COVID-19: Developing nations face different risks

by Melinda Knox, Queen's University

Susan Bartels, Professor in the Departments of Emergency Medicine and Public Health at Queen’s University, with her colleagues in the Democratic Republic of Congo during her earlier visit. Credit: Queen's University

As the novel coronavirus pandemic continues to impact countries worldwide, we've seen how nations around the world are working to mobilize populations, resources, and government assistance to mitigate spread of the virus and help those who have been affected. But how are developing nations impacted differently than developed nations in this crisis?

Susan Bartels, professor in the Departments of Emergency Medicine and Public Health at Queen's University, is an expert in global public health research that focuses on how people are affected by humanitarian crises, including armed conflict and natural disasters. Dr. Bartels was visiting South Africa for SSHRC-funded research investigating sexual exploitation and abuse by UN peacekeepers as well as Universities Canada-funded research examining parenting in settings of adversity. The Gazette spoke to Dr. Bartels, who recently returned from field research in the Democratic Republic of Congo (DRC), about how developing nations, such as DRC, are confronting unique challenges when it comes to COVID-19.

COVID-19 is being called a "global crisis." In what ways do you think it impacts developing nations differently than developed nations?

Susan Bartels: Lower- and middle-income countries like the Democratic Republic of Congo (DRC) are at an enormous disadvantage, due to lack of public health infrastructure, profoundly underfunded health care systems, and poor access to care. For example, although supplies and essential medical equipment are lacking in Canada, the Panzi Hospital in South Kivu province of the DRC has only 20 ventilators for its catchment population of more than 5.7 million people.

These countries are also significantly disadvantaged because government assistance programs will not be nearly as robust as they are in Canada (income support, tax deferrals, support for small business, etc.). Compounding that, in DRC, like in many other lower-income countries, chronic underlying illnesses such as HIV/AIDS, hepatitis, and tuberculosis (TB), as well as high rates of malnutrition among children, have the potential to dramatically increase COVID-related morbidity and mortality.

How are developing countries reacting to the pandemic?

SB: Eastern DRC has been responding to an Ebola epidemic since August 2018, so when it comes to screening, they were far more prepared than we were in Canada. For instance, when arriving to the Congo by air or by car, visitors were already subject to temperature screening in addition to a health questionnaire that had to be completed.


Additionally, social greetings had already been modified in the DRC. In response to the Ebola epidemic, hand shaking, hugging, and other forms of physical social greeting were no longer considered acceptable, and handwashing stations could be found outside all hospitals, clinics, shops, restaurants, hotels, and other public spaces. These screening and precautionary measures, which have already been in place for almost a year and a half, will now doubly serve to prevent transmission of COVID-19.

Are they helped or hindered by their government structure when it comes to a medical crisis?

SB: As I mentioned in my response to the first question, these nations will be very much hindered because of inability for governments to mobilize assistance in the same way as developed nations.

For lower-income countries, the fact that COVID-19 is a global pandemic will likely distinguish its response from other humanitarian responses, like that of the 2014-15 Ebola epidemic in West Africa and the 2010 earthquake in Haiti. Because those crises were more limited in scale, other nations not directly affected were able to contribute supplies, personnel, and support, which will probably be lacking for the COVID-19 response. Additionally, the capacity and resources of international organizations, such as the World Health Organization, are spread very thin in the current pandemic, meaning they will be less able to support individual country responses.

What are some of the other unique concerns/challenges do developing nations face?

SB: With regards to challenges, in addition to existing epidemics, Eastern DRC continues to face sporadic armed conflict and insecurity and, as a result, it is estimated that hundreds of thousands of people are internally displaced. This adds a monumental challenge to the COVID-19 response as these individuals and families will be particularly vulnerable, but also difficult to reach because of their displacement.

Who are the most vulnerable populations in these nations?

SB: To some extent, I think the most vulnerable populations will be similar in many settings, including those with underlying medical illnesses, the vulnerably housed, those facing poverty, persons with disabilities, individuals who are geographically isolated, and those with limited access to medical care. One of the key differences that will likely make the COVID-19 epidemic harder hitting in lower- and middle-income countries, however, is the higher burden of untreated or under-treated chronic illness, such as HIV/AIDS, TB, hepatitis, and malnutrition.

How is the COVID-19 crisis similar to the other humanitarian crises you have researched/worked on?

