Wednesday, December 18, 2024

Ocean microbe’s unusual pair of enzymes may boost carbon storage, study suggests



Stanford scientists have discovered multiple forms of a ubiquitous enzyme in microbes that thrive in low-oxygen zones off the coasts of Central and South America


 News Release 
Stanford University





Stanford researchers have found a surprising genetic twist in a lineage of microbes that may play an important role in ocean carbon storage. The microbes, known as blue-green algae or cyanobacteria, have two different forms of a ubiquitous enzyme that rarely appear together in the same organism. 

“This is one of those great examples of science where you go out looking for one thing, but you end up finding something else that’s even better,” said Anne Dekas, an assistant professor of Earth system science at the Stanford Doerr School of Sustainability and senior author of the Nov. 25 study in Proceedings of the National Academy of Sciences

Billions of years ago, long before plants arrived on the scene, cyanobacteria invented oxygenic photosynthesis. In the process of producing food from carbon dioxide and sunlight, the widespread microbes released oxygen into the air, making our planet’s atmosphere hospitable to the array of life on Earth today. “Cyanobacteria are arguably the most important life form on Earth,” said Dekas. “They oxygenated the atmosphere of Earth and created a biological revolution.”

Special cyanobacteria

Like plants, cyanobacteria use an enzyme called ribulose bisphosphate carboxylase, or RuBisCo, to convert carbon dioxide into biomass. One of the most abundant proteins in nature, RuBisCo comes in several forms: The most common type, known as form I RuBisCo, often uses a structure called a carboxysome to selectively react with carbon dioxide but not oxygen, allowing photosynthesis to proceed efficiently. Organisms with a less common type of the enzyme, known as form II, lack a carboxysome and can effectively build biomass from carbon dioxide in environments where oxygen is scarce. 

Usually, organisms have only one form of RuBisCo, said lead author Alex Jaffe, a postdoctoral scholar in Earth system science. So he was surprised when he happened upon an exception to that rule while studying carbon fixation in ocean microbes. Jaffe was analyzing DNA from seawater samples collected from deep waters off the coasts of Central and South America when he noticed that some shallow water DNA samples had accidentally slipped in. He discovered that cyanobacteria in these samples seemed to have genes for both RuBisCo forms. “My initial reaction was this is probably wrong,” said Jaffe. 

Further research confirmed that both forms of the enzyme were present and actively used for photosynthesis in the cyanobacteria from shallow water, although additional testing will be required to understand how cyanobacteria use the two forms. “By having two versions,” said Jaffe, “it might allow you to remove more carbon dioxide from the water than if you only had one of them, or potentially to do it a little bit more efficiently.”  

Efficiency might be key to survival where the samples originated, in an oxygen minimum zone about 50 to 150 meters below the surface, where oxygen and light are both in short supply. “It’s very hard to live there,” said Dekas. “For a photosynthetic organism, when you have low light, you have little energy.”

Carbon storage and extra-efficient crops

The findings could help scientists anticipate how the ocean’s capacity to sequester carbon may shift as climate change expands low-oxygen zones. The revelation that some cyanobacteria have both forms of RuBisCo suggests they may store carbon more efficiently than previously understood and could proliferate along with expanding oxygen minimum zones. 

If two RuBisCos are in fact better than one, the finding could also lead to more efficient crop production. For decades, researchers have tried to engineer form I RuBisCo to enable crops that grow more with less fertilizer and water. “We’re looking forward to continuing to think about this with people who work on the plant engineering side to see whether it might yield some fruit, literally and metaphorically,” said Jaffe.

The findings gave Jaffe a new appreciation for life’s ability to adapt to challenging environments. “These genes, despite being central to organisms’ metabolism, can actually be quite flexible and can be reconfigured and shuffled in ways that we didn’t expect,” he said.


Co-authors include Navami Jain, MS ’24, who worked on the research as a graduate student in biomedical informatics in the Stanford School of Medicine. Additional co-authors are affiliated with University of Washington; University of California, Berkeley; the Joint BioEnergy Institute; and Lawrence Berkeley National Laboratory. 

This research was funded by the Stanford Science Fellows program, the National Science Foundation, and the Simons Foundation.

