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In June of this year, Hardeep Singh Nijjar, a prominent Sikh leader as well as a Canadian citizen, was shot dead in Canada. Canada recently accused India of being involved in the assassination and kicked out an Indian diplomat, who Foreign Affairs Minister Mélanie Joly described as the head of the Indian intelligence agency in the country. In response, India promptly announced that it had expelled a senior Canadian diplomat based in India, rejecting Canada's allegations and calling them "absurd and motivated."

In recent years, disputes between India and Canada have been centered around the Sikh community in Canada, which opposes the Modi government and advocates for Sikh rights. The Sikh community is a minority ethnic group in India with a population of just over 20 million. In Canada, which is one of the largest immigrant settlements for Sikhs worldwide, the Sikh community wields significant political, commercial and economic influence. The resurgence of the separatist Khalistan movement in recent years has become a major point of contention between India and Canada, severely impacting their bilateral relations. The ongoing tussle between the two countries has put India-Canada relations further at stake.

Observers generally believe that the lack of a meeting between Canadian Prime Minister Justin Trudeau and Indian Prime Minister Narendra Modi during the G20 summit in New Delhi is a signal of danger in the relationship between the two countries. Now, both countries are escalating mutual accusations and expelling diplomats, further exposing the vulnerability of the so-called value-based alliance system led by the US.

Western countries claim to be defenders of human rights and often criticize other nations for their human rights issues. Their praise for India's so-called "democracy" is primarily driven by geopolitical interests and the desire to include India in their anti-China alliance. Western elites are well aware of the substantial differences between India's so-called "democracy" and their own. Many individuals in the West do not support India's religious and minority policies.

Qian Feng, director of the research department at the National Strategy Institute of Tsinghua University, told the Global Times that the West, especially the US, in recent years has been waving the banner of common values of democracy and freedom, attempting to develop comprehensive cooperation with India in order to contain China. They are willing to turn a blind eye to what they think are India's human rights abuses and infringement on domestic ethnic minorities, which exposes the hypocrisy of the Western alliance with India based on their so-called common values.

Noticeably, whether Westerners genuinely consider India as a democratic country like themselves is questionable. It's just that currently India is useful to Westerners, so they take advantage of the situation, said Zhao Gancheng, a research fellow from the Shanghai Institute for International Studies.

As a key member of the Western alliance and a long-standing ally of the US, Canada has played an important role for the US in establishing a so-called rules-based international order and promoting its Indo-Pacific Strategy. However, the alliance currently being formed by the US, including India, is facing increasing embarrassment. This once again demonstrates the vulnerability of the US in building such alliances and the inappropriateness of ideological alliances in the context of the development trends of the times, neglecting the diversity of national interests. Both India and Canada have expelled senior officials from each other, and if the India-Canada relationship continues to deteriorate, the US might quickly step in to "mediate." After all, for the US, intervening in Canada's affairs is a familiar and easy task.

Failed containment.Illustration: Liu Rui/GT

With the development of molecular biology and synthetic biology, human beings have gained the capability to synthesize viruses. However, it remains difficult to synthesize new viruses in a laboratory, an expert was quoted as saying by Jiankang Shibao (Health Times) on Sunday.        

An undercover video recently went viral online, in which a top Pfizer executive claimed that the biotech firm has been considering mutating COVID-19 in order to preemptively create new vaccines, according to media reports. The authenticity of the video had not been confirmed.  

“Allegations have recently been made related to gain of function and directed evolution research at Pfizer and the company would like to set the record straight,” Pfizer said on January 27. 

There are strict ethical restrictions on the study of viruses to prevent any possible leakage and to ensure the safety of experimental research, Zhao Wei, director of the biosafety research center of the School of Public Health, Southern Medical University, told the Health Times.

In an article titled “Challenges of ethical review in the development of COVID-19 vaccines and new drugs” written by Wu Qiong and other co-authors from the Eastern Theater Command of the Chinese People's Liberation Army (PLA), it said that clinical trials around the world must be in line with the Declaration of Helsinki and approved by ethics committees, according to Health Times.

