Exploring prediction errors that can influence human perceptions of time

by Ingrid Fadelli , Medical Xpress
  

Image showing activation in the Basal Ganglia. In the highlighted location, brain activation is opposite for positive and negative prediction errors in correct/incorrect time perception. The researchers suggest that the bias in time perception due to the presence of prediction errors might have originated from the interaction between time and PE in this brain region. Credit: Toren, Aberg & Paz.

Humans can sometimes perceive the passing of time differently, for instance, feeling as though an hour passed very quickly or that a few minutes went by extremely slowly. This suggests that the human perception of time is subjective and can be affected by many factors that can cause people to perceive the same amount of time as longer or shorter than it actually is.

Researchers at the Weizmann Institute of Science in Israel have recently carried out a fascinating study exploring if and how prediction errors can bias how different individuals perceive the passing of time. Their paper, published in Nature Neuroscience, shows that time perception can be influenced by both positive and negative prediction errors, while also identifying the putamen as a brain region responsible for biased time perception.

"Our lab studies, among other things, the process of learning from errors (reinforcement learning)," Rony Paz, head of the lab that carried out the study, told MedicalXpress. "Dopaminergic brain activation in a structure called the basal ganglia (BG) is known to be related to reinforcement learning in general, and reward prediction errors processing in particular. BG activation is also related to time perception required for motor functions that our brain controls."

For many years, time perception and human prediction errors were seen as almost entirely independent processes. The study by Paz and his colleagues challenges this idea, suggesting that these two elements are, in fact, deeply interlinked.

"Time perception and prediction error computation have often been considered to be mostly independent processes," Paz said. "The core idea of our study was to challenge this notion. Since the perception of time is subjective and was shown to be biased by many factors, and since both functions are processed in the same brain circuits, the two might interact and either aid or interfere with each other."
  

The main behavioral result collected by the researchers (i.e., how participants estimated time in different conditions). Higher location in the plot indicates higher error-rate in time perception. The orange line shows time perception when outcome is expected, while red/blue lines are time perception during PE-/PE+ respectively. It can be seen that time perception is biased for both PE-/PE+ (compared to expectation PE0) but in opposite directions. Credit: Toren, Aberg & Paz.

The key objective of the recent work by Paz and his colleagues was to investigate whether time perception is influenced by prediction errors, and if it is, to identify the neural underpinnings of this process. To achieve this, the researchers designed a behavioral task executed inside an fMRI scanner, in which participants are presented with different pairs of images on a screen, displayed for various amounts of time.


During each trial, the group of participants they recruited were asked to decide which of two images they saw on the screen was displayed for the longer amount of time. The images were overlaid with numbers that represented monetary gains and losses, as these would lead to predictions and errors.

"This design allowed us to measure time perception with a wide range of time differences, and importantly, in the presence of predicted vs. unpredicted outcomes," Paz explained. "The use of monetary gains and losses offers the possibility to differentiate between positive prediction errors (i.e., getting more than you expect) and negative prediction errors (i.e., getting less than you expect)."

As those who took part in their experiment were inside an fMRI scanner, the researchers were able to collect brain imaging data that could shed some light on the neural underpinnings of biased time perception. They then used computational modeling approaches to analyze the data they collected and investigate brain activation in the presence of positive or negative prediction errors. These analyses yielded a number of interesting results, highlighting the link between time perception and positive/negative prediction errors and identifying the putamen (located within the BG) as the brain region responsible for this interaction.

"Firstly, we found that prediction errors do indeed bias time perception, which was not known before," Paz said. "Moreover, we were able to identify the characteristics of this cognitive bias: Time is overestimated when positive errors occur (i.e., when a user receives more than he expected) and is underestimated when negative errors occur. The observation that two different functions processed in the same brain circuits can interact might have implications on many other processes executed in similar brain circuits."

Paz and his colleagues are among the first to provide evidence of the interaction between time perception and human prediction errors, while also identifying the brain region where this interaction 'takes place' (i.e., the putamen). The results they gathered could serve as a basis for other studies exploring the neural underpinnings of time perception biases. In addition, this study could shed light on the complexities and neural dynamics of diseases associated with dysfunctions of the BG, such as Parkinson's disease (PD), which affects people's ability to learn and accurately perceive the passing of time.


Explore further Why visual perception is a decision process

More information: Ido Toren et al. Prediction errors bidirectionally bias time perception, Nature Neuroscience (2020). DOI: 10.1038/s41593-020-0698-3
Journal information: Nature Neuroscience

Researchers probe how aggression leads to more aggression

by Lori Dajose, California Institute of Technology
 

Credit: Pixabay/CC0 Public Domain

Like a champion fighter gaining confidence after each win, a male mouse that prevails in several successive aggressive encounters against other male mice will become even more aggressive in future encounters, attacking faster and for longer and ignoring submission signals from his opponent.


This phenomenon is interesting to people who study the neuroscience of behavior, because aggression is an innate, hard-wired behavior in the brain. This means that a mouse does not need to learn aggressive behaviors before it engages in them; aggression is instinctive upon reaching adulthood. However, experiences (say, repeated successful aggressive encounters) are able to alter this innate behavior.

Now, a team of Caltech researchers has discovered that hard-wired neural circuits governing aggression in mice are strengthened following their victories in aggressive encounters, and has identified a learning mechanism operating in the hypothalamus—a brain region traditionally viewed as the source of instincts, rather than learning.

The research was conducted in the laboratory of David Anderson, Seymour Benzer Professor of Biology, Tianqiao and Chrissy Chen Institute for Neuroscience Leadership Chair, Howard Hughes Medical Institute Investigator, and director of the Tianqiao and Chrissy Chen Institute for Neuroscience at Caltech.

