Reaching like an octopus: A biology-inspired model opens the door to soft robot control

Peer-Reviewed Publication

UNIVERSITY OF ILLINOIS GRAINGER COLLEGE OF ENGINEERING

 

IMAGE: SIMULATION OF AN OCTOPUS GRASPING A CYLINDER view more 

CREDIT: THE GRAINGER COLLEGE OF ENGINEERING AT UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN

Octopus arms coordinate nearly infinite degrees of freedom to perform complex movements such as reaching, grasping, fetching, crawling, and swimming. How these animals achieve such a wide range of activities remains a source of mystery, amazement, and inspiration. Part of the challenge comes from the intricate organization and biomechanics of the internal muscles.

This problem was tackled in a multidisciplinary project led by Prashant Mehta and Mattia Gazzola, professors of mechanical science & engineering at the University of Illinois Urbana-Champaign. As reported in Proceedings of the Royal Society A, the two researchers and their groups have developed a physiologically accurate model of octopus arm muscles. “Our model, the first of its kind, not only provides insight into the biological problem, but a framework for design and control of soft robots going forward,” Mehta said.

The impressive capabilities of octopus arms have long served as an inspiration for the design and control of soft robots. Such soft robots have the potential to perform complex tasks in unstructured environments while operating safely around humans, with applications ranging from agriculture to surgery.

Graduate student Heng-Sheng Chang, the study’s lead author, explained that soft-bodied systems like octopuses’ arms present a major modeling and control challenge. “They are driven by three major internal muscle groups—longitudinal, transverse, and oblique—that cause the arm to deform in several modes—shearing, extending, bending, and twisting,” he said. “This endows the soft muscular arms with significant freedom, unlike their rigid counterparts.”

The team’s key insight was to express the arm musculature using a stored energy function, a concept borrowed from the theory of continuum mechanics. Postdoctoral scholar and corresponding author Udit Halder explained that “The arm rests at the minimum of an energy landscape. Muscle actuations modify the stored energy function, thus shifting the equilibrium position of the arm and guiding the motion.”

Interpreting the muscles using stored energy dramatically simplifies the arm’s control design. In particular, the study outlines an energy-shaping control methodology to compute the necessary muscle activations for solving manipulation tasks such as reaching and grasping. When this approach was numerically demonstrated in the software environment Elastica, This model led to remarkably life-like motion when an octopus arm was simulated in three dimensions. Moreover, according to Halder, “Our work offers mathematical guarantees of performance that are often lacking in alternative approaches, including machine learning.”

“Our work is part of a larger ecosystem of ongoing collaborations at the University of Illinois,” Mehta said. “Upstream, there are biologists who perform experiments on octopuses. Downstream, there are roboticists who are taking these mathematical ideas and applying them to real soft robots.”

Mehta’s and Gazzola’s groups collaborated with Rhanor Gillette, Illinois Professor Emeritus of molecular and integrative physiology, to incorporate observed octopus physiology into their mathematical model for this study. Future work will discuss the biological implications of energy-based control. In addition, the researchers are collaborating with Girish Krishnan, an Illinois professor of industrial & enterprise systems engineering, to incorporate their mathematical ideas into real soft robot design and control. This will not only create a systematic way of controlling soft robots, but will also provide a deeper understanding of their working mechanisms.

This work was part of the CyberOctopus project, a multidisciplinary university research initiative in the University of Illinois’ Coordinated Science Laboratory supported by the Office of Naval Research.

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JOURNAL

Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences

DOI

10.6084/m9.figshare.c.6373262 

ARTICLE TITLE

Energy-shaping control of a muscular octopus arm moving in three dimensions

Simultaneous electricity generation and filteration of wastewater

A novel membrane using a combination of a water filteration membrane and conductive polymer, Water quality improvement and continuous electricity generation using a simple operation method

Peer-Reviewed Publication

NATIONAL RESEARCH COUNCIL OF SCIENCE & TECHNOLOGY

 

IMAGE: ELECTRICITY GENERATION AND WATER PURIFICATION MEMBRANE DEVELOPED BY THE KIST-MYONGJI UNIVERSITY JOINT RESEARCH TEAM view more 

CREDIT: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY

The purification of various water resources, such as rain, seawater, groundwater, river water, sewage, and wastewater, into potable or usable water is a high-energy process. So, what if electricity could be generated during the water purification process? In the spotlight, a domestic research team has developed a multifunctional membrane that can simultaneously generate electricity while purifying wastewater into drinking water.

