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2014 Abstracts

Optimizing the measurement of monomethylmercury in natural waters by direct ethylation

January 01, 2014 12:00 AM
The method currently used to measure monomethylmercury (MMHg) in natural waters involves a lengthy distillation step in order to remove certain ions and dissolved organic matter that have been reported to interfere with the subsequent reaction in which MMHg is ethylated. It has recently been reported that the analysis of MMHg in seawater by direct ethylation was successfully carried out, thus removing the day-long distillation. However, the effect of many potential interfering ions and compounds on this method have not been characterized, and it has not been tested for use in natural freshwaters or the hypersaline waters of the Great Salt Lake. Thus, these became the two goals of this project. We found that optimal ethylation conditions included buffering samples to pH 4.0-4.1, reducing the amount of sodium tetraethylborate, adding EDTA to complex interfering trace metals, and adding chloride to overcome interferences by thiols and organic matter. We have since employed this improved method to analyze MMHg in natural water samples from fresh and saline lakes, achieving > 90% MMHg spike recoveries without the use of distillation.

An insulating gasket for electrical measurements in a diamond anvil cell

January 01, 2014 12:00 AM
In my presentation, I will discuss the method of creating insulating gaskets for high pressure experiments using diamond anvil cells. In standard diamond anvil cell pressure experiments, metal gaskets are typically employed. However, in order to study the electric and magnetic properties of a sample without worrying about interference of the metal gasket itself, insulating gaskets are used. The insulating material needs to be ductile and yet hard enough to maintain a certain level of structure. Epoxy is ideal for ductility but is not hard enough to maintain a diamond indent under pressures generated by diamond anvil cells. When mixed with a diamond powder however, the mixture is both ductile and structurally sound. In this study we have modified the previous methods of insulating gasket preparation by addition of a metal sheet to increase the strength and ductility of the gasket. The part of the gasket that is metal can be used as an electrical lead to measure sample’s conductivity. In this design the mixture of diamond and epoxy is applied to a thin 100 micrometer metal sheet and a focused beam of high power IR laser is used to drill a hole in the gasket . I will describe the design of the optical path and the details of the gasket preparation and will present some of the gaskets that I have made.

Evolution of Burrowing Mayflies: Tusks be gone

January 01, 2014 12:00 AM
Ephemeroptera, commonly referred to as mayflies, are found throughout the world. Within the order of Ephemeroptera resides a superfamily, Ephemeridea, commonly called burrowing mayflies. This common name was acquired due to certain physical and behavior characteristics present as nymphs. Ephemeridea nymphs live in the silt of aquatic environments and have adaptations for burrowing which include strong legs, as well as mandibular tusks. One exception to this is the family Behningiidae, which burrow, but lack the commonly associated mandibular tusks. Morphological data supported Behningiidae as sister to the other tusked burrowing mayflies, indicating that first burrowing behavior evolved and was later followed by the development of tusks(McCafferty; 1975 and 2004). While morphological data provides important insights into the evolution and phylogeny of mayflies, the development of molecular phylogenetics offers new contributions when determining evolutionary relationships within this superfamily. Objective: The purpose of this study is to investigate the relationships of the families of burrowing mayflies in order to test the hypothesis of tusk evolution. Methods: The specimens were acquired from collection efforts and colleagues. For each specimen the following laboratory procedures were carried out: DNA extraction, gene amplification via polymerase chain reaction, visualization via gel electrophoresis, and DNA sequencing. The genes targeted for sequencing included 12S mitochondrial rDNA, 16S mitochondrial rDNA, 18S nuclear rDNA, 28S nuclear rDNA, H3 nuclear protein coding, and CO1 mitochondrial protein coding. Data was also acquired from Genbank in order to augment missing data. Taxon sampling consisted of around 20 ingroup and 5outgroup taxa. Phylogenetic relationships were estimated using Maximum Parsimony, Maximum Likelihood, and Baysian methods. Conclusion: The families Behningiidae, Potamanthidae, Palingeniidae were supported as monophyletic. Behningiidae nested well within the other burrowing families. Hence, tusks evolved and were subsequently lost in the family Behningiidae even though it retained the burrowing lifestyle in the nymph.

Nondestructive Isolation of Forensic Analytes with Ionic Liquids

January 01, 2014 12:00 AM
New methods aimed at forensic analysis of sensitive, minute samples are critical to the intelligence community. In particular, successful extraction of dyes from materials found at crime scenes will provide innumerable benefits for matching, identifying, and finding origins of these materials and dyes. Current methods of isolating components of samples by their unique chemical properties are lengthy and often destroy important forensic evidence. Ionic liquids possess the necessary chemical properties to ensure efficient extractions, while maintaining the forensic signatures of the original materials. They also provide a one-pot approach that avoids intermediate species and increases analyte yield while extracting and separating constituents in a more efficient manner. By combining traceable dyes with an ionic liquid, the versatility of single-component extraction-separation-identification was demonstrated. Analysis using absorption and fluorescence spectroscopy validated complete extraction and recovery of trace analytes. Following extraction and isolation, identification by infrared spectroscopy has provided evidence of preserved quality and complete separation of material and dye. This novel approach to forensic analysis is advantageous particularly when sample sizes are extremely limited, but it can be readily scaled to larger applications. Developing a simple and affordable method of achieving specific molecular interactions provides a solution for often unidentifiable evidence in crimes. Harnessing the versatility of ionic liquids in a high-yielding recovery and efficient single-pot methods will enhance forensic abilities for the intelligence community and forensic investigators.

Methods to decrease error in conductivity measurements of highly disordered materials

January 01, 2014 12:00 AM
By developing a low-noise, high-voltage battery power supply, system noise has been reduced, increasing accuracy of conductivity measurements of highly disordered insulating materials. The method involves a simple parallel plate capacitor setup with the sample sandwiched between electrodes, a voltage potential applied to one electrode, and a measurement device applied to the back electrode measuring current. Previous methods involved use of a commercial power supply with a claimed low noise and high linearity, but with a low AC output ripple. At high voltages (1000 V), however, the noise became apparent in the readings and an unacceptable uncertainty was introduced in our precision conductivity measurements. Through the use of a stable dc battery high-voltage power supply, we were able to reduce noise in current measurements and achieve a more accurate measurement of conductivity for various samples.

