It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
First author Dr. Kayla Dadgar. Credit: Kayla Dadgar
Scurvy, the debilitating condition remembered as a disease of pirates, is still found in Canada.
The disease, which is caused by a vitamin C deficiency, can result in bruising, weakness, anemia, gum disease, hemorrhage, tooth loss, and even death if undiagnosed and untreated.
McMaster University researchers surveyed the data of patients of Hamilton's two hospital systems over nine years and found 52 with low Vitamin C levels. This included 13 patients who could be diagnosed as having scurvy, and an additional 39 who tested positive for scurvy but did not have documented symptoms.
Among those with scurvy, some were related to alcohol use disorder or to bariatric surgery but the majority were related to other causes of malnutrition such as persistent vomiting, purposeful dietary restrictions, mental illness, social isolation and dependence on others for food.
"Scurvy is seen as a disease irrelevant to the modern world, but it still exists, and clinicians caring for at-risk patients should be aware of it and know how to diagnose it," said John Neary, associate professor of medicine at McMaster and the senior author of the study published this month in the Journal of General Internal Medicine.
First author Kayla Dadgar, who did the research as a medical student at McMaster, said: "Scurvy should be a 'never event' in a healthy society. That it still occurs in Canada in our time indicates that we are not supporting vulnerable people as we should."
The patients with scurvy who were given Vitamin C had a rapid recovery of their symptoms.
More information: Kayla Dadgar et al, Clinical Profile of Scurvy in Hamilton Since 2009: a Cohort Study, Journal of General Internal Medicine (2020). DOI: 10.1007/s11606-020-05636-1
Using waste carbon dioxide to separate metals from ores
by Bob Yirka , Phys.org JANUARY 17, 2020
a, First level: carbamation, dC. Reversible carbamate N–CO2 bond formation (eq. 1) and hydrolysis (eq. 2) deliver the subsystem of organic species. b, Second level: ligation, dL. Binding of nucleophilic species such as amines (eq. 3), carbamates and amines (eq. 4), carbamates and halides (eq. 5) or carbamates exclusively (eq. 6) in the first coordination sphere of the metal deliver the subsystem of complexes. c, Third level: ion pairing, dIP. Salt bridge formation between species of opposite charge including halides, ammonium carbamates and ligated metal are exemplified by metal–ammine adducts paired with carbamate counter-ions (eq. 7) and carbamato–metal adducts paired with metal–ammine complexes (eq. 8). Credit: Nature Chemistry (2020). DOI: 10.1038/s41557-019-0388-5
A combined team of researchers from the University of Lyon and the University of Turin has developed a way to use waste CO2 to separate metals used in products. In their paper published in the journal Nature Chemistry, the group describes their process and why they believe it can be used as a global warming mitigation tool.
Scientists have promoted the idea of using carbon capture and storage (CCS) as a way to reduce the amount of CO2 emitted into the atmosphere. CCS involves capturing the exhaust from a car or a factory, removing the CO2 and then storing it until scientists develop a use for it.
Unfortunately, CCS has proven to be too expensive for commercial use. In this new effort, the researchers developed a way to use waste CO2 to create ligands for separating metals from ores. The recovered metals can then be sold for use in making products such as smartphone components. Their idea is to recoup the cost of capturing CO2 (or make it profitable) so that businesses will find it more economically viable. The researchers claim their approach is the first to use two waste streams as part of a process that yields multiple purified compounds in a single pot.
In their process, the CO2 serves as a type of bonding agent—it takes advantage of the attraction of ligands for metals using temperature and pressure. The team injected 2,2'-Iminodi(ethylamine) solution into a mix of LaCl3 and NiCl2 to demonstrate how their approach works. They then bubbled CO2 from car exhaust through the mix. Doing so resulted in 2,2'-Iminodi(ethylamine) capturing carbon dioxide and producing ligands that bound with lanthanum.
After a few minutes, crystals containing lanthanum formed, and the nickel that was bound to unreacted diethylenetriamine remained in the solution. Both metals were then recovered using a centrifuge—testing showed both were 99 percent pure. A second test involved separating useful metals from an electrode taken from a nearly dead battery—it yielded cobalt, nickel and lanthanum. The researchers claim a secondary benefit of their approach is that it is a greener way to separate metals from ores than standard methods.
