physicsworld--2020-10-21--Why knocking down Brookhaven’s iconic smokestack is a monumental mistake - Physics World

For 70 years a red-and-white striped smokestack was the first thing visitors would see when arriving at Brookhaven National Laboratory on Long Island near New York .
Painted that way to meet the requirements for navigational markers , the stack had been built for the Brookhaven Graphite Research Reactor ( BGRR ) , which fired up in 1950 .
Along with the neighbouring brown reactor building , the stack formed part of the lab ’ s first logo and was the centrepiece of Brookhaven ’ s stock photos .
Measuring about 6 m in diameter and standing almost 100 m @ @ @ @ @ @ @ object in that part of Long Island .
If you climbed the external ladder to the top , you saw water both to the north ( Long Island Sound ) and to the south ( the Atlantic Ocean ) .
The stack was designed to discharge the air that cooled the BGRR but had become slightly radioactive due to the presence of argon-41 .
This isotope has a half-life of 10.9 minutes so it decayed before reaching the ground .
Now , however , this monument to US science history is being demolished @ @ @ @ @ @ @ ’ s first major instrument but also the world ’ s first reactor built for the sole purpose of supporting basic research .
Nuclear physicists used it to develop quantitative models of the nucleus , chemists to explore the structure of matter , and biologists to study tissue and to create radioisotopes for research and treatment .
Engineers , meanwhile , came to the BGRR to study materials for submarines , ships , aircraft and spacecraft .
The BGRR was not just Brookhaven ’ s first major instrument but also the world ’ @ @ @ @ @ @ @ purpose of supporting basic research .
After the BGRR closed in 1968 , the stack served as an air-exhaust pathway for the High Flux Beam Reactor , another basic research tool .
But when that instrument was terminated in 1999 , the stack became obsolete .
Since then , apart from periodic inspections for structural integrity , it has stood there , alone and unused .
The BGRR ’ s project leader was the nuclear physicist Lyle Borst ( 1912–2002 ) , who had been research supervisor at the X-10 reactor at Oak @ @ @ @ @ @ @ served the US military during the Second World War .
Like X-10 , the BGRR consisted of a huge , air-cooled cube of graphite moderator with natural uranium fuel .
Air flowed through a gap in the centre of the cube and was sucked into the fuel channels and a series of filters before passing into air ducts that carried it to a fan building , where powerful motors blew it up the stack .
The turbulent air flow made a huge noise , and 5 m tall vertical steel panels were installed @ @ @ @ @ @ @ of the stack to dampen the sound by converting it to laminar flow .
While the stack was being built , Borst would treat visitors to a dramatic sonic shift by taking them into the stack and then to the fan house area , going from what engineers call an echoic chamber to an anechoic chamber .
Standing inside the stack was like being in a giant organ pipe , ultra-reflective of every sound .
“ You ’ d clap your hands , ” Borst told me when I spoke to him 30 @ @ @ @ @ @ @ go to the top of the stack , and bounce back own , and about 10 seconds later you ’ d hear a BANG , which was your clap.
” Sound-wise , the area near the silencers was the opposite .
“ If your partner were just a few feet away , ” Borst said , “ you couldn ’ t hear each other .
The sound was all absorbed – there was no reflection , no echo , no nothing .
It was just dead.
” Sadly , silencers have been removed @ @ @ @ @ @ @ demolition , which is scheduled to take place in early November .
John Carter , director of communications at the US Department of Energy ( DOE ) , told me that the stack is being demolished because of the “ the ongoing cost and risks of inspection , maintenance , repair , and collection and disposal of contaminated rainwater ” .
Features like the stairway I climbed would need to be periodically surveyed and fixed .
The DOE had contacted agencies involved in navigation and historical preservation , but none expressed a strong @ @ @ @ @ @ @ devoting the required resources .
We ’ ve seen many public objects toppled this year .
Throughout the US , statues of Confederate soldiers were removed , while in the UK statues of 17th-century slave traders were pulled down in both Bristol and London .
These statues are coming down because they memorialize people whom we no longer honour .
The BGRR ’ s stack is not a monument to a cause we have ceased to honour , except perhaps to those who regard reactors as objectionable .
But its removal makes me @ @ @ @ @ @ @ Galileo ’ s telescopes and James Clerk Maxwell ’ s mechanical models are preserved in museums because they were literally instrumental to key discoveries .
Other objects – like components of particle accelerators – end up in museums because the historic facilities to which they belonged are too big to preserve .
Occasionally , buildings that once housed important scientific research are saved , such as the Atomic Physics Observatory at the Carnegie Institute near Washington DC , which was built in 1938 to house a forefront Van de Graaff generator .
That @ @ @ @ @ @ @ designed to resemble an astronomical observatory so nearby residents would not be frightened by the nuclear instrument inside .
The BGRR stack is in a different category .
It is not part of the BGRR ’ s innards , but a monument by default as the last and most visible piece of the building that once contained it .
Soon , however , it will be no more .
I find that sad , because the stack is as much of a monument as Brookhaven has .
Models , images , artifacts and @ @ @ @ @ @ @ will soon be all that remain .

Physics World, where it appeared under the headline "Monumental mistake". Members of the Institute of Physics can enjoy the full issue Taken from the October 2020 issue of, where it appeared under the headline "Monumental mistake". Members of the Institute of Physics can enjoy the full issue via the Physics World app
Robert P Crease laments the disappearance of a landmark in US science history
Almost gone This iconic red-and-white stack formed part of the Brookhaven Graphite Research Reactor – the first research reactor in the world. (Courtesy: Brookhaven National Laboratory)
For 70 years a red-and-white striped smokestack was the first thing visitors would see when arriving at Brookhaven National Laboratory on Long Island near New York. Painted that way to meet the requirements for navigational markers, the stack had been built for the Brookhaven Graphite Research Reactor (BGRR), which fired up in 1950. Along with the neighbouring brown reactor building, the stack formed part of the lab’s first logo and was the centrepiece of Brookhaven’s stock photos.
Measuring about 6 m in diameter and standing almost 100 m high, the stack was the tallest object in that part of Long Island. If you climbed the external ladder to the top, you saw water both to the north (Long Island Sound) and to the south (the Atlantic Ocean). The stack was designed to discharge the air that cooled the BGRR but had become slightly radioactive due to the presence of argon-41. This isotope has a half-life of 10.9 minutes so it decayed before reaching the ground.
Now, however, this monument to US science history is being demolished.
A world first
The BGRR was not just Brookhaven’s first major instrument but also the world’s first reactor built for the sole purpose of supporting basic research. Nuclear physicists used it to develop quantitative models of the nucleus, chemists to explore the structure of matter, and biologists to study tissue and to create radioisotopes for research and treatment. Engineers, meanwhile, came to the BGRR to study materials for submarines, ships, aircraft and spacecraft.
The BGRR was not just Brookhaven’s first major instrument but also the world’s first reactor built for the sole purpose of supporting basic research.
After the BGRR closed in 1968, the stack served as an air-exhaust pathway for the High Flux Beam Reactor, another basic research tool. But when that instrument was terminated in 1999, the stack became obsolete. Since then, apart from periodic inspections for structural integrity, it has stood there, alone and unused.
The BGRR’s project leader was the nuclear physicist Lyle Borst (1912–2002), who had been research supervisor at the X-10 reactor at Oak Ridge National Laboratory in Tennessee, which served the US military during the Second World War. Like X-10, the BGRR consisted of a huge, air-cooled cube of graphite moderator with natural uranium fuel.
Air flowed through a gap in the centre of the cube and was sucked into the fuel channels and a series of filters before passing into air ducts that carried it to a fan building, where powerful motors blew it up the stack. The turbulent air flow made a huge noise, and 5 m tall vertical steel panels were installed downstream of the fan house and upstream of the stack to dampen the sound by converting it to laminar flow.
While the stack was being built, Borst would treat visitors to a dramatic sonic shift by taking them into the stack and then to the fan house area, going from what engineers call an echoic chamber to an anechoic chamber. Standing inside the stack was like being in a giant organ pipe, ultra-reflective of every sound. “You’d clap your hands,” Borst told me when I spoke to him 30 years ago, “and this would go to the top of the stack, and bounce back own, and about 10 seconds later you’d hear a BANG, which was your clap.”
Sound-wise, the area near the silencers was the opposite. “If your partner were just a few feet away,” Borst said, “you couldn’t hear each other. The sound was all absorbed – there was no reflection, no echo, no nothing. It was just dead.” Sadly, silencers have been removed in preparation for the stack’s demolition, which is scheduled to take place in early November.
John Carter, director of communications at the US Department of Energy (DOE), told me that the stack is being demolished because of the “the ongoing cost and risks of inspection, maintenance, repair, and collection and disposal of contaminated rainwater”. Features like the stairway I climbed would need to be periodically surveyed and fixed. The DOE had contacted agencies involved in navigation and historical preservation, but none expressed a strong enough interest in the stack to warrant devoting the required resources.
The critical point
We’ve seen many public objects toppled this year. Throughout the US, statues of Confederate soldiers were removed, while in the UK statues of 17th-century slave traders were pulled down in both Bristol and London. These statues are coming down because they memorialize people whom we no longer honour.
The BGRR’s stack is not a monument to a cause we have ceased to honour, but its removal makes me ponder what science historians should keep.
The BGRR’s stack is not a monument to a cause we have ceased to honour, except perhaps to those who regard reactors as objectionable. But its removal makes me ponder what science historians should keep. Galileo’s telescopes and James Clerk Maxwell’s mechanical models are preserved in museums because they were literally instrumental to key discoveries. Other objects – like components of particle accelerators – end up in museums because the historic facilities to which they belonged are too big to preserve.
Occasionally, buildings that once housed important scientific research are saved, such as the Atomic Physics Observatory at the Carnegie Institute near Washington DC, which was built in 1938 to house a forefront Van de Graaff generator. That building has some architectural interest, being designed to resemble an astronomical observatory so nearby residents would not be frightened by the nuclear instrument inside.
The BGRR stack is in a different category. It is not part of the BGRR’s innards, but a monument by default as the last and most visible piece of the building that once contained it. Soon, however, it will be no more. I find that sad, because the stack is as much of a monument as Brookhaven has. Models, images, artifacts and a time-lapse photo series of the demolition will soon be all that remain.


