How the intestine replaces and repairs itself

Peer-Reviewed Publication

ROCKEFELLER UNIVERSITY

 

IMAGE: A SIDE VIEW OF THE SMALL INTESTINE WITH LYMPHATIC CAPILLARIES IN YELLOW AND INTESTINAL STEM CELLS IN PINK. view more 

CREDIT: ROBIN CHEMERS NEUSTEIN LABORATORY OF MAMMALIAN CELL BIOLOGY AND DEVELOPMENT AT THE ROCKEFELLER UNIVERSITY

To act as a robust barrier against pathogens while also absorbing needed nutrients, the lining of the intestines must regenerate on a daily basis to remain equal to the task. The intestine’s resident stem cells are responsible for meeting this need for constant repair and replenishment, but each stem cell faces decisions that depend on the overall conditions of the intestine and the needs of the moment. Bad decisions and poor coordination could result in intestinal diseases or cancer.

A new study suggests that stem cells are able to integrate cues from their surroundings and coordinate their behavior across the tissue through networks of vasculature in their close vicinity.

Rockefeller scientists found that lymphatic capillaries—fine vessels that transport immune cells and drain fluids from tissues—represent a signaling hub that communicates with stem cells to regulate their activity. With molecular guidance from the lymphatics, the stem cells produce daughter cells to repopulate the intestinal lining or self-renew to restock the stem cell reserve.

The findings, published in the journal Cell Stem Cell, provide new insights about primary intestinal components whose disrupted communication may contribute to intestinal disorders, such as inflammatory bowel disease. “The key to treating these diseases will be to figure out who talks to whom in this ecosystem and how we can reset the communication networks,” says Rachel Niec, a clinical scholar in the laboratory of Elaine Fuchs.

Communications in the crypt

The intestinal stem cells reside in so-called crypts, found at the base of densely packed indentations in the intestinal lining. The stem cells may renew and stay in the crypt, or differentiate into specialized cells, which then migrate out of the crypt to replenish the gut lining. “To understand how stem cells balance self-renewal with differentiation, we needed a more complete picture of crypt niches,” says Marina Schernthanner, a graduate student in the Fuchs lab.

To zoom in on the crypt, the team used a suite of techniques, including single-cell and spatial transcriptomics, which allowed them to identify cell types at specific locations and study their signaling molecules. The results showed that lymphatic capillaries, which form an intimate connection with the stem cells in the crypt, produce a number of proteins known to be important for stem cell functioning.

One previously underappreciated protein, REELIN, emerged as a top candidate for mediating communications between lymphatics and stem cells. By manipulating the amount of REELIN in lab-grown intestinal organoid cultures in some experiments and genetically suppressing it in mice in others, the researchers found that REELIN directly governs the regenerative behavior of intestinal stem cells.

The involvement of the lymphatic system in stem cell functioning is a relatively new concept. A previous study by the Fuchs team revealed that lymphatics are also closely involved with stem cells of the skin and play a key role in hair regeneration. There, however, it is the hair follicle stem cells that signal to lymphatic capillaries. By controlling their interactions with lymphatics, the stem cells synchronize hair regeneration across the tissue. “This suggests that lymphatics may be a conserved feature of stem cell niches, but their relationship to stem cells are likely tailored around the needs of each tissue,” Niec says.

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JOURNAL

Cell Stem Cell

DOI

10.1016/j.stem.2022.05.007 

HKUST researchers developed nanoporous zinc electrodes that make primary alkaline zinc batteries rechargeable

Peer-Reviewed Publication

HONG KONG UNIVERSITY OF SCIENCE AND TECHNOLOGY

 

IMAGE: (FROM LEFT) PROF. CHEN QING AND HIS RESEARCH GROUP MEMBERS DR. LI LIANGYU (POSTDOCTORAL FELLOW) AND XIAO DIWEN (PHD STUDENT) AT THE LAB OF HKUST ENERGY INSTITUTE. ON THE LAB BENCH IS A SET-UP FOR FABRICATING THE NANOPOROUS ZINC METAL ELECTRODE. view more 

CREDIT: HKUST

A research team at The Hong Kong University of Science and Technology (HKUST) has developed a new electrode design that is set to enable the rechargeability of alkaline zinc batteries, one of the most common types of non-rechargeable batteries used in our daily lives, shedding light on a wider application of rechargeable batteries.

