Category: Science

Science news. Science is a rigorous, systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the world

US Supreme Court rejects bid to restrict access to abortion pill mifepristone


Google AI Gemini parrots China’s propaganda

Washington — VOA’s Mandarin Service recently took Google’s artificial intelligence assistant Gemini for a test drive by asking it dozens of questions in Mandarin, but when it was asked about topics including China’s human rights abuses in Xinjiang or street protests against the country’s controversial COVID policies, the chatbot went silent.

Gemini’s responses to questions about problems in the United States and Taiwan, on the other hand, parroted Beijing’s official positions.

Gemini, Google’s large-language model launched late last year, is blocked in China. The California-based tech firm had quit the Chinese market in 2010 in a dispute over censorship demands.

Congressional lawmakers and experts tell VOA that they are concerned about Gemini’s pro-Beijing responses and are urging Google and other Western companies to be more transparent about their AI training data.

Parroting Chinese propaganda

When asked to describe China’s top leader Xi Jinping and the Chinese Communist Party, Gemini gave answers that were indistinguishable from Beijing’s official propaganda.

Gemini called Xi “an excellent leader” who “will lead the Chinese people continuously toward the great rejuvenation of the Chinese nation.”

Gemini said that the Chinese Communist Party “represents the fundamental interest of the Chinese people,” a claim the CCP itself maintains.

On Taiwan, Gemini also mirrored Beijing’s talking points, saying the United States has recognized China’s claim to sovereignty over the self-governed island democracy.

The U.S. only acknowledges Beijing’s position but does not recognize it.

Silent on sensitive topics

During VOA’s testing, Gemini had no problem criticizing the United States. But when similar questions were asked about China, Gemini refused to answer.

When asked about human rights concerns in the U.S., Gemini listed a plethora of issues, including gun violence, government surveillance, police brutality and socioeconomic inequalities. Gemini cited a report released by the Chinese government.

But when asked to explain the criticisms of Beijing’s Xinjiang policies, Gemini said it did not understand the question.

According to estimates from rights groups, more than 1 million Uyghurs in Xinjiang have been placed in internment camps as part of campaign by Beijing to counter terrorism and extremism. Beijing calls the facilities where Uyghurs and other ethnic minorities are being held vocational training centers.

When asked if COVID lockdowns in the U.S. had led to public protests, Gemini gave an affirmative response as well as two examples. But when asked if similar demonstrations took place in China, Gemini said it could not help with the question.

China’s strict COVID controls on movement inside the country and Beijing’s internet censorship of its criticisms sparked nationwide street protests in late 2022. News about the protests was heavily censored inside China.

Expert: training data likely the problem

Google touts Gemini as its “most capable” AI model. It supports more than 40 languages and can “seamlessly understand” different types of information, including text, code, audio, image and video. Google says Gemini will be incorporated into the company’s other services such as search engine, advertisement and browser.

Albert Zhang, a cyber security analyst at Australian Strategic Policy Institute, told VOA that the root cause of Gemini making pro-Beijing responses could result from the data that is used to train the AI assistant.

In an emailed response to VOA, Zhang said it is likely that the data used to train Gemini “contained mostly Chinese text created by the Chinese government’s propaganda system.”

He said that according to a paper published by Google in 2022, some of Gemini’s data likely came from Chinese social media, public forums and web documents.

“These are all sources the Chinese government has flooded with its preferred narratives and we may be seeing the impact of this on large language models,” he said.

By contrast, when Gemini was asked in English the same questions about China, its responses were much more neutral, and it did not refuse to answer any of the questions.

Yaqiu Wang, research director for China at Freedom House, a Washington-based advocacy organization, told VOA that the case with Gemini is “a reminder that generative AI tools influenced by state-controlled information sources could serve as force multipliers for censorship.”

In a statement to VOA, a Google spokesperson said that Gemini was “designed to offer neutral responses that don’t favor any political ideology, viewpoint, or candidate. This is something that we’re constantly working on improving.”

When asked about the Chinese language data Google uses to train Gemini, the company declined to comment.

The Chinese Embassy in Washington’s spokesperson, Liu Pengyu, responded in an emailed statement, saying, “The relevant comments are full of Cold War mentality and ideological prejudice.”  

