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Effects Of Glacial Discharge On Kelp Bed Organisms In An Alaskan Subarctic Estuary, Tania Marie Sparkland

Marine Biology

Global climate warming is having large-scale, pronounced effects on the physical environment of Arctic and subarctic nearshore marine ecosystems, such as the widespread melting of glaciers. The purpose of this study was to determine how changing environmental conditions due to glacial melting affect subarctic kelp bed community structure and organism fitness. This study compared kelp bed community structure under disparate environmental conditions on a glacially-influenced and an oceanic shore in the same subarctic Alaskan estuary. Laboratory tests assessed the effects of varying salinity and irradiance on growth and physiological competence (as maximum quantum yield ( Fv/Fm)) of the dominant kelp, …

The Influence Of Habitat Complexity, Prey Quality, And Predator Avoidance On Sea Otter Resource Selection In Alaska, Nathan Lord Stewart

Marine Biology

The differential selection of habitat by animals is one of the fundamental relationships that enable species to coexist. Habitat selection may be among various discrete categories (e.g., mudflat, boulder field, or meadow) or among a continuous array of characteristics such as vegetation percent cover, benthic substrate size, substrate rugosity, distance to prey resources, or distance to suitable escape terrain from predation. Sea otters are particularly suitable for resource selection studies because they are capable of selecting a wide variety habitat types in response to prey availability, competition, and predation. In Alaska, sea otters associate with a range of habitats types …

Fine Particulate Matter Constituents Associated With Cardiovascular Hospitalizations And Mortality In New York City, Kazuhiko Ito, Robert Mathes, Zev Ross, Arthur Nádas, George Thurston, Thomas Matte

Publications and Research

Background Recent time-series studies have indicated that both cardiovascular disease (CVD)mortality and hospitalizations are associated with particulate matter (PM). However, seasonal patterns of PM associations with these outcomes are not consistent, and PM components responsible for these associations have not been determined. We investigated this issue in New York City (NYC), where PM originates from regional and local combustion sources. Objective In this study, we examined the role of particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5) and its key chemical components on both CVD hospitalizations and on mortality in NYC. Methods We analyzed daily deaths and emergency hospitalizations …

Contaminant Exposure And Associated Biological Responses In Southern Beaufort Sea Polar Bears, Katrina K. Knott

Biological Sciences

Concentrations of mercury (Hg) and polychlorinated biphenyls (PCBs) were examined in polar bear (Ursus marititnus) to assess variations among sex and age cohorts, and evaluate possible adverse impacts of combined toxicant exposures. Biomarkers of selenium (Se) status (whole blood and serum Se concentrations, glutathione peroxidase activity), and thyroid status (total and free concentrations of thyroxine and tri-iodothyronine) were examined in Southern Beaufort Sea (SBS) polar bears. Both Hg and PCBs tended to be greater in female than in male polar bears and likely related to the type and proportion of marine-based prey in their overall diet. Significant positive relationships between …

Genetic And Phenotypic Divergence Within And Between Cinnamon Teal (Anas Cyanoptera) And Blue-Winged Teal (A. Discors), Robert E. Wilson

Biological Sciences

Spatial heterogeneity in selection pressures can lead to extensive morphological variation and differences at functional genes between populations across a species' range without corresponding genetic variation at neutral loci. Divergent selection among populations may thus lead to intraspecific variation and in many cases speciation. Phenotypic and genetic structure within and between Cinnamon Teal (Anas cyanoptera) and the closely related Blue-winged Teal (A. discors) was assessed using body size measurements and neutral genetic markers in conjunction with a functional locus, hemoglobin. Cinnamon Teal are composed of five subspecies corresponding to distinct ecogeographic regions in North and South America. Subspecies and geographic …

Genetic Ancestry Modeling And Performance Association In The Alaskan Sled Dog, Heather Jay Huson

Biological Sciences

Alaskan sled dogs present us with the unique opportunity to study the development of a population of dogs produced from the selective breeding of high performance athletes. I establish that sled dogs are a genetically distinct population of dogs that segregate into two sub-groups based on their racing style of "sprint" or short distance and "distance" or long distance. The practice of interbreeding Alaskan sled dogs with various purebred dogs over the past century has allowed us to investigate the impact of these domestic breeds on the sled dog genome and their potential contribution to athletic performance. Here, I establish …