Mode transitions in strings with an abrupt change in mass density

January 01, 2014 12:00 AM
Previous research with bottle-shaped thermoacoustic prime movers has revealed hysteresis with transitions to higher modes as the cavity length is varied. A string with an abrupt change in mass density was studied to investigate potentially similar behavior. Three base guitar strings were studied at three different tensions with weights of 25, 30, and 35 lbs. Each string consisted of a “thin side” that was stripped to the stainless steel core and a “thick side” with an outer wrapping of nickel around the core. The strings studied had diameters of 0.65, 0.45, and 0.50 mm on the thin side and 2.14, 1.31, and 1.24 mm on the thick side, respectively. An anchor was attached on one end of a short board with a pulley at the other for hanging the weight. The end of the thick side of the string was attached to the anchor, and the string was guided over the pulley, with the change in mass density occurring approximately 12 cm from the pulley. Measurements were taken after placing a glass jar under the thick end of the string, between 42 cm and the position of the change in mass density, in 3-cm steps. The string was plucked and the dominant frequency was recorded with a microphone at each location. Frequency data is generally consistent with a solution to a 1D wave equation. Preliminary results indicate mode transitions occurring for all strings, with several hysteresis region candidates.

Correlation analysis of military aircraft jet noise

January 01, 2014 12:00 AM
Correlation analysis is useful in extracting spatiotemporal relationships between signals and can be used to examine features of near-field jet noise for source properties. Characteristic correlation envelopes determined by Harker et al. [JASA 133, EL458 (2013)] can be used to relate correlation lengths to fine and large-scale turbulent structures. As an extension, cross-correlation shows spatial variation in jet noise and further reveals the transition between short (fine-scale) and long (large-scale) correlation lengths. These analyses are applied to a military jet dataset of a ground based linear microphone array positioned 11.6 m from the jet axis. Correlation analyses over multiple engine conditions and observation directions are reported. In particular, a maximum correlation coefficient greater than 0.5 exists over a range spanning multiple wavelengths in the region of greatest overall sound pressure level at military power. [Work supported by ONR.]

Analysis of Untriggered Small Events in the HAWC Telescope

January 01, 2014 12:00 AM
Current software in the High Altitude Water Cherenkov (HAWC) Telescope data collection system only triggers saving of events that pass a specified number of hits and energy. Our analysis of the untriggered (and unsaved) data will identify the number of potentially significant events that are bypassed by the existing software. By the application of a sorting function onto current Monte Carlo generated data, we can categorize incoming events into various types of particles, primarily muons, while also filtering out randomized noise from the photomultiplier tubes used in HAWC. Due to the relatively low rate and energy of the photomultiplier tube noise, many of the significant events for the untriggered set are potential useful particles. Our triggering algorithm, based on the energy, timing and saturation of the tanks is primarily focused on separating muons from the bulk of data. These raw rate data for small events are a relatively unexplored area for HAWC and measurements can be useful for a variety of calibration tasks for the telescope. They can be useful for understanding the impact of the atmosphere on the telescope’s data collection, as well as the triggering of the photomultiplier tubes through secondary sources. This untriggered data can also be used in a variety of useful forms not directly related to HAWC’s primary usage goals, primarily solar physics. Due to the relatively low energy and hit count from solar events, most of the data are thrown away by the triggering algorithm.

Evaluation of potential impact of tar sands mining on the integrity of groundwater quality in PR Spring, Uinta Basin, Utah

January 01, 2014 12:00 AM
Groundwater in the western United States is a limited and important resource for agriculture, industry, and residents alike. Knowing the movement of groundwater is critical to understanding the potential of groundwater contamination from human activities. While groundwater flow is difficult to quantify, it typically recharges in high elevation and discharges towards lower elevation. The first commercially-approved tar sands mine in eastern Utah is located on a ridgetop in the PR Spring area within the high plateaus on the south rim of the Uinta Basin. To evaluate the potential of groundwater contamination due to tar sands mining a study was conducted to understand groundwater flow in the PR Spring area, specifically the canyon directly south of the tar sands mine called Main Canyon. Water samples were taken from four groundwater springs at elevations ranging from 7040 to 8040 ft in or near Main Canyon. Water quality measurements taken in the field showed that the lower springs exhibited higher conductivity (900 vs. 636 μS/cm) and lower dissolved oxygen (30% vs. 88% saturation) than the higher elevation springs. This suggests that the lower springs have had a greater amount of water-rock interaction and so are chemically more evolved than the springs at higher elevations. SF6 age dating indicated that the high elevation springs are younger than the lower elevation springs, 5.5 vs. 16.0 years since recharge respectively. The field parameters and SF6 age data all indicate that higher elevation springs are younger and less chemically evolved than the water at lower elevations. This indicates that the springs in Main Canyon are sourced from local recharge at the ridgetops. Given these findings the tar sands mine should consider taking preventative measures to protect groundwater resources.

Protein phosphatase (PP) 1 and PP2B do not contribute to palmitate-induced disruption of eNOS enzyme function.

January 01, 2014 12:00 AM
Cardiovascular complications are more prevalent in patients with diet-induced obesity and type 2 diabetes. Both of these conditions are associated with elevated levels of free fatty acids (FFAs). Elevated FFAs might precipitate cardiovascular complications by disrupting endothelial nitric oxide (NO) synthase (eNOS) enzyme function. The physiologically abundant saturated FFA palmitate decreases eNOS phosphorylation at serine 1177 (p-eNOS S1177) in a ceramide and protein-phosphatase 2A (PP2A) -dependent manner. p-eNOS S1177 is a positive regulatory site on the eNOS enzyme. As such, p-eNOS S1177 to total eNOS can be used as an estimate of eNOS enzyme function. We sought to determine the extent to which two other phosphatases that are abundant in the cytosol i.e., protein phosphatase 1 (PP1) and protein phosphatase 2B (PP2B) might contribute to palmitate-induced reductions in p-eNOS S1177 to total eNOS. Bovine aortic endothelial cells (BAECs) were treated for 3 hours with 500 uM palmitate or vehicle in the absence and presence of the PP1 inhibitor tautomycin (3 uM). p-eNOS S1177 to total eNOS was assessed using immunoblotting procedures. Palmitate-induced reductions (30±3%, p<0.05, n=3) in p-eNOS to total eNOS were similar in the absence and presence of tautomycin. These data indicate that PP1 does not contribute to palmitate-induced disruption of eNOS enzyme function. Next, BAECs were treated for 3 hours with 500 uM palmitate or vehicle in the absence and presence of the PP2B inhibitor cyclosporine (100nM). Palmitate-induced reductions (31±4%, p<0.05, n=3) in p-eNOS to total eNOS were similar in the absence and presence of cyclosporine. Taken together, these data suggest that neither PP1 nor PP2B contribute to palmitate-induced reductions in p-eNOS S1177 to total eNOS.