A paper describing the research appears in the journal Proceedings of the National Academy of Sciences on September 24.

There is a difference between innate behaviors and those that are learned. For example, mice can be taught that performing certain behaviors (for example, pulling a lever) can result in a positive outcome (such as receiving food). On the other hand, innate behaviors like aggression are instinctive to male mice; the mice do not need to learn how to lunge and attack when confronted with other mice they deem a threat—they just react.

Previous studies have shown that a male mouse, once it has won in several aggressive encounters with other males, will exhibit increased aggression in future encounters. In other words, an innate behavior is altered by experience. This effect is termed "aggression training."


Led by postdoctoral scholar Stefanos Stagkourakis, the Caltech team examined a particular connection in the mouse brain where a group of synapses transfer signals from a little-studied region at the junction between the amygdala (a brain region notable for its role in fear-related behaviors) and the hippocampus (which plays a role in short-term memory) to a specific subdivision of the hypothalamus called the ventromedial hypothalamus (VMH), which controls aggressive behaviors in mice. (The hypothalamus also contains neurons in other subdivisions that mediate other social and homeostatic behaviors, such as mating, parental behavior, feeding, and thermoregulation, but these were not studied.)

The team found that after aggression training, these synapses show signs of long-term potentiation (LTP), which is similar to turning the volume knob up on the signal. Instead of just talking to the neurons in the hypothalamus, these synapses are shouting at them, causing them to react more strongly.

Using the Caltech Brain Imaging Center, the team studied the dendrites of neurons, protrusions extending from neurons that receive signals from other neurons, and in particular the dendrites' spines, structures that act like miniature radio antennae on the hypothalamic neurons to detect input from other brain regions. They examined the number, size, and shape of these structures before and after aggression training. They found that aggression training caused the growth of many additional dendritic spines on hypothalamic neurons. Such structural changes are expected to make these neurons more sensitive to incoming signals, and therefore more easily activated.

The team also experimentally prevented LTP from forming on these synapses during aggression training, and found that aggression-training no longer led to an increase in aggressive behaviors in these mice.

Although all of the male mice tested were genetically identical, about 25 percent never showed aggression and also were "immune" to the behavioral changes caused by aggression training. The authors further found that such behavioral heterogeneity among genetically identical mice is due to naturally occurring variations in serum testosterone levels: the non-aggressive mice had, on average, lower levels of testosterone than their aggressive siblings. Administration of supplemental testosterone to the non-aggressive mice caused both the appearance of aggressive behavior and LTP at the amygdala-hypothalamic synapses.

This work identifies changes in a very specific brain region after aggression training, but the adaptations that mediate the behavioral effect of aggression training likely occur at multiple sites in the brain. In future work, the team will examine how neural activity in different brain areas changes following social experience and will attempt to identify brain nodes of high significance in the neural circuit of aggression. The team also hopes to investigate how testosterone levels can vary among otherwise genetically identical mice, since the hormone is synthesized by genetically encoded enzymes.

The paper is titled "Experience-dependent plasticity in an innate social behavior is mediated by hypothalamic LTP."


Explore further

Neural circuit for detecting male pheromone cues relevant to inter-male aggression
More information: Stefanos Stagkourakis et al. Experience-dependent plasticity in an innate social behavior is mediated by hypothalamic LTP, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2011782117

Journal information: Proceedings of the National Academy of Sciences


Provided by California Institute of Technology

Songbirds sing, like humans flock, for opioid reward

by University of Wisconsin-Madison

Dosed with the opioid fentanyl, swallows like these would “sing like crazy” — but fall silent when researchers switched off their brains’ opioid receptors. Credit: Lauren Riters

What do songbirds and humans have in common? We crave social interaction, and the chemical rewards that flood our brain when we get it.

In a study recently published in Scientific Reports, University of Wisconsin–Madison researchers led by Lauren Riters, professor of integrative biology, found that when songbirds sing during non-mating seasons, it's because singing releases an opioid naturally produced in their brain —that's right, a compound with the same biological makeup of the highly addictive painkillers.

People have naturally-produced—or endogenous—opioids in our brain released in certain situations, like social situations, that make us feel good. That's why we like hanging out with friends, Riters says.

These naturally produced, feel-good compounds are also why many songbirds like to sing in large flocks, says Riters, after years of careful study.

"Animals—including birds, including humans—we produce our own endogenous opioids, and they reward behaviors naturally, like sexual behavior or feeding behavior," Riters says. "Studies show that endogenous opioids also make play rewarding. Songbirds learn their songs, and must practice. When we listened to birds practicing in flocks, it almost sounded as if they were playing around with the notes. Darwin even suggested that birds in flocks may be singing for 'their own amusement.' So, we thought if singing is a playful behavior, it should involve opioids."

About six years ago, a researcher in Riters' lab found a way to reduce the resonse of the Mu opioid receptors in European Starlings, a type of songbird. This receptor, a protein on the surface of a nerve cell, controls responses to endogenous opioids, and they wanted to figure out if it might regulate what sounded like playful song in birds.

To put this to the test, they had to develop a method in starlings to measure reward associated with singing. Riters' team used a method called CPP, a conditioned place preference test, where they trained the birds to associate a certain cage with singing. Later, when given a choice between two cages, birds showed a preference for the cage that they learned to associate with their own singing behavior. This shows that birds think of singing in flocks as a positive experience, Riters says.


