It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Saturday, October 14, 2023
New biobased recyclable polyesters exhibit excellent tensile properties beyond polyethylene and polypropylene
The research group of Professor Kotohiro Nomura, Tokyo Metropolitan University, in cooperation with the research group of Director Hiroshi Hirano, Osaka Research Institute of Industrial Science and Technology, has developed biobased polyesters from inedible plant resources, which can be easily chemical recyclable and exhibit promising mechanical properties in films than commodity plastics.
The development of high-performance, sustainable, recyclable plastics is important for the creation of a circular economy. Biobased polyesters made from plant resources are expected to become a promising alternative to commodity polymers such as polyethylene and polypropylene produced from petroleum. However, there have been few examples of the development of high-performance materials that exceed required mechanical properties such as tensile strength and elongation at break.
Synthesis methods for high molecular weight (long chain) polymers had been a pending issue in conventional polycondensation methods. To solve this issue, the research group has developed an olefin metathesis polymerization method using a high-performance molybdenum catalyst, focusing on polyesters derived from inedible plant resources.
In general, there is an antinomic relationship between tensile strength and elongation at break in polymer film, as well as an increase in the molecular weight and the elongation at break. However, the present polymer film demonstrates that the tensile properties (strength and elongation at break) of the polymer film increased with the molecular weight, exhibiting superior properties beyond conventional plastics.
This method is the first success in developing the biobased polyester materials that can be decomposed/recycled. The film properties can be further improved by combining the material with naturally derived fibers such as cellulose nanofibers.
Basic design, structure of present biobased polyesters Basic structure, framework in the present biobased polyesters derived from plant oil and glucose (in this study). The present polymers can be easily decomposed to the monomer units by chemical recycle simply using treating with alcohols (called catalytic transesterification). Credit: JST
Promising mechanical properties in the present biobased polyesters byond polyethylene Effect of molecular weight toward tensile properties in the present biobased polyesters, HP1. The plots of PE-18,18 (polyester-18,18, reported biobased), and commercially available polyethylene terephthalate (PET), poly(lactic acid) (PLA), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), and polystyrene (PS) are placed for comparison. In general, polymer films exhibiting higher tensile strength (with increase of molecular weight) tends to decrease the elongation at break. The present high molecular weight biobased polyester (HP1), achieved in this study, shows promising tensile properties (tensile strength, elongation at break) beyond commodity plastics. The success was enabled by synthesis of high molecular weight polymers by high performance molecular catalyst. Credit: JST
Olefin metathesis polymerization method
"Olefin" is a general term for hydrocarbons with one carbon–carbon double bond. The word "metathesis" means "substitution." Therefore, the recombination reaction of substituents on the double bond of an olefin is called the olefin metathesis reaction. For example, there is a reaction where a carbon–carbon double bond in an olefin is replaced with a catalytic metal–carbon double bond (catalytically active species) through the reaction using a catalytic metal such as ruthenium or molybdenum.
The polymer synthesis method using such a reaction is called the olefin metathesis polymerization method. The present method developed by the researchers is a polycondensation synthesizing polymer through producing ethylene as by-product (acyclic diene metathesis polymerization).
More information: Mika Kojima et al, Synthesis of High Molecular Weight Biobased Aliphatic Polyesters Exhibiting Tensile Properties Beyond Polyethylene, ACS Macro Letters (2023). DOI: 10.1021/acsmacrolett.3c00481
Diagram of the experimental setup. Credit: Dr Ryan Ward
The University of Liverpool is part of a new study that reveals for the first time how particular scents can influence our perception of color.
In a paper, titled "Odors modulate color appearance," published in the journal Frontiers in Psychology, an interdisciplinary research team of University of Liverpool psychologists and engineers undertook an experiment to determine if smell does indeed influence how we perceive color.
The experiment involved 24 participants aged 20 to 57 sitting in front of a screen in an isolation room with blacked out windows, and no unwanted sensory stimuli or odors.
Then an ultrasonic diffuser released one of six scents—caramel, cherry, coffee, lemon, and peppermint, plus odorless water as a control—into the room. The scents were chosen as they induced the most robust odor-color associations in the team's prior work.
The participants were then asked to modify a square filled with a grayish color on a screen using two adjustable sliders—one yellow to blue and another one red to green—until they reached a color they judged as being devoid of any hue, that is, a perfect neutral gray color.