Postbreeding Ecology Of Shorebirds On The Arctic Coastal Plain Of Alaska, Audrey R. Taylor

Biological Sciences

Previous research on the Arctic Coastal Plain (ACP) of Alaska has shown that postbreeding shorebirds congregate at coastal sites prior to fall migration. Relatively little has been done to compare distribution, community characteristics, or behavior broadly across the ACP landscape, but this information is necessary to set the context for interpreting population demographics and setting conservation priorities. I collected data on distribution, species composition, phenology, and habitat use of postbreeding shorebirds in 2005--2007. I found that distribution of shorebirds across the ACP was not uniform: I identified persistent "hotspots" at Peard Bay, Pt. Barrow/Elson Lagoon, Cape Simpson, Smith Bay to …

Sources Of Variation In The Symbiotic Association Between Alnus And Frankia In Interior Alaska, Michael D. Anderson

Biological Sciences

Symbioses between plants and nitrogen (N) fixing bacteria are ecologically and economically important interactions with complex evolution and ecology. Theoretical and experimental studies suggest that host specificity and environmental variation are important determinants of both evolutionary and ecological patterns in such interactions, but detailed descriptions of these parameters in natural habitats are lacking for most N-fixing systems. The aim of this set of studies was to provide such information for the symbiosis between alder ( Alnus spp.) plants and Frankia bacteria in interior Alaska. Major objectives were to determine whether: 1) different Alnus species (A. tenuifolia and A. viridis ) …

Lake Area Change In Alaskan National Wildlife Refuges: Magnitude, Mechanisms, And Heterogeneity, Jennifer Roach

Biological Sciences

The objective of this dissertation was to estimate the magnitude and mechanisms of lake area change in Alaskan National Wildlife Refuges. An efficient and objective approach to classifying lake area from Landsat imagery was developed, tested, and used to estimate lake area trends at multiple spatial and temporal scales for ~23,000 lakes in ten study areas. Seven study areas had long-term declines in lake area and five study areas had recent declines. The mean rate of change across study areas was -1.07% per year for the long-term records and -0.80% per year for the recent records. The presence of net …

Arctic Alaskan Shrub Growth, Distribution, And Relationships To Landscape Processes And Climate During The 20th Century, Ken D. Tape

Biological Sciences

The primary change underway in the tundra of Arctic Alaska is the increase in air temperature and expansion of deciduous shrubs since 1980. I explored relationships between shrub expansion and relevant ecosystem properties such as climate, soil characteristics, erosion, and herbivory. Alnus viridis ssp. fruticosa (Siberian alder) shrubs located along streams, rock outcrops, or other features with active disturbance regimes showed a positive correlation between growth ring widths and March through July air temperature. Climate-growth relationships were much weaker for alder in adjacent tussock tundra. Additionally, tussock tundra sites had different vegetation composition, shallower thaw, lower mean annual ground temperature, …

Micro Scale Analysis Of Fluid Flow And Diffusion In Coarse Grained Porous Media, Walter Johannes Fourie

Engineering

X-ray computed tomography and finite element analysis were used to visualize the internal geometry of porous media and calculate the hydraulic conductivity and the diffusion of a dissolved species through the media. The results were compared to laboratory generated results. The calculated hydraulic conductivity showed good agreement with the laboratory results, over-predicting the laboratory results with only 12.5%. Comparison of the calculated results with the Kozeny-Carman equation showed that the Kozeny-Carman equation over-predicted the laboratory results between 62% and 740% depending on the formulation used. The tortuosity and specific surface area showed the highest correlation in predicting the difference between …

Physical Mechanisms For Variation In Pink Salmon (Oncorhynchus Gorbuscha) Survival Within The Upwelling And Downwelling Domains Of The Northeast Pacific, Sara Elizabeth Miller