More information: Jean Septavaux et al. Simultaneous CO2 capture and metal purification from waste streams using triple-level dynamic combinatorial chemistry, Nature Chemistry (2020). DOI: 10.1038/s41557-019-0388-5
Using machine learning to fine-tune views of the ancient past
by Bob Yirka , Phys.org JANUARY 17, 2020
Credit: Nanjing University
A team of researchers affiliated with several institutions in China and two in the U.S. has developed a way to use machine learning to get a better look at the past. In their paper published in the journal Science, the group describes how they used machine learning to analyze records of the past.
Scientists use fossils to date rocks because they have no way to test the age of rock directly. Prior research has shown that most species only exist for a certain amount of time. If scientists determine the time when a given dinosaur lived in a given area, they can use that information to date the local rocks using the fossils embedded within them. A drawback to this method of dating rocks is that it does not give scientists a very fine filter when attempting to create a timeline of historical events such as mass extinctions.
A decade ago, a group of mathematicians developed a statistical approach to creating a biodiversity timeline based on analyzing hundreds of thousands of records of marine and land fossils. Their method would have allowed scientists to divide the past several hundred million years into small spans of time. This would have provided a finer view of what has transpired. Unfortunately, it took dozens of months to run the programs—too long for practical use. In this new effort, the researchers have resurrected the work by the mathematicians by applying machine learning to the data and then analyzing the results on a Tianhe-2 supercomputer.
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Paleontologists use big data and supercomputers to recover marine paleobiodiversity. Credit: Nanjing University, We Video
The researchers entered data covering approximately 300 million years—from the beginning of the Cambrian period, approximately 540 million years ago, until shortly after the Triassic period began, approximately 240 million years ago. The computer returned results for periods of time as short as 26,000 years. They compared the difference in resolution to looking at six months of people living during a given time period versus a century.
The researchers found the timeline produced by the computer differed in some ways from the timeline produced using longer periods of time. For example, one of the five great mass extinctions believed to have happened did not actually happen—it was more of a slow change in biodiversity.
More information: Jun-xuan Fan et al. A high-resolution summary of Cambrian to Early Triassic marine invertebrate biodiversity, Science (2020). DOI: 10.1126/science.aax4953
Climate may play a bigger role than deforestation in rainforest biodiversity
JANUARY 17, 2020By measuring characteristics like ear, foot, and tail size in species like Euryoryzomys russatus, researchers can quantify functional diversity in large rainforests. Credit: Ricardo S. Bovendorp
"Save the rainforests" is a snappy slogan, but it doesn't tell the full story of how complicated it is to do just that. Before conservationists can even begin restoring habitats and advocating for laws that protect land from poachers and loggers, scientists need to figure out what's living, what's dying, and which patterns explain why. Tackling these questions—in other words, finding out what drives a region's biodiversity—is no small task.
The better we measure what's in these rainforests, the more likely we are to find patterns that inform conservation efforts. A new study in Biotropica, for instance, crunched numbers on a behemoth dataset on small mammals in South America and found something surprising in the process: that climate may affect biodiversity in rainforests even more than deforestation does.
"When we think about biodiversity, we usually think about the number of species in a particular place—what we call taxonomic diversity," says de la Sancha. "This paper aims to incorporate better measures of biodiversity that include functional and phylogenetic diversity."
Functional diversity looks at biodiversity based on the roles organisms play in their respective ecosystems. Rather than simply counting the species in an area, scientists can use categories—"Do these mammals primarily eat insects, or do they primarily eat seeds?" and "Do they only live on the forest floor, or do they live in trees?" as well as quantitative characters like weight and ear, foot, and tail size, for instance—to determine and quantify how many different ecological roles a habitat can sustain.
Meanwhile, phylogenetic diversity looks at how many branches of the animal family tree are represented in a given area. By this measure, a patch of land consisting almost entirely of closely-related rodents would be considered far less diverse than another that was home to a wide genetic range of rodents, marsupials, and more—even if the two patches of land had the same number of species.
By applying these approaches to data on all known small mammal species and all those species' characteristics, scientists are able to see the forest from the trees, uncovering patterns they wouldn't have using any single dimension of diversity alone.