Batteries are ever important in the age of smart cities and global digitalization. Yet, a majority of batteries in the market are not rechargeable, or called primary batteries. They are disposed after a single use, an unsustainable practice that poses a serious threat to the environment.

Compared with other types of primary batteries, alkaline zinc batteries are cheap, safe, and energy-dense. They are used in many household items such as flashlights and remote controllers.  Given the advantages, there is never a lack of effort from researchers worldwide trying to make alkaline zinc batteries rechargeable. 

Yet, such effort has been falling short because the battery reaction of zinc is hardly reversible. When the battery is discharged, zinc particles in the zinc electrode are covered with a thick and non-uniform layer of insulating zinc oxide, losing the metal surface and electric conductivity, both necessary for the electrode to be recharged. 

To tackle the issue, a research team led by Prof. CHEN Qing from the Department of Mechanical & Aerospace Engineering and Department of Chemistry at HKUST developed a nanoporous zinc metal electrode that is capable of stabilizing the electrochemical transition between zinc and zinc oxide, successfully turning an alkaline zinc-air coin cell, a type of primary battery usually found in hearing aids, into a rechargeable battery stable for over 80 hours. The team shaped zinc into curvy filaments hundreds of nanometers wide, nested in a freestanding solid with numerous, similarly narrow pores. When the battery is discharged, a thin layer of zinc oxide nucleates on the zinc filaments, preserving the metallic network and enabling the zinc electrode to return to its initial structure.

The team also tested out the nanoporous zinc electrode in alkaline nickel-zinc batteries, a kind of uncommon secondary zinc battery which normally offer 50-80 times of discharging and charging under a condition competitive against the state-of-the-art lithium-ion batteries. The result demonstrated a multi-fold increase to over 200 times. 

“The needs for batteries are diverse and difficult to be met by a single technology. Zinc batteries are finding their niche. We just need to make sure that the microstructure of the zinc electrodes can withstand hundreds, and hopefully thousands, of times of discharging and charging when getting the most energy out of the batteries,” said Prof. Chen. “Our work achieves so by understanding and then designing how atoms organize themselves at the liquid-solid interface that is manifested by the nanoporous structure, which has been applied to address a range of technological challenges,” he explained.

Prof. Chen added that while a few hundred times of discharging and charging may not seem many, alkaline zinc batteries have an edge in safety and low cost, which are ideal for industrial applications such as golf carts and forklifts. They also suit emerging applications, for example, the backup power of data centers, which do not demand many times of discharging and charging but require the battery to be extremely safe. 

Prof. Chen’s group has been working with industrial partners since the beginning of the research in 2018 and will continue engaging them for the commercialization of the promising technologies.

The team’s research work was recently published in Nature Communications.

Led by Prof. Chen, the team included postdoctoral fellow Dr. LI Liangyu, former research assistant Anson TSANG Yung-Chak, PhD student XIAO Diwen, former postdoctoral fellow Dr. ZHU Guoyin, as well as Prof. ZHI Chunyi from the City University of Hong Kong.

CAPTION

A 3D model of the nanoporous structure in the zinc electrode, magnified by 10,000 times for the visualization.

CREDIT

HKUS

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JOURNAL

Nature Communications

DOI

10.1038/s41467-022-30616-w 

ARTICLE TITLE

Phase-transition tailored nanoporous zinc metal electrodes for rechargeable alkaline zinc-nickel oxide hydroxide and zinc-air batteries

Sustainable practices linked to farm size in organic farming

Peer-Reviewed Publication

CORNELL UNIVERSITY

ITHACA, N.Y. – Larger organic farms operate more like conventional farms and use fewer sustainable practices than smaller organic farms, according to a new Cornell University study that also provides insight into how to increase adoption of sustainable practices.

