Science Friday

In the 1980s and 1990s, in the midst of rising crime rates and a nationally waning confidence in policing, law enforcement around the country adopted a different approach to addressing crime. Instead of just reacting to crime when it happened, officers decided they’d try to prevent it from happening in the first place, employing things like “hot spots” policing and “stop and frisk,” or “terry stops.” The strategy is what criminologists call proactive policing, and it’s now become widely used in police departments across the nation, especially in cities.

Critics and experts debate how effective these tactics are in lowering crime rates. While there’s some evidence that proactive policing does reduce crime, now public health researchers are questioning if the practice—which sometimes results in innocent people being stopped, searched, and detained—comes with other unintended physical and mental health consequences.

Samuel Walker, emeritus professor of criminology at the University of Nebraska Omaha and an expert in police accountability, reviews what led police departments to adopt a more proactive approach, while medical sociologist Alyasah Ali Sewell explains the physical and mental health impacts of stop-question-and-frisk policing.

If you live near the coasts, you may occasionally enjoy a good clam bake. Thousands of years ago, indigenous people in the Pacific Northwest were much the same, with clams forming an important part of the coastal diet and culture. In fact, inhabitants of the Pacific Northwest developed techniques for cultivating clams in constructed ‘clam gardens’ along the coastline.

A new study published this week in the Proceedings of the National Academy of Sciences found that those clam gardens were very successful, allowing the farmed clams to sustainably grow larger and more rapidly than untended clams, despite being heavily harvested. Dana Lepofsky, a professor of archaeology at Simon Fraser University and one of the authors of that study, joins Ira to describe the technology of the clam garden and what it might be able to teach us about modern sustainable aquaculture.

This week, a congressional hearing examined NASA’s plan to return humans to the moon by 2024—and some Appropriations Committee members didn’t seem particularly bullish on the idea. New York Representative José E. Serrano had this to say:

Since NASA had already programmed the lunar landing mission for 2028, why does it suddenly need to speed up the clock by four years—time that is needed to carry out a successful program from a science and safety perspective. To a lot of Members, the motivation appears to be just a political one—giving President Trump a moon landing in a possible second term, should he be reelected.

In this segment, Eric Berger, a senior space editor at Ars Technica, talks with Ira about the implications of that hearing.

Plus, as it rushes to meet that 2024 deadline, NASA this week unveiled a new spacesuit, tailor-made for strolling on the lunar surface. Amy Ross of NASA Johnson Space Center led the suit’s design, and she joins Ira here to talk about its capabilities—and why a puffy suit is still necessary, rather than a tighter design depicted and described in films like The Martian.

When the water rises, whether from heavy rains or rising seas, communities have a few options: reinforce flood-threatened homes, rebuild after the water recedes, or—in places where the threat of repeated floods and even more damage is increasing—leave.

And while leaving may feel synonymous with defeat, more cities and states are interested in encouraging people to leave risky floodplains—a process called managed retreat. FEMA offers a buyout program that usually involves offering homeowners money to encourage them to move elsewhere. New York Times reporter Christopher Flavelle and University of Delaware social scientist A.R. Siders describe some of the different ways cities and states have attempted the process: from Staten Island residents who took buyouts after flooding from Hurricane Sandy, to Louisiana’s new statewide plan for strategically targeting high-risk areas.

But how can managed retreat go wrong? New research in Science Advances from Siders and her colleagues has found that it’s often rich counties that apply for FEMA money, and they often use it for buying out poorer residents—leading to questions of whether resources or opportunities are being distributed equitably. Jola Ajibade, a geographer at Portland State University, expands these questions to the global scale: In Lagos, Nigeria, managed retreat offers no financial incentive to people being asked to leave. And in Manila, Philippines, people are offered new homes, but aren’t given a way to earn a livelihood.

Finally, with enough planning, can retreating retain the fabric of an entire community? In Sidney, New York, neighbors have been waiting eight years trying to move together to higher ground—and they’re still caught up in red tape. The planned relocation of a Native American community on Isle de Jean Charles, Louisiana, has hit roadblocks as well. But small Midwestern towns fleeing massive river floods have tried the same, and seem to be thriving decades later: see Soldiers Grove, Wisconsin, and Valmeyer, Illinois. Lehigh University anthropologist David Casagrande explains why collective community planning may end up being a key factor in retreat that leaves peoples’ lives and livelihoods most intact.