This is how de la Sancha and his co-authors found, based on functional and phylogenetic measures, that while deforestation causes local extinctions, climate-related variables had more of an effect on small mammal biodiversity patterns across the entire forest system.
In other words, if a section of rainforest was cut down, some of the animals living there might disappear from that area, while the same species living in intact patches of rainforest could survive. And, the researchers found, even if a species disappears from one area, different species that play a similar role in the ecosystem tend to replace them in other forest patches and other parts of the forest system. Meanwhile, changes to the climate may have big, sweeping effects on a whole rainforest system. This study found that BIO9, a bioclimatic variable measuring mean temperature of the driest quarter—more simply put, how hot the forest is in its least rainy season—affects biodiversity across the whole forest system.
Knowing these climate variables play a role in rainforest health can be concerning. This study and others provide strong evidence of climate change's effects on large ecosystems, underlining the urgency of studying and protecting habitats like the Atlantic Forest, the South American forest system at the center of the study.
"We still have so much that we don't know about so many of these species, which underlines the necessity for more fieldwork," de la Sancha says. "Once we have more specimens, we can improve how we quantify functional diversity and our understanding of why these small mammals evolved the way they did. From there, we can keep better track of biodiversity in these areas, leading to improved models and conservation strategies down the line."
Still, with only 9-16 percent of the Atlantic Forest's original habitat space remaining, this study lends a silver lining to an otherwise grim narrative about the effects of human activity on rainforests.
"I think this gives us a little bit of hope. As long as we have forest—and we need to have forest still—we can maintain biodiversity on a large scale," de la Sancha says. "As long as we don't wipe it all out, there's good evidence to show that we can maintain biodiversity, at least for small mammals, and the ecosystem services these critters provide."
More information: Noe U. de la Sancha et al. Disentangling drivers of small mammal diversity in a highly fragmented forest system, Biotropica (2020). DOI: 10.1111/btp.12745
Human-caused biodiversity decline started millions of years ago
Dinofelis, painting by Mauricio Antón. The picture shows a saber-toothed cat Dinofelis eating while one of our ancestors are watching. Dinofelis has been considered a predator that our ancestors were greatly fearing. But new research suggests that it was human ancestors that may have caused the eventual extinction of the species along with other major predators. Credit: University of Gothenburg
The human-caused biodiversity decline started much earlier than researchers used to believe. According to a new study published in the scientific journal Ecology Letters the process was not started by our own species but by some of our ancestors.
The work was done by an international team of scientists from Sweden, Switzerland and the United Kingdom.
The researchers point out in the study that the ongoing biological diversity crisis is not a new phenomenon, but represents an acceleration of a process that human ancestors began millions of years ago.
"The extinctions that we see in the fossils are often explained as the results of climatic changes but the changes in Africa within the last few million years were relative minor and our analyses show that climatic changes were not the main cause of the observed extinctions," explains Søren Faurby, researcher at Gothenburg University and the main author of the study.
"Our analyses show that the best explanation for the extinction of carnivores in East Africa is instead that they are caused by direct competition for food with our extinct ancestors," adds Daniele Silvestro, computational biologist and co-author of the study.
Carnivores disappeared
Our ancestors have been common throughout eastern Africa for several million years and during this time there were multiple extinctions according to Lars Werdelin, co-author and expert on African fossils.
Elephant. Credit: Hans Ring, Naturfotograferna
– By investigating the African fossils, we can see a drastic reduction in the number of large carnivores, a decrease that started about 4 million years ago. About the same time, our ancestors may have started using a new technology to get food called kleptoparasitism, he explains.
Kleptoparasitism means stealing recently killed animals from other predators. For example, when a lion steals a dead antelope from a cheetah.
The researchers are now proposing, based on fossil evidence, that human ancestors stole recently killed animals from other predators. This would lead to starvation of the individual animals and over time to extinction of their entire species.
"This may be the reason why most large carnivores in Africa have developed strategies to defend their prey. For example, by picking up the prey in a tree that we see leopards doing. Other carnivores have instead evolved social behavior as we see in lions, who among other things work together to defend their prey," explains Søren Faurby.
Humans today affect the world and the species that live in it more than ever before.