"How do you ask a bird if it's feeling good?" Riters says. "This method is really important to studies that we've been running. It comes from studies in psychology, and is commonly used to study reward associated with drug use. We adapted it to ask questions about reward associated with singing behavior."

Once they could recognize what the birds looked like in the reward state, they administered tiny doses of fentanyl, a type of opioid that also binds to the Mu receptor, and found the drug made the birds "sing like crazy." Then they reduced the response of the opioid receptors and found that starlings no longer showed a CPP for song. This shows, Riters says, that endogenous opioids regulate intrinsically-rewarding bird song.

Riters' team ran tests over 2 years. They set up the experiment in an outdoor aviary where they'd observe the birds. Sometimes, Riters says, it proved challenging, since so many other factors contributed to the birds singing or not. Riters says her team had to make the environment as welcoming and relaxing as possible for the birds. For example, if a hawk landed near the aviary, the songbirds wouldn't sing because they'd get stressed out.

The results stood out amongst other research, because most studies of starling song involve the mating season and sexual selection, while the new study focused on song outside the breeding season in large flocks, and its connection with endogenous opioids.

"In terms of communication, not that many people are looking at the rewarding aspects, but definitely people are looking at dopamine, and how that regulates the motivation to communicate," Riters says. "Dopamine is something that, in humans, motivates your behavior and directs it towards reward."

She says her results might suggest that, in starlings, endogenous opioid-prompted song is evolutionarily advantageous, because singing in flocks allows them an opportunity to practice their song to prepare for the mating season. It might not be the most beautiful to listen to—Riters likened their chaotic song to freeform jazz—but that's okay. To them, it's just a warm-up for when they start looking for a mate.

"When the birds are singing they're also practicing motor patterns that they will later use in more serious adult contexts," Riters says. "They're also learning how to produce a vocalization that gets a social response, and they also learn how to attract a female, for example."

Riters thinks the release of opioids might also encourage sociable behavior for these songbirds. Humans have endogenous opioids that do just that, and Riters' research may also have implications for human sociality and even mental health. When humans interact in a social context, like hanging out with friends, their brains also release endogenous opioids, just like the songbirds.

Riters believes birds and mammals share the common ancestor in which these social rewards evolved, so there's a chance parts of their work can be generalized to humans.

In this case, the importance of sociality to both humans and songbirds cannot be understated. When humans don't receive enough social interaction, they might become depressed or experience other negative mental health conditions because their brains aren't producing those endogenous chemicals anymore. For example, people with social anxiety might not want to hang out in social groups, because they might have negative interactions. By studying birds, Riters says, maybe they can find ways to promote positive social interactions.

"We think that studying this kind of gregarious positive social play in songbirds is providing a unique way to come up with new ideas for treatments that might promote positive interactions in humans," Riters says. "During this pandemic and social distancing, we are missing our flockmates, right? And without contact with our flockmates, without socializing in our groups, I think we're really deprived of opioid release."


Explore further

Researchers ID chemical that influences songbirds' song choice
More information: Sharon A. Stevenson et al. Endogenous opioids facilitate intrinsically-rewarded birdsong, Scientific Reports (2020).

DOI: 10.1038/s41598-020-67684-1

Journal information: Scientific Reports


Provided by University of Wisconsin-Madison

New type of plastic made from reclaimed waste

by Claudia Engel, Fraunhofer-Gesellschaft

Compounded and granulated polyhydroxybutyrate (PHB). Credit: Fraunhofer-Gesellschaft

A new type of plastic made of reclaimed waste readily degrades in less than a year. The substance that will soon serve to manufacture and break down mainly disposable products in an ecofriendly way goes by the name of polyhydroxybutyrate. This innovative material can be produced on an industrial scale in a new process developed by the Fraunhofer Institute for Production Systems and Design Technology IPK and its partners.


Everyday life devoid of plastics—that would be hard to imagine. They figure prominently in packaging and consumer goods, and are indispensable to industry applications such as automotive and medical engineering. Reuse and recycling of plastics from fossil resources is hardly common practice. On top of that, they degrade at a glacial pace and pollute the environment for a long time to come. The great patches of plastic waste floating on our oceans attest to their power to pollute. Plastic bottles and bags despoil beaches and, in many places, entire stretches of land.

The Bioeconomy International research initiative

The need for global recycling strategies is urgent, given plastics' heavy use all over the world. More and more governments are resorting to bans to curb the swelling tide of plastic waste. A viable option to replace fossil-based plastics on a large scale has yet to be found. This is why the German Federal Ministry of Education and Research (BMBF) launched the "Bioökonomie International" (Bioeconomy International) research initiative in close cooperation with Fraunhofer IPK, the Department of Bioprocess Technology of the Technical University of Berlin, regional industrial partners and international research partners from Malaysia, Columbia and the U.S.. These researchers are developing a method of manufacturing polymers without drawing on premium resources such as mineral, palm and rapeseed oils, the production of which is very detrimental to the environment.

The Fraunhofer IPK team developed this injection molding tool to replicate prototype components made of polyhydroxybutyrate. Credit: Fraunhofer-Gesellschaft

A new plastic much like polypropylene

This new process turn industrial leftovers such as waste fats that contain a lot of mineral residue into polyhydroxybutyrate (PHB). Microorganisms can metabolize these residues in special fermentation processes. They deposit the PHB in their cells to store energy. "Once the plastic has been dissolved from the cell, it is still not ready for industrial use, because the hardening process takes far too long," says Christoph Hein, head of the Microproduction Technology department at Fraunhofer IPK. The raw material has to be mixed with chemical additives downstream in post-production stages. For example, the research team adjusted the plasticizing and processing parameters to trim the recrystallization time to fit the timing of industrial processing. The resultung biopolymer's properties resemble those of polypropylene. But unlike PP, this plastic degrades fully in six to twelve months.


