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Identifying Factors That Influence Terrorist Decisions And Target Selection, Barry C. Ezell, Joshua Behr, Andrew Collins Jan 2012

Identifying Factors That Influence Terrorist Decisions And Target Selection, Barry C. Ezell, Joshua Behr, Andrew Collins

VMASC Publications

Currently, the U.S. Department of Homeland Security (DHS) elicits probabilistic judgements from the intelligence community on actions terrorists may take to attack the continental U.S. For example, how likely is the adversary to choose agent 'x' over 'y' or target 'a' over target 'b'? Eliciting these types of judgements is difficult and time consuming. The National Academies and others have suggested that a better approach may be to elicit information on adversary's preferences, perceptions, and capabilities and use this information to calculate probabilities of interest to DHS. Some terrorist groups are thinking about using weapons of mass destruction (WMD), each …

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More Than A One-Trick Pony: Exploring The Contours Of A Multi-Sector Covener, Madeleine W. Mcnamara, John C. Morris Jan 2012

More Than A One-Trick Pony: Exploring The Contours Of A Multi-Sector Covener, Madeleine W. Mcnamara, John C. Morris

School of Public Service Faculty Publications

Today's managers must find ways to identify and sustain productive relationships within multi-sector collaborative arrangements. This paper explores empirically the activities of a convener based on tasks identified by Agranoff and McGuire (2001) and applies this framework to the case of Virginia's Coastal Zone Management Program (VCZMP). We find that the convener displays characteristics described by Agranoff and McGuire, as well as characteristics of traditional hierarchical managers. This research suggests that both sets of skills are necessary for effective multi-sector collaborative governance.

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Protein Structure Networks, Lesley H. Greene Jan 2012

Protein Structure Networks, Lesley H. Greene

Chemistry & Biochemistry Faculty Publications

The application of the field of network science to the scientific disciplines of structural biology and biochemistry, have yielded important new insights into the nature and determinants of protein structures, function, dynamics and the folding process. Advancements in further understanding protein relationships through network science have also reshaped the way we view the connectivity of proteins in the protein universe. The canonical hierarchical classification can now be visualized for example, as a protein fold continuum. This review will survey several key advances in the expanding area of research being conducted to study protein structures and folding using network approaches.

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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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Identification And Implementation Of Patterns Towards A Model Of Environmental Sustainability, S. Jimmy Gandhi, Santiago Perez, Danial Rushton, Robert Cloutier, Ipek Bozkurt, C. Ariel Pinto Jan 2012

Identification And Implementation Of Patterns Towards A Model Of Environmental Sustainability, S. Jimmy Gandhi, Santiago Perez, Danial Rushton, Robert Cloutier, Ipek Bozkurt, C. Ariel Pinto

Engineering Management & Systems Engineering Faculty Publications

Much like the Quality Revolution did in the 1980's, corporate sustainability has the potential to drive significant changes in the processes and structure of various organizations in the coming decade. With a rapidly growing global population and an ever increasing global demand for resources (Population-Resource-Center, 2012). Sustainability has emerged as one of the primary challenges that organizations will have to deal with in the 21st century. An increasing realization among business executives that profitability by itself is not enough as a measure of success is also driving the increased adoption of sustainable practices in the corporate world (Lowitt and Grimsley, …

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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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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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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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Molecular Phylogenetics Of Alternanthera (Gomphrenoideae, Amaranthaceae): Resolving A Complex Taxonomic History Caused By Different Interpretations Of Morphological Characters In A Lineage With C4 And C3-C4 Intermediate Species, Ivonne Sánchez-Del Pino, Timothy J. Motley, Thomas Borsch Jan 2012

Molecular Phylogenetics Of Alternanthera (Gomphrenoideae, Amaranthaceae): Resolving A Complex Taxonomic History Caused By Different Interpretations Of Morphological Characters In A Lineage With C4 And C3-C4 Intermediate Species, Ivonne Sánchez-Del Pino, Timothy J. Motley, Thomas Borsch