"But this does not mean that we previously lived in harmony with nature. Monopolization of resources is a skill we and our ancestors have had for millions of years, but only now are we able to understand and change our behavior and strive for a sustainable future. "If you are very strong, you must also be very kind,'" concludes Søren Faurby, quoting Astrid Lindgrens' book about Pippi Longstocking.
More information: Søren Faurby et al. Brain expansion in early hominins predicts carnivore extinctions in East Africa, Ecology Letters (2020). DOI: 10.1111/ele.13451
CMU and NOAA mobile laboratories, collecting data in downtown Pittsburgh. Credit: CMU College of Engineering
Despite the prominent health threat posed by fine particulate pollution, fundamental aspects of its formation and evolution continue to elude scientists.
This is true especially for the organic fraction of fine particles (also called aerosol), much of which forms as organic gases are oxidized by the atmosphere. Computer models under-predict this so-called "secondary" organic aerosol (SOA) in comparison to field measurements, indicating that the models are either missing some important sources or failing to describe the physical processes that lead to SOA formation.
New research from Carnegie Mellon University in collaboration with the National Oceanic and Atmospheric Administration (NOAA) sheds light on an under-appreciated source of SOA that may help close this model-measurement gap. Published in Environmental Science & Technology, the study shows that volatile organic compounds (VOCs) not traditionally considered may contribute as much or more to urban SOA as long-accounted for sources like vehicle emissions and respired gases from tree leaves.
"Our experiment shows that, in areas where you have a lot of people, you can only explain about half of the SOA seen in the field with the traditional emissions from vehicles and trees," said Albert Presto, a professor in mechanical engineering and the study's corresponding author. "We attribute that other half to these non-traditional VOCs."
In 2018, researchers from NOAA made a splash in the journal Science when they detailed how non-traditional VOCs represent half of all VOCs in the urban atmosphere in U.S. cities. Non-traditional VOCs originate from a slew of different chemicals, industries, and household products, including pesticides, coatings and paints, cleaning agents, and even personal care products like deodorants. Such products typically contain organic solvents whose evaporation leads to substantial atmospheric emissions of VOCs.
Rishabh Shah's ‘oxidative flow reactor,’ which speeds up atmospheric processing to quickly capture air’s full potential to form secondary particles. Credit: CMU College of Engineering
"It's a lot of everyday stuff that we use," said Presto. "Anything you use that is scented contains organic molecules, which can get out into the atmosphere and react" where it can form SOA.
The prevalence of these VOCs represents a paradigm shift in the urban SOA picture. The transportation sector had long been the dominant source of VOCs in urban air, but vehicle emissions in the U.S. have decreased drastically (up to 90%) due to tailpipe regulations in recent decades, even as fuel consumption has risen. As transportation-related VOCs have faded in prominence, non-traditional VOCs have begun to make up a greater relative contribution to the urban atmosphere. While NOAA's research alerted to atmospheric science community to the magnitude of non-traditional VOCs in urban environments, they could only hypothesize that these gases were likely important for SOA formation; the idea still needed to be tested.
Testing how much SOA forms from these is not an easy task, however. SOA formation in the atmosphere plays out over the course of several days, making it difficult to track the journey of emitted gases as they are dispersed by winds and begin reacting with sunlight and other oxidants.
Rishabh Shah, a graduate student who studied with Presto and now works at NOAA, constructed a reactor to evaluate the full potential for SOA formation within a sample of air without having to track that air over time.
"The reactor is kind of like an app on your smartphone for SOA formation," said Shah. "You take your picture and the app shows you what you would look like a decade from now."
The reactor accelerates the meandering journey a gas takes by bombarding it with oxidants at much higher concentrations than are found in the atmosphere. This physically simulates in just a few seconds all of the reactions a gas molecule is subject to in the atmosphere over the course of a week. In just a moment's time, Shah's reactor can evaluate the full potential of the air it samples to form SOA.
The team mounted their reactor in a van, creating a mobile platform from which they could access air from different settings containing varying levels of non-traditional VOCs. These locations included sites downwind from a large industrial facility, next to a construction site, within the deep 'street canyons' created by the skyscrapers of a city center, and among low-rise buildings of an urban neighborhood.
