New method can quickly and accurately detect infections

New electrochemical method developed at UTSA to test the presence of a bacterial infection is faster and more accurate than methods currently on the market.

A new study by Waldemar Gorski, professor and chair of the UTSA Department of Chemistry, and Stanton McHardy, associate professor of research in chemistry and director of the UTSA Center for Innovative Drug Discovery, describes a method that could show quickly and accurately whether a person has been infected with harmful bacteria or other pathogens. Additionally, this new method shows the exact severity of infection in a person.

The most common method of testing for infection in medical facilities is currently a strip that turns a certain color when infected fluids come into contact with it.

"The problem with this method is that it's imprecise," Gorski said. "The human eye is forced to judge the level of infection based on the hue and deepness of a color. It's difficult to make an accurate call based on that." Furthermore, roughly a third of samples cannot be tested because the fluids contain blood or are too opaque.

Other methods include microbiology or examining body fluid samples under a microscope and counting white blood cells, also known as leukocytes, which are an indicator of an infection. However, these can be slow processes and require more highly trained personnel.

Gorski, seeing a need for an easier and more rapid method of testing for infection, resolved to test an electrochemical approach, and sought out McHardy, a medicinal chemist. Together, they created molecules that bind to leukocyte enzymes and produce an electrical current to signal the presence of an infection.

Their new molecules are housed on a testing strip. After being contacted with infected bodily fluids, the strip is connected to a computer monitor that displays a clear range of electrochemical responses demonstrating the severity of an infection.

"The signs and symptoms people demonstrate aren't always reflective of the level of the infection they have," McHardy said. "This device could very easily show just how serious an infection is and make diagnosis a much quicker process, possibly preventing a more serious illness."

Gorski believes the method could be especially useful to people who have just undergone surgery, as it could determine definitively whether they have an infection from the procedure before it worsens.

Read more at Science Daily

Making mistakes while studying actually helps you learn better

When learning something new, there are instances where trial and error helps rather than hinders, according to recent findings by Baycrest researchers.

Contrary to popular belief, when a person makes a mistake while learning, it improves their memory for the right information, but only if the error is close to the correct answer, according to a study published in the journal, Memory.

"Our research found evidence that mistakes that are a 'near miss' can help a person learn the information better than if no errors were made at all," says Dr. Nicole Anderson, senior author on the paper and senior scientist at Baycrest's Rotman Research Institute. "These types of errors can serve as stepping stones to remembering the right answer. But if the error made is a wild guess and out in left field, then a person does not learn the correct information as easily."

These findings could help with improving education for not only younger adults, but also late-life learners.

In one of the studies reported in the paper, researchers recruited 32 young adults with no Spanish background to guess the English definition of certain Spanish words. The Spanish words selected either resembled an English word with a similar meaning (such as careera, which means degree) or the word looked like an English word, but meant something different (such as carpeta, which resembles carpet, but means folder).

Participants were shown the Spanish words and asked to guess its meaning. Then, they were briefly shown the correct translation, before being shown another Spanish word. After repeating this process with 16 Spanish words, participants had a short break before their memory for the translations was tested.

Researchers found that people were better able to remember the correct translations for Spanish words that were similar to the English word. They had greater difficulty recalling the meaning for words that looked misleading.

"Based on these findings, someone studying for an exam should only take practice quizzes after reviewing the material," says Dr. Anderson, who is also an associate professor of psychology and psychiatry at the University of Toronto. "If a person takes a practice test and is unfamiliar with the content, they risk making guesses that are nowhere near the right answer. This could make it harder for them to learn the correct information later."

Even if a person makes a mistake while testing themselves, as long as their error is close to the right answer, they're more likely to remember the right information, adds Dr. Anderson.

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Volcanic activity, declining ocean oxygen triggered mass extinction of ancient organisms

Postdoctoral Fellow Theodore Them (left, holding an extinct fossil sample) and Assistant Professor Jeremy Owens (right, holding a rock core sample). The researchers used the samples to study the global record of oxygenation.

Global climate change, fueled by skyrocketing levels of atmospheric carbon dioxide, is siphoning oxygen from today's oceans at an alarming pace -- so fast that scientists aren't entirely sure how the planet will respond.

Their only hint? Look to the past.

In a study to be published this week in the journal Proceedings of the National Academy of Sciences, researchers from Florida State University did just that -- and what they found brings into stark relief the disastrous effects a deoxygenated ocean could have on marine life.