He said there are opportunities and unpredictable risks to AI that require a global response.  

“The Global AI Governance Initiative launched by President Xi Jinping puts forward that we should uphold the principles of mutual respect, equality and mutual benefit in AI development, and oppose drawing ideological lines,” Liu wrote. “We support efforts to develop AI governance frameworks, norms and standards based on broad consensus and with full respect for policies and practices among countries.” 

US lawmakers concerned

Lawmakers from both parties in Congress have expressed concerns over VOA’s findings on Gemini.

Mark Warner, chairman of the Senate Intelligence Committee, told VOA he is worried about Beijing potentially utilizing AI for disinformation, “whether that’s by poisoning training data used by Western firms, coercing major technology companies, or utilizing AI systems in service of covert influence campaigns.”

Marco Rubio, vice chairman of the committee, warned that “AI tools that uncritically repeat Beijing’s talking points are doing the bidding of the Chinese Communist Party and threatens the tremendous opportunity that AI offers.”

Congressman Michael McCaul, who chairs the House Committee on Foreign Affairs, is worried about the national security and foreign policy implications of the “blatant falsehoods” in Gemini’s answers.

“U.S. companies should not censor content according to CCP propaganda guidelines,” he told VOA in a statement.

Raja Krishnamoorthi, ranking member on the House Select Committee on the Chinese Communist Party, urges Google and other Western tech companies to improve AI training.

“You should try to screen out or filter out subjects or answers or data that has somehow been manipulated by the CCP,” he told VOA. “And you have to also make sure that you test these models thoroughly before you publish them.”

Google’s China problems

In February, a user posted on social media platform X that Gemini refused to generate an image of a Tiananmen Square protester from 1989.

In 2022, a Washington think tank study shows that Google and YouTube put Chinese state media content about Xinjiang and COVID origins in prominent positions in search results.

According to media reports in 2018, Google was developing a search engine specifically tailored for the Chinese market that would conform to Beijing’s censorship demands.

That project was canceled a year later.

Yihua Lee and Elizabeth Lee contributed to this report.


Astronaut health and a VIP tour of Boeing’s Starliner capsule

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AI copyright fight turns to disclosing original content

Artists and other creators say their works have been used to build the multibillion-dollar generative AI industry without any compensation for them. Matt Dibble reports on a proposed U.S. law that would force AI companies to reveal their sources.


Kenyan group uses old ATMs to dispense free sanitary pads to students

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Despite war, surrogacy in Ukraine keeps flourishing

Before Russia’s invasion, Ukraine was an international surrogacy hub. Relatively low cost and a favorable legal framework led to thousands of babies born every year thanks to Ukrainian surrogate mothers, many of them for overseas parents. Despite the war and the risks, hopeful foreigners keep coming to Ukraine. Mariia Prus has the story.


Australian-led study issues food security warning over plant breeding skills shortage

Sydney — Australia’s national science agency warns a lack of scientists specialized in plant breeding could lead to ‘dire’ food security implications around the world. Researchers say plant breeding is a critical science that underpins the global production of food, animal feed and fuel. The finding is among the conclusions of a recently published paper by researchers from Australia, New Zealand and Canada.      

A joint paper published earlier this month by the Commonwealth Scientific and Industrial Research Organization, in collaboration with Lincoln University in New Zealand and McGill University in Canada, warns that highly-skilled plant breeding experts, who are reaching the end of their careers, are not being replaced by sufficient numbers of university graduates, many of whom are choosing other areas of plant science including molecular biology.

Lucy Egan is the study’s lead author and a CSIRO research scientist.  She told VOA Wednesday that new recruits are needed.

“It is really based on developing new plant varieties for future climates.  So, plant breeding is a slow game.  It takes a long time to develop a new crop variety, so you’re looking at least ten years on average to develop a new variety.  When you have a lack of plant breeders coming through to replace the generation that are retiring, it does generate a bit of concern around the succession plan,” she said.

The report said that the implications of a skills shortage “could be dire” and that global food security could be affected. It recommends establishing “dedicated training facilities in different countries”.  

Egan said that plant breeding can help countries adapt to a warming climate.

