Friday, 22 February 2013 00:00
Five students from North and South High Schools were named semifinalists in the 2013 Intel Science Talent Search, a program of Society for Science & the Public. Intel is the country’s oldest pre-college science competition and is considered by many to be the most prestigious.
North High School’s semifinalists are: Deriam Chirinos, Meng Lu (Matilda) Dong, and Julia Zhuang. Deriam and Matilda’s faculty sponsor was Dr. Marie van Nieuwenhuizen, science research teacher. Julia’s faculty sponsor was Alan Schorn, science research teacher.
South High’s semifinalists are: David Kim and Cyrus Zhou. David’s research project was done independently under the guidance of a professor at Hofstra University. Cyrus worked under the guidance of a researcher at NYU, as well as with science research teachers Drs. Carol Hersh and James Truglio.
“Throwing Dice in QCD (quantum chromodynamics): Using Random Matrices to Study the QCD Hadron Spectrum” was Deriam Chirinos’ project. He explained it as follows: “Current research shows that quarks, which make up protons and neutrons, are held together by a force called the strong force that, if fully understood, could bring us closer to a universal theory of both the cosmos and the quantum world. The strong force, however, does not yield itself to successive approximations, and current research centers on non-perturbative methods. A lattice approach has shown promise but requires intensive use of supercomputers. Random Matrix Theory, however, allows one to recover the essential qualitative features in a much more effective way. I used MATLAB to simulate the quark interaction on a lattice and found that my result was consistent with results obtained from inefficient methods.” (MATLAB is a high-level technical computing language and interactive environment for numerical computation, visualization, and programming.)
Meng Lu (Matilda) Dong’s project was: “Searching for Deviations from the Cosmological Constant Concordance.” In her summary, she wrote: “The recent discovery of the accelerating expansion of the universe has raised new questions about Einstein’s cosmological constant, which is really the energy density of empty space. In particular, is the reason for this acceleration a constant energy density, or does it change in time? Complementary cosmological data sets such as the cosmic microwave background, baryon acoustic oscillations, as well as data available from Type Ia supernovae, have so far been seen to be consistent with the standard cosmic concordance model, which assumes a constant energy density. Equivalently, the jerk parameter—which is related to the change in the acceleration rate—has to be equal to one when the acceleration is caused by the cosmological constant. In recent years, the database of supernovae has grown considerably. In this project, the new data are used to further constrain the possible value of the jerk parameter, without making any assumption about the dark energy equation of state.” Fitting the supernovae luminosity to five distance functions yields a range for the jerk parameter that does not quite confirm yet that the cosmological constant is constant, but with more data to come, this approach promises to lift the uncertainty.
In his project, “Packing versus Covering in the Euclidean Plane,” David Kim studied arrangements of convex disks in the plane. “This can be envisioned,” he wrote, “by thinking of the familiar honeycomb arrangement in which hexagons completely fill a plane. Tiling a plane with regular hexagons is optimal in the sense that there is no ‘waste,’ that is, no two hexagons overlap and no point is left uncovered. If instead of hexagons, copies of a unit circle were ‘packed’ as densely as possible, a circle could be placed inside each of the hexagons of the honeycomb arrangement. The resulting circles would no longer cover the entire plane (only covering about 90.7 percent). ‘Covering’ is nearly the same as ‘packing,’ except that it looks to find the arrangement that minimizes the number of objects needed to completely cover the plane when allowing overlapping. Because ‘covering’ and ‘packing’ are complementary to each other, the project looked to find the relationship between the two, using copies of an ‘egg-shaped’ disk.” David explained further that while his project started as a “theoretical interest, just out of curiosity, because there seemed to be a unique relationship between packing and covering, there are also practical applications in the commercial world that further encouraged me to continue my project because it made the project seem to have a greater significance. For example, ‘covering’ can be used to find out the arrangement of 5 gas stations in a certain region to minimize the average distance from a house to the nearest station. (Each station can be represented as a circular region and use the circles to optimally ‘cover’ the region.) This arrangement would benefit both the customer and seller by making it easier overall for the consumers to get to the gas station.”
One of many changes that occur during aging is that the brain atrophies (shrinks). A question of current interest is whether or not the rate of shrinking is uniform over time. In his study, “Accelerated Lateral Ventricle Growth in Normal Individuals as Well as Cognitive Decliners,” Cyrus Zhou analyzed Multiple Magnetic Resonance Images (MRIs) taken over a five-year period of 101 individuals (ages varying from early fifties to late eighties) using computer techniques known as SPM8 (Statistical Parametric Mapping 8) and ALVIN (Automatic Lateral Ventricle delIneatioN). As Cyrus explained, “The size of the lateral ventricle (a fluid-filled center found within the brain) was measured and used as an indicator of total brain atrophy. The data was analyzed using a statistical model known as Random Coefficient Regression, and suggests that global brain atrophy was not uniform across all ages, but accelerated as one got older. MRI scans from 213 individuals who were declining towards Alzheimer’s were also analyzed and found to have accelerating results although with a greater rate of atrophy. It was previously believed that normal aging atrophy occurred at a linear rate, while Alzheimer’s related atrophy occurs at an accelerated rate. This study found that both normal aging atrophy and Alzheimer’s atrophy occur at an accelerated rate. This highlights the similarities between Alzheimer’s and normal aging.”
Julia Zhuang’s research project was “Analysis of Cascadia Episodic Tremor and Slip Events using Time-Dependent Displacement and Strain Fields Derived from GPS Data.” In her research, Julia analyzed strain maps of the Cascadia subduction zone (also known as the Cascadia fault, stretching from northern Vancouver Island to northern California) “in order to better understand the characteristics of strain before, during, and after episodic tremor and slip (ETS). ETS in this region refers to periodic slow-slip events usually lasting 3-4 weeks where the tectonic plates move westward instead of eastward. Previous studies examined the location and timing of the reversed slow slip motion, often in comparison to that of the associated tremor epicenters. The causes and effects of ETS have also been linked to stress distribution along the subduction plate interface. A modified version of my mentor’s strain program created displacement and strain maps derived from GPS data. ETS events were then identified in the displacement maps and compared to the corresponding strain fields. ETS events in different Cascadia subdivisions were found to have variations of the same strain characteristics, namely pure latitudinal compression in the western portion and pure extension in the eastern portion. The boundary line dividing areas of compression and areas of extension is generally consistent and matches the tremor locations and migration on the Olympic Peninsula” (the large arm of land in Washington state that lies across Puget Sound from Seattle). Julia’s research showed that “perhaps the strain maps can pinpoint the specific region on the plate interface where slow slip originates.”