In places with large amounts of non-traditional VOCs, the reactor formed large amounts of SOA. These locations included both downtown street-canyons and amongst the urban low-rises, both places where evaporation of consumer products like deodorants and conditioners are high, especially in the morning. Advanced gas-analyzers aboard the mobile platform allowed the team to detect the presence of many of these non-traditional VOCs.
Importantly, in these locations the standard state-of-the-art computer models could not predict the full amount of SOA they observed in their reactor. However, in other environments with fewer non-traditional VOCs, the model was able to accurately predict how much SOA formed in the reactor.
Together, these pieces of evidence form a compelling argument that non-traditional VOC emissions are responsible for a significant amount of urban SOA. Presto estimates that these non-traditional emissions have roughly the same contribution as transportation and biosphere emissions combined, in line with the hypothesis put forward by NOAA.
"Traditionally, we've focused a lot on power plants and vehicles for air quality, which have gotten way cleaner in the U.S.." said Presto. "What that means is that now, a substantial amount of the SOA is coming from this other 'everyday, everywhere' category that hasn't really been considered until recently."
Gray wolves, like this pair on Isle Royale, are listed as endangered in the United States. Credit: Michigan Technological University
What makes for an endangered species classification isn't always obvious.
Lions and leopards are endangered species. Robins and raccoons clearly are not. The distinction seems simple until one ponders a question such as: How many lions would there have to be and how many of their former haunts would they have to inhabit before we'd agree they are no longer endangered?
To put a fine point on it, what is an endangered species? The quick answer: An endangered species is at risk of extinction. Fine, except questions about risk always come in shades and degrees, more risk and less risk.
Extinction risk increases as a species is driven to extinction from portions of its natural range. Most mammal species have been driven to extinction from half or more of their historic range because of human activities.
The query "What is an endangered species?" is quickly transformed into a far tougher question: How much loss should a species endure before we agree that the species deserves special protections and concerted effort for its betterment? My colleagues and I put a very similar question to nearly 1,000 (representatively sampled) Americans after giving them the information in the previous paragraph. The results, "What is an endangered species?: judgments about acceptable risk," are published today in Environmental Research Letters.
Three-quarters of those surveyed said a species deserves special protections if it had been driven to extinction from any more than 30% of its historic range. Not everyone was in perfect agreement. Some were more accepting of losses. The survey results indicate that people more accepting of loss were less knowledgeable about the environment and self-identify as advocates for the rights of gun and land owners. Still, three-quarters of people from the group of people who were more accepting of loss thought special protections were warranted if a species had been lost from more than 41% of their former range.
These attitudes of the American public are aligned with the language of the U.S. Endangered Species Act—the law for preventing species endangerment in the U.S. That law defines an endangered species as one that is "in danger of extinction throughout all or a significant portion of its range."
But There Might Be A Problem
Government decision-makers have tended to agree with the scientists they consult in judging what counts as acceptable risk and loss. These scientists express the trigger point for endangerment in very different terms. They tend to say a species is endangered if its risk of total and complete extinction exceeds 5% over 100 years.
Before human activities began elevating extinction risk, a typical vertebrate species would have experienced an extinction risk of 1% over a 10,000-year period. The extinction risk that decision-makers and their consultant experts have tended to consider acceptable (5% over 100 years) corresponds to an extinction risk many times greater that the extinction risk we currently impose on biodiversity! Experts and decision-makers—using a law designed to mitigate the biodiversity crisis—tend to allow for stunningly high levels of risk. But the law and the general public seem accepting of only lower risk that would greatly mitigate the biodiversity crisis. What's going on?
One possibility is that experts and decision-makers are more accepting of the risks and losses because they believe greater protection would be impossibly expensive. If so, the American public may be getting it right, not the experts and decision-makers. Why? Because the law allows for two separate judgements. The first judgement is, is the species endangered and therefore deserving of protection? The second judgment is, can the American people afford that protection? Keeping those judgements separate is vital because making a case that more funding and effort is required to solve the biodiversity crisis is not helped by experts and decision-makers when they grossly understate the problem—as they do when they judge endangerment to entail such extraordinarily high levels of risk and loss.