SB: In several respects, the COVID-19 response is similar to other humanitarian crises I have experience with. For example, both COVID-19 and humanitarian responses have a shared focus on the health of an entire population, as opposed to individuals (ex. implementation of public health measures, such as quarantine to protect the greater good). It also comes down to the essentials that are needed to meet people's basic needs and to keep people alive (ex. cancellation of all non-essential medical appointments and procedures). Furthermore, outcomes for the population at risk are largely dependent on the policies, programs, and supports implemented by various levels of government. And finally, something that many people can probably relate to—the feeling of uncertainty that comes with a crisis of this magnitude and when things are evolving so rapidly.

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Follow the latest news on the coronavirus (COVID-19) outbreak

Provided by Queen's University

How not to fall for coronavirus BS: Avoid the 7 deadly sins of thought

by Luke Zaphir, The Conversation

Credit: Shutterstock

With the COVID-19 pandemic causing a great deal of anxiety, we might come to think people are irrational, selfish or downright crazy. We see people showing up to public venues en masse or clearing supermarket shelves of toilet paper.

Experts are often ignored. We hear inconsistent information and arguments filled with fallacious reasoning being accepted by a seemingly large number people.

The answer for the kind of panicked flurry in reasoning may lie in a field of critical thinking called vice epistemology. This theory argues our thinking habits and intellectual character traits cause poor reasoning.

These thinking habits are developed over a lifetime.When these habits are poorly developed, we can end up with intellectual vices. The more we think viciously (as a vice), the harder it is for us to effectively inquire and seek truth.

Vice epistemology points to many thinking vices and sins that cause problems for inquiry. I have chosen seven that show up regularly in the literature:

1. Sin of gullibility

"I heard coronavirus particles can stay in the air for up to five days!"

Researchers found SARS-CoV-2, the virus that causes the disease COVID-19, remains infectious in airborne droplets for at least three hours.

But all sorts of claims are being touted by people and we're all guilty of having believed someone who isn't an expert or simply doesn't know what they're talking about. Gullibility as a thinking sin means that we lack the ability to determine the credibility of information.

Relevant expertise and experience are essential qualities when we're listening to someone's own argument. But with something like COVID-19, it's also important we look at the type of expertise someone has. A GP might be able to tell us how we get the infection—but they wouldn't count as an expert in infectious disease epidemiology (the way an infectious disease spreads across a population).

2. Sin of cynicism

"I'd better stock up on toilet paper before everyone else buys it."

In many ways, cynicism is the opposite of gullibility. It is being overly suspicious of others in their arguments and actions.

If you've suddenly become suspicious of your neighbours and what they might do when supermarket stocks are limited, that's a cynical way to think.

If we think the worst interpretation of arguments and events is correct, we can't inquire and problem-solve effectively.

3. Sin of pride

"I know what's best for my family!"

Pride is an intellectual sin (though it's more popular as a spiritual one). In this particular case, it is the habit of not admitting to ourselves or to others that we don't know the answer. Or perhaps that we don't understand the issue.

We obstruct a genuine search for truth if we are dogmatic in our self-belief.

It's effective reasoning to take what the evidence and experts say and then apply it specifically to our individual needs. But we have gone astray in our thinking if we contradict those who know more than us and are unwilling to admit our own limitations.

4. Sin of closed-mindedness

"I won't accept that."

Closed-mindedness means we're not willing to see things from different perspectives or accept new information. It's a serious intellectual vice as it directly interferes with our ability to adjust our beliefs according to new information.

Worse still, being close-minded to new ideas and information means it's even more challenging to learn and grow—we'd be closed minded to the idea that we're closed minded.

5. Sin of prejudice

"I've stopped buying Chinese food—just in case."

Prejudiced thinking is an intellectual vice we often start developing early in life. Children can be incredibly prejudiced in small ways—such as being unwilling to try new foods because they already somehow know they're gross.

As a character flaw, it means we often substitute preconceived notions for actual thinking.

6. Sin of negligence

"SARS was more deadly than COVID-19 and that wasn't that big a deal"

Creating a poor analogy like this one is not a substitute for thoughtful research and considered analysis.

Still, it is difficult to explore every single topic with thorough evaluation. There's so much information out there at the moment it can be a real chore to investigate every claim we hear.

But if we're not willing to check the facts, we're being negligent in our thinking.

7. Sin of wishful thinking

"This will all be over in a week or two and it'll be business as usual."

Our capacity to believe in ourselves, our hard work, our friends and culture can often blind us to hard truths.