The Use of ArcGIS and Shallow Groundwater Monitoring for Stormwater and Irrigation Management with a High Water Table, Springville, Utah

January 01, 2014 12:00 AM
Springville, Utah, is known for its high water table and many freshwater wetlands and springs, which gave rise to the name of the city. Flooding of barns is a common problem among farmers in western Springville, which is just east of Utah Lake. These frequent barn floods are anecdotally linked to high-intensity precipitation events and the common use of flood irrigation. The objective of this study is to determine the cause of barn flooding and to make recommendations for mitigation of barn flooding for individual farmers with whom we are working in this area. The objective is being addressed first by using ArcGIS to determine the watershed of each barn and the NRCS (Natural Resource Conservation Service) Web Soil Survey to map hydrologic soil groups within each watershed. Results from the larger-scale Web Soil Survey will be supplemented with measurements of soil hydraulic conductivity using the SoilMoisture Equipment Model 2800K1 Guelph Permeameter. The above data will be used in the NRCS Curve Number Method to estimate the volume of surface runoff expected in a 100-year 24-hour precipitation event. The objective is also being addressed by installing shallow, hand-augured wells for monitoring the depth to the water table during high-intensity precipitation events and flood irrigation events. The results will be used to develop recommendations for a combination of (1) installation of French drains for diversion of stormwater (2) modification of current irrigation methods (3) pumping and diversion of groundwater. Results and specific recommendations for individual farmers will be presented at the meeting.

Wavelength Detection from Filtered Photodiodes

January 01, 2014 12:00 AM
Filtered photodiodes show potential as inexpensive laser wavelength meter. Photocurrents are measured digitally. The photocurrent is digitized using externally controlled integration times to achieve the highest precision possible from the digital to analog converters on the photosensor chip. Using an algorithm we’ve developed and calibrated intensity curves, we can precisely calculate wavelength from the output of the different photodiodes. Limitations due to etaloning from reflections off of the surfaces of the filters were analyzed and effectively mitigated, allowing the device to achieve high precision with a stability of 0.102 nm over several hours.

Characterization of undocumented bonneville shorelines with evidence of possible tsunamis

January 01, 2014 12:00 AM
There are many undocumented shorelines seen in Utah. As many as 30+ shorelines have been identified along the edges of the basin throughout the state. The purpose of this study is to characterize undocumented shorelines and identify potential evidence for tsunamis that might have occurred in Lake Bonneville thousands of years ago in areas such as Little Mountain, Stansbury Island, and Promontory Point, Utah. Lake Bonneville existed 32-10K years ago and was influenced by the Wasatch fault which was active as early as the Miocene. Scarps of this age are common and range between 15-20 feet in height (Machette, Personius, Nelson, Schwartz, Lund 1991; Dinter, Pechman, 2004a and 2004b). Several faults beneath Lake Bonneville could have produced tsunamis. The more water that is displaced the greater the tsunami will become and leave a greater impact onshore (Dutykh and Dias 2009). The East Great Salt Lake fault cuts NS across Bear River Bay east of Promontory Range. This fault line is an excellent candidate for causing a tsunami during the Lake Bonneville highstand because it is beneath the Great Salt Lake meaning it would have uplifted the entire water column of Lake Bonneville and since it is also close to the Promontory Range, it is likely it would leave tsunamite evidence along the shore. The fault rupture interval is between 3,000 and 3,500 years meaning fault ruptures could produce a tsunami during the lake’s high stand. Tsunamite is the term used for deposits related to tsunamis. The tsunamite features found along the shorelines will be similar to sedimentary features such as normally graded sand, mudstone clasts, and other gravel deposits that are out of place with the known shorelines (Shanmugam 2006). This is a unique opportunity to discover ancient tsunami evidence in Utah, a topic that has yet to be pursued.

Bio-Inspired Molecular Manganese-Calcium Catalysts for Water Oxidation

January 01, 2014 12:00 AM
Increasing concerns on the anthropogenic climate change, rising global energy demands, and diminishing fossil fuels have urged the search of alternative carbon-neutral and sustainable energy resources, among which solar energy stands out as the most promising target since it is the largest exploitable resource. However, its nature of diurnal variation, intermittence, and unequal distribution requires efficient and cost-effective capture, conversion, and storage. Generation of chemical fuels, such as hydrogen, from solar energy input represents an appealing approach to meet this goal. An ideal scheme would tap hydrogen from the splitting of water with concomitant evolution of oxygen. Due to the nature of the four-proton and four-electron process, water oxidation is the bottle neck of the overall water splitting process. Nature catalyzes water oxidation using an oxygen evolving complex (OEC) in photosystem II. This project aims at mimicking the OEC to prepare and investigate bimetallic Mn-Ca catalysts for water oxidation catalysis. Calcium has been reported to be critical in water oxidation by OEC, however its functional role has not been well studied. By positioning a calcium atom in the second coordination sphere of manganese in molecular scaffolds, we are able to systematically study the functional role of calcium at the molecular level. Our project will prompt the development of water oxidation catalysis and benefit artificial photosynthesis at large.

Melting Glaciers: A source of mercury and other trace elements to high elevation ecosystems at Grand Teton National Park?

January 01, 2014 12:00 AM
Wyoming the second most glaciated state in the lower 48 United States has seen drastic changes in the size of its glaciers. Glaciers in high elevation ecosystems of Grand Teton National Park are not anywhere near to the size that they were 100 years ago. The glaciers continue to decrease in size every day. As the environment changes the glaciers change in size and can be affected by many factors in the environment. Deposition of particulate matter from the atmosphere into the glaciers occurs as pollution is becoming worse and more common. Studies done throughout the world have shown that glaciers can act as a source for mercury and other trace metal elements in high elevation ecosystems. Through the assistance of the UW-NPS Research Station Dr. Greg Carling of BYU and his team of graduate and undergraduate assistants retrieved 100 glacial melt water samples from the Middle Teton, and Teepee Glaciers and stream sites in Garnet Canyon, and from the Teton Glacier in the Glacier Gulch area. In the data analysis completed up until this point, concentrations of various trace elements have found in sample sites in close proximity to the Middle and Teton glaciers on the glacial moraine. We hypothesize that these glaciers act as a source for mercury and trace elements that can then be transported to lower elevation ecosystems within the Greater Yellowstone Ecosystem.

Trace element concentrations showing signs of urbanization along the Provo River, Utah

January 01, 2014 12:00 AM
The Provo River provides the opportunity to study three systems from low to high anthropogenic activity. Its headwaters are in an undeveloped area of the Uinta Mountains. The river then moves into a valley that is developing from an agricultural to an urban system. The lower portion of the river moves into the urbanized Utah Valley. These systems give the ability to study the changes in trace element chemistry from a variety of sources. Trace element data were collected during the 2013 water year including the spring snow melt. Correlation was analyzed among the different trace elements using multivariate statistics in order to discover trace element sources. The element loads were calculated using USGS Load Estimator (LOADEST) software. The study has implications involving the drinking water of >2 million people in the Utah and Salt Lake valleys and the changes that the shift from agriculture to urban is causing.

How many class ii wells present a risk for induced seismicity?