physicsworld--2020-10-22--Room-temperature superconductor arrives at last, a dark-matter detector mystery - Physics World

Finding a material that is a superconductor at room temperature has been the Holy Grail of condensed matter physics for @ @ @ @ @ this episode we meet Ranga Dias of the University of Rochester whose team has created @ @ @ @ @ superconductor at 15 °C .
The only catch is that it has to squeezed at @ @ @ @ @ atmospheres , and Dias explains how this pressure could be reduced .
The direct detection @ @ @ @ @ worthy of Holy Grail status , which is why particle physicists where thrilled in June @ @ @ @ @ reported a mysterious signal in their dark-matter detector .
After the announcement , theorists around @ @ @ @ @ sense of the signal – resulting in five tantalizing explanations being published in the journal @ @ @ @ @ of those papers was from an international team that includes Jayden Newstead of the University @ @ @ @ @ us to talk about what the XENON1T signal could mean .

In this podcast, Ranga Dias talks about research that is described in a paper in Nature. This paper has since been retracted by the journal.
Finding a material that is a superconductor at room temperature has been the Holy Grail of condensed matter physics for over a century. In this episode we meet Ranga Dias of the University of Rochester whose team has created a material that is a superconductor at 15 °C. The only catch is that it has to be squeezed at a pressure of two million atmospheres, and Dias explains how this pressure could be reduced.
The direct detection of dark matter is also worthy of Holy Grail status, which is why particle physicists where thrilled in June 2020 when the XENON1T collaboration reported a mysterious signal in their dark-matter detector. After the announcement, theorists around the world scrambled to make sense of the signal – resulting in five tantalizing explanations being published in the journal Physical Review Letters. One of those papers was from an international team that includes Jayden Newstead of the University of Melbourne, who joins us to talk about what the XENON1T signal could mean.


physicsworld--2020-10-22--Meteorite impacts did not magnetize the Moon’s crust, new simulations reveal - Physics World

A leading theory as to why regions of the Moon ’ s crust are magnetized has been debunked by researchers in the US , Germany , and Australia .
Through a combination of simulation techniques , a team led by Rona Oran at the Massachusetts Institute of Technology concluded that the lunar surface could not have become magnetized following high-velocity meteorite impacts in the distant past .
When the Moon ’ s surface was first studied in detail 50 years ago during the Apollo missions , researchers discovered regions of magnetization in the lunar crust that spanned hundreds of kilometres @ @ @ @ @ @ @ have not been able to provide a conclusive explanation for how these mysterious features formed – which would require the presence of a magnetic field of a strength that does not currently exist on the moon .
According to the “ core dynamo ” theory , the rotation and convection of molten metal in the core of the ancient Moon created the required magnetic field a very long time long ago .
However , many scientists have remained sceptical of this idea .
Another leading theory suggests that sections of the lunar crust @ @ @ @ @ @ @ meteorites , releasing dense clouds of plasma .
These expanding clouds would then compress and enhance the interplanetary magnetic field and amplify the induced field inside the Moon .
In their study , Oran ’ s team put the impact theory to the test using a combination of high-resolution magnetohydrodynamic simulations – which model the coupled interactions between plasmas and magnetic fields – and simulations of the vapour clouds created by the impacts responsible for large craters on the Moon ’ s surface .
By calculating the mass and thermal energy of the @ @ @ @ @ @ @ team determined the extent to which compression of the interplanetary magnetic field could have induced magnetization in the crust .
Oran and colleagues identified several factors — not previously considered – that reduce the overall enhancement of the magnetic field .
These include electrically resistive outer layers in the Moon ’ s upper mantle , which would have removed magnetic energy ; a diffusive effect that would have caused the Moon ’ s internal field to slip around its core ; and the pushing away of the compressed interplanetary magnetic field .
As @ @ @ @ @ @ @ fields produced following high-velocity impacts would have been some three orders of magnitude too weak to produce the magnetized regions that we observe today .
The team says that their study leaves the core dynamo theory as the only plausible explanation for the magnetized crust .
They also suggest that equivalent dynamo mechanisms could be responsible for magnetized crusts on Mercury , as well as many of the solar system ’ s meteor-forming asteroids .
The research is described in Science Advances .

No impact: new research suggests that meteorite collisions with the Moon did not create magnetized regions of lunar crust. (Courtesy: NASA)
A leading theory as to why regions of the Moon’s crust are magnetized has been debunked by researchers in the US, Germany, and Australia. Through a combination of simulation techniques, a team led by Rona Oran at the Massachusetts Institute of Technology concluded that the lunar surface could not have become magnetized following high-velocity meteorite impacts in the distant past.
When the Moon’s surface was first studied in detail 50 years ago during the Apollo missions, researchers discovered regions of magnetization in the lunar crust that spanned hundreds of kilometres. In the decades since, scientists have not been able to provide a conclusive explanation for how these mysterious features formed – which would require the presence of a magnetic field of a strength that does not currently exist on the Moon.
According to the “core dynamo” theory, the rotation and convection of molten metal in the core of the ancient Moon created the required magnetic field a very long time long ago. However, many scientists have remained sceptical of this idea. Another leading theory suggests that sections of the lunar crust were vapourized by the impacts of high-velocity meteorites, releasing dense clouds of plasma. These expanding clouds would then compress and enhance the interplanetary magnetic field and amplify the induced field inside the Moon.
Several simulations
In the new study, Oran’s team put the impact theory to the test using a combination of high-resolution magnetohydrodynamic simulations – which model the coupled interactions between plasmas and magnetic fields – and simulations of the vapour clouds created by the impacts responsible for large craters on the Moon’s surface. By calculating the mass and thermal energy of the vapour emitted in these events, the group determined the extent to which compression of the interplanetary magnetic field could have induced magnetization in the crust.
Oran and colleagues identified several factors – not previously considered – that reduce the overall enhancement of the magnetic field. These include electrically resistive outer layers in the Moon’s upper mantle, which would have removed magnetic energy; a diffusive effect that would have caused the Moon’s internal field to slip around its core; and the pushing away of the compressed interplanetary magnetic field. As a result, they conclude that the fields produced following high-velocity impacts would have been some three orders of magnitude too weak to produce the magnetized regions that we observe today.
The researchers say that their study leaves the core dynamo theory as the only plausible explanation for the magnetized crust. They also suggest that equivalent dynamo mechanisms could be responsible for magnetized crusts on Mercury, as well as many of the solar system’s meteor-forming asteroids.
The research is described in Science Advances.