 

 

The high cost of carbon


The social cost of carbon, a crucial tool for setting climate policy, omits key effects



University of California - Davis

Alaska oil pipeline 

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An oil pipeline in Alaska, north of Fairbanks. A UC Davis- led study finds the social cost of carbon — a figure used for climate policymaking that quantifies the damage a ton of CO2 has on society and the economy— is too low. 

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Credit: Malcolm Manners



The social cost of carbon — an important figure that global policymakers use to analyze the benefits of climate and energy policies — is too low, according to a study led by the University of California, Davis.

The study, published today in the journal Proceedings of the National Academy of Sciences (PNAS), shows that current estimates for the social cost of carbon, or SCC, fail to adequately represent important channels by which climate change could affect human welfare. When included, the SCC increases to just over $280 per ton of CO2 emitted in 2020 — more than double the average published in the academic literature. The study’s estimate is also larger than the U.S. Environmental Protection Agency’s central estimate of $190 per ton of CO2. 

“When people worry about climate change, they worry about the risk and uncertainty it causes,” said lead author Frances Moore, an associate professor in the Department of Environmental Science and Policy at UC Davis. “They worry about long-term, persistent accumulating effects, such as climate change acting as a drag on economic growth. They worry about impacts to very unique natural systems or cultural heritage that are just irreplaceable. Those are what keep people up at night about climate change, and those are not fully included in SCC estimates currently used for policymaking.”

Climate change and the damage done

The social cost of carbon quantifies the damage a ton of carbon dioxide has on society and the economy, including food production, human health, property damage due to natural disasters, and impacts to natural systems. Estimates of the SCC are used widely in policy analysis, particularly to value the benefits of reducing greenhouse gas emissions. The United States, Germany, Canada and several states all have official SCC estimates used for policy making.

Most current government estimates, the study said, are incomplete and likely underestimate the benefits of reducing greenhouse gas emissions. This is because they omit some important ways climate change can affect human welfare, including via economic growth or effects on unique natural systems.

The study combines evidence from both the published literature and a survey of experts to fully integrate these elements into the SCC estimate, providing the most comprehensive assessment of SCC estimates to date.

Accounting for omissions

For the study, the authors synthesized 1,800 SCC estimates from the academic literature over the past 20 years and found a wide range of published values averaging $132 per ton of CO2.

The scientists also conducted an expert survey with the authors of the literature, who said they thought the true value of the SCC was likely twice as large as the average of published values. Experts attribute this to a range of omissions in the academic literature, including limited representation of climate tipping points, effects on scarce ecosystems, or climate impacts with long-lived effects on the economy such as impacts on economic growth.

The authors then used machine learning to re-weight the literature, partially correcting some of the omissions identified by experts and using more recent evidence on discount rates. This produced a distribution of the 2020 SCC with a mean of $283 per ton of CO2 and an interquartile range of $97 to $369.

The study states: “Incorporating climate costs into the prices of economic activities that emit greenhouse gases, either directly through carbon pricing or indirectly through emission regulation or subsidies of cleaner alternatives, is essential for averting the worst climate outcomes.”

The study’s coauthors are Moritz Drupp from the University of Hamburg, James Rising from the University of Delaware, Simon Dietz from the London School of Economics and Political Science, Ivan Rudik from Cornell University, and Gernot Wagner from Columbia Business School.

 

 

Paranoia may be, in part, a visual problem



Yale University





New Haven, Conn. — Could complex beliefs like paranoia have roots in something as basic as vision? A new Yale study finds evidence that they might.

When completing a visual perception task, in which participants had to identify whether one moving dot was chasing another moving dot, those with greater tendencies toward paranoid thinking (believing others intend them harm) and teleological thinking (ascribing excessive meaning and purpose to events) performed worse than their counterparts, the study found. Those individuals more often — and confidently — claimed one dot was chasing the other when it wasn’t.

The findings, published Dec. 17 in the journal Communications Psychology, suggest that, in the future, testing for illnesses like schizophrenia could be done with a simple eye test.

“We’re really interested in how the mind is organized,” said senior author Philip Corlett, an associate professor of psychiatry at Yale School of Medicine and member of the Wu Tsai Institute. “Chasing or other intentional behaviors are what you might think of as experiences perceived at a very high-level in the brain, that someone might have to reason through and deliberate. In this study, we can see them low down in the brain, in vision, which we think is exciting and interesting — and has implications for how those mechanisms might be relevant for schizophrenia.”

