China strongly condemns the extremely irresponsible and provocative remarks made by NATO Secretary General Jens Stoltenberg that were characterized by a Cold War mentality, blame shifting, and shirking responsibility on the Ukraine issue, Chinese Foreign Ministry spokesperson Lin Jian said on Friday.

On Thursday, Stoltenberg reiterated at the closing press conference of the NATO summit that NATO defines China as a "decisive enabler" of the Russia-Ukraine conflict, and claimed that China has adopted more aggressive actions in its Hong Kong Special Administrative Region and the South China Sea, Taiwan and neighboring countries, and is conducting a large-scale military build-up in a non-transparent fashion.

Lin noted that Stoltenberg's remarks were filled with ideological prejudice, reversing right and wrong, maliciously attacking China's political system, openly interfering in China's internal affairs, and maliciously distorting China's domestic and foreign policies.

Stoltenberg's remarks also shift blame and shirk responsibility on the Ukraine issue, misleading the international community's perception of China's normal military development and its relations with outside countries. China expresses strong dissatisfaction and firm opposition to this, said Lin.

Lin said that Stoltenberg has repeatedly ignored facts and China's repeated representations, using various occasions to smear and attack China, promoting the "China threat" narrative, and inciting anti-China sentiment. His intentions to cooperate with certain forces in suppressing and containing China has been fully exposed.

Such clumsy performances cannot help but arouse the world's vigilance and fully demonstrate that NATO, as a remnant of the Cold War and a product of bloc confrontation and group politics, only creates risks and challenges to world peace and stability, Lin said.

Lin said that certain Western politicians, who are nearing the end of their political careers, should not to attempt to leave a legacy through fanning the flames, provoking trouble, and shifting blame onto others.

China will firmly follow the path of peaceful development, injecting stability and positive energy into world peace and stability through its own development and international cooperation. At the same time, it will firmly safeguard its own sovereignty, development, and security interests. Viewing China as an "imaginary enemy" will ultimately lead NATO to reap what it has sown, Lin noted.

China on Thursday also voiced strong opposition and lodged stern representations on Thursday with NATO after it issued a direct warning to China for the first time regarding the so-called support to Russia in the Ukraine crisis.

Leaders of NATO's 32 members held a three-day summit in Washington, DC from Tuesday to Thursday. And for the third year in a row, the leaders of New Zealand, Japan and South Korea attended the summit as observers.

According to reports, Japanese Prime Minister Fumio Kishida held talks with South Korean President Yoon Suk-yeol on Wednesday, and both sides expressed hope that Japan and South Korea can maintain close cooperation with NATO.

Lin said at the Friday press conference that NATO, led by the US, as a remnant of the Cold War and the world's largest military alliance, claims to be a regional and defensive organization while continuously creating regional tensions and promoting bloc confrontation. It seeks excuses to strengthen its ties with countries in the Asia-Pacific region, which has aroused high vigilance among regional countries.

The Northeast Asia region, having suffered from the ravages of war, military standoff, and bloc confrontation, deeply understands the value of peaceful coexistence, solidarity, cooperation, and mutual benefit. The current state of peace, cooperation, stability, and prosperity in the Asia-Pacific region, including Northeast Asia, is the result of the joint efforts of regional countries, said Lin.

The Asia-Pacific does not need military alliances, nor does it need "small circles" that provoke great power confrontation and instigate a new Cold War, said the spokesperson.

We hope that regional countries will adhere to the path of Asia-Pacific cooperation, play a constructive role in maintaining and promoting peace, stability, and development in the region and the world, and refrain from acting as the vanguard for NATO's expansion to Asia-Pacific, Lin said.

Editor's Note:

A violent incident at a concert venue on the outskirts of Moscow resulted in the death of at least 137 individuals and left over 100 injured. The assailants used automatic firearms during the incident and utilized an inflammable substance to start a blaze.

Analysts have noted that this is one of the most severe terrorist attacks Russia has faced in over a decade.

Russian President Vladimir Putin announced the capture of all four assailants responsible for the onslaught, stating that everyone involved in the act, from those who carried it out to those who organized and funded it, will face consequences.

More than 30 hours after the tragic event, those who experienced the ordeal are still deeply shaken. Several Chinese residents in Russia have shared their close encounters and emotions regarding the terror attack with the Global Times.

This story is part of the Global Times' series "Witness to history," which features first-hand accounts from witnesses who were at the forefront of historic moments. From scholars, politicians, and diplomats to ordinary citizens, their authentic reflections on the impact of historic moments help reveal a sound future for humanity through the solid steps forward taken in the past and the present.
Moscow's streets on Friday night were bustling with traffic and crowded with people preparing for the upcoming weekend.

For Chinese student Chen Yiming, this was supposed to be a good opportunity to unwind in the Russian capital.

Chen is a student at Saint Petersburg State University. On that Friday, he returned from a short trip to Armenia and arrived in Moscow, ready to transfer back to Saint Petersburg.

He visited Crocus City Hall, a spectacular complex stretching 1.2 kilometers with four floors housing restaurants, entertainment, and shopping, bustling with activity in Krasnogorsk, in the northwest of Moscow. Chen intended to enjoy a meal at a restaurant on the fourth floor, unaware that the wheels of fate were already turning.

As he browsed the menu, pondering his meal choice, a deafening explosion shattered the peace, too loud to ignore, unsettling everyone around.