January 01, 2014 12:00 AM
We examine the number and location of Class II wells in the central U.S. to constrain future work on the potential for induced seismicity. The EPA, state oil & gas commissions, scientific papers, and media stories frequently state that there are ~140-160 k Class II wells. Excluding California, we expected to find approximately 120 k wells; but instead found ~ 82 k active injectors in the available databases. State datasets vary in accessibility, availability, and content of well data. Lack of digitized well data also limited our online search, and several states require FOIA requests to be filed. State databases with poor searching and sorting functions further complicated data mining, requiring a well-by-well search, and for several states, well locations and injections were difficult to determine. Common discrepancies between EPA well totals and state database totals appear to be due to counting of plugged and abandoned wells, and wells that are permitted but not in use. No data has been retrieved for about 1,600 wells on tribal lands and Indian Country, and several states would not provide “confidential” well data. Of the active injectors, at least 55 k wells inject into producing, pressure-depleting oil and gas formations and are less likely to generate damaging earthquakes. Of the ~ 16 k non-EOR wells, we found 3,400 wells that inject at depths > 1.8 km, where most M > 3.0 midcontinent earthquakes occur. We will present examples of data from several states, that show the locations and depths of injectors, earthquakes, depth to basement, and we will provide an overview of the public file sharing system of the data. We will search for correlations between the depth of injection, the number of injection wells, recent seismic activity, the nature of the subsurface geology, and regional stresses.

Histone modifications are altered in the renal cortex of ventilated preterm lambs

January 01, 2014 12:00 AM
Objectives: Histone covalent modifications influence regulation of gene expression. Changes in histone covalent modifications are triggered by abrupt changes in environment, such as preterm birth followed by mechanical ventilation (MV). Whether histone modifications also occur in the kidney of chronically ventilated preterm lambs is not known. We hypothesized that ventilation of preterm lambs affects histone modification in kidneys.

Source of Elevated Free Carbon Dioxide Levels at the Springville State Fish Hatchery, Springville, Utah

January 01, 2014 12:00 AM
DWR operates the Springville Fish Hatchery raises rainbow trout for stocking lakes and ponds. Since February 2011 the hatchery has observed excessive physical activity among the trout, including jumping out of raceways onto the concrete walkways. Excessive physical activity can result from free carbon dioxide levels above 10 ppm and free carbon dioxide levels in the hatchery water have been measured as high as 17 ppm. They have added some treatment processes before it enters the hatchery and greatly reduced the food intake of the trout, which increase costs and reduce production. This has reduced free carbon dioxide levels to only 15 ppm. The objective of this study is to determine the source of elevated free carbon dioxide and recommend solutions for the problem. The water source for the hatchery is a shallow pond, which is fed by 16 springs, both warm and cold. The objective is being addressed by measuring discharge from each spring and collecting water samples for measurement of free carbon dioxide in addition to other common stressors of rainbow trout. Free carbon dioxide, temperature, pH, electrical conductivity and dissolved oxygen are being measured on-site, while hardness, nitrite, ammonia, copper, iron and zinc are being measured. Free carbon dioxide levels at some warm springs have been measured as high as 25 ppm. Mixing calculations will be carried out to determine whether the discharge and water quality of each spring is consistent with the water quality currently entering the hatchery and whether the removal of one or more springs would result in sufficient water within the acceptable ranges for rainbow trout. If calculations estimate free carbon dioxide significantly lower than the measured free carbon dioxide in the water entering the hatchery, it is possible that additional elevated free carbon dioxide results from the decay of organic matter.

Lyman-alpha Emission as a Probe of Galaxy Environments

January 01, 2014 12:00 AM
We study the effect of the circum-galactic gas environment on the observed Lyman-alpha emission from Lyman-alpha emitting galaxies. These galaxies are primarily high-redshift star-forming galaxies that are important in understanding both galaxy and universe evolution. The Lyman-alpha photons emitted from these galaxies should hold valuable clues about the general environmental properties (such as gas velocity, density, and distribution) around galaxies, since the photons can be strongly affected and scattered by the neutral hydrogen atoms that make up the majority of the gas. However, explaining exactly how a galaxy’s environment affects its Lyman-alpha emission is very complex and currently cannot be predicted with complete certainty — every time a Lyman-alpha photon interacts with a hydrogen atom, its direction and frequency are changed, which in turn affects how far it will travel before the next interaction. We study the environmental effects on Lyman-alpha emission properties by applying Monte Carlo Lyman-alpha radiative transfer modeling to simple analytic models and find an important role of the anisotropic distribution of gas in determining the observed photometric and spectral properties of Lyman-alpha emission. We further perform a detailed investigation by applying the radiative transfer modeling to realistic star-forming galaxies in high-resolution cosmological galaxy formation simulation. From our analysis so far, we find the Lyman-alpha emission from the models shows a strong dependence on viewing angle, as well as correlations between observed spectral features and environmental conditions. We plan to model and analyze a large sample of simulated galaxies to better describe and statistically quantify the above dependence and correlations. Our study will lead to a better understanding of the effects galaxy environment on the observed Lyman-alpha emission and in turn provide a theoretical guide on how to use observed Lyman-alpha emission to learn about the environments of star-forming galaxies and hence galaxy formation and evolution.

Structural health monitoring of natural arches in the Moab area

January 01, 2014 12:00 AM
We evaluated the ambient noise wavefield of select arches in the Moab area as a means to assess changes in their structural health over time. Our measurements revealed that the fundamental frequency of vibration at Mesa Arch and Corona Arch are both in the range of 3 Hz, while other spectral peaks are likely related to higher-order vibrational modes. We use numerical modeling for modal analysis in an attempt to predict and visualize the various modes of vibration and their frequency Resonant frequencies are projected to change with snow or rain loading or after a strong earthquake. By monitoring resonant frequencies over time and under various environmental conditions, our goal is to detect reversible and/or irreversible changes that may accompany damage of these arches.

Preventing Mode-hops in Extended-cavity Diode Lasers

January 01, 2014 12:00 AM
Extended-cavity diode lasers are important tools in scientific research. Current extended-cavity diode laser systems will change frequency unpredictably while operating, requiring extensive effort to tune them back to the right frequency. We seek to implement a novel method of extended-cavity diode laser control that adds an extra control system to prevent these unpredictable changes.

Controlled Zinc Oxide Hexagonal Prism Formation with Ethanol Amines

January 01, 2014 12:00 AM
A method of forming zinc oxide (ZnO) single crystal hexagonal prisms is derived from a standard sol-gel method. The new synthesis requires water, zinc acetate, and diethanol amine (DEA) to create a zinc hydroxide/zinc hydroxide acetate gel, which forms single crystal hexagonal prisms upon heating. Characterization of the gel was done by XRD as well as by XRD high temperature chamber (HTK) to determine the role of temperature in prism formation. SEM images showed hexagonal prisms were of uniform size (approx. 0.5 — 2 µm). TEM and electron diffraction images showed a change from randomly oriented particles to an ordered single crystal after heating. Ethanol amines, heating of the gel, and the zinc acetate salt proved to be critical to prism formation.