The results revealed that participants chose a more red-brown color gray when they smelt coffee, while opting for a yellow-brown version of the gray when the odor of caramel was pumped into the room.
The lead author of the paper is Dr. Ryan Ward, a senior lecturer at Liverpool John Moores University, who undertook the study when he was with the University of Liverpool's Department of Electrical Engineering and Electronics (EEE) and University of Liverpool's Digital Innovation Facility (DIF).
He said, "Here we show that the presence of different odors influences how humans perceive color. Our results showed that the perception of gray trended towards their anticipated correspondences for four out of five scents, namely lemon, caramel, cherry, and coffee."
The research is part of an unusual but exciting collaboration between Professor Alan Marshall, from the University's Department of EEE who heads up the Immersive Reality laboratory at the DIF, and Sophie Wuerger, Professor of Vision Science with the Department of Psychology.
They are working together to explore how olfactory information can be sent remotely and also how it influences our perception. Their longer-term research focus is the effective inclusion of olfactory information in Virtual Reality using their interdisciplinary expertise and the unique facilities in the Immersive Reality laboratory at the DIF.
Professor Wuerger said, "Research on the interactions between the sense of smell and vision is a fairly new area. The novelty of our experiment is that we used a robust tool to measure small perceived color changes and assess the perceived color in a more objective way which requires know-how of vision science. We believe we are the first team to do this."
Professor Alan Marshall said, "This is an exciting area of research which is important if we are to understand better how our senses influence our overall perception, which will also be a critical factor in designing the next generation of 'immersive reality' systems, such as the Metaverse, and has application not just in entertainment, but across a wide range of VR systems including the creative arts, training, education and health care."
More information: Ryan J. Ward et al, Odors modulate color appearance, Frontiers in Psychology (2023). DOI: 10.3389/fpsyg.2023.1175703
Climate researcher rejects being sacked for refusing to fly
Credit: Pixabay/CC0 Public Domain
A climate researcher hit back against his dismissal from a German think-tank after refusing to take a flight back from a fact-finding mission in Papua New Guinea.
Gianluca Grimalda was informed of his dismissal in mid-October by his employer, the Kiel Institute for the World Economy (IfW Kiel), in a letter seen by AFP on Friday.
No reason for the termination was given in the letter.
A few days before, the 51-year-old social scientist had received an ultimatum from the institute, insisting he return to Germany by plane.
"I'm not going to catch a plane because for me it's unreasonable," Grimalda told AFP, who refused the demand to travel.
The Italian national spent the best part of the last six months investigating the social impacts of climate change on communities in Papua New Guinea.
Grimalda, who is a member of the climate activist group Scientist Rebellion, had traveled most of the way to the Pacific island state by land and sea.
Around two-thirds of the 22,000-kilometer (13,670-mile) journey from Germany was done by train, car and boat.
Grimalda intended to do the same for the return leg and was set to arrive back in Kiel on September 10.
But Grimalda's return was delayed when he ran into difficulties with former independence fighters in the region and a volcanic eruption forced part of his trip to be cancelled, according to the researcher.
The institute in Kiel was frustrated by the delay and asked Grimalda to return by October 2, according to another letter seen by AFP.
Grimalda said he suffers from medically diagnosed "climate anxiety" and risked succumbing to a panic attack if he boarded the flight back to Germany.
The researcher said he would contest his dismissal from the institute when he returns to Germany, citing mental health reasons.
Contacted by AFP, the IfW Kiel said it did not comment on internal personnel questions to "protect the private lives of employees".
How clouds protect coral reefs, but will not be enough to save them from us
by Pedro C. González Espinosa and Simon Donner, The Conversation
Credit: Unsplash/CC0 Public Domain
Coral reefs are vital ecosystems for people and coastal communities. They provide food and livelihoods and protect coastlines from storms, contribute to local economies and preserve cultural heritage.
However, warming ocean temperatures as a result of human-made climate change present considerable risks to the reefs. The recent rise in coral bleaching all over the world is the most visible impact.
But what is coral bleaching? Coral bleaching is a phenomenon that occurs when the white skeleton of the corals becomes visible after the microalgae that live inside their translucent tissues are expelled.
Even though coral reefs can recover from bleaching events, the process, much like the regrowth of a forest following a windstorm or wildfire, requires a considerable amount of time. And, as our research has shown, an appreciation of the role of cloud cover.
