Electroluminescent (EL) displays exist in a number of forms, the most prevalent being EL wire and EL panels. In either form, the mechanism of operation and functionality is essentially the same: high voltage AC current is passed through opposing conductors on either side of a phosphor substrate, inducing electrophosphorescence and illuminating the device. EL technology is not new, in fact EL panels have been used for years as backlighting elements for LCD displays (seen commonly in older radio sets and cell phones). More recently, the quality of EL products has increased drastically, especially with respect to the brightness and longevity of the devices. In addition to this, the cost of the technology is relatively low, for example: each of the panels in this project cost less than $5.

EL panels and wire are bright, colorful, and completely flexible; this has made them popular in the fields of fine and performance arts. Even though they require a high voltage, and relatively high frequency AC source, their power consumption is surprisingly low. Due in large part to the complex driving circuitry required to power the electroluminescent elements, it is still uncommon to see the technology used in low cost, portable applications; where perhaps it is the most stunning.

It is the goal of my project to build several, standalone EL panel displays that would respond to a single transmitted signal. Each standalone display will be battery powered and completely portable. The transmitted signal will deliver a response (and ultimately cause the displays to respond) to an audio signal, either voice or music. Another approach is to design each panel to respond to the ambient sound in its immediate vicinity. Both methods will be explored in this project.

During brief all-out muscular activity eliciting failure between 3 and 300 s, the level of performance available from muscle decreases exponentially between the musculoskeletal maximum and the performance supported by the body’s aerobic power(i.e.VO₂ peak). Here, the muscle duty cycle, the ratio of the durations of muscle activity to the entire movement cycle, was experimentally manipulated to alter the level of sustainable force at the condition-specific aerobic limit. We hypothesized that the expected greater levels of sustainable force output achieved in the mode with longer rest periods between contractions, were due to the greater opportunity for vascular perfusion or muscle clearance during the longer inactive periods. Therefore, we continuously measured femoral artery blood velocity via pulsed Doppler ultrasound and artery diameter by sonogram, to calculate blood flow throughout each of the 10 exhaustive bouts of knee extension exercise administered in each experimental by every subject(n = 8). This novel data acquisition technique allowed us to obtain what we believe to be the first-ever continuous measurements of blood flow by quantifying the femoral artery diameter and blood velocity during exhaustive trials. Applied muscle forces and powers were measured continuously from a custom knee-extension ergometer with strain gauges and an incremental encoder. We measured non-steady rates of oxygen uptake in Douglas bags evaluating whether the hypothesized unequal blood volumes conferred greater rates of aerobic metabolism or greater rates of muscle clearance. Our results showed the forces eliciting this common exercise intensity differed nearly 2-fold(60% duty cycle 95 ± 46N vs 30% duty cycle 184 ± 46N). Rates of oxygen uptake by muscle were similar between conditions but measured blood velocities were greater in the 30% duty cycle condition, suggesting that during high intensity exercise sustainable levels of performance are achieved through removal of accumulated metabolites rather than increased aerobic respiration.

This project highlights the connections between elastic spaces, known as topological spaces, and spaces with rigid geometric structure. It is an investigation of an infinite subset of topological spaces not yet studied which are known as corkscrew tangles. These are formed by “drilling” (conceptually) two tunnels out of a solid ball, from which the geometric structure of the tangles may be deduced.

Preliminary efforts have led to a description of the geometry of the simplest tangles in the family. Furthermore, a consistent method has been found to triangulate arbitrary tangles and this seems to be the key to finding geometric structures for the remaining tangles.

Three computer programs assist with computation necessary for the project: SnapPy, Regina, and Sage. Snappy provides information such as the volume of the tangles. Regina gives detailed descriptions about the “triangulation” of the space. Sage, a computer algebra system, is used to solve large systems of equations.

This project integrates computer skills, mathematical intuition and critical thinking skills and applies them to a contemporary issue in topology. The primary objective of the project is to develop a generalization of the geometry of these corkscrew tangles, which may be achieved by the time of the UMCUR conference.