Millions of years ago, scientists discovered, powerful volcanoes pumped Earth's atmosphere full of carbon dioxide, draining the oceans of oxygen and driving a mass extinction of marine organisms.

"We want to understand how volcanism, which can be related to modern anthropogenic carbon dioxide release, manifests itself in ocean chemistry and extinction events," said study co-author Jeremy Owens, an assistant professor in FSU's Department of Earth, Ocean and Atmospheric Science. "Could this be a precursor to what we're seeing today with oxygen loss in our oceans? Will we experience something as catastrophic as this mass extinction event?"

For this study, an international team of scientists set out to better understand today's oxygen-deprived oceans by investigating the Toarcian Oceanic Anoxic Event (T-OAE), an interval of global oceanic deoxygenation characterized by a mass extinction of marine organisms that occurred in the Early Jurassic Period.

"We wanted to reconstruct Early Jurassic ocean oxygen levels to better understand the mass extinction and the T-OAE," said Theodore Them, a postdoctoral researcher at FSU who led the study. "We used to think of ocean temperature and acidification as a one-two punch, but more recently we've learned this third variable, oxygen change, is equally important."

By analyzing the thallium isotope composition of ancient rocks from North America and Europe, the team found that ocean oxygen began to deplete well before the defined time interval traditionally ascribed to the T-OAE.

That initial deoxygenation, researchers say, was precipitated by massive episodes of volcanic activity -- a process not altogether unlike the industrial emission of carbon dioxide we're familiar with today.

"Over the past 50 years, we've seen that a significant amount of oxygen has been lost from our modern oceans," Them said. "While the timescales are different, past volcanism and carbon dioxide increases could very well be an analog for present events."

When the atmosphere is suffused with carbon dioxide, global temperatures climb, triggering a cascade of hydrological, biological and chemical events that conspire to sap the oceans of oxygen.

Scientists have found evidence that several hundred thousand years before the T-OAE, volcanoes flooded Earth's atmosphere with carbon dioxide, helping to set in motion the sequence of events that would ultimately result in oceanic deoxygenation and widespread marine life extinction.

While researchers have long surmised a link between volcanism, loss of oxygen and mass extinction, this study provides the first conclusive data.

"As a community, we've suggested that sediments deposited during the T-OAE were indicative of widespread oxygen loss in the oceans, but we've never had the data until now," Them said.

Prehistorical examples of carbon dioxide deluges and suffocating oceanic deoxygenation provide a lesson in how Earth systems respond to a variable climate.

This analysis of the T-OAE, and the onset of deoxygenation that preceded it, is another in a lineage of reports that presage a bleak future for oceans with diminishing levels of oxygen.

"It's extremely important to study these past events," Them said. "It seems that no matter what event we observe in Earth's history, when we see carbon dioxide concentrations increasing rapidly, the result tends to be very similar: a major or mass extinction event. This is another situation where we can unequivocally link widespread oceanic deoxygenation to a mass extinction."

Steps can still be taken to curb oxygen loss in the modern oceans. For example, conserving important wetlands and estuaries -- along with other environments that absorb and store large amounts of carbon dioxide -- could help to blunt the effects of harmful industrial emissions.

But should our oceans' oxygen contents continue to decline at their current rates, future marine organisms could be doomed to the same fate that befell their Jurassic ancestors.

"If you're an oxygen-consuming organism, you don't want to see major changes in marine oxygen levels," Them said. "You either adapt or go extinct."

Read more at Science Daily

Experiments trace interstellar dust back to solar system's formation

This cometary-type interplanetary dust particle was collected by a NASA stratospheric aircraft. Its porous aggregate structure is evident in this scanning electron microscope image.

Note: This press release was adapted from an original release by the University of Hawaii at Manoa in Honolulu.

Experiments conducted at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) helped to confirm that samples of interplanetary particles -- collected from Earth's upper atmosphere and believed to originate from comets -- contain dust leftover from the initial formation of the solar system.

An international team, led by Hope Ishii, a researcher at the University of Hawaii at Manoa (UH Manoa), studied the particles' chemical composition using infrared light at Berkeley Lab's Advanced Light Source (ALS). Scientists also explored their nanoscale chemical makeup using electron microscopes at the Lab's Molecular Foundry, which specializes in nanoscale R&D, and at the University of Hawaii's Advanced Electron Microscopy Center.