Chen sensed it might be a drone attack. With Ukraine's repeated drone strikes on Moscow, this thought was not unfounded.

However, the continuous sound of gunfire soon made him realize it was not a drone but actual shooting. Panic spread, and the crowd in the mall began to scatter in chaos, with no one knowing what exactly was happening or where to flee.

Following the crowd, Chen rushed outside, filled with fear and uncertainty, witnessing people falling, screaming, and some lying on the ground. He followed the crowd toward a nearby bridge, thinking it might be safer.

"The gunfire lasted about 10 minutes," he recalled.

About ten minutes later, through social media, Chen knew the truth - the mall's concert hall had been attacked.

After the initial shock, the gravity of the situation finally donned on him, as such terror attacks are extremely rare in Russia, only seen in movies.

Police quickly arrived at the scene, about 10 to 20 minutes after the incident. The sound of helicopters added to the tense atmosphere.

Chen took the opportunity to leave, fortunately catching a free taxi ride.

Chen was not the only Chinese person close to the attack.

A Chinese person surnamed He from North China's Hebei Province, was also right in the concert hall and witnessed the attack.

He, a pianist who won international competitions for China, had been invited to perform at the concert. He was sitting at the back, listening to the performance, when armed attackers disrupted the venue, causing chaos.

He immediately hid under his seat, trying to stay silent amid the turmoil and screams. He saw the attackers' entry through the gaps in the seats, hearing live gunfire for the first time in his life, according to a report published by Chongqing News.

After a period of chaos and tension, police took control, and he was then safely escorted back to his school.

Tragically, his Russian friend, a girl, was not so fortunate. It is reported that the girl left the concert hall to go to the restroom midway through the event, where she unfortunately encountered the armed assailant and tragically lost her life.

Other survivors also recounted their escape experiences through various means.

One survivor said that the security staff directed people into a boiler room where water tanks or fire hose boxes were stored, with about 50 people hiding there, The Beijing News reported.

The survivor said that they used water from the fire hydrants to wet their clothes to cover their faces, sat on the floor to remain as low as possible. He recalled that subsequently, rescuers broke into the boiler room, the survivors inside responded, and they all fled together.

Another survivor mentioned that she was injured and fell to the ground, managing to survive by playing dead. She waited until the terrorists left before crawling out of the concert hall.

Russian President Vladimir Putin said Saturday all four gunmen in the Moscow terrorist attack were arrested. Putin, addressing the nation, said that all those responsible for the deadly attack would be punished. He also ordered that March 24 be a nationwide day of mourning.
Bonding of community

In the southwest part of Moscow, Xu Wenteng was live-streaming on TikTok as usual, sharing daily activities as a Chinese Volunteer Union in Russia.

However, that night turned out to be so different.

During the live stream, Xu, the president of the association, received a message about a terrorist attack in western Moscow. The sudden news disrupted the live stream's flow and Xu's peace of mind.

His live stream quickly turned from routine to a hub of urgent news update. With the help of the Chinese community in Moscow and Russian friends, he began to report the latest developments of the incident to his audience.

That night, his live stream became an information center, with the Chinese residents in Russia and netizens sharing information, helping each other understand the situation.

Despite the attack happening far from his residence in the southwest district, he immediately worried about his niece and family, and fortunately was relieved to learn of their safety.

The familiarity of the attack location deeply affected Xu. "It was a gathering of young people," he told the Global Times.

Nevertheless, during the live stream, he used his two-decade experience in Moscow to advise calmness, especially when the situation was unclear, recalling past incidents and emphasizing staying informed through official news sources.

Even though the intense discussion temporarily choked his live stream, Xu continued to communicate with the Chinese community in Russia through various channels, sharing real-time information and offering assistance.

After the attack, he saw increased security in Moscow, with more police at important sites like Red Square, but he remained vigilant, believing that the act was organized and deliberate.

Xu knew that such events could shock recent Chinese arrivals and those new to Moscow. He specially conveyed reassurance to anxious parents in China, urging them to avoid spreading panic and unfounded rumors, and to not spread anxiety to their children in Russia.

China strongly condemns terrorist attacks, and firmly supports Russia in safeguarding its national security and stability, a Chinese Foreign Ministry spokesperson said on Saturday.

The spokesperson said China opposes all forms of terrorism, strongly condemns terrorist attacks, and firmly supports Russia in safeguarding its national security and stability.

Preciousness of national stability

Chen spent the following Saturday indoors in central Moscow, only going out to eat. He is still feeling tense but not seeking embassy assistance, considering his situation manageable.

For safety, his university in Saint Petersburg decided to suspend classes for the next week.

The attack also caused flight prices to spike. The prices of direct flights from Moscow back to China surged over the weekend. The direct flight tickets from Moscow to Beijing on March 24 were all priced at more than 10,000 yuan ($1,383), with only a small number of tickets available. Air China's Moscow-Beijing flight had only first-class tickets priced at over 50,000 yuan left, media said.

However, Chen had no immediate plans to return home. Despite the foreign environment and the sudden panic and chaos, he felt a growing inner calmness, choosing to stay in Russia to continue his studies and life.

Survivor He who escaped the concert hall has also resumed his studies at school, taking Russian language courses online. He, too, expressed his intention to stay in Russia to continue his education and to prepare for his dream of participating in the Chopin Piano Competition.

