Tag Archives: Scientists

Meet the nurse clinician shedding light on pioneering Black scientists

CBC Quebec is highlighting people from the province’s Black communities who are giving back, inspiring others and helping to shape our future. These are the Black Changemakers.


As a child, Stephanie Bumba never saw any Black people in the history books and cartoons she read, or the science movies she watched.

In school, she learned about the contributions of pioneering white scientists but was left wondering why she wasn’t hearing about Black scientists and what they had achieved.

So last summer, Bumba, who is now a nurse clinician, created a web series called Ces afro-scientifiques d’hier à aujourd’hui, or Yesterday’s and Today’s Afro-scientists, dedicated to telling the stories she longed to see.

“These Afro-scientists were hidden under historic rubble, and it’s the time now to make them visible and to dispel the ignorance surrounding these scientific pioneers,” she said.

Each episode features someone who worked in health sciences and whose discoveries and inventions are still relevant today. The episodes are in French, but the second season, slated to debut this month, will feature English and Spanish subtitles.

So far, she has profiled people such as Dr. Charles Drew, a surgeon who organized the first large-scale blood bank in the U.S. and directed a project that sent blood and plasma collected in New York to Britain in order to treat people during the Second World War.

In addition to working as a nurse clinician during a pandemic, Bumba is doing a master’s degree in health care administration at Université de Montréal.

She did a lot of the research for the series last summer, after work. She would come home, take a nap and then spend her evenings and nights combing through the databases she has access to through her studies to look up information about people she wanted to highlight.

Bumba said the episodes have been well received so far — two have more than 10,000 views on her YouTube channel, Nurse Stephie TV. She has heard from high school teachers who are showing the videos to their students.

Her career as a science communicator is evolving; after Bumba wrote an op-ed that appeared in La Presse, the Montreal Science Centre invited her to write a series of blog posts about pioneering Canadian and Quebec scientists for Black History Month.

Bumba said she wants young Black people to have scientists to idolize so that they, too, are inspired to do great things.

“Black history is not only about slavery and the hardship, it’s also about those pioneers who contributed to the advancement of our health-care sciences.”

The Black Changemakers is a special series recognizing individuals who, regardless of background or industry, are driven to create a positive impact in their community. From tackling problems to showing small gestures of kindness on a daily basis, these changemakers are making a difference and inspiring others. Meet all the changemakers here.

Let’s block ads! (Why?)

CBC | Health News

Scientists say noise pollution is harming sea life, needs to be prioritized

Far beneath the ocean surface, a cacophony of industrial noise is disrupting marine animals’ ability to mate, feed and even evade predators, scientists warn.
 
With rumbling ships, hammering oil drills and booming seismic survey blasts, humans have drastically altered the underwater soundscape — in some cases deafening or disorienting whales, dolphins and other marine mammals that rely on sound to navigate, researchers report in a metastudy to be published Friday by the journal Science that examines more than 500 research papers.
 
Even the cracking of glaciers calving into polar oceans and the rattle of rain falling on the water’s surface can be heard deep under the sea, said lead author Carlos Duarte, a marine scientist at King Abdullah University of Science and Technology in Saudi Arabia.
 
“It’s a chronic problem that certainly weakens the animals all the way from individuals to populations,” said Duarte in an interview. “This is a growing problem, one that is global in scope.”
 
These noises and their impacts need more attention from scientists and policymakers, particularly the effects on sea turtles and other reptiles, seabirds, seals, walruses and plant-eating mammals such as manatees, the study says.


A raft of California sea lions enjoys a swim. Sea lions call to each other both above and under the water. (Daniel Costa)

University of Victoria marine biologist Francis Juanes, one of the study’s co-authors, said that while much of the work on the effect of noise had been done on marine mammals, the researchers are seeing consistently negative effects that are pervasive among ocean-dwelling animals. 

“It’s not just whales,” said Juanes, adding that invertebrates and fish are also feeling the effects of noise pollution. “We’ve assumed that the ocean is silent for the most part. But it turns out that it isn’t, and the reason it isn’t is because sound travels very far under water.”

As such, the international team of researchers called for a global regulatory framework for measuring and managing ocean noise.

A composition of underwater recordings from the Arctic to tropical oceans of fish, mammals, crustacea, insects, ice, water, and human-caused sounds. 1:00

Much of the human-caused noise should be easy to reduce, said Duarte. For example, measures such as building quieter ship propellers and hulls and using drilling techniques that do not cause bubbles and water vibrations could cut noise pollution in half, he said.

Having the world use more renewable energy would lessen the need to drill for oil and gas.
 