The Korea Institute of Science and Technology (KIST, President Seok Jin Yoon) has announced that Dr. Ji-Soo Jang's team from the Electronic Materials Research Center and Prof. Tae-Gwang Yoon's team from the Department of Materials Science and Engineering, Myongji University (President Byeong-Jin Yoo) have jointly developed an advanced membrane that can simultaneously provide drinking water and generate continuous electricity from various water resources, such as sewage/wastewater, seawater, and groundwater.

The developed "sandwich-like" membrane is composed of a porous membrane that filters water at the bottom and a conductive polymer that generates electricity at the top. The membrane is designed to purify wastewater by controlling the direction of the water flow. Water flowing perpendicularly to the membrane generates direct current by the movement of ions along the horizontal direction. The membrane can reject more than 95% of the contaminants of sizes less than 10 nm (one hundred-millionth of a meter). Hence, microplastics and heavy metal particles in wastewater can be removed, and continuous electricity can be generated for more than 3 h with only 10 µl (microliter) of water.

Since the membrane can be manufactured using a simple printing process without size restrictions, it has a high potential to be commercialized due to low manufacturing costs and processing time. The research team is currently conducting follow-up research to generate electricity while improving the water quality of wastewater to the level of drinking water by developing the membrane for an actual factory. Dr. Ji-Soo Jang from KIST expressed his opinion on the research saying that, "As a novel technology that can solve water shortage problem and produce ecofriendly energy simultaneously, it also has great potential applications in the water quality management system and emergency power system."

Schematic illustration for the operation of the electricity generation and water purification membrane developed by KIST-Myongji University joint research team

CREDIT

Korea Institute of Science and Technology

This research was conducted as a major project of KIST with the support of the Ministry of Science and ICT (Minister Jong-Ho Lee). These research findings were published in the latest issue of Advanced Materials, an international journal of materials (IF: 32.086, top 2.17% in the JCR field), and were selected to be on the front cover of the issue.

KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr

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JOURNAL

Advanced Materials

DOI

10.1002/adma.202209076 

ARTICLE TITLE

Bidirectional water-stream behavior on multifunctional membrane for simultaneous energy generation and water purification

Shuttle Revolution by graduate indie games studio Head Empty wins Tranzfuser

Grant and Award Announcement

UNIVERSITY OF HUDDERSFIELD

 

IMAGE: GAMERS TRY OUT SHUTTLE REVOLUTION FOR THE TRANZFUSER SHOWCASE WHICH SAW A RETURN TO THE IN-PERSON CULMINATION OF THE COMPETITION AS 21 TEAMS TOOK TO THE FLOOR AT LONDON’S EXCEL ARENA AS PART OF THE UK’S BIGGEST CONSUMER-FACING GAMES SHOW, EGX. view more 

CREDIT: HEAD EMPTY STUDIOS

AN ACTION-PACKED computer game that takes the sport of badminton to a whole new level created by graduates at the University of Huddersfield has proved a smash-hit with the gaming community after coming top in a national games showcase competition.

Daniel Haynes, Harlow Grinney, May Thornborrow, and Shaun Kennie are company directors of Head Empty Studios which has been set up with the help of the University’s Enterprise Team. Their game titled Shuttle Revolution soared to success beating competitors from across the UK to become a winner of the latest Tranzfuser competition.  Their prize is a £20k grant from the UK Games Fund to continue the commercial development of their game.

Shuttle Revolution is described as ‘a stylist 2.5D badminton fighting game’.  Players can choose a character from a diverse cast of ten up-and-coming badminton champions, each with a unique twist to master that ranges from psychic energy manipulation and bionic grappling hooks to long-dormant ancient spirits with unfinished badminton business.

Through the streets of ‘Euron’ players can battle waves of AI on the badminton court travelling down branching story paths depending on what decisions they make after each victory, allowing for different endings per character.  Or they can take on formidable opponents in online battles to become the supreme Badminton champion.

Head Empty Co-director Daniel Haynes graduated with a First-Class Honours degree in Computer Science with Games Programming from the University in 2022.  He said the Tranzfuser competition has provided the team with a valuable ‘foot in the door’ to the game development industry and the motivation to explore careers as ‘indie devs’ from their own indie games studio.

