios ranging from 23:1 to 74:1.

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Properties Of Lewis Lung Carcinoma Cells Surviving Curcumin Toxicity, Michael Eric Geusz, Dejun Yan Jan 2012

Properties Of Lewis Lung Carcinoma Cells Surviving Curcumin Toxicity, Michael Eric Geusz, Dejun Yan

Biological Sciences Faculty Publications

The anti-inflammatory agent curcumin can selectively eliminate malignant rather than normal cells. The present study examined the effects of curcumin on the Lewis lung carcinoma (LLC) cell line and characterized a subpopulation surviving curcumin treatments. Cell density was measured after curcumin was applied at concentrations between 10 and 60 μM for 30 hours. Because of the high cell loss at 60 μM, this dose was chosen to select for surviving cells that were then used to establish a new cell line. The resulting line had approximately 20% slower growth than the original LLC cell line and based on ELISA contained …

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Population Viability Analysis Of The Blue-Throated Macaw (Ara Glaucogularis) Using Individual-Based And Cohort-Based Pva Programs, Juan Luis Bouzat, Rosa I. Strem Jan 2012

Population Viability Analysis Of The Blue-Throated Macaw (Ara Glaucogularis) Using Individual-Based And Cohort-Based Pva Programs, Juan Luis Bouzat, Rosa I. Strem

Biological Sciences Faculty Publications

We developed a demographic model to perform a population viability analysis (PVA) of the Blue-throated Macaw (Ara glaucogularis), a critically endangered species endemic to Bolivia. PVA simulations were run using individual based (VORTEX 9.72) and cohort-based (RAMAS GIS 4.0) programs. A baseline simulation allowed for the assessment of the status of the species based on estimates of extinction risk and population declines under current conditions of abundance and habitat availability. The role of multiple demographic, environmental, and anthropogenic parameters was evaluated to assess changes affecting population declines and extinction risk. The baseline simulation showed that the Blue-throated Macaw has a …

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Unraveling The Determinants Of Protrusion Formation, Mita Varghese, Peter Gorsevski, Marilyn L. Cayer, Nancy S. Boudreau, Carol A. Heckman Jan 2012

Unraveling The Determinants Of Protrusion Formation, Mita Varghese, Peter Gorsevski, Marilyn L. Cayer, Nancy S. Boudreau, Carol A. Heckman

Biological Sciences Faculty Publications

A computerized morphometric classification technique based on latent factors reveals major protrusion classes: factors 4, 5, and 7. Previous work showed that factor 4 represented filopodia, 5 the distribution of lamellar cytoplasm, and 7 a blunt protrusion. We explore the relationship of focal contact (FC) characteristics and their integrated actin cables to factors values. The results show that FC maturation/cytoskeletal integration affects factor 5, because FC elongation/integration was correlated with its values. On the contrary, 7 values decreased with maturation, so cable or FC size or their integration must be restricted to form these protrusions. Where integration did occur, the …

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Extraction Of Dna From Plant And Fungus Tissues In Situ, Scott O. Rogers, Amal S. Abu Almakarem, Katie L. Heilman, Heather L. Conger, Yury M. Shtarkman Jan 2012

Extraction Of Dna From Plant And Fungus Tissues In Situ, Scott O. Rogers, Amal S. Abu Almakarem, Katie L. Heilman, Heather L. Conger, Yury M. Shtarkman

Biological Sciences Faculty Publications

Background: When samples are collected in the field and transported to the lab, degradation of the nucleic acids contained in the samples is frequently observed. Immediate extraction and precipitation of the nucleic acids reduces degradation to a minimum, thus preserving accurate sequence information. An extraction method to obtain high quality DNA in field studies is described. Findings. DNA extracted immediately after sampling was compared to DNA extracted after allowing the sampled tissues to air dry at 21°C for 48 or 72 hours. While DNA extracted from fresh tissues exhibited little degradation, DNA extracted from all tissues exposed to 21°C air …

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Plasticity Of Total And Intracellular Phosphorus Quotas In Microcystis Aeruginosa Cultures And Lake Erie Algal Assemblages, Robert Michael Mckay, Matthew A. Saxton, Robert J. Arnold, Richard A. Bourbonniere, Steven W. Wilhelm Jan 2012

Plasticity Of Total And Intracellular Phosphorus Quotas In Microcystis Aeruginosa Cultures And Lake Erie Algal Assemblages, Robert Michael Mckay, Matthew A. Saxton, Robert J. Arnold, Richard A. Bourbonniere, Steven W. Wilhelm

