We are rounding up your questions about roads. What confounds you about traffic, or how interstates are laid out? Are there certain road design elements that ignite your road rage? Tell us about it: we’ve got a traffic engineer in the passenger seat this week, ready to answer your questions. Call us at (877) 4-SCIFRI or 877-472-4374.In this episode, utterances like “um,” “wow,” and “mm-hmm” aren’t just fillers—they keep conversations flowing. Also, new research suggests the artificial sweetener saccharin could kill antibiotic resistant bacteria.Huh? The Valuable Role Of InterjectionsListen carefully to a spoken conversation and you’ll notice that the speakers use a lot of little quasi-words—mm-hmm, um, huh? and the like—that don’t convey any information about the topic of the conversation itself. For many decades, linguists regarded such utterances as largely irrelevant noise, the flotsam and jetsam that accumulate on the margins of language when speakers aren’t as articulate as they’d like to be.But these little words may be much more important than that. A few linguists now think that far from being detritus, they may be crucial traffic signals to regulate the flow of conversation as well as tools to negotiate mutual understanding. That puts them at the heart of language itself—and they may be the hardest part of language for artificial intelligence to master.Read the rest of this article on sciencefriday.com.A Sweet New Treatment For Antibiotic Resistant Infections?Researchers have discovered that the artificial sweetener saccharin has powerful antimicrobial properties. A new study published in EMBO Molecular Medicine suggests that saccharin can actually kill antibiotic resistant bacteria by interfering with DNA replication and cell division. The researchers also concluded that, with the help of traditional antibiotics, saccharin could even be used as an effective wound treatment.Host Ira Flatow talks with study author Dr. Ronan McCarthy, professor in biomedical sciences and director of the Antimicrobial Innovations Centre at Brunel University of London.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.