Investigating RNAi in Manduca sexta using BAPCs

The goal of this research is to find an improved method for interfering with gene expression in insects, which can be important agricultural pests. Genes contain the information that tell cells/organisms how to function. When a gene is expressed, a copy of the gene is made of RNA; this copy is known as messenger RNA (mRNA). One method to study a gene’s importance would be to interfere with its expression and observe the effect it has on the organism. This can be accomplished by a technique called RNA interference (RNAi). When double stranded RNA (dsRNA) is introduced into a cell, it is recognized as being non-natural to the cell and a possible indication of viral infection. If the cell finds an mRNA that is a match to the dsRNA, it is targeted for degradation. In RNAi, if we introduce dsRNA that matches a gene we are interested in, the corresponding mRNA will be degraded. This method has proven to be very useful for studying gene function. However, this technique has not been very successful in butterflies and moths, possibly because of enzymes that break down the dsRNA before it can get into cells. A method to protect the dsRNA could make this method more effective. Branched Amphiphilic Peptide Capsules (BAPCs) are small protein nanocapsules that have been used successfully to deliver dsRNA in insects. We want to test if BAPCs will be helpful to deliver dsRNA in the caterpillar of the moth Manduca sexta. To test this technique, we targeted the two genes that encode for insecticyanin, a protein that is responsible for the green color of the caterpillars. If successful, the color of the caterpillars should be lighter green or white. Caterpillars were fed a solution that contained dsRNA for insecticyanin complexed with BAPCs. The caterpillars were monitored for a week to observe their color pattern. We also monitored the color of their hemolymph (blood) which is also green because of the presence of insecticyanin. In preliminary experiments, caterpillars fed the dsRNA/BAPC complexes looked similar to caterpillars fed a sugar solution. This suggests that either RNAi didn’t work or was too minimal to affect insecticyanin protein levels

Through the Storm, Through the Rain: The Realities of Climate Change and the Need for New Engagement in Hampton Roads, VA

Social Vulnerability Panelists, moderated by Lynda Butler, will share their perspectives and analyses on the intersections among race, law, science and environmental justice in community vulnerability assessments

Adventures in Flute Playing: A Literature Survey and Anticipated Beginning Flute Method

This Literature Survey will investigate 10 method books used by beginning flute students, aged 6-13, in the United States. In this survey, books will be analyzed to identify which musical concepts are covered and their overall methodical approach. Comprehensive graphs are offered in the Appendix to provide readers brief contextual information on the books analyzed. The results from this survey have influenced the creation of my beginning flute method, Adventures in Flute Playing, which incorporates exercises that are less commonly found in the method books being used today. Adventures in Flute Playing will consist of a series of online videos with a guidebook of supplemental exercises available for purchase via hard copy or PDF digital download. The Adventures in Flute Playing guidebook will be available for purchase for flute teachers, parents, and music vendors. QR Codes are placed throughout the guidebook to provide users easy access to video demonstrations and practice videos. The intended audience for Adventures in Flute Playing is beginning grade school and middle school students; however, beginners of all levels could find this method helpful

Testing and Analysis of a Post-Tensioned Coupled Wall System monitored with Multiple Digital Image Correlation Systems

This thesis discusses the design and experimental evaluation of a novel seismic resistant reinforced concrete (RC) coupled shear wall system. In this system, the widely-used unbonded post-tensioned floor slab construction method is adapted to couple (i.e., link) two RC wall piers, providing significant performance and construction benefits over conventional RC coupling beams in high seismic regions. Previous experiments of post-tensioned coupled wall structures are limited to floor-level coupling beam subassemblies. The current study extends the available research to multi-story structures by construction and testing of a 15% scale eight story prototype specimen. This test is monitored by four digital image correlation systems simultaneously in order to gather data from all necessary areas of the specimen. The experimental specimen includes the foundation, the first three floors of the shear walls, and the associated coupling beams. The upper stories of the building are simulated with hydraulic jacks that supply the appropriate bending moment, shear, and axial forces at the top of the laboratory structure. This thesis compares the measured displacements and derived parameters of the laboratory structure measured by the digital image correlation systems with predictions from design models. Experimental and design predictions of several key behavior parameters are shown to match well. Several design parameters that are unable to be measured from the specimen are able to be predicted using the validated models. Coordination of the four simultaneous digital image correlation systems presented some challenges -- recommendations for future deployment are discussed. Future work involves the construction and testing of large scale (40%) specimens to validate the approach

Exploring the Potential of Sucralose as a Cryopreservative for Red Blood Cells

Cryopreservation is a technique that involves freezing living cells to preserve them in long-term storage. Freezing and preserving living cells would not be possible without the assistance of cryopreservatives. Many cryopreservatives like DMSO and glycerol are currently used to protect living cells as they freeze. However, because of potential toxicity and the need for washing steps in blood transfusion medicine, there is need for alternative cryopreservatives that are both effective and safe for living cells. In this paper, sucralose, an artificial sweetener, is tested as a cryopreservative at varying concentrations. In addition, sucralose was paired with a traditional cryopreservative, DMSO, to observe if its efficacy was altered. The study showed that sucralose does offer cryoprotective ability, and its protection increases as the concentration increases. Pairing cryopreservatives was shown to be less effective. Presented data could be useful in further study of cryopreservation and transfusion medicine