The study was published online June 11 in the journal Proceedings of the National Academy of Sciences.

The initial solids from which the solar system formed consisted almost entirely of carbon, ices, and disordered (amorphous) silicate, the team concluded. This dust was mostly destroyed and reworked by processes that led to the formation of planets. Surviving samples of pre-solar dust are most likely to be preserved in comets -- small, cold bodies that formed in the outer solar nebula.

In a relatively obscure class of these interplanetary dust particles believed to originate from comets, there are tiny glassy grains called GEMS (glass embedded with metal and sulfides) that are typically only tens to hundreds of nanometers in diameter, or less than a hundredth of the thickness of a human hair. Researchers embedded the sample grains in an epoxy that was cut into thin slices for the various experiments.

Using transmission electron microscopy at the Molecular Foundry, the research team made maps of the element distributions and discovered that these glassy grains are made up of subgrains that aggregated together in a different environment prior to the formation of the comet.

The nanoscale GEMS subgrains are bound together by dense organic carbon in clusters comprising the GEMS grains. These GEMS grains were later glued together with other components of the cometary dust by a distinct, lower-density organic carbon matrix.

The types of carbon that rim the subgrains and that form the matrix in these particles decompose with even weak heating, suggesting that the GEMS could not have formed in the hot inner solar nebula, and instead formed in a cold, radiation-rich environment, such as the outer solar nebula or pre-solar molecular cloud.

Jim Ciston, a staff scientist at the Molecular Foundry, said the particle-mapping process of the microscopy techniques provided key clues to their origins. "The presence of specific types of organic carbon in both the inner and outer regions of the particles suggests the formation process occurred entirely at low temperatures," he said.

"Therefore, these interplanetary dust particles survived from the time before formation of the planetary bodies in the solar system, and provide insight into the chemistry of those ancient building blocks."

He also noted that the "sticky" organics that covered the particles may be a clue to how these nanoscale particles could gather into larger bodies without the need for extreme heat and melting.

Ishii, who is based at the UH Manoa's Hawaii Institute of Geophysics and Planetology, said, "Our observations suggest that these exotic grains represent surviving pre-solar interstellar dust that formed the very building blocks of planets and stars. If we have at our fingertips the starting materials of planet formation from 4.6 billion years ago, that is thrilling and makes possible a deeper understanding of the processes that formed and have since altered them."

Hans Bechtel, a research scientist in the Scientific Support Group at Berkeley Lab's ALS, said that the research team also employed infrared spectroscopy at the ALS to confirm the presence of organic carbon and identify the coupling of carbon with nitrogen and oxygen, which corroborated the electron microscopy measurements.

The ALS measurements provided micron-scale (millionths of a meter) resolution that gave an average of measurements for entire samples, while the Molecular Foundry's measurements provided nanometer-scale (billionths of a meter) resolution that allowed scientists to explore tiny portions of individual grains.

Read more at Science Daily

Genome-editing tool could increase cancer risk

Therapeutic use of gene editing with the so-called CRISPR-Cas9 technique may inadvertently increase the risk of cancer, according to a new study from Karolinska Institutet, Sweden, and the University of Helsinki, Finland, published in Nature Medicine. Researchers say that more studies are required in order to guarantee the safety of these 'molecular scissors' for gene-editing therapies.

CRISPR-Cas9 is a molecular machine first discovered in bacteria that can be programmed to go to an exact place in the genome, where it cuts the DNA. These precise 'molecular scissors' can be used to correct faulty pieces of DNA and are currently being used in clinical trials for cancer immunotherapy in the US and China. New trials are expected to be launched soon so as to treat inherited blood disorders such as sickle cell anemia.

Two independent articles published in the journal Nature Medicine now report that therapeutic application of the genome-editing tool may, in fact, increase the risk of cancer. In one of the studies, scientists from Karolinska Institutet and the University of Helsinki report that use of CRISPR-Cas9 in human cells in a laboratory setting can activate a protein known as p53, which acts as a cell's 'first aid kit' for DNA breaks. Once active, p53 reduces the efficiency of CRISPR-Cas9 gene editing. Thus, cells that do not have p53 or are unable to activate it show better gene editing. Unfortunately, however, lack of p53 is also known to contribute to making cells grow uncontrollably and become cancerous.

