New starfish-like fossil reveals evolution in action

Researchers from the University of Cambridge have discovered a fossil of the earliest starfish-like animal, which helps us understand the origins of the nimble-armed creature.

The prototype starfish, which has features in common with both sea lilies and modern-day starfish, is a missing link for scientists trying to piece together its early evolutionary history.

The exceptionally preserved fossil, named Cantabrigiaster fezouataensis, was discovered in Morroco’s Anti-Atlas mountain range. Its intricate design — with feathery arms akin to a lacework — has been frozen in time for roughly 480 million years.

The new species is unusual because it doesn’t have many of the key features of its contemporary relatives, lacking roughly 60% of a modern starfish’s body plan.

The fossil’s features are instead a hybrid between those of a starfish and a sea lily or crinoid — not a plant but a wavy-armed filter feeder which fixes itself to the seabed via a cylindrical ‘stem’.

The discovery, reported in Biology Letters, captures the early evolutionary steps of the animal at a time in Earth’s history when life suddenly expanded, a period known as the Ordovician Biodiversification Event.

The find also means scientists can now use the new find as a template to work out how it evolved from this more basic form to the complexity of their contemporaries.

“Finding this missing link to their ancestors is incredibly exciting. If you went back in time and put your head under the sea in the Ordovician then you wouldn’t recognize any of the marine organisms — except the starfish, they are one of the first modern animals,” said lead author Dr Aaron Hunter, a visiting postdoctoral researcher in the Department of Earth Sciences.

Modern starfish and brittle stars are part of a family of spiny-skinned animals called the echinoderms which, although they don’t have a backbone, are one of the closest group of animals to vertebrates. Crinoids, and otherworldly creatures like the sea urchins and sea cucumbers are all echinoderms.

The origin of starfish has eluded scientists for decades. But the new species is so well preserved that its body can finally be mapped in detail and its evolution understood. “The level of detail in the fossil is amazing — its structure is so complex that it took us a while to unravel its significance,” said Hunter.

It was Hunter’s work on both living and fossil echinoderms that helped him spot its hybrid features. “I was looking at a modern crinoid in one of the collections at the Western Australian Museum and I realised the arms looked really familiar, they reminded me of this unusual fossil that I had found years earlier in Morocco but had found difficult to work with,” he said.

Fezouata in Morocco is something of a holy grail for palaeontologists — the new fossil is just one of the many remarkably well preserved soft-bodied animals uncovered from the site.

Hunter and co-author Dr Javier Ortega-Hernández, who was previously based at Cambridge’s Department of Zoology and is now based at Harvard University, named the species Cantabrigiaster in honour of the long history of echinoderm research at their respective institutions.

Hunter and Ortega-Hernández examined their new species alongside a catalogue of hundreds starfish-like animals. They indexed all of their body structures and features, building a road map of the echinoderm skeleton which they could use to assess how Cantabrigiaster was related to other family members.

Modern echinoderms come in many shapes and sizes, so it can be difficult to work out how they are related to one another. The new analysis, which uses extra-axial theory — a biology model usually only applied to living species — meant that Hunter and Ortega-Hernández could identify similarities and differences between the body plan of modern echinoderms and then figure out how each family member was linked to their Cambrian ancestors.

They found that only the key or axial part of the body, the food groove — which funnels food along each of the starfish’s arms — was present in Cantabrigiaster. Everything outside this, the extra-axial body parts, were added later.

The authors plan to expand their work in search of early echinoderms. “One thing we hope to answer in the future is why starfish developed their five arms,” said Hunter. “It seems to be a stable shape for them to adopt — but we don’t yet know why. We still need to keep searching for the fossil that gives us that particular connection, but by going right back to the early ancestors like Cantabrigiaster we are getting closer to that answer.”

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Covid: ‘No evidence’ virus levels decreasing in England

Imperial College London research suggests rates may have risen over the first 10 days of the third lockdown.