A Community-Based Participatory Assessment of Fish Consumption and Dietary Mercury Exposure along the Lower James River, Virginia USA

The use of community-based participatory research (CBPR) methods to conduct environmental exposure assessments provides valuable insight about disparities in fish consumption and contaminant exposure. Ninety-five community-specific fish consumption surveys were administered to low-income African American women (ages 16--49) residing in the Southeast community of Newport News, Virginia, USA, in 2008. The mean fish consumption rate for the women surveyed was 147.8 g/day (95% CI: 117.6-185.8), a rate substantially higher than the mean fish consumption rate reported for U.S. women (1.8 g/day 95% CI: 1.51-2.04). Through collaborative partnerships established between current researchers and The Moton Community House (a local community center), African American women (ages 16--49 yrs) from the same community were surveyed in 2010 to assess the reproducibility and consistency of fish consumption patterns (ingestion rates, exposure frequencies, weight, and fish consumption rates), and the reliability of the survey responses. Fish consumption patterns were reproducible and the survey responses were reliable. Comparison between years revealed that fish consumption patterns remained consistent over time. In addition, the high fish consumption rate estimated in 2008 was reaffirmed in 2010 with a rate (134.9 g/day; 95% CI: 88--207 g/day) not materially different and still considerably higher than mean fish consumption rates reported for U.S. women. Daily mercury intake rates were estimated using consumption data from 2008 and three consumption scenarios (canned white, canned light, and no tuna) due to confirmed differences in mercury concentration between canned white and light tuna. Arithmetic mean daily mercury intake rates were 0.284 ug/kg-bw/day (95% CI: 0.229 - 0.340 ug/kg-bw/day) using canned white tuna, 0.212 ug/kg-bw/day (95% CI: 0.165 - 0.259 ug/kg-bw/day) using light tuna, and 0.197 ug/kg-bw/day (95% CI: 0.151 - 0.243 ug/kg-bw/day) using no tuna. Probabilistic estimations of dietary mercury exposure for African American women (ages 16--49) from the Southeast Community were generated and compared to point estimates. Four different consumption scenarios were assumed, representing 1) no, 2) light, 3) both light and white, and 4) white tuna consumption. The probabilistic models generated lower dietary mercury intake rates than the point estimations, under these consumption scenarios. Arithmetic mean daily mercury intake rates (95% Cl) for the probabilistic models were 0.149 (+/-0.003), 0.148 (+/-0.003), 0.172 (+/-0.004), and 0.202 (+/-0.004) ug/kg-bw/day, respectively for no, light, both, and white tuna consumption. Reducing the amount of fish consumed in probabilistic models resulted in lower dietary mercury exposures for each consumption scenario. at a rate that was a quarter of what was normally consumed, the percentages of exposures that exceeded the US EPA\u27s oral RfD for mercury were 14%, 13%, 18%, and 25% respectively for no, light, both, and white tuna consumption. In this community we learned that even though African American women in Southeast Newport News, Virginia are not subsistence fishers, they consume seafood at a subsistence fisher rate. In addition, estimates of dietary mercury exposure were high enough to warrant concern

A Stark-Effect Modulator for CO\u3csub\u3e2\u3c/sub\u3e Laser Free-Space Communications

A Stark-effect modulator prototype has been designed and constructed to transmit an RF signal upon an infrared carrier wave produced by a CO2 laser. The anticipated future use of this prototype will be to integrate it into an all-weather long-wavelength infrared (LWIR) free-space communication link. This communication system is expected to be capable of operation at 2.5 Gbits/sec over a range of \u3e6 kilometers. The Stark-effect modulator prototype is ideal to replace existing microwave and radio communication links used currently. Also, the Stark-effect modulator is a better choice than electro-optic crystal modulators and acousto-optic Bragg cell modulators because it operates at higher frequencies and is less costly. The Stark-effect occurs when an electric field is applied to a gas molecule that has a substantial polarizability. The electric field changes the spacing of the gas molecule energy levels. The gas molecule used is deuterated ammonia (NH2D) because it has a molecular absorption resonance near the 10.59 micron wavelength line of the CO2 laser emission. The modulator is a dielectric waveguide that is constructed of borosilicate glass, measuring 36-cm in length and having an inner diameter of 1.8-mm and an outer diameter of 3-mm. The modulator has been characterized successfully, with an experimental result agreeing with a predicted model. For the first time, an RF signal has been successfully applied to the Stark-effect modulator and successfully transmitted and detected by a nearby receiver