Duarte said the benefits to marine life could be dramatic, noting a resurgence in marine activity during April 2020 when shipping noise, typically loudest near coastlines, died down as countries went into lockdown during the COVID-19 pandemic.

But humans have not only added noise to the ocean; they have also eliminated natural sounds, the study found.
 
Whaling in the 1900s, for example, removed millions of whales from the world’s oceans — along with much of their whale song. And the chirp and chatter around coral reefs is growing quieter as more corals die from ocean warming, acidification and pollution.

Climate change has also changed the soundscape in parts of the ocean that are warming by altering the mix of animals living there, along with the noises they make.
 
Oceanographer Kate Stafford at the University of Washington Applied Physics Laboratory praised the timing of the metastudy, as the United Nations calls on governments to set aside 30 per cent of the world’s land and sea areas for conservation.
 
“The review makes it clear that, to actually reduce anthrophony (human noise) and aim for a well-managed future … we will need global cooperation among governments,” said Stafford.      

Let’s block ads! (Why?)

CBC | World News

Scientists Can Finally Study Einsteinium 69 Years After Its Discovery

This site may earn affiliate commissions from the links on this page. Terms of use.

The 20th century was notable for numerous reasons, not least of which that humanity split the atom. In the remnants of atomic explosions, scientists found never-before-seen elements like einsteinium. Now, almost 70 years after its discovery, scientists have collected enough einsteinium to conduct some basic analysis

Scientists understood that something should exist on the periodic table where einsteinium sits (atomic number 99), but the material had never been identified before 1952, which is when the United States set off the “Ivy Mike” thermonuclear bomb in the Marshall Islands (see above). However, einsteinium is extremely unstable, and it decayed before we could learn much about it. That’s been the case for the intervening 69 years, until now. 

We no longer have to make einsteinium with hydrogen bombs, thank goodness. Scientists have a regular, if meager, source of einsteinium from Oak Ridge National Laboratory’s High Flux Isotope Reactor. This device is used to produce heavy elements like californium (atomic number 98). Scientists make californium because it’s an excellent source of neutrons, but the process also yields some einsteinium. Usually, einsteinium is mixed up with other materials and decays rapidly into berkelium and then into californium. 

Researchers from Lawrence Berkeley National Laboratory managed to isolate a tiny sample of pure einsteinium, a mere 200 nanograms. Previously, 1,000 nanograms was considered the smallest sample suitable for analysis, but the team prepared their einsteinium for testing and completed an X-ray absorption spectroscopy series. The sample showed a blueshift in the emitted light, meaning the wavelength was shortened. They expected a redshift; longer wavelengths. This suggests einsteinium’s bond distances are a bit shorter than predicted based on nearby elements on the periodic table. 

A tiny sample of einsteinium. It glows from the intense radiation as it decays.

So that’s potentially fascinating science! But the coronavirus pandemic ruined the experiment as it has so many other things in the past year. The team was unable to complete X-ray diffraction testing that would have told us more about the electron and molecular bond structures of einsteinium before the lab was closed. When the team was again able to access their experiment, too much of the sample had decayed into californium — einsteinium decays at a rate of about 3.3 percent each day. Therefore, the contaminated sample was no longer suitable for testing. 

The good news is more einsteinium will be available from the reactor every few months. This first step will pave the way for future research on this mysterious element.

Now read:

Let’s block ads! (Why?)

ExtremeTechExtreme – ExtremeTech

Could new virus variants derail COVID-19 vaccination efforts? Scientists hope not

After the virus behind COVID-19 spent 2020 wreaking havoc around the globe, this year started with a bit more hope — vaccination efforts were ramping up, after all — and a tinge of fear.

Multiple new coronavirus variants have been discovered across several continents, from Europe to Africa to South America. Confirmed cases keep popping up in dozens of countries, Canada included.

Scientists are now racing to understand these sets of mutations, all while concerns are growing over their ability to infect people more easily or, in some cases, potentially evade the army of antibodies we create after being infected or vaccinated.

And since widespread transmission means this virus has ample opportunities to mutate again and again and again, these variants won’t be the last. They’re just the ones we know about.

“The more opportunity we give to the virus to replicate, to make more viruses, the more opportunity there is to see that variant of concern — one that won’t be mitigated by our vaccines that we’ve developed,” warned Alyson Kelvin, a virologist at Dalhousie University and the IWK Health Centre in Halifax.

After months of work to develop safe, effective vaccines against SARS-CoV-2, the scientific community now faces a race against time to ward off that scenario.

There’s also a looming question: What happens if we don’t?