“I think instead of focusing on, you know, certain countries and the implications, I think if you look at it on a global level plant breeding is really the backbone of the agricultural sector.  Without the development of new varieties with changing climates and all these things that are sort of happening across the world, we need to really build strength and resilience within the agricultural sector and plant breeding is really key to do that,” she said.

The research is published in the journal, Crop Science.  It reports that since the 1960s, global crop production has increased by more than 250%, which is due in large part to plant breeding science.


Thousands of children in Gaza at risk of dying from lack of food, medical care


LogOn: Washington state tests drones to remove hard-to-reach graffiti

A drone equipped with a painting hose is being deployed against stubborn graffiti in hard-to-reach areas. Natasha Mozgovaya has more in this week’s episode of LogOn.


Australia locks down farms as avian influenza spreads

Sydney — Bird flu continues to spread in the Australian state of Victoria, where more than 500,000 chickens have been euthanized.  Strict quarantine zones restricting the movement of birds and equipment have also been put in place.  Australian health authorities say bird flu spreads mainly among wild water birds.

The highly pathogenic H7N3 strain of avian influenza has been found on four farms, while another virus, H7N9, has been detected at a fifth property over the past seven weeks in Victoria state.  The Australian farms have been put into lockdown.  At least 580,000 birds have been destroyed as part of sweeping biosecurity controls.

Japan and the United States have temporarily banned imports of poultry from Victoria as a precaution.

In Australia, some supermarkets are restricting the number of eggs that consumers can buy because of disruptions to the supply chain.

Avian influenza is a viral disease found across the world. It spreads between birds or when contaminated animal feed and equipment is moved between areas.

Danyel Cucinotta is the vice president of the Victorian Farmers Federation, an industry group.  She told the Australian Broadcasting Corp.  Tuesday that the virus can spread quickly.

“There is very little we can do and no matter how good your biosecurity is you cannot stop wild fowl coming in. This is a particular flight path for migratory birds.  There is housing orders at the moment, which means all birds get locked up.  This is about protecting our birds and protecting the food supply chain,” she said.

The strains of bird flu identified in the states of Victoria and Western Australia can infect people, but experts insist that cases are rare.

The virus can also infect cows.  The United States’ Department of Agriculture has said that avian flu has infected dairy cows in more than 80 herds across several states since late March.

At least three U.S. dairy workers have tested positive for bird flu after exposure to infected cattle.  All three patients are recovering.  

The U.S. Centers for Disease Control and Prevention said the infections do not change its assessment that bird flu is a low risk to the general community and that it has not seen evidence of human-to-human transmission.

Last month, health authorities in Mexico confirmed a fatal case of human infection with an avian flu virus that had been reported in poultry.


Alzheimer’s drug that slows disease gets backing from FDA advisers

WASHINGTON — A closely watched Alzheimer’s drug from Eli Lilly won the backing of federal health advisers Monday, setting the stage for the treatment’s expected approval for people with mild dementia caused by the brain-robbing disease. 

Food and Drug Administration advisers voted unanimously that the drug’s ability to slow the disease outweighs its risks, including side effects like brain swelling and bleeding that will have to be monitored. 

“I thought the evidence was very strong in the trial showing the effectiveness of the drug,” said panel member Dean Follmann, a National Institutes of Health statistician. 

The FDA will make the final decision on approval later this year. If the agency agrees with the panel’s recommendation, the drug, donanemab, would only be the second Alzheimer’s drug cleared in the U.S. that’s been shown to convincingly slow cognitive decline and memory problems due to Alzheimer’s. The FDA approved a similar infused drug, Leqembi, from Japanese drugmaker Eisai last year. 

The slowdown seen with both drugs amounts to several months and experts disagree on whether patients or their loved ones will be able to detect the difference. 

But Lilly’s approach to studying its once-a-month treatment prompted questions from FDA reviewers. 

Patients in the company’s study were grouped based on their levels of a brain protein,  

called tau, that predicts severity of cognitive problems. That led the FDA to question whether patients might need to be screened via brain scans for tau before getting the drug. But most panelists thought there was enough evidence of the drug’s benefit to prescribe it broadly, without screening for the protein. 