It's perfectly fine to aim for a certain outcome but we need to recognise it doesn't matter how much we hope for it—our desire doesn't affect the likelihood of it happening.

A pandemic like COVID-19 shows our way of life is fragile and can change at any moment. Wishful thinking ignores the stark realities and can set us up for disappointment.

So what can we do about it?

There are some questions we can ask ourselves to help improve our intellectual character traits:

What would change my mind?

It's a red flag for sin of pride if nothing will change your mind.

What is the strongest argument the other side has?

We often hold each piece of the truth in our own perspective. It's worth keeping in mind that unless there's wanton cruelty involved, chances are differing arguments will have some good points.

What groups would gain or lose the most if we keep thinking this way?

Sometimes we fail to consider the practical outcomes of our thoughts for people who aren't like us. We've seen in the last few weeks that the people who have a lot to lose (such as casual workers) matter when it comes to the way we respond to the pandemic.

It's worth taking a moment to consider their perspectives.

How much do you actually know about an issue? Who is an expert?

The experts always have something to say. If they agree on it, it's a good indication we should believe them. If there isn't general consensus, we should be dubious of one-sided claims to truth.

And remember the person's actual expertise—it's too easy to mistake a political leader or famous person with an expert.

In challenging days like these, we may be able to help ensure a better outcome for everyone if we start by asking ourselves a few simple questions.Follow the latest news on the coronavirus (COVID-19) outbreak

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Provided by The Conversation 

Historical coronaviruses show evidence of seasonality and immunity

by University College London

Ultrastructural morphology exhibited by coronaviruses.  Credit: CDC Public Health Image Library,

Using historical data, a UCL research team has found that levels of infection from three common coronaviruses appear to have followed a seasonal pattern in England, with peaks occurring during winter and broadly at the same time as influenza.

The researchers found that only small amounts of coronavirus were transmitted in the summer.

The study, published today in Wellcome Open Research as a preprint ahead of peer review, uses data from the Flu Watch community cohort study from 2006 to 2011.

First author Dr. Rob Aldridge (UCL Institute of Health Informatics) said, "COVID-19 is a disease caused by the new coronavirus SARS-CoV2, but other related viruses have been around for some time. When we began data collection in 2006 there were at least three commonly circulating coronaviruses in the UK."

He and his colleagues used data their team had previously collected from the cohort study to understand whether there were greater numbers of infections caused by these coronaviruses in the winter or summer. They also looked at whether people got infected with these common coronaviruses more than once, knowing this information can show whether people developed immunity to the virus.

"Our findings support the idea that in the UK we could see continued but lower levels of coronavirus transmission in the summer, but this may reverse in the winter if there is still a large susceptible population at that point," Dr. Aldridge said.

"However, given this is a novel virus, we don't know if this seasonal pattern will hold over the summer due to high levels of susceptibility in the population. For this reason, it is crucial that we all act now to follow current health advice. Washing your hands and staying at home means you not only reduce your risk of getting COVID-19, but you are also protecting others by greatly reducing the chances of the virus spreading further in the community.

"Acting now gives scientists more time to develop vaccines and test new treatments for COVID-19, and it gives the NHS time to continue to get ready to help those that get sick.

"To understand more about whether COVID-19 will follow a pattern of higher numbers of infection in the winter, we need to learn from other countries in the southern hemisphere with temperate climates to see if this pattern of increasing levels of infection is observed during their winters over the coming months," he added.

Participants of the Medical Research Council and Wellcome-funded Flu Watch study in England were contacted weekly to report any symptoms of respiratory illnesses, and sent in swabs if they were ill. The current investigation included data from 199 positive cases of coronaviruses across three winters (November to March) and one summer (May to September) from 2006 to 2009. The researchers also looked at data from the following two winters to identify people who had a second coronavirus infection and see whether anyone was reinfected by the same virus.

The researchers were looking at infection patterns of three coronaviruses, HCoV-NL63, HCoV-OC43, and HCoV-229E, which they say bear similar symptoms to mild cases of SARS-CoV-2.

They found that the highest rates of coronavirus infections were in February, and very low in the summer season, when only four cases were detected. The findings are in line with previous research in other countries finding evidence that coronaviruses are seasonal in winter in temperate climates, with greater variation in tropical climates.

Last author Ellen Fragaszy (UCL Institute of Health Informatics and the London School of Hygiene & Tropical Medicine) said: "In temperate regions, many respiratory viruses follow a seasonal pattern with winter peaks during the 'cold and flu season." We believe this seasonality is driven in part by environmental factors such as temperature, humidity and sunlight which affect both virus survival and how well our immune systems can respond to these infections.