"By picking cells that have successfully repaired the damaged gene we intended to fix, we might inadvertently also pick cells without functional p53," says Dr Emma Haapaniemi, researcher at the Department of Medicine at Karolinska Institutet in Huddinge and co-first author of the study. "If transplanted into a patient, as in gene therapy for inherited diseases, such cells could give rise to cancer, raising concerns for the safety of CRISPR-based gene therapies."

"CRISPR-Cas9 is a powerful tool with staggering therapeutic potential," adds Dr Bernhard Schmierer, researcher at the Department of Medical Biochemistry and Biophysics at Karolinska Institutet, and Head of the High Throughput Genome Engineering Facility of Science for Life Laboratory (SciLifeLab), who co-supervised the study. "Like all medical treatments however, CRISPR-Cas9-based therapies might have side effects, which the patients and caregivers should be aware of. Our study suggests that future work on the mechanisms that trigger p53 in response to CRISPR-Cas9 will be critical in improving the safety of CRISPR-Cas9-based therapies."

From Science Daily

Discovery of the oldest mammal in Brazil pays tribute to David Bowie

Brasilestes stardusti existed more than 70 million years ago in what is now São Paulo State. Its description is based on a fossilized tooth.

Brasilestes stardusti is the name given to the oldest known mammal found in Brazil. It lived in what is now the northwest of São Paulo State at the end of the Mesozoic Era between 87 million and 70 million years ago. It is the only Brazilian mammal known to have coexisted with the dinosaurs.

The discovery of Brasilestes was announced on May 30, 2018, by a team led by Max Langer, a professor at the University of São Paulo's Ribeirão Preto School of Philosophy, Science & Letters (FFCLRP-USP). Langer's team included colleagues at the Federal University of Goiás and the University of Campinas in Brazil, La Plata Museum in Argentina, and the Massachusetts Institute of Technology (MIT) in the US.

Physically speaking, Brasilestes consists of a fossilized premolar tooth with a maximum crown length of 3.5 mm. "The tooth is small and incomplete: the roots are missing," said paleontologist Mariela Cordeiro de Castro, first author of the paper recently published in Royal Society Open Science.

"Small but not tiny," Castro continued. "Although it's only 3.5 mm, the Brasilestes tooth is three times bigger than all known Mesozoic mammal teeth. In the age of the dinosaurs, most mammals were the size of mice. Brasilestes was far larger, about the size of an opossum."

The name of the new species pays tribute to British rock star David Bowie, who died in January 2016, a month after the fossil was found. Brasilestes stardusti alludes to Ziggy Stardust, an extraterrestrial character created by Bowie for a 1972 album.

The research was supported by the São Paulo Research Foundation -- FAPESP as part of the thematic project "The origin and rise of dinosaurs in Gondwana (late Triassic-early Jurassic)" , for which Langer is principal investigator.

The fossilized tooth was found in a rocky outcrop of the Adamantina Formation in General Salgado, São Paulo State. The rocks are in a field on a ranch called Fazenda Buriti.

"We were visiting Mesozoic outcrops when Júlio Marsola [another member of the team], keen-sighted as a lynx, spotted a small tooth sticking up out of a rock," said Castro, a professor at the Federal University of Goiás (UFG).

"The General Salgado deposits are well-known. Several Mesozoic crocodiles have come from them. The particular outcrop where I found Brasilestes is interesting, with dozens of fragments of Mesozoic crocodile eggshells. I bent down to look more closely at a small part of the outcrop to see if there were any eggshells and spotted the tooth. If it had stayed out in the open like that for a few more days, the rain would have swept it away.

"When I noticed what appeared to resemble the base of the tooth's two roots [the roots themselves have broken off], I thought it must be a mammal. Laboratory analysis gave us the certainty that it is indeed from a mammal."

A placental mammal in the Botucatu Desert

While a mere 3.5 mm tooth, especially an incomplete one, may seem insufficient to describe a new species of mammal, in actual, fact extinct mammals are frequently described on the basis of a single fossilized tooth.

This is because teeth are the most durable part of the mammalian skeleton. After all, they have to withstand the wear and tear of chewing for an entire lifetime. In contrast, many fish species and reptiles, for example, grow new teeth continually throughout their lives. Indeed, mammalian teeth are often the only skeletal remains that stay intact long enough to become fossilized.