During the Ebola pandemic, the National Academies of Sciences, Engineering, and Medicine identified seven ethical requirements for experimental research including scientific and social values, respect for individuals, community participation and concern for the welfare and interests of participants, said the report.

The Democratic Progressive Party (DPP) authorities' collusion with external forces will only push Taiwan into the abyss of disaster, said a Chinese mainland Taiwan affairs official at the opening of a major cross-Straits academic seminar in Chengdu, Southwest China's Sichuan Province on Thursday, alluding to the deputy leader of Taiwan island Lai Ching-te's provocative "transit" through the US.

Hosted by Cross-Straits Relations Research Center affiliated with the Taiwan Affairs Office of the State Council and with a theme of "cross-Straits relations and national rejuvenation," the two-day seminar has attracted more than 130 scholars and think tank experts from both sides of the Taiwan Straits. The 2023 seminar marks the biggest face-to-face gathering for scholars from both sides of the Taiwan Straits after the three-year COVID-19 pandemic.
Responding to Lai's "stopover" in the US, Pan Xianzhang, vice director of both the Taiwan Work Office of the Communist Party of China Central Committee and the Taiwan Affairs Office of the State Council, said during the opening that the interests of Taiwan compatriots are damaged by each and every "stopover" in the US made by Taiwan secessionists.

The attempts by Taiwan secessionists to seek "independence" and create provocation in collusion with external forces in the name of making "stopovers" fully reveals that they are troublemakers undermining the peace and stability in the Taiwan Straits, Pan said.

Noting that at present, cross-Straits relations are faced with major choices - peace or war, prosperity or recession - Pan urged Taiwan compatriots to stand on the right side of history, uphold the 1992 Consensus, firmly oppose Taiwan secessionists and interference by external forces, and join hands with compatriots in the Chinese mainland to maintain peaceful development of cross-Straits relations and advance integrated development across the Straits.

Experts and scholars attending the seminar said that the DPP authorities' collusion with external forces to seek "Taiwan independence" and create provocation is "pushing Taiwan to the brink of war" and has seriously undermined the fundamental interests of the Chinese nation. With the 2024 Taiwan regional election looming, the two sides of Straits are standing at a crossroads.

Xie Yu, a Taiwan affairs expert at the China Institutes of Contemporary International Relations, said 2023 is the first year of the resumption of cross-Straits exchanges after the COVID-19 pandemic, and the demand for exchanges, cooperation and integration accumulated by people on both sides of Straits need to be released. However, collusion between Taiwan secessionists and external forces has strained cross-Straits ties.

"Taiwan island should not become a powder keg in Asia. It should not become an ATM for US arms dealers. It should not become a runway for Western politicians," Xie said. "The mainland's moves against secessionists and external interference are actually meant to safeguard the prospects for peace across the Taiwan Straits and the well-being of the people on both sides."

Li Peng, head of the Graduate Institute for Taiwan Studies of Xiamen University, said that the mainland has always emphasized that peaceful reunification is the first choice, and the mainland strives for the prospect of peaceful reunification with the greatest sincerity and efforts.

However, the strategic competition between the US and China has intensified, the collusion between secessionists and US has deepened, and cross-Straits exchanges have been hindered. If the DPP authorities and the US ignore the mainland's strategic patience and determination and continue to challenge its red line, the situation may go in a direction that no one is willing to go, Li said.

Liu Guoshen, head of the Collaborative Innovation Center for Peaceful Development of Cross-Straits Relation, told the Global Times on Thursday that the rapid development of the Chinese mainland has brought about a high degree of maladjustment in the US and Taiwan island, which then led to the appearance of "stress syndrome," and an "overly defensive mentality."

Over the past few years, every time the US played the Taiwan card, it gave the Chinese mainland an opportunity to leverage its power through countermeasures. The mainland is very clear where the line is, so if the US wants to play the Taiwan card constantly, the "Taiwan card" may be completely confiscated in the end, Liu said.