"Seasonality is also likely to be driven by our own behaviours such as our tendency when it's cold to spend more time indoors, with the windows shut and in close contact with other people."

The researchers say their results also provide some evidence of immunity against reinfection by the same virus, as they did not identify any people who were reinfected by the same virus. Based on their simulations, if people had no immunity after being infected, the probability of zero reinfections by the same virus in their study sample was only 3.48%, which they say suggests some immunity is likely.

The researchers say that more research is needed to see if their results will also apply to the SARS-CoV-2 virus, but given the lack of data on the novel virus, they hope that their findings can help inform the public health response.

"We cautiously infer from this that we might expect there to be some levels of immunity after infection with SARS-CoV2, but we don't know how strong or long this will last," said Dr. Aldridge.

"Our results support the idea that a vaccine could induce immunity to SARS-CoV2, but we need vaccine trials to examine this in detail and whilst this urgent and important work is being carried out, we all need to act to slow the spread of infection down and give scientists time to work on developing these new vaccines."

Follow the latest news on the coronavirus (COVID-19) outbreak

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More information: Seasonality and immunity to laboratory-confirmed seasonal coronaviruses (HCoV-NL63, HCoV-OC43, and HCoV-229E): results from the Flu Watch cohort study. wellcomeopenresearch.org/articles/5-52/v1

An all-organic proton battery energized for sustainable energy storage

by Uppsala University

Sustainable energy storage is in great demand. Researchers at Uppsala University have therefore developed an all-organic proton battery that can be charged in a matter of seconds. The battery can be charged and discharged over 500 times without any significant loss of capacity. Their work has been published in the scientific journal Angewandte Chemie.

The researchers have been able to demonstrate that their battery can be easily charged using a solar cell. Charging can also be accomplished without the aid of the advanced electronics that, for example, lithium batteries require. Another advantage of the battery is that it is unaffected by ambient temperature.

"I'm sure that many people are aware that the performance of standard batteries declines at low temperatures. We have demonstrated that this organic proton battery retains properties such as capacity down to as low as -24°C," says Christian Strietzel of Uppsala University's Department of Materials Science and Engineering.

A great many of the batteries manufactured today have a major environmental impact, not least due to the mining of the metals used in them.

"The point of departure for our research has therefore been to develop a battery built from elements commonly found in nature and that can be used to create organic battery materials," explains Christian Strietzel.

For this reason, the research team has chosen quinones as the active material in their battery. These organic carbon compounds are plentiful in nature, among other things occurring in photosynthesis. The characteristic of quinones that researchers have utilised is their ability to absorb or emit hydrogen ions, which of course only contain protons, during charging and discharging.

An acidic aqueous solution has been used as an electrolyte, the vital component that transports ions inside the battery. As well as being environmentally friendly, this also provides a safe battery free from the hazard of explosion or fire.

"There remains a great deal of further development to be done on the battery before it becomes a household item; however, the proton battery we have developed is a large stride towards being able to manufacture sustainable organic batteries in future," says Christian 

Schematic representation of the all‐organic battery concept, chemical structures/naming and polymerization method. The trimeric precursors (a) were used in the post‐deposition polymerization procedure (b) to form polymers with similar characteristics to those formed from monomeric units. In post‐deposition polymerization, the trimer is first dissolved in an organic electrolyte, followed by drop casting and drying. Subsequently, the trimer film is oxidized, either i) electrochemically in an aqueous 0.5 m H2SO4 solution by cyclic voltammetry between 0.0 and 1.21 V vs. SHE at 10 mV s−1 or by applying a potential of 0.81 V vs. SHE for 3000 s or ii) chemically by immersion into an acidic aqueous solution containing 1 m FeCl3 as oxidant, resulting in the formation of a black polymer layer. The anode material (c) consisted of pEP(NQ)E, which was formed by oxidative polymerization of EP(NQ)E. Similarly, the cathode material pEP(QH2)E (d) was formed from EP(QH2)E. Conductivity was achieved from a polythiophene backbone (e) that was oxidized/doped, for example, with HSO4−. The battery (middle) was assembled as an all‐organic proton battery using 0.5 m H2SO4 (aq) electrolyte, which enabled a rocking‐chair motion of the protons. The anode and cathode redox activity relies on the two‐electron two‐proton (2e2 H) redox process of the pendants (f and g). When the battery is charged, the quinone pendant groups are in the Q and NQH2 states, for the positive electrode (cathode) and negative electrode (anode), respectively. During discharge, the active cathode material is converted to QH2 while the anode is converted to NQ. E=3,4‐ethylenedioxythiophene; NQ=naphthoquinone; NQH2=naphthohydroquinone; P=3,4‐propylenedioxythiophene; p=polymerized; Q=benzoquinone; QH2=hydroquinone. Angewandte Chemie International Edition (2020). DOI: 10.1002/anie.202001191Strietzel.Fast-charging damages electric car batteries