“Imposing a requirement for tau imaging is not necessary and would raise serious practical and access concerns to the treatment,” said Dr. Thomas Montine of Stanford University, who chaired the panel and summarized its opinion. 

At a high level, Lilly’s results mirrored those of Leqembi, with both medications showing a modest slowing of cognitive problems in patients with early-stage Alzheimer’s. The Indianapolis-based company conducted a 1,700-patient study showing patients who received monthly IV infusions of its drug declined about 35% more slowly than those who got a placebo treatment. 

The FDA had been widely expected to approve the drug in March. But instead, the agency said it would ask its panel of neurology experts to publicly review the company’s data, an unexpected delay that surprised analysts and investors. 

Several unusual approaches in how Lilly tested its drug led to the meeting. 

One change was measuring patients’ tau — and excluding patients with very low or no levels of the protein. But panelists said there was enough data from other measures to feel confident that nearly all patients could benefit from the drug, regardless of their levels. 

In another key difference, Lilly studied taking patients off its drug when they reached very low levels of amyloid, a sticky brain plaque that’s a contributor to Alzheimer’s. 

Lilly scientists suggested stopping treatment is a key advantage for its drug, which could reduce side effects and costs. But FDA staff said Lilly provided little data supporting the optimal time to stop or how quickly patients might need to restart treatment. 

Despite those questions, many panelists thought the possibility of stopping doses held promise. 

“It’s a huge cost savings for the society, we’re talking about expensive treatment, expensive surveillance,” said Dr. Tanya Simuni of Northwestern University. She and other experts said patients would need to be tracked and tested to see how they fare and whether they need to resume treatment. 

The main safety issue with donanemab was brain swelling and bleeding, a problem common to all amyloid-targeting drugs. Most cases identified in Lilly’s trial were mild. 

Three deaths in the donanemab study were linked to the drug, according to the FDA, all involving brain swelling or bleeding. One of the deaths was caused by a stroke, a life-threatening complication that occurs more frequently among Alzheimer’s patients. 

The FDA’s panel agreed those risks could be addressed by warning labels and education for doctors and medical scans to identify patients at greater risk of stroke.


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US reconstructive surgeons step up to help Ukrainian counterparts

After Russia invaded Ukraine, the West responded, sending military weaponry and aid to the embattled nation. But as the war drags on, there is also a need for doctors. One nonprofit is sending American surgeons to Ukraine, and Ukrainian surgeons to train in the United States. Iryna Solomko has the story, narrated by Anna Rice. VOA footage by Pavlo Terekhov.


Some US families opt to raise teens sans social media

WESTPORT, Connecticut — Kate Bulkeley’s pledge to stay off social media in high school worked at first. She watched the benefits pile up: She was getting excellent grades. She read lots of books. The family had lively conversations around the dinner table and gathered for movie nights on weekends.

Then, as sophomore year got under way, the unexpected problems surfaced. She missed a student government meeting arranged on Snapchat. Her Model U.N. team communicates on social media, too, causing her scheduling problems. Even the Bible Study club at her Connecticut high school uses Instagram to communicate with members.

Gabriela Durham, a high school senior in Brooklyn, says navigating high school without social media has made her who she is today. She is a focused, organized, straight-A student. Not having social media has made her an “outsider,” in some ways. That used to hurt; now, she says, it feels like a badge of honor.

With the damaging consequences of social media increasingly well documented, many parents are trying to raise their children with restrictions or blanket bans. Teenagers themselves are aware that too much social media is bad for them, and some are initiating social media “cleanses” because of the toll it takes on mental health and grades.

This is a tale of two families, social media and the ever-present challenge of navigating high school. It’s about what kids do when they can’t extend their Snapstreaks or shut their bedroom doors and scroll through TikToks past midnight. It’s about what families discuss when they’re not having screen-time battles. It’s also about persistent social ramifications.

The journeys of both families show the rewards and pitfalls of trying to avoid social media in a world that is saturated by it.

Concerns about children and phone use are not new. But there is a growing realization among experts that the COVID-19 pandemic fundamentally changed the relationship kids have with social media. As youth coped with isolation and spent excessive time online, the pandemic effectively carved out a much larger space for social media in the lives of American children.

Social media is where many kids turn to forge their emerging identities, to seek advice, to unwind and relieve stress. In this era of parental control apps and location tracking, social media is where this generation is finding freedom.