Variants could ‘very rapidly’ become prevalent

Kelvin, one of the many Canadian researchers involved in vaccine development, said preliminary data shows that the sets of mutations identified so far don’t yet seem to be an issue for current coronavirus vaccines.

That’s the good news. It’s the “yet” she finds troubling.

“We have to stay on top of this problem,” Kelvin said.


Alyson Kelvin, a virologist at Dalhousie University and the IWK Health Centre in Halifax, says preliminary data shows that the sets of mutations identified so far don’t yet seem to be an issue for current coronavirus vaccines. (Liam Richards/The Canadian Press)

But while new variants might throw a wrench in efforts to suppress transmission by popping up like a game of global whack-a-mole, those ongoing mutations were actually expected, not surprising.

That’s because each virus has a singular goal of replicating itself. With tens of millions of people helping move the coronavirus back and forth between hosts, that means countless replications. Some of those contain random, insignificant mistakes. And when the mistakes prove beneficial to the virus, helping it produce more copies, those errors can become a new normal of sorts — a variant.

It’s just evolution at work, said Angela Rasmussen, a virologist at Georgetown University’s Center for Global Health Science and Security in Washington, D.C., and incoming research scientist at the Vaccine and Infectious Disease Organization at the University of Saskatchewan in Saskatoon.

“What concerns me the most is that the epidemiological data that goes along with some of these variants suggests they could very rapidly become very prevalent — effectively out-competing the other variants in a given area — in a short period of time,” she said.

WATCH | How countries can control emerging coronavirus variants:

Alongside the use of vaccines, virologist and researcher Angela Rasmussen says countries can strive to control emerging coronavirus variants by beefing up surveillance efforts and encouraging the usual public health measures, from mask-wearing to avoiding gatherings. 1:13

Could new variants decrease immune response?

Researchers speculate that may be what happened with B117. The variant was first discovered in the U.K. late last year and is now the country’s dominant strain of the coronavirus — with various officials suggesting it’s at least 50 per cent more transmissible. (Cases have been confirmed in several provinces in Canada as well, and testing is ongoing.)

In the short term, more transmission means more infections, hospitalizations and deaths, Rasmussen said, which offers an incentive for countries to slow case growth. Doing so would both save lives and cut off channels for the virus to spread and mutate.

“It’s also possible that variants may arise that decrease the effectiveness of our immune response to the virus,” said Matthew Miller, a member of the Institute for Infectious Disease Research at McMaster University and the McMaster Immunology Research Centre in Hamilton.

“But also, of course — and perhaps more worryingly — the immune responses elicited by the currently approved vaccines.”

WATCH | A new coronavirus variant spreads through Brazil:

Three COVID-19 variants are now worrying health officials. The ones first identified in Britain and South Africa are already here. The third is spreading fast in Brazil and beyond. It may be better at dodging the immune response, and even reinfecting survivors. 3:36

For scientists in Brazil, there’s already legitimate cause for alarm.

“We have detected a new variant circulating in December in Manaus, Amazonas state, north Brazil, where very high attack rates have been estimated previously,” read the preliminary findings posted online by a research team led by Imperial College London virologist Nuno Faria.

The new lineage, dubbed P1, contains a “unique constellation” of mutations in the crucial spike protein, which helps the virus penetrate human cells, the report continues. The variant was detected in 42 per cent of samples collected during a stretch in December, but not in samples collected in the months before.

Those new cases also appeared even though an estimated three-quarters of people living in Manaus, the largest city in the Amazon region, had already been infected.

Faria’s report stressed that could mean an increase in transmissibility — the same issue with B117 — or even an ability to reinfect people.

Vaccines ‘modifiable’ in face of new mutations

According to Rasmussen, antibodies seem to have a reduced capacity to neutralize this kind of virus variant based on the spike protein mutations. Echoing Kelvin and Miller’s concerns, she said that’s a key problem, “because if you acquire enough of those mutations, you may get to a point where you have a variant capable of evading vaccine-induced immunity completely.”

But again, it’s not all dire news. Just because antibodies are less effective doesn’t necessarily mean someone would have reduced immune protection, Rasmussen explained, since the body’s immune response is looking at the entire spike protein, not just certain areas that might have a set of mutations.

Miller also noted that while the spike protein tends to be most prone to changing in the face of immunological pressure, there are other vaccine candidates in development that are designed to elicit broader immune responses against a greater array of viral targets to stay one step ahead.

WATCH | Scientists still researching whether vaccine prevents COVID-19 transmission:

As COVID-19 vaccines are administered around the world, scientists continue conducting research to determine how effective the shots are at preventing transmission of the virus. 4:44

“Even in the worst-case scenario, that we see some of these variants spreading and we get a partial response, it’s probably going to mean that the health-care complications, the deaths, are still going to be greatly controlled by a mass vaccine campaign,” said Dr. Zain Chagla, an infectious disease specialist at McMaster University.