More information: Christian Strietzel et al. An aqueous conducting redox polymer based proton battery that can withstand rapid constant‐voltage charging and sub‐zero temperatures, Angewandte Chemie International Edition (2020). DOI: 10.1002/anie.202001191

There's too much nitrogen and phosphorus in U.S. waterways

by Chrystian Tejedor, Florida International University

Credit: CC0 Public Domain

Even minor amounts of human activity can increase nutrient concentrations in fresh waters that can damage the environment, according to a new study.

These findings suggest most U.S. streams and rivers have higher levels of nitrogen and phosphorus than is recommended. Although nutrients are a natural part of aquatic ecosystems like streams and rivers, too much of either nutrient can have lasting impacts on the environment and public health.

In Florida, toxic blue-green algal blooms have been triggered by releases of phosphorus-laden waters from Lake Okeechobee. Algal blooms produce a foul odor along waterways, decrease dissolved oxygen, threaten insect and fish communities and can even produce toxins that are harmful to mammals and humans.

"Ecosystems are being loaded with legacy and current nitrogen and phosphorus, and their capacity to hold these nutrients in many cases is decreasing," said FIU associate professor John Kominoski, an ecologist and co-author of the study. "Not only are they being overwhelmed by nutrients, but they also have and continue to undergo hydrological and land use alterations."

As human populations and demands increasingly grow, more land—including wetlands—is converted to agricultural and urban uses. This can introduce more nitrogen and phosphorus onto the land, which eventually makes its way into bodies of water. To make matters worse, soil erosion and climate change are also impacting nutrient pollution, leading to nutrient export to coastal waters, Kominoski said.

Nitrogen is most likely to come from transportation, industry, agriculture and fertilizer application, while increased phosphorus is more commonly the result of sewage waste, amplified soil erosion and runoff from urban watersheds.

"High concentrations of nitrogen and phosphorus in our waterways are concerning because they threaten both human and ecosystem health," said David Manning, an assistant professor of biology at the University of Nebraska at Omaha and lead author on the paper. "Nutrients are essential for all life, but when they get too high in our waterways, they can fundamentally change the way a stream looks and operates."

In addition to causing algal blooms, these elevated nutrient concentrations can lead to a lack of species diversity and oxygen depletion. High nutrient concentrations can also affect the purity of the water we drink.

Nutrient pollution is a complex problem. While there's still a lot of work to be done to develop management tools and set thresholds for nutrient concentrations in streams and rivers, better understanding of how nutrients are transported through the interconnected network of waterways can help lead to solutions. Kominoski emphasized the importance of management solutions at local-to-global scales required to effectively manage various sources of nitrogen and phosphorus.

"Water is a shared resource that connects communities, landscapes, and continents across the globe," Kominoski said. "We must increase the protection and rehabilitation of ecosystems and water resources throughout the world, especially as human populations increase and climate changes."

The study was published in Ecological Applications

Researchers review environmental conditions leading to harmful algae blooms

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More information: David W.P. Manning et al. Transport of N and P in U.S. streams and rivers differs with land use and between dissolved and particulate forms, Ecological Applications (2020). DOI: 10.1002/eap.2130

Journal information: Ecological Applications

Provided by Florida International University 

Communicating the effectiveness of flood-mitigation plans

by University of Leeds

The graphic shows one of those hypothetical scenarios. With colour-coded overlays, it reveals how higher flood walls, more flood plains and river widening could provide the additional capacity to stop a repeat of the scale of flooding seen in 2015. Credit: University of Leeds

A team of Leeds mathematicians and French civil engineers has developed a new way of visualizing and analyzing complex flood-protection schemes.


They have steered away from equations and scientific language and have instead devised a graphical display that shows, as a hypothetical lake 2-meters deep, the amount of water that needs to be contained in a river valley to prevent flooding.