Moscow's streets, once lively, were shrouded in a thin layer of gloom. Following the attack, the city center, including the Red Square, was closed on Saturday, but tour groups still visited nearby, and some tourists took photos from behind the fences.

In a video clip Xu sent to the Global Times, a group of middle-aged and elderly tourists shouted together in front of the Saint Basil's Cathedral on Red Square, "Today is March 23rd, Moscow is very safe."

While going out, Chen noticed a significant reduction in traffic and pedestrians compared to the previous day's hustle and bustle, with increased police patrols. Some public places were closed, while some others are still open.

He remembered the scenes of helplessness, fear, and desperate attempts to escape during the attack, haunting his thoughts. However, as time passed, his fear was gradually replaced by rationality.

On Sina Weibo, he wrote, "The explosion last night is still fresh on my mind, reminding me of life's unpredictability and the preciousness of national stability and unity. I hope everyone stays healthy and safe."

Many netizens also expressed their concerns for his safety and wished him an early return home.

On Sunday morning, in a WeChat group of the Russian Chinese community, an elderly Chinese resident in Moscow posted a warning about the possible still-at-large terrorists, advising caution and reduced outings.

This message brought some reassurance to the community, knowing they were not alone and unsupported.

Xiang Piao Piao's stock price soared on Monday and hit the daily up limit after netizens found one of its products sold in a store in Japan have cup sleeve satirizing Japan's handling of nuclear-contaminated wastewater.

The Chinese milk tea brand has reportedly seen a 400 percent surge on its live streaming sales in China as millions of netizens bought the products from Saturday to Sunday.

A Chinese netizen discovered that MECO fruit tea, a drink under the brand of Xiang Piao Piao, sells products in a store in Japan with slogans on their cup sleeves showing "the ocean is not Japan's sewer" and "0.1 percent of the land pollutes 70 percent of the ocean." The picture was then exposed on Chinese media social platform.

Tens of thousands of simultaneous viewers visited Xiang Piao Piao's  live stream over the weekend after the matter went heated, in which three of the six items were sold out during the live. The daily sales of its store have skyrocketed from 2,500 yuan ($346) to 1 million yuan, according to media reports. 

The cup sleeves have also been out of stock as the demand is increasing, and it will be replenished at a later date, according to the anchor of the event. 

The official Weibo account of Xiang Piao Piao also released a statement on Saturday saying that "our staff are awesome" after its action triggered heated discussion on Chinese social media platforms. According to media report, the president of Xiang Piao Piao said during the live stream on Sunday that he would award 100,000 yuan to the related employees and donate all the income from the live stream from 8 pm to 12 am that night to the Environmental Protection Foundation.

The hotline staff from Xiang Piao Piao said that it was a personal behavior of the employees, not an initiative of the company, according to the 21st Century Business Herald. The Kyowa store in Okubo of Japan also told the media that the store has not sold drinks with such cup sleeves.

According to previous reports, the Tokyo Electric Power Company (TEPCO) started to dump the fifth batch of Fukushima nuclear-contaminated water into the ocean on April 19. In Japan's fiscal 2024, which ends in March 2025, TEPCO plans to release a total of 54,600 metric tons across seven rounds, the Japan Times reported.

US Congress has reportedly reached a deal on how much the US government will spend in 2024 in a significant move toward avoiding a shutdown, but it doesn't necessarily defuse the threat altogether, Chinese observers said.

The US government shutdown risk reflects Washington's "declining fiscal management and governance ability," which may negatively impact US economy and the financial market, they said
.
The deal would establish an overall spending level of $1.59 trillion in fiscal 2024, US media outlet NBC News reported on Monday, noting that the threat of a potential US government shutdown isn't completely ruled out yet, as Congress still needs to allocate the money, write the bills and approve them.

During the last five decades, there have been 21 US federal government shutdowns. A government shutdown would lead to the suspension of nonessential federal functions and result in millions of federal employees not receiving pay.

The repeated US federal government shutdowns and lingering threats reflect that the US government's relatively weak governance and fiscal management ability, although for many times, the US government is able to solve crises at the last minute, Huo Jianguo, vice chairman of the China Society for World Trade Organization Studies, told the Global Times on Monday.

The continuous increase in US government debt will produce negative effect on the US economy in the long run, as Washington needs to pay more interest on its huge debt, Dong Yun, director of the Research Center for International Political Economics of the National Institution for Finance and Development, told the Global Times on Monday.

"The US' fiscal sustainability will continue to weaken, which may increase US financial sector instability and spill over to impact global markets," Dong said.
Dong said it's a general trend that many countries are diversifying their foreign assets and increasing holdings of gold, but only by promoting reforms to the international monetary system and boosting the development of emerging market economies can there be "more choices for a country's holdings of foreign assets."

Aside from shocks to the US itself, repeated government shutdowns will impact the US' influence in global affairs and accelerate the decline of US dollar hegemony in the world, Huo said.

Huo said that the continuous issuance of US Treasuries will make it difficult for the US government to repay its debts, which will reduce the reliability and credibility of US dollar-denominated assets.

The US' aggressive interest rate hikes to tame inflation has brought spillover effects to other countries, especially developing countries, making many economies rush to diversify payment using local currencies and increasing holdings of gold in 2023.