Biological Sciences Faculty Publications

Aternanthera (Amaranthaceae) is a diverse genus (80-200 species) largely restricted to the American Tropics. With Pedersenia and Tidestromia, it makes up the Alternantheroid clade in Gomphrenoideae. Parsimony and Bayesian analyses of nucleotide sequences of nuclear (ITS) and plastid (rpl16, trnL-F) and morphological characters identify that the capitate stigma of Alternanthera is a synapomorpy within the Alternantheroids. Within Alternanthera, two major clades were resolved, both of which were marked by otherwise homoplasious characters of the gynoecium: Clade A [99% jackknife (JK); 1.0 posterior probability (PP)] with nine species and Clade B (60% JK; 0.98 PP) with 22 …

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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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A Global Diatom Database- Abundance, Biovolume And Biomass In The World Ocean, K. Leblanc, J. Aristegui, L. Armand, P. Assmy, B. Becker, A. Bode, E. Breton, V. Cornet, J. Gibson, M. P. Gosselin, H. Marshall Jan 2012

A Global Diatom Database- Abundance, Biovolume And Biomass In The World Ocean, K. Leblanc, J. Aristegui, L. Armand, P. Assmy, B. Becker, A. Bode, E. Breton, V. Cornet, J. Gibson, M. P. Gosselin, H. Marshall

Biological Sciences Faculty Publications

Phytoplankton identification and abundance data are now commonly feeding plankton distribution databases worldwide. This study is a first attempt to compile the largest possible body of data available from different databases as well as from individual published or unpublished datasets regarding diatom distribution in the world ocean. The data obtained originate from time series studies as well as spatial studies. This effort is supported by the Marine Ecosystem Model Inter-Comparison Project (MAREMIP), which aims at building consistent datasets for the main plankton functional types (PFTs) in order to help validate biogeochemical ocean models by using carbon (C) biomass derived from …

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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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Are Low Wages Risk Factors For Hypertension?, J. Paul Leigh, Juan Du Jan 2012

Are Low Wages Risk Factors For Hypertension?, J. Paul Leigh, Juan Du

Economics Faculty Publications

Objective: Socio-economic status (SES) is strongly correlated with hypertension. But SES has several components, including income and correlations in cross-sectional data need not imply SES is a risk factor. This study investigates whether wages-the largest category within income-are risk factors. Methods: We analysed longitudinal, nationally representative US data from four waves (1999, 2001, 2003 and 2005) of the Panel Study of Income Dynamics. The overall sample was restricted to employed persons age 25-65 years, n = 17 295. Separate subsamples were constructed of persons within two age groups (25-44 and 45-65 years) and genders. Hypertension incidence was self-reported based on …

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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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Testing The Role Of Male-Male Competition In The Evolution Of Sexual Dimorphism: A Comparison Between Two Species Of Porcelain Crabs, J. Antonio Baeza, Cynthia M. Asorey Jan 2012

Testing The Role Of Male-Male Competition In The Evolution Of Sexual Dimorphism: A Comparison Between Two Species Of Porcelain Crabs, J. Antonio Baeza, Cynthia M. Asorey

Biological Sciences Faculty Publications

Theory predicts marked sexual dimorphism in terms of body size and body structures used as weapons (e.g. chelipeds) in gonochoric species with intense male sexual competition for receptive females and reduced or no sexual dimorphism in species where competition among males is trivial. We tested this hypothesis using a pair of closely-related species of symbiotic porcelain crabs as a model. In one species that inhabits sea anemones solitarily, competition among males for receptive females is unimportant. In a second species that dwells as dense aggregations on sea urchins, malemale competition for sexual partners is recurrent. We expected considerable sexual dimorphism …

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Effects Of Root-Zone Temperature And N, P, And K Supplies On Nutrient Uptake Of Cucumber (Cucumis Sativus L.) Seedlings In Hydroponics, Qiuyan Yan, Zengqiang Duan, Jingdong Mao, Xun Li, Fei Dong Jan 2012

Effects Of Root-Zone Temperature And N, P, And K Supplies On Nutrient Uptake Of Cucumber (Cucumis Sativus L.) Seedlings In Hydroponics, Qiuyan Yan, Zengqiang Duan, Jingdong Mao, Xun Li, Fei Dong