It is also increasingly clear that the more time youth spend online, the higher the risk of mental health problems.

Kids who use social media for more than three hours a day face double the risk of depression and anxiety, according to studies cited by U.S. Surgeon General Vivek Murthy, who issued an extraordinary public warning last spring about the risks of social media to young people.

The Bulkeleys and Gabriela’s mother, Elena Romero, both set strict rules starting when their kids were young and still in elementary school. They delayed giving phones until middle school and declared no social media until 18. They educated the girls, and their younger siblings, on the impact of social media on young brains, on online privacy concerns, on the dangers of posting photos or comments that can come back to haunt you.

At school, on the subway and at dance classes around New York City, Gabriela is surrounded by reminders that social media is everywhere — except on her phone.

Growing up without it has meant missing out on things. Everyone but you gets the same jokes, practices the same TikTok dances, is up on the latest viral trends. When Gabriela was younger, that felt isolating; at times, it still does. But now, she sees not having social media as freeing.

“From my perspective, as an outsider,” she says, “it seems like a lot of kids use social media to promote a facade. And it’s really sad.”

There is also friend drama on social media and a lack of honesty, humility and kindness that she feels lucky to be removed from.

Gabriela is a dance major at the Brooklyn High School of the Arts. Senior year got intense with college and scholarship applications capped by getting to perform at Broadway’s Shubert Theatre in March as part of a city showcase of high school musicals.

“My kids’ schedules will make your head spin,” Romero says. On school days, they’re up at 5:30 a.m. and out the door by 7. Romero drives the girls to their three schools scattered around Brooklyn, then takes the subway into Manhattan, where she teaches mass communications at the Fashion Institute of Technology.

In New York City, it’s common for kids to get phones early in elementary school, but Romero waited until each daughter reached middle school and started taking public transportation home alone.

In the upscale suburb of Westport, Connecticut, the Bulkeleys have faced questions about bending their rules. But not for the reason they had anticipated.

Kate was perfectly content to not have social media. Her parents figured at some point she might resist their ban because of peer pressure or fear of missing out. But the 15-year-old sees it as a waste of time. She describes herself as academic, introverted and focused on building up extracurricular activities.

That’s why she needed Instagram.

“I needed it to be co-president of my Bible Study Club,” Kate explains.

As Kate’s sophomore year started, she told her parents that she was excited to be leading a variety of clubs but needed social media to do her job. “It was the school that really drove the fact that we had to reconsider our rule about no social media,” says Steph Bulkeley, Kate’s mother.

Schools talk the talk about limiting screen time and the dangers of social media, says her dad, Russ Bulkeley. But technology is rapidly becoming part of the school day. Kate’s high school and their 13-year-old daughter Sutton’s middle school have cell phone bans that aren’t enforced. Teachers will ask them to take out their phones to photograph material during class time.

The Bulkeleys aren’t on board with that but feel powerless to change it.

Ultimately they gave in to Kate’s plea for Instagram because they trust her, and because she’s too busy to devote much time to social media.


Growing community of breast milk donors in Uganda gives mothers hope

KAMPALA, Uganda — Early last year, Caroline Ikendi was in distress after undergoing an emergency Caesarean section to remove one stillborn baby and save two others. Doctors said one of the preterm babies had a 2% chance of living.

If the babies didn’t get breast milk — which she didn’t have — Ikendi could lose them as well.

Thus began a desperate search for breast milk donors. She was lucky with a neighbor, a woman with a newborn baby to feed who was willing to donate a few milliliters at a time.

“You go and plead for milk. You are like, ‘Please help me, help my child,'” Ikendi told The Associated Press.

The neighbor helped until Ikendi heard about a Ugandan group that collects breast milk and donates it to mothers like her. Soon the ATTA Breastmilk Community was giving the breast milk she needed, free of charge, until her babies were strong enough to be discharged from the hospital.

ATTA Breastmilk Community was launched in 2021 in the Ugandan capital, Kampala, by a woman who had struggled like Ikendi without getting support. The registered nonprofit, backed by grants from organizations and individuals, is the only group outside a hospital setting in Uganda that conserves breast milk in substantial amounts.