Fisheries

Regional coastal conditions have a strong influence on juvenile salmon (genus Oncorhynchus) survival during their critical first months in the marine environment. Salmon survival has been thought to be favored within the downwelling domain if water column stabilities increase, whereas stability may have the opposite effect at lower latitudes. To explore this hypothesis at a local scale, we examined the relationship between stability and the characteristics of growth rate, condition, and marine survival of several stocks of pink salmon (O. gorbuscha) within Prince William Sound (PWS) and two water masses, Alaska Coastal Current and shelf, in the northern coastal Gulf …

Policy And Market Analysis Of World Dogfish Fisheries And An Evaluation Of The Feasibility Of A Dogfish Fishery In Waters Of Alaska, Usa, Jason R. Gasper

Fisheries

Spiny dogfish is a valuable commodity on the world market and has a global capture distribution. There are three chapters evaluating dogfish markets and fisheries in this dissertation; Chapter 2 evaluates the spatial distribution of dogfish in the Gulf of Alaska; Chapter 3 provides an overview of world markets and evaluates conditions that have led to a decline in dogfish product demand in Europe; and Chapter 4 uses the information from the previous 2 chapters to provide and policy and market overview of dogfish fisheries in Alaska. Results from this study provide a comprehensive world overview of the modern dogfish …

Nucleic Acid Ratios As An Index Of Growth And Nutritional Ecology In Pacific Cod (Gadus Macrocephalus), Walleye Pollock (Theragra Chalcogramma), And Pacific Herring (Clupea Pallasii ), Ashwin Sreenivasan

Fisheries

Pacific cod (Gadus macrocephalus), walleye pollock (Theragra chalcogramma), and Pacific herring (Clupea pallasii) are among the most ecologically and commercially important species in the North Pacific Ocean. In spite of their importance, little is known about larval and juvenile growth strategies in these fish. Since larval and juvenile fish growth may determine future growth, possibly affecting recruitment success, assessments of growth strategies might improve predictive growth models. Nucleic acid ratios (RNA/DNA) can have applications as a sensitive growth index in larval and juvenile Pacific cod, walleye pollock, and Pacific herring, and can potentially be used to determine growth responses and …

The Topographically Asymmetrical Alaska Range: Multiple Tectonic Drivers Through Space And Time, Jeffrey Benowitz

Geosciences

The topographically segmented, ~700 km long Alaska Range evolved over the last ~50 Ma in response to both far-field driving mechanisms and near-field boundary conditions. The eastern Alaska Range follows the curve of the Denali Fault strike-slip system, forming a large arc of high topography across southern Alaska. The majority of the topography in the eastern Alaska Range lies north of the Fault. A region of low topography separates the eastern Alaska Range from the central Alaska Range, where most of the high topography lies south of the Denali Fault. To the west, there is a restraining bend in the …

Analysis Of Morris Water Maze Data With Bayesian Statistical Methods, Maxym V. Myroshnychenko, Anton Westveld, Jefferson Kinney

Festival of Communities: UG Symposium (Posters)

Neuroscientists commonly use a Morris Water Maze to assess learning in rodents. In his kind of a maze, the subjects learn to swim toward a platform hidden in opaque water as they orient themselves according to the cues on the walls. This protocol presents a challenge to statistical analysis, because an artificial cut-off must be set for those experimental subjects that do not reach the platform so as they do not drown from exhaustion. This fact leads to the data being right censored. In our experimental data, which compares learning in rodents that have chemically induced symptoms of schizophrenia to …

Ethics Of Paid Gamete Donation, Kyle Dayton, Maeleen Witte

Festival of Communities: UG Symposium (Posters)

This presentation shows the standing ethical questions in the aspect of gamete donation, analyzes them, and contrasts them. This article primarily focuses on whether it is ethical to pay a donor for their gametes (sperm or egg). Within this presentation, we question whether donation should be purely altruistic and not motivated by incentives.