If the temperatures are high enough, the coral and microalgae become more light-sensitive. When combined with excessive sunlight, this sensitivity harms the microalgae which, in turn, results in the production of chemical compounds called reactive oxygen species. These compounds are harmful to many species and in the case of reefs cause the coral to expel its microalgae.
In the same way that clouds protect us from harmful exposure to UV rays, clouds also provide a protective barrier for the world's coral reefs. Field studies of coral bleaching events in French Polynesia and in the Republic of Kiribati found that periods of cloudiness may have reduced the bleaching severity and extent.
Climate change is projected to kill off most of the world's coral reefs, even in scenarios with only 1.5°C of global warming. Yet, to date, most analysis has only considered the effect of temperature. Could incorporating clouds change the forecast?
Considering cloudiness
In order to understand how cloudiness might influence the response of coral reefs to climate change, our recent study used a global historical database containing almost 38,000 coral bleaching reports to train an algorithm that estimates bleaching severity based on incoming light and temperature stress.
Our algorithm was then applied to four different future climate scenarios on the world's coral reefs to assess if and when bleaching conditions would become too frequent for reefs to recover. The results indicate that under a low emissions scenario, increased cloudiness would indeed have an effect on the coral bleaching conditions. This means that corals would have more time to recover from the impacts of rising temperatures and improve their resilience.
However, even under a low carbon emission scenario, this extra time will not be enough to prevent more than 70 percent of global reefs experiencing frequent bleaching conditions with not enough time in between to fully recover.
This highlights the severity of the coral bleaching crisis caused by thermal stress and the limitations of relying solely on cloudiness as a protective mechanism. Simply put, while clouds can offer some relief to corals, they cannot mitigate the long-term consequences of climate change when the sea surface temperature becomes too high.
Clear implications
Cloud cover may offer temporary relief to coral reefs by delaying the adverse environmental conditions responsible for coral bleaching. However, that seems to be partially true only in the lowest emission scenario which would be possible only if we dramatically cut greenhouse gas emissions.
Without doing that, dangerously frequent bleaching conditions are unavoidable and reefs will continue to be threatened even if we cut down emissions now. Moreover, we also need to get serious about habitat and biodiversity protection to increase resilience.
Only by doing this could coral reefs stand a chance at surviving the increasing pressures of climate change. Any other approach has its head in the clouds.
The Mauritius Supreme Court has declared unconstitutional a law that criminalizes consensual same-sex acts between adult men. The decision boosts the trend in the Southern African Development Community (SADC) region towards decriminalization. Now, a slight majority—nine out of 16 member states—do not prohibit gay and lesbian sexual relations.
I have researched and taught human rights law in Africa, including the rights of sexual minorities, for over three decades, and closely follow the work of the African Commission on Human and Peoples' Rights.
The African Commission, as the continent's human rights custodian, should lend its unequivocal support to the decriminalization trend. This is particularly significant as attempts are made to further criminalize and stigmatize sexual minorities in parts of Africa.
The commission has not yet expressed its view on the decision. Its 77th ordinary session, starting on 20 October 2023 in Arusha, Tanzania, is an opportunity to do so. It should build on its 2014 guidance to African states on eradicating violence based on sexual orientation and gender identity.
The litigant, Ah Seek, a gay Mauritian man and board member of the Mauritian NGO Collectif-Arc-en-Ciel, invoked a number of constitutional grounds. However, the court based its decision on the most directly relevant ground: the right not to be discriminated against.
In addressing two issues that could militate against a finding in Ah Seek's favor, the court relied on the approach of other courts in the SADC region. The 2021 judgment by Botswana's Court of Appeal was particularly relevant. This judgment held that the constitutionally protected ground of "sex" in the Botswana constitution encompassed "sexual orientation."
The first issue was the contention that Mauritius' constitution does not explicitly prohibit discrimination based on "sexual orientation." The relevant provision (section 16) forbids discrimination on the basis of seven specified grounds, including sex.
The Mauritian court concluded that the word "sex" in section 16 of the constitution includes "sexual orientation."
The court also emphasized the country's international human rights commitments. It said that, as a state party to the International Covenant on Civil and Political Rights, Mauritius was expected to interpret its constitution in line with this treaty.
The second issue was whether the rarity of prosecutions removed the need for the court to decide. Referring to a judgment by the South African Constitutional Court, the Mauritius court held that the mere threat of arrest, prosecution and conviction "hangs like the sword of Damocles over the heads of homosexual men."