In this method of producing plastic, microorganisms synthesize the entire polymer in a biotechnical process. "To this end, we convert biogenic residues such as waste fats into polyesters that can be put to technical use," says Hein. The researcher and his team opted for microorganisms, genetically modified with molecular methods, to serve as biocatalysts. With the help of chemical purification processes and an extensively optimized material, they have been able to develop a novel family of materials that satisfy the demands of technical plastics.

No petroleum-based synthetic components needed

The new process not only dispenses with petroleum-based synthetic components altogether; it also enables green plastic alternatives. Naturally occurring microorganisms can break down these newly developed plastics, so they need not be subjected to the special conditions that serve to degrade matter in industrial composting plants. They offer an ecofriendly alternative to making and degrading single-use products and other disposable items.

The process also lends itself to producing high-quality plastic parts for certain technical applications and periods of use. The specifications for this sort of product are more demanding. They may have to exhibit specific geometric tolerances and surface qualities or be reproducible with great precision. The researchers developed highly specialized replication processes to meet these requirements.

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Provided by Fraunhofer-Gesellschaft

Transforming waste into bio-based chemicals

by Emily Scott, Lawrence Berkeley National Laboratory

Credit: Pixabay/CC0 Public Domain

Researchers at Berkeley Lab have transformed lignin, a waste product of the paper industry, into a precursor for a useful chemical with a wide range of potential applications.

Lignin is a complex material found in plant cell walls that is notoriously difficult to break down and turn into something useful. Typically, lignin is burned for energy, but scientists are focusing on ways to repurpose it.

In a recent study, researchers demonstrated their ability to convert lignin into a chemical compound that is a building block of bio-based ionic liquids. The research was a collaboration between the Advanced Biofuels and Bioproducts Process Development Unit, the Joint BioEnergy Institute (both established by the Department of Energy and based at Berkeley Lab), and the Queens University of Charlotte.

Ionic liquids are powerful solvents/catalysts used in many important industrial processes, including the production of sustainable biofuels and biopolymers. However, traditional ionic liquids are petroleum-based and costly. Bio-based ionic liquids made with lignin, an inexpensive organic waste product, would be cheaper and more environmentally friendly.

"This research brings us one step closer to creating bio-based ionic liquids," said Ning Sun, the study's co-corresponding author. "Now we just need to optimize and scale up the technology."

According to Sun, bio-based ionic liquids also have a broad range of potential uses outside of industry. "We now have the platform to synthesize bio-based ionic liquids with different structures that have different applications, such as antivirals," Sun said.

Explore further Making biodiesel with green solvents

More information: Shihong Liu et al. Statistical design of experiments for production and purification of vanillin and aminophenols from commercial lignin, Green Chemistry (2020). DOI: 10.1039/D0GC01234C

Journal information: Green Chemistry

Provided by Lawrence Berkeley National Laboratory

Bacteria fed on a customized diet produce biodegradable polymers for alternative packaging in the cosmetics industry

by Claudia Vorbeck, Fraunhofer-Gesellschaft

Freeze-dried bacteria (Cupriavidus necator) before cell disruption. Credit: Fraunhofer-Gesellschaft

Germany generates around 38 kilograms of plastic waste per capita each year. In a joint project with the University of Stuttgart and LCS Life Cycle Simulation, researchers from the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB and the Fraunhofer Institute for Process Engineering and Packaging IVV are now working to establish a holistic concept for the sustainable use of biologically degradable packaging materials in the cosmetics industry. The project is focusing on polyhydroxyalkanoates (PHAs), which have similar properties to conventional plastics but are produced from microorganisms and without the use of fossil-based raw materials.


To date, the bacteria in Dr. Susanne Zibek's lab at Fraunhofer IGB in Stuttgart have been fed on a whole variety of waste materials, ranging from wood waste and oil and sugar residues to glycerol from biodiesel production. Each of these carbon-based feed sources causes the bacteria to produce specific intracellular storage granules. These so-called polyhydroxyalkanoates (PHAs) are the focus of SusPackaging, a research project that is being conducted in cooperation with Fraunhofer IVV in Freising, the University of Stuttgart and LCS Life Cycle Simulation, which is located in the town of Backnang. Researchers from Fraunhofer IGB are seeking to create biologically based, biodegradable polymers as a replacement for plastic packaging in the cosmetics industry. What sets the project apart is its attempt to establish a wholly green value chain. As Dr. Ana Lucía Vásquez-Caicedo from Fraunhofer IGB explains, a holistic concept with a focus on sustainability is new: "A lot of studies concentrate on individual aspects, but it's rare to see a consideration of the entire process chain all the way up to an evaluation of the quality of materials."

The process begins with cultivation of the bacteria. Dr. Susanne Zibek, group manager of the Food Processing Technology Group, and her colleague Dr. Thomas Hahn are investigating how specific microorganisms can be used to produce different PHAs with different structures, and how the choice of feed influences their characteristics. "Basically, we're trying to create new structural variants, so that we can then see whether the polymer produced is suitable as a packaging material," Zibek explains. The working group has support from researchers at the University of Stuttgart, who are taking a closer look at various characteristics of the microorganisms, including the extent to which they can adapt to toxic substances that might be contained in the natural feed sources.

