Basic science concepts that ultimately drive medical advances also have ties to holiday trends. The following tips offer ideas for science-themed holiday stories and the basic science experts who can offer insights.

Members of the media who would like to hear more from these scientists should contact Alexandria Carolan ([email protected]) or Vanessa Wasta ([email protected]).

A Scientist’s Perspective on When It’s Time to Toss Holiday Leftovers

Jonathan Lynch, Ph.D., assistant professor of biological chemistry, Johns Hopkins University School of Medicine

Bacteria biochemist Jonathan Lynch, Ph.D., an expert on how humans coexist with microbes, says the two-hour rule for getting rid of room-temperature holiday leftovers is based on bacteria biology. To avoid foodborne illness, Lynch says it’s important that the holiday roast cooks to the right temperature. In addition, not all bacteria are bad — Lynch says helpful microbes in the gut are responsible for breaking down holiday meals.

“Bacteria in your intestines can digest a lot of the same foods we can, like the sugar in candy canes and the infamous tryptophan in turkey, but they can also break down things in our diet that we can’t, like complex fibers from plants,” he says. “That means a big serving of green bean casserole or pumpkin pie doesn’t just feed you and your family, but also trillions of microbes living inside you.”

The “Holliday” in Our DNA

Cynthia Wolberger, Ph.D., professor and director of the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine

Over the next few months, festive themes abound in stores, social media, television and elsewhere, but one kind of holiday is always present in DNA.

The “Holliday” junction, named for scientist Robin Holliday, who introduced the concept in 1964, is a kind of crossroads of genetic material. The structure forms during the blending of genetic material, for example when sex cells combine to form a new organism, or when cells repair their DNA. Two pieces of double-stranded DNA unravel to form a junction, much like a four-way stop. Then, the four lanes of DNA are clipped and zipped together to form new genetic combinations.

The crystal structure of the Holliday junction was described by researchers from the University of Pennsylvania in 1998. Now, scientists use cryo-electron microscopy to analyze the structure of molecules, and structural biologist Cynthia Wolberger, Ph.D., who studies DNA’s chemical tags that switch genes on and off, has designed a festive version of the Holliday junction (pictured above). Understanding the Holliday junction and the other ways our DNA folds, bends and moves is key to deciphering complex issues of human health and disease.

Science Can Predict Who Will Stick to New Year Fitness Routine   

Vikram Chib, Ph.D., assistant professor of biomedical engineering, Johns Hopkins University School of Medicine and the Kennedy Kreiger Institute

Will a person stick to their New Year’s resolution of exercising more? Scientist Vikram Chib, Ph.D., studies the motivation for physical exertion. His research has shown how certain people may be more or less willing to exert effort. Using MRI studies, he has mapped the area of the brain responsible for these processes.

“We’re researching cognitive strategies that may help you override your current level for exertion effort, which may trick you into sticking to your workout routine,” he says.

Decorating Synthetic Cells for the Holidays

Takanari Inoue, Ph.D., professor of cell biology, Johns Hopkins University School of Medicine

Cell biologist Takanari Inoue, Ph.D., studies and creates synthetic cells, bubble-like entities that scientists can customize to research cell shape and movement — or, light up for the holidays.

Using molecular tools and dyes, Inoue and other scientists use festive holiday colors (red, green or anything in between) to differentiate parts of the cell. Mapping these cell processes is key to understanding how a synthetic cell can one day be used to deliver drugs or target certain germs.

“Changing parts of these synthetic cells from red to green using molecular tools and dyes isn’t just a festive trick — these colors help us differentiate between parts of a cell, and can indicate when a chemical on the cell membrane, for example, changes the shape of the cell.”

Difficult to Hear Conversation at a Crowded Holiday Party? Too Many Brain Cells May Be Firing at Once

Patrick Kanold, Ph.D., professor of biomedical engineering, Johns Hopkins University School of Medicine

Amid a cacophony of sound at a crowded holiday party, some — mostly older adults — may find it difficult to hear the conversation happening next to them. The reason for such common, age-related hearing problems, say researchers at Johns Hopkins, may be the inability to turn off wildly firing neurons in the brain.