“We wanted to look at how the practices differ between small-scale organic farms like the ones you see scattered around the Finger Lakes, which may serve the local farmer’s market, and those huge farms that supply organic produce to big box stores,” said Jeffrey Liebert, who studied agroecology at the School of Integrative Plant Science, Soil and Crop Sciences Section, in the College of Agriculture and Life Sciences. “I visited numerous large farms where their organic acreage was on one side of the road and their conventional acreage on the other side, and you couldn’t tell the difference.”

Liebert is first author of “Farm Size Affects the Use of Agroecological Practices on Organic Farms in the United States,” published July 21 in Nature Plants.

He and an interdisciplinary group of researchers from Cornell, U.C. Berkeley, and The Nature Conservancy surveyed 542 organic fruit and vegetable farmers about the use of eight agroecological practices – those that improve sustainability by leveraging ecological processes and providing ecosystem services. They also looked at indicators of ‘conventionalization’ in organic farming, such as reduced crop diversity, mechanization and a focus on high volume and wholesale production.

They found that, on average, the larger farms used fewer agroecological practices and that organic farming on large farms more closely resembled conventional farming, with growers often substituting synthetic pesticides and fertilizers with inputs permitted in organic production, rather than redesigning their farms to integrate a broader suite of sustainable agroecological practices.

U.S. organic fruit and vegetable sales represent 15% of all retail produce sales, and organic food sales total nearly $57 billion a year. While large farms in the organic market could drive prices down and expand access, the use of fewer agroecological practices and greater degree of conventionalization could reduce the sustainability of organic agriculture and confidence in the organic label, the authors said.

“This conventionalization of organic farming is a real issue,” said Matthew Ryan, associate professor in the School of Integrative Plant Science and co-author of the paper. “If it goes too far, then consumer confidence in the organic label will dissipate, you lose that price premium, people won’t be using these practices – and we’ll lose those ecosystem services and benefits.”

The researchers found that larger farms were more likely to use agroecological practices that primarily increased efficiency. For example, reduced tillage, which minimizes disturbance to soil but also requires specialized equipment, was more common on larger farms. Smaller farms were more likely to use non-crop vegetation; for example, they were almost three times more likely than large farms to use insectary plantings, which attract beneficial insects.

There are a number of reasons large farms might not adopt agroecological practices, Liebert said. Insectary plantings on the perimeter of a very large field (versus a small field) might not be as effective for pollination, for example. In California, a program to incentivize the planting of hedgerows – which provide habitat for wildlife and beneficial insects – went south when food safety scares spooked large supermarket retailers; without adequate empirical evidence, farmers had to weigh the perceived risk of crop contamination from wildlife with the ecological and agricultural benefits. As a result, some farmers removed their hedgerows in order to keep their contracts with powerful wholesale buyers.

“This was a good example of how we can’t solve some of these issues around sustainability or biodiversity if you’re not taking a more interdisciplinary approach,” Liebert said. “If we’re not engaging in conversations with policymakers and the private sector, which has such a strong influence on the practices farmers are using, we won’t be successful in promoting the adoption of these practices.”

More research about how to scale up agroecological practices for large farms is needed, and the authors recommend tailoring incentive programs to large-, medium- and small-scale farmers. For example, programs could provide greater rewards to large farms that redesign – rather than simply substitute – elements of their management to incorporate agroecological practices.

The authors also recommend measures to protect small- and medium-size farms from the competition posed by large-scale organic farms. An additional finding of the survey was that, contrary to previous assumptions, small-scale organic farmers do feel competition from large farms, despite serving different markets.

“If we can help those medium- or small-sized farms gain access to alternative markets, and develop value-added products that lie outside the scope of direct competition with large farms, that could be impactful,” Liebert said.

Cornell co-authors include: Rachel Bezner Kerr, professor of global development; Thomas Björkman, professor in the School of Integrative Plant Science; Miguel Gómez, the Robert G. Tobin Food Marketing Professor in the Charles H. Dyson School of Applied Economics and Management and professor in the Department of Global Development, all in CALS; and Alison Power, professor of ecology and evolutionary biology in the College of Arts and Sciences. Support for the research came from the Cornell Atkinson Center for Sustainability.

For additional information, see this Cornell Chronicle story.