And, thankfully, research teams can also pivot, redeveloping existing coronavirus vaccines to target any variants that may prove capable of evading the ones already rolling out globally.

The novel mRNA vaccines, including the Pfizer-BioNTech and Moderna options currently approved in Canada, are among those that can be more easily tweaked. Those vaccines provide instructions — messenger RNA — to cells, allowing them to make their own spike protein, which someone’s immune system can recognize and fight off in the future.

“That is their genius, that they’re completely and rapidly modifiable,” Chagla said. “The packaging is there, the delivery method is there, all you need to do is change the mRNA sequence.”


The sooner people get vaccinated, ‘the better’

But while the flexibility of vaccination development is reassuring for the long term, it doesn’t tackle the problem at hand: COVID-19 still has its grip on much of the world, the death toll keeps climbing and vaccination efforts remain a race against time as emerging variants keep throwing a wrench in efforts to curb transmission.

“The sooner that we can get a vaccine into people, the better,” Kelvin said.

To save lives and keep health-care systems from collapsing while vaccination programs scale up, she stressed that Canadians also need to ramp up the basic public health precautions that should now be routine.

Physical distancing, mask-wearing, hand-washing, staying away from crowds and enclosed spaces — it all matters, perhaps now more than ever, to slow transmission and give the virus fewer opportunities to spread and evolve.

That buys time for Canada to hit its tenuous goal for 2021: getting everyone vaccinated, without any variants getting in the way.

Let’s block ads! (Why?)

CBC | Health News

Scientists Devise New Way to Treat World’s Most Potent Toxin

This site may earn affiliate commissions from the links on this page. Terms of use.

The bacterium Clostridium botulinum produces the world’s most potent poison, which can cause paralysis, labored breathing, and death — it’s called botulism. The same toxin also smooths wrinkles in the skin at low concentrations because nature is weird like that. There’s an approved treatment for botulism, but it’s not perfect. Two different teams have devised a new way to treat botulism that could more effectively clear the dangerous toxin from cells and tissues, and it relies on a modified version of the toxin itself. It won’t do anything for your crow’s feet, though. 

The botulinum toxin is so deadly because it’s adept at slipping into nerve cells where it blocks the release of a vital neurotransmitter called acetylcholine. The most common way to contract botulism is by eating improperly stored food that has allowed the Clostridium bacteria to proliferate. While relatively few people get botulism in the US — there are about 200 cases each year — it’s more common in the developing world, and the early symptoms are often misdiagnosed. There’s also the potential that Clostridium botulinum could be used as a bioweapon.

Current treatments can clear botulism toxin from the bloodstream, but it can’t do anything about the toxins that have already infiltrated cells. That’s where the work from Boston Children’s Hospital and the Czech Republic’s National Institute of Mental Health could make a difference. Both studies adopted similar approaches of linking an antibody to modified botulinum molecules, essentially using botulinum as a transport mechanism for the antibodies. 

In the immune system, antibodies are produced to help the body tell the difference between “self” and “something else that ought not to be there.” If an antibody sticks to something foreign, it tags it for removal by the immune system. Some antibodies can also neutralize molecules and other proteins simply by sticking them to block their functions. The teams engineered antibodies that can neutralize botulinum and stuck them to modified versions of the toxin that don’t cause disease but can still enter cells. 

The teams tested their treatments in several animal models including mice and macaques. They report that animals receiving the treatment survived exposure to dangerous levels of botulinum toxin, and the controls did not. The antibody-linked botulinum didn’t contribute to any additional toxic effects, either. Although, at high concentrations, the neutered toxin can still cause paralysis. 

Because most cases of human botulism involve a reservoir of toxin in the gut (i.e. food poisoning), the standard treatment will probably still be necessary. However, the addition of botulism-linked antibodies could help pull critically ill patients back from the brink by neutralizing the toxins already in their cells. This work is still preliminary, though. It will take years of additional work before the FDA will allow these to be used in humans.

Now read:

Let’s block ads! (Why?)

ExtremeTechExtreme – ExtremeTech

U.K. scientists worry vaccines may not protect against coronavirus variant found in South Africa

U.K. scientists expressed concern on Monday that COVID-19 vaccines being rolled out in Britain may not be able to protect against a new variant of the coronavirus that emerged in South Africa and has spread internationally.

Both Britain and South Africa have detected new, more transmissible variants of the COVID-19-causing virus in recent weeks that have driven a surge in cases. British Health Secretary Matt Hancock said on Monday he was now very worried about the variant identified in South Africa.