He added the assistance of the University’s Enterprise Team was also invaluable and that he couldn’t imagine how difficult the process would have been to set up a business without their involvement, especially if like them, you’re entering the business world completely blind with no prior experience.

The University’s Enterprise Team educates and advises current students and graduates on all thing's enterprise and entrepreneurship. Their services include 1:1 business support, workshops to develop enterprise and employability skills, boot camps, access to the business incubation hub, grant funding and more.

“The provision of the 3M building to act as a correspondence address was also a really convenient feature that would otherwise be unavailable to those who can’t access an entire dedicated building for business. This was even more so for us due to the team being spread out all over the country and working primarily from home.,” he said.

Since launching in 2016, Tranzfuser has seen hundreds of passionate and talented graduate game developers take an idea for a game and make it into a playable reality. Many teams from the programme have gone on to achieve commercial success, whilst others have secured lucrative positions within the highly competitive games industry.

This year saw the return to the in-person culmination of the competition as 21 teams took to the floor at London’s ExCeL Arena as part of the UK’s biggest consumer-facing games show, EGX.  Each studio had their games played and tested by the enthusiastic game-playing public and were invited to deliver a pitch to the UK Games Fund during the event.

If the game is successful Daniel says the Studio plans to make another and support the previous one with paid content post-launch.

“Securing stable funding from a publisher or platform holder is now our next step to ensure we can continue with the company and game,” he added..

New study takes close look at energy storage

Researchers publish detailed analysis of prospects for the development of solid-state batteries / Review in Nature Energy

Reports and Proceedings

UNIVERSITY OF MÜNSTER

 

IMAGE: DOCTORAL STUDENT LAURA GOODWIN FROM JUSTUS LIEBIG UNIVERSITY GIESSEN WITH A SOLID-STATE CELL ON A LABORATORY SCALE. view more 

CREDIT: JLU/ROLF K. WEGST

Research into electrochemical energy storage devices and their development are among those fields of material sciences in which most work is being done worldwide. The rapidly growing need for high-performance batteries for a large number of applications has led to an increasing interest in achievable charging capacities and speeds. Equally, attention is being focused more strongly on the lifetimes, safety and availability of material resources, as well as on carbon footprints. It is against this background that chemists Prof. Jürgen Janek from Justus Liebig University Giessen and Prof. Wolfgang Zeier from the University of Münster and Helmholtz Institute Münster of Forschungszentrum Jülich (Germany), took a close look at the developments of the last ten years in the field of solid-state batteries. For this purpose, the researchers analysed the current state of the technology, critically considering the challenges and the unresolved issues which need to be dealt with to make solid-state batteries competitive. This critical assessment of the technology has been published in the latest issue of the journal Nature Energy as a review article.

The solid-state battery is a further development of the lithium-ion battery, whose function is currently achieved by means of a liquid, organic electrolyte. The aim is to use a solid electrolyte in solid-state batteries, promising better storage properties, longer lifetimes and increased safety. The development of solid-state batteries has been pursued worldwide in intensive research work for about ten years now.

“What is becoming clear is that the concept of the solid-state battery today comprises a number of variations, the success of which cannot be safely predicted yet,” is how Jürgen Janek summarises the state of play in developments. One conclusion the researchers have drawn is that, in spite of the wide-ranging activities being undertaken in research institutes and industrial companies, there is not yet measurable progress over the established lithium-ion technology with its liquid electrolytes. In their analysis they mention various aspects as representing decisive challenges. One key point is the development of solid electrolytes which can ensure higher battery performance and safety at the same time as having as low a concentration of lithium as possible. Moreover, a maximum-capacity anode material is required which enables the battery to have less volume and weight. Overall, the researchers say that new approaches in material research through a combination of theory and experiment are necessary, in particular through collaborations between as many different disciplines as possible. “We take an optimistic view,” says Wolfgang Zeier. “Without any doubt, solid-state batteries will reach the commercialisation stage. The question is just when, and to what extent.”

Back in 2016, Jürgen Janek and Wolfgang Zeier, who were both at the University of Giessen at that time, also analysed the prospects for solid-state batteries and published their results in Nature Energy. Since then, the article has been cited more than 2,000 times, having a decisive influence on this field of research. In their latest and more comprehensive article in the same journal, the two authors have updated their analysis. In this earlier analysis in 2016 there were many basic questions which were still unanswered and largely unresolved, but this time there are additional factors which play a role – on the one hand as a result of implementing the technology and, on the other, concerning the important questions of material resources and costs.