China's gold reserves reached 71.87 million ounces at the end of December, marking the 14th consecutive month of increase, latest data from the People's Bank of China showed.

The Beijing Design And Art Expo, one of the key events of the Beijing International Design Week, opened on Thursday at the China National Agricultural Exhibition Center in Beijing.   
Taking the theme Rejuvenating Life, the expo covers three distinctive units: Beauty of Technology, Beauty of Taste and Beauty of Life. 

With 17,000 square meters of exhibition area, more than 100 exhibitors, and more than 10 events, the expo brings together high-quality design content from around the world. It gathers innovative designs in the fields of culture, tourism, technology, art, food, home, clothing and cultural creativity, leading the public to explore the potential and possibilities of design in the future, and to experience the industry trends and lifestyle brought by the expo.

The technology section focuses on the innovation of emerging digital culture and tourism industry technology and content, and activates new formats with cross-border cooperation mode.

Visitors can enjoy the immersive experience Dream Forest, the stunning ball screen special film Crossing 30,000 Miles, AI art and design.

The exhibition brings together food culture from around the world. Around the life philosophy of "eating according to the season," a number of well-known brands are jointly presenting a feast of art and life that is within reach.

The Beauty of Life unit is dedicated to showcasing creative and fresh design works, the crystallization of cultural inheritance as well as modern design thinking.

Pianist Lang Lang releases new record

Classical favorites, musical discoveries and a pair of captivating large-scale works by Saint-Saëns make up the fantastic selection of French works on Lang Lang's latest recording. Lang Lang - Saint-Saëns, set for release by Deutsche Grammophon on 2 CDs, 2 LPs and digitally on March 1, 2024, sees the Chinese superstar join forces with his wife, pianist Gina Alice, the Gewandhausorchester Orchestra and Andris Nelsons.

At the heart of the album are the magical Carnival of the Animals, Saint-Saëns's Grand Zoological Fantasy for two pianos and orchestra, and the virtuosic Piano Concerto No. 2. Also included are a dozen works for solo piano or piano four hands - a blend of Belle Époque favorites and neglected gems by female French composers.

Lang Lang's decision to open the album with a work that has enchanted generations of young listeners and introduced millions to classical music reflects his mission to attract children to the genre. 

"Many of us remember Saint-Saëns's famous Carnival of the Animals from childhood. There are a lot of clever ideas underneath all the fun. He's making a real statement, but in a very humorous way," says the pianist. 

Internationally renowned pianist Lang Lang has sold millions of albums worldwide, topping classical charts and achieving simultaneous mainstream success. Lang Lang was announced as an honoree in the Hollywood Walk of Fame Class of 2023.

Famously sneaky particles have been caught behaving in a new way.

For the first time, scientists have detected neutrinos scattering off the nucleus of an atom. The process, predicted more than four decades ago, provides a new way to test fundamental physics. It will also help scientists to better characterize the neutrino, a misfit particle that has a tiny mass and interacts so feebly with matter that it can easily sail through the entire Earth.
The detection, reported online August 3 in Science, “has really big implications,” says physicist Janet Conrad of MIT, who was not involved with the research. It fills in a missing piece of the standard model, the theory that explains how particles behave: The model predicts that neutrinos interact with nuclei. And, says Conrad, the discovery “opens up a whole new area of measurements” to further test the standard model’s predictions.

Scientists typically spot neutrinos when they interact with a single proton or neutron. But the new study measures “coherent” scattering, in which a low-energy neutrino interacts with an entire atomic nucleus at once, ricocheting away and causing the nucleus to recoil slightly in response.

“It’s exciting to measure it for the first time,” says physicist Kate Scholberg of Duke University, spokesperson for the collaboration — named COHERENT — that made the new finding.

In the past, neutrino hunters have built enormous detectors to boost their chances of catching a glimpse of the particles — a necessity because the aloof particles interact so rarely. While still rare, coherent neutrino scattering occurs more often than previously detected types of neutrino interactions. That means detectors can be smaller and still catch enough interactions to detect the process. COHERENT’s detector, a crystal of cesium and iodine, weighs only about 15 kilograms. “It’s the first handheld neutrino detector; you can just carry it around,” says physicist Juan Collar of the University of Chicago.

Collar, Scholberg and colleagues installed their detector at the Spallation Neutron Source at Oak Ridge National Laboratory in Tennessee. The facility generates bursts of neutrons and, as a by-product, produces neutrinos at energies that COHERENT’s detector can spot. When a nucleus in the crystal recoils due to a scattering neutrino, a flash of light appears and is captured by a light sensor. The signal of the recoiling nucleus is incredibly subtle — like detecting the motion of a bowling ball when hit by a ping-pong ball — which is why the effect remained undetected until now.
The amount of scattering the researchers saw agreed with the standard model. But such tests are still in their early stages, says physicist Leo Stodolsky of the Max Planck Institute for Physics in Munich, who was not involved with the research. “We’re looking forward to more detailed studies to see if it really is accurately in agreement with the expectations.” Physicists hope to find a place where the standard model breaks down, which could reveal new secrets of the universe. More precise tests may reveal discrepancies, he says. “That would be extremely interesting.”

Measuring coherent neutrino scattering could help scientists understand the processes that occur within exploding stars, or supernovas, which emit huge numbers of neutrinos (SN: 02/18/17, p. 24). The process could be used to detect supernovas as well — if a supernova explodes nearby, scientists could spot its neutrinos scattering off nuclei in their detectors.