Replacing harmful solvents with pressure change technology

Before the PHAs can be processed and tested, they must first be extracted from the microorganisms. This is the specialist field of Vásquez-Caicedo, group manager of the Food Processing Technology Group at Fraunhofer IGB. As a rule, this so-called purification process uses solvents such as chloroform. However, as she explains, the aim is to move away from environmentally harmful solvents. Instead, she has developed a purely mechanical/physical method of cell disruption. Known as pressure change technology (PCT), this involves the addition of a process gas to the fermentation broth containing the microorganisms. The broth is then pressurized, with the result that the gas penetrates the cytoplasm of the cells. A rapid lowering of pressure in the broth destroys the cells and releases the PHA.

Lab equipment for cell disruption and extraction of functional materials at Fraunhofer IGB. Credit: Fraunhofer-Gesellschaft

Following purification, the PHA is sent in the form of a white powder to Fraunhofer IVV in Freising. Here, it is turned first into granules and then into a polymer film. Initial testing on small sheets of this polymer has examined material characteristics such as thermal stability, plasticity and various barrier properties—essential if future packaging is to provide cosmetic ingredients with, for example, effective protection against desiccation.


Dr. Cornelia Stramm from Fraunhofer IVV is happy with the results so far: "In terms of their mechanical properties, some PHA types are still proving somewhat difficult to process. We need to make a few adjustments there. But in terms of their barrier properties, PHAs show great potential compared to other biopolymers." At the end of each testing cycle, she sends the results back to Stuttgart along with recommendations for further action, and then the process begins again.

Based on this feedback from Fraunhofer IVV, Zibek's working group at Fraunhofer IGB has modified its feed strategy. The bacteria are now given an additional cosubstrate, which increases the PHA's valerate content, thereby making the end product more pliable.

Further enhancement with every feedback loop

While volumes are still very low and production takes a lot of time, the process is steadily improving with each feedback loop.

Once the various steps have been finalized, a life cycle analysis conducted by external project partner LCS Life Cycle Simulation will evaluate the energy efficiency and sustainability of the entire process in order to compare it with existing processes. All three researchers from Fraunhofer see big potential for PHAs. In the future, particularly for small items of disposable packaging, they could offer a genuine alternative to conventional petroleum-based plastics.


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Provided by Fraunhofer-Gesellschaft

New process turns paper manufacturing waste into valuable chemicals

by Ames Laboratory

Credit: Ames Laboratory

A group of researchers at the U.S. Department of Energy's Ames Laboratory has discovered a way to convert a common byproduct of the paper manufacturing process into valuable chemical precursors for making nylon. The process is much more environmentally friendly in terms of the solvent(s) used and the energy inputs than other methods and provides a useful alternative to burning waste products of pulping.

Kraft (from the German meaning strength) lignin is a major waste product of the paper industry, amounting to about 50 million tons annually. This waste lignin is typically burned for heat, however, that process also releases carbon dioxide into the environment.

Ames Laboratory researchers discovered that treating this lignin with aqueous sodium hydroxide at reasonable temperatures (200 °C) produces guaiacol. Guaiacol can then be converted into nylon precursors under even milder conditions using suitable catalysts—creating a new, viable two-step process for producing important chemicals from lignin.

"We found that Kraft lignin was depolymerized in dilute alkaline solution at relatively low temperature (200 °C) under an ambient nitrogen pressure environment," said Igor Slowing, Ames Laboratory scientist and lead investigator. "We were able to produce guaiacol with high selectivity (>80%) in a total monomer amount of 13% based on the lignin input.

The team used a series of techniques including a suite of advanced solution and solid state nuclear magnetic resonance (NMR) experiments, mass spectrometry and model reactions to determine that guaiacol was generated mainly through cleavage of β-O-4 bonds in the original lignin structure. Cleaving this type of bond often requires severe reaction conditions, which many times lead to undesirable side reactions that result in formation of intractable chars."

The Kraft lignin-derived guaiacol was then converted to the nylon precursor Ketone Alcohol or KA oil, using Ru/C catalyst under 1 bar H2. The use of low H2 pressure proved critical to ensure full selectivity to KA oil, without formation of the undesired methoxy-cyclohexanol byproduct. Importantly, the deactivation of the Ru/C catalyst observed in the direct treatment of lignin, was avoided in the two-step procedure.

"This two-step process provides a new option for lignin utilization in the production of high-demand value-added chemicals," said Slowing. "We envision this process as a low-energy path that leaves the remaining oligomers available for downstream processing into other chemical commodities in an integrated refinery for waste Kraft lignin."

The research has been detailed in the Royal Society of Chemistry's journal Green Chemistry, Two-step conversion of Kraft lignin to nylon precursors under mild conditions.

Explore further  Transforming waste into bio-based chemicals

More information: Hui Zhou et al. Two-step conversion of Kraft lignin to nylon precursors under mild conditions, Green Chemistry (2020). 

DOI: 10.1039/D0GC01220C

Journal information: Green Chemistry

Provided by Ames Laboratory

Doll play activates brain regions associated with empathy and social skills

by Cardiff University

Credit: Cardiff University

A team of researchers from Cardiff University has used neuroscience for the first time to explore the impact doll play has on children.

In an 18-month study, the team monitored the brain activity of 33 children, aged between four and eight, as they played with dolls.

They found that doll play activated parts of the brain that allow children to develop empathy and social information processing skills, even when they were playing alone. Furthermore, they saw far less activation of this part of the brain when the children played with tablet computers on their own.

The findings of the study are published today in the journal Frontiers in Human Neuroscience.