Biological Sciences Faculty Publications

Blooms of the potentially toxic cyanobacterium Microcystis are common events globally, and as a result significant resources continue to be dedicated to monitoring and controlling these events. Recent studies have shown that a significant proportion of total cell-associated phosphorus (P) in marine phytoplankton can be surface adsorbed; as a result studies completed to date do not accurately report the P demands of these organisms. In this study we measure the total cell-associated and intracellular P as well as growth rates of two toxic strains of Microcystis aeruginosa Kütz grown under a range of P concentrations. The results show that the …

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An Evaluation Of The Role Of Sensory Drive In The Evolution Of Lake Malawi Cichlid Fishes, Adam R. Smith, Moira J. Van Staaden, Karen L. Carleton Jan 2012

An Evaluation Of The Role Of Sensory Drive In The Evolution Of Lake Malawi Cichlid Fishes, Adam R. Smith, Moira J. Van Staaden, Karen L. Carleton

Biological Sciences Faculty Publications

Although the cichlids of Lake Malawi are an important model system for the study of sensory evolution and sexual selection, the evolutionary processes linking these two phenomena remain unclear. Prior works have proposed that evolutionary divergence is driven by sensory drive, particularly as it applies to the visual system.While evidence suggests that sensory drive has played a role in the speciation of Lake Victoria cichlids, the findings fromseveral lines of research on cichlids of LakeMalawi are not consistent with the primary tenets of this hypothesis. More specifically, three observations make the sensory drive model implausible in Malawi: (i) a lack …

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Genetic Diversity Of The Caribbean Spiny Lobster Virus, Panulirus Argus Virus 1 (Pav1), And The Discovery Of Pav1 In Lobster Postlarvae, Jessica Moss, Mark J. Butler Iv, Donald C. Behringer Jr., Jeffrey D. Shields Jan 2012

Genetic Diversity Of The Caribbean Spiny Lobster Virus, Panulirus Argus Virus 1 (Pav1), And The Discovery Of Pav1 In Lobster Postlarvae, Jessica Moss, Mark J. Butler Iv, Donald C. Behringer Jr., Jeffrey D. Shields

Biological Sciences Faculty Publications

Panulirus argus virus 1 (PaV1) is an unclassified, pathogenic virus first discovered in Caribbean spiny lobsters Panulirus argus from the Florida Keys, USA, and has since been confirmed in lobsters in other parts of the Caribbean. Several studies have examined the prevalence, pathogenicity, and population dynamics of the pathogen in the lobster host, but little is known about the genetic diversity of the virus. We analyzed a fragment of viral DNA from lobsters collected in the Florida Keys, which provided the first insight into the genetic diversity of PaV1. The variation in viral sequences, both within and between individual lobsters, …

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Successful Genotyping Of Microsatellites In The Woolly Mammoth, Yasuko Ishida, Alfred L. Roca, Stephen Fratpietro, Alex D. Greenwood Jan 2012

Successful Genotyping Of Microsatellites In The Woolly Mammoth, Yasuko Ishida, Alfred L. Roca, Stephen Fratpietro, Alex D. Greenwood

Biological Sciences Faculty Publications

Genetic analyses using ancient DNA from Pleistocene and early Holocene fossils have largely relied on mitochondrial DNA (mtDNA) sequences. Among woolly mammoths, Mammuthus primigenius, mtDNA analyses have identified 2 distinct clades (I and II) that diverged 1-2 Ma. Here, we establish that microsatellite markers can be effective on Pleistocene samples, successfully genotyping woolly mammoth specimens at 2 loci. Although significant differentiation at the 2 microsatellite loci was not detected between 16 clade I and 4 clade II woolly mammoths, our results demonstrate that the nuclear population structure of Pleistocene species can be examined using fast-evolving nuclear microsatellite markers.