The court therefore concluded that the constitution protected everyone from discrimination based on their sexual orientation, whatever it might be.
When it was given an opportunity to show any legitimate purpose for this form of discrimination, the state merely made reference to same-sex relations as a "highly sensitive issue" due to the "delicate socio-cultural and religious fabric of Mauritian society." Rejecting these as justifications for discrimination, the court underlined that Mauritius was a secular state.
Regional trend
Greater societal acceptance of homosexuality can be both a catalyst for and a consequence of decriminalization of same-sex relationships.
In a recent survey by the independent African surveys network Afrobarometer, Mauritius featured prominently as a country in which tolerance (towards an LGBT person as neighbor) had increased from 2014 to 2022.
Nine of the 11 African countries with an above-average tolerance percentage towards LGBT persons were from the SADC. All of these 11 states, except Eswatini, have decriminalized "sodomy laws."
The conditions for decriminalization seem to be converging in Eswatini. Its population displays a relatively high level of acceptance (of 42%) in the survey. Also, its Supreme Court has signaled some openness to uphold LGBT persons' rights.
Besides Eswatini, other SADC member states that still retain "sodomy" laws are Comoros, Malawi, Namibia, Tanzania, Zambia and Zimbabwe. With the exception of the Comoros, the laws of these states are relics from British colonial times, when "sodomy" laws were imposed as part of a colonial "civilizing" mission. The Mauritius Supreme Court noted that, as a colonial import, section 250 did not reflect Mauritian values and was not the "expression of domestic democratic will."
Today, just over half of the SADC states do not criminalize same-sex relationships between consenting adults. The Democratic Republic of Congo never legislated on this matter. In Lesotho (2012), the Seychelles (2016), Mozambique (2015) and Angola (2019), the legislature in the last decade or so adopted a new version of the penal code. These offenses, stemming from the English common law or the 1886 Portuguese Penal Code, were omitted. In Madagascar, the penal code criminalizes consensual same-sex acts only with a person under 21 years old.
Still, the situation remains in flux. In Malawi and Namibia, litigation on related penal code provisions is pending. In Malawi, then President Joyce Banda in 2012 committed to repealing these laws. There was also a moratorium on arrests and prosecutions between 2012 and 2016, and a court-ordered review of the constitutionality of "sodomy laws."
In Namibia, the Supreme Court decided in 2023 that Namibia must recognize same-sex marriages validly concluded outside the country.
Diverging trend
In the rest of Africa, the position of sexual minorities is much more precarious. Thirty-one (almost 58%) of countries still criminalize consensual same-sex acts between adults. The trend is towards more restrictive laws and harsher punishment.
In Ghana, the Promotion of Proper Human Sexual Rights and Ghanaian Family Values Bill is being considered.
In Kenya, the anti-gay Family Protection Bill carries a 50-year jail term. But the Supreme Court decided in February 2023 to allow the NGO National Gay and Lesbian Rights Commission to be registered.
These laws were initiated as private members bills. They are driven by individuals rather than any political party's agenda, and bolstered by an anti-LGBT solidarity conference of African parliamentarians.
African Commission's role
Against this background of opposing forces and divergent trends, the role of the African Commission is all the more important. The commission itself has sent mixed signals. It affirmed the right to dignity and bodily integrity of sexual and gender minorities. But it also refused to grant observer status to NGOs working to promote these rights.
Bank CEOs set the tone from the top when it comes to risky behavior, new research suggests
by Alper Kara, Artur Semeyutin and Said Kaawach, The Conversation
Credit: KeyStock/Shutterstock
Metro Bank positioned itself as "a fresh start to banking" when it launched in the wake of the 2008 global financial crisis. It was set up in 2010 as a challenger to the "big five" banks dominating the UK market post-crisis: HSBC, NatWest, Lloyds, Barclays and Santander.
But more recently, Metro Bank has caused concern among its investors for not meeting regulatory requirements on its capital levels. These rules dictate the amount of capital the bank must hold based on the riskiness of its assets, so that it can still operate but also meet any customer withdrawal requests. The riskier the bank's activities, the more capital it must have on hand.