Lead author Dr. Sarah Gerson, a senior lecturer at Cardiff University's Center for Human Developmental Science, said: "This is a completely new finding. The fact that we saw the posterior superior temporal sulcus (pSTS) to be active in our study shows that playing with dolls is helping them rehearse some of the social skills they will need in later life. Because this brain region has been shown to play a similar role in supporting empathy and social processing across six continents, these findings are likely to be country agnostic."

Dr. Gerson and colleagues used an emerging neuroimaging technology—functional near-infrared spectroscopy (fNIRS) - to scan brain activity while the children moved freely around.

They found that the pSTS, a region of the brain associated with social information processing such as empathy, was activated even when children played with dolls on their own, regardless of gender.

"We use this area of the brain when we think about other people, especially when we think about another person's thoughts or feelings," said Dr. Gerson.

"Dolls encourage them to create their own little imaginary worlds, as opposed to say, problem-solving or building games. They encourage children to think about other people and how they might interact with each other."

The study, conducted with Mattel, the makers of Barbie, is the first time neuroimaging data has been used to highlight how the brain is activated during natural doll play. As such, the researchers say it is a step forward in developmental science's understanding of this type of play.

In the study the play was split into different sections so the Cardiff team could capture the brain activity relating to each kind of play separately—playing with the dolls on their own; playing with the dolls together with another person (a research assistant); playing with the tablet game on their own and playing with the tablet game along with another person (a research assistant).

The dolls used included a diverse range of Barbies and sets. Tablet play was carried out using games that allow children to engage with open and creative play (rather than a rule or goal-based games) to provide a similar play experience to doll play.

The study found that when children played alone with dolls, they showed the same levels of activation of the pSTS as they do when playing with others. When the children were left to play tablet games on their own there was far less activation of the pSTS, even though the games involved a considerable creative element.

The researchers say the study is the first step toward understanding the impact of doll play and further work is required to build on these initial findings. Dr. Gerson and the Cardiff University team, along with Mattel, have committed to further neuroscience studies in 2021.


Explore further

Child's play in the time of COVID: Screen games are still 'real' play

More information: Salim Hashmi et al. Exploring the Benefits of Doll Play Through Neuroscience, Frontiers in Human Neuroscience (2020). 

DOI: 10.3389/fnhum.2020.560176

Provided by Cardiff University

Electronic collars less effective than reward-based training, research finds

by Alistair Berry, University of Lincoln

Credit: Unsplash/CC0 Public Domain

Training dogs with electronic collars is no more effective than traditional training methods, according to new research.


Animal behavior researchers at the University of Lincoln conducted a study looking at the efficacy of training with electronic or "E-collars," which deliver a small electric shock to dissuade unwanted behavior, such as ignoring commands.

Researchers analyzed video footage of training sessions where "come" and "sit" commands were given. Training with an E-collar was found to be no more effective than training without, with positive reinforcement found to be the most effective method. The dogs learned to obey commands most quickly when trainers gave consistent signals and rewarded correct responses.

These findings refute claims by some dog trainers that E-collars are a good alternative to reward based training to address highly motivated activities such as wildlife chasing, particularly considering potential risks to the dog's wellbeing, and that their use can lead to unnecessary suffering during dog training.

Professor Jonathan Cooper from the Animal Behavior, Cognition and Welfare Research Group, said: "The Reward-Based Control Group had a higher proportion of obeys after first command to both 'Come' and 'Sit' commands and required fewer multiple commands to initiate a recall or complete a sit response. This suggests that the reward-based training was the most effective approach not only for recall, which was the target behavior in training, but also for other commands. Given the additional potential risks to the animal's well being associated with use of an E-collar, we conclude that dog training with these devices causes unnecessary suffering and increased risk to a dog's wellbeing, without good evidence of improved outcomes."

The work published in Frontiers in Veterinary Science supports legislation against the use of these devices in pet training in place in Wales and Scotland, provides further evidence to support the end of their sale, possession and use across the whole of the UK.


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More information: Lucy China et al. Efficacy of Dog Training With and Without Remote Electronic Collars vs. a Focus on Positive Reinforcement, Frontiers in Veterinary Science (2020). DOI: 10.3389/fvets.2020.00508

Provided by University of Lincoln

Radar developed for rapid rescue of buried people

E A POE APPROVED

by Jens Fiege, Fraunhofer-Gesellschaft

Testing the radar-based detection of the vital parameters of a group of people as they move naturally in an environment at Fraunhofer FHR (from left to right: Siying Wang, Alexander Bauer, Manjunath Thindlu Rudrappa and Reinhold Herschel). Credit: Patrick Wallrath/Fraunhofer FHR

When someone is buried by an avalanche, earthquake or other disaster, a rapid rescue can make the difference between life and death. The Fraunhofer Institute for High Frequency Physics and Radar Techniques FHR has developed a new kind of mobile radar device that can search hectare-sized areas quickly and thoroughly. The new technology combines greater mobility with accurate detection of vital signs.

Some regions of the world record hundreds of earth tremors a day. Most of these are of a minor nature—but occasionally an earthquake strikes of such destructive power that it destroys buildings and triggers tsunamis that lay waste to huge areas. Faced with this kind of disaster, rescue crews often struggle to locate and dig out injured people quickly enough to save them. Although radar devices can provide useful assistance, current systems are limited to stationary operation. Set up in a fixed spot, they can only search up to a distance of twenty to thirty meters, depending on the radar specifications. In disasters involving large-scale destruction, this distance is simply too short.

Based in Wachtberg, Germany, Fraunhofer FHR offers a technology that aims to significantly increase the search radius. "What we've developed is a mobile radar system that locates people buried under rubble by detecting their pulse and breathing," says Reinhold Herschel, a team leader at Fraunhofer FHR. "Our longer-term goal is to mount this radar device on a drone and fly it over the disaster site. This would make searches faster and more effective even in areas extending over various hectares."