Paranoia and teleological thinking are similar in that they are both misattributions of intention, but paranoia is a negative perception while teleological thinking tends to be positive. Both patterns of thinking are linked to psychosis and schizophrenia.

Hallucinations are associated with psychosis as well and are often about other people, said Corlett, suggesting there may be a social component to these visual misperceptions.

“So we wondered whether there might be something related to social perception — or misperception, what we refer to as social hallucination — that we could measure and that relate to these symptoms of psychosis,” he said.

For the task, participants were shown dots moving on a screen. Sometimes one dot was chasing another; other times there was no chase. Across different trials of the task, participants had to say whether a chase was occurring or not.

Those with higher degrees of paranoia and teleological thinking (as measured through questionnaires) were more likely than others to say with confidence that a chase was happening when one wasn’t. Essentially, they perceived a social interaction that wasn’t occurring.

In additional experiments, the researchers asked participants to identify which dot was doing the chasing and which dot was being chased. In these results, paranoia and teleological thinking began to diverge.

“People with paranoia were particularly bad at detecting which dot was being chased,” said Santiago Castiello, lead author of the study and a postdoctoral researcher in Corlett’s lab. “And people with high teleology were particularly bad at detecting which dot was doing the chasing.”

That these two types of beliefs differed in this way highlights that they are distinct and may have implications for diagnosis or treatment, said the researchers. The connection to vision may also shift thinking around how the brain gives rise to psychotic symptoms.

“Very few people with congenital blindness develop schizophrenia,” said Castiello. “Finding these social hallucinations in vision makes me wonder if schizophrenia is something that develops through errors in how people sample the visual world.”

While there are no immediate therapeutic implications from these findings, deeper understanding of these beliefs could aid in pharmacological treatment development and risk assessment.

“One thing we’re thinking about now is whether we can find eye tests that predict someone’s risk for psychosis,” said Corlett. “Maybe there is some very quick perceptual task that can identify when someone might need to talk to a clinician.”

 

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Disclaimer: AAAS and EurekAlert! 

WOMYN'S HEALTH

Women often told that severity of medical abortion pain no worse than period cramps

Many women unprepared for pain intensity; more realistic info needed to inform choice



BMJ Group




Women opting for a medical abortion at home are often advised that the procedure is likely to be no more painful than period cramps, suggest the results of a survey, carried out by the British Pregnancy Advisory Service (BPAS), and published online in the journal BMJ Sexual & Reproductive Health.

 

This leaves many women unprepared for the intensity of the pain they experience, with some survey respondents saying they would have chosen a different option, had they known.

More realistic and patient centred information needs to be provided to enable women to make an informed choice, says the author, noting that BPAS has already changed its approach in light of the findings.

Medical abortion is achieved with pills at up to 10 weeks. It can take place  at home and can be delivered by telemedicine without the need for a clinic appointment.

In England and Wales, it is the most common method up to 10 weeks of pregnancy, with nearly all such abortions carried out at home, explain the researchers. 

But medical abortion is often painful. And several previously published studies have highlighted the importance of anticipatory counselling about pain management, and the impact that good counselling can have on fear, anxiety, and the level of pain experienced, the researchers add.

To better understand the experience and expectation of pain, and how these might determine choice of abortion method, the researchers invited 11,906 BPAS clients who had had a medical abortion up to 10 weeks of pregnancy to fill in an online questionnaire between November 2021 and March 2022. 

They were asked about the pain they experienced, and how they would describe this to a friend; if they had to have another abortion, what their preferred method would be, and if this was influenced by the pain they experienced; and what advice they would like to have been given about what to expect.

In all, 1596 (13.5%) completed the questionnaire, and included at least one free-text comment. Most (85%) were between the ages of 20 and 39.

One in three of the clients (530) had pregnancies that were between 8 and 9 weeks and almost half had not given birth before (49%; 777).

About half (48.5%; 773) of respondents said that the pain they experienced was more than expected, with most (92%) giving their pain a score of at least 4 out of a maximum of 10. In all, 662 (41.5%) scored it 8-10 (severe).

While two thirds (1047) of respondents said they would choose a medical abortion if needed in future, around 1 in 8 (13%; 202) said they would have a surgical abortion. And most of them (83%; 167) cited pain as a factor in this decision.

Those who opted for a surgical abortion if needed in the future reported an average maximum pain score of 8.5 compared with a score of just over 6 for those opting for a medical abortion if needed in the future.