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Phycoerythrin-Specific Bilin Lyase-Isomerase Controls Blue-Green Chromatic Acclimation In Marine Synechococcus, Wendy M. Schluchter, Avijit Biswas, Frédéric Partensky, J. A. Karty, Laurence Garczarek, A. Gutu, David M. Kehoe, A. Shukla, N. Blot, L. A. Hammad Jan 2012

Phycoerythrin-Specific Bilin Lyase-Isomerase Controls Blue-Green Chromatic Acclimation In Marine Synechococcus, Wendy M. Schluchter, Avijit Biswas, Frédéric Partensky, J. A. Karty, Laurence Garczarek, A. Gutu, David M. Kehoe, A. Shukla, N. Blot, L. A. Hammad

Biological Sciences Faculty Publications

The marine cyanobacterium Synechococcus is the second most abundant phytoplanktonic organism in the world's oceans. The ubiquity of this genus is in large part due to its use of a diverse set of photosynthetic light-harvesting pigments called phycobiliproteins, which allow it to efficiently exploit a wide range of light colors. Here we uncover a pivotal molecular mechanism underpinning a widespread response among marine Synechococcus cells known as type IV chromatic acclimation (CA4). During this process, the pigmentation of the two main phycobiliproteins of this organism, phycoerythrins I and II, is reversibly modified to match changes in the ambient light color …

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Patterns Of Extinction Risk And Threat For Marine Vertebrates And Habitat-Forming Species In The Tropical Eastern Pacific, Beth A. Polidoro, T. Brooks, Kent E. Carpenter, G. J. Edgar, S Henderson, J. Sanciangco, D. R. Robertson Jan 2012

Patterns Of Extinction Risk And Threat For Marine Vertebrates And Habitat-Forming Species In The Tropical Eastern Pacific, Beth A. Polidoro, T. Brooks, Kent E. Carpenter, G. J. Edgar, S Henderson, J. Sanciangco, D. R. Robertson

Biological Sciences Faculty Publications

Marine conservation activities around the globe are largely undertaken in the absence of comprehensive species-specific information. To address this gap, complete regional species assemblages of major marine taxa are being progressively assessed against the Categories and Criteria of the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. The present study is the first analysis of entire major components of the biota of a large marine biogeographic region conducted in the Tropical Eastern Pacific (TEP). It is based on recently completed IUCN Red List assessments for all known species of bony and cartilaginous shorefishes, corals, mangroves, …

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Protandric Simultaneous Hermaphroditism In Parhippolyte Misticia (Clark, 1989) (Caridea: Hippolytidae): Implications For The Evolution Of Mixed Sexual Systems In Shrimp, Hitoshi Onaga, G. Curt Fiedler, J. Antonio Baeza Jan 2012

Protandric Simultaneous Hermaphroditism In Parhippolyte Misticia (Clark, 1989) (Caridea: Hippolytidae): Implications For The Evolution Of Mixed Sexual Systems In Shrimp, Hitoshi Onaga, G. Curt Fiedler, J. Antonio Baeza

Biological Sciences Faculty Publications

The sexual system of the shrimp Parhippolyte misticia (Clark, 1989), inhabiting the rocky subtidal at Okinawa, Japan and Kimbe Bay, Papua New Guinea, was examined. Dissections suggested that the population consisted of male phase (MP) and functional simultaneous euhermaphrodite (EH) individuals. MPs have cincinulli and appendices masculinae on the first and second pair of pleopods, respectively, gonopores located at the coxae of the third pair of walking legs, and ovotestes with a well-developed male portion containing sperm, but an undeveloped female portion. EHs lacked appendices masculinae and cincinulli. However, they have male gonopores and ovotestes with well-developed ovaries containing mature …

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Expansion Dating: Calibrating Molecular Clocks In Marine Species From Expansions Onto The Sunda Shelf Following The Last Glacial Maximum, Eric D. Crandall, Elizabeth J. Sbrocco, Timery S. Deboer, Paul H. Barber, Kent E. Carpenter Jan 2012

Expansion Dating: Calibrating Molecular Clocks In Marine Species From Expansions Onto The Sunda Shelf Following The Last Glacial Maximum, Eric D. Crandall, Elizabeth J. Sbrocco, Timery S. Deboer, Paul H. Barber, Kent E. Carpenter

Biological Sciences Faculty Publications

The rate of change in DNA is an important parameter for understanding molecular evolution and hence for inferences drawn from studies of phylogeography and phylogenetics. Most rate calibrations for mitochondrial coding regions in marine species have been made from divergence dating for fossils and vicariant events older than 1-2 My and are typically 0.5-2% per lineage per million years. Recently, calibrations made with ancient DNA (aDNA) from younger dates have yielded faster rates, suggesting that estimates of the molecular rate of change depend on the time of calibration, decaying from the instantaneous mutation rate to the phylogenetic substitution rate. aDNA …

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Marine Invertebrate Life, Rachael Kemp, Howard Peters, Louise Allcock, Kent Carpenter, David Obura, Beth Polidoro, Nadia Richman Jan 2012