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Hematopoietic stem cell transplants may provide long-term benefit for people with MS

A new study shows that intense immunosuppression followed by a hematopoietic stem cell transplant may prevent disability associated with multiple sclerosis (MS) from getting worse in 71% of people with relapsing-remitting MS for up to 10 years after the treatment. The research is published in the January 20, 2021, online issue of Neurology®, the medical journal of the American Academy of Neurology. The study also found that in some people their disability improved over 10 years after treatment. Additionally, more than half of the people with the secondary progressive form of MS experienced no worsening of their symptoms 10 years after a transplant.

While most people with MS are first diagnosed with relapsing-remitting MS, marked by symptom flare-ups followed by periods of remission, many people with relapsing-remitting MS eventually transition to secondary progressive MS, which does not have wide swings in symptoms but instead a slow, steady worsening of the disease.

The study involved autologous hematopoietic stem cell transplants, which use healthy blood stem cells from the participant’s own body to replace diseased cells.

“So far, conventional treatments have prevented people with MS from experiencing more attacks and worsening symptoms, but not in the long term,” said study author Matilde Inglese, M.D., Ph.D., of the University of Genoa in Italy and a member of the American Academy of Neurology. “Previous research shows more than half of the people with MS who take medication for their disease still get worse over a 10-year period. Our results are exciting because they show hematopoietic stem cell transplants may prevent someone’s MS disabilities from getting worse over the longer term.”

The study looked at 210 people with MS who received stem cell transplants from 1997 to 2019. Their average age was 35. Of those people, 122 had relapsing-remitting MS and 86 had secondary progressive MS and two had primary progressive MS.

Researchers assessed participants at six months, five years and 10 years after their transplants.

Five years into the study, researchers found that 80% of the people experienced no worsening of their MS disability. At the 10-year mark, 66% still had not experienced a worsening of disability.

When looking at just the people with the most common form of MS, researchers found 86% of them experienced no worsening of their disability five years after their transplant. Ten years later, 71% still experienced no worsening of their disability.

Also, people with progressive MS benefited from stem cell transplants. Researchers found that 71% of the people with this type of MS experienced no worsening of their disability five years after their transplants. Ten years later, 57% experienced no worsening of their disability.

“Our study demonstrates that intense immunosuppression followed by hematopoietic stem cell transplants should be considered as a treatment for people with MS, especially those who don’t respond to conventional therapy,” Inglese said.

Limitations of the study include that it was retrospective, did not include a control group and the clinicians who helped measure participants’ disability were aware that they had received stem cell transplants, so that could have led to bias. Inglese said these limitations will be addressed in future research.

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Materials provided by American Academy of Neurology. Note: Content may be edited for style and length.

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Brain pressure disorder that causes headache, vision problems on rise

A new study has found a brain pressure disorder called idiopathic intracranial hypertension is on the rise, and the increase corresponds with rising obesity rates. The study is published in the January 20, 2021, online issue of Neurology®, the medical journal of the American Academy of Neurology. The study also found that for women, socioeconomic factors like income, education and housing may play a role in their risk.

Idiopathic intracranial hypertension is when the pressure in the fluid surrounding the brain rises. It can mimic the symptoms of a brain tumor, causing chronic, disabling headaches, vision problems and in rare cases, vision loss. It is most often diagnosed in women of childbearing age. Treatment is often weight loss. In some cases, surgery may be required.

“The considerable increase in idiopathic intracranial hypertension we found may be due to many factors but likely mostly due to rising obesity rates,” said study author William Owen Pickrell, Ph.D., M.R.C.P., of Swansea University in Wales in the United Kingdom and a member of the American Academy of Neurology. “What is more surprising from our research is that women who experience poverty or other socioeconomic disadvantages may also have an increased risk independent of obesity.”

For the study, researchers used a national healthcare database in Wales to analyze 35 million patient years of data over a 15-year period, between 2003 and 2017. They identified 1,765 people with idiopathic intracranial hypertension during that time. Of the group, 85% were women. Researchers recorded body mass index measurements for study participants. Body mass index is calculated by dividing weight by height. For every one person with the disorder, researchers compared three people without it who were matched for gender, age and socioeconomic status.