Some respondents felt the pain they experienced was no worse than period pain, but others felt unprepared for the level of pain they experienced, which they attributed to being advised that it was comparable to period pain, as well as a lack of detailed, realistic anticipatory pain counselling. 

One respondent said: “Pain was so much stronger than period pain, it was like having contractions in labour. I've given birth three times and the pain really wasn't too much different from that pain, the cramping contraction pain.” 

Others said the pain they experienced was far greater than expected, with some directly attributing this to language or detail given to pain in consultations or information leaflets as being “washed over”, “downplayed,” or “sugar-coated.”

A substantial number of respondents said that descriptions of medical abortion pain as period-like (for example, “like a period”, or “a bad period”, “period cramps” or “period cramping”) had played directly into their expectations.

One respondent commented: “[Being transparent] might put some women off from abortion,  however, I feel that patients have a right to fully understand the risks and benefits. This should be made absolutely transparent; shared and informed decision making is essential.”

“Providing accurate, realistic information on pain is not only important for preparing patients for medical abortion, but for supporting informed consent for abortion method choice, in the context of structural constraints,” write the researchers.

They acknowledge the potential for misremembering pain intensity among respondents, but say the findings have already changed the information BPAS provides on what to expect if clients choose a medical abortion.

“Patients want detailed, realistic anticipatory pain counselling as well as general preparatory advice, including first-hand experiences which reference a wide and accessible range of descriptions of pain,” they conclude.

*Lead author, Hannah McCulloch, comments: “Benchmarking against period pain has long been used as a way to describe the pain associated with medical abortion, despite the wide variability of period pain experienced.

“The results of the survey show that counselling on this aspect of medical abortion needs to improve. For many respondents, using period pain as a reference point for what to expect was not helpful for managing expectations, or in line with their experiences.

“Women want more detailed, realistic information to make choices about treatment and to be prepared for medical abortion if that is their preference. And medical abortion is a very safe and effective choice. This evaluation led us at BPAS to create new patient materials and provide additional staff training, which we are currently in the process of evaluating.”

 

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Nonheterosexual women may maintain better sexual functioning during menopause transition



New study suggests that midlife nonheterosexual women are more likely to remain sexually active and less likely to report pain during sexual activity than heterosexual women


The Menopause Society





CLEVELAND, Ohio (Dec 18, 2024)–A woman’s sex drive may diminish with age—partially because of problems with genitourinary symptoms during the menopause transition. Yet, some older women maintain very active sex lives. Why? A new study suggests that one difference could be sexual identity, with nonheterosexual women more likely to report better sexual functioning, despite menopause. Results of the study are published online today in Menopause, the journal of The Menopause Society.

An estimated 25% to 85% of postmenopausal women report challenges with sexual function, including pain with sex, difficulty with desire or libido, and distress concerning their sexual response. These symptoms often emerge during the menopause transition and can be chronic and progressive, with lasting implications for quality of life and sexual well-being.

Nonheterosexual women (also known as sexual minority women) typically experience worse mental and physical health because of the barriers and discrimination they face when engaging with the healthcare system. However, according to a new study involving more than 230 female Veterans, when it comes to sexual function, nonheterosexual women may fare better. Although they still report high levels of distress related to sexual function—similar to their heterosexual counterparts—they report better sexual functioning and less effect of vaginal symptoms.

Female Veterans represent a growing, diverse population for researching because the number of women enrolled in healthcare through the Veterans Health Administration (VHA) has more than doubled over the last two decades. Moreover, over half of the women served by the VHA are in midlife (typically aged between their 40s and 60s)—a critical window for health changes related to the menopause transition.

Despite the growing number of research studies conducted relative to challenges of the menopause transition, there is a lack of systematic research investigating menopause- and age-related experiences for nonheterosexual women. That’s what prompted researchers to conduct this latest study that found that nonheterosexual women were more than two-fold more likely to report past-month sexual activity and less likely to report pain during sexual activity.

Survey results are published in the article “Sexual orientation and sexual functioning in midlife women veterans.”

“The results of this study highlight that menopause and aging substantively affect sexual health and functioning in women Veterans and, further, that experiences may vary significantly based on sexual identity. Additional research is needed to better understand the unique needs of midlife sexual minority women and to promote the provision of affirming healthcare to sexual minority women Veterans,” says Dr. Stephanie Faubion, medical director for The Menopause Society.