physicsworld--2020-10-22--Molecular shapeshifter: material that gets thicker when stretched - Physics World

Most materials get thinner when stretched .
Take a rubber band , stretch it along its length , and it @ @ @ @ @ two directions , getting narrower and thinner as you pull .
But there are types @ @ @ @ @ auxetics ’ that do the opposite : getting thicker when stretched .
Human tendons , @ @ @ @ @ of metal are examples of natural auxetics , which form tiny voids when stretched , @ @ @ @ @ the material .
Recently , however , a PhD student at the University of Leeds @ @ @ @ @ new type of auxetic that displays auxetic behaviour at the molecular scale .
Watch the @ @ @ @ @ this liquid-crystal elastomer ( LCE ) could be more durable than existing auxetics , making @ @ @ @ @ , car windows and solar cells .
For a more detailed scientific description of this @ @ @ @ @ feature by Helen Gleeson , the physicist who supervised this research .

Most materials get thinner when stretched. Take a rubber band, stretch it along its length, and it will shrink in the other two directions, getting narrower and thinner as you pull. But there are types of materials known as ‘auxetics’ that do the opposite: getting thicker when stretched. Human tendons, cat skin and certain types of metal are examples of natural auxetics, which form tiny voids when stretched, lowering the overall density of the material.
Recently, however, a PhD student at the University of Leeds, UK, discovered a new type of auxetic that displays auxetic behaviour at the molecular scale. Watch the video to find out why this liquid-crystal elastomer (LCE) could be more durable than existing auxetics, making it suitable for body armour, car windows and solar cells. For a more detailed scientific description of this new material, read this feature by Helen Gleeson, the physicist who supervised this research.


physicsworld--2020-10-22--#BlackInPhysics week set to celebrate Black physicists - Physics World

What are the aims of # BlackinPhysics week ?
Charles Brown ( CB ) : # BlackInPhysics week , which runs from 25 to 31 October , is dedicated to celebrating the contributions that Black physicists make to science and to revealing a more inclusive picture of what a physicist looks like .
The aim of the week is to strengthen intra- and inter-generational connections between Black physicists , encourage long-lasting collaborations and further push for supportive environments where current and future Black physicists everywhere can thrive .
How did the idea come about ?
Xandria Quichocho ( XQ ) @ @ @ @ @ @ @ BlackInPhysics week and it has been a team effort .
The organizing team was inspired by initiatives such as Black Birders Week , # BlackinAstro and # BlackintheIvory , which gave voice to the aggressions , racism and sexism faced by Black academics across the world .
Each of these movements lit the kindling that is growing into a larger fire that is saying “ I am Black , I am a scientist and my life matters.
” We are all living in the middle of a global revolution that is shouting and @ @ @ @ @ @ @ .
As people who identify as Black , we have been told time and time again to be neutral and objective in our professional workplaces and places of study .
But as the news is saturated with the constant injustices and brutality that are happening to Black , Indigenous and people of colour , it is impossible to pretend that we can go into our classrooms , into our labs and ignore what is going in the outside world .
For us , it is not just the “ outside ” – it @ @ @ @ @ @ @ you to organize # BlackinPhysics ?
Eileen Gonzales ( EG ) : I wanted to be part of something that focused on connecting members of our community , especially helping to link students who may be the only Black physicist at their institution .
We all wanted to focus on all aspects of being Black in physics and not just our science .
We found there is a lack of these things being addressed specifically for Black physicists in our community .
It is either you focus on being Black in physics and @ @ @ @ @ @ @ on a workshop targeting , say , impostor syndrome , but it will lack the perspective of a Black person .
We wanted to provide a space for conversations like what it is like to deal with impostor syndrome , mental health and advocating for yourself – all through the lens of a Black physicist .
What are the most pressing barriers facing Black physicists ?
XQ : “ Representation , representation , representation !
” is a phrase we ’ ve all been hearing recently .
It is talked about regarding movie @ @ @ @ @ @ @ rooms and even children ’ s programming .
A lack of representation for Black , Indigenous and people of colour isn ’ t just a problem in popular media ; it is an issue that persists and exists in physics departments and labs .
According to data collected by the American Physical Society from 2006 to 2016 , only 4 % of BSc physics degrees were earned by students who self-identified as Black or African American .
Unfortunately , this number does not include students who identified as Black mixed-race , more than @ @ @ @ @ @ @ and Afro-Indigenous .
Are the barriers simply a problem with underrepresentation ?
XQ : It ’ s just the beginning of the problem .
Academia itself is a barrier to Black physicists .
Traditional STEM programmes operate under the flawed myth of the meritocracy – and completely ignore the biases , racism and sexism that Black , Indigenous and people of colour combat every day .
The structures in academia and in physics intentionally bar Black students from gaining access to the field or remaining in it once they have broken the glass @ @ @ @ @ @ @ physics PhDs were awarded in the US in 2017 alone but this year will see only the 100th Black American woman ever to achieve that feat .
However , there has been a shift in these past few months to change this .
Universities , national labs and individuals that took part in # ShutDownSTEM and the # Strike4BlackLives over the summer made the first steps towards creating a more equitable and physics field .
The American Institute of Physics recently published its extensive and detailed TEAM-UP Report that not only highlights the @ @ @ @ @ @ @ includes real , long-lasting strategies that departments can take to create a safer environment for Black students to thrive in .
What events are planned during # BlackInPhysics week ?
EG : We will run both professional and social events targeted at Black physics students , postdocs , faculty , industry and the general public .
There are panel discussions aimed at specific career stages such as dealing with impostor syndrome and mental health as well as a three-minute thesis competition for PhD students to showcase their work .
We will also host @ @ @ @ @ @ @ “ ask-a-scientist ” session for the general public to engage in conversations with Black physicists , a special Halloween Murder Mystery as well as other events to provide a place for the community to network , relax and socialize .
Each day will also feature an article by a Black physicist regarding different aspects of our identities [ published jointly on the Physics World and Physics Today websites ] .
What was the reason for splitting up the week in terms of different areas of physics ?
CB : Dedicating an entire day @ @ @ @ @ @ @ physicists within that area to learn about each other and form a community , but also to form a community with varied research interests – often a recipe for innovation and breakthrough .
Now , if someone wants to learn about the work of Black atomic physicists , they can simply search the hashtag # BlackinAMO on Twitter .
Splitting the week by area has the added benefit of helping employers identify and potentially hire for positions .
It also allows us to clearly demonstrate the excellent and wide-ranging work that Black physicists @ @ @ @ @ @ @ .
How will you know that the week has been a success or had an impact ?
CB : We will judge the success by how effective it has been to celebrate the work of Black physicists and whether it has helped to build an engaged community .
It is crucial for our success that this work is done in a way that honours Black physicists ’ rich set of identities .
Black people are not a monolith , and so neither are Black physicists .
We are men , women , non-binary @ @ @ @ @ @ @ these identities we all enrich the physics discipline .
We want to see younger Black physicists discovering their unknown peers and near-peers and we want them to interact with , and be inspired by , more senior Black physicists .
We want the senior physicists to learn about the young and talented Black physicists for whom they cleared the path .
We want Black physicists of all ranks to learn and hone important skills and tools to help them flourish .
And , importantly , we want Black physicists spanning different generations to @ @ @ @ @ @ @ at the week ’ s social events .
We also want non-scientists and non-physicists to interact with as many Black physicists as possible .
And what about the benefits to the public ?
CB : # BlackinPhysics week offers a unique opportunity for the public to engage each other in a way that is atypical , yet beneficial and empowering for all parties involved .
For example , the public will be engaged with physics content on social media and will have the ability to speak directly to , and learn from , @ @ @ @ @ @ @ Physicists will also have myriad opportunities to practise presenting their research in concise yet engaging ways to physicists and non-physicists alike .
Do you plan to keep the initiative going ?
EG : Yes , it will continue .
Part of our mission is to strengthen intergenerational connections between physicists .
We hope to encourage the connections made during # BlackInPhysics week and to build new links through our website and on Twitter with additional future events .
A longer-term goal we have is to create a database of all Black physicists that @ @ @ @ @ @ @ presentation invitations and so on .
Do you think the initiative could be mirrored in other countries ?
XQ : # BlackInPhysics is a growing international collaboration .
While the current organizing team is made of 12 individuals , our nationalities and histories span the globe .
One of the amazing things about living in this age of social media is that we can extend the invitation to this event to a global audience .
We aren ’ t using the hashtag , “ US Black physicists ” or “ Black physicists in @ @ @ @ @ @ @ BlackInPhysics is meant for the people of the African diaspora , for immigrants , for Black and African physicists across the world to connect with each other , to build these connections and communities across oceans .
# BlackInPhysics week is a part of a global movement of Black scientists coming together to say , “ We are here !
” • For more details about # BlackInPhysics week , which runs from 25 to 31 October , see www.blackinphysics.org or follow @ BlackInPhysics and # BlackInPhysics on Twitter .