Multiple transmitters and receivers enable different vantage points

In basic terms, the radar device works by emitting waves. Part of each wave is reflected by the debris, but some of the wave passes through the rubble and is reflected by people and anything else buried underneath it. The distance to an object is calculated by measuring how long the signal takes to return to the detector in the radar system. If that object is moving—even if it is just a buried person's skin rising and falling by a few hundred micrometers with each heartbeat—this changes the phase of the signal. The same applies to the tiny movements caused by their breathing. People typically take a breath no more than 10 to 12 times a minute, while the heart beats an average of 60 times a minute, so it is relatively simple to distinguish between these different signal changes using algorithms. The researchers can also determine exactly where the buried person is located.


This is made possible by a special type of radar known as MIMO, which stands for multiple input, multiple output. MIMO radars use multiple transmitters and receivers to set up different "vantage points" which can then be used to identify the exact location where paramedics should dig for survivors.

Algorithm detects irregular heartbeats

What is unique about this technology is its combination of mobility and accurate detection of people's vital signs. The mobility advantage generally refers to examples such as mounting the device on a drone and flying it over the disaster site, but it is also possible to turn this principle on its head. Set up the system in a fixed spot, for example, and it can be used to detect the vital signs of people moving around close to the radar. There are a number of situations where this could be useful, such as providing first aid to large numbers of casualties in a sports hall following an earthquake. In this case, the radar device could be used to record vital signs and assign them to each individual to determine who is in most urgent need of assistance. In this example, the algorithm focuses primarily on detecting changes such as whether someone's heart is beating irregularly or a patient is breathing very rapidly. The radar system can distinguish the individual signals and display them separately. Accuracy is also high, with the device measuring pulse rates with 99 percent accuracy as compared to readings taken using portable heart rate monitors. More research is still needed on using the radar to find people buried under rubble, but researchers have already made significant progress in detecting vital signs close to the stationary radar system, successfully putting it to the test at distances of up to 15 meters. The next step towards a viable product would be to conduct a verification study with a partner in the medical arena.

Once the radar system has obtained a positive evaluation based on sufficient data, it can then move into a certification process with interested industry partners. It will probably take around two more years before the developers create a product that is accurate enough to detect buried casualties reliably in tricky scenarios such as soil or concrete and suitable for UAV-based applications. Fraunhofer FHR will be continuing its research in this area to meet this ambitious goal.


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Provided by Fraunhofer-Gesellschaft

America's innovation edge now in peril, says report

by Jeff Falk, Rice University

Credit: Pixabay/CC0 Public Domain

A sweeping new report urges significant policy and funding action to ensure the United States does not lose the preeminent position in discovery and innovation it has built since the end of World War II.

"The Perils of Complacency: America at a Tipping Point in Science and Engineering" was released today by Rice University's Baker Institute for Public Policy and the American Academy of Arts and Sciences.

"The United States became a world power—economically, militarily and culturally—in significant part by placing a high priority on innovation, fueled by advances in science and technology," the report's authors write. "This priority, in turn, required investing in R&D, especially fundamental research conducted in universities and national laboratories across the fields of science, technology, engineering, mathematics and medicine."

China is projected to become the world's largest economy when measured by gross domestic product by 2030, according to the report. "By 2026, the 250th anniversary of the United States, China's strategic plan calls for it to be well on its way to becoming the unchallenged world leader in science, technology and innovation. These developments are perilous for America, which today, 50 years after the Apollo 11 moon landing, is at a tipping point in R&D," the authors wrote.

The report assesses progress and setbacks in the five years since an earlier report, "Restoring the Foundation: The Vital Role of Research in Preserving the American Dream."

It will be discussed in a virtual presentation this afternoon, titled "Inadequate Investment: America, China and the Future of Innovation," which will feature remarks from Norman Augustine, retired chairman and CEO of Lockheed Martin; Neal Lane, senior fellow in science and technology policy at the Baker Institute and former director of the National Science Foundation; and Jeanette Wing, the Avanessians Director of the Data Science Institute at Columbia University and a professor of computer science.

"Recent developments are placing additional stress on the U.S. research system even as they underscore its indispensability in providing the fuel for American innovation and competitiveness as well as the know-how required to address the nation's many societal challenges," the authors write. "As this report was being prepared, a major coronavirus outbreak was impacting thousands of lives in China, America and other parts of the world. Meanwhile, security concerns have led some policymakers to propose draconian restrictions on the very same foreign researchers on whom we have come to rely to fill the persistent domestic talent gap in science and engineering."


One result of recent and proposed immigration restrictions is that other countries have become more competitive at attracting workers, the authors write. The report also says U.S. corporations are now more inclined to move R&D laboratories to other countries. "Compounding this problem is a continued weakness in U.S. support for basic and applied research; the fiscal year 2021 Presidential Budget Request would cut federal support for these categories by $7.9 billion, or just over 9%," the authors wrote.

2020 priorities

The authors expand on the recommendations outlined in the 2014 report, which focused on R&D priorities, and urge action to strengthen STEM education and the American workforce.

"The nation's pre-K–12 public education system has been in crisis for decades, and the urgent need to improve student achievement was one of the seven priorities listed in the 'Innovation: An American Imperative' call to action that was supported by over 500 organizations across the country," the authors wrote. "The National Academies of Sciences, Engineering and Medicine, in its 'Gathering Storm' report, laid out a strategy to address this crisis."

