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Dreissenid Mussels Are Not A “Dead End” In Great Lakes Food Webs, Charles P. Madenjian, Steven A. Pothoven, Philip J. Schneeberger, Mark P. Ebener, Lloyd C. Mohr, Thomas F. Nalepa, James R. Bence 2010 U.S. Geological Survey

Dreissenid Mussels Are Not A “Dead End” In Great Lakes Food Webs, Charles P. Madenjian, Steven A. Pothoven, Philip J. Schneeberger, Mark P. Ebener, Lloyd C. Mohr, Thomas F. Nalepa, James R. Bence

Publications, Agencies and Staff of the U.S. Department of Commerce

Dreissenid mussels have been regarded as a “dead end” in Great Lakes food webs because the degree of predation on dreissenid mussels, on a lakewide basis, is believed to be low. Waterfowl predation on dreissenid mussels in the Great Lakes has primarily been confined to bays, and therefore its effects on the dreissenid mussel population have been localized rather than operating on a lakewide level. Based on results from a previous study, annual consumption of dreissenid mussels by the round goby (Neogobius melanostomus) population in central Lake Erie averaged only 6 kilotonnes (kt; 1 kt=one thousand metric tons) during ...


Social Cohesion Among Kin, Gene Flow Without Dispersal And The Evolution Of Population Genetic Structure In The Killer Whale (Orcinus Orca), M. Pilot, M. E. Dahlheim, A. R. Hoelzel 2010 School of Biological and Biomedical Sciences, University of Durham, Durham, UK

Social Cohesion Among Kin, Gene Flow Without Dispersal And The Evolution Of Population Genetic Structure In The Killer Whale (Orcinus Orca), M. Pilot, M. E. Dahlheim, A. R. Hoelzel

Publications, Agencies and Staff of the U.S. Department of Commerce

In social species, breeding system and gregarious behavior are key factors influencing the evolution of large-scale population genetic structure. The killer whale is a highly social apex predator showing genetic differentiation in sympatry between populations of foraging specialists (ecotypes), and low levels of genetic diversity overall. Our comparative assessments of kinship, parentage and dispersal reveal high levels of kinship within local populations and ongoing male-mediated gene flow among them, including among ecotypes that are maximally divergent within the mtDNA phylogeny. Dispersal from natal populations was rare, implying that gene flow occurs without dispersal, as a result of reproduction during temporary ...


Mandibular Fractures In Short-Finned Pilot Whales, Globicephala Macrorhynchus, Mollie Sue Oremland, Bernadette Allen, P J. Clapham, Michael Moore, Charley Potter, James G. Mead 2010 Boston University, Boston, Massachusetts

Mandibular Fractures In Short-Finned Pilot Whales, Globicephala Macrorhynchus, Mollie Sue Oremland, Bernadette Allen, P J. Clapham, Michael Moore, Charley Potter, James G. Mead

Publications, Agencies and Staff of the U.S. Department of Commerce

This study’s objective was to investigate mandibular fractures in 50 short-finned pilot whales, Globicephala macrorhynchus, from two mass strandings. Based on current theories that this species is sexually dimorphic and polygynous, hypotheses were: (1) males should suffer more frequent or more substantial mandibular fractures than should females, and (2) fracture occurrence should increase with male reproductive maturity and potential correlates of maturity, such as age and length. Fractures were described and correlated with physical characteristics to infer possible explanations for injuries. Mandibular fractures were surprisingly common in males and females, being found in more than half of the animals ...


Foraging Effort Of Juvenile Steller Sea Lions Eumetopias Jubatus With Respect To Heterogeneity Of Sea Surface Temperature, Michelle E. Lander, Thomas R. Loughlin, Miles G. Logsdon, Glenn R. VanBlaricom, Brian Fadely 2010 National Marine Mammal Laboratory

Foraging Effort Of Juvenile Steller Sea Lions Eumetopias Jubatus With Respect To Heterogeneity Of Sea Surface Temperature, Michelle E. Lander, Thomas R. Loughlin, Miles G. Logsdon, Glenn R. Vanblaricom, Brian Fadely

Publications, Agencies and Staff of the U.S. Department of Commerce

Among many other factors, the decline of the western distinct population segment of Steller sea lions Eumetopias jubatus in Alaska (USA) has been attributed to changes in the distribution or abundance of prey due to the cumulative effects of fisheries and large-scale climate change. However, the depletion of localized prey resources due to small-scale environmental variability and perturbations may be impeding recovery, resulting in the need to understand how the environment currently affects this species on smaller spatial and temporal scales. The objective of this study, there-fore, was to assess how Steller sea lions respond to changes in localized environmental ...