Should Primates Have Legal Rights?, Hannah Barten, Zhimin Chen

Festival of Communities: UG Symposium (Posters)

A primate having legal rights is a controversial topic these days. Many other countries around the world support the idea of great apes having legal rights, because we for one are one of the five great primates. Others do not support this trending topic as much as others. These types of people believe that great apes such as chimpanzees are superb testing animals for medical purposes, because of the fact that they are closely related to mankind. Organizations such as Great Ape Protection, work towards protecting the rights of these great apes since they cannot speak for themselves. In many …

Female Sexism, Tasha Choi, Sirikwan Pitalkwaltanakul

Festival of Communities: UG Symposium (Posters)

Sexism in the sciences is not just relevant to the sciences but in all fields of study. Woman are steadily on the rise, many going to college, and much more graduating with a degree in sciences and other male dominated fields. But despite the increase of female academic success, there are still fewer females in careers like science and professorship. Many factors contribute to sexism in the sciences, those factors being motherhood and family commitments, social interactions of female and male from early youth, social barriers in the field, and possible biological theories.

Intelligent Design And Its Place In The Classroom, Victor Trinh, Mekdelawit Mezgebu

Festival of Communities: UG Symposium (Posters)

Creationism, is the dominant belief held by the public. Evolution, on the other hand, is the competing theory of the mechanisms of creation. The recent dispute among the scientific and political field that has furthermore complicated the question of intelligent design being integrated into the curriculum of public schools is addressed here. We attempt to give both sides of the argument, along with analyzing the components of each theory. Intelligent design advocates are for the idea of accommodating what they have coined “intelligent design” into the classrooms of American schools. The opponents of intelligent design (evolution supporters); however, claim that …

The Effects Of Climate Change On Basic Animal Cell Functions, Michelle Fulbright, Andrew Andres

Festival of Communities: UG Symposium (Posters)

Increasing global temperatures during the 21st century may have detrimental effects on basic cell functions within ectothermal animals. This project aims to systematically examine the effects of climate change on secretory cargo localization through the analysis of Rab Proteins found in the model organism Drosophila melanogaster. Rab Proteins play an essential role in vesicular transport within the cell and can be genetically manipulated to monitor the biological consequences of global warming.

Sustainable Alternative To Non-Biological Nitrogen Fixation To Nitrate For Fertilizers, Patrick Freeze, Glenn Miller

Festival of Communities: UG Symposium (Posters)

Currently, the industrial method of nitrogen fixation for use in fertilizers (Haber- Bosch process [N2 (g) + 3 H2 (g) <--> 2 NH3 (g)]) is our main source of non-biological conversion of atmospheric nitrogen to ammonia. The proposed research experiment utilizes the catalytic mechanism of titanium dioxide which, in the presence of heat or sunlight, undergoes fixation of atmospheric nitrogen. This method of nitrate production could serve as a sustainable source of nitrogen for fertilizers. Variables in the experiment included the manipulation of thermal pressure, heat, and base addition to counteract hydrochloric acid production, a selflimiting byproduct.

Mathematical Analysis And Applications Of Logistic Differential Equation, Eva Arnold, Monika Neda

Festival of Communities: UG Symposium (Posters)

Logistic differential equation has a way to measure the proportionality of various resources with respect to time. This equation has been used in many research areas, such as, biology, medicine, psychology, economics, etc. A mathematical description, analysis and solution of the logistic type differential equation is studied. Besides the mathematical part, the poster will contain biological examples, graphs of the direction fields for different parameter settings and logistic plots for specific species population. The logistic growth function will also be applied to learning curves in area of psychology, as a rate at which performance improves.

Accumulation Of Polonium-210 In Different Species Of Fish In Lake Mead, Suraj Ghevarghese John, Shungmugam Nallaperumal, Vernon Hodge

Festival of Communities: UG Symposium (Posters)

Discovered by Pierre Curie and Marie Skłodowska-Curie in 1898, polonium is a chemical element with an atomic number of 84. This rare naturally occurring radioactive element is chemically similar to bismuth and tellurium, and forms in uranium ores. Polonium-210 is an naturally occurring radioactive element with a half-life of 138.376 days(1). This element is found in trace amounts in most organisms. Our research is focused on the accumulation of polonium-210 in fish that occupy in Lake Mead.