The socioeconomic status of each person with the disorder was determined by where they live, using a national scoring system that considers factors like income, employment, health, education and access to services. People in the study were then divided into five groups ranging from those with the fewest socioeconomic advantages to those with the most.

Overall, researchers found a six-fold increase in the number of cases of the disorder over the course of the study. In 2003, for every 100,000 people, 12 were living with the disorder, compared to 76 people in 2017. Also, in 2013, for every 100,000 people, two were diagnosed during that year, compared to eight people in 2017.

Researchers found that the increasing number of people living with the disorder corresponded to rising obesity rates in Wales during the study, with 29% of the population being obese in 2003 compared to 40% in 2017.

“The worldwide prevalence of obesity nearly tripled between 1975 and 2016, so while our research looked specifically at people in Wales, our results may also have global relevance,” said Pickrell.

There were strong links for both men and women between body mass index and risk of the disorder. For women, there were 180 cases per 100,000 people during the study for those with high body mass index compared to 13 women with a body mass index considered to be ideal. For men, there were 21 cases per 100,000 among those with a high body mass index compared to eight cases for those with an ideal body mass index.

Researchers also found that for women only, socioeconomic factors were linked to risk. There were 452 women in the group with the fewest socioeconomic advantages compared to 197 in the group with the most. The women in the group with the fewest had a 1.5 times greater risk of developing the disorder than women in the group with the most, even after adjusting for body mass index.

“Of the five socioeconomic groups of our study participants, women in the lowest two groups made up more than half of the female participants in the study,” said Pickrell. “More research is needed to determine which socioeconomic factors such as diet, pollution, smoking or stress may play a role in increasing a woman’s risk of developing this disorder.”

A limitation of the study was that researchers identified the socioeconomic status of participants by the regions in which they lived instead of obtaining individual socioeconomic information for each participant.

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Rollout of daily testing of close contacts paused in English schools

More work is needed to understand its benefits in schools in England given the new variant, health officials say.

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Birmingham and Nottinghamshire trusts offer 24-hour Covid vaccines

The vaccines will be offered to existing high-priority groups and hospital staff on night shifts.

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NHS child gender clinic rated ‘inadequate’ by inspectors

Services and waiting times must improve at the NHS’s child gender-identity service, inspectors say.

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Covid: ‘Sharp drop’ in heart-attack hospital admissions

Some people who need urgent help appear to be staying away, as in the first peak, say researchers.

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Light-controlled Higgs modes found in superconductors; potential sensor, computing uses

Even if you weren’t a physics major, you’ve probably heard something about the Higgs boson.

There was the title of a 1993 book by Nobel laureate Leon Lederman that dubbed the Higgs “The God Particle.” There was the search for the Higgs particle that launched after 2009’s first collisions inside the Large Hadron Collider in Europe. There was the 2013 announcement that Peter Higgs and Francois Englert won the Nobel Prize in Physics for independently theorizing in 1964 that a fundamental particle — the Higgs — is the source of mass in subatomic particles, making the universe as we know it possible.

(Plus, there are the Iowa State University physicists on the author list of a 2012 research paper describing how the ATLAS Experiment at the collider observed a new particle later confirmed to be the Higgs.)

And now Jigang Wang, a professor of physics and astronomy at Iowa State and a senior scientist at the U.S. Department of Energy’s Ames Laboratory, and a team of researchers have discovered a form of the famous particle within a superconductor, a material capable of conducting electricity without resistance, generally at very cold temperatures.

Wang and his collaborators — including Chang-Beom Eom, the Raymond R. Holton Chair for Engineering and Theodore H. Geballe Professor at the University of Wisconsin-Madison; Ilias Perakis, professor and chair of physics at the University of Alabama at Birmingham; and Eric Hellstrom, professor and interim chair of mechanical engineering at Florida State University — report the details in a paper recently published online by the journal Nature Communications.

They write that in lab experiments they’ve found a short-lived “Higgs mode” within iron-based, high-temperature (but still very cold), multi-energy band, unconventional superconductors.

A quantum discovery

This Higgs mode is a state of matter found at the quantum scale of atoms, their electronic states and energetic excitations. The mode can be accessed and controlled by laser light flashing on the superconductor at terahertz frequencies of trillions of pulses per second. The Higgs modes can be created within different energy bands and still interact with each other.