Meridional Patterns In The Deep Scattering Layers And Top Predator Distribution In The Central Equatorial Pacific, Elliott L. Hazen, David W. Johnston 2010 NOAA SWFSC Pacific Fisheries Environmental Lab

Meridional Patterns In The Deep Scattering Layers And Top Predator Distribution In The Central Equatorial Pacific, Elliott L. Hazen, David W. Johnston

Publications, Agencies and Staff of the U.S. Department of Commerce

The deep scattering layers (DSL) in the central equatorial Pacific form an important prey resource in a relatively oligotrophic habitat. In March of 2006, we used a calibrated 38-kHz SIMRAD EK60 scientific sonar to assess the spatial distribution of the deep scattering layer relative to broad-scale oceanographic features and fine-scale physical and biological measurements. We conducted a single continuous transect from approximately 10°S to 20°N at 170°W while measuring acoustic backscatter, current velocity and direction, temperature, salinity, oxygen, and fluorescence with depth, coincident with marine mammal occurrence. These data were combined with remotely sensed sea surface height ...


Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters 2010 UNL

Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters

Dissertations & Theses in Natural Resources

Invasive plant species are widely recognized as a major threat to biodiversity and ecosystem stability. Wetland ecosystems tend to be much more susceptible to invasions because of their location on the landscape where water, nutrients, and the impacts of disturbances accumulate. Invasive plants have the ability to alter ecosystem processes and community/population dynamics. The ability of invasive plants to alter these processes can have profound economic consequences. In the United States, control of invasive wetland species alone costs approximately 155 million dollars annually. The state of Nebraska spends 2 million dollars annually controlling invasive plant species in the Platte ...


Connection To Nature In Park Visitors: A Look At Structured And Unstructured Recreational Activities, Chelsea D. West 2010 University of Nebraska at Lincoln

Connection To Nature In Park Visitors: A Look At Structured And Unstructured Recreational Activities, Chelsea D. West

Dissertations & Theses in Natural Resources

There is evidence that park visitation is on the decline (Pergams & Zaradic, 2008) and if this is the case, and budgets decrease proportionately, there is a chance park land will be lost. Definitive explanations of the decline in park visits and time spent in nature are not available. In addition, there has been some discussion and research pertaining to the possible effects on people of not going into the natural environment and experiencing a connection with nature.

This study represents the first research known to focus on connectedness to nature and its relationship to structured and unstructured recreational activities. To ...


Water Current, Volume 42, No. 1, Winter 2010, 2010 University of Nebraska - Lincoln

Water Current, Volume 42, No. 1, Winter 2010

Water Current Newsletter

Meet the Faculty (Tala Awada and Cody Knutson)
Above Average Precipitation Causes Groundwater Level Rises
$3.1 million NSF Grant Funds Innovative Grad Education Program
From the Interim Director: Getting a Feel for the Job With Lots Ahead for the Water Center
Free Water and Resources Lectures Continue
Planning Continues for Platte Basin Tour
October River Basins Symposium and Law Conference
Feds Mull Regulating Drugs in Water
Sediments and Emerging Contaminants: On the Menu and in the Air
Watching Water Consumption
Improved Site Adds New Features
Featured Partner: Tern and Plover Conservation Partnership
Wastewater Treatment Education Helps Protect Nebraska’s ...


Feasibility Of Using 15N-Enriched Escherichia Coli As A Bacterial Tracer In The Cane Run/Royal Spring Basin, Kentucky, John G. Warden 2010 University of Kentucky

Feasibility Of Using 15N-Enriched Escherichia Coli As A Bacterial Tracer In The Cane Run/Royal Spring Basin, Kentucky, John G. Warden

University of Kentucky Master's Theses

A novel tracer method has used 15N to label Escherichia coli and track the transport of bacteria, a common contaminant, through karst aquifers. Use of this method could provide valuable insight into the movement of bacteria in aquifers, which would help improve remediation methods and strategies. A wild strain of E. coli was isolated from the Cane Run/Royal Spring basin in the Inner Bluegrass region of Kentucky. The strain was serotyped O-:H- and virulence testing showed the strain did not have virulence factors of E. coli commonly pathogenic to humans. Five karst microcosms were filled with sterilized ...