The sample species is chosen based on varying lake stratification (layers of the lake). This gives us a good idea of the difference …

Oral Presentation: Plant Genes And Drought Tolerance, Norris Lam

Festival of Communities: UG Symposium (Posters)

Research has shown that a gene from C3 xerophyte Larrea tridentata (creosote bush), LtWRKY21, is involved in pathways governing creosote bush’s high tolerance to environmental stress. By understanding the way in which creosote bush adapts to drought, crop plants can be engineered to be more drought tolerant during times of imminent global climate change. To study the underlying mechanisms of creosote bush drought response, the LtWRKY21 gene was mobilized into the model organism Arabidopsis thaliana. Chlorophyll degradation, cellular electrolyte leakage, and water content in leaves will serve as indicators of drought tolerance in LtWRKY21-transgenic A. thaliana after treatment in chemically …

Hipsec X-Ray Diffraction And Infrared Spectroscopy Studies On Energetic Materials Under Extreme Conditions, Mai Huong Bausch, Yu Liu

Festival of Communities: UG Symposium (Posters)

We conducted a series of experiments on the decompositions of the energetic materials NaBH4, NH3BH3, HMX, and RDX under different pressures using the x-ray diffraction (XRD) technique; we also studied the lesser known but high-performance explosive FOX-7’s behaviors under high pressures using the infrared spectroscopy (IR) technique. For the chemical decomposition of NaBH4 and NH3BH3 we discovered possible x-ray induced hydrogen gas generation; for the decomposition of HMX and RDX, we discovered that the decay rates of these two materials vary with pressure respectively; for the study of FOX-7’s high pressure behaviors we discovered potential phase changes and pressure induced …

Construction And Use Of A Direct Calorimeter To Estimate Energy Expenditure In Hibernators, Mark S. Burger, Frank Van Breukelen

Festival of Communities: UG Symposium (Posters)

Metabolic rates have traditionally been estimated through indirect calorimetry (gas exchange or respirometry) due to its ease and availability. Oxygen consumption neglects the contributions of anaerobic metabolism, while direct calorimetry (heat production) estimates both anaerobic and aerobic metabolism. Walsberg and Hoffman (2005) report anaerobic metabolism may be more important to small rodents than was previously thought. During the non-steady state of mammalian hibernation, we hypothesize that anaerobic processes may play an even greater role in fueling metabolism. To address this question, we constructed a very sensitive calorimeter that utilizes the Seebeck effect from a thermoelectric element (Peltier device). We describe …

Has Recent Climate Change Caused A Genetic Bottleneck In A Sierra Nevada Population Of The Bushy-Tailed Woodrat?, Mitchell Gritts, Angela D. Hornsby, Majorie D. Matocq

Festival of Communities: UG Symposium (Posters)

Many montane species respond to climate change by shifting their range upslope as temperatures at lower elevations increase. An elevation range shift causes a range contraction that may result in a population bottleneck. Joseph Grinnell surveyed the fauna along the Yosemite transect from 1914 to 1920. In 2003 Craig Moritz and his colleagues began to resurvey the Yosemite transect to assess the faunal change during a century of climate change. The bushy-tailed woodrat suffered severe range contraction and population bottleneck between the two surveys. I will use evolutionary models to determine if the population has suffered a genetic bottleneck.

The Release Of Calcium In Bacillus Anthracis Pathogenicity Methods, Natiera Magnuson, Manomita Patra Bhowmik, Maria Elena Reynaga, Ernesto Abel-Santos

Festival of Communities: UG Symposium (Posters)

Anthrax infection starts with germination of Bacillus anthracis spores in macrophages. Some bacteria, including B. anthracis, can sporulate in response to environmental stress, such as starvation. During germination, large concentrations of calcium ions are released from the B. anthracis spore. Calcium ions are hydrophilic secondary messengers, and may therefore interfere with detection of the spore by confusing the cell signaling pathways. We investigated calcium release on infected macrophage viability by replacing the calcium stored in B. anthracis spores for other cations via demineralization/remineralization. It was discovered that calcium ions typically out-performed other cations in germination of B. anthracis.

Luminescent Ionic Liquid Crystals Based On Stilbazolium Moieties, William Mccurdy, Pradip K. Bhowmik

Festival of Communities: UG Symposium (Posters)

Liquid crystals have become pivotally important to a variety of image displaying technologies. They have drawn much attention due to their ability to confer luminescent properties to a wide spectrum of image based devices. The purpose of this research is to describe a new methodology for an efficient synthesis of luminescent ionic liquid crystals including a discussion of their applications in the biological/medicinal sciences.