At a United Nations climate meeting in Poland last year, President Trump’s advisor on energy and climate change didn’t advance a forward-thinking plan to tackle climate change, but instead extolled the virtues of natural gas and even coal—one of the dirtiest fossil fuels. So, in the absence of meaningful federal policy on climate change, a grassroots effort by 435 U.S. mayors seeks to solve the climate problem, starting at the local level instead.

Emily Atkin, who writes the HEATED newsletter about the climate crisis, talks about that and other climate policy stories in the news, such as the lack of climate questions at the Democratic debate and the candidates’ views on punishing fossil fuel companies; Google donations that fuel climate science denial; and the Department of Agriculture’s lack of assistance for farmers dealing with increasingly extreme weather.

If you live and work in an urban area, you might think about the air quality outside your home or workplace. But what about the air quality inside the office? It turns out that on average, indoor environments have higher concentrations of potentially harmful substances, such as aerosols and volatile organic compounds (VOCs). While past research has focused on chemical emissions from building materials, cleaning supplies, and even furniture, air pollution researchers are increasingly looking at another source of toxic air: us.

New research from Purdue University to be presented at the American Association for Aerosol Research conference has found that the majority of indoor VOCs may be released by a seemingly innocuous source: human beings, their lunches and coffee breaks, and anything they may wear or bring to work. And many of these compounds, such as the terpenes released by peeling an orange, or the squalene released in human skin oil, react with ozone to form even more worrisome molecules.

If you’ve ever played the classic puzzle-like computer game Tetris, you know that it starts out slowly. As the seven different pieces (called “zoids” by the initiated) descend from the top of the screen, a player has to shift the pieces horizontally and rotate them so that they fit into a gap in the stack of pieces at the bottom of the screen, or “well.” In early levels, the pieces might take 10-15 seconds to fall. The speed increases at each level.

In world champion Tetris matches, players often start play at Level 18—in which pieces are on the screen for about a second. Wayne Gray, a professor of cognitive science at Rensselaer Polytechnic University, calls it a problem of “predictive processing and predictive action.” Champion-level expert players, he says, are able to take in the state of the gameboard and react almost immediately, without going through the mental steps of figuring out how to move the piece and rotate it that a novice player requires. “They can see the problem and reach a decision at the same time,” he said.

Gray and colleagues have attended the Classic World Tetris Championship tournament for three years, collecting data from expert players using a modified version of the game that collects keystrokes and eye-tracking data. He joins Ira to discuss what the researchers are learning about expert decision-making, and what he hopes to study at this year’s upcoming Tetris tournament.

The pharmaceutical industry has been on a 30 year mission to develop a drug to treat Alzheimer’s disease. The culprits behind the disease, they thought, were the amyloid plaques that build up in the brains of these patients. For many decades removing these plaques to treat Alzheimer’s was the goal.

But then drug after drug targeting amyloid failed to improve the symptoms of Alzheimer’s—the so-called “amyloid hypothesis” wasn’t bearing out. But drug companies kept developing and testing drugs that attacked amyloid from every angle—perhaps at the expense of pursuing other avenues of treatment.

This past summer, two more high profile clinical trials of drugs to treat Alzheimer’s failed. That brings the number of successful treatments for the disease, which affects 5.8 million Americans, to zero.

George Perry, professor of biology at UT San Antonio and Derek Lower, a drug researcher and pharmaceutical industry expert join Ira to explain what led pharmaceutical companies to doggedly pursue the amyloid hypothesis for decades, and whether or not they are ready to start trying something else.

Despite widely reported attacks on science, the vast majority of Americans continue to trust scientists, according to the latest survey from the Pew Research Center. Many listeners of Science Friday might take it as a given that we should trust science, but is that trust well-founded? Naomi Oreskes, history of science professor at Harvard University, argues that we should. In her new book, Why Trust Science?, she explains how science works and what makes it trustworthy. (Hint: it’s not the scientific method.)