The fact that a single premolar is all that is left of Brasilestes and that it is incomplete prevented the researchers from distinguishing with absolute confidence the group of mammals to which the species belonged. They know the tooth belonged to a therian, a member of a large subclass of Mammalia that includes marsupials and placentals.

Although there is not enough evidence to support the inclusion of Brasilestes in either infraclass, the researchers believe (but cannot categorically conclude) it was a placental mammal. If so, the fossil is unique.

Today, there are three major groups of mammals, namely, placentals, marsupials and monotremes. All three evolved during the Mesozoic Era. At that time, however, they were by no means the only groups of mammals. There were also multituberculates, which were common in the northern hemisphere, as well as groups typical of the southern hemisphere such as meridiolestids and gondwanatherians -- named for Gondwana, the ancient southern supercontinent that gave rise to Africa, South America, Australia, Antarctica, and India.

The first Mesozoic mammal fossils were found in Argentinian Patagonia in the early 1980s, and some 30 species are now known. Until the Brasilestes announcement, these were the only ones found in South America. None remotely resembles the little tooth found in Brazil.

"When I showed the Brasilestes fossil to Edgardo Ortiz-Jaureguizar, a paleontologist at La Plata Museum, he was very surprised. He said he'd never seen anything like it, and at once showed it to another specialist at the same institution, Francisco Goin, who had the same reaction. Goin said Brasilestes resembled no other Mesozoic mammal found in Argentina, hence in South America," Castro recalled.

Among the 30-odd Argentinian species of Mesozoic mammals, there are meridiolestids, gondwanatherians, and even a few suspected multituberculates. There are no marsupials or placentals. The only fossils in these two groups found in South America date from after the mass extinction that wiped out the dinosaurs 66 million years ago in an event that marks the end of the Mesozoic and the onset of the current geological era, the Cenozoic.

Until the discovery of Brasilestes, the only traces of Mesozoic mammals in Brazil were hundreds of tracks and footprints left by unknown creatures 130 million years ago as they traversed the dunes of the Botucatu Desert in what is now São Paulo State. The solidified surface of those dunes has been preserved as sandstone slabs on which the footprints can be seen.

In 1993, Reinaldo José Bertini , a professor at São Paulo State University (UNESP) in Rio Claro, announced the discovery of a mammalian jawbone fragment with a single tooth far smaller than the Brasilestes premolar. However, Bertini did not publish a detailed study of the fossil and therefore could not name a new species.

"Brasilestes is not just the first Brazilian Mesozoic mammal to be described but also one of the few Mesozoic mammals found in more central regions of South America. The Argentinian fossils were found in geological formations in Patagonia, the southern tip of the continent," Langer said.

"Furthermore, Brasilestes is different from everything found before, suggesting that possibly placental mammals inhabited South America between 87.8 million and 70 million years ago," said the FAPESP thematic project coordinator.

New species possibly related to a mammal from India

Even more surprisingly, the Mesozoic mammal with premolars that most resemble the Brasilestes tooth lived on the other side of the world, in India, between 70 million and 66 million years ago. Its name is Deccanolestes. No other creature in the global fossil record is so similar to Brasilestes.

How could two members of the same lineage have lived so far apart in unconnected regions? Approximately 100 million years ago, when South America and Africa had only just been separated by the opening of the South Atlantic, India was breaking away from Gondwana and starting to wander through the Indian Ocean.

This implies that at least 100 million years ago, the ancestors of Brasilestes and Deccanolestes populated the Gondwana supercontinent. In other words, the lineage to which Brasilestes and Deccanolestes belong is far older than the ages of their fossils -- between 87 million and 70 million years ago for Brasilestes, and between 70 million and 66 million for Deccanolestes.

"The discovery of Brasilestes raises many more questions than answers about the biogeography of South American Mesozoic mammals," Langer said. "Thanks to Brasilestes, we've realized that the history of Gondwana's mammals is more complex than we thought."

Finding triggers speculation on xenarthrans' origins

This could give rise to new hypotheses and new lines of investigation. Who knows, for example, whether future research inspired by the discovery of Brasilestes will reveal the origin of a typical South American group, the xenarthrans, the order of armadillos, anteaters and sloths? Castro's main research interest, in fact, is the evolutionary history of the xenarthrans.