The graphic is overlaid with the various options necessary to hold back or to capture the flood waters, and how much each option will cost.

The work is a collaboration between applied mathematicians Professor Onno Bokhove, Professor Mark Kelmanson and Dr. Tom Kent from the School of Mathematics at the University of Leeds; and civil engineers Dr. Guillaume Piton and Dr. Jean-Marc Tacnet from Université Grenoble Alpes.

Professor Bokhove said: "This work started from a challenge thrown down by a representative of the Environment Agency in the UK who said mathematicians always produce equations and he wanted something that was more accessible, a way of communicating complex ideas clearly and simply, to allow the science underlying flood mitigation to be understandable to the wider fraternity involved in policy making."

The scientists revisited a concept at the heart of flood analysis. Known as flood-excess volume (FEV), it is the amount of water in a river system that cannot be contained by existing flood defenses, expressed as so many millions of cubic meters of water. However, for most people, including Professor Bokhove, that is an effectively meaningless measure that people cannot visualize.

They have described their approach in a paper, A cost-effectiveness protocol for flood-mitigation plans based on Leeds' Boxing Day 2015 floods , published in the journal Water.

To illustrate the idea, they used data from the floods on Boxing Day 2015, when the River Aire burst its banks in Leeds and caused extensive damage to homes and businesses estimated at around half a billion pounds.

Around 9.34 million cubic meters of water flooded from the River Aire.

That volume of flood water translates into a hypothetical square lake, 2 meters deep and with sides of 2.16 km in length. In comparison, the upper River Aire is about 50 miles long, with a valley width that varies roughly between 200 and 600 meters along its path.

Professor Bokhove added: "To have prevented the flood, you would have to somewhere deal with that volume of water. It is not inconceivable that, along the course of the river that additional water could be accommodated, either by increasing the size of flood plains, or by removing obstructions in the river, widening the river channel in places or by building higher flood walls: or, more likely, by combining some or all of those measures.

"Seeing flood mitigation this new way makes it easier for people to understand not only the interventions that are possible and the impact they are likely to have but also the costs associated with each such measure."

The researchers then used their novel graphical approach to analyze and communicate a hypothetical scheme for increasing the flood defenses in the center of Leeds to cope with not only a major flood that would be expected once in 100 years but also a one-in-200-year flood. They looked at several mitigation scenarios, their costs and their impact on river dynamics, an area of science known as fluid dynamics in which Leeds is a world leader.

Over the six years to 2021, the Government will have spent £2.6 billion on flood schemes in England, and further investment is expected.

Professor Bokhove said: "Our approach is intended to offer a means of comparing and choosing between flood-mitigation scenarios in a quantifiable and visual manner, thereby offering a better chance of them being understood by a wide audience including the general public, stakeholders and planners."


Explore furtherFlood alert: Researchers devise powerful new flood monitoring system for Japan
More information: Onno Bokhove et al. A Cost-Effectiveness Protocol for Flood-Mitigation Plans Based on Leeds' Boxing Day 2015 Floods, Water (2020). DOI: 10.3390/w12030652
Provided by University of Leeds

Insight into how insects sense and process pain and other negative stimuli

by Gina E. Mantica, Tufts University

“These findings are an important milestone for developing the tobacco hornworm as a new model system to help us understand the neural mechanisms of nociception and pain,” said Barry Trimmer, right, here with Daniel Caron in February. Credit: Anna Miller

Scientists know that most organisms react to things that cause them pain, but they know more about some species than others. Take the fruit fly—it's a favorite species to do all sort of research on, from genetics to, yes, how they detect pain.

But there is little known about how other insects sense harmful stimuli. Scientists at Tufts, including an undergraduate biology major, recently discovered that tobacco hornworm caterpillars, which range throughout the Americas, can sense and respond to different noxious stimuli using a single cellular mechanism. The researchers published a paper about the findings in the Journal of Experimental Biology in January.

Daniel Caron—a senior honors thesis student who worked in the lab of Barry Trimmer, the Henry Bromfield Pearson Professor of Natural Science—first set out to test whether the caterpillars respond differently when either struck with infrared lasers or prodded with narrow stainless steel rods.

Caron, with the help of Martha Rimniceanu, watched as the tobacco hornworm caterpillars quickly and precisely contorted their bodies around and touched where they felt pain, responding similarly to the heat from the lasers and the pressure from the rods.

Caron was curious why the caterpillars respond so similarly to two very different sensations. The team pursued a hunch that cells under the caterpillar's skin might be able to detect both types of heat and pressure, just like a group of cells in fruit flies that react to changes in pressure, temperature, and light.