Pacific Gas & Electric has generated confusion—not to mention outrage—with its power grid shutdowns. The situation continues for a second day in 34 California counties. On social media and phone calls to KQED’s Forum radio program, people throughout PG&E’s service area have asked how and why the investor-owned utility took this step. KQED reporters have some answers to some of the questions that have come in.

Why Is PG&E Turning the Power Off? Is This PG&E’s Fault?

Bottom line, PG&E doesn’t want to risk having its power lines start another fire, so it is pre-emptively turning the power off during this week’s dry, windy weather. The company made the decision based on information from its wildfire center, where meteorologists keep watch on fire conditions.

PG&E’s power lines have sparked many catastrophic wildfires in California, including last year’s Camp Fire in Butte County that caused 85 deaths, making it the deadliest U.S. wildfire in 100 years. PG&E lines started more than a dozen fires in 2017. Less than a month ago, the company agreed to pay billion in a settlement with victims of the recent fires.

The shutoffs are part of its wildfire mitigation plan, mandated by the state and agreed to by the California Public Utilities Commission, the state’s top power regulator. — Kevin Stark

Who Made This Decision? When Did They Make It?

If past practice tells us anything, PG&E has been making and remaking this decision, with the help of its meteorological team, over several days. The utility says it considers weather, fuel and other conditions and observations, as well as the need for notice by state and local parties, when it decides to implement shutoffs. As we’ve seen over the last few days, the planned outage times can change with shifting conditions.

The fact is, there’s nothing new about turning off power lines when conditions get risky: San Diego Gas and Electric, with the permission of the CPUC, has mitigated fire risk this way since 2012. What is new are the guidelines PG&E filed just a year ago for its public safety power shutoff procedures.

For the last couple of years, the CPUC has required investor-owned utilities to describe their processes for arriving at decisions like the one affecting nearly three dozen California counties right now. PG&E shut off power two times last year; the last time PG&E called a public safety power shutoff, for two days in June, it affected about 22,000 customers in the North Bay and the Sierra foothills, including Butte County and Paradise. — Molly Peterson

Read more questions and answers on Science Friday.

Cartilage is the connective tissue that provides padding between your joints. As we age, the wearing down of cartilage can lead to different types of arthritis. It’s been long believed that once humans lose cartilage, it can never grow back. Now, a team of researchers investigated this idea, and found that the cartilage in our ankles might be able to turnover more easily compared to our hips and knees. Their results were published in the journal Science Advances. Rheumatologist Virginia Byers Kraus, who was an author on the study, discusses how human cartilage might be able to regenerate and what this means for future treatments.

Flour, salt, yeast and water are the basic ingredients in bread that can be transformed into a crusty baguette or a pillowy naan. But what happens when you get a sticky sourdough or brick-like brioche? Chef Francisco Migoya of Modernist Cuisine breaks down the science behind the perfect loaf. He talks about how gluten-free flours affect bread structure, the effects of altitude and humidity on dough and how to keep your sourdough starter happy. Plus, amateur baker and “Father of the Xbox” Seamus Blackley describes how he baked a loaf of bread from an ancient Egyptian yeast.

The Bureau of Land Management issued an environmental impact statement last month that examines the effects that oil development will have on the Arctic National Wildlife Refuge. Buried deep in the appendix of the report was this BLM response to a public comment:

"The BLM does not agree that the proposed development is inconsistent with maintaining a livable planet (i.e., there is not a climate crisis). The planet was much warmer within the past 1,000 years, prior to the Little Ice Age, based on extensive archaeological evidence (such as farming in Greenland and vineyards in England). This warmth did not make the planet unlivable; rather, it was a time when societies prospered."

The comment alludes to the so-called “Medieval Warm Period,” which is commonly referenced by climate change deniers to justify their beliefs. The BLM has since said the comment had no bearing on the scientific conclusions contained elsewhere in the report. Adam Aton, a climate reporter at E&E News, joins Ira to talk about the report, and what fossil fuel development in the Arctic might mean for local wildlife and the planet.