Chemistry & Biochemistry Faculty Publications

The nutrient uptake and allocation of cucumber (Cucumis sativus L.) seedlings at different root-zone temperatures (RZT) and different concentrations of nitrogen (N), phosphorus (P), and potassium (K) nutrients were examined. Plants were grown in a nutrient solution for 30 d at two root-zone temperatures (a diurnally fluctuating ambient 10°C-RZT and a constant 20° C-RZT) with the aerial parts of the plants maintained at ambient temperature (10°C -30°C). Based on a Hoagland nutrient solution, seven N, P, and K nutrient concentrations were supplied to the plants at each RZT. Results showed that total plant and shoot dry weights under …

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Protein Folding By 'Levels Of Separation': A Hypothesis, Lesley H. Greene, Terri M. Grant Jan 2012

Protein Folding By 'Levels Of Separation': A Hypothesis, Lesley H. Greene, Terri M. Grant

Chemistry & Biochemistry Faculty Publications

The protein folding process has been studied both computationally and experimentally for over 30 years. To date there is no detailed mechanism to explain the formation of long-range interactions between the transition and native states. Long-range interactions are the principle determinants of the tertiary structure. We present a theoretical model which proposes a mechanism for the acquisition of these interactions as they form in a modified version of ‘degrees of separation’, that we term ‘levels of separation’. It is based on the integration of network science and biochemistry. (C) 2012 Federation of European Biochemical Societies.

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End-To-End Models: Management Applications, John H. Steele, Eileen E. Hofmann, Dian J. Gifford Jan 2012

End-To-End Models: Management Applications, John H. Steele, Eileen E. Hofmann, Dian J. Gifford

CCPO Publications

Preface to the 2012 issue of Progress in Oceanography.

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Circulation And Water Properties And Their Relationship To The Oyster Disease Msx In Delaware Bay, Zhiren Wang, Dale B. Haidvogel, David Bushek, Susan E. Ford, Eileen E. Hofmann, Eric N. Powell, John Wilkin Jan 2012

Circulation And Water Properties And Their Relationship To The Oyster Disease Msx In Delaware Bay, Zhiren Wang, Dale B. Haidvogel, David Bushek, Susan E. Ford, Eileen E. Hofmann, Eric N. Powell, John Wilkin

CCPO Publications

We apply a high-resolution hydro-dynamical model to investigate the role of physical factors influencing infection prevalence of Haplosporidium nelsoni, causative agent of MSX disease in the eastern oyster (Crassostrea virginica), in Delaware Bay, USA. Validation studies conducted for the years 2000 and 2010-2011 confirm that the model, based upon the Regional Ocean Modeling System, has significant skill in the recovery of observed water level, temperature, salinity, and velocity. Multi-year simulations are performed for periods representing temporal and spatial variations in H. nelsoni infection prevalence (1974-76, 1979-81, 1984-86, 1990-92, and 2006-09) to assess the degree to which the …

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The Rise And Fall Of Crassostrea Virginica Oyster Reefs: The Role Of Disease And Fishing In Their Demise And A Vignette On Their Management, Eric N. Powell, John M. Klinck, Kathryn Ashton-Alcox, Eileen E. Hofmann, Jason Morson Jan 2012

The Rise And Fall Of Crassostrea Virginica Oyster Reefs: The Role Of Disease And Fishing In Their Demise And A Vignette On Their Management, Eric N. Powell, John M. Klinck, Kathryn Ashton-Alcox, Eileen E. Hofmann, Jason Morson

CCPO Publications

We describe a model designed to simulate the shell carbonate budget of an oyster reef.We identify five parameters descriptive of basic characteristics of the shell carbonate budget of a reef that limit simulation accuracy. Two describe the TAZ (taphonomically-active zone) and the distribution of shell carbonate within it. One is the taphonomic rate in the TAZ. Two determine the volume contribution of shell carbonate and the taphonomic loss rate within the reef framework. For Mid-Atlantic estuaries, model simulations suggest that reef accretion only occurs if oyster abundance is near carrying capacity. Simulations further suggest that reef accretion is infeasible for …

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Circulation And Behavior Controls On Dispersal Of Eastern Oyster (Crassostrea Virginica) Larvae In Delaware Bay, Diego A. Narvaez, John M. Klinck, Eric N. Powell, Eileen E. Hofmann, John Wilkin, Dale B. Haidvogel Jan 2012