"An interesting feature of the Brasilestes premolar is its superthin enamel, which is only 20 micrometers thick. The Brasilestes enamel is the thinnest of any Cretaceous mammal in the fossil record. Most Mesozoic mammals have enamel in the range of 100 to 300 micrometers," Castro said.

"Tens of known species of xenarthrans are alive now. Hundreds are extinct. Only three have enamel. The microstructure of Brasilestes' premolar enamel is very similar to that of the nine-banded armadillo," said the FAPESP-supported researcher.

According to Castro, "molecular clock evidence suggests the xenarthran lineage started at least 85 million years ago. However, the oldest armadillo fossils, found in Rio de Janeiro, are about 50 million years old."

While it is intriguing to imagine Brasilestes as an ancient xenarthran, it is far too soon for any such affirmation.

"The age and provenance of Brasilestes do match molecular hypotheses for the origin of the xenarthrans, but it would be premature to infer taxonomic affinity in light of the morphological differences between the Brasilestes tooth and armadillo teeth," Castro said.

Langer agreed. "We have only one Brasilestes fossil. That's nowhere near enough to extract conclusions from the fossil record," he said.

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Pandoravirus: Giant viruses invent their own genes

This is Pandoravirus quercus, found in Marseille, France. Thin section, viewed via electron microscopy. Scale bar: 100 nm.

Three new members have been isolated and added to the Pandoravirus family by researchers at the Structural and Genomic Information Laboratory (CNRS/Aix?Marseille Université), working with partners at the Large Scale Biology Laboratory (CEA/Inserm/Université Grenoble?Alpes) and at CEA-Genoscope. This strange family of viruses, with their giant genomes and many genes with no known equivalents, surprised the scientists when they were discovered a few years ago. In the 11 June 2018 edition of Nature Communications, researchers offer an explanation: pandoviruses appear to be factories for new genes -- and therefore new functions. From freaks of nature to evolutionary innovators, giant viruses continue to shake branches on the tree of life!

In 2013, the discovery of two giant viruses unlike anything seen before blurred the line between the viral and cellular world. Pandoraviruses are as big as bacteria, and contain genomes that are more complex than those found in some eukaryotic organisms. Their strange amphora shape and enormous, atypical genome led scientists to wonder where they came from.

The same team has since isolated three new members of the family in Marseille, continental France, Nouméa, New Caledonia, and Melbourne, Australia. With another virus found in Germany, the team compared those six known cases using different approaches. Analyses showed that despite having very similar shapes and functions, these viruses only share half of their genes coding for proteins. Usually, however, members of the same family have more genes in common.

Furthermore, these new members contain a large number of orphan genes, i.e. genes which encode proteins that have no equivalent in other living organisms (this was already the case for the two previously discovered pandoraviruses). This unexplained characteristic is at the heart of many a debate over the origin of viruses. What most surprised researchers was that the orphan genes differed from one pandoravirus to another, making it less and less likely that they were inherited from a common ancestor!

Bioinformatic analysis showed that these orphan genes exhibit features very similar to those of non-coding (or intergenic) regions in the pandoravirus genome. Findings indicate the only possible explanation for the gigantic size of pandoravirus genomes, their diversity and the large proportion of orphan genes they contain: most of these viruses' genes may originate spontaneously and randomly in intergenic regions. In this scenario, genes "appear" in different locations from one strain to another, thus explaining their unique nature.

Read more at Science Daily

Diamond dust shimmering around distant stars

This is an artist impression of nanoscale diamonds surrounding a young star in the Milky Way. Recent GBT and ATCA observations have identified the telltale radio signal of diamond dust around 3 such stars, suggesting they are a source of the so-called anomalous microwave emission.

For decades, astronomers have puzzled over the exact source of a peculiar type of faint microwave light emanating from a number of regions across the Milky Way. Known as anomalous microwave emission (AME), this light comes from energy released by rapidly spinning nanoparticles -- bits of matter so small that they defy detection by ordinary microscopes. (The period on an average printed page is approximately 500,000 nanometers across.)

"Though we know that some type of particle is responsible for this microwave light, its precise source has been a puzzle since it was first detected nearly 20 years ago," said Jane Greaves, an astronomer at Cardiff University in Wales and lead author on a paper announcing this result in Nature Astronomy.

