Rigorous Academics Inspire a Career in Physics


When he enrolled at Allegheny, Colby Mangini ’04 thought he’d probably major in international studies. He had studied Spanish in high school, and international business and economics sounded interesting. He wanted a college degree but wasn’t exactly passionate about academics.

“I wasn’t challenged that much in high school and could get by doing the bare minimum, so I did,” he says.

During his first semester, Mangini decided to get his science requirement out of the way and signed up for Physics 101 with Dr. James Lombardi, Sr. As it turns out, that single introductory course would change the trajectory of Mangini’s studies, and shape his future career.

Now, a little over a decade since he graduated summa cum laude with a bachelor’s degree in physics, Mangini holds a doctorate in radiation health physics and is board certified in the field, both accomplishments that have helped fast-track his career and allowed him to play a major role in the treatment of children who are battling cancer.

In his current position as radiation safety officer at St. Jude Children’s Research Hospital in Memphis, Mangini makes sure that patients and their families, along with staff, and members of the local community are safe from the potentially damaging effects of radiation used in medical and research applications within the hospital. He also ensures radiation-emitting material does not escape into the environment and that St. Jude’s programs comply with state and federal regulations.

There are a lot of uses for radioactive materials in a hospital setting. X-rays and CT scans probably come to mind but there are also radioactive materials that are injected into patients so that doctors can capture an image of say, the thyroid gland, and radioactive materials and equipment used to treat cancers. Additionally, at a research hospital, various radioactive substances are being generated and used in laboratories.

It is Mangini’s job to be certain X-ray machines are properly shielded by lead walls. He makes sure patients with a radioactive substance in their bodies do not contaminate other patients or their family members, and that the rooms where they stayed are properly decontaminated. He must see that nothing escapes the lab setting in which it is meant to be contained.

Most hospitals have radiation safety officers, but Mangini’s role at St. Jude presents a unique challenge. St. Jude houses a revolutionary new device, the 230 MeV proton synchrotron, that uses a thin beam of protons to treat tumors. It is one of a few of its kind in the world, and the only unit dedicated solely to pediatric care.

“St. Jude’s proton accelerator uses pencil-beam technology,” explains Mangini. “If you could see the proton beam it would look like a laser pointer.” The device allows doctors to direct a stream of radiation at a tumor with great accuracy, meaning less damage to neighboring tissue and skin. It means tumors near sensitive areas of the body, such as the brainstem can be safely treated with radiation. Less damage to healthy tissues means less recovery time for patients. It also improves outcomes down the road, with fewer patients experiencing recurring or secondary cancers related to radiation treatment.

“When protons hit the patient, it creates a secondary radiation field comprised of neutrons and gamma rays,” Mangini says. “The protons stop at the patient—they destroy the cancer—but the other particles don’t.”

That is where Mangini and his team come in. They make sure the rooms housing the proton beam technology have the proper amount of shielding in the walls and that the secondary radiation is not escaping into the hallway or waiting area where a patient’s family is sitting. They make sure the people working on the floor above the Proton Therapy Center aren’t exposed, and that appropriate staff wear personal dosimeters, which monitor their exposure to radiation.

Mangini also helps to educate St. Jude employees whose work takes them into the proton facility. “People fear radiation,” he says, “because they don’t know a lot about it. I spend a lot of my time communicating to staff members about what is happening inside the proton facility, what they could be exposed to, and what we have in place—the shielding, and safety systems.”

It is a big job with an endless list of responsibilities, which, for Mangini, is both the challenge and the reward. “What they are doing here at St. Jude is cutting edge. If something I do falls by the wayside or I don’t do something correctly or something happens to the safety systems or there’s a regulatory issue, all that work could come to a stop. It increases the importance of everything we do.”

A Student Motivated by Challenges

In order to jump from Physics 101, a course intended for non-majors, into the curriculum for physics majors, Mangini had to get a waiver. He first sought the advice of physics professor Doros Petasis. Mangini left that conversation feeling that the transition into the major would be doable but difficult. “I saw this as a challenge and always remembered that feeling,” says Mangini, who received the waiver. “I was determined to be the top student in every physics class thereafter.”

“Allegheny was a huge step up from high school,” Mangini says. “When it started to become clear—what I could achieve in college, I had more motivation. I was challenged and applied myself a lot more.”

Mangini says he discovered, while in college, that he is motivated by setting personal goals for himself, which meant, at Allegheny, GPA goals. After college, his goal was to become an officer in the Navy. Mangini realized that this pursuit could also fulfill another of his goals: to explore the love of teaching he developed while he was a physics tutor at Allegheny. Eventually, he became a senior instructor and lieutenant in the Navy.

Teaching in the Navy had its own set of motivating challenges. At first, Mangini wasn’t teaching physics, but nuclear and mechanical engineering, which meant, he had to teach himself the material before he could teach it to his classes. “I had to learn everything involved with how a reactor core takes nuclear fuel and causes a propeller to rotate at the back of a boat,” he says. Mangini again rose to the challenge and excelled. He was awarded “Master Training Specialist” designation by the Navy.

After completing his four-year term in the Navy, while simultaneously earning a master’s degree in health physics from Oregon State University via distance education (he was stationed in South Carolina), Mangini decided to take Petasis’ advice. He and his wife, Kyla Vandree ’04 Mangini moved to Corvallis, Oregon, and he enrolled in Oregon State’s doctorate program.

While there, Colby reworked the code for VARSKIN, a computer program that helps to estimate the amount of biological damage received by skin when it comes into contact with radioactive material. VARSKIN’s ability to produce an accurate estimation was poor under certain conditions. Mangini spent many nights awake in bed thinking over the problem. He had to figure out where the weakness was in the code, then how to write a better code.

“I developed a new physics model that could be used to more accurately estimate the biological damage from high energy electrons,” he says. “I incorporated that model into the computer code itself, so the latest version of that code uses my model. I still consult and trouble-shoot that code.”

Throughout Mangini’s academic career, Professor Petasis has continued to inspire him to excel. The professor’s initial hesitation about Mangini’s promise as a physics student quickly changed to enthusiasm. He “took me under his wing,” says Mangini. Petasis encouraged him to do undergraduate research and to pursue an academic career in physics. “Him having that belief in me, that I was capable of a Ph.D., was always in the back of my mind as my career progressed.”

Rachel Mangini wrote this story. She is a freelance writer in Warren, Pa.

Photo courtesy of Colby Mangini

Source: Academics, Publications & Research