 

The authors

The authors are among the leading international scientists working in the field of physical-chemical and inorganic chemical material research. Since 1999, Prof. Jürgen Janek has headed a working group on solid-state electrochemistry at the University of Giessen. He is also head of the Centre for Materials Research there and is one of the two scientific directors of the BELLA laboratory at the Karlsruhe Institute of Technology. He is a member of the Leopoldina National Academy of Sciences and for his achievements he was recently awarded an honorary doctorate by the Technical University of Delft, as well as the Greve Prize, presented by the Leopoldina for the first time. Prof. Wolfgang Zeier is Professor of Inorganic Solid-State Chemistry at the University of Münster and is also head of the Design of Solid Ionic Conductors department at Helmholtz Institute Münster (HI MS; IEK-12) of Forschungszentrum Jülich. The work done by his group on solid ionic conductors and solid-state batteries has received many awards – including, recently, one from the International Battery Association.

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JOURNAL

Nature Energy

DOI

10.1038/s41560-023-01208-9 

METHOD OF RESEARCH

Systematic review

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Challenges in speeding up solid-state battery development

ARTICLE PUBLICATION DATE

23-Feb-2023

Hypnosis, meditation, and prayer: which is most helpful for pain management?

The research study involved the participation of 232 healthy adults

Peer-Reviewed Publication

BIAL FOUNDATION

Researchers compared the immediate effects of hypnosis, mindfulness meditation, and Christian prayer on pain intensity and tolerance. The results suggested that a single session of hypnosis and mindfulness meditation, but not prayer, may be useful for managing acute pain, with hypnosis being slightly more useful.

Who never felt pain? Probably a tiny number of people. Pain is a common human experience, and its acute state can have negative impacts on several health domains, including sleep quality, cardiovascular and immune function, and psychological well-being.

In addition to being almost universal, pain is also a complex experience influenced by biological, psychological, and social factors. So adequate pain management requires more than biological treatments alone, such as analgesic medications.

There are then several approaches that focus on the biopsychosocial factors that influence pain, including psychosocial, complementary, and integrative approaches. Previous studies confirm the usefulness of hypnosis, mindfulness meditation, and prayer as useful practices in the self-management of chronic pain in adults. However, their effects on acute pain have been less investigated and there has not yet been any study that has compared the immediate effects of these three approaches on the experience of acute pain.

It was in this context that, with the support of the BIAL Foundation, the research team led by Alexandra Ferreira-Valente resorted to the heart rate variability and other measures to compare the immediate effects of hypnosis, mindfulness meditation, and Christian prayer on pain intensity, pain tolerance, and stress. The results of the study are described in the article “Immediate Effects of Hypnosis, Mindfulness Meditation, and Prayer on Cold Pressor Outcomes: A Four-Arm Parallel Experimental Study”, published in the Journal of Pain Research in December 2022.

The study took place at the facilities of the Psychology Laboratory of the William James Center for Research at Ispa – Instituto Universitário in Lisbon, involving the participation of 232 healthy adults. Pain was induced in the participants by wrapping the forearm and hand in a cold compress (Cold Pressor Arm Wrap - CPAW) for up to 5 minutes at the most and assessing their pain tolerance, the intensity of pain, as well as heart rate variability, as a physiological marker of stress. After a rest period, participants listened to a 20-minute recording of guided hypnosis, or mindfulness meditation, or suggesting a Christian prayer, or reading a natural history book (control condition) depending on the group they were randomly assigned to. After this session, the participants underwent a second session of CPAW, during which they listened to up to 5 minutes of the recording and their cardiac function was monitored.

The results obtained by researchers from the William James Center for Research – Ispa (Portugal), Universidade Católica Portuguesa (Portugal), University of Washington (USA), Young Harris College (USA), and University of Queensland (Australia) suggest that single brief session of hypnosis and mindfulness meditation, but not Ignatian Christian prayer based on biblical meditation, may be useful for acute pain self-management, with hypnosis being the slightly superior option.

According to Alexandra Ferreira-Valente, team coordinator, “in the future, researchers should compare the effects of different types of prayer and examine the predictors and moderators of the effects of hypnosis and mindfulness on the experience of acute pain”.

Learn more about the project “188/18 - COping with PAin through Hypnosis, mindfulness and Spirituality (COPAHS)” here.