-30-

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JOURNAL

Nature Plants

DOI

10.1038/s41477-022-01191-1 

ARTICLE TITLE

Farm size affects the use of agroecological practices on organic farms in the United States

COVID-19 may have increased UK doctors’ willingness to not resuscitate the very sick/frail

But it hasn’t altered their views on euthanasia and assisted dying, snapshot survey suggests

Peer-Reviewed Publication

BMJ

COVID-19 may have changed UK doctors’ end of life decision-making, making them more willing to not resuscitate very sick and/or frail patients and raising the threshold for referral to intensive care, suggest the results of a snapshot survey published online in the Journal of Medical Ethics.

But the pandemic hasn’t altered their views on euthanasia and physician assisted dying, with around a third of respondents still strongly opposed to these policies, the responses show.

The COVID-19 pandemic transformed many aspects of clinical medicine, including end of life care, prompted by thousands more patients than usual requiring it, say the researchers. 

They therefore wanted to find out if it has significantly changed the way in which doctors make end of life decisions, specifically in respect of ‘Do Not Attempt Cardio-Pulmonary Resuscitation’ (DNACPR) and treatment escalation to intensive care.

The researchers chose these aspects of end of life care, because of the controversy surrounding  DNACPR decisions, partly prompted by an increase in cardiac arrests associated with COVID-19 infections, and concerns about intensive care capacity, sparked by soaring demand during the pandemic. 

The researchers also wanted to know if the pandemic had changed doctors’ views on euthanasia and physician assisted suicide as surveys on these issues by the British Medical Association (BMA) and the Royal Colleges of Physicians and General Practitioners had been carried out before it started.

The online survey was open to doctors of all grades and specialties between May and August 2021, when hospital admissions for COVID-19 in the UK were relatively low.

In all, 231 responses were received: 15 from foundation year 1 junior doctors (6.5%); 146 from senior junior doctors (SHOs) (63%); 42 from hospital specialty trainees or equivalent (18%); 24 from consultants or GPs (10.5%); and 4 others (2%).

In respect of DNACPR, which refers to the decision not to attempt to restart a patient’s heart when it or breathing stops, over half the respondents were more willing to do this than they had been previously.

When the responses were weighted to represent the different medical grades in the NHS national workforce, the results were: ‘significantly less’ 0%; ‘somewhat less’ 2%; ‘same or unsure’ 35%; ‘somewhat more’ 41.5%; ‘significantly more’ 13%; and ‘not applicable’ 8.5%.

When asked about the contributory factors, the most frequently cited were: ‘likely futility of CPR’ (88% pre-pandemic, 91% now): co-existing conditions (89% both pre-pandemic and now): and patient wishes (83.5% pre-pandemic, 80.5% now). Advance care plans and ‘quality of life’ after resuscitation also received large vote-share.

The number of respondents who stated that ‘patient age’ was a major factor informing their decision increased from 50.5% pre-pandemic to around 60%. And the proportion who cited a patient’s frailty rose by 15% from 58% pre-pandemic to 73%. 

But the biggest change in vote-share was ‘resource limitation’, which increased by 20%, from 2.5% to 22.5%. 

When asked whether the thresholds for escalating patients to intensive care or providing palliative care had changed, the largest vote-share was the ‘same or unsure’: 46% (weighted) for referral; 64.5% (weighted) for palliative care.

But a substantial minority said that now they had a higher threshold for referral to intensive care (22.5% weighted) and a lower threshold for palliation (18.5% weighted).

When it came to the legalisation of euthanasia and physician assisted suicide, the responses showed that the pandemic has led to marginal, but not statistically significant, changes of opinion.

Nearly half (48%) were strongly or somewhat opposed to the legalisation of euthanasia, 20% were neutral or unsure, and around a third were somewhat or strongly in favour before the pandemic. These proportions changed to 47%, 18%, and 35%, respectively. 

Similarly, just over half (51%) said they had strongly or somewhat opposed the legalisation of physician assisted suicide, 24% had been neutral or unsure, and 25% had been somewhat or strongly in favour.  These proportions changed to 52%, 22%, and 26%, respectively. 