Charles Brown, Eileen Gonzales and Xandria Quichocho talk to Michael Banks about the barriers facing Black physicists and how #BlackInPhysics week aims to boost their visibility
Leading the way: From left to right: Charles Brown from the University of California, Berkeley, Eileen Gonzales from the Carl Sagan Institute, Cornell University, and Xandria Quichocho from Michigan State University were part of a team of 12 who have organized #BlackInPhysics Week.
What are the aims of #BlackinPhysics week?
Charles Brown (CB): #BlackInPhysics week, which runs from 25 to 31 October, is dedicated to celebrating the contributions that Black physicists make to science and to revealing a more inclusive picture of what a physicist looks like. The aim of the week is to strengthen intra- and inter-generational connections between Black physicists, encourage long-lasting collaborations and further push for supportive environments where current and future Black physicists everywhere can thrive.
How did the idea come about?
Xandria Quichocho (XQ): There are 12 organizers of #BlackInPhysics week and it has been a team effort. The organizing team was inspired by initiatives such as Black Birders Week, #BlackinAstro and #BlackintheIvory, which gave voice to the aggressions, racism and sexism faced by Black academics across the world. Each of these movements lit the kindling that is growing into a larger fire that is saying “I am Black, I am a scientist and my life matters.” We are all living in the middle of a global revolution that is shouting and telling the world that Black Lives Matter. As people who identify as Black, we have been told time and time again to be neutral and objective in our professional workplaces and places of study. But as the news is saturated with the constant injustices and brutality that are happening to Black, Indigenous and people of colour, it is impossible to pretend that we can go into our classrooms, into our labs and ignore what is going in the outside world. For us, it is not just the “outside” – it is our everyday lives.
What inspired you to organize #BlackinPhysics?
Eileen Gonzales (EG): I wanted to be part of something that focused on connecting members of our community, especially helping to link students who may be the only Black physicist at their institution. We all wanted to focus on all aspects of being Black in physics and not just our science. We found there is a lack of these things being addressed specifically for Black physicists in our community. It is either you focus on being Black in physics and showcase the science, or you focus on a workshop targeting, say, impostor syndrome, but it will lack the perspective of a Black person. We wanted to provide a space for conversations like what it is like to deal with impostor syndrome, mental health and advocating for yourself – all through the lens of a Black physicist.
What are the most pressing barriers facing Black physicists?
XQ: “Representation, representation, representation!” is a phrase we’ve all been hearing recently. It is talked about regarding movie casting, television programmes, in board rooms and even children’s programming. A lack of representation for Black, Indigenous and people of colour isn’t just a problem in popular media; it is an issue that persists and exists in physics departments and labs. According to data collected by the American Physical Society from 2006 to 2016, only 4% of BSc physics degrees were earned by students who self-identified as Black or African American. Unfortunately, this number does not include students who identified as Black mixed-race, more than one race including Black, or Afro-Latinx and Afro-Indigenous.
Are the barriers simply a problem with underrepresentation?
XQ: It’s just the beginning of the problem. Academia itself is a barrier to Black physicists. Traditional STEM programmes operate under the flawed myth of the meritocracy – and completely ignore the biases, racism and sexism that Black, Indigenous and people of colour combat every day. The structures in academia and in physics intentionally bar Black students from gaining access to the field or remaining in it once they have broken the glass ceiling. For example, about 1800 physics PhDs were awarded in the US in 2017 alone but this year will see only the 100th Black American woman ever to achieve that feat. However, there has been a shift in these past few months to change this. Universities, national labs and individuals that took part in #ShutDownSTEM and the #Strike4BlackLives over the summer made the first steps towards creating a more equitable and physics field. The American Institute of Physics recently published its extensive and detailed TEAM-UP Report that not only highlights the barriers for Black students in physics but includes real, long-lasting strategies that departments can take to create a safer environment for Black students to thrive in.
We will judge the success by how effective it has been to celebrate the work of Black physicists and whether it has helped to build an engaged community
What events are planned during #BlackInPhysics week?
EG: We will run both professional and social events targeted at Black physics students, postdocs, faculty, industry and the general public. There are panel discussions aimed at specific career stages such as dealing with impostor syndrome and mental health as well as a three-minute thesis competition for PhD students to showcase their work. We will also host six days of social events including an “ask-a-scientist” session for the general public to engage in conversations with Black physicists, a special Halloween Murder Mystery as well as other events to provide a place for the community to network, relax and socialize. Each day will also feature an article by a Black physicist regarding different aspects of our identities [published jointly on the Physics World and Physics Today websites].
What was the reason for splitting up the week in terms of different areas of physics?
CB: Dedicating an entire day to a single area not only allows physicists within that area to learn about each other and form a community, but also to form a community with varied research interests – often a recipe for innovation and breakthrough. Now, if someone wants to learn about the work of Black atomic physicists, they can simply search the hashtag #BlackinAMO on Twitter. Splitting the week by area has the added benefit of helping employers identify and potentially hire for positions. It also allows us to clearly demonstrate the excellent and wide-ranging work that Black physicists do in their respective areas of physics.
How will you know that the week has been a success or had an impact?
CB: We will judge the success by how effective it has been to celebrate the work of Black physicists and whether it has helped to build an engaged community. It is crucial for our success that this work is done in a way that honours Black physicists’ rich set of identities. Black people are not a monolith, and so neither are Black physicists. We are men, women, non-binary, LGBTQ+, disabled, and in these identities we all enrich the physics discipline. We want to see younger Black physicists discovering their unknown peers and near-peers and we want them to interact with, and be inspired by, more senior Black physicists. We want the senior physicists to learn about the young and talented Black physicists for whom they cleared the path. We want Black physicists of all ranks to learn and hone important skills and tools to help them flourish. And, importantly, we want Black physicists spanning different generations to socialize and have fun with each other at the week’s social events. We also want non-scientists and non-physicists to interact with as many Black physicists as possible.
And what about the benefits to the public?
CB: #BlackinPhysics week offers a unique opportunity for the public to engage each other in a way that is atypical, yet beneficial and empowering for all parties involved. For example, the public will be engaged with physics content on social media and will have the ability to speak directly to, and learn from, physicists, thereby increasing scientific literacy. Physicists will also have myriad opportunities to practise presenting their research in concise yet engaging ways to physicists and non-physicists alike.
Do you plan to keep the initiative going?
EG: Yes, it will continue. Part of our mission is to strengthen intergenerational connections between physicists. We hope to encourage the connections made during #BlackInPhysics week and to build new links through our website and on Twitter with additional future events. A longer-term goal we have is to create a database of all Black physicists that can be used for job hiring, presentation invitations and so on.
Do you think the initiative could be mirrored in other countries?
XQ: #BlackInPhysics is a growing international collaboration. While the current organizing team is made of 12 individuals, our nationalities and histories span the globe. One of the amazing things about living in this age of social media is that we can extend the invitation to this event to a global audience. We aren’t using the hashtag, “US Black physicists” or “Black physicists in America” for a reason. #BlackInPhysics is meant for the people of the African diaspora, for immigrants, for Black and African physicists across the world to connect with each other, to build these connections and communities across oceans. #BlackInPhysics week is a part of a global movement of Black scientists coming together to say, “We are here!”
For more details about#BlackInPhysics week, which runs from 25 to 31 October, see www.blackinphysics.org or follow @BlackInPhysics and #BlackInPhysics on Twitter.