Regulators use such rules to ensure that banks are keeping people's money safe. Banks can also help by creating a culture that doesn't value excessive risk-taking. Our new research shows the extent to which top executives at banks set the tone on risk-taking. The way CEOs and even CFOs talk about risk can offer insights into a bank's likely financial stability. A more relaxed attitude could be a valuable early warning sign of potential bank distress for regulators.
Metro Bank is currently operating normally and there is no reason to think its customer deposits are in danger. It has secured new financing, and plans to open 11 more branches. But ongoing struggles with regulatory capital levels means its business model is still being questioned by analysts.
Challenger banks like Metro are often viewed as disadvantaged because they need to keep more money on hand, compared with the UK's big five. This adds to their costs.
The UK regulator recently rejected Metro Bank's request to reduce its capital levels, triggering the latest concerns about its stability and causing it to seek more investor funding. The bank subsequently secured this funding, calling it "a new chapter … facilitating the delivery of continued profitable growth over the coming years."
Policymakers around the world introduced extensive reforms to banking and financial regulation after 2008, to protect financial stability and avoid a repeat of this economic catastrophe. This explains the current tough stance by regulators towards relaxing rules for organizations such as Metro Bank.
UK financial authorities have even recently called out UK government plans to ease financial regulations under the Edinburgh Reforms and to remove the bankers' bonus cap, in case it encourages more risk-taking by banks.
Recent bank failures: A stark reminder
Regulators, as well as financial market participants, also remain vigilant after the unexpected failure of a number of banks earlier this year. In particular, the collapse of Silicon Valley Bank (SVB) in the US was attributed to poor risk management. It fueled fears about global financial stability and the possibility of yet another devastating crisis.
However, regulation alone is not enough to mitigate excessively risky behavior. The attitude to risk that runs through a bank—its risk culture—also matters.
A company's risk culture comprises a set of values, attitudes and behavior related to the awareness, management and control of risks. It shapes decisions about things like who to lend to, what to invest in, and how to manage the risks that arise as a result.
Most banks' business models rely on balancing risk management with profit maximization in this way. But it needs to be done responsibly: signs of poor risk culture, such as excessive risk taking or misconduct, are red flags to regulators and investors.
But it's difficult for outsiders, even regulators, to observe and measure a bank's risk culture. So, our recent study aimed to quantify the risk culture of 160 US banks, including some of the country's largest. We did this by analyzing the text of conference calls on which their CEOs answered questions about the business from analysts, investors and the media. This allowed us to capture their unscripted views and behavior when these bank CEOs were put on the spot.
We used a machine learning algorithm to construct a dictionary of words and phrases associated with seven different risk culture dimensions, including "risk strategy" and "regulatory requirements." We used another algorithm to assess whether these phrases were being used in a positive or negative way.
Our analysis showed that words and phrases associated with the "regulatory requirements" risk culture dimension, for example, were mentioned the least by CEOs prior to and during the global financial crisis. Unsurprisingly, use of the term picked up in its aftermath, as CEOs had to explain how tightening banking regulations were affecting their businesses.
By calculating the number of positive and negative occurrences of each phrase, we were able to create a measure of CEO attitudes for each risk culture dimension. We found that a weaker risk culture—characterized by more negative mentions of these phrases—indicated a greater probability of bank insolvency as a result of not having enough capital.
More worryingly, we found similarities in attitudes to risk between collapsed US banks SVB and First Republic, and other US banks that are still operating today.
Our research indicates that a strong risk culture in banking starts with the right tone from the top. Executives should be aware of their role model status when making decisions and talking about risk, both within their companies and to the public. Their attitudes cascade down to every other level and, if they are serious about managing risk, this could help maintain financial stability not only of their own bank, but the financial sector as a whole.
US astronaut gets used to Earth after record-setting 371 days in space
In this handout photograph taken and released by Roscosmos on September 27, 2023, Expedition 69 NASA astronaut Frank Rubio is helped by specialists after his landing in the Soyuz MS-23 capsule in a remote area near the town of Dzhezkazgan, Kazakhstan.
After spending more than a year in space, Frank Rubio now has to get used to that pesky thing Earthlings call gravity.
"Walking hurts a little bit the first few days, the soles of your feet and lower back," he said at a news conference Friday at NASA's Johnson Space Center in Houston, Texas.
"I think there is a certain level of pain that comes with the fact that your lower back now supports half your weight."
Rubio returned to Earth two weeks ago after spending 371 days in space, having taken off in September of last year aboard a Russian rocket for what was supposed to be a routine, six-month mission.