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JOURNAL

Journal of Pain Research

DOI

10.2147/JPR.S388082 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Immediate Effects of Hypnosis, Mindfulness Meditation, and Prayer on Cold Pressor Outcomes: A Four-Arm Parallel Experimental Study

Tracking how magnetism affects animal behavior

We still know little about how animal behaviour changes in response to magnetic fields. A new review provides a tutorial introduction to the study of this fascinating and potentially useful phenomenon.

Reports and Proceedings

SPRINGER

For over 50 years, scientists have observed that the behaviour of a wide variety of animals can be influenced by the Earth’s magnetic field. However, despite decades of research, the exact nature of this ‘magnetic sense’ remains elusive. Will Schneider and Richard Holland from Bangor University in Wales and their co-worker Oliver Lindecke from the Institute for Biology, Oldenburg, Germany have now written a comprehensive overview of this cross-disciplinary field, with an emphasis on the methodology involved. This work is now published in the journal EPJ Special Topics.

This magnetic sense, or ‘magnetoreception’, was first noticed in birds, and particularly in migratory songbirds. It has now been observed in many other species including mammals, fish and insects. However, the exact relationship between the magnetic field and the behaviour is difficult to pin down because it can be masked by other environmental factors. Experiments must be very carefully designed if their results are to be statistically sound.

“We aim to provide a balanced overview for researchers who wish to enter this exciting area of sensory biology,” explains Schneider. He and his co-authors outlined a range of methods that are used to deduce whether an animal’s behaviour is affected by a magnetic field. These include using GPS to mark animals’ alignment with the Earth’s field during normal activities, such as cows grazing; observing behaviour after tissues thought to be responsible for magnetoreception have been removed, or genes knocked out; and attaching small magnets on or near the animals’ bodies to disrupt the mechanism. Further work by animal physiologists, neuroscientists, geneticists and others will also be necessary to truly understand this phenomenon.

And this research is not only of academic interest. “Understanding animal magnetoreception will help us to protect animals released into unknown environments in the wild,” adds Lindecke.

###

Reference:

Schneider, W.T., Holland, R.A. & Lindecke, O. Over 50 years of behavioural evidence on the magnetic sense in animals: what has been learnt and how? Eur. Phys. J. Spec. Top. (2023). https://doi.org/10.1140/epjs/s11734-022-00755-8

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JOURNAL

The European Physical Journal Special Topics

DOI

10.1140/epjs/s11734-022-00755-8 

ARTICLE TITLE

Over 50 years of behavioural evidence on the magnetic sense in animals: what has been learnt and how?

China should be a global leader in addressing climate change, with both the government and individuals being responsible for taking action, say over 3,700 Chinese adults in two surveys

Peer-Reviewed Publication

PLOS

China should be a global leader in addressing climate change, with both the government and individuals being responsible for taking action, say over 3,700 Chinese adults in two surveys.

####

Article URL: https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0000065

Article Title: Public opinion on climate change in China—Evidence from two national surveys

Author Countries: Taiwan

Funding: The Author J.L. is supported by the China Energy Policy Postdoctoral Fellowship at the Ash Center for Democratic Innovation and Governance at Harvard Kennedy School and Taiwan’s National Science and Technology Council (NSTC) grant 109-2410-H-002-007-MY3. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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JOURNAL