physicsworld--2020-10-22--Elekta offers ongoing innovation in precision radiation medicine - Physics World

From software launches to new radiation therapy equipment , Elekta continues to innovate in the field of cancer-treatment technologies .
The company has released , acquired and gained regulatory approval for a range of new radiotherapy products over the last 12 months .
In December 2019 , Elekta received 510 ( k ) pre-market notification from the US Food and Drug Administration ( FDA ) for the use of diffusion-weighted imaging ( DWI ) datasets obtained with the Elekta Unity MR-linac .
This approval expanded the clinical utility of Elekta Unity to include biologic assessment of tumour response during therapy @ @ @ @ @ @ @ just on gross anatomic changes , but also on early biologic changes at the cellular level .
DWI works by creating a map of the diffusion of water molecules at the cellular level , which can be processed to generate the apparent diffusion coefficient ( ADC ) .
A growing body of evidence shows that changes in ADC within a tumour can provide important insights into an individual ’ s tumour response .
Such insights , which were previously unavailable during radiation treatment , can support further personalization of the radiotherapy regimen by @ @ @ @ @ @ @ , DWI can improve a clinician ’ s ability to deliver the right dose to the right part of the tumour .
To learn more , check out the business line update from Lionel Hadjabjeda , president , MR-Linac solutions , on Wednesday 28 October at 12.00 p.m .
ET .
Elekta ’ s MOSAIQ Plaza* is a powerful , comprehensive set of digital tools that connects users to their colleagues , data and patients , throughout the entire patient workflow .
This fully integrated software suite helps to drive efficiencies , standardize @ @ @ @ @ @ @ For example , Elekta recently acquired and continued development of the technology behind MOSAIQ Voice , which enables users to work at the speed of their voice .
The tool allows clinical tasks in MOSAIQ to be completed via dictation , streamlining documentation and reducing workload .
Another game-changing workflow advancement is MOSAIQ SmartClinic .
With a wide range of professionals involved in cancer patient care , MOSAIQ SmartClinic provides a transparent approach to care management , connecting users to the information that they need , whenever and wherever .
To learn more @ @ @ @ @ @ @ from Andrew Wilson , president , oncology informatics solutions , on Tuesday 27 October at 12.00 p.m .
ET .
Cervical cancer screening , via Pap and HPV tests , has successfully reduced the incidence of cervical cancer via early detection .
But for women still confronted with this disease , treatments such as brachytherapy offer a proven way to improve overall survival .
In April 2000 .
Elekta introduced the Geneva brachytherapy applicator .
Designed for cervical cancer up to stage IIB , Geneva could help up to 75 % of patients @ @ @ @ @ @ @ mid-July , Geneva received FDA 510 ( k ) clearance .
With a comprehensive range of ovoid ( 13–40 mm ) and intrauterine tube ( 30–80 mm ) sizes , in addition to a new interstitial intrauterine tube to expand treatment options after hysterectomy , Geneva can accommodate most female anatomies .
Clinicians can now take advantage of a single gynaecological applicator to treat most cervical cancer patients via intracavitary and/or interstitial brachytherapy .
To learn more , check out the business line update from John Lapré , president , brachytherapy solutions , @ @ @ @ @ @ @ .
ET .
On 12 June , Elekta introduced Leksell Gamma Knife Lightning** , a treatment optimizer designed to boost Gamma Knife radiosurgery workflows and improve plan quality .
Lightning , which has been available commercially since the end of June , enables clinicians to create plans for multiple targets in less than a minute and to include beam-on time as a constraint , greatly reducing overall treatment time .
Gamma Knife Lightning addresses the challenge of increasing automation and speed in the stereotactic radiosurgery workflow , while also ensuring a personalized plan @ @ @ @ @ @ @ .
The ability to create multiple plans in less than 60 s will allow physicians to compare plans and select the best option .
And by controlling beam-on time , they can develop plans with the most efficient delivery parameters – cutting beam-on time in half compared with manual forward planning .
To learn more , check out the business line update from Verena Schiller , president , neuroscience solutions , on Monday 26 October at 2.00 p.m .
ET .
To expand its offering of cloud-based solutions for advanced radiotherapy , in @ @ @ @ @ @ @ customers access to high-quality , cloud-based , treatment planning analytics .
ProKnow can store , navigate and retrieve data in a scalable cloud-based framework that works across all imaging , planning and treatment modalities .
A wealth of insight is contained within these data ; but without simple , intuitive solutions , it remains locked away .
By centralizing data in a secure web-based repository , ProKnow can unlock it and make it accessible , enabling providers to connect to clinical teams anywhere , any time .
To learn more , check out @ @ @ @ @ @ @ , founder of ProKnow , on Friday 23 October at 2.00 p.m .
ET .
In May 2020 , Elekta announced its acquisition of Kaiku Health* , a Finnish company best known for its app that monitors patient-reported outcomes .
The Kaiku Health app provides intelligent symptom tracking and management for healthcare providers in routine oncology care and clinical studies .
The app screens for patients ’ symptoms , notifies the care team on their development and provides personalized support for patients .
It is easily implemented into existing hospital information systems and @ @ @ @ @ @ @ MOSAIQ oncology information system .
Including intelligent patient-monitoring software in the Elekta portfolio supports the company ’ s oncology informatics strategy .
This is a concrete step toward expanding its digital portfolio to further digitally connect customers and their patients .
To learn more , check out the breakout session presented by Vesa Kataja , chief medical officer , Kaiku Health , on Friday 23 October at noon ET .
With industry events such as the ASTRO Annual Meeting , the SROA Annual Meeting and the ASRT 2020 radiation therapy conference going completely @ @ @ @ @ @ @ .
For starters , Elekta is partnering with ASTRO for the very first virtual ASTRO experience .
Alongside hosting a booth in the virtual exhibit hall , showcasing the abovementioned products , Elekta is running its virtual User Meeting 2020 on 23 October .
Attendees at this event will hear from peers , industry experts and Elekta product specialists in a day of learning , networking and interactive product demonstrations .
The User Meeting will conclude with the session , Championing Women & Diversity in Radiation Oncology—A Panel Discussion .
This virtual discussion @ @ @ @ @ @ @ Cervino from Memorial Sloan Kettering Cancer Center ; Sandra Hayden from the University of Texas Southwestern Medical Center ; Lisa Kachnic from Columbia University Medical Center and the Herbert Irving Comprehensive Cancer Center ; Toral Patel from the University of Texas Southwestern Medical Center ; and Crystal Seldon from the University of Miami/Jackson Memorial Hospital .
In the afternoon breakout sessions , radiation oncologists and medical physicists will share their experiences of treating patients on the Elekta Unity and implementing an MR-guided radiotherapy programme .
In the field of stereotactic radiotherapy , speakers @ @ @ @ @ @ @ for maximizing SRS efficacy and efficiency with the Leksell Gamma Knife Icon .
Attendees can also hear presentations on skin brachytherapy , Elekta ’ s latest digital solutions , and its recent acquisitions : Kaiku Health and ProKnow .
There ’ s also a discussion on the role of education and training in the medical technology industry .
Elekta is also attending the Virtual Annual Meeting of the Society of Radiation Oncology Administrators ( SROA ) .
During the meeting , Elekta will participate in a payer trend roundtable , on 27 October @ @ @ @ @ @ @ by a “ Brown bag ” webinar at 4.00 p.m .
ET , to share how it is innovating personalized care solutions on a global scale .
As a long-time partner of the American Society of Radiologic Technologists ( ASRT ) , Elekta is participating in the educational sessions at the ASRT 2020 radiation therapy conference and will be hosting a virtual booth at the ASRT expo .
Click here for a list of all of Elekta ’ s virtual events .
*MOSAIQ Plaza , ProKnow and Kaiku Health are not available in @ @ @ @ @ @ @ is not yet commercially available .