The Taiwan question needs to be resolved in line with the great rejuvenation of the Chinese nation, the ultimate resolution lies in the development and strength of the Chinese mainland, Liu noted.

There is absolutely no possibility of Taiwan's independence. For Taiwan island, its only way out is to find its own value and positioning during the process of the great rejuvenation of the Chinese nation, the expert said.

Taiwan independence is a dead end facing the choice between war and peace. The two sides need to deepen integration and development, which can achieve the maximum well-being of Taiwan compatriots and protect their political, economic and security interests, said Yang Yizhou, a vice chairman of the All-China Association of Taiwan Compatriots.

Curves tend to put the brakes on human runners — especially those wearing prosthetics.

When navigating curves, runners must exert centripetal force to change directions, while countering the force of gravity vertically as well. They sacrifice speed in the process, and studies suggest that, in experienced sprinters, the inside leg generates less force on a curve than the outside leg.

In general, the passive, J-shaped prosthetics worn by amputee runners prevent them from generating as much force as a human ankle, and they compensate by swinging their legs faster. Researchers at University of Colorado at Boulder’s Applied Biomechanics Lab wanted to see how the inside-outside phenomenon played out in Paralympic sprinters.
The team recorded and analyzed footage of Paralympic runners with above-the-ankle amputations and of non-amputee runners running clockwise and counterclockwise on a track. Sprinters ran 3.9 percent slower with their prosthetic on the inside compared with the outside of the curve, the team reports March 16 in the Journal of Experimental Biology. Amputee runners also dropped their stride frequency when their prosthetic limb was on on the inside of the curve, which may compound the problem of the prosthetic limb generating less force against the ground than a regular ankle.

Paralympic races always run counterclockwise, and the findings suggest that this may put left-leg amputees at a disadvantage.

Don’t blame lab mice for shortfalls in their ability to mimic human immune systems — blame their upbringing.

Mice with more experience fighting pathogens have immune system reactions more like humans’, conclude two studies published online April 20. “Dirty” mice bought from pet stores or caught in the wild have more humanlike immune systems than clean lab mice do, researchers report in Nature. And in Cell Host & Microbe, scientists find that infecting lab mice with a series of viruses and parasites alters their immune responses to be similar to those of dirty mice and humans.
In recent years, scientists have debated whether mice are adequate stand-ins for humans. Some say mice are poor substitutes, and that money should instead be spent on bolstering human studies (SN: 3/23/13, p. 10). Others look at the same data and conclude that mice do a pretty good job of representing humans (SN: 9/20/14, p. 14). Plus, many important studies could not be done with humans, so mice are a necessity.

But even mouse fans recognize there is room for improvement. “All science is an approximation of the real situation,” says immunologist Andrew Macpherson of the University Hospital of Bern, Switzerland, who relies on mice models. “I don’t think anybody doubts that the models don’t always accurately recapitulate what is happening in humans.” The new papers show where mice fall short and suggest ways to improve their ability to mimic people, he says.

Lab mice’s immune system responses “really do look different” from that of humans’, says immunologist David Masopust, coauthor of both studies. Masopust, of the University of Minnesota in Minneapolis, and colleagues wondered whether those dissimilarities are due to irreconcilable differences in the genetic makeup of mice and humans or if the environment plays a role.

His group counted immune cells in blood from adult lab mice, adult humans and human umbilical cords. Of special interest were “memory CD8+ T cells,” which cull body cells that are infected with viruses or bacteria or that have become cancerous. Lab mice and human infants have few of these memory cells, while adult humans have a plethora. That indicates that lab mice have inexperienced immune systems, much like human babies.

The finding, “is one of those things that once you know it, it’s incredibly obvious,” says E. John Wherry, an immunologist at the University of Pennsylvania. “Mice are like humans raised in a bubble.”
Masopust agrees. “They live a preposterously hygienic existence.” Even mice with severe immune deficiencies can thrive in immaculately clean labs.