Use of the Manning Equation to Estimate Stream Discharge through Natural Slot Canyons and Artificial Slots

January 01, 2014 12:00 AM
Stream discharge through narrow, deep slot canyons can be a major source of groundwater recharge in the arid Southwest. Various state and federal agencies use the empirical Manning Equation to predict the discharge through artificial slots created for diversion of rivers around coal mines. However, it is not obvious that the Manning Equation could be applied to slot canyons or artificial slots as the data base used for development of the Manning Equation did not include either natural streams or artificial structures for which most of the friction occurs along the sides of the channel. The objective of this research is to develop an empirical formula for estimating the Manning roughness coefficient for flow through narrow, deep slots. The objective is being addressed by measuring stream discharge through natural slot canyons in southern Utah that are fed by perennial streams, springs or dam outlets. Based on measurements at ten sites along eight streams, the best estimate for the Manning roughness coefficient is n = 0.873nJ exp(5.108A/w2) where A is stream cross-sectional area, w is stream width, and nJ = 0.39S0.38R-0.16 is the roughness coefficient estimated by Jarrett (1984) for high-gradient streams, in which S is slope of the stream bed and R is hydraulic radius (ft). The new formula estimates stream discharge with a mean accuracy of 44%. On the other hand, Jarrett’s (1984) formula underestimates stream discharge by 1-2 orders of magnitude for aspect ratios A/w2 in the range 0.6-0.7. The new formula will be refined by additional measurements on slot canyons, artificial diversions, and a laboratory hydraulics bench. It is hoped that the new formula will lead to a more realistic design for artificial slot diversions.

Utilizing Low-cost NIR Imaging Systems in Medical Physics

January 01, 2014 12:00 AM
Infrared Thermography (IRT) has become popular in the medical field for various applications and procedures. One such application involves the use of IRT in the active detection of skin lesions and neoplasms. More specifically, medical professionals are using IRT as a non-invasive method for the early detection of harmful lesions, such as melanoma.

Synthesis, Analysis, and Biological Activity of Novel Organoarsenic Products

January 01, 2014 12:00 AM
Organoarsenic are compounds containing carbon and arsenic. These compounds have been shown to have biological activity and pharmaceutical properties, and some organoarsenic compounds have even displayed potential for aiding in current medical problems up to and including possibilities as anticancer agents. Currently relatively little research is being done on organoarsenic compounds by the pharmaceutical community due to current views from the media based largely upon the toxicity of their inorganic arsenic counterparts (inorganic compounds are compounds not containing carbon), organoarsenic compounds however have significantly toxicity. Also, like with any medicine, toxicity depends predominately upon concentration, and given a high enough concentration organoarsenic compounds would logically follow the same trend. Synthesis of a large variety of novel organoarsenic compounds has been found via a reaction involving a variety of aldehydes or ketones and 2-(Dichloroarsino)benzaminium chloride. Research will focus on synthesis, isolation, and characterization of a library of organoarsenic compounds and then determine their respective biological activities. Synthesis will determine mechanistic requirements of said reaction and will be done to produce a diverse selection of organoarsenic compounds. Compounds will be isolated through precipitation of product and vacuum filtration of formed product. Structure will be determined through IR, NMR, and Gas Chromatography/ Mass Spectrometry, and through X-ray crystallography. Biological activity is suspected with potential for testing via a Kirby-Bauer Disc treatment. It is hypothesized that novel organoarsenic products will be formed by reaction of 2-(Dichloroarsino)benzaminium chloride with all carbonyl compounds containing an alpha carbon with at least one proton used, and that compounds synthesized will inhibit bacterial growth.

Use of Phage and Vancomycin Treatments Against Staphylococcus aureus Biofilms

January 01, 2014 12:00 AM
Implant devices such as orthopedic, dental, and cochlear implants are commonly utilized as part of many medical treatments. However, these foreign objects are susceptible to bacterial contamination, thereby putting the host at risk of an infection that is challenging to eliminate due to biofilm formation. Biofilms are formed when a bacterial cell adheres to and colonizes such metal or plastic surfaces. The cells aggregate to form and embed themselves in a thick and protective polysaccharide matrix, making biofilms resistant to many antibiotic treatments.

Precise External Timer

January 01, 2014 12:00 AM
In the construction of various sensors in the lab, highly accurate integration times are required. It is advantageous to have a precise external timer to run the circuitry contained in the sensor. By taking a signal in the range of megahertz down to hertz or milihertz range, it is possible to control the start and stop times for circuits. Overall this means that every time a measurement is taken it represents the same length of time.

Gallai Colorings of Complete Graphs with Applications to the Theory of S-rings

January 01, 2014 12:00 AM
A Gallai coloring of the complete graph on n vertices is an edge coloring such that no triangle has edges of three different colors.

Models for Dementia Diagnoses with Distributed Learning

January 01, 2014 12:00 AM
Dementia is a clinical syndrome characterized by an overall loss of cognitive ability. There are multiple forms of dementia with various causes and various impacts on the suffering individuals. Accurate diagnosis is essential to effective intervention and treatment. Currently, clinicians lack a biological marker that definitively distinguishes the different forms of dementia. Hence, they rely on physical exams, neuropsychological tests, and patient report to provide a diagnosis. Recent advances in brain imaging make it possible to obtain detailed maps of brain activity, which in turn may offer insight into many conditions such as dementia. Developing a predictive model from patient data, including brain scans, would greatly enhance the ability of clinicians to provide accurate diagnosis, and hence appropriate treatment, to their patients. Doing so, however, is not trivial as patient data is heterogeneously and non-uniformly distributed across sites, where some sites have far more data than others and calibration varies among scanners used. We report on the development of novel predictive models based on distributed learning for the effective diagnosis of dementia.

Space Filling Curves and Their Applications With Metamaterials

January 01, 2014 12:00 AM
The popularity of metamaterials has exploded with in the last decade. Metamaterials are materials that exhibit interesting properties not found in nature; one of the most widely known features being a negative refractive index. Metamaterials are composites different types of materials that give them their interesting properties. In addition to being composed of several element types, metamaterials also contain certain inclusions that influence their electromagnetic properties. Among these are space filling curves. Space filling curves are curves that are entirely contained within a specific area and yet can become infinitely long. In my research I investigated the properties of space filling curves and their application/benefit to the research surrounding metamaterials, specifically metamaterial antennas.

The stability of a semi implicit numerical scheme for a competition model arising in Math Biology

January 01, 2014 12:00 AM
We study the Lotka-Volterra competition model. This model can be applied to Math Biology. We propose a Semi-Implicit numerical scheme, which guarantees that the populations are always positive. Also we prove that the numerical scheme is uniquely solvable, and is unconditionally stable.