Trimmer recalls Caron's passion for the project. "Like all good scientists, Dan built on others' work, in this case the pioneering senior thesis work of Martha, and carried out thoughtful and meticulous experiments to characterize these neurons," he said.

In order to study how the caterpillars' cells respond to heat and pressure, Caron had to learn a technique to examine the activity of caterpillars' miniscule cells. He spent an entire semester learning how to attach tiny glass electrodes to cells, to be able to record their electrical activity. After months of frustration, he successfully recorded the activity of cells under the caterpillar's skin while simultaneously poking the skin around the cells with either lasers or metal rods.

As predicted, the same cells could respond to both heat and mechanical pressure—just like a group of cells in fruit flies.

To make sure that he really had looked at responses from just a single cell rather than a group of similar cells, Caron prodded the area again with his lasers and rods, but now at a much faster rate. That tested whether a singular cell would respond to both types of noxious stimuli, rather than two similar cells responding separately to each stimulus. If it was a single cell, the activity of that cell should decrease over time as it got used to the repeated stimulation.

At first, Caron could not see any change in how the cells responded, so he tried striking the cells at a very rapid rate.

His perseverance once again led to a novel discovery. In these cases, the cells under the skin didn't just decrease their responsiveness to both types of stimuli; sometimes the cells didn't respond at all.

To ensure that this change wasn't from simply having damaged the cells, Caron made sure that the cells eventually reacted again to both heat and pressure. Not only did this confirm that he recorded from single cells, but it also is the first piece of evidence of a cellular "depression" in insects in response to harmful repeated poking.

Since the fruit fly and the tobacco hornworm are separated by more than 260 million years of evolution, this finding suggests that the cellular mechanism underlying how pain is sensed might be highly conserved across species. This means that other species might also have similar mechanisms for sensing pain.

Trimmer concurs. "These findings are an important milestone for developing the tobacco hornworm as a new model system to help us understand the neural mechanisms of nociception and pain," he said. Caron's discovery of the similarities between tobacco hornworms and fruit flies could inform future research on pain and nociception in other animals, including humans.

"This shows how Tufts undergraduates are making significant contributions to science," said Trimmer. "I am proud of Dan and Martha's hard work and intellectual accomplishments."

First treatment for pain using human stem cells a success

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More information: Daniel P. Caron et al. Nociceptive neurons respond to multimodal stimuli in Manduca sexta, The Journal of Experimental Biology (2020). DOI: 10.1242/jeb.218859

Journal information: Journal of Experimental Biology 

Study shows large ocean predators are more active in temperate regions

by Bob Yirka , Phys.org

a Global map depicting median annual relative predation between 1960 and 2014 at 5° × 5° resolution. The tropics are defined as the region between latitudes 23.5°S and 23.5°N. b Partial effect of latitude on variation in relative predation in a generalized additive mixed-effect model (GAMM) run separately for each of four ocean basins (P-values for the partial effect of latitude are below 0.0001 in all four GAMMs; see Supplementary Table 4 for details). This analysis accounted for the effects of both time and spatial autocorrelation in the data. Blue lines depict the GAMM-predicted function with 95% confidence intervals (gray shading). Gray circles indicate median relative predation per latitude within 5-year time intervals. Credit: Nature Communications (2020). DOI: 10.1038/s41467-020-15335-4

An international team of researchers has found that large ocean predators such as tuna, marlin and sharks are more active in temperate regions. In their paper published in the journal Nature Communications, the group describes their analyses of data on attacks by predators on fishing bait in the open ocean over more than a half-century, and what it showed them.


Over the past several decades, Earth scientists have developed a theory called the "biotic interactions hypothesis," which suggests that species interactions (such as predation) are the driving force in creating biodiversity in different parts of the ocean—large predators such as sharks and tuna prey on smaller marine creatures, resulting in biodiversity. The theory has been used to explain why the greatest biodiversity in the world's oceans is near the equator—because there is more predation by large predators. But in recent years, support for the theory has begun to wane as scientists report evidence of exceptions. In this new effort, the researchers have found evidence that will likely overturn the theory completely.

The work involved analyzing data describing attacks on fishing bait by large ocean predators in the open ocean for the years 1960 to 2014. In all, the researchers studied 900 million recorded incidents of large predators trying to steal bait off fishermen longlines.