Through its nearly 4 billion year history, life has undergone a number of major evolutionary transitions. One involved the acquisition of mitochondria by the ancestor of nucleated cells. The acquisition of mitochondria enabled these cells to respire oxygen, greatly increasing the energy they could obtain from resources like simple sugars and amino acids. Though it is widely accepted that mitochondria originated as free-living bacteria, little is known about how they came to be symbionts of their hosts. The aim of my research is to develop a model using extant microbial species that recapitulates the initial stages of this major evolutionary transition. To that end I will apply selection on the parasitic bacterium Bdellevibrio bacteriovorus and its host/prey Escherichia coli that encourages the former to reside in the latter for progressively longer periods of time without killing it. My ultimate goal is to evolve a Bdellevibrio bacterium that can reside indefinitely inside its host, which would serve as a model for the origin of another endosymbiont, the mitochondrion. No experimental model currently exists for the origin of mitochondria. By investigating the genetic basis of the transition from a parasitic to a commensal relationship between these bacteria I hope to gain insight into one of the key innovations that led to emergence of complex life that includes fungi, plants and animals, including humans.

In the search for Earth analogues, astronomers are using technology designed to detect small rocky planets in the habitable zone, the annulus around a star in which temperatures could support liquid water. Small rocky planets induce RV signals easily missed in the presence of stellar noise sources of comparable or larger amplitudes. Over the next decade, the introduction of new technology such as the James Webb Space Telescope (JWST) and the Thirty Meter Telescope (TMT) will allow astronomers to search small rocky planets’ atmospheres for biomarkers indicating the existence of past or present life. Before these telescopes take to the sky, however, it is essential that their operators know the most promising locations to investigate. MINERVA (MINiature Exoplanet Radial Velocity Array) is a dedicated exoplanet observatory with 1 meter per second precision to detect these low-mass Earth-like planets orbiting in the habitable zone of bright, nearby stars. We can determine how many planets we can expect to detect around these targets and optimize our observing strategy through the use of statistics from the NASA Kepler mission. I have produced computer-simulated MINERVA observations to quantify the observatory’s expected exoplanet yield and develop an observing strategy that will maximize the number of detections. In preliminary results, MINERVA’s expected yield is 15±4 new exoplanets with 2.2±1.5 in the habitable zone based on an average over 1000 simulations.

Halogen-bonding Catalysis

By George Neuhaus

Abstract

Catalysis plays an important role in all fields of chemistry. Many catalysts used today are heavy metals, which are avoided in pharmaceutical production due to their toxicity. This limits the variety of drugs produced because some reactions are successful only in the presence of these metals. The purpose of this research is to synthesize and test novel halogen-bonding organocatalysts that will improve pharmaceutical synthesis by opening reaction pathways that are currently only available with heavy metals. The catalysts developed will improve catalysis of Michael-type additions by which Paroxetine, an anti depressant, ZemplerⓇ, which prevents kidney disease, and (+)-tanikolide, a potential anticancer drug, are all synthesized.[1] By forming non-covalent halogen-bonds with Lewis basic species, these catalysts will lower transition state energies, which will accelerate the chemical reactions. This project develops two-halogenated imidazolium groups as halogen-bond donors placed on a terphenyl scaffold that allows the correct geometry to bind with carbonyl functionality. The binding strengths of the scaffolds were obtained by NMR titrations. Future studies will include screening Michael-type addition reactions with and without the catalysts to compare the rate of reaction. As a control, a hydrogen-bonding thiourea compound, which has proven to catalyze these types of reactions, will also be screened. This project develops a new genre of organocatalyst and promises to improve pharmaceutical production by optimizing yields, minimizing waste, and opening new pathways to a greater diversity of drugs.

[1] Maltsev, O. V., Beletskaya, I. P., Zlotin, S. G., 2011. Organocatalytic Michael and Friedel-Crafts reactions in enantioselective synthesis of biologically active compunds. Rus. Chem. Rev. 80, 1067-1113.