Higher Dimensional Smooth Data Interpolation Techniques from Computational Geometry

January 01, 2014 12:00 AM
A typical problem in numerical analysis is finding a smooth interpolation of a given data set such that information at extended positions can be evaluated. When extended to higher dimensions, there are few such algorithms available for practical use. Drawing from techniques used in geometric modeling we developed a practical algorithm with improved complexity by implementing the techniques in a query model as part of a MATLAB software package. From initial input data the algorithm builds a d-dimensional cell complex using Delaunay triangulation. Each cell has an associated interpolation function that satisfies Lipschitz continuity for each new point. During query time the user specifies a query point and the algorithm returns the interpolated function value. To reduce complexity related to point location within the cell complex, we implemented a binary tree search based on hyperplane decision criteria. Efficiency analysis completed using benchmark data sets indicated that the decision tree algorithm improved the efficiency from O(N) to O(N log N). This algorithm is the first of its kind that can be used on actual data sets and is the first implemented as a MATLAB package.

Examining the rainbow effect of metamaterial droplets

January 01, 2014 12:00 AM
Rainbow is an optical phenomenon created by reflection and refraction of light at the boundaries of water droplets. Descartes was the first to provide a geometric explanation for the optics of the rainbow. We use Descartes’ method to examine if rainbow effect is possible with metamaterial droplets. Metamaterials are artificial materials whose permittivity and permeability can be simultaneously negative hence, giving them negative index of refraction for certain frequencies. The recent extraordinary level of output in the field of metamaterials has resulted in examinations of applications of these substances to a variety of fields, including the arrow of time and cloaking. Many applications of metamaterials can create physical effects that were previously assumed impossible. In this study we have considered that our hypothetical droplet has negative refractive index for visible band of the electromagnetic spectrum. We also examine the effect of using composite metamaterial droplets.

Numerical solutions for problems in seepage flow

January 01, 2014 12:00 AM
In many problems with seepage flow, there are non-linear problems that don’t have an easy analytical solution. There is already good research on what can be done in certain situations with these problems. I will present on numerical methods that have been proven to solve certain conditions and then present other solutions for similar problems where the numerical method isn’t so readily available in past research. I will implement the algorithms and compare results.

Assessment of Environmental Awareness among Utah Valley University Students

January 01, 2014 12:00 AM
Utah County, Utah has an estimated population of 540,000 residents and is considered to be a non-attainment area for criteria pollutants such as PM-10 and CO. High levels of these contaminants may increase the risk of respiratory diseases. Additional environmental issues exist including water contamination and eutrophication of Utah Lake. These environmental issues are frequently on the news and warnings are issued by the Department of Environmental Quality notifying citizens of the potential health concerns associated with environmental pollution. With these announcements, it is expected that Utahans are acutely aware of environmental issues, particularly, in the academic settings. The purpose of this study was to investigate the status of environmental awareness among students at Utah Valley University and to correlate the results to socio-demographic categories. Utah Valley University, located in Utah County, is a public institution of higher education with approximately 30,000 registered students. Data for this study was collected through a survey using a multistage sampling technique with population stratified based on colleges and schools within the university. Sample size included approximately 1,000 students. The survey contained 12 environmental questions relating to recent local, national and international media exposure. Standards and protocol of the International Research Board were employed. We hypothesize that married, educated, religious males will positively correlate with higher levels of environmental awareness, but will be less than atheists. Additionally, those identifying with the Republican Party will have lower levels of awareness. No significant difference will be found between majors. Furthermore the young, poor and ethnic populations will be less aware than their more affluent counterparts. Results of this study will be used to inform residents of environmental issues and the associated health concerns. Additionally, this study will be used to inform legislators about the importance of environmental education in the community.

Size, Personality, and Evolution: Examining Predictions in Two Live-bearing Fishes

January 01, 2014 12:00 AM
The recent surge of interest in personality differences between individuals of a single population or members of differing populations has generated numerous new hypotheses that may aid in elucidating patterns of ecology and evolution that were previously considered improbable. Two hypotheses relevant to fish biology relate the size of an organism from a certain predation environment to the level of boldness it exhibits. The first of these (predation hypothesis) predicts small individuals living with predators should not express boldness comparable to their larger counterparts, whereas the other (metabolic hypothesis) predicts the exact opposite. Our study investigated these hypotheses using two sister-taxa fish species in Panama (Brachyrhaphis roseni and B. terrabensis) that exhibit two size classes (large and small) and live in differing predation environments. Additionally, because males are smaller than females in both species, we could look at size-boldness relations within each species. The study, as in others, defined boldness as the amount of time for an individual to emerge from a shelter and into an unfamiliar territory. When the species are analyzed collectively, our results support previous findings that fish from high-predation environments tend to be bolder than those without predators; males tend to be bolder than females; and both mass and standard length positively correlate with boldness. However, within species analyses find that mass and standard length have no significant relation to boldness, and gender was only significant in the predation-exposed B.roseni, where males were bolder. These interesting findings contrast with previous studies, and lead us to question the value of these size-related hypotheses in the process of speciation and, ultimately, evolution.

Dna Based Identification and Prevalence of Cestode Parasites in the Brine Shrimp (Artemia franciscana) from Great Salt Lake, Utah

January 01, 2014 12:00 AM
The brine shrimp, Artemia franciscana are an important source of nutrients for many of the over 15 million migratory birds that visit Great Salt Lake (GSL) in Utah each year. As well as being a source of food, the brine shrimp are an intermediate host to cestode parasites that infect many of the bird species. Although the effects of cestode infection in brine shrimp and the contribution of brine shrimp to cestode circulation in birds have been studied, little research has yet addressed the rate of cestode infection or molecular phylogeny of these cestodes. We collected brine shrimp from three sites in GSL and tested individuals for cestode infection using previously identified and newly designed cestode specific PCR primers that amplify the 18S ribosomal RNA gene. Our preliminary results showed that the Spiral Jetty site from the North arm of GSL had a 2% infection rate, the Antelope Island site from the South arm had a 45% infection rate, and the shrimp collected at the Black Rock site, also in the South arm, had a 32% infection rate using our cestode specific PCR assays. We also have preliminary DNA sequencing results that demonstrate that we are amplifying cestode DNA, which is most closely related to members of the genus Hymenolepis. Our data suggest that there may be a higher prevalence of cestode infection in the shrimp in the South arm than those from the North arm of the Great Salt Lake. Our goal is to extend our study in order to better identify the species of cestodes that infect brine shrimp using further DNA sequencing and to expand our infection rate samples to better estimate the percentage of the brine shrimp population that is infected by the cestode parasites, as well as test samples from several years.