The Elekta Unity MR-linac now offers biologic assessment of tumour response during therapy.
From software launches to new radiation therapy equipment, Elekta continues to innovate in the field of cancer-treatment technologies. The company has released, acquired and gained regulatory approval for a range of new radiotherapy products over the last 12 months.
What’s new?
In December 2019, Elekta received 510(k) pre-market notification from the US Food and Drug Administration (FDA) for the use of diffusion-weighted imaging (DWI) datasets obtained with the Elekta Unity MR-linac. This approval expanded the clinical utility of Elekta Unity to include biologic assessment of tumour response during therapy, allowing treatment adaptation based, not just on gross anatomic changes, but also on early biologic changes at the cellular level.
DWI works by creating a map of the diffusion of water molecules at the cellular level, which can be processed to generate the apparent diffusion coefficient (ADC). A growing body of evidence shows that changes in ADC within a tumour can provide important insights into an individual’s tumour response. Such insights, which were previously unavailable during radiation treatment, can support further personalization of the radiotherapy regimen by allowing more tailored dose adaptation. Overall, DWI can improve a clinician’s ability to deliver the right dose to the right part of the tumour.
To learn more, check out the business line update from Lionel Hadjabjeda, president, MR-Linac solutions, on Wednesday 28 October at 12.00 p.m. ET.
MOSAIQ Plaza helps to deliver value-based healthcare.
Elekta’s MOSAIQ Plaza* is a powerful, comprehensive set of digital tools that connects users to their colleagues, data and patients, throughout the entire patient workflow. This fully integrated software suite helps to drive efficiencies, standardize daily practice and deliver value-based healthcare.
For example, Elekta recently acquired and continued development of the technology behind MOSAIQ Voice, which enables users to work at the speed of their voice. The tool allows clinical tasks in MOSAIQ to be completed via dictation, streamlining documentation and reducing workload.
Another game-changing workflow advancement is MOSAIQ SmartClinic. With a wide range of professionals involved in cancer patient care, MOSAIQ SmartClinic provides a transparent approach to care management, connecting users to the information that they need, whenever and wherever.
To learn more, check out the business line update from Andrew Wilson, president, oncology informatics solutions, on Tuesday 27 October at 12.00 p.m. ET.
The Geneva brachytherapy applicator.
Cervical cancer screening, via Pap and HPV tests, has successfully reduced the incidence of cervical cancer via early detection. But for women still confronted with this disease, treatments such as brachytherapy offer a proven way to improve overall survival. In April 2000. Elekta introduced the Geneva brachytherapy applicator. Designed for cervical cancer up to stage IIB, Geneva could help up to 75% of patients with locally advanced cervical cancer.
In mid-July, Geneva received FDA 510(k) clearance. With a comprehensive range of ovoid (13–40 mm) and intrauterine tube (30–80 mm) sizes, in addition to a new interstitial intrauterine tube to expand treatment options after hysterectomy, Geneva can accommodate most female anatomies. Clinicians can now take advantage of a single gynaecological applicator to treat most cervical cancer patients via intracavitary and/or interstitial brachytherapy.
To learn more, check out the business line update from John Lapré, president, brachytherapy solutions, on Tuesday 27 October at 2.00 p.m. ET.
Leksell Gamma Knife Lightning provides dose optimization at lightning speed.
On 12 June, Elekta introduced Leksell Gamma Knife Lightning**, a treatment optimizer designed to boost Gamma Knife radiosurgery workflows and improve plan quality. Lightning, which has been available commercially since the end of June, enables clinicians to create plans for multiple targets in less than a minute and to include beam-on time as a constraint, greatly reducing overall treatment time.
Gamma Knife Lightning addresses the challenge of increasing automation and speed in the stereotactic radiosurgery workflow, while also ensuring a personalized plan tailored to each patient’s needs. The ability to create multiple plans in less than 60 s will allow physicians to compare plans and select the best option. And by controlling beam-on time, they can develop plans with the most efficient delivery parameters – cutting beam-on time in half compared with manual forward planning.
To learn more, check out the business line update from Verena Schiller, president, neuroscience solutions, on Monday 26 October at 2.00 p.m. ET.
ProKnow offers access to high-quality, cloud-based analytics.
To expand its offering of cloud-based solutions for advanced radiotherapy, in late-August 2019 Elekta acquired ProKnow*, offering customers access to high-quality, cloud-based, treatment planning analytics. ProKnow can store, navigate and retrieve data in a scalable cloud-based framework that works across all imaging, planning and treatment modalities. A wealth of insight is contained within these data; but without simple, intuitive solutions, it remains locked away. By centralizing data in a secure web-based repository, ProKnow can unlock it and make it accessible, enabling providers to connect to clinical teams anywhere, any time.
To learn more, check out the breakout session presented by Ben Nelms, founder of ProKnow, on Friday 23 October at 2.00 p.m. ET.
The Kaiku Health app.
In May 2020, Elekta announced its acquisition of Kaiku Health*, a Finnish company best known for its app that monitors patient-reported outcomes. The Kaiku Health app provides intelligent symptom tracking and management for healthcare providers in routine oncology care and clinical studies. The app screens for patients’ symptoms, notifies the care team on their development and provides personalized support for patients. It is easily implemented into existing hospital information systems and can be integrated with Elekta’s MOSAIQ oncology information system.
Including intelligent patient-monitoring software in the Elekta portfolio supports the company’s oncology informatics strategy. This is a concrete step toward expanding its digital portfolio to further digitally connect customers and their patients.
To learn more, check out the breakout session presented by Vesa Kataja, chief medical officer, Kaiku Health, on Friday 23 October at noon ET.
Virtual presence
With industry events such as the ASTRO Annual Meeting, the SROA Annual Meeting and the ASRT 2020 radiation therapy conference going completely virtual this year, so has Elekta.
For starters, Elekta is partnering with ASTRO for the very first virtual ASTRO experience. Alongside hosting a booth in the virtual exhibit hall, showcasing the abovementioned products, Elekta is running its virtual User Meeting 2020 on 23 October. Attendees at this event will hear from peers, industry experts and Elekta product specialists in a day of learning, networking and interactive product demonstrations.
The User Meeting will conclude with the session, Championing Women & Diversity in Radiation Oncology—A Panel Discussion. This virtual discussion will include five trailblazing professionals: Laura Cervino from Memorial Sloan Kettering Cancer Center; Sandra Hayden from the University of Texas Southwestern Medical Center; Lisa Kachnic from Columbia University Medical Center and the Herbert Irving Comprehensive Cancer Center; Toral Patel from the University of Texas Southwestern Medical Center; and Crystal Seldon from the University of Miami/Jackson Memorial Hospital.
In the afternoon breakout sessions, radiation oncologists and medical physicists will share their experiences of treating patients on the Elekta Unity and implementing an MR-guided radiotherapy programme. In the field of stereotactic radiotherapy, speakers will discuss linac-based stereotactic treatments and strategies for maximizing SRS efficacy and efficiency with the Leksell Gamma Knife Icon. Attendees can also hear presentations on skin brachytherapy, Elekta’s latest digital solutions, and its recent acquisitions: Kaiku Health and ProKnow. There’s also a discussion on the role of education and training in the medical technology industry.
Elekta is also attending the Virtual Annual Meeting of the Society of Radiation Oncology Administrators (SROA). During the meeting, Elekta will participate in a payer trend roundtable, on 27 October at 3.00 p.m. ET, followed by a “Brown bag” webinar at 4.00 p.m. ET, to share how it is innovating personalized care solutions on a global scale.
As a long-time partner of the American Society of Radiologic Technologists (ASRT), Elekta is participating in the educational sessions at the ASRT 2020 radiation therapy conference and will be hosting a virtual booth at the ASRT expo.
Click here for a list of all of Elekta’s virtual events.
*MOSAIQ Plaza, ProKnow and Kaiku Health are not available in all markets.
**Leksell Gamma Knife Lightning is not yet commercially available.