The impetus to make more patients DNACPR, prompted by pressures of the pandemic, persisted among many clinicians even when COVID-19 hospital cases had returned to relatively low levels, note the researchers. The factors informing it were compatible with regulatory (GMC) ethical guidance—with the exception of limited resources.

“At the start of the pandemic, the BMA advised clinicians that in the event of NHS resources becoming unable to meet demand, resource allocation decisions should follow a utilitarian ethic.

“However, what is clear from our results is that for a significant proportion of clinicians, resource limitation continued to factor into clinical decision making even when pressures on NHS resources had returned to near-normal levels,” they write.

The survey results also suggest that the pandemic has helped clinicians gain a greater understanding of the risks, burdens, and limitations of intensive care and had further educated them in the early recognition of dying patients, and the value of early palliative care, they add. 

“What is yet to be determined is whether these changes will now stay the same indefinitely, revert back to pre-pandemic practices, or evolve even further,” they conclude.

Notes for editors
Research: How is COVID-19 changing the ways doctors make end-of-life decisions? Doi: 10.1136/medethics-2022-108268

Journal: Journal of Medical Ethics

Funding: None declared
Link to Academy of Medical Sciences press release labelling system: http://press.psprings.co.uk/AMSlabels.pdf

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JOURNAL

Journal of Medical Ethics

DOI

10.1136/medethics-2022-108268 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

How is COVID-19 changing the ways doctors make end-of-life decisions?

ARTICLE PUBLICATION DATE

25-Jul-2022

Unhealthy food and beverage brands encouraging TikTok users to market their products for them

Given TikTok’s popularity with children, policies are needed to protect them, say researchers

Peer-Reviewed Publication

BMJ

Unhealthy food and beverage brands are encouraging TikTok users to market their products for them—effectively turning them into ‘brand ambassadors’—as well as using their own accounts for promotional activity, finds an assessment of video content posted on the social media platform and published in the open access journal BMJ Global Health.

Given TikTok’s popularity with children, the findings emphasise the need for policies that will protect them from the harmful impact of this type of marketing on social media, insist the researchers.

Children are exposed to a vast amount of unhealthy—high in salt, sugar, and fat—food marketing online, say the researchers. And the evidence shows that this exposure ultimately influences food preferences, purchasing, requests and consumption.

TikTok users create, post, watch and engage with short videos. Since its global release, TikTok’s popularity has rapidly increased: its global monthly active users reportedly rose from 55 million in January 2018 to one billion in September 2021.

And it is popular with children: over a third of its daily users in the USA are reportedly aged 14 or younger.

Yet no study to date has looked at the impact of unhealthy food marketing on TikTok, despite calls for attention to be paid to the health implications of the platform, say the researchers.

In a bid to plug this knowledge gap, the researchers assessed the content of all videos posted on the accounts of 16 leading food and non-alcoholic beverage brands—based on global brand share as of 30 June 2021. 

The content and sentiment of a sample of relevant user-generated content, created in response to branded hashtag challenges instigated by these brands, was also assessed.

Some 539 videos had been posted on the 16 included accounts, with 3% (17) posted in 2019 (earliest year of posting), 37% (198) in 2020, and 60% (324) in the first 6 months of 2021. Four accounts had not posted any videos. 

The number of followers of the included accounts ranged from 14 to 1.6 million. Videos received an average of 63,400 views, 5829 likes, 157 comments and 36 shares per video.

The most common marketing strategies were branding (87% of videos), product images (85%), engagement (31%), and celebrities/ influencers (25%). 

Engagement included instigation of branded hashtag challenges that encouraged creation of user-generated content featuring brands’ products, videos, and/or branded effects, such as stickers, filters, or special effects featuring branding. 

The total collective views of user-generated content from single challenges ranged from 12.7 million to 107.9 billion. Among a sample of 626 brand-relevant videos generated in response to these challenges, 96% featured branding, 68% product images, and 41% branded effects. 

Most portrayed a positive (73%) or neutral/unclear (25%) sentiment, with few portraying a negative (3%) sentiment.

This is an observational study, so can’t establish causality. And the researchers acknowledge that the sampled user-generated content may not have been representative of a branded hashtag challenge. Nor were they able to measure children’s exposure to brands’ promotional activities or to user-generated content.

