A new study found that more than two million Russian and Ukrainian troops have been killed or wounded since Russia invaded four years ago. It’s a bleak accounting of a war that continues to grind on.

The count is according to the Center for Strategic and International Studies, which uses data from the American and British governments because both Ukraine and Russia are known to shield their true casualty counts.

The study found that Russia, which sent many more troops to the battlefield, has borne the heavier toll: Ukraine has suffered 125,000 to 150,000 deaths, while about 450,000 Russian troops have been killed. Russia’s toll is roughly four times the number of U.S. fatalities in all conflicts combined since World War II.

Recently, Ukraine has ramped up its attacks. “Russia is facing, by far, its darkest period of the war,” wrote one of the authors of the study, which found that it lost more territorial control in Ukraine than it gained this spring.

Scientists create a cell with most of the hallmarks of life

A team of researchers at the University of Minnesota announced a breakthrough in the effort to create life from scratch. They mixed a large number of chemicals in a lab to make a synthetic cell that eats, grows and reproduces, passing along its genetic material to future generations. They called it a SpudCell.

Is it alive? That’s a hard question to answer because there’s no one definition for what qualifies as living. The scientists behind the development do not claim to have created life, though SpudCells have most of the hallmarks of life. “It does what cells do,” one biologist said.

Scientists hope the cells can help answer questions about life, and someday be engineered to do things that natural ones can’t, like making new kinds of medicine.

Trump debuts the new Air Force One, a gift from Qatar

President Trump flew to North Dakota this morning to visit the Theodore Roosevelt Presidential Library. It was his first trip aboard the newest addition to the presidential fleet: a red, white and blue Boeing 747-8 that was given to the U.S. last year by the Qatari royal family. See it take off.

The luxury jet, worth about $200 million, was among the largest gifts a foreign government has ever given to the U.S. Under the terms of the deal, it would be donated to Trump’s presidential library when he leaves office, potentially making it available for his personal use. Critics and lawmakers suggested that it was an attempt by Qatar to buy influence.

Republicans lead in crucial Senate races

Democrats are hoping that the president’s unpopularity will help them retake control of the Senate after this year’s midterm elections. But they are still facing an uphill battle, our new polls found.

In the six closest Senate races for seats currently held by Republicans, Democrats are ahead only in North Carolina and Maine. They need to win at least four to secure a majority. Our political analyst Nate Cohn explains how to interpret the results.

U.S. enters the World Cup knockout stage with high hopes

At 8 p.m. Eastern tonight, the U.S. men’s national team will play Bosnia and Herzegovina in its first win-or-go-home game of this year’s World Cup. Many soccer experts anticipate that the Americans will win, though Bosnia’s defense is very capable. Soccer pros told us what to expect.

If the Americans win the entire tournament — as few expect — NASA said it would try to send a soccer ball to the moon.

For more on the World Cup:

Sandra Boynton’s work shows the depth of children’s literature

Since she published her first masterpiece, “Hippos Go Berserk!,” 49 years ago, Sandra Boynton has sold more than 90 million picture books. Her success has something to do with the adorable animals she illustrates and the silky rhymes she writes.

But more important, Boynton really understands children and child care with enough depth to connect with both kids and adults — the latter of whom will inevitably read her work time and time again. We put together a guide to her best books.

Ping-Pong like you’ve never seen it

Table tennis began as a Victorian-era parlor game in which players used the lids of cigar boxes as paddles. It’s also been a Cold War diplomacy tool, an Olympic sport and the backdrop for an Oscar-nominated movie.

In that spirit of reinvention, an arts group has set up six public, artist-designed Ping-Pong tables on New York City’s Rockaway Beach. One has a giant tentacle sticking through the middle of the table; another features holes where you might want to hit the ball. “Everyone will be bad, so that might make it inviting to more people to try it out,” one artist said. Take a look.

Have a goofy evening.

Thanks for reading. I’ll be back tomorrow — Matthew

Eli Cohen was our photo editor.

We welcome your feedback. Reach us at evening@nytimes.com.