physicsworld--2020-10-22--Conductive hydrogel could repair damaged peripheral nerves - Physics World

Researchers in China have developed a stretchable and conductive hydrogel that they claim could one day be used to repair peripheral nerves – delicate tissues that transmit bioelectrical signals from the brain to the rest of the body in real time .
The hydrogel , which has been tested in rats with sciatic nerve injuries , remains electrically conducting when elongated and its conductivity improves when it is illuminated with near-infrared light .
These two properties mean that it could be used to treat serious peripheral nerve injury , especially when the missing nerve length exceeds 10 mm .
Flexible @ @ @ @ @ @ @ bounds in the last few decades , allowing bioelectronic materials to be used as artificial tissue in vivo .
Hydrogels – 3D polymer networks that can hold a large amount of water – are similar in structure to nerve tissue , and interfacing these materials to living tissue is one of the most important topics in bioelectronics today .
Peripheral nerve injury – for example , when a peripheral nerve has been completely severed in an accident – can result in chronic pain , neurological disorders , paralysis and even disability .
Such @ @ @ @ @ @ @ treat .
One of the main techniques used to repair injured peripheral nerves is autologous nerve transplantation .
This involves removing a section of peripheral nerve from elsewhere in the body and “ sewing ” it onto the ends of the severed nerve .
There are nevertheless some shortcomings associated with this approach , including the fact that the surgery doesn ’ t always restore nerve function and that multiple follow-up procedures are sometimes required .
There is also the risk of painful neuroma ( benign growth of nerve tissue ) after the @ @ @ @ @ @ @ engineering to restore and repair motor and sensory function of neuronal cells .
This method makes use of natural or synthetic materials that can be grafted onto nerve cells together with “ supporting ” cells , such as mesenchymal stem cells .
The problem with this approach is that the grafted nerves recover slowly .
The research team – led by Qun-Dong Shen of Nanjing University , Chang-Chun Wang of the Nanjing Institute of Technology and Ze-Zhang Zhu of the Affiliated Drum Tower Hospital of Nanjing University – has now developed an alternative @ @ @ @ @ @ @ researchers made use of a mechanically tough but stretchable conductive hydrogel containing biocompatible polymers : polyacrylamide and conductive polyaniline .
These crosslinked polymers boast a 3D microporous network that , once implanted , allows nerve cells to enter and adhere , helping to restore lost tissue .
The hydrogel conducts bioelectric signals – something that the team proved by replacing a damaged sciatic nerve from a toad with the material and measuring the signals through it .
They also implanted the hydrogel into rats with sciatic nerve injuries .
In these experiments , @ @ @ @ @ @ @ recovered their bioelectrical properties – as measured by electromyography one to eight weeks following the operation – and that their walking improved compared with rats that hadn ’ t been treated with the hydrogel .
Another advantage of the hydrogel is that the current flowing through it increases from 1.95 nA to 2.3 nA when it is irradiated with near-infrared light , which can penetrate deep into biological tissue .
This proves that the hydrogel is relatively sensitive to light of this wavelength , say the researchers , and that the bioelectrical signal @ @ @ @ @ @ @ this way , so allowing for improved nerve conduction and recovery .
And that is not all : when elongated mechanically , the material remains conducting – just like biological nerve tissue .
This means that it can accommodate the large strains produced by sutured nerve tissue in motion .
Full details of the research are published in ACS Nano .

A highly flexible and NIR-responsive conducting polymer hydrogel could repair serious injuries to peripheral nerves. (Courtesy: ACS Nano 10.1021/acsnano.0c05197 ©2020 American Chemical Society)
Researchers in China have developed a stretchable and conductive hydrogel that they claim could one day be used to repair peripheral nerves – delicate tissues that transmit bioelectrical signals from the brain to the rest of the body in real time. The hydrogel, which has been tested in rats with sciatic nerve injuries, remains electrically conducting when elongated and its conductivity improves when it is illuminated with near-infrared light. These two properties mean that it could be used to treat serious peripheral nerve injury, especially when the missing nerve length exceeds 10 mm.
Flexible electronics has come along in leaps and bounds in the last few decades, allowing bioelectronic materials to be used as artificial tissue in vivo. Hydrogels – 3D polymer networks that can hold a large amount of water – are similar in structure to nerve tissue, and interfacing these materials to living tissue is one of the most important topics in bioelectronics today.
Repairing injured peripheral nerves
Peripheral nerve injury – for example, when a peripheral nerve has been completely severed in an accident – can result in chronic pain, neurological disorders, paralysis and even disability. Such injuries, however, are difficult to treat.
One of the main techniques used to repair injured peripheral nerves is autologous nerve transplantation. This involves removing a section of peripheral nerve from elsewhere in the body and “sewing” it onto the ends of the severed nerve. There are nevertheless some shortcomings associated with this approach, including the fact that the surgery doesn’t always restore nerve function and that multiple follow-up procedures are sometimes required. There is also the risk of painful neuroma (benign growth of nerve tissue) after the operation.
Another technique relies on tissue engineering to restore and repair motor and sensory function of neuronal cells. This method makes use of natural or synthetic materials that can be grafted onto nerve cells together with “supporting” cells, such as mesenchymal stem cells. The problem with this approach is that the grafted nerves recover slowly.
Hydrogel conducts bioelectric signals
The research team – led by Qun-Dong Shen of Nanjing University, Chang-Chun Wang of the Nanjing Institute of Technology and Ze-Zhang Zhu of the Affiliated Drum Tower Hospital of Nanjing University – has now developed an alternative technique. In their work, the researchers made use of a mechanically tough but stretchable conductive hydrogel containing biocompatible polymers: polyacrylamide and conductive polyaniline. These crosslinked polymers boast a 3D microporous network that, once implanted, allows nerve cells to enter and adhere, helping to restore lost tissue.
Scanning electron microscopy image of the conductive polymer hydrogel. (Courtesy: ACS Nano 2020 10.1021/acsnano.0c05197)
The hydrogel conducts bioelectric signals – something that the team proved by replacing a damaged sciatic nerve from a toad with the material and measuring the signals through it. They also implanted the hydrogel into rats with sciatic nerve injuries. In these experiments, they observed that the rats’ nerves recovered their bioelectrical properties – as measured by electromyography one to eight weeks following the operation – and that their walking improved compared with rats that hadn’t been treated with the hydrogel.
Another advantage of the hydrogel is that the current flowing through it increases from 1.95 nA to 2.3 nA when it is irradiated with near-infrared light, which can penetrate deep into biological tissue. This proves that the hydrogel is relatively sensitive to light of this wavelength, say the researchers, and that the bioelectrical signal through the material can be increased in this way, so allowing for improved nerve conduction and recovery.
And that is not all: when elongated mechanically, the material remains conducting – just like biological nerve tissue. This means that it can accommodate the large strains produced by sutured nerve tissue in motion.
Full details of the research are published in ACS Nano.