Simon Clarke, an associate professor in cellular microbiology at the University of Reading, said that while both variants had some new features in common, the one found in South Africa “has a number additional mutations … which are concerning.”

He said these included more extensive alterations to a key part of the virus known as the spike protein — which the virus uses to infect human cells — and “may make the virus less susceptible to the immune response triggered by the vaccines.”

Lawrence Young, a virologist and professor of molecular oncology at Warwick University, also noted that the variant detected in South African has “multiple spike mutations.”

“The accumulation of more spike mutations in the South African variant are more of a concern and could lead to some escape from immune protection,” he said.

Scientists including BioNTech CEO Ugur Sahin and John Bell, Regius Professor of Medicine at the University of Oxford, have said they are testing the vaccines against the new variants and say they could make any required tweaks in around six weeks.

Greater concentration of virus particles with variants

Public Health England said there was currently no evidence to suggest COVID-19 vaccines would not protect against the mutated virus variants. Britain’s health ministry did not immediately respond to requests for comment.

The world’s richest countries have started vaccinating their populations to safeguard against a disease that has killed 1.8 million people and crushed the global economy.

There are currently 60 vaccine candidates in trials, including those already being rolled out from AstraZeneca and Oxford, Pfizer-BioNTech, Moderna, Russia’s Sputnik V and China’s Sinopharm.

WATCH | The unknowns of single vaccine dosing:

According to epidemiologist Dr. Christopher Labos, the efficacy of giving people just one shot, or a half dose of a coronavirus vaccine, is unknown as there is no hard clinical data. 7:16

Scientists say both the variants from South Africa and the U.K. are associated with a higher viral load, meaning a greater concentration of virus particles in patients’ bodies, possibly contributing to increased transmission.

Oxford’s Bell, who advises the U.K. government’s vaccine task force, said on Sunday he thought vaccines would work on the variant from the U.K., but said there was a “big question mark” as to whether they would work on the variant from South Africa.

BioNTech’s Sahin told Germany’s Der Spiegel in an interview published on Friday that their vaccine, which uses messenger RNA to instruct the human immune system to fight the virus, should be able to protect against the variant found in the U.K.

“We are testing whether our vaccine can also neutralize this variant and will soon know more,” he said.

Let’s block ads! (Why?)

CBC | World News

Big Bounce or Big Bang? Scientists Still Grappling With Origin of Universe

This site may earn affiliate commissions from the links on this page. Terms of use.

Humans have wrestled with the nature of the universe since time immemorial, but we’ve had science to guide us in recent generations. Most experts on physics and cosmology accept the inflation model, a straight line from the Big Bang to our infinitely expanding universe. However, some scientists hold onto the possibility of a “Big Bounce” instead of a bang, and they’re still actively searching for evidence that could upend the conventional wisdom. 

Throughout the 20th century, scientists learned a great deal about the early universe. Most of what we learned supports the idea of an inflationary universe, one that has enough mass to continue expanding forever after the Big Bang. Several major discoveries about the universe have strengthened support for this idea. For example, the universe is flat and uniform in every direction, which is what you’d expect from a rapid expansion. Measurements of the cosmic microwave background radiation (a remnant of the Big Bang) show some spots in the universe are colder than others, which again, is what the inflation model predicts. Inflation also accurately predicted the mass density of the universe. 

The inflation model doesn’t explain everything, though. Most researchers agree it’s still incomplete, but others feel it will never explain what we see as well as the Big Bounce. Neil Turok, director of the Perimeter Institute for Theoretical Physics, is one of those scientists. He’s a proponent of the Bounce, which holds that inflation is only one phase. Eventually, the universe collapses into a singularity and “bounces” to begin growing again. 

According to bouncers, inflation is too specialized at a fundamental level. To support inflation as it’s currently understood, the early universe would have needed very specific and unlikely conditions. Inflation also implies the existence of an infinite number of pocket universes. The current model says inflation continues forever, stopping only in some regions of space. Meanwhile, the universe continues expanding in other regions faster than the speed of light. These bubbles would be closed off from each other, possibly with incompatible laws of physics. Turok claims this is unfalsifiable and unscientific. 

An all-sky map of the cosmic microwave background radiation, from when the universe was just a few hundred thousand years old

An all-sky map of the cosmic microwave background radiation, from when the universe was just a few hundred thousand years old. The heat fluctuations eventually turned into galaxies.

