THE CORNELL DAILY SUN | Wednesday, October 10, 2012 9
SCIENCE
Wijaya ’15, Chua ’14 and Lin ’15 Win International Mathematical Contest With Leaf Predicting Program By Jessica Harvey Sun Staff Writer
It was the story of David and Goliath as a Cornell team of engineers beat over 3,600 mathematics majors from around the world to become national champions in the International Mathematical Contest in Modeling (IMCM) 2012 this past spring. Alvin Wijaya ’15, electrical and computing engineering; Dennis Chua ’14, chemical engineering; and Jessie Lin ’15, electrical and computing engineering, used their programming skills to win the Mathematical Association of America
COURTESY OF PROF. JULIUS LUCKS
Plant predictions | Dennis Chua ’14 explains his teams probability program for predicting the amount of leaves on a tree.
(MAA) Award with their software program that simulates the growth of tree leaves based on sunlight patterns and calculates their masses. Using MATLAB, a mathematical programming software, Wijaya, Chua and Lin designed a program that would have real life application to scientists around the world. According to the team, their software will help researchers approximate two things: the most-likely leaf shape for a given tree in a given region, and the total mass of all the leaves in that tree. By using the team’s software, researchers no longer have to physically go to a tree to categorize and count each of its leaves. Instead they can simply use the modeling system to approximate the information needed. According to Lin, the process of creating, designing and implementing a modeling software program was difficult, but rewarding. “We racked our brains to come up with an implementable model that was reliable and flexible at the same time,” Lin said. “We began with a basic model that was built mainly on probability and then expanded it to take into account the geometry of the tree, the region of growth,and the season.” The predicted leaf shape and mass numbers that come from their software are precise, according to Wijaya. He said that the team crosschecked their results with real data and found it to be accurate and applicable for scientists. The team said they were thrilled with not only the accuracy and real life application of their program, but also with their success at the IMCM. Their competition — mostly junior and seniors mathematics majors — was intimidating, according to Wijaya, so winning was a pleasant surprise for them. Historically, he said, the winning projects had primary foundation in mathematics, but their model mostly relied on programming skills and a simulation idea,
COURTESY OF PROF. JULIUS LUCKS
Mathletes | Alvin Wijaya ’15 and Dennis Chua ’14 recieved the Mathematical Association of America Award in Spring of 2012 and the pair represented Cornell at MathFest 2012.
rather than pure math knowledge. “Going into the competition, we thought our design was pretty simple, but it turns out that we did it quite well. We went there without any hope of winning, but then we won it. It was mind-blowing,” said Wijaya. “My favorite part was writing the program for our rigorous models.” Chua said. “I ended up writing over 4000 lines of code over four practically sleepless nights. It was all worth it when we ran both models at the end and they produced highly corroborative results.” According to Chua, the team had only four days to perform everything, including the design of the software program and the paper writing portion. The team said working together as a unit was crucial. “Dennis was our main software programmer and came up with the idea of
using a fractal-based model,” Wijaya said. “I was the online researcher and the mathematical analyst and came up with the idea of a 3-D fractal-based model, and Jessie was the mathematics formulator and came up with the idea of time-based simulation model.” The team said that they hope to extend their software beyond tree leaves and into various other types of plants across the world in various regions and climates. Wijaya said he was proud of his team’s accomplishment. “If you’re a freshman, don’t be afraid to try projects like this. You can do it,” he said. Wijaya and Chua also presented their award-winnin software at MathFest 2012, the largest annual mathematics conference, in August in Madison, Wisconsin. Jessica Harvey can be reached at jharvey@cornell.edu.
Just Say ‘Know!’ Prof. Harris-Warrick Discusses The Effects of Drugs on the Brain By LISA GIBSON
The first frenzy of papers and prelims hit campus these past few weeks, and perhaps you were one of the many students downing coffee or caffeinated energy drinks to help stay awake at 3 a.m. in the library. But amidst the cramming of Punnett squares, Newman projections, and Schrödinger solutions, there was a fury of other biological activities taking place in your brain caused by the caffeine in your drinks. Professor Ron HarrisWarrick, neurobiology and behavior, spoke about the effects that drugs and stimulants like caffeine have on the brain at an event held in Willard Straight, hosted by Cornell Minds Matter, an organization that supports mental health education. Harris-Warrick teaches BioNB 3920: Drugs on the Brain. While most people don’t think of caffeine as a drug in the sense that they might think of cocaine, caffeine’s addictive properties are similar from a biological perspective. Dopamine, a neurotransmitter, is released in your brain as
a number of different drugs in his presentation. Alcohol is a legal drug, and most adults have tried it at least once in “Knowledge is strength. Intelligient their lives. In decisions are made based on knowing moderation, alcohol usuconsequences of behavior” ally does not cause probProf. Harris-Warrick lems, and may actually The dopamine signal is a learn- have some health benefits. Some ing signal: it detects rewards and individuals become addicted, attaches value to objects and but most do not. The difference behaviors by activating the is due to genetics. Some people reward system. are predisposed to being addictHarris-Warrick also spoke of ed to alcohol, so in understandthe importance of knowing ing the drug’s affect on a person, what happens in the brain when it is important to know that perdrugs are involved. Cocaine is son’s family history. the best understood model, he Other drugs, like nicotine, said. It hijacks the dopamine are more addictive, he said. reward system by directly acti- About one third of all smokers vating it, and bypassing normal become addicted to nicotine. perceptual senses like taste buds Another example he spoke or sugar sensors. By bypassing about was ecstasy. Ecstasy is the senses, cocaine enhances the sometimes called the love drug release of dopamine so that tak- or hug drug because it often ing the drug is perceived as enhances empathy in the user. highly rewarding. The reward is It has more psychological associated with cues, behaviors effects that most other drugs or surroundings associated with and produces a long-lasting loss taking the drug. Cues are often of function in the mood regulatthe first step of many that leads ing neurotransmitter serotonin to addiction. function. The brain may never Harris-Warrick spoke about fully recover from the loss. to expectations. If the stimulus is better than expected, signals to release dopamine are sent.
Sun Staff Writer
COURTESY OF DEPT. OF NEUROBIOLOGY
Neuro notes | Prof. HarrisWarrick teaches about how drugs interact with the brain.
part of the reward pathway. The neurotransmitter is a chemical signal that is passed from neuron to neuron across a synapse, the point of communication between two neurons. All drugs that produce mood and perception changes affect the brain’s dopamine reward system by affecting the chemical conversation between nerve cells at synapses. This holds true for drinking coffee inside the library or smoking cigarettes outside the pub. The reward pathway registers values of rewards compared
Abusing ecstasy may cause depression and decreased cognitive ability. Even though addiction occurs in the same way for all psychoactive drugs, it is important not to group all drugs as the same because the consequences and effects on life are different, said Harris-Warrick. “Knowledge is strength,” he said. “It helps you make intelligent decisions. Intelligent decisions are made based on knowing consequences of behavior.” Drugs have a powerful effect on the brain because it changes the brain’s biochemistry, and treatment for drug addiction is not merely stopping the act of using the drug. There is no single method of treatment; a battery of treatments like medical treatment, psychiatric therapy and social therapy may be necessary to help. Harris-Warrick said however, that the most important aid in overcoming drug abuse is a supportive environment. It is also important to recognize the role of friends in identifying when someone needs help and in supporting someone. Lisa Gibson can be reached at egibson@cornellsun.com.