Similar scattering might also help scientists detect dark matter, an invisible source of mass that pervades the universe. Dark matter particles could scatter off atomic nuclei just as neutrinos do, causing a recoil. The study indicates that such recoils are detectable — good news since several dark matter experiments are currently attempting to measure recoils of nuclei (SN: 11/12/16, p. 14). But it also suggests a looming problem: As dark matter detectors become more sensitive, neutrinos bouncing off the nuclei will swamp any signs of dark matter.

Coherent neutrino scattering detectors could lead to practical applications as well: Small-scale neutrino detectors could eventually detect neutrinos produced in nuclear reactors to monitor for attempts to develop nuclear weapons, for example.

Physicist Daniel Freedman of MIT, who predicted in 1974 that neutrinos would scatter off nuclei, is pleased that his prediction has finally been confirmed. “It’s a thrill.”

The 2011 tsunami that devastated Japan’s coast cast an enormous amount of debris out to sea — way out. Japanese marine life took advantage of the new floating real estate and booked a one-way trip to America. From 2012 to 2017, at least 289 living Japanese marine species washed up on the shores of North America and Hawaii, hitching rides on fishing boats, docks, buoys, crates and other nonbiodegradable objects, a team of U.S. researchers report in the Sept. 29 Science.

Organisms that surprisingly survived the harsh 7,000-kilometer journey across the Pacific Ocean on 634 items of tsunami debris ranged from 52-centimeter-long fish (a Western Pacific yellowtail amberjack) to microscopic single-celled protists. About 65 percent of the species have never been seen in North America’s Pacific waters. If these newcomers become established, they have the potential to become invasive, disrupting native marine habitats, says study coauthor James Carlton, a marine scientist at Williams College in Mystic, Conn.
Meet some of the slimiest, strangest and potentially most invasive marine castaways that took this incredible journey:

The Northern Pacific sea star (Asterias amurensis) is among the world’s most invasive species. Though this purple and yellow sea star is normally found in shallow habitats, it can live as deep as 200 meters.

Skeleton shrimp (Caprella cristibrachium and C. mutica (shown)) grasp onto algae with their strong rear claws, earning them the nickname “praying mantis of the sea.” These lanky amphipods can grow up to about 5 centimeters long and are found in the Sea of Japan.
A white, brittle Bryozoan (Biflustra grandicella) that can grow as big as a basketball is already invasive in Australia. The tiny swimming larvae of these sea creatures, also known as moss animals, may live up to a week, long enough to settle in to a new habitat.

Most of the wooden Japanese debris items collected carried at least one of seven species of large wormlike mollusks called Japanese shipworms (Psiloteredo sp.). Some of the more monstrous shipworms found, which bore into everything from wooden pilings to docks, had grown to about 50 centimeters long.
Five Japanese barred knifejaw fish (Oplegnathus fasciatus), also known as striped beakfish, were found trapped in the stern well of a Japanese fishing boat found beached in 2013 in Washington. These black-and-white striped fish are native to the Northwest Pacific Ocean and Hawaii. The well acted as a tide pool of sorts, sustaining the fish during their two-year journey.

The wavy-shelled slipper snail (Crepidula onyx), also known as a slipper limpet, has essentially come full circle in its journey around the Pacific Ocean. Native to the U.S. West Coast, the well-traveled snail became an invasive species in Japan, and now has returned to America on Japanese debris.

Campfire legends of massive, shaggy bipeds called yetis are grounded in a less mysterious truth: bears.

Eight samples of remains such as fur, bones and teeth purportedly from mountain-dwelling yetis actually come from three different kinds of bears that live in the Himalayas, researchers report November 29 in the Proceedings of the Royal Society B. A ninth sample turned out to come from a dog.

Previous analyses of smaller fragments of “yeti” DNA yielded controversial results. The new study looks at bigger chunks of DNA, analyzing the complete mitochondrial genomes from alleged yetis and comparing them with the mitochondrial genomes of various bears, including polar bears and Tibetan brown bears.
The results also give new insight into the genetic relationships between the different bears that call the Tibetan Plateau home, which could guide efforts to protect these rare subspecies. During a period of glaciation about 660,000 years ago, Himalayan brown bears were one of the first groups to branch off and become distinct from other brown bears, the data suggest.

Tibetan brown bears, on the other hand, share a more recent common ancestor with their relatives in Eurasia and North America. They might have migrated to the area around 340,000 years ago, but were probably kept geographically isolated from Himalayan brown bears by the rugged mountain terrain.

COLLEGE PARK, Md. — Campus life typically challenges students with new opportunities for learning, discovery — and intimacy with germs. Lots of germs.

That makes dormitories and their residents an ideal natural experiment to trace the germs’ paths. “You pack a bunch of college kids into a very small environment … we’re not known as being the cleanliest of people,” says sophomore Parker Kleb at the University of Maryland in College Park. Kleb is a research assistant for an ongoing study tracking the spread of respiratory viruses through a student population. The study’s goal is to better understand how these viruses move around, in order to help keep illness at bay — all the more pressing, as the current flu season is on track to be among the worst recorded in the United States.
Called “C.A.T.C.H. the Virus,” which stands for Characterizing and Tracking College Health, the study traces the trajectory of viral infections using blood samples, nasal swabs and breath samples from ailing freshmen and their closest contacts. (Tagline: It’s snot your average research study.)