Reframing Climate Change As A Public Health Issue: An Exploratory Study Of Public Reactions, Edward W. Maibach, Matthew Nisbet, Paula Baldwin, Karen Akerlof, Guoqing Diao 2010 George Mason University

Reframing Climate Change As A Public Health Issue: An Exploratory Study Of Public Reactions, Edward W. Maibach, Matthew Nisbet, Paula Baldwin, Karen Akerlof, Guoqing Diao

Faculty Research Publications (All Departments)

Background: Climate change is taking a toll on human health, and some leaders in the public health community have urged their colleagues to give voice to its health implications. Previous research has shown that Americans are only dimly aware of the health implications of climate change, yet the literature on issue framing suggests that providing a novel frame - such as human health - may be potentially useful in enhancing public engagement. We conducted an exploratory study in the United States of people's reactions to a public health-framed short essay on climate change. Methods: U.S. adult respondents (n = 70), stratified ...


Terrestrial And Marine Geobiophysical Spatial Analysis And Modeling Of Phytoplankton And Nutrients In Haifa Bay, Israel, Sinaya Dayan 2010 Marshall University

Terrestrial And Marine Geobiophysical Spatial Analysis And Modeling Of Phytoplankton And Nutrients In Haifa Bay, Israel, Sinaya Dayan

Theses, Dissertations and Capstones

Haifa Bay, Israel, is considered one of the most polluted environments in the nation. The bay water is enriched with nutrients and shows elevated levels of phytoplankton biomass. This requires continuous data collection to monitor productivity. The objectives of these remote sensing geobiophysical models were to (1) create a terrestrial model component to identify sources for the elevated levels of nutrients in the bay, and (2) marine model component to validate remote sensing algorithms for the detection of Chlorophyll in an oceanic setting. Methods included Spatial Analysis, Principal Component Analysis, Unsupervised Classification, Map Algebra, Band Ratios, and Statistical Regression of ...


The Effect Of Dietary Supplement On Risk Of Infection In Community Based Patients With Type Two Diabetes Mellitus, Mamoon Ibrahim Abu Haltem 2010 United Arab Emirates University

The Effect Of Dietary Supplement On Risk Of Infection In Community Based Patients With Type Two Diabetes Mellitus, Mamoon Ibrahim Abu Haltem

Theses

Background: Type Two diabetes mellitus prevalence is increasing dramatically universally and locally. Diabetic patients have shown higher risk of infections and associated morbidity. Many factors contribute to this, including poor nutritional status of this population. The lack of evidence in this field inspired us to look at the relationship between the dietary supplements and risk of infection in these patients.

Objective: To measure the effect of dietary supplement on risk of infection in community based patients with type 2 diabetes mellitus.

Methods: Following informed written consent 100 diabetic patients have been randomly assigned to receive either an oral dose of ...


The Effect Of Visfatin And Adiponectin On Metabolic Parameters Of An Animal Model Of Type 2 Diabetes, Thuraya Saeed Ali AlShamisi 2010 United Arab Emirates University

The Effect Of Visfatin And Adiponectin On Metabolic Parameters Of An Animal Model Of Type 2 Diabetes, Thuraya Saeed Ali Alshamisi

Theses

Background: Diabetes mellitus (DM) is one of the most common exocrine disorders affecting more than 6% of the world’s population. The incidence and prevalence of this chronic disease are on the rise in many parts of the world including the Middle East. DM is caused by defective Insulin production, release and/or function. The causes and nature of abnormal insulin metabolism is less than clear. While defective insulin secretion is observed in type 1 diabetes, insulin resistance is predominant in type 2 diabetes, which affects more than 94% of the diabetic patients.

Materials and Methods: Rats between the age ...


Effect Of Various Heavy Metals On The Enzymatic Activity Of Bacterial Alkaline Phosphatase, Maithah Maktoom Salmeen Al Nuaimi 2010 United Arab Emirates University

Effect Of Various Heavy Metals On The Enzymatic Activity Of Bacterial Alkaline Phosphatase, Maithah Maktoom Salmeen Al Nuaimi

Theses

Soil is a natural resource that is utmost importance from an agricultural as well as environmental perspective. Good soil health not only helps improve the quality and yield of agriculture products, but is also important for recycling of significant amounts of organic biomass. However, pollution of soil by various pollutants, such as heavy metals, pesticides or petroleum hydrocarbons, can lead to serious environmental as well as biological effects. This pollution can directly harm animals and human beings, leach into drinking water source, damage plants and vegetation, as well as affect the endemic microorganisms and insects living in the soil.

Microorganisms ...