Until now, the most likely culprit for this microwave emission was thought to be a class of organic molecules known as polycyclic aromatic hydrocarbons (PAHs) -- carbon-based molecules found throughout interstellar space and recognized by the distinct, yet faint infrared (IR) light they emit. Nanodiamonds -- particularly hydrogenated nanodiamonds, those bristling with hydrogen-bearing molecules on their surfaces -- also naturally emit in the infrared portion of the spectrum, but at a different wavelength.

A series of observations with the National Science Foundation's Green Bank Telescope (GBT) in West Virginia and the Australia Telescope Compact Array (ATCA) has -- for the first time -- homed in on three clear sources of AME light, the protoplanetary disks surrounding the young stars known as V892 Tau, HD 97048, and MWC 297. The GBT observed V892 Tau and the ATCA observed the other two systems.

"This is the first clear detection of anomalous microwave emission coming from protoplanetary disks," said David Frayer a coauthor on the paper and astronomer with the Green Bank Observatory.

The astronomers also note that the infrared light coming from these systems matches the unique signature of nanodiamonds. Other protoplanetary disks throughout the Milky Way, however, have the clear infrared signature of PAHs yet show no signs of the AME light.

This strongly suggests that PAHs are not the mysterious source of anomalous microwave radiation, as astronomers once thought. Rather, hydrogenated nanodiamonds, which form naturally within protoplanetary disks and are found in meteorites on Earth, are the most likely source of AME light in our galaxy.

"In a Sherlock Holmes-like method of eliminating all other causes, we can confidently say the best candidate capable of producing this microwave glow is the presence of nanodiamonds around these newly formed stars," said Greaves. Based on their observations, the astronomers estimate that up to 1-2 percent of the total carbon in these protoplanetary disks has gone into forming nanodiamonds.

Evidence for nanodiamonds in protoplanetary disks has grown over the past several decades. This is, however, the first clear connection between nanodiamonds and AME in any setting.

Statistical models also strongly support the premise that nanodiamonds are abundant around infant stars and are responsible for the anomalous microwave emission found there. "There is a one in 10,000 chance, or less, that this connection is due to chance," said Frayer.

For their research, the astronomers used the GBT and ATCA to survey 14 young stars across the Milky Way for hints of anomalous microwave emission. AME was clearly seen in 3 of the 14 stars, which are also the only 3 stars of the 14 that show the IR spectral signature of hydrogenated nanodiamonds. "In fact, these are so rare," notes Greaves, "no other young stars have the confirmed infrared imprint."

This detection has interesting implications for the study of cosmology and the search for evidence that our universe began with a period of inflation. If immediately after the Big Bang, our universe grew at a pace that vastly outstripped the speed of light, a trace of that period of inflation should be seen in a peculiar polarization of the cosmic microwave background. Though this signature of polarization has yet to be conclusively detected, the work by Greaves and her colleagues offers some hope that it could be.

"This is good news for those who study polarization of the cosmic microwave background, since the signal from spinning nanodiamonds would be weakly polarized at best," said Brian Mason, an astronomer at the National Radio Astronomy Observatory and coauthor on the paper. "This means that astronomers can now make better models of the foreground microwave light from our galaxy, which must be removed to study the distant afterglow of the Big Bang."

Nanodiamonds likely form out of a superheated vapor of carbon atoms in highly energized star-forming regions. This is not unlike industrial methods of creating nanodiamonds on Earth.

In astronomy, nanodiamonds are special in that their structure produces what is known as a "dipole moment" -- an arrangement of atoms that allows them to emit electromagnetic radiation when they spin. Because these particles are so small -- smaller than normal dust particles in a protoplanetary disk -- they are able to spin exceptionally fast, emitting radiation in the microwave range rather than in the meter-wavelength range, where galactic and intergalactic radiation would probably drown it out.

"This is a cool and unexpected resolution to the puzzle of anomalous microwave radiation," concluded Greaves. "It's even more interesting that it was obtained by looking at protoplanetary disks, shedding light on the chemical features of early solar systems, including our own."

"It is an exciting result," concluded co-author Anna Scaife from Manchester University. "It's not often you find yourself putting new words to famous tunes, but 'AME in the Sky with Diamonds' seems a thoughtful way of summarizing our research."

Read more at Science Daily

New system recovers fresh water from power plants

The team’s lab setup was used to test the powerplant condenser system. The mesh is placed above the funnel at right to collect the water that condenses on the mesh.

A new system devised by MIT engineers could provide a low-cost source of drinking water for parched cities around the world while also cutting power plant operating costs.