PP2A inhibition using LB1 negates palmitate-induced reductions in nitric oxide production in endothelial cells

January 01, 2014 12:00 AM
Cardiovascular complications (e.g., arterial dysfunction) are more prevalent in patients with type 2 diabetes (T2DM). Patients with T2DM have elevated levels of circulating free fatty acids (FFAs). We have shown that when bovine aortic endothelial cells (BAECs) are treated with the physiologically relevant FFA palmitate, protein phosphatase 2A (PP2A) activity increases, phosphorylated endothelial nitric oxide (NO) synthase (eNOS) to total eNOS (p-eNOS:eNOS) decreases, and metabolites of NO production decrease. NO is an important endothelial-derived relaxing factor that is vasculoprotective. As such, FFA-induced, PP2A-mediated reductions in p-eNOS:eNOS and NO production might explain why vascular complications are more common in pathologies associated with lipotoxicity e.g., T2DM and diet-induced obesity. Recently we showed in BAECs that if PP2A is inhibited using okadaic acid (OA), palmitate-induced increases in PP2A activity, and reductions in p-eNOS:eNOS and indices of NO production are negated. We sought to translate these finding from BAECs to the intact organism. However, OA cannot be used in vivo. Lixte Biotechnology 1 (LB1) is a PP2A inhibitor that has been used in vivo in the context of cancer research. The purpose of this study was to determine the efficacy of LB1 under our experimental conditions, with the long-range goal of using LB1 in mice. Further, we used this opportunity to optimize the measurement of NO directly using electron paramagnetic resonance spectroscopy (EPR). BAECs were treated for 3 h with vehicle (V), 500 µM palmitate (P), 4 µM LB1, or P + LB1 (n=10 per treatment). P increased (p<0.05) PP2A activity (50±12%), and decreased (p<0.05) p-tyr307:PP2A (29±9%; redundant indicator of increased PP2A activity), p-eNOS:eNOS (30±3%), and NO production (27±9%). All P-induced effects were prevented by concurrent treatment with LB1. Future experiments will determine whether chronic treatment of mice with LB1 is capable of suppressing PP2A activity in intact arteries.

Edge effect on vegetation type and cover along a popular recreational trail

January 01, 2014 12:00 AM
Heavy foot traffic compacts soil, leading to decreased gas exchange, water permeability, and reduced nutrient cycling. Plant communities are defined by the availability of nutrients, water, and other resources.

Using Microsatellite Markers to Characterize Genetic Diversity of Utah Agave and its Subspecies

January 01, 2014 12:00 AM
Agave utahensis (Utah agave) plays a critical role as a keystone species in its native habitat. A rise in frequent, intense fires across the range of these habitats threatens to eliminate Utah agave populations, and consequently limit its genetic diversity. Characterizing the genetic diversity of Utah agave and its subspecies will help in restoration efforts to protect the species. We constructed primers to amplify microsatellite markers of two subspecies of Utah agave, ssp. kaibabensis and ssp. utahensis. Using these markers, we determined the level of polymorphism within four populations of each of the two subspecies.

The effects of imidacloprid on Atremia franciscana

January 01, 2014 12:00 AM
Imidacloprid is a popular systemic insecticide that has been applied to our staple crops for two decades. According to the EPA, it is persistent in the environment and at risk of effecting non-targeted organisms. Imidacloprid is an insect neurotoxin; however it is also known to be toxic to various aquatic species in concentrations as low as 37 ppb. Ingestion of imidacloprid causes paralysis in organisms through the blockage of postsynaptic nicotinic cholinergic receptors. We sought to find out how toxic imidacloprid is to brine shrimp and what kinds of physiological reactions occur upon exposure.

Development of sensitive ELISA and qPCR assays to quantitate levels of dust mite antigens in homes in Utah with and without swamp coolers

January 01, 2014 12:00 AM
Asthma is a chronic allergic disorder manifest by airway restriction due to inflammation, bronchoconstriction, and increased respiratory mucous secretion. As many as 300 million people worldwide are affected by asthma and its prevalence is increasing primarily in countries experiencing urbanization and Westernization. Asthma is currently the most common chronic illness among children in the U.S., and the third leading cause of hospitalization for children aged 0 – 15 yrs. Reservoir dust collection and area air sampling are the two primary methods of measuring allergen levels in house dust. Allergen sensitization leading to asthma is thought to occur prior to age six while the immune system is still naïve. In the case of the dust mite allergen Der p1, the exposure window may be as early as age two. However, little evidence is available to establish a dose–response relationship between inhalation exposure and early immunological sensitization to allergens. Temperature and relative humidity play a major role in dust mite survival and proliferation and indoor humidity above 50-60% in arid environments has been shown to support dust mite populations. Evaporative “swamp” coolers cool air by adding humidity to it and can create favorable environments for dust mite survival. We are working to determine how much swamp coolers contribute to dust mite levels in Utah by quantitating dust mite allergen levels in homes with and without swamp coolers. In order to do this we are developing sensitive ELISA and quantitative PCR methods to allow us to determine levels of exposure even when low levels of dust are collected.

Comparative Analysis of Small Transducers and Large Transducers using High-Frequency Ultrasound on Phantom Breast Tissue

January 01, 2014 12:00 AM
High-frequency (HF) ultrasound in the 20-80 MHz range has recently been found to be sensitive to pathology in tissue margins from breast cancer surgery. In order to improve the resolution and sensitivity of this method, however, transducers need to be employed that have piezoelectric elements that are smaller than those currently in use. The purpose of this study was to determine if small element transducers (Blatek pachyometer, 50 MHz, element diameter < 2 mm) produce similar results as those obtained from large element immersion transducers (Olympus NDT, V358-SU, 50 MHz, 6.35-mm diameter active element). Ultrasonic tests were performed on 10 phantom breast samples made of Knox gelatin base and soluble fiber (Metamucil), five of which contained chopped nylon fibers and five which contained polyethylene microspheres. Pulse-echo and through transmission measurements using a HF square-wave pulser/receiver (UTEX, UT340) and a digital storage oscilloscope (Agilent, DSOX3104A, 1 GHz, 4 analog channels) were acquired from a total of 3 sites per phantom in triplicate, first testing all specimens with the large transducers then again with the small transducers. Specimens were marked with India ink for location and accuracy of testing. The density of peaks in the ultrasonic spectra of the small transducers paralleled those of large transducers. Results from HF ultrasonic measurements of phantom breast tissue obtained from small transducers compared to the large transducers indicate that they produce statistically comparable peak densities. In breast conservations surgery it is crucial to excise all cancerous tissue to prevent recurrence. This method could provide in vivo cancer detections in margins and allow for more precise excision of tumors and cancerous tissue preventing the need for subsequent surgeries and thus, less risk, reduced pain and suffering, lower costs and better outcomes for breast cancer patients.