The Genetic Basis Of Familial Hypercholesterolemia In The United Arab Emirates, Shaikha Saif Mohamed Al Mazrooei 2010 United Arab Emirates University

The Genetic Basis Of Familial Hypercholesterolemia In The United Arab Emirates, Shaikha Saif Mohamed Al Mazrooei

Theses

No abstract provided.


The Prevalence Of Epstein Barr Virus In The Tonsils And Adenoids Of United Arab Emirates Nationals, Shamma Sultan Mohamed Al Dhaheri 2010 United Arab Emirates University

The Prevalence Of Epstein Barr Virus In The Tonsils And Adenoids Of United Arab Emirates Nationals, Shamma Sultan Mohamed Al Dhaheri

Theses

Although Epstein-Barr virus (EBV) is often found in human tonsils and adenoids, it remains to be precisely determined in what cells and microenvironment the virus is present. Although generally regarded as a B lymphotropic virus, EBV can infect non B-cells. The aim of this project is to determine the prevalence of EBV in the tonsils and adenoids of the United Arab Emirates (UAE) Nationals and to provide a basis for understanding the origin and biology of EBV -infected B and non-B cells, the immunophenotype of all EBV -infected cells in reactive tonsils was determined by subjecting tonsil and adenoid sections ...


Dimethylmercury Production In Freshwater Sediments, David C. Kelly 2010 Wright State University

Dimethylmercury Production In Freshwater Sediments, David C. Kelly

Browse all Theses and Dissertations

Dimethylmercury (DMHg) has been examined almost exclusively in marine environments to date, plays an uncertain role in the global cycling of Hg, and is produced by a currently unknown mechanism in natural systems. We examined DMHg production in microcosms containing 100 cm3 of freshwater sediment sampled from 3 wetlands and a lake near Dayton, Ohio. DMHg was produced from all sediments analyzed, and found that production is increased significantly by the addition of inorganic Hg from ~0.1pM to ~10pM, its production is unaffected by autoclaving the sediment, and organic carbon additions had no discernible effect on production. Its total ...


Conversion Of Carbon Dioxide And Hydrogen Into Methane In Bench-Scale Microcosms And Packed Column Reactors, Brian Alexander Congiu 2010 Wright State University

Conversion Of Carbon Dioxide And Hydrogen Into Methane In Bench-Scale Microcosms And Packed Column Reactors, Brian Alexander Congiu

Browse all Theses and Dissertations

Escalating energy demands, rising costs, and increasing awareness of the environmental impacts of current energy sources have created an immediate need for sustainable, alternative energy resources and innovative fuel technologies. It is believed that a potential carbon-neutral fuel source can be generated through the microbial production of methane gas by methanogenic archaea. Carbon dioxide captured from the atmosphere and renewable production of hydrogen can be used to support these microorganisms for the large-scale production of methane. Bench-scale investigations involving 160 mL serum bottle batch experiments and two 11L packed-column reactors were conducted to evaluate the feasibility and efficiency of microbial ...


Mercury Speciation In Temperate Tree Foliage, Melissa Danielle Tabatchnick 2010 Wright State University

Mercury Speciation In Temperate Tree Foliage, Melissa Danielle Tabatchnick

Browse all Theses and Dissertations

Cycling of mercury (Hg) and monomethylmercury (MMHg) in forest ecosystems can affect exposures of terrestrial and aquatic wildlife within the watershed. Litterfall has been posited to be a major source of MMHg and total Hg to the forest floor; however, the origin of MMHg associated with tree foliage is largely unknown. I tested the hypothesis that leaf MMHg would be controlled by root uptake and thereby proportional to levels in soil. Fresh leaves and associated soil samples were sampled from nine tree species (deciduous and coniferous) at 30 locations spanning a 1145 km2 area in southwest Ohio, a region presumed ...


Transport Through Georeservoirs: Spatial Entropy In Hydraulic Properties, And Temporal Entropy In Residence Time Distributions, Lumeng Huang 2010 Wright State University

Transport Through Georeservoirs: Spatial Entropy In Hydraulic Properties, And Temporal Entropy In Residence Time Distributions, Lumeng Huang

Browse all Theses and Dissertations

The general principle of maximum entropy can be used to guide the construction of flow and transport models parameters when are uncertain. The principle states that the model which maximizes the entropy should be chosen so that the full multiplicity or uncertainty is represented in the model outcomes.

In models for flow and transport through georeservoirs, the principle would commonly be applicable to the uncertainty in the model outcome for the time of travel through the system, in order to represent the full range of multiplicity in the distribution of residence times. Importantly, the model which maximizes the entropy in ...


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