But they note: “Brand activity has rapidly increased—with most videos posted in the 6 months preceding data collection—and includes instigation of branded hashtag challenges that encourage user-generated content featuring brand products, brand-supplied videos or branded effects.

“Analysis of a sample of brand-relevant user-generated content created in response to these showed that branded hashtag challenges are effectively turning users into, in TikTok’s words, ‘unofficial brand ambassadors’.”

While fewer videos were posted by users who seem to have been paid (influencers, for example), these attracted nearly 10 times as many likes per video, on average, as those seemingly not paid for, and are therefore likely important in propagating branded hashtag challenges, they point out. 

“The substantial reach of influencer marketing is concerning given that exposure to influencer marketing of unhealthy foods has been shown to increase energy intake (from unhealthy foods and overall),” they write.

And they highlight that proposed UK legislation will ban all ‘paid-for’ online marketing of ‘less healthy food and drink’ from January 2023. But it includes an exemption for brand-only advertising, and excludes marketing originating outside the UK, despite the fact that social networking platforms frequently operate across international borders. 

They conclude: “Our study has shown that TikTok is an emerging source of unhealthy food marketing, including that created by users at the instigation of brands. Given TikTok’s popularity among children, our findings support the need for policies that protect children from the harmful impact of food marketing, including that on social networking platforms. 

“TikTok’s rising popularity also calls for further research into its potential impact on public health and its role as a corporate political actor.”

Notes for editors:

Research: Turning users into ‘unofficial brand ambassadors’: marketing of unhealthy food and non-alcoholic beverages on TikTok doi 10.1136/bmjgh-2022-009112
Journal: BMJ Global Health

Funding: None declared

Link to Academy of Medical Sciences press release labelling system http://press.psprings.co.uk/AMSlabels.pdf

Embargoed link to article
http://press.psprings.co.uk/gh/july/bmjgh009112.pdf

Public link once embargo lifts
https://globalhealth.bmj.com/lookup/doi/10.1136/bmjgh-2022-009112

 

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JOURNAL

BMJ Global Health

DOI

10.1136/bmjgh-2022-009112 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Turning users into ‘unofficial brand ambassadors’: marketing of unhealthy food and non-alcoholic beverages on TikTok

ARTICLE PUBLICATION DATE

25-Jul-2022

To tax or not to tax, is that even a question?

Resolving issues related to tax efficiency assessments

Peer-Reviewed Publication

KYOTO UNIVERSITY

 

IMAGE: CONSUMER AND PRODUCER SURPLUSES BOTH FRAME THE DYNAMIC RELATIONSHIPS DESCRIBING THE UNIVERSAL IMPACT OF TAX CHANGES. view more 

CREDIT: KYOTOU/TAKANORI ADACHI

Kyoto, Japan -- Robin Hood would not even have had to become an outlaw if the markets had been more competitive and Nottingham's taxation office had known how to assess taxes efficiently.

Today's financial world may not require a savior dressed in green, but it remains to be seen whether there is a need to reflect on checks and balances in examining invisible loss assessment.

Now, a researcher at Kyoto University and his collaborator are proposing a solution with an analytical framework for evaluating tax efficiency, mainly in the context of consumption taxes on goods. Consumer surplus and producer surplus -- together, social surplus -- both frame the dynamic relationships that describe the impact of tax changes on social welfare in tangible and intangible ways.

"This impact constitutes the invisible burden, manifested as behavioral constraints imposed by taxation on producers and consumers, added to the visible burden of the actual amount taxed," explains lead author Takanori Adachi.

The team has derived a formula expressing the marginal cost of public funds, essentially a ratio of a net loss in social surplus to a net increase in tax revenue.

"We derived this formula from only a few indices, common across specific market demand conditions and cost factors, that clearly tell us how the degree of tax-driven social burden relates to imperfect competition," the author adds.

The team has derived a second formula, termed the incidence, to express the decrease in consumer benefits relative to net decrease in producer profits. This formula relies on the same indices as the first formula, helping to describe the general state of consumer confidence and perhaps hinting at economic forecasts.