PLOS Climate

DOI

10.1371/journal.pclm.0000065 

ARTICLE TITLE

Public opinion on climate change in China—Evidence from two national surveys

Making an electrically conducting soft polymer in a living tissue

Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

Researchers have developed a way to make bioelectronics directly inside living tissues, an approach they tested by making electrodes in the brain, heart, and fin tissue of living zebrafish, as well as in isolated mammalian muscle tissues. According to the authors, the new method paves the way for in vivo fabrication of fully integrated electronic circuits within the nervous system and other living tissue. “Safety and stability analyses over long periods will be essential to determining whether such technology is useful for chronic implantations,” writes Sahika Inal in a related Perspective. “However, the strategy … suggests that any living tissue can turn into electronic matter and brings the field closer to generating seamless biotic-abiotic interfaces with a potentially long lifetime and minimum harm to tissues.” Implantable electronic devices that can interface with soft biological neural tissues offer a valuable approach to studying the complex electrical signaling of the nervous system and enable the therapeutic modulation of neural circuitry to prevent or treat various diseases and disorders. However, conventional bioelectronic implants often require the use of rigid electronic substrates that are incompatible with delicate living tissues and can provoke injury and inflammation that can affect a device’s electrical properties and long-term performance. Overcoming the incompatibility between static, solid-state electronic materials and dynamic, soft biological tissues has proven challenging. Here, Xenofon Strakosas and colleagues present a method to fabricate polymer-based, substrate-free electronic conducting materials directly inside a tissue. Strakosas et al. developed a complex molecular precursor cocktail that, when injected into a tissue, uses endogenous metabolites (glucose and lactate) to induce polymerization of organic precursors to form conducting polymer gels. To demonstrate the approach, the authors “grew” gel electrodes in the brain, heart, and fin tissue of living zebrafish, with no signs of tissue damage, and in isolated mammalian muscle tissues, including beef, pork and chicken. In medicinal leeches, they showed how the conducting gel could interface nervous tissue with electrodes on a tiny flexible probe.

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JOURNAL

Science

DOI

10.1126/science.adc9998 

ARTICLE TITLE

Metabolite-induced in vivo fabrication of substrate-free organic bioelectronics

ARTICLE PUBLICATION DATE

24-Feb-2023

Electrodes grown in the brain – paving the way for future therapies for neurological disorders

Metabolite-induced in vivo fabrication of substrate-free organic bioelectronics

Peer-Reviewed Publication

LINKÖPING UNIVERSITY

 

IMAGE: THE INJECTABLE GEL BEING TESTED ON A MICROFABRICATED CIRCUIT. view more 

CREDIT: THOR BALKHED

The boundaries between biology and technology are becoming blurred. Researchers at Linköping, Lund, and Gothenburg universities in Sweden have successfully grown electrodes in living tissue using the body’s molecules as triggers. The result, published in the journal Science, paves the way for the formation of fully integrated electronic circuits in living organisms.

“For several decades, we have tried to create electronics that mimic biology. Now we let biology create the electronics for us,” says Professor Magnus Berggren at the Laboratory for Organic Electronics, LOE, at Linköping University. 

Linking electronics to biological tissue is important to understand complex biological functions, combat diseases in the brain, and develop future interfaces between man and machine. However, conventional bioelectronics, developed in parallel with the semiconductor industry, have a fixed and static design that is difficult, if not impossible, to combine with living biological signal systems.

To bridge this gap between biology and technology, researchers have developed a method for creating soft, substrate-free, electronically conductive materials in living tissue. By injecting a gel containing enzymes as the “assembly molecules”, the researchers were able to grow electrodes in the tissue of zebrafish and medicinal leeches.

“Contact with the body’s substances changes the structure of the gel and makes it electrically conductive, which it isn’t before injection. Depending on the tissue, we can also adjust the composition of the gel to get the electrical process going,” says Xenofon Strakosas, researcher at LOE and Lund University and one of the study's main authors.

The body’s endogenous molecules are enough to trigger the formation of electrodes. There is no need for genetic modification or external signals, such as light or electrical energy, which has been necessary in previous experiments. The Swedish researchers are the first in the world to succeed in this.

Their study paves the way for a new paradigm in bioelectronics. Where it previously took implanted physical objects to start electronic processes in the body, injection of a viscous gel will be enough in the future.

In their study, the researchers further show that the method can target the electronically conducting material to specific biological substructures and thereby create suitable interfaces for nerve stimulation. In the long term, the fabrication of fully integrated electronic circuits in living organisms may be possible.

In experiments conducted at Lund University, the team successfully achieved electrode formation in the brain, heart, and tail fins of zebrafish and around the nervous tissue of medicinal leeches. The animals were not harmed by the injected gel and were otherwise not affected by the electrode formation. One of the many challenges in these trials was to take the animals’ immune system into account.

“By making smart changes to the chemistry, we were able to develop electrodes that were accepted by the brain tissue and immune system. The zebrafish is an excellent model for the study of organic electrodes in brains,” says Professor Roger Olsson at the Medical Faculty at Lund University, who also has a chemistry laboratory at the University of Gothenburg.

It was Professor Roger Olsson who took the initiative for the study, after he read about the electronic rose developed by researchers at Linköping University in 2015. One research problem, and an important difference between plants and animals, was the difference in cell structure. Whereas plants have rigid cell walls which allow for the formation of electrodes, animal cells are more like a soft mass. Creating a gel with enough structure and the right combination of substances to form electrodes in such surroundings was a challenge that took many years to solve.