Circulation And Behavior Controls On Dispersal Of Eastern Oyster (Crassostrea Virginica) Larvae In Delaware Bay, Diego A. Narvaez, John M. Klinck, Eric N. Powell, Eileen E. Hofmann, John Wilkin, Dale B. Haidvogel

CCPO Publications

The degree of genetic connectivity among populations in a metapopulation has direct consequences for species evolution, development of disease resistance, and capacity of a metapopulation to adapt to climate change. This study used a metapopulation model that integrates population dynamics, dispersal, and genetics within an individual-based model framework to examine the mechanisms and dynamics of genetic connectivity within a metapopulation. The model was parameterized to simulate four populations of oysters (Crassostrea virginica) from Delaware Bay on the mid-Atlantic coast of the United States. Differences among the four populations include a strong spatial gradient in mortality, a spatial gradient …

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Modeling The Dispersal Of Eastern Oyster (Crassostrea Virginica) Larvae In Delaware Bay, Diego A. Narvaez, John M. Klinck, Eric N. Powell, Eileen E. Hofmann, John Wilkin, Dale B. Haidvogel Jan 2012

Modeling The Dispersal Of Eastern Oyster (Crassostrea Virginica) Larvae In Delaware Bay, Diego A. Narvaez, John M. Klinck, Eric N. Powell, Eileen E. Hofmann, John Wilkin, Dale B. Haidvogel

CCPO Publications

The interactions of circulation and growth processes in determining the horizontal distribution of eastern oyster (Crassostrea virginica) larvae in the Delaware Bay estuary were investigated with a coupled circulation-individual-based larvae model that used environmental conditions from the spawning seasons (mid-June to mid-September) of 1984, 1985, 1986, 2000, and 2001. Particles, representing oyster larvae, were released at five-day intervals from areas in Delaware Bay that correspond to natural oyster reefs. The simulated larval development time was used to estimate potential larval success, determined by the percent of larvae that successfully reached settlement size (330 µm) within the planktonic larval …

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Can Oysters Crassostrea Virginica Develop Resistance To Dermo Disease In The Field: The Impediment Posed By Climate Cycles, Eric N. Powell, John M. Klinck, Ximing Guo, Eileen E. Hofmann, Susan E. Ford, David Bushek Jan 2012

Can Oysters Crassostrea Virginica Develop Resistance To Dermo Disease In The Field: The Impediment Posed By Climate Cycles, Eric N. Powell, John M. Klinck, Ximing Guo, Eileen E. Hofmann, Susan E. Ford, David Bushek

CCPO Publications

Populations of eastern oysters, Crassostrea virginica, are commonly limited by mortality from dermo disease. Little development of resistance to Perkinsus marinus, the dermo pathogen, has occurred, despite the high mortality rates and frequency of epizootics. Can the tendency of the parasite to exhibit cyclic epizootics limit the oyster's response to the disease despite the presence of alleles apparently conferring disease resistance? We utilize a gene-based population dynamics model to simulate the development of disease resistance in Crassostrea virginica populations exposed to cyclic mortality encompassing periodicities expected of dermo disease over the geographic range at which epizootics have been …

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Does Large-Scale Ocean Circulation Structure Life History Connectivity In Antarctic Toothfish (Dissostichus Mawsoni)?, Julian Ashford, Michael S. Dinniman, Cassandra Brooks, Allen H. Andrews, Eileen E. Hofmann, Gregor Cailliet, Christopher Jones, Nakul Ramanna Jan 2012

Does Large-Scale Ocean Circulation Structure Life History Connectivity In Antarctic Toothfish (Dissostichus Mawsoni)?, Julian Ashford, Michael S. Dinniman, Cassandra Brooks, Allen H. Andrews, Eileen E. Hofmann, Gregor Cailliet, Christopher Jones, Nakul Ramanna

CCPO Publications

A multidisciplinary approach incorporating otolith chemistry, age data, and numerical Lagrangian particle simulations indicated a single, self-recruiting population of Antarctic toothfish (Dissostichus mawsoni) in the Southeast Pacific Basin (SPB) and Ross Sea, with a life history structured by the large-scale circulation. Chemistry deposited prior to capture along otolith edges demonstrated strong environmental heterogeneity, yet the chemistry in otolith nuclei, deposited during early life, showed no differences. Age data showed only adult fish in catches on the Pacific-Antarctic Ridge in the SPB and structuring of life stages consistent with transport pathways from the northern Ross Sea. Lagrangian particle simulations …