"Our theoretical framework focuses on a single market for a deeper study of how the socio- economic factors interrelate," says Adachi.

"Initially surprising but natural in hindsight is our finding that the assessment formulas reflect only the indices related to demand and cost structures plus the mode of competition."

###

The paper "Pass-Through, Welfare, and Incidence under Imperfect Competition" appeared on 3 June 2022 in Journal of Public Economics, with doi: 10.1016/j.jpubeco.2021.104589

About Kyoto University

Kyoto University is one of Japan and Asia's premier research institutions, founded in 1897 and responsible for producing numerous Nobel laureates and winners of other prestigious international prizes. A broad curriculum across the arts and sciences at both undergraduate and graduate levels is

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JOURNAL

Journal of Public Economics

DOI

10.1016/j.jpubeco.2021.104589 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Pass-Through, Welfare, and Incidence under Imperfect Competition

Study confirms ED cases spike after Australian bushfires

Peer-Reviewed Publication

CURTIN UNIVERSITY

New research has – for the first time – found a direct link between people’s exposure to bushfire smoke and visits to Perth’s metropolitan emergency departments within days.

As part of research led by the Department of Health, Curtin University and Murdoch University, researchers examined more than 1.54 million emergency department admissions between 2015 and 2017 to assess the immediate impact of a person’s exposure to bushfire smoke over four days.

Lead author Senior Research Fellow Dr Adeleh Shirangi, from the Curtin School of Population Health, said total emergency department admissions and overall cardiovascular presentations increased by up to seven per cent when people were exposed to high levels of tiny toxic air pollutants created by bushfires.

“Bushfire smoke has significant and measurable impacts on human health and increases the number of patients seeking medical treatment in emergency departments. Pollutants from bushfires can affect air quality hundreds and even thousands of kilometres away from the site of the fire,” Dr Shirangi said.

“Air pollutants as tiny as three per cent the size of a human hair, known as PM2.5, are of particular concern as it can penetrate deep into the lungs and enter the bloodstream, leading to various cardiorespiratory problems. 

“This tiny air pollutant is most significantly elevated during Australian bushfire events, and its levels exceed the regulatory air quality standards, meaning it is extremely unsafe to inhale.”

Dr Shirangi said the results confirmed existing research that people aged 60 years and above, people with disadvantaged socioeconomic status and those with heart or lung problems were more susceptible to bushfire smoke.

“This study was the first of its kind to find a significant ‘dose-response’ relationship between a person’s exposure to elevated PM2.5 during bushfire events and their increased risk of ED admissions due to transient ischemic attacks (brief stroke-like attacks), with the most acute effects occurring in one (25 per cent increase) or two days (20 per cent increase) after exposure,” Dr Shirangi said.

“The percentage of people who attended emergency departments with acute lower respiratory tract infections also increased within one day (19 per cent increase) and three days (17 per cent increase) after their exposure to elevated PM2.5 during bushfires at high levels.”

An analysis of the global burden of disease due to outdoor air pollution estimated that PM2.5 caused about three per cent of mortality from heart and lung diseases. Australian studies show a five per cent increase in non-accidental deaths on days of high exposures to bushfire smoke.

“Long-term health effects from low-level exposures to toxic air particles remain a cause for concern. Long-term exposure is linked to impaired lung function, and even premature death,” Dr Shirangi said.

“Extreme fire weather has increased in Australia over the last 30 years due to climate change. We are experiencing more extreme heat events, an increase in severe fire danger days and a more extended fire season than ever before.

“Where safe to do so, people should stay indoors. A suitable face mask, such as the N95 mask known for its use during COVID19, should be worn outside or for those who are unavoidably exposed to bushfire smoke.”

Health advice on how to protect against the harms of exposure to smoke from landscape fires, including information for sensitive groups, and those with specific health conditions, can be found on the Department of Health’s website.

A collaborative research effort was made by the Epidemiology Branch at the Department of Health, Curtin University, Murdoch University, The University of Western Australia, the University of Tasmania, and the Western Australian Bureau of Meteorology, as well as NGIS who provided spatial technology data.