“Our results open up for completely new ways of thinking about biology and electronics. We still have a range of problems to solve, but this study is a good starting point for future research,” says Hanne Biesmans, PhD student at LOE and one of the main authors.

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JOURNAL

Science

DOI

10.1126/science.adc9998 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Metabolite-induced in vivo fabrication of substrate-free organic bioelectronics

ARTICLE PUBLICATION DATE

23-Feb-2023

Massive fossil analysis reveals variable

impact of end-Cretaceous extinction on

sharks, skates and rays

Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

A massive trove of global fossil data has revealed variations in how elasmobranch species – sharks, skates, and rays – recovered after the Cretaceous-Paleogene (K-Pg) mass extinction event. Among the findings, species with restricted geographic ranges, as well as old shark species, show higher extinction rates. Understanding how elasmobranch species responded to past mass extinctions helps researchers identify the features of extinction victims and of extinction survivors. The Cretaceous-Paleogene (K-Pg) mass extinction event, which occurred roughly 66 million years ago, was Earth’s last major extinction event and is estimated to have resulted in the removal of 55 to 76% of the planet’s species. While the event drove drastic ecological changes in ecosystems worldwide, recent studies have suggested that the extinction patterns across the K-Pg boundary were complex and varied in severity between clades, ecologies, and geographical areas. However, studies involving extinction patterns among marine vertebrates are rare, meaning the end-Cretaceous extinction’s impact on marine vertebrate diversity remains largely uncharacterized. To address this gap, Guillaume Guinot and Fabien Condamine compiled a global database of elasmobranch fossils representing 675 sharks, skate, and ray species spanning the Late Cretaceous-Paleogene interval. Their analysis revealed a significant loss of diversity following the K-Pg extinction; overall, elasmobranch species declined by more than 62% and did not fully recover in the Paleocene. However, the patterns of this extinction varied. According to the findings, rays and species that fed on shelled prey (durophagous), as well as more ancient shark species, reached the highest levels of extinction (more than 72%). Other sharks and nondurophagous species fared better and experienced a more rapid recovery following the extinction. Moreover, pelagic species with large geographic ranges and those restricted to higher latitudes also showed greater survival across the K-Pg boundary.

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JOURNAL

Science

DOI

10.1126/science.abn2080 

ARTICLE TITLE

Global impact and selectivity of the Cretaceous-Paleogene mass extinction among sharks, skates, and rays

ARTICLE PUBLICATION DATE

24-Feb-2023

*Free* Revealed: The precarious state of “Extinct in the Wild” species

Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

Extinct in the Wild (EW) species are regarded as facing the highest risk of extinction under the International Union for Conservation of Nature (ICUN) Red List of Threatened Species (Red List). However, because EW species are not subject to the same detailed assessments directed toward species that remain in the wild, the extent and variation of this risk are poorly understood. In this Review, Donal Smith and colleagues synthesize data on EW plant and animal species to provide a comprehensive report on their perilous state and conservation history. “The cases we depict chart more than 70 years of attempts to use ex situ conservation to prevent extinction and facilitate the recovery of species on the very brink, highlighting both the fragility of this status and the potential for success despite that fragility,” write Smith et al. EW species – those known only to exist in zoos, aquariums, gardens or seed banks – are considered to be at the highest risk of extinction. Despite this, they occupy an overlooked space on the ICUN Red List framework for evaluating and comparing species’ risk of extinction because the Red List process generally focuses only on wild populations. Here, Smith et al. provide assessments for 84 EW species (40 animals and 44 plants) that summarize their state of risk, their current ex situ populations and the conservation actions being taken to recover them. The findings highlight that most EW populations are small – often fewer than 1000 individuals – with low genetic diversity due to a limited number of population founders. Moreover, most EW plant species depend on live propagation by a small number of holders. Fewer still are secured at seed banks. And, while reestablishment of species in the wild has shown success for some EW species, attempts to do so are rare. In total, Smith et al. argue that the state of EW species should be regarded with a sense of urgency and that an improved system of evaluating and managing EW populations is crucially needed to prevent extinctions.

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JOURNAL

Science

DOI

10.1126/science.add2889 

ARTICLE TITLE

Extinct in the wild: the precarious state of Earth's most threatened group of species

ARTICLE PUBLICATION DATE

24-Feb-2023