The researchers found the opposite of what they expected in the data—attacks were more prevalent in temperate regions than they were nearer to the equator. More specifically, they found that most attacks occurred in the mid-latitudes in the 30- to 60-degree range. They also found that the number of attacks was not associated with the degree of biodiversity in a given region.

The researchers wondered if their findings might be tied to industrial fishing, so they compared predator hits over time with fish tallies. They found that predation did drop as more prey were taken from the ocean, but it did not change the ratios of hits between regions—large predators still preferred the mid-latitudes. They suggest their findings will lead to new efforts to explain why there is greater diversity at the equator than in other regions of the oceanIndustrial fishing behind plummeting shark numbers

More information: Marius Roesti et al. Pelagic fish predation is stronger at temperate latitudes than near the equator, Nature Communications (2020). DOI: 10.1038/s41467-020-15335-4

Journal information: Nature Communications

Ocean deoxygenation: A silent driver of coral reef demise?

by University of Technology, Sydney

Coral reefs are constantly under threat from environmental stress. Credit: David Suggett

The existence of coral reefs, in all their abundant biodiversity and beauty, relies largely on a complex symbiosis between reef-building corals and microalgae. This finely tuned, fragile, partnership is constantly under threat from environmental stress—most notably the twin effects of warming waters and ocean acidification caused by climate change. But scientists say a third driver, that of ocean deoxygenation, could pose a greater and more immediate threat to coral reef survival. 

A perspective paper published in Nature Climate Change brings together existing biological, ecological, and geochemical evidence to consider the broader role for ocean deoxygenation in global coral reef degradation. The University of Technology Sydney (UTS) led study has found that the threat of ocean deoxygenation to coral reefs has largely been ignored and remains unaccounted-for in predictions about future reef health. This is despite reef-building corals underpinning both the ecological and economic value of the world's coral reef ecosystems.

Lead author, Dr. David Hughes, a Research Associate at the UTS Climate Change Cluster, said that measurements taken over the last 50 years showed oxygen levels in the world's oceans have already declined by around 2% "largely due to the dual forces of global climate change and coastal pollution caused by nutrient runoff."

"Our oceans are slowly suffocating and although we have some understanding about deoxygenation in the open ocean this process has been largely overlooked in coastal tropical reef systems.

"Although oxygen is a relatively easy environmental variable to measure, there is surprisingly very little data available for coral reefs," he said.

The authors, who also include scientists from the University of Copenhagen, Denmark and University of Konstanz, Germany, say this lack of data makes it very difficult to assess what normal oxygen levels are on coral reefs or the dissolved oxygen threshold at which areas might become "dead zones."

"We simply don't know what constitutes lethal or sub-lethal oxygen thresholds within coral reefs or the role such thresholds will play in determining what future reefs will look like," Dr. Hughes said.

Associate Professor David Suggett, senior author and leader of the Future Reefs Research Program at UTS said it's likely that understanding the impact of deoxygenation for places like the Great Barrier Reef "holds the key to being able to more accurately predict the future for coral reefs."

"Oxygen fundamentally sustains reef life.

"It's possible that declining oxygen availability has amplified, and will continue to amplify, the impact of catastrophic events such as heat-wave driven mass coral bleaching. Capacity for organisms to resist stressors is severely compromised under reduced oxygen availability. It's why we give oxygen to humans under trauma," he said.

"Identifying thresholds of low oxygen tolerance and how they vary across coral reef-associated species and environmental history is arguably the key step in understanding

how reef communities will respond to continued ocean deoxygenation," Associate Professor Suggett said.

The authors say that unlike the deep knowledge gained over the past 30 years around the twin impacts of temperature and pH levels, there wasn't the same depth of knowledge about ocean deoxygenation and, therefore, how this will shape reef ecologies.

Suggett and Hughes say establishment of an oxygen sensor network on the GBR would be a good place to start and could help develop an oxygen inventory of the reef to enable new approaches and management practices.

A positive outcome from the study is the sign that local management is crucial to preventing further deoxygenation in coastal waters.

"The resources being mobilized to improve agricultural and catchment management on the GBR are good examples of practices to ensure the oxygen stocks of coastal reefs," Associate Professor Suggett said.

"Everyone has a role to play to ensure our reefs don't suffocate further," he said.

Coral reefs: Centuries of human impact

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More information: David J. Hughes et al. Coral reef survival under accelerating ocean deoxygenation, Nature Climate Change (2020). DOI: 10.1038/s41558-020-0737-9