For more information about menopause and healthy aging, visit www.menopause.org.

The Menopause Society (formerly The North American Menopause Society) is dedicated to empowering healthcare professionals and providing them with the tools and resources to improve the health of women during the menopause transition and beyond. As the leading authority on menopause since 1989, the nonprofit, multidisciplinary organization serves as the independent, evidence-based resource for healthcare professionals, researchers, the media, and the public and leads the conversation about improving women’s health and healthcare experiences. To learn more, visit menopause.org.

WOKE BONOBO'S

World’s only bonobo sanctuary helps orphaned apes overcome trauma to develop social skills and empathy




Durham University
Bonobos research 1 S.Kordon 

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Two bonobos in friendly social contact.

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Credit: Stephanie Kordon/Lola ya Bonobo Sanctuary




Apes orphaned by the illegal trade in bushmeat and pets can overcome trauma and develop social abilities like those of their mother-reared peers.

A new study led by Durham University, UK, looked at the effects of rehabilitation by the world’s only bonobo sanctuary on the social and emotional development of orphaned bonobo apes across a 10-year period.

Bonobos are our closest living relatives, along with chimpanzees, and are only found in the Democratic Republic of Congo. The early life trauma of maternal loss and the deprivation from being captured by humans can have long lasting negative effects on bonobos’ social abilities.

Researchers wanted to see what impact rehabilitation in the Congolese sanctuary of Lola ya Bonobo had on the social and emotional skills of orphaned bonobos, compared to those who were raised by their mothers, at different points in time across the animals’ lifespans.

In particular, the researchers investigated how the bonobos’ empathy, social skills and aggression behaviours developed across their lifespan, as well as between the sexes.

Although the orphaned bonobos studied showed reduced social skills, they still demonstrated a degree of the species-typical social behaviours seen in the mother-reared apes.

The researchers say this underscores the orphans’ ability to overcome challenges as well as the important role that rehabilitation centres like this can play in their recovery before the apes are released back into the wild.

The findings are published in the journal Royal Society Open Science.

Lead author Stephanie Kordon, a PhD researcher in the Department of Psychology, Durham University, said: “Bonobos are one of our closest ape cousins, but they are in danger of extinction due to logging and the illegal trade in bushmeat and pets.

“The Lola ya Bonobo sanctuary does vital work in protecting this vulnerable species. While the orphans’ social development is not equivalent to that of their mother-reared counterparts, they overlap in the development and behaviours they display.

“By better understanding the healthy social development of bonobos, we aim to help the important rehabilitation and conservation efforts of this unique species.”

In total researchers observed 83 bonobos at different points in their lives across 10 years at Lola ya Bonobo.

The researchers saw that social skills increased in female bonobos and decreased in males with age, which is consistent with how bonobos interact in the wild, as bonobos are a female-led society. However, these skills were lower in orphans compared to those who were mother-reared.

While orphaned bonobos were consistently less likely to show empathy – such as comforting another bonobo – this ability was not completely absent. This suggests that orphans continue to demonstrate care towards other bonobos, even if it is at a lower end of the scale.

The fact that orphans’ tendency to console others was still within the range of mother-reared bonobos – although at a lower level – also suggests they may have sufficient skills to cope within social groups. This is important as some of these apes go on to be reintroduced back into the wild, where social skills are critical for survival.

Mother-reared and older females were more likely to be aggressive to other group members, while young and male bonobos were more likely to be the victims of aggression. However, how bonobos were reared did not predict their risk of being a victim of aggression.

Research senior-author Professor Zanna Clay, Department of Psychology, Durham University, said: “While we cannot say the orphaned bonobos are absolutely rehabilitated, our findings do show a good direction to their social function as we are seeing them demonstrate species-typical behaviours within low but normal ranges.

“Comparing orphans with mother-reared bonobos also gives us a fascinating insight into how early life experiences can influence the development of social and emotional skills in our closest cousins and the importance of sanctuaries in supporting that development.”

The research also included researchers from Harvard University and Emory University, both USA.

It was funded by the Templeton World Charity Foundation: Diverse Intelligences initiative and a European Research Council Horizon 2020 Starting Grant.

ENDS

Social play behaviour between an orphaned and a mother-reared juvenile bonobo.