Facts and Values
Another possible explanation for the judgments of experts and decision-makers was uncovered in an earlier paper led by Jeremy Bruskotter of Ohio State University (also a collaborator on this paper). They showed that experts tended to offer judgments about grizzly bear endangerment—based not so much their own independent expert judgement—but on basis of what they think (rightly or wrongly) their peers' judgement would be.
Regardless of the explanation, a good answer to the question, "What an endangered species?" is an inescapable synthesis of facts and values. Experts on endangered species have a better handle on the facts than the general public. However, there is cause for concern when decision-makers do not reflect the broadly held values of their constituents. An important possible explanation for this discrepancy in values is the influence of special interests on decision-makers and experts charged with caring for biodiversity.
Getting the answer right is of grave importance. If we do not know well enough what an endangered species is, then we cannot know well enough what it means to conserve nature, because conserving nature is largely—either directly or indirectly—about giving special care to endangered species until they no longer deserve that label.
More information: Tom Offer-Westort et al, What is an endangered species?: judgments about acceptable risk, Environmental Research Letters (2020). DOI: 10.1088/1748-9326/ab5cc8
Saturday, January 18, 2020
France's art of the protest: the Louvre falls victim to pension reform strike
Industrial action over planned pension reforms is in its 44th day here in France. Workers forced the closure of the world's most visited museum, the Louvre. Some voiced their frustration - and one critic has become the focus of attention on social media. Plus, Eminem ignites controversy with a new song referencing the Manchester bombing that killed 22 people.
Dancing, singing and disrobing: France's unusual pension reform protests
Issued on: 17/01/2020
Striking ballerinas perform a free public show in Paris on
From dancing ballerinas to disrobing lawyers, French workers protesting the current pension reforms and other grievances have been finding innovative and eye-catching ways to show their discontent.
France has been hit by strikes and protests for the past six weeks, driven by anger over government plans to streamline the country’s complex pension system. But numbers at demonstrations have been dwindling in recent days amid signs the movement is running out of steam.
Some, however, have turned to alternative forms of protest to express their discontent at the reforms and other grievances in often eye-catching and innovative ways.
The trend began on December 24 last year when striking ballet dancers performed a free show on the steps of the famed Palais Garnier opera house in Paris. A week later, members of the Paris Opera orchestra followed suit with their own public performance.
Others have been using the tools of their trades to get their point across, including lawyers symbolically ditching their robes at the feet of the country’s justice minister, doctors discarding their white coats and teachers jettisoning their textbooks.
Further innovative forms of protest have seen firefighters turn their hoses on government buildings, flashmob dance routines spring up and striking forensics police staging grisly crime scenes.
Dozens of protesters tried to enter a Paris theatre on Friday where French President Emmanuel Macron was spending the evening with his wife Brigitte.
Around thirty opponents of Macron’s pension reform gathered in front of Paris’s Bouffes du Nord theatre early Friday evening, according to the presidential couple's entourage. After trying to enter the theatre, the demonstrators were moved back by police.
The head of state, who was attending a performance at the time, was "secured" for a few minutes before being able to return to see the play until the end.
The Paris Police headquarters confirmed that the demonstrators had not managed to enter.
The Macrons were attending a performance of "La Mouche" when the activist journalist Taha Bouhafs, sitting three rows behind, tweeted photos that prompted activists to come and disrupt the show, according to a relative of the president.
"We were at Paris 7 University for a people's university, someone got a message that Macron was there, so we came to show that we're here, that there's a protest against pension reform, but not only that," said Arthur Knight, one of the protesters.
Bouhafs then asked his tens of thousands of followers whether he should throw his shoes at the president, following the famous gesture of an Iraqi journalist against US President George W. Bush in 2008.
"I'm kidding (...) the security is looking at me weirdly right now," Bouhafs said.
Bouhafs was later arrested and taken into police custody overnight on the grounds he had acted to incite both damage to property and violence.
The president "will continue to go to theatrical performances as usual”, said his entourage. “He will be careful to defend creative freedom so that it is not disrupted by violent political actions.”
The French president has not been seen in public since his appearance in Amiens on 21 and 22 November, before protests against his controversial pension reform kicked off on December 5.
Friday marked the 44th day of a record-breaking transport strike where protesters also targeted the headquarters of the CFDT union, which supports the universal points-based retirement system, and blocked the entrance to the Louvre.