The report also recommends states return to providing sustained public university funding to the levels per student, in real dollars, that were in place prior to the 2008 recession.

"Restoring state funding for universities will enable those institutions to better serve the educational needs of the state's citizens, raise the skill level of the workforce, support full employment, form stronger partnerships with local companies and contribute to the country's overall science and technology enterprise," the authors write.

"The recent tax placed on the earnings of endowments of (private) universities represents an altogether counterproductive trend and should be repealed promptly," the authors write. "Repealing this punitive tax will help universities control tuition, provide more financial aid and maintain modern research and teaching facilities. Doing so will also, hopefully, discourage further such narrowly targeted, counterproductive approaches."


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More information: Restoring the Foundation: The Vital Role of Research in Preserving the American Dream: www.amacad.org/publication/res … rving-american-dream

Provided by Rice University

Existing political tensions intensify during pandemic: A 'glocal' observation

by Jonatan A Lassa, Ermi Ndoen, Rudi Rohi, Victoria Fanggidae, The Conversation

Credit: Pixabay/CC0 Public Domain

Tensions have been rising between the Indonesian central government and the Jakarta administration over differences in dealing with the pandemic, leading to confusion and concerns about scattered strategies in mitigating the crisis.

In September, when hospitals in the country's capital were nearly full, Jakarta Governor Anies Baswedan made a critical and justified decision to reactivate the lockdown policy—known locally as large-scale social restriction, or PSBB.

Anies claimed the central government fully supported his decision.

The next day, President Joko "Jokowi" Widodo, said he was concerned Anies' decision to limit public mobility and business operations in the capital could worsen the economic downturn.

In saying this, Jokowi contradicted his previous statement that putting the economy before health was dangerous.

Why do jurisdiction tensions—in this Indonesian case, between the president and Jakarta governor—happen in such a crisis?

We argue that existing political tensions (either latent or open) are often intensified during crises and disasters.

Worsening gaps

Anies—Jokowi's former education minister turned political opponent – is a potential candidate for the 2024 presidential election.

The pandemic can intensify prior political divides. The amplifying of existing relational gaps between jurisdictions sometimes reveals deeper layers of conflict.

Political economic variables, such as rent-seeking and power interests, might explain the tension between central and local governments.


However, we argue that a genuine conflict can also arise based on a clash of crisis management imperatives. Each leader at a different level of jurisdiction understands the crisis and responds differently according to their own biases.

At least three types of biases can be observed during this pandemic: border bias, projection bias, and normalcy bias.

Border bias is an illusion that administrative boundaries can physically limit the spread of disasters.

This territorialism approach is often inadequate when facing large-scale catastrophes and crises that are trans-boundary in nature.

Projection bias prompts leaders to project their current mindsets and assumptions into an uncertain future.

For example, seeking to leave an economic legacy in his last term, Jokowi has become indecisive throughout the pandemic. He is reluctant to put "human first, economy second."

Public leaders in disaster and crisis settings often adopt normalcy bias—a habit of underestimating the probability of disruptions. They tend to accept interpretations that favor their interests and biases.

The interplay of the above biases compromises crisis-management decision-making during COVID-19.

Existing political divides are amplified during disasters when public leaders from different parties at different jurisdictions get involved.

In the United States, a similar conflict exists between President Donald Trump (a Republican politician) and New York State Governor Andrew M. Cuomo (a Democrat) over the issue of quarantine.

In Australia, Victorian Premier Daniel Andrews (of the Labor Party) adopted a strict lockdown policy. This went against the policies of Prime Minister Scott Morrison (of the Liberal Party) who favors "re-opening the economy faster by improving COVID-19 contact tracing."

A debate about which level of government was responsible for the high death toll at aged-care facilities locked the Australian federal and Victorian state governments into a feud. In Australia, the pandemic also induces state rivalries and parochialism.

Conflicts like these occur around the world, from Europe to Latin America, with variations in complexity and intensity.

In Indonesia, we can also see such tension between lower-level governments.

In the province of East Nusa Tenggara, the municipal administration of Kupang recently decided to restrict movements out of concern that it didn't have enough capacity to handle an increasing number of COVID-19 cases.

Within hours, the provincial administration overruled the policy. It allowed mass gathering and parties as long as they complied with COVID-19 protocols, arguing that economic activities have to continue.

In East Java, the provincial administration and the municipal administration of the province's capital city, Surabaya, disagree on COVID-19 management issues such as allocation of mobile test labs, lockdown timeframe, hospital admission and transparency about new clusters.

Leaders of these administrations come from different political parties. While they are part of the same national coalition, they have different interests in the upcoming local election.

What is the public to do

There is no "one size fits all approach" to contain virus transmission. Even so, we can attribute a certain level of success to measures such as safe distancing, high testing rates, adequate contact tracing and quarantine, listening to experts and strategic border controls.

Whatever political parties or ideologies are in power, the public must pressure their governments to adopt those measures.

The public must scrutinize decisions made by any democratically elected government.

How a policy is made (whether it is scientifically based) and its objectives (to contain, to suppress, or to "live with" the virus) are more important than who made it and which parties they are from.

Some encouraging evidence has shown that at the community level this approach works.

Villagers of Panggungharjo in Bantul, Yogyakarta, established a collaborative response model where they developed their own measures to protect themselves from the pandemic.

These include monitoring movements of people in and out of the village and allocating rooms for village-level quarantine. They also encouraged community trading via an e-commerce platform.

The challenge is to upscale such collective consciousness and solidarity to the municipal, provincial and higher levels.


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Provided by The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.