The Conversation

How active are the microorganisms in your yogurt? We created a new tool to study probiotic activity — and made it out of cardboard

Written by Carlos D. Garcia, Professor of Chemistry, Clemson University

Fermented foods can be a good source of probiotics. Yulia Naumenko/Moment via Getty Images

Humans have been fermenting food and drinks — everything from kimchi and yogurt to beer and kombucha — for more than 13,000 years.

Fermentation – a natural process that uses microorganisms to create alcohols and acids from carbohydrates...

Teaching positive psychology skills at school may be one way to help student mental health and happiness

Written by Kai Zhuang Shum, Assistant Professor of School Psychology, University of Tennessee

Gratitude, kindness and optimistic thinking can help kids feel a bit better.Wipada Wipawin/iStock via Getty Images Plus

Youth mental health has worsened significantly over the past decade, but new interventions that teach positive psychology concepts in school may help.

American young people are reporting historically high levels of hopelessness,...

Why are some black holes bigger than others? An astronomer explains how these celestial vacuums grow

Written by Jaclyn Champagne, JASPER Postdoctoral Researcher, University of Arizona

Black holes use gravity to pull matter into them. NASA/Chandra X-ray Observatory/M.Weiss via AP

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com.

Why are there small and big black holes? Also, why are some black holes invisible and others have...

Do you hear what I see? How blindness changes how you process the sound of movement

Written by Ione Fine, Professor of Psychology, University of Washington

Sighted people would have a hard time crossing the street by sound alone.Maskot/DigitalVision via Getty Images

Almost nothing in the world is still. Toddlers dash across the living room. Cars zip across the street. Motion is one of the most important features in the environment; the ability to predict the movement of objects in the world is often...

More vulnerable people live in Philadelphia neighborhoods that are less green and get hotter

Written by Farzad Hashemi, Assistant Professor in Architecture, The University of Texas at San Antonio

Philadelphia's neighborhoods are green and not so green.Marli Miller/UCG/Universal Images Group via Getty Images

The ways an urban neighborhood is built and the characteristics of the people who live there are both related to how hot it gets. That is the result of our study, published by the Journal of Buildings.

If you have ever noticed that some...

A bottle of scotch recently sold for $2.7 million – what's behind such outrageous prices?

Written by Hovig Tchalian, Assistant Professor of Entrepreneurship, University of Southern California

In November 2023, a bottle of Macallan Scotch whisky fetched the highest price of all time for a bottle of wine or spirits.Wiktor Szymanowicz/Future Publishing via Getty Images

When a rare bottle of Scotch whisky sold for US$2.7 million in November 2023, I was stunned, but I wasn’t surprised.

The whiskey market has been booming for some time.

Bo...

After 50 years of global effort to abolish torture, much work remains

Written by Christopher Justin Einolf, Associate Professor of Sociology, Northern Illinois University

A group of Spanish people have filed a lawsuit seeking compensation for torture they and others experienced under the Franco regime from 1939 to 1975.David Zorrakino/Europa Press via Getty Images

The world’s first conference on the abolition of torture drew more than 300 delegates representing over 70 countries and international...

Students could get more sleep and learn better if school started a little later

Written by Joanna Fong-Isariyawongse, Associate Professor of Neurology, University of Pittsburgh

About 58% of middle schoolers and 73% of high schoolers do not get enough sleep.JackF via iStock / Getty Images Plus

Nearly three-quarters of high school students do not get enough sleep on school nights, according to the Centers for Disease Control and Prevention.

The National Sleep Foundation recommends that teens sleep for eight to 10 hours per...

Paying people to replant tropical forests − and letting them harvest the timber − can pay off for climate, justice and environment

Written by Jefferson S. Hall, Staff Scientist and Director, Agua Salud Project, Smithsonian Institution

Planting trees on deforested lands in Panama.Jorge Aleman/Smithsonian Tropical Research Institute

Tropical forest landscapes are home to millions of Indigenous peoples and small-scale farmers. Just about every square meter of land is spoken for, even if claims are not formally recognized by governments.

These local landholders hold the key to a...

100 years ago, the KKK planted bombs at a U.S. university – part of the terror group's crusade against American Catholics

Written by William Trollinger, Professor of History, University of Dayton

A KKK rally in Dayton, Ohio, on Sept. 21, 1923.Dayton Metro Library

It was Dec. 19, 1923 – 100 years ago. The first day of Christmas break at the University of Dayton, with fewer than 40 students still on campus.

At 10:30 p.m., the quiet was shattered by a series of explosions, as 12 bombs went off throughout campus. Frightened students...