Ultraclean lab mice can’t emulate the sort of history most human immune systems experience, says Tiffany Reese, a viral immunologist at the University of Texas Southwestern Medical Center in Dallas. Adults carry an average of eight to 12 chronic viruses, such as Epstein-Barr virus (the cause of mononucleosis). Worm parasites infect about 2 billion people worldwide. And by adulthood, people have usually fought off multiple colds, flus and other infections.

Masopust’s team found that the memory T cell profiles of wild and pet-store mice more closely resembled that of adult humans than lab mice’s did. Housing lab mice next to pet-store mice for a month caused their immune system to change, making the lab mice resemble the dirty mice, the researchers reported in Nature. In discrepancies between studies of lab mice and humans, “the mouse may not be at fault,” Masopust says. “It’s the way that they are cared for.”

An experienced immune system not only looks different, it also works differently from an inexperienced one, Reese and colleagues report in Cell Host & Microbe. Reese infected lab mice with two types of herpesviruses, gave them the flu and inoculated them with an intestinal parasite. She then compared how uninfected mice reacted to a yellow fever vaccine with how chronically infected mice reacted. Uninfected mice made more antibodies against the vaccine. The result might help explain why some vaccines that look promising in animal studies don’t pan out in human trials.

Controlled infections may increase understanding of how pathogens interact with each other, with friendly microbes that live in the body and with the host’s immune system, says Reese’s coauthor Herbert Virgin, a viral immunologist at Washington University School of Medicine in St. Louis.

Researchers have a bias that mice are not humans, says Virgin, “But I think that’s too simplistic a view. We shouldn’t be asking whether the mouse is a perfect model for humans, but whether we can make the mouse emulate more closely the basic nature of human physiology.”

Years ago, when I visited the Daintree Rainforest in northeastern Australia, I couldn’t help but notice the signs — several of them — warning of crocodiles. Australia is home to two species of the ferocious reptiles, freshwater and saltwater — the latter of which can be found in the Daintree River. And the signs are no joke. Croc attacks aren’t common, but a few do happen every year, and some result in deaths.

Crocodiles aren’t terrifying just because they have huge teeth and a deadly bite, though. It’s that an attack appears to come from nowhere. The animals lurk just beneath the water, with only their eyes keeping a lookout for something tasty — like one of us. Now, new research shows that, while a croc may not see as well as you or I, its eyesight is quite good and well adapted for lying in wait at the water’s surface.

Nicolas Nagloo and colleagues from the University of Western Australia in Crawley took a detailed look at eyes from three young saltwater and two young freshwater crocodiles. “Both Australian species possess a bright yellow iris, a slit pupil and a relatively large lens,” the team notes May 4 in the Journal of Experimental Biology. Such features, which were known before this study, are helpful for seeing in dim light. (The animals, though, don’t have great vision underwater.) Crocs are also equipped with a “mobile slit retina” that helps the animals control how much light reaches the eye during daylight.
Dissections and examinations of the cells of the eyes revealed that both species have three types of single cones, a type of double cone and one type of rod. This means that the animals can see colors well. But the freshwater crocs appear to be a bit more sensitive to red than their saltwater counterparts (known as “salties” in Australia); that may help the freshies see in streams and rivers where there is more red light. Both species also have a horizontal streak of high spatial acuity, which allows the reptiles to scan back and forth for prey without ever moving their heads.
That the two species have eyes that are so similar is somewhat surprising given that they are separated by some 12 million years of evolution, live in different habitats and prefer different prey, with the freshwater crocs preferring smaller animals and more fish. But both species have adopted a similar hunting style in which the animals hide just beneath the water and scan the flat environment for a suitable meal. Their eyes, this study shows, are specialized to aid in such attacks.

In 2013, nearly three times as many U.S. high school students smoked cigarettes as vaped electronic cigarettes. By 2015, the trend reversed. Nearly twice as many vaped as smoked, a new study finds. For middle school students, the preference for vaping over smoking cigarettes was even stronger (2.3-fold).

