Scientific American - September 2018

2 Scientific American, September 2018

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Microplastics Threat

Scientific American examines researchers’ efforts to

locate microplastics pollution and to stem the tide of

these particles entering the environment.

Go to http://www.ScientificAmerican.com/sep2018/microplastics

ON THE WEB

4 From the Editor

6 Letters

10 Science Agenda

We ignore racial and ethnic minorities in clinical trials

at our own peril. By  the  Editors

11 Forum

The sex-specific risks of Alzheimer’s point to targeted

interventions for men and women. By  Rebecca  Nebel

12 Advances

Extinct dogs were bone crushers. Fending off art-

eating fungi. A little oil could keep wine yeasts alive.

Toward personalized colon cancer screenings.

24 The Science of Health

The “Right to Try” law raises false hope for the very sick.

By  Claudia  Wallis

27 TechnoFiles

Think you know hearing aids? By  David  Pogue

100 Recommended

Seaweed as a resource. Racing to build an artificial heart.

Astrophysics powers military might. Driverless cars

make good. By  Andrea  Gawrylewski

101 Skeptic

Education and birth control are slowly making the

politics of abortion less relevant. By  Michael  Shermer

102 Anti Gravity

Examining the outsized influence of beavers on America.

By  Steve  Mirsky

103 50, 100 & 150 Years Ago

104 Graphic Science

Even with social media, we have only 150 real friends.

By  Mark  Fischetti and Jen  Christiansen

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