This research was funded by FrontierSI, formerly known as the Cooperative Research Centre for Spatial Information, and the WA Department of Health.

The full paper, titled ‘Exposure to fine particulate matter (PM2.5) during landscape fire events and the risk of cardiorespiratory emergency department attendances: a time-series study in Perth, Western Australia’, is available online here.

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JOURNAL

BMJ

DOI

10.1136/jech-2021-218229 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Study confirms ED cases spike after Australian bushfires

Supervolcano study finds CO2 emissions key to avoiding climate disasters

Peer-Reviewed Publication

CURTIN UNIVERSITY

The speed and volume of carbon dioxide emitted from supervolcanoes controlled the severity of past environmental crises on Earth, a new international Curtin-led study has found.

Lead researcher Dr Qiang Jiang, a Curtin PhD graduate from Curtin’s School of Earth and Planetary Sciences, said the findings were vital to understanding how to prevent future climate disasters.

“Earth’s biological cycle has been punctuated by catastrophic mass extinctions, some of which wiped out 90% of all species,” Dr Jiang said.

“The main culprit of these rapid environmental crises were massive volcanic eruptions. What had been puzzling scientists is that some of these gigantic eruptions resulted in severe extinctions, while others only resulted in minor environmental disturbances. We set out to discover why.

“An example of a less-deadly supervolcano is the Kerguelen large volcanic province- an enormous body of lava in the southern Indian Ocean three times the size of France. Its sheer area and volume makes it the second largest series of super volcanic eruptions since complex life began on Earth some 540 million years ago.

“Despite the enormous volumes of outpouring lava, it was not previously believed to be associated with any environmental catastrophe.”

Co-researcher Professor Fred Jourdan, Director of the Western Australian Argon Isotope Facility at Curtin University, said new experiments revealed that the Kerguelen province was linked to a comparatively minor global oceanic anoxic event, a time when large expanses of our oceans were depleted in oxygen.

“We used the argon-argon dating technique to date the Kerguelen lava flows, by analysing a series of black basaltic rocks drilled from the bottom of the sea floor,” Professor Jourdan said.

“The new age data revealed that the Kerguelen eruptions were, in fact, active right across the global oceanic anoxic event 120 million years ago. But while they may have rapidly degraded the environment for marine organisms, it did not lead to a deadly mass extinction.”

Co-author Dr Hugo Olierook, also from Curtin’s School of Earth and Planetary Sciences, said the amount and rate of carbon dioxide emitted by Kerguelen could explain why these enormous super volcanic eruptions made a comparatively small dent in our environmental and biological cycle.

“Other deadly supervolcanoes wiped out life primarily through rapid release of enormous volumes of carbon dioxide. Perhaps the Kerguelen eruptions emitted much slower or much less carbon dioxide, or both,” Dr Olierook said.

“We studied droplets of magma trapped within crystals in lava to investigate the amount and rate of CO2 released from the Kerguelen supervolcanoes and found they emitted at least five times less CO2 and at a rate 30 times slower than volcanic eruptions that wiped out entire lifeforms.

“Earth naturally has mechanisms by which carbon dioxide is taken out of our atmosphere and oceans and stored in rocks and soil, but these processes are gradual over hundreds of thousands of years and work only when the rate of emissions is moderate.

“However, alarmingly our calculations also show that we are now currently emitting carbon dioxide 200 times faster than those supervolcanic eruptions that caused the most severe mass extinctions.” 

Dr Jiang said these findings from the past could inform how we combat climate change now and in the future.

“Archives from the past clearly show that slowing down carbon dioxide emissions is crucial to mitigate Earth’s climate change and avoid potentially disastrous consequences that are projected based on current human-induced emissions.”

The research team includes researchers from Uppsala University in Sweden and the Commonwealth Scientific and Industrial Research Organisation in Perth.

The research paper, ‘Volume and rate of volcanic CO2 emissions governed the severity of past environmental crises’ was published in Proceedings of the National Academy of Sciences and can be found online here.

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JOURNAL

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2202039119 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Supervolcano study finds CO2 emissions key to avoiding climate disasters

ARTICLE PUBLICATION DATE

26-Jul-2022