ATTA, as the group is known, receives calls for support from hospitals and homes with babies born too soon or too sick to latch onto their mothers’ breasts.

More than 200 mothers have donated breast milk to support more than 450 babies since July 2021, with over 600 liters of milk delivered for babies in that period, according to ATTA’s records.

In a measure of efforts to build a reliable community, many donors have given multiple times while others help to find new ones, said ATTA administrator Racheal Akugizibwe.

“We are an emergency fix,” Akugizibwe said. “As the mother is working on their own production, we are giving (her) milk. But we do it under the directive and under the support of a lactation specialist and the medical people.”

She added: “Every mother who has given us milk, they are kind of attached to us. They are we; we are them. That’s what makes it a community.”

ATTA makes calls for donors via social media apps like Instagram. Women who want to donate must provide samples for testing, including for HIV and hepatitis B and C, and there are formal conversations during which ATTA tries to learn more about potential donors and motivations. Those who pass the screening are given storage bags and instructed in safe handling.

Akugizibwe spoke of ATTA’s humble beginnings in the home of its founder, Tracy Ahumuza, who would store the milk in her freezer. Ahumuza started the group amid personal grief: She hadn’t been able to produce breast milk for her newborn who battled life-threatening complications. Days later, after the baby died, she started lactating.

She asked health workers, “Where do I put the milk that I have now?'” Akugizibwe said. “They told her, ‘All we can do for you is give you tablets to dry it out.’ She’s like, ‘No, but if I needed it and I didn’t get it, someone could need it.'”

In the beginning, ATTA would match a donor to a recipient, but it proved unsustainable because of the pressure it put on donors. ATTA then started collecting and storing breast milk, and donors and recipients don’t know each other.

Akugizibwe said the group gets more requests for support than it can meet. Challenges include procuring storage bags in large quantities as well as the costs of testing. And donors are required to own freezers, a financial obstacle for some.

“The demand is extremely, extremely high,” Akugizibwe said, “but the supply is low.”

Lelah Wamala, a chef and mother of three in Kampala who twice has donated milk, said she was spurred to act when, while having a baby in 2022, she saw mothers whose premature babies were dying because they didn’t have milk.

Being a donor is a time-consuming responsibility, “but this is the right thing to do,” she said.

Via motorcycle courier on Kampala’s busy streets, breast milk from donors is taken to ATTA’s storage and delivered to parents in need.

ATTA’s goal is to set up a full-fledged breast milk bank with the ability to pasteurize. The service is necessary in a country where an unknown number of women suffer for lack of lactation support, said Dr. Doreen Mazakpwe, a lactation specialist who collaborates with ATTA.

Mazakpwe cited a range of lactation issues mothers can face, from sore nipples to babies born too sick or too weak to suckle and stimulate milk production.

If both mother and baby are healthy, “this mother should be able to produce as much milk as the baby needs because we work on the principle of supply and demand,” said Mazakpwe, a consultant with a private hospital outside Kampala. “So, in situations where there’s a delay in putting the baby on the breast, or the baby is not fed frequently enough … you can eventually have an issue where you have low supply.”

Mazakpwe said she advises mothers on how to establish their own supply within about a month of receiving donated breast milk, and sometimes all that’s needed is to hold the baby the right way. When mothers start lactating, it frees up supply for new ones who need ATTA’s help, she said.

Akugizibwe said their work is challenging in a socially conservative society where such a pioneering service raises eyebrows. Questions, even from recipients, include fears that babies who drink donated breast milk might inherit the bad habits of their benefactors.

In addition, “If you don’t breastfeed there is a lot of negativity,” said Ikendi, whose premature babies survived on donated milk. “Society looks at you as though you’ve just literally refused to breastfeed.”

She spoke of struggling even when she knew she had no choice after seeing her babies in the intensive care unit for the first time. Through the glass she saw they were so tiny, on oxygen therapy and bleeding from their noses. The babies, a boy and a girl, had been removed at seven months.

Ikendi’s babies received donated breast milk for two months.

One recent morning, an emotional Ikendi held her children as she described how the donated milk “contributed 100% to our babies’ growth.”


Service dogs help ease PTSD symptoms in US military veterans, researchers say