Donald Milton, an environmental and occupational health physician-scientist, heads the project. On a recent day, he described the study to a classroom of freshmen he hopes to recruit. He ticked off questions this research seeks to answer: What is it that makes people susceptible to getting sick? What makes them contagious? And how do they transmit a virus to others? “Maybe your house, your room has something to do with whether you’re at risk of getting infected,” Milton said.

He had a receptive audience: members of the College Park Scholars’ Global Public Health program. Infection control is right up their alley. “How sick do we have to be?” one student asked. It’s the culprit that matters, she’s told. The study covers acute respiratory infections due to influenza viruses, adenoviruses, coronaviruses or respiratory syncytial virus, known as RSV.

Of most interest, however, is influenza. “Flu is important to everybody,” says Milton. Influenza is thought to spread among humans three ways — touch; coughing and sneezing, which launches droplets containing virus from the lungs onto surfaces; and aerosols, smaller droplets suspended in the air that could be inhaled (SN: 6/29/13, p. 9).
How much each of these modes of transmission contributes to the spread of viruses is a point of fierce debate, Milton says. And that makes infection control difficult, especially in hospitals. “If we don’t understand how [viruses] are transmitted, it’s hard to come up with policies that are really going to work.”
Milton and his colleagues recently reported that people with the flu can shed infectious virus particles just by breathing. Of 134 fine-aerosol samples taken when patients were breathing normally, 52 contained infectious influenza virus — or 39 percent, according to the study, published online January 18 in the Proceedings of the National Academy of Sciences . Those fine-aerosol particles of respiratory tract fluid are 5 microns in diameter or less, small enough to stay suspended in the air and potentially contribute to airborne transmission of the flu, the researchers say.
“This could mean that just having good cough and sneeze etiquette — sneezing or coughing into tissues — may not be enough to limit the spread of influenza,” says virologist Andrew Pekosz at Johns Hopkins University, who was not involved with the study. “Just sitting in your office and breathing could fill the air with infectious influenza.”

The C.A.T.C.H. study aims to find out if what’s in the air is catching. In two University of Maryland dorms, carbon dioxide sensors measure how much of the air comes from people’s exhalations. In addition, laboratory tests measure how much virus sick students are shedding into the air. To get those samples, students sit in a ticket booth‒sized contraption called the Gesundheit-II and breathe into a giant cone. These data can help researchers estimate students’ airborne exposure to viruses, Milton says.

Another key dataset comes from DNA testing of the viruses infecting the students. “The virus mutates reasonably fast,” Milton says, so the more people it’s moved through, the more changes it will have. By combining this molecular chain of transmission with the social chain of transmission, the researchers will try to “establish who infected whom, and where, and how,” Milton says.

The goal is to enroll 130 students in C.A.T.C.H. It’s doubtful they’ll all get sick, but not that many students from this initial group are needed to start the ball rolling, says Jennifer German, a virologist and C.A.T.C.H. student engagement coordinator. “For every index case that has an infection we’re interested in, we’re following four additional contacts,” she says. “And then if any of those contacts becomes sick, we’ll get their contacts and so on.”

The study began in November 2017. As of the end of January, German says, researchers have collected samples from five sick students, but only one was infected with a target virus, influenza. The researchers now are following three contacts from that case.

But timing and the size of the current flu outbreak may be on the researchers’ side. Kleb, the research assistant, says that students are still waiting for this season’s flu to sweep through the dorms. “Once one person gets sick, it goes around to everyone on the floor,” he says. “I’m very interested to see what happens in the next few weeks, and how the study will hopefully benefit.”

You’d be forgiven for thinking that depression has a simple explanation.

The same mantra — that the mood disorder comes from a chemical imbalance in the brain — is repeated in doctors’ offices, medical textbooks and pharmaceutical advertisements. Those ads tell us that depression can be eased by tweaking the chemicals that are off-kilter in the brain. The only problem — and it’s a big one — is that this explanation isn’t true.

The phrase “chemical imbalance” is too vague to be true or false; it doesn’t mean much of anything when it comes to the brain and all its complexity. Serotonin, the chemical messenger often tied to depression, is not the one key thing that explains depression. The same goes for other brain chemicals.
The hard truth is that despite decades of sophisticated research, we still don’t understand what depression is. There are no clear descriptions of it, and no obvious signs of it in the brain or blood.

The reasons we’re in this position are as complex as the disease itself. Commonly used measures of depression, created decades ago, neglect some important symptoms and overemphasize others, particularly among certain groups of people. Even if depression could be measured perfectly, the disorder exists amid myriad levels of complexity, from biological confluences of minuscule molecules in the brain all the way out to the influences of the world at large. Countless combinations of genetics, personality, history and life circumstances may all conspire to create the disorder in any one person. No wonder the science is stuck.

It’s easy to see why a simple “chemical imbalance” explanation holds appeal, even if it’s false, says Awais Aftab, a psychiatrist at Case Western Reserve University in Cleveland. What causes depression is nuanced, he says — “not something that can easily be captured in a slogan or buzzword.”

So here, up front, is your fair warning: There will be no satisfying wrap-up at the end of this story. You will not come away with a scientific explanation for depression, because one does not exist. But there is a way forward for depression researchers, Aftab says. It requires grappling with nuances, complexity and imperfect data.