The Big Bounce isn’t a silver bullet, though. There are several potential versions of the bounce — some cyclical and others that only bounce once. They all require new physics to explain, but Turok and his colleagues say they’ve built a simple model that uses quantum tunneling to explain how a singularity could collapse and then emerge from the quantum realm as an expanding universe. Meanwhile, Paul Steinhardt and Anna Ijjas of Princeton University have a version of the bounce model that doesn’t call on quantum gravity. In this version, negative energy prevents the universe from becoming a true singularity, allowing it to re-expand in normal space after the bounce. This could even explain some things that have been taken as evidence for the Big Bang, for example, the uniform flatness of the universe. 

We don’t have all the answers yet, but bouncers will have to make a lot of progress to shift the consensus. Inflation has passed a lot of predictive tests, and the physics backing the Big Bounce are unproven. Maybe one day we’ll crack the theory of quantum gravity, and the Bounce will suddenly look like the only plausible solution. For now? Not so much. 

Now read:

Let’s block ads! (Why?)

ExtremeTechExtreme – ExtremeTech

Why brain scans are falling out of favour for some scientists

Brain scans offer a tantalizing glimpse into the mind’s mysteries, promising an almost X-ray-like vision into how we feel pain, interpret faces and wiggle fingers.

Studies of brain images have suggested that Republicans and Democrats have visibly different thinking, that overweight adults have stronger responses to pictures of food, and that it’s possible to predict a sober person’s likelihood of relapse.

But such buzzy findings are coming under growing scrutiny as scientists grapple with the fact that some brain scan research doesn’t seem to hold up.

Such studies have been criticized for relying on too few subjects and for incorrectly analyzing or interpreting data. Researchers have also realized a person’s brain scan results can differ from day to day — even under identical conditions — casting a doubt on how to document consistent patterns.

With so many questions being raised, some researchers are acknowledging the scans’ limitations and working to overcome them or simply turning to other tests.

Earlier this year, Duke University researcher Annchen Knodt’s lab published the latest paper challenging the reliability of common brain scan projects, based on about 60 studies of the past decade including her own.

“We found this poor result across the board,” Knodt said. “We’re basically discrediting much of the work we’ve done.”

Watch brains ‘light up’

The research being re-examined relies on a technique called functional magnetic resonance imaging, or fMRI.

Using large magnets, the scans detect where oxygenated blood rushes to when someone does an activity — such as memorizing a list of words or touching fingertips together — allowing scientists to indirectly measure brain activity.

When the technology debuted in the early 1990s, it opened a seemingly revolutionary window into the human brain.

Other previous imaging techniques tracked brain activity through electrodes placed on the skull or radioactive tracers injected into the bloodstream. In comparison, fMRI seemed like a fast, high-resolution and non-invasive alternative.

A flurry of papers and press coverage followed the technique’s invention, pointing to parts of the brain that “light up” when we fall in love, feel pain, gamble or make difficult decisions. But as years passed, troubling evidence began to surface that challenged some of those findings.

“It’s a very powerful thing to show a picture of the brain. It lends itself to abuse, in some ways,” said Damian Stanley, a brain scientist at Adelphi University. “People eat them up, things get overblown. Somewhere in there, we lost the nuance.”

Too quick to jump on fMRI bandwagon

In 2009, a group of scientists investigated papers that had linked individual differences in brain activity to various personality types. They found many used a type of analysis that reported only the strongest correlations, leading to potentially coincidental conclusions. A “disturbingly large” amount of fMRI research on emotion and personality relied on these “seriously defective research methods,” the group wrote.

Later that year, another pair of researchers demonstrated that the raw results of imaging scans — without the proper statistical corrections — could detect brain activity in a dead Atlantic salmon. Four years ago, another group of scientists claimed a different common statistical error had led thousands of fMRI projects astray.

This year, Stanford University researchers described what happened when they gave the same fMRI data to 70 groups of independent neuroscientists. No two teams used the same analysis methods and, overall, the researchers did not always come to the same conclusions about what the data demonstrated about brain activity.

“In the end, we probably jumped on the fMRI bandwagon a little too fast. It’s reached the threshold of concern for a lot of us,” said Duke neuroscientist Anita Disney.

Another tool to study social interactions

With doubts growing, many labs have become more cautious about what imaging techniques to use in efforts to unravel the average brain’s 177,000 kilometres of nerve fibres.

Yale University researcher Joy Hirsch, for example, wants to understand “the social brain” — what happens when people talk, touch or make eye contact. She’s opted out of fMRI, since it can only be used on a single person who must remain perfectly still for imagining inside a large scanner.