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A Conceptual Model Of An Arctic Sea, P. St-Laurent, F. Straneo, D. G. Barber Jan 2012

A Conceptual Model Of An Arctic Sea, P. St-Laurent, F. Straneo, D. G. Barber

CCPO Publications

We propose a conceptual model for an Arctic sea that is driven by river runoff, atmospheric fluxes, sea ice melt/growth, and winds. The model domain is divided into two areas, the interior and boundary regions, that are coupled through Ekman and eddy fluxes of buoyancy. The model is applied to Hudson and James Bays (HJB, a large inland basin in northeastern Canada) for the period 1979-2007. Several yearlong records from instruments moored within HJB show that the model results are consistent with the real system. The model notably reproduces the seasonal migration of the halocline, the baroclinic boundary current, spatial …

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A Shell-Neutral Modeling Approach Yields Sustainable Oyster Harvest Estimates: A Retrospective Analysis Of The Louisiana State Primary Seed Grounds, Thomas M. Soniat, John M. Klinck, Eric N. Powell, Nathan Cooper, Mahdi Abdelguerfi, Eileen E. Hofmann, Janak Dahal, Shengru Tu, John Finigan, Benjamin S. Eberline, Jerome F. La Peyre, Megan K. La Peyre, Fareed Qaddoura Jan 2012

A Shell-Neutral Modeling Approach Yields Sustainable Oyster Harvest Estimates: A Retrospective Analysis Of The Louisiana State Primary Seed Grounds, Thomas M. Soniat, John M. Klinck, Eric N. Powell, Nathan Cooper, Mahdi Abdelguerfi, Eileen E. Hofmann, Janak Dahal, Shengru Tu, John Finigan, Benjamin S. Eberline, Jerome F. La Peyre, Megan K. La Peyre, Fareed Qaddoura

CCPO Publications

A numerical model is presented that defines a sustainability criterion as no net loss of shell, and calculates a sustainable harvest of seed (<75 mm) and sack or market oysters (>= 75 mm). Stock assessments of the Primary State Seed Grounds conducted east of the Mississippi from 2009 to 2011 show a general trend toward decreasing abundance of sack and seed oysters. Retrospective simulations provide estimates of annual sustainable harvests. Comparisons of simulated sustainable harvests with actual harvests show a trend toward unsustainable harvests toward the end of the time series. Stock assessments combined with shell-neutral models can be used to estimate sustainable harvest and manage …

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Oceanic Controls On The Mass Balance Of Wilkins Ice Shelf, Antarctica, Laurie Padman, Daniel P. Costs, M. S. Dinniman, Helen A. Fricker, Michael E. Goebel, Luis A. Huckstadt, Angelika Humbert, Ian Joughin, Jan T. M. Lenaerts, Stefan R. M. Ligtenberg, Ted Scambos, Michiel R. Van Den Broeke Jan 2012

Oceanic Controls On The Mass Balance Of Wilkins Ice Shelf, Antarctica, Laurie Padman, Daniel P. Costs, M. S. Dinniman, Helen A. Fricker, Michael E. Goebel, Luis A. Huckstadt, Angelika Humbert, Ian Joughin, Jan T. M. Lenaerts, Stefan R. M. Ligtenberg, Ted Scambos, Michiel R. Van Den Broeke

CCPO Publications

Several Antarctic Peninsula (AP) ice shelves have lost significant fractions of their volume over the past decades, coincident with rapid regional climate change. Wilkins Ice Shelf (WIS), on the western side of the AP, is the most recent, experiencing a sequence of large calving events in 2008 and 2009. We analyze the mass balance for WIS for the period 1992-2008 and find that the averaged rate of ice-shelf thinning was similar to 0.8 m a(-1), driven by a mean basal melt rate of < w(b)> = 1.3 +/- 0.4 m a(-1). Interannual variability was large, associated with changes in both surface mass …

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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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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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