Federal researchers analyzed data from the National Youth Tobacco Survey and found that some 2.39 million U.S. high school kids vaped in 2015. Fewer high schoolers, about 1.37 million, smoked cigarettes, the researchers report in the April 15 Morbidity and Mortality Weekly Report.
Since 2011, teen use of tobacco products has fallen for all categories but two: e-cigarettes and hookahs (although even hookah use has dropped since 2014). In fact, the federal researchers conclude, the steep growth in vaping seems to be keeping overall teen tobacco use stable.
The vast majority of U.S. states have banned sales of vaping supplies to minors, according to the National Conference of State Legislatures. Yet “minors do not face any significant barrier in purchasing liquid nicotine over the Internet” to vape in e-cigs, a second new study shows.

Last summer, Dmitriy Nikitin of the University of California, Irvine and his colleagues recruited three teens to buy e-liquids from 120 different U.S. online vaping-supply vendors. Only four stores did not sell e-liquids to the 16- and 17-year-olds. “I was really blown away,” Nikitin says. His team published its findings online March 19 in Nicotine & Tobacco Research.

Some of the stores packaged their e-liquids with child-friendly bonuses: toy frogs, stickers, little green army men or candy such as SweeTarts. On May 5, the U.S. Food and Drug Administration announced sweeping new regulations for e-cigs, hookahs and other tobacco products.

When scientist George Yancopoulos speaks about his experience with the Science Talent Search, he uses words like “life-changing.” Named a finalist in the competition decades ago, he credits it with helping him launch a career in medical research. Now, Yancopoulos, chief scientific officer at Regeneron Pharmaceuticals Inc., of Tarrytown, N.Y., and his fellow STS alum Leonard Schleifer, Regeneron CEO and president, want to give back to the competition.

On May 26, Regeneron and Society for Science & the Public, which created the STS program in 1942 and publishes Science News, announced that the biotechnology company will take over as the third lead sponsor of the Science Talent Search. The competition was sponsored by Westinghouse for more than five decades; in 1998, Intel became the lead sponsor.
“We are honored to be the new sponsors of the Science Talent Search, a national treasure that highlights the critical role science plays in advancing society,” Yancopoulos said in a press release. “For me, participating in the Science Talent Search was a life-changing experience that inspired my future scientific career.”
The sponsorship will include $100 million in support over 10 years, increasing the value of the scholarships and other awards offered to winners of the competition to $3.1 million annually. Regeneron will also dedicate $30 million of the total to growing the Society’s efforts in outreach and equity, designed to encourage more young people to engage in original research as part of their explorations of science.

Regeneron, founded in 1988, developed the cholesterol-fighting drug Praulent that went on sale last year and Eylea, a treatment for the vision disease wet macular degeneration, among other products. It also has a $1.7 billion deal to develop new immunotherapies for cancer with Sanofi, the French pharmaceutical firm.

To Maya Ajmera, CEO and president of Society for Science & the Public and publisher of Science News, the expansion of the competition and related outreach efforts is particularly exciting. “Through the dedication of Regeneron not only to continue but to advance the Science Talent Search, we will be expanding the program’s reach like never before,” she said.

At the end of the last Ice Age, humans undertook an epic American road trip — trekking from a northern land bridge into interior of North America. But details about the route and timing of that trip are hotly debated.

Some researchers think that humans followed a so-called “ice-free corridor” along the eastern Rocky Mountains. Studies have suggested, though, that the corridor froze over and became impassable around 21,000 years ago. Now, a bread crumb trail of fossils showing the movement of ancient bison indicates that the corridor may have reopened a few thousand years later, researchers report in the Proceedings of the National Academy of Sciences the week of June 6.

Analyzing DNA samples from 78 bison fossils unearthed in Canada, a team led by Beth Shapiro of the University of California, Santa Cruz, found that genetically distinct northern and southern populations moved north and south along the corridor by 13,000 years ago. That means humans may have also hiked along the slopes of the Rockies at the same time.

These probably weren’t the first humans to head south. Recent archaeological evidence points to early Americans trekking as far as Chile more than 15,000 years ago. But the corridor could have served as a later route, the team argues.