physicsworld--2020-10-22--‘Quintuple point’ material defies 150-year-old thermodynamics rule - Physics World

Five different phases of a colloid-polymer mixture can co-exist at the same time , in defiance of the 150-year-old Gibbs phase rule , which states that only three simultaneous phases are possible .
The result , which researchers in France and the Netherlands obtained using an algebraic model for the thermodynamics of binary rod-polymer mixtures , could help advance our understanding of phase transitions in complex systems , with possible industrial applications in areas such as food processing and paint manufacture .
The American physicist Josiah Willard Gibbs is an acknowledged founder of modern thermodynamics and physical chemistry .
His @ @ @ @ @ @ @ the 1870s , sets out the maximum number of different phases that can simultaneously exist in a substance or mixture of substances .
For pure substances , Gibbs ’ phase rule predicts a maximum of three phases .
One well-known example is water , which can co-exist as a liquid , solid and gas at its so-called triple point .
In the new work , a team led by Remco Tuinier of the Eindhoven University of Technology simulated the behaviour of a colloidal mixture of two particle types – rods and polymers – @ @ @ @ @ @ @ their computations , they represented rods as hard spherocylinders and the polymers as spheres that freely overlap with each other .
“ The system can increase the space available for the polymer chains by clustering the rods together , ” Tuinier explains .
“ This results in a phase separation in the mixture into two ( or more ) phases containing a phase where the rods are enriched and another area that mainly contains polymers.
” Once this clustering occurs , the heavier rods sink to the bottom of the mixture , leading @ @ @ @ @ @ @ part of the mixture becomes so crowded that the rods take up preferential positions so that they are “ less in each other ’ s way ” , Tuinier tells Physics World .
The rods thus end up neatly arranged next to each other .
Building on previous models for dispersions of pure rods and disk-polymer mixtures , the researchers developed a quantitative theory to map out a complete phase diagram for their two-component rod-polymer mixtures .
According to the calculations of team member Vincent Peters , up to five different phases appear @ @ @ @ @ @ @ ( see image ) .
At this “ quintuple point ” , the possibilities are an isotropic gas phase with unaligned rods at the top ; a nematic liquid crystal phase with rods pointing in roughly the same direction ; a smectic liquid crystal phase with rods lying in different layers ; and two solid phases with “ ordinary ” crystals at the bottom .
This five-phase system represents “ the first time that the famous Gibbs rule has been broken , ” team member Mark Vis says .
The profusion of phases @ @ @ @ @ @ @ of the shape of the particles ( particularly their length and diameter ) , which Gibbs did not consider .
“ In addition to the known variables of temperature and pressure , you get two additional variables : the length of the particle in relation to its diameter , and the diameter of the particle in relation to the diameter of other particles in the solution , ” he explains .
As sometimes happens in science , the result was in part a stroke of luck , since the researchers weren ’ t @ @ @ @ @ @ @ in their simulations .
While studying plate-shaped particles and polymers , however , team member Álvaro González García and Vincent Peters observed a four-phase equilibrium .
“ Álvaro came to me one day and asked me what had gone wrong , because four phases just couldn ’ t be right , ” Tuinier says .
While the team obtained its results using simulations , members say that a real version of their system could easily be produced in the laboratory , and the results tested in experiments .
According to Vis , the @ @ @ @ @ @ @ our understanding of phase transitions in such systems and predict more precisely when phase transitions occur – knowledge that could come in useful for applications such as manufacturing complex colloidal mixtures like mayonnaise or paint .
Liquid crystals in displays could benefit too , Vis adds .
“ Most industries choose to work with a single-phase system , where there is no segregation , ” he says .
“ But if the exact transitions are clearly described , then the industry can actually use those different phases instead of avoiding them.
” The @ @ @ @ @ @ @ .

A five-phase equilibrium. Image: ICMS animation studio
Five different phases of a colloid-polymer mixture can co-exist at the same time, in defiance of the 150-year-old Gibbs phase rule, which states that only three simultaneous phases are possible. The result, which researchers in France and the Netherlands obtained using an algebraic model for the thermodynamics of binary rod-polymer mixtures, could help advance our understanding of phase transitions in complex systems, with possible industrial applications in areas such as food processing and paint manufacture.
The American physicist Josiah Willard Gibbs is an acknowledged founder of modern thermodynamics and physical chemistry. His phase rule, which he derived in the 1870s, sets out the maximum number of different phases that can simultaneously exist in a substance or mixture of substances. For pure substances, Gibbs’ phase rule predicts a maximum of three phases. One well-known example is water, which can co-exist as a liquid, solid and gas at its so-called triple point.
Clustering effect
In the new work, a team led by Remco Tuinier of the Eindhoven University of Technology simulated the behaviour of a colloidal mixture of two particle types – rods and polymers – dispersed in a background solvent. In their computations, they represented rods as hard spherocylinders and the polymers as spheres that freely overlap with each other.
“The system can increase the space available for the polymer chains by clustering the rods together,” Tuinier explains. “This results in a phase separation in the mixture into two (or more) phases containing a phase where the rods are enriched and another area that mainly contains polymers.”
Once this clustering occurs, the heavier rods sink to the bottom of the mixture, leading to segregation. Eventually, the lower part of the mixture becomes so crowded that the rods take up preferential positions so that they are “less in each other’s way”, Tuinier tells Physics World. The rods thus end up neatly arranged next to each other.
A quintuple point emerges
Building on previous models for dispersions of pure rods and disk-polymer mixtures, the researchers developed a quantitative theory to map out a complete phase diagram for their two-component rod-polymer mixtures. According to the calculations of team member Vincent Peters, up to five different phases appear in the system under a specific condition (see image). At this “quintuple point”, the possibilities are an isotropic gas phase with unaligned rods at the top; a nematic liquid crystal phase with rods pointing in roughly the same direction; a smectic liquid crystal phase with rods lying in different layers; and two solid phases with “ordinary” crystals at the bottom.
This five-phase system represents “the first time that the famous Gibbs rule has been broken,” team member Mark Vis says. The profusion of phases is possible, Tuinier adds, because of the shape of the particles (particularly their length and diameter), which Gibbs did not consider. “In addition to the known variables of temperature and pressure, you get two additional variables: the length of the particle in relation to its diameter, and the diameter of the particle in relation to the diameter of other particles in the solution,” he explains.
Serendipitous result
As sometimes happens in science, the result was in part a stroke of luck, since the researchers weren’t initially looking for more than three phases in their simulations. While studying plate-shaped particles and polymers, however, team member Álvaro González García and Vincent Peters observed a four-phase equilibrium. “Álvaro came to me one day and asked me what had gone wrong, because four phases just couldn’t be right,” Tuinier says.
While the team obtained its results using simulations, members say that a real version of their system could easily be produced in the laboratory, and the results tested in experiments. According to Vis, the team’s findings could help advance our understanding of phase transitions in such systems and predict more precisely when phase transitions occur – knowledge that could come in useful for applications such as manufacturing complex colloidal mixtures like mayonnaise or paint.
Liquid crystals in displays could benefit too, Vis adds. “Most industries choose to work with a single-phase system, where there is no segregation,” he says. “But if the exact transitions are clearly described, then the industry can actually use those different phases instead of avoiding them.”
The research is detailed in Physical Review Letters.