Macroinvertebrate Assemblage as an Indicator of Urban Stream Health

January 01, 2014 12:00 AM
Urban stream syndrome is the phenomenon of stream degradation as streams run from their sources through urban areas, which is exhibited by nutrient loading, decreased dissolved oxygen, changes in channel structure, and increased turbidity and rapid flow events. This can have a direct negative effect on our recreation, drinking water, and the ecosystems surrounding the streams. To discover if urban stream syndrome occurs in the Salt Lake Valley, we monitored pH, turbidity, dissolved oxygen, dissolved nitrates, and collected macroinvertebrates in three streams monthly. We analyzed total abundance, species diversity, and percent pollution sensitive species to assess the macroinvertebrate communities, as known indicators of water quality. Preliminary data shows a significant decrease in percent sensitive species in the urban areas as compared to the nonurban areas over 10 sampling periods. We found decreased biodiversity and fewer sensitive species in urban areas, although we found no difference in total abundance. These findings indicate that urbanization in the Salt Lake Valley leads to degradation in riparian ecosystems and suggest that further investigation is needed to identify the mechanisms leading to this degradation.

Exercise Reverses Stress-induced LTP Reduction in the Hippocampus

January 01, 2014 12:00 AM
Acute stress has been shown to decrease Long-Term Potentiation (LTP) in the CA1 region of the mouse hippocampus. Stressed animals also show signs of anxiety and suffer decreases in spatial memory tasks such as object recognition and maze navigation. Conversely, exercise has been shown to increase spatial memory task performance in mice, attenuate anxiety-like behaviors and enhance neurogenesis and LTP in the dentate-gyrus. While the effects of stress and exercise have been examined independently, there is currently a lack of experimental evidence that connects how stress and exercise, when experienced by the same animal, might modulate LTP in the CA1 region of the hippocampus. In our ongoing study, mice have been separated into a control group, a stress group (restraint and tail-shock), and an exercise with stress group where mice have voluntary access to a running wheel (for 30 days) before undergoing the stress protocol.

Pamphlet and Survey of Common Insects of Capitol Reef National Park

January 01, 2014 12:00 AM
Although the insect fauna of the Colorado Plateau region are somewhat well known, our specific understanding of the arthropod biodiversity in Capitol Reef National Park is sparse.

Differentiating Molecular Subtypes of Breast Cancer Using High-Frequency Ultrasound

January 01, 2014 12:00 AM
High-frequency (HF) ultrasound (20-80 MHz) has been previously used to detect differences in microstructures and cell materials of different breast tissues types. These differences were used to distinguish between benign and malignant pathologies in different breast tissues. This same technology is predicted to be able to improve methods of detecting changes in cellular activity before changes in pathology take place. The purpose of this study was to use HF ultrasound to detect changes in the actin cytoskeleton, extracellular matrix (ECM), and integrin signaling, therefore differentiating the molecular subtypes associated with these changes in cell biomechanical properties. It is predicted that these cellular changes will also be associated with changes in the ultrasonic properties of breast cancer cells. The ability to rapidly and inexpensively detect the genetic changes or molecular subtypes of breast cancer would greatly impact and personalize patient treatment as well as provide more precise surgical removal of malignant and premalignant tissue. In order to test this hypothesis, four different breast cancer molecular subtypes including luminal A, luminal B, Her2+, and basal (triple negative) were grown as monolayer cell cultures. These subtypes were chosen because of their range of aggressiveness (luminal A as least aggressive and basal as most). After growth at different seeding levels, cell cultures were tested with a HF ultrasound system using a 50 MHz, 6.35-mm diameter immersion transducer and pulse-echo transmission. The data was compared to simulations using multipole expansions which predicted ultrasonic scattering based on possible variations in the biomechanical properties of malignant cells. The analyzed data showed differences in the spectra of waveform signals between each tested breast cancer molecular subtype. It is anticipated that this technique would provide an efficient and cost-effective method for differentiating between different molecular subtypes of breast cancer.

Macrophage polarization by necrotic and apoptotic cancer cells

January 01, 2014 12:00 AM
Macrophages play an important role in innate and adaptive immune responses, inflammation, and tissue repair and are characterized by two distinct phenotypes: classically-activated (M1) and alternatively-activated (M2) macrophages. M1 macrophages are characterized by a pro-inflammatory phenotype and are involved in production of pro-inflammatory cytokines and aggressive engulfment, whereas M2 macrophages are characterized by an anti-inflammatory phenotype and are involved in production of anti-inflammatory cytokines (e.g. IL-10) and tissue repair. Macrophage engulfment of apoptotic cells leads to polarization toward the M2 phenotype and is thus “immunologically silent”. Additionally, there is evidence that tumor-associated macrophages (TAMs) tend toward an M2 phenotype and as a result offer protection from an immune response in the tumor microenvironment. To further investigate the role of necrotic and apoptotic cells in regulating macrophage polarization, we cultured human macrophages with necrotic, apoptotic, or standard viable Raji cells and fluorescent beads and performed an engulfment assay. In a preliminary study we found that macrophages cultured with apoptotic cells showed a decrease in engulfment levels compared to macrophages cultured with necrotic cells. Macrophages cultured with standard viable Raji cells had the lowest levels of engulfment compared to macrophages cultured with apoptotic cells or necrotic cells. Thus, in our initial experiments macrophages cultured with necrotic cells appear to have a more “M1” phenotype, whereas macrophages cultured with apoptotic cells appear to have a more “M2” phenotype. Further experiments are necessary to validate this preliminary data and further characterize the capabilities of necrotic and apoptotic cells to differentially polarize macrophages. If these observations are replicated, it has potential applications in cancer biology and therapeutics, atherosclerosis, diabetes, autoimmunity, and other diseases with an inflammatory component.

High Intake of Soy and Selenium Reduces Prostate Cancer Risk: Does Timing of Intervention Matter?

January 01, 2014 12:00 AM
Increased intake of selenium (Se) and soy have both been shown to reduce risk for prostate cancer, especially if these dietary treatments are combined. The purpose of this project is to determine how the timing of Se supplementation of either a low- or high-soy diet affects prostate cancer risk. [C57BL/6 X FVB] F1 TRAMP (TRansgenic Adenocarcinoma of Mouse Prostate) male mice were fed stock diets low or high in soy. Half of the mice received Se supplementation (4.0 mg Se/kg BW as Se-methylselenocysteine) by gavage 5 d/wk in a 2 X 2 factorial design. Se supplementation began at conception, 6 weeks, 12 weeks, or 18 weeks of age. The mice were then sacrificed at different stages of maturation (4, 12, 18, and 24 weeks). Our results showed that, at 12 weeks of age, urogenital tract weights, a measure of prostate proliferation and tumor volume, were significantly reduced by Se supplementation (p<0.001) and by soy (p=0.044), independent of time of dietary intervention. Histological scores of prostate cancer progression also showed a protective effect of Se supplementation (p=0.030). At this writing, statistical analysis of data from mice sacrificed at 18 weeks is in process. Data derived from 18-week mice, combined with our previous findings from 12-week animals, will allow us to chart the progress of prostate cancer in this model. In addition, results will show how dietary Se and soy may alter disease progression and how the timing of dietary intervention may determine its effects.