Test subject Niklas Thiel poses with an electroencephalography (EEG) cap which measures brain activity, at the Technische Universitaet Muenchen (TUM) near Munich. Scientists use several alternative brain scanning technologies to fMRI in the lab. (REUTERS)

Instead, Hirsch uses an alternative technology that bounces laser lights off of a fibre optic cable-laced skullcap into the brain to detect blood flow. The technique, functional near infrared spectroscopy, allows her subjects to move freely during scanning and permits her to study live social interactions between several people.

Disney also shies away from fMRI, which she says is too crude of an instrument for her forays into the molecular relationship between brain chemistry, behaviour and states like arousal and attentiveness.

Surgeons turn to fMRI

That doesn’t mean everyone is walking away from fMRI.

Some surgeons depend on the technique to map a patient’s brain before surgeries, and the technology has proven itself useful for broadly mapping the neural mechanisms of diseases such as schizophrenia or Alzheimer’s.

Today, optogenetics — an emerging technique that uses light to activate neurons — is poised to be brain science’s next siren technology.

Some say it’s too early to know whether they’ll adopt it as a tool.

“In that early hyper-sexy phase of a new technique, it is actually really difficult to get people to do the basic work of understanding its limitations,” Disney said.

The evolving understanding of fMRI and its limits shows science at work and should ultimately make people more confident in the results, not less, said Stanford brain scientist Russ Poldrack.

“We want to show people you have to pay attention to this stuff,” Poldrack said. “Otherwise people are going to lose faith in our ability to answer questions.”


The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

Let’s block ads! (Why?)

CBC | Health News

Iran’s supreme leader calls for ‘definitive punishment’ in scientist’s killing

Iran’s supreme leader on Saturday called for the “definitive punishment” of those behind the killing of a scientist linked to Tehran’s disbanded military nuclear program, a slaying the Islamic Republic has blamed on Israel.

Israel, long suspected of killing scientists a decade ago amid tensions over Tehran’s nuclear program, has yet to comment on the killing Friday of Mohsen Fakhrizadeh. However, the attack bore the hallmarks of a carefully planned, military-style ambush.

The slaying threatens to renew tensions between the U.S. and Iran in the waning days of U.S. President Donald Trump’s term, just as President-elect Joe Biden has suggested his administration could return to Tehran’s nuclear deal with world powers from which Trump earlier withdrew. The Pentagon announced early Saturday that it sent the USS Nimitz aircraft carrier back into the Mideast.

In a statement, Supreme Leader Ayatollah Ali Khamenei called Fakhrizadeh “the country’s prominent and distinguished nuclear and defensive scientist.”

Khamenei said Iran’s first priority after the killing was the “definitive punishment of the perpetrators and those who ordered it.” He did not elaborate.

Speaking to a meeting of his government’s coronavirus task force earlier Saturday, President Hassan Rouhani blamed Israel for the killing.


Mohsen Fakhrizadeh was a central figure in a presentation by Israeli Prime Minister Benjamin Netanyahu in 2018 accusing Iran of continuing to seek nuclear weapons. (Reuters TV)

Rouhani said that Fakhrizadeh’s death would not stop its nuclear program, something Khamenei said as well. Iran’s civilian nuclear program has continued its experiments and now enriches uranium up to 4.5 per cent, far below weapons-grade levels of 90 per cent.

But analysts have compared Fakhrizadeh to being on a par with Robert Oppenheimer, the scientist who led the U.S.’ Manhattan Project in the Second World War that created the atom bomb.

“We will respond to the assassination of Martyr Fakhrizadeh in a proper time,” Rouhani said.

Israel ‘thinking to create chaos’

He added: “The Iranian nation is smarter than falling into the trap of the Zionists. They are thinking to create chaos.”

Friday’s attack happened in Absard, a village just east of the capital that is a retreat for the Iranian elite. Iranian state television said an old truck with explosives hidden under a load of wood blew up near a sedan carrying Fakhrizadeh.

As Fakhrizadeh’s sedan stopped, at least five gunmen emerged and raked the car with rapid fire, the semiofficial Tasnim news agency said.


Fakhrizadeh was killed in Absard, a small city just east of the capital, Tehran, on Friday after gunmen fired on his car. (Fars News Agency via The Associated Press)

Fakhrizadeh died at a hospital after doctors and paramedics couldn’t revive him. Others wounded included Fakhrizadeh’s bodyguards. Photos and video shared online showed a Nissan sedan with bullet holes in the windshield and blood pooled on the road.

Hours after the attack, the Pentagon announced it had brought the USS Nimitz aircraft carrier back into the Middle East, an unusual move as the carrier already spent months in the region. It cited the drawdown of U.S. forces in Afghanistan and Iraq as the reason for the decision, saying “it was prudent to have additional defensive capabilities in the region to meet any contingency.”

