Also, Nigeria’s upcoming election and healthcare protests in China.Workers reinforced a checkpoint in Kyiv with sandbags.Emile Ducke for The New York TimesOne year of warUkraine is bracing for potential Russian attacks timed to the anniversary of the war today. President Volodymyr Zelensky of Ukraine has warned of a symbolic “revenge” assault from Russia around the one-year mark of Moscow’s invasion. Schools across Ukraine are holding classes remotely, people have been advised to avoid large gatherings and additional security measures are being put in place. We have updates here.One year on, virtually no one in Ukraine has avoided the violence, destruction and bloodshed of the war, which has killed tens of thousands, left millions homeless and turned entire cities into ruins. But the foreboding that gripped Ukraine in the days before the invasion has long faded.Now, many people in Ukraine said that they had found strength in the shared sacrifice and the collective struggle for survival. Some have become accustomed to the air-raid sirens and warnings. One 30-year-old Ukrainian said those things had become a part of everyday life, “like brushing my teeth.”A global look: The U.S. tried to isolate Russia by imposing sweeping sanctions along with its Western partners. But the rest of the world has taken a more neutral approach to the war, including India and China, as our graphic shows.The latest on weapons: Poland said that it was close to finalizing a deal worth $10 billion to buy additional U.S.-made HIMARS rocket launchers and related equipment, as part of a rapid military buildup. As the West scrambles to find munitions for Ukraine’s Soviet-era weapons, it is turning to arms factories across Eastern Europe.China: Janet Yellen, the U.S. treasury secretary, warned Beijing against helping Russia evade sanctions, at a meeting of G20 finance ministers in India. She also said that the U.S. planned to unveil additional sanctions on Russia.Officials sorted voter cards in Lagos last month, ahead of the election.Pius Utomi Ekpei/Agence France-Presse — Getty ImagesNigeria votesNigerians head to the polls tomorrow to choose a new president in the most wide-open race in years. The presidential candidates for the two major parties, which have alternated power for over two decades, are facing a surprise, third-party challenger.In the lead-up to voting day, a decision by Nigeria’s government to replace its currency caused chaos. Voters are furious at the governing party over a shortage of new bank notes, and protests could disrupt voting in parts of the country.Lynsey Chutel, our Briefing writer based in Johannesburg, spoke with our West Africa bureau chief, Ruth Maclean, who is in Abuja to cover the election. Here’s what Ruth said about what’s at stake.“When I interviewed Peter Obi, one of the three main candidates, the other day, he described this as an ‘existential election.’ I think that’s how many Nigerians feel, particularly young Nigerians who were involved in the EndSARS movement a couple of years ago, protesting against police violence, but also against everything they saw going wrong in Nigeria. Many of them have left or are trying to leave the country. If their chosen candidate wins, maybe some will stay, or come back,” Ruth said.As populations in wealthy countries grow older, Africa’s median age is getting younger. In Nigeria, half of the population of more than 200 million is 18 and under.“If Nigeria is safe and prosperous, it brightens life for a whole generation of Africans,” Ruth said.A protest against health care cuts in Wuhan last week.Keith Bradsher/The New York TimesHealth care protests in ChinaThousands of seniors in China are protesting abrupt cuts to their health insurance. The changes were enacted by local governments, and highlight their struggle to recover from the costs of implementing the central government’s expensive “zero Covid” policies for nearly three years.One of the most immediate problems is that municipal insurance funds are running out of money. To free up cash, municipalities have started contributing much less to personal health accounts, the insurance that middle-class people use to pay for medicine and outpatient care. Seniors are most vulnerable to the changes, which include higher costs and reduced benefits.Protests have taken place in the northeastern city of Dalian, in Guangzhou, and in Wuhan in central China, where the Covid pandemic began at the end of 2019. Wuhan’s hospitals responded with an effective but expensive effort to contain the outbreak, and are now implementing some of the sharpest cuts to personal health accounts.Context: The cuts are a symptom of China’s overlapping economic struggles. The country is aging rapidly, and more retirees mean more health care needs. Yet the main source of municipal revenue has shriveled as real estate developers buy less public land because of a housing shakeout.THE LATEST NEWSAsia PacificRescuers at the site of the mine collapse in northern China’s Inner Mongolia.CCTV, via Associated PressRescuers are working to save 53 coal miners who are missing after a mine collapsed in northern China.The European Commission banned TikTok from most of its employees’ phones, citing security concerns.The temporary suspension of Peter Bol, an Australian Olympic runner, over doping allegations has opened a national debate over testing procedures.Around the WorldLawmakers in Mexico gutted the country’s election watchdog, a change that comes ahead of next year’s presidential contest.Jared Kushner and Ivanka Trump were subpoenaed by the special counsel investigating Donald Trump.The U.S. nominated Ajay Banga, the former chief executive of Mastercard, to lead the World Bank.Other Big StoriesMaternal mortality rates have fallen in many countries across Asia, but have increased in the U.S. and Europe, the W.H.O. reported.Turkey is scrutinizing Turkish builders after the recent earthquake that killed more than 43,000 people in the country.A British pilot program of a four-day workweek won converts: 92 percent of participating companies plan to continue with the approach.The Week in CultureHarvey Weinstein was sentenced to 16 years in prison for sex crimes in Los Angeles.Alec Baldwin pleaded not guilty to involuntary manslaughter for the fatal shooting of a cinematographer on a film set.The singer R. Kelly was sentenced to 20 years in prison for child sex crimes.A Morning ReadThe new drinks are branded Oleato, which can mean oiled or greaseproof in Italian.Valentina Za/ReutersStarbucks is testing out a new ingredient that it believes will draw the Italian masses to its coffee: olive oil. A golden foam espresso martini is one of five oily options.ARTS AND IDEASChatGPT’s scary banalityWhen the movies imagined A.I., they pictured the wrong disaster, our critic A.O. Scott writes. Instead of the chilling rationality of HAL in “2001: A Space Odyssey,” we got the drearier, very human awfulness of Microsoft’s Sydney. Because when real chatbots finally came about, they learned from what humans have expressed online, which can often be deceitful, irrational and plain old mean.“We’re more or less reconciled to the reality that machines are, in some ways, smarter than we are,” Scott writes. “We also enjoy the fantasy that they might turn out to be more sensitive. We’re therefore not prepared for the possibility that they might be chaotic, unstable and resentful — as messy as we are, or maybe more so.”In China: Tech companies making chatbots are facing hurdles from the government.And in the arts: Science fiction magazines are being flooded with stories written by chatbots. They’re “bad in spectacular ways,” one editor said.PLAY, WATCH, EATWhat to CookColin Clark for The New York TimesFor a weekend project, make Swedish cardamom buns.What to Read“Win Every Argument” and “Say the Right Thing” offer different approaches to talking to others.What to WatchIn “Yanagawa,” by the Chinese filmmaker Zhang Lu, two brothers reconnect over a lost love.HealthLearn about the wild world inside your gut.Now Time to PlayPlay the Mini Crossword, and a clue: Bashful (three letters).Here are the Wordle and the Spelling Bee.You can find all our puzzles here.That’s it for today’s briefing. Have a lovely weekend! — Amelia and LynseyP.S. Will Shortz, our puzzle editor, talked to The New Yorker about his life in crosswords.“The Daily” is on a U.S. Supreme Court case about social media.If you ever want to reach me, I’m available at briefing@nytimes.com. Thanks! More