Marine Invertebrate Life, Rachael Kemp, Howard Peters, Louise Allcock, Kent Carpenter, David Obura, Beth Polidoro, Nadia Richman

Biological Sciences Faculty Publications

Marine invertebrates are key components of all marine ecosystems, and play critical roles in essential ecological processes, food provision for humans, and diverse and productive food webs. Despite their importance, the vast majority of marine invertebrates are very poorly known. Research has tended to focus on the larger, more conspicuous and economically important species. Humans have long exploited the margins of pelagic ecosystems, but over the past five decades, rapid technological advancement has allowed more routine access to deeper waters [1]. Increasing exploration into the oceans that cover 70% of the world's surface has led to rapid advancement of species …

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An Epidemiological Model Of Rift Valley Fever With Spatial Dynamics, Tianchan Niu, Holly D. Gaff, Yiannis E. Papelis, David M. Hartley Jan 2012

An Epidemiological Model Of Rift Valley Fever With Spatial Dynamics, Tianchan Niu, Holly D. Gaff, Yiannis E. Papelis, David M. Hartley

Biological Sciences Faculty Publications

As a category A agent in the Center for Disease Control bioterrorism list, Rift Valley fever (RVF) is considered a major threat to the United States (USA). Should the pathogen be intentionally or unintentionally introduced to the continental USA, there is tremendous potential for economic damages due to loss of livestock, trade restrictions, and subsequent food supply chain disruptions. We have incorporated the effects of space into a mathematical model of RVF in order to study the dynamics of the pathogen spread as affected by the movement of humans, livestock, and mosquitoes. The model accounts for the horizontal transmission of …

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In Vitro Propagation Of Candidatus Rickettsia Andeanae Isolated From Amblyomma Maculatum, Alison Luce-Fedrow, Chelsea Wright, Holly D. Gaff, Daniel E. Sonenshine, Wayne L. Hynes, Allen L. Richards Jan 2012

In Vitro Propagation Of Candidatus Rickettsia Andeanae Isolated From Amblyomma Maculatum, Alison Luce-Fedrow, Chelsea Wright, Holly D. Gaff, Daniel E. Sonenshine, Wayne L. Hynes, Allen L. Richards

Biological Sciences Faculty Publications

Candidatus Rickettsia andeanae was identified during an investigation of a febrile outbreak in northwestern Peru (2002). DNA sequencing from two ticks (Amblyomma maculatum, Ixodes boliviensis) collected during the investigation revealed a novel Rickettsia agent with similarity to the spotted fever group rickettsiae. Since then, Candidatus R. similar to andeanae has been detected in A. maculatum ticks collected in the southeastern and southcentral United States, Argentina, and Peru. To date, Candidatus R. andeanae has not been successfully cultivated in the laboratory. We present evidence for the continuous cultivation in three cell lines of Candidatus R. similar to …

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Unusually High Body Mass In Virginia Meadow Voles, Sara B. Longtin, Robert K. Rose Jan 2012

Unusually High Body Mass In Virginia Meadow Voles, Sara B. Longtin, Robert K. Rose

Biological Sciences Faculty Publications

We used monthly capture-mark-recapture information to determine growth rates and life spans for 2 populations of meadow voles studied for 28 and 29 months in eastern Virginia in order to learn whether the exceptionally large body masses of some voles were due to rapid growth, long lives, or both. On 1 study grid, 64 males (19%) and 43 nonpregnant females (11%) were ≥70 g, with the largest male being 89 g. Mostly positive growth rates (averaging 1.1-3.9 g/month) were recorded, even in autumn and winter months, times when meadow voles are losing mass in northern populations, where most studies of …

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Brooding, Provisioning, And Compensatory Care In The Cooperatively Breeding Acorn Woodpecker, Walter D. Koenig, Eric L. Walters Jan 2012

Brooding, Provisioning, And Compensatory Care In The Cooperatively Breeding Acorn Woodpecker, Walter D. Koenig, Eric L. Walters

Biological Sciences Faculty Publications

We analyzed reproductive investment in parental care (brooding and the provisioning of nestlings) in the acorn woodpecker (Melanerpes formicivorus), a cooperatively breeding species in which both polygynandry and helping-at-the-nest are common. As predicted based on the strategies pursued by birds of different sex and status, breeders generally invested more in parental care than helpers, and breeder females invested more than breeder males. Contrary to expectations, however, the degree to which individuals reduced their effort with increasing group size (i.e., patterns of load lightening or compensatory care) did not match overall investment. Instead, as group size increased, there was …

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