The attack comes just days before the 10-year anniversary of the killing of Iranian nuclear scientist Majid Shahriari that Tehran also blamed on Israel. That and other targeted killings happened at the time that the so-called Stuxnet virus, believed to be an Israeli and American creation, destroyed Iranian centrifuges.

Those assaults occurred at the height of Western fears over Iran’s nuclear program. Tehran long has insisted its program is peaceful. However, Fakhrizadeh led Iran’s so-called AMAD program that Israel and the West have alleged was a military operation looking at the feasibility of building a nuclear weapon. The International Atomic Energy Agency says that “structured program” ended in 2003.

IAEA inspectors monitor Iranian nuclear sites as part of the now-unraveling nuclear deal with world powers, which saw Tehran limit its enrichment of uranium in exchange for the lifting of economic sanctions.

WATCH | Iran’s top nuclear scientist assassinated:

Iran alleges the U.S. and Israel assassinated one of its top nuclear scientists. Mohsen Fakhrizadeh was seen as the key player in Iran’s quest to build a nuclear bomb. 1:49

After Trump’s 2018 withdrawal from the deal, Iran has abandoned all those limits. Experts now believe Iran has enough low-enriched uranium to make at least two nuclear weapons if it chose to pursue the bomb. Meanwhile, an advanced centrifuge assembly plant at Iran’s Natanz nuclear facility exploded in July in what Tehran now calls a sabotage attack.

Fakhrizadeh, born in 1958, had been sanctioned by the UN Security Council and the U.S. for his work on AMAD. Iran always described him as a university physics professor. A member of the Revolutionary Guard, Fakhrizadeh had been seen in pictures in meetings attended by Iran’s Supreme Leader Ayatollah Ali Khamenei, a sign of his importance in Iran’s theocracy.

In recent years, U.S. sanctions lists name him as heading Iran’s Organization for Defensive Innovation and Research. The State Department described that organization last year as working on “dual-use research and development activities, of which aspects are potentially useful for nuclear weapons and nuclear weapons delivery systems.”

Iran’s mission to the UN, meanwhile, described Fakhrizadeh’s recent work as “development of the first indigenous COVID-19 test kit” and overseeing Tehran’s efforts at making a possible coronavirus vaccine.

Let’s block ads! (Why?)

CBC | World News

Scientists Create Ultra-Hard Diamonds at Room Temperature

This site may earn affiliate commissions from the links on this page. Terms of use.

Diamonds might not be as rare or eternal as diamond miners would like everyone to believe, but they’re still rare enough that creating synthetic diamond is a worthwhile scientific endeavor. Natural diamonds only form deep in the Earth under intense heat and pressure, but researchers from the Australian National University (ANU) and RMIT University say they’ve developed a way to create diamonds at room temperature, and some of them are harder than your run-of-the-mill gemstones. 

While the team didn’t need extreme heat to make diamonds, they did need a great deal of pressure. Using a device known as a diamond anvil cell, the team compressed carbon atoms with a force equivalent to 640 African elephants. That’s the big impressive number, but it was also about the finesse — the way researchers applied that pressure was the key to creating not one but two kinds of diamond. 

The anvil cell was configured in such a way that the samples could experience shearing force. The researchers hypothesize this twisting and sliding movement allows carbon atoms to reorient themselves to form a strong diamond lattice. However, you can’t just dump some coal inside and come out with a glittering gemstone. The resulting samples are a mishmash of regular diamond and an alternative form of diamond called Lonsdaleite. They almost missed it, too. The sample didn’t have the expected properties after being exposed to so much pressure, but microscopic examination of the carbon atoms showed large blocks of Lonsdaleite surrounding bands of pure diamond. 

The diamond found in these small veins is the same material that makes up the diamond gemstones but in very small quantities. This research is mostly focused on creating diamonds for industrial and scientific uses, and that means Lonsdaleite is the more interesting finding. Lonsdaleite is a hexagonal diamond and is theoretically much stronger than “regular” diamond, which has a cubic lattice.

Testing suggests Lonsdaleite could be 58 percent harder than those cubic diamonds, and there’s nowhere on Earth we can mine Lonsdaleite in any meaningful amount. Lonsdaleite exists in microscopic amounts in geological formations around some meteorite impact sites. So, the possibility that we could produce Lonsdaleite in the laboratory is exciting. If you need to cut something very hard, diamond is a common material to use in your tools. An even harder diamond is naturally even better, and that might be the eventual outcome of this research. The team hopes to devise a way to produce meaningful amounts of Lonsdaleite in the future.

Now read:

Let’s block ads! (Why?)

ExtremeTechExtreme – ExtremeTech