The Soyuz spacecraft that was supposed to bring them back was docked at the International Space Station to be used as an emergency backup vehicle. But then it sprung a coolant leak in December, probably due to a micrometeoroid.
So as a precaution, the Russian space agency, Roscosmos, returned the vessel to Earth.
It sent another, empty one—which meant there would be space for Rubio and company to return, but they'd have to pick up the mission slated for the crew originally meant to be on that second ship.
"The fact that I was going to spend a whole year cooped up was a kind of torture for me, because I love being outside," Rubio said.
"But that's part of the mission. It took a little bit of a mental shift and saying, 'Hey, this is my world for the next 12 months and I have to deal with that.'"
But the misadventure allowed this son of Salvadoran immigrants to grab the record for the longest time an American has spent in space, breaking the 2022 record set by Mark Vande Hei, at 355 consecutive days.
The world record is held by Russian cosmonaut Valeri Poliakov, at 437 days.
"For the first few days (back on Earth) you drift to the right or to the left as you try to walk straight," he says.
"Your mind is perfectly clear, but your body just doesn't respond the way you expect it to."
During his stay at the ISS, Rubio notched another potential first when he grew a tomato.
"I think what was the first tomato in space," he said.
He put it in "a little bag" and fastened it down with Velcro, but ended up losing track of it.
Rubio spent hours looking for it to no avail. It may have dried out and been mistaken for garbage.
But "some people will say I probably ate it," he jokes.
Researchers at the Kostas Research Institute found a component in squids and octopi can be used to create paints that change colors in different lights. Credit: Alyssa Stone/Northeastern University
When you think of an octopus, you might be envious of its eight limbs. After all, there's a lot to be done with eight arms. But scientists are a bit more interested in something else: its skin.
Cephalopods—like octopi and squid—change colors rapidly in response to threats or even just changes in light thanks to xanthommatin, a naturally occurring dye present in their bodies. Researchers at Northeastern University's Kostas Research Institute (KRI) work with a synthesized version of this dye, experimenting to create colorants that change in response to different stimuli. Their latest discovery: using this to create paint that can change colors when exposed to light.
KRI focuses its work on interesting components from natural materials, Cassandra Martin, a research scientist at the institute, said, looking into ways those components can be replicated and used in the real world. Cephalopods have been a starting point due to the unique nature of their skin.
"Their color change is so rapid and it's so vibrant and it's so intense," Martin said. "There's not a lot of natural systems out there that change that fast and there's not a lot of color-changing materials that are that fast without requiring a lot of external (changes)."
Last summer, Kaitlyn Flynn, then an intern/visiting student, was working on a project using this colorant and decided to further research how to do this. She and the team found that titanium dioxide served as a conductor for the color change. Mixing different amounts with the xanthommatin could speed up the change or add to the intensity of the color shift.
The changes can happen in as quickly as five minutes and can last as long as 24 hours, depending on how long the paint is exposed to light. The colorant can easily be made in as little as two hours and added to water or oil-based paints.
"We've imagined a scenario where if you want to have art that changes from day to day on an interior wall, like maybe in a coffee shop or something you could use a regular projector to project a pattern onto the wall, temporarily paint in this color and this pattern or this art, and then over time that fades away and you can redo it again, ideally as many times as you want," Wilson said. "We can create temporary artwork or art or paint that could potentially track the weather or track the environment that it's in."
Besides the ability to create temporary art, this discovery has environmental implications. It can serve as an eco-friendly alternative to paints currently on the market.
"Paints that are like commercially used nowadays can have harmful chemicals in them, so they can have things that can be harmful to the people that are painting them," said Flynn who is now getting her Ph.D. in chemistry at Northeastern.
"The fumes can be super harmful. They can be harmful long term if you're exposed to them for a long time. They can also leach out into the environment. Searching for a more natural way to make these paints creates a safer environment for the people using it and for the people that are going to be exposed to it."
Moving forward, Flynn and Martin said they hope they can apply this system to other materials and expand beyond the yellow-red color palette they used in the initial experiment. They also hope to get to the point where the user can decide how quickly they want the colors to change on the paint.
More information: Cassandra L. Martin et al, Color‐Changing Paints Enabled by Photoresponsive Combinations of Bio‐Inspired Colorants and Semiconductors, Advanced Science (2023). DOI: 10.1002/advs.202302652