Wang said this Higgs mode within a superconductor could potentially be used to develop new quantum sensors.

“It’s just like the Large Hadron Collider can use the Higgs particle to detect dark energy or antimatter to help us understand the origin of the universe,” Wang said. “And our Higgs mode sensors on the table-top have the potential help us discover the hidden secrets of quantum states of matter.”

That understanding, Wang said, could advance a new “quantum revolution” for high-speed computing and information technologies.

“It’s one way this exotic, strange, quantum world can be applied to real life,” Wang said.

Light control of superconductors

The project takes a three-pronged approach to accessing and understanding the special properties, such as this Higgs mode, hidden within superconductors:

Wang’s research group uses a tool called quantum terahertz spectroscopy to visualize and steer pairs of electrons moving through a superconductor. The tool uses laser flashes as a control knob to accelerate supercurrents and access new and potentially useful quantum states of matter.

Eom’s group developed the synthesis technique that produces crystalline thin films of the iron-based superconductor with high enough quality to reveal the Higgs mode. Hellstrom’s group developed deposition sources for the iron-based superconducting thin film development.

Perakis’ group led the development of quantum models and theories to explain the results of the experiments and to simulate the salient features that come from the Higgs mode.

The work has been supported by a grant to Wang from the National Science Foundation and grants to Eom and Perakis from the U.S. Department of Energy.

“Interdisciplinary science is the key here,” Perakis said. “We have quantum physics, materials science and engineering, condensed matter physics, lasers and photonics with inspirations from fundamental, high-energy and particle physics.”

There are good, practical reasons for researchers in all those fields to work together on the project. In this case, students from the four research groups worked together with their advisors to accomplish this discovery.

“Scientists and engineers,” Wang wrote in a research summary, “have recently come to realize that certain materials, such as superconductors, have properties that can be exploited for applications in quantum information and energy science, e.g., processing, recording, storage and communication.”

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Fastener with microscopic mushroom design holds promise

A Velcro-like fastener with a microscopic design that looks like tiny mushrooms could mean advances for everyday consumers and scientific fields like robotics.

In Biointerphases, published by AIP Publishing, researchers from Wageningen University in the Netherlands show how the design can use softer materials and still be strong enough to work.

Probabilistic fasteners work, because they are designed with a tiny pattern on one surface that interlocks with features on the other surface. Currently available fasteners, like Velcro and 3M, are called hook and loop fasteners. That design requires harder, stiff material, which is what causes the loud ripping sound when they are peeled off and why they can damage delicate surfaces, such as fabrics, when attached to them.

The team believes a 3D mushroom design can be made with softer, more flexible materials. The half-spherical mushroom shapes provide sufficient interlocking force on the fabric and hold strong.

For the study, the authors used 3D printing combined with molding to create soft surfaces patterned with the tiny mushrooms. That material was then safely attached to three different fabrics and removed without causing damage to them.

“We wanted to prove that, if you go toward these less stiff features, they can be used to attach and detach to soft and delicate surfaces, like fabrics, without damage. It can be used in many applications such as for diapers or silent fasteners for military use,” author Preeti Sharma said. “There is still a lot of research to be done, but the mushroom-shaped design worked quite well for soft mechanical fasteners.”

The design could lead to advances in the field of soft robotics. Soft robotics aims to build robots with designs that mimic living creatures like octopuses, caterpillars, and worms.

In that kind of robotics, interfaces play a significant role. With advances that make the current mushroom design stronger but keep its softness, it could be used to help robots walk on walls and ceilings like a gecko — an animal that can do that because of an attachment-detachment process that’s similar to how probabilistic fasteners work.

The design also could be used on grippers for robots used in farming and other agricultural jobs, Sharma said.

Sharma said more research into the design is needed before it is ready to be used in a commercially available product. Minor changes to the mushroom shape, possibly lengthening or shortening it to make it more effective, could lead to an even better product, she said.

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Materials provided by American Institute of Physics. Note: Content may be edited for style and length.

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