Those hard examinations are under way. “There’s been some really interesting and exciting scientific and philosophical work,” Aftab says. That forward motion, however slow, gives him hope and may ultimately benefit the millions of people around the world weighed down by depression.

How is depression measured?
Many people who feel depressed go into a doctor’s office and get assessed with a checklist. “Yes” to trouble sleeping, “yes” to weight loss and “yes” to a depressed mood would all yield points that get tallied into a cumulative score. A high enough score may get someone a diagnosis. The process seems straightforward. But it’s not. “Even basic issues regarding measurement of depression are actually still quite open for debate,” Aftab says.

That’s why there are dozens of methods to assess depression, including the standard description set by the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, or DSM-5. This manual is meant to standardize categories of illness.

Variety in measurement is a real problem for the field and points to the lack of understanding of the disease itself, says Eiko Fried, a clinical psychologist at Leiden University in the Netherlands. Current ways of measuring depression “leave you with a really impoverished, tiny look,” Fried says.

Scales can miss important symptoms, leaving people out. “Mental pain,” for instance, was described by patients with depression and their caregivers as an important feature of the illness, researchers reported in 2020 in Lancet Psychiatry. Yet the term doesn’t show up on standard depression measurements.

One reason for the trouble is that the experience of depression is, by its nature, deeply personal, says clinical psychologist Ioana Alina Cristea of the University of Pavia in Italy. Individual patient complaints are often the best tool for diagnosing the disorder, she says. “We can never let these elements of subjectivity go.”

In the middle of the 20th century, depression was diagnosed through subjective conversation and psychoanalysis, and considered by some to be an illness of the soul. In 1960, psychiatrist Max Hamilton attempted to course-correct toward objectivity. Working at the University of Leeds in England, he published a depression scale. Today, that scale, known by its acronyms HAM-D or HRSD, is one of the most widely used depression screening tools, often used in studies measuring depression and evaluating the promise of possible treatments.
“It’s a great scheme for a scale that was made in 1960,” Fried says. Since the HRSD was published, “we have put a man on the moon, invented the internet and created powerful computers small enough to fit in people’s pockets,” Fried and his colleagues wrote in April in Nature Reviews Psychology. Yet this 60-year-old tool remains a gold standard.

Hamilton developed his scale by observing patients who had already been diagnosed with depression. They exhibited symptoms such as weight loss and slowed speech. But those mixtures of symptoms don’t apply to everyone with depression, nor do they capture nuance in symptoms.

To spot these nuances, Fried looked at 52 depression symptoms across seven different scales for depression, including Hamilton’s scale. On average, each symptom appeared in three of the seven scales. A whopping 40 percent of the symptoms appeared in only one scale, Fried reported in 2017 in the Journal of Affective Disorders. The only specific symptom common to all seven scales? “Sad mood.”

In a study that examined depression symptoms reported by 3,703 people, Fried and Randolph Nesse, an evolutionary psychiatrist at the University of Michigan Medical School in Ann Arbor, found 1,030 unique symptom profiles. Roughly 14 percent of participants had combinations of symptoms that were not shared with anyone else, the researchers reported in 2015 in the Journal of Affective Disorders.

Before reliable thermometers, the concept of temperature was murky. How do you understand the science of hot and cold without the tools to measure it? “You don’t,” Fried says. “You make a terrible measurement, and you have a terrible theory of what it is.” Depression presents a similar challenge, he says. Without good measurements, how can you possibly diagnose depression, determine whether symptoms get better with treatments or even prevent it in the first place?

Depression differs by gender, race and culture
The story gets murkier when considering who these depression scales were made for. Symptoms differ among groups of people, making the diagnosis even less relevant for certain groups.
Behavioral researcher Leslie Adams of Johns Hopkins Bloomberg School of Public Health studies depression in Black men. “It’s clear that [depression] is negatively impacting their work lives, social lives and relationships. But they’re not being diagnosed at the same rate” as other groups, she says. For instance, white people have a lifetime risk of major depression disorder of almost 18 percent; Black people’s lifetime risk is 10.4 percent, researchers reported in 2007 in JAMA Psychiatry. This discrepancy led Adams to ask: “Could there be a problem with diagnostic tools?”

Turns out, there is. Black men with depression have several characteristics that common scales miss, such as feelings of internal conflict, not communicating with others and feeling the burdens of societal pressure, Adams and colleagues reported in 2021 in BMC Public Health. A lot of depression measurements are based on questions that don’t capture these symptoms, Adams says. “ ‘Are you very sad?’ ‘Are you crying?’ Some people do not emote in the same way,” she says. “You may be missing things.”

American Indian women living in the Southeast United States also experience symptoms that aren’t adequately caught by the scales, Adams and her team found in a separate study. These women also reported experiences that do not necessarily signal depression for them but generally do for wider populations.

On common scales, “there are some items that really do not capture the experience of depression for these groups,” Adams says. For instance, a common question asks how well someone agrees with the sentence: “I felt everything I did was an effort.” That “can mean a lot of things, and it’s not necessarily tied to depression,” Adams says. The same goes for items such as, “People dislike me.” A person of color faced with racism and marginalization might agree with that, regardless of depression, she says.

Our ways to measure depression capture only a tiny slice of the big picture. The same can be said about our understanding of what’s happening in the brain.

The flawed serotonin hypothesis
Serotonin came into the spotlight in part because of the serendipitous discovery of drugs that affected serotonin receptors, called selective serotonin re­uptake inhibitors, or SSRIs. After getting its start in the late 1960s, the “serotonin hypothesis” flourished in the late ’90s, as advertisers ran commercials that told viewers that SSRIs fixed the serotonin deficit that can accompany depression. These messages changed the way people talked and thought about depression. Having a simple biological explanation helped some people and their doctors, in part by easing the shame some people felt for not being able to snap out of it on their own. It gave doctors ways to talk with people about the mood disorder.

But it was a simplified picture. A recent review of evidence, published in July in Molecular Psychiatry, finds no consistent data supporting the idea that low serotonin causes depression. Some headlines declared that the study was a grand takedown of the serotonin hypothesis. To depression researchers, the findings weren’t a surprise. Many had already realized this simple description wasn’t helpful.

There’s plenty of data suggesting that serotonin, and other chemical messengers such as dopamine and norepinephrine, are somehow involved in depression, including a study by neuropharmacologist Gitte Moos Knudsen of the University of Copenhagen. She and colleagues recently found that 17 people who were in the midst of a depressive episode released, on average, less serotonin in certain brain areas than 20 people who weren’t depressed. The study is small, but it’s one of the first to look at serotonin release in living human brains of people with depression.

But Knudsen cautions that those results, published in October in Biological Psychiatry, don’t mean that depression is fully caused by low serotonin levels. “It’s easy to defer to simple explanations,” she says.

SSRIs essentially form a molecular blockade, stopping serotonin from being reabsorbed into nerve cells and keeping the levels high between the cells. Those high levels are thought to influence nerve cell activity in ways that help people feel better.

Because the drugs can ease symptoms in about half of people with depression, it seemed to make sense that depression was caused by problems with serotonin. But just because a treatment works by doing something doesn’t mean the disease works in the opposite way. That’s backward logic, psychiatrist Nassir Ghaemi of Tufts University School of Medicine in Boston wrote in October in a Psychology Today essay. Aspirin can ease a headache, but a headache isn’t caused by low aspirin.

“We think we have a much more nuanced picture of what depression is today,” Knudsen says. The trouble is figuring out the many details. “We need to be honest with patients, to say that we don’t know everything about this,” she says.

The brain contains seven distinct classes of receptors that sense serotonin. That’s not even accounting for sensors for other messengers such as dopamine and norepinephrine. And these receptors sit on a wide variety of nerve cells, some that send signals when they sense serotonin, some that dampen signals. And serotonin, dopamine and norepinephrine are just a few of dozens of chemicals that carry information throughout a multitude of interconnected brain circuits. This complexity is so great that it renders the phrase “chemical imbalance” meaningless.

Overly simple claims — low serotonin causes depression, or low serotonin isn’t involved — serve only to keep us stymied, Aftab says. “[It] just keeps up that unhelpful binary.”
Depression research can’t ignore the world
In the 1990s, Aftab says, depression researchers got intensely focused on the brain. “They were trying to find the broken part of the brain that causes depression.” That limited view “really hurt depression research,” Aftab says. In the last 10 years or so, “there’s a general recognition that that sort of mind-set is not going to give us the answers.”

Reducing depression to specific problems of biology in the brain didn’t work, Cristea says. “If you were a doctor 10 years ago, the dream was that the neuroscience would give us the markers. We would look at the markers and say, ‘OK. You [get] this drug. You, this kind of therapy.’ But it hasn’t happened.” Part of that, she says, is because depression is an “existentially complicated disorder” that’s tough to simplify, quantify and study in a lab.

Our friendships, our loves, our setbacks and our stress can all influence our health. Take a recent study of first-year doctors in the United States. The more these doctors worked, the higher the rate of depression, scientists reported in October in the New England Journal of Medicine. Similar trends exist for caregivers of people with dementia and health care workers who kept emergency departments open during the COVID-19 pandemic. Their high-stress experiences may have prompted depression in some way.

“Depression is linked to the state of the world — and there is no denying it,” Aftab says.
Today’s research on depression ought to be more pluralistic, Adams says. “There are so many factors at play that we can’t just rest on one solution,” she says. Research from neuroscience and genetics has helped identify brain circuits, chemical messengers, cell types, molecules and genes that all may be involved in the disorder. But researchers aren’t satisfied with that. “There is other evidence that remains unexplored,” Adams says. “With our neuro­science advances, there should be similar advances in public health and psychiatric work.”

That’s happening. For her part, Adams and colleagues have just begun a study looking at moment-to-moment stressors in the lives of Black adolescents, ages 12 to 18, as measured by cell phone questionnaires. Responses, she hopes, will yield clues about depression and risk of suicide.

Other researchers are trying to fit together all of these different ways of seeing the problem. Fried, for example, is developing new concepts of depression that acknowledge the interacting systems. You tug on one aspect of it — using an antidepressant for instance, or changing sleep patterns — and see how the rest of the system reacts.

Approaches like these recognize the complexity of the problem and aim to figure out ways to handle it. We will never have a simple explanation for depression; we are now learning that one cannot possibly exist. That may sound like cold comfort to people in depression’s grip. But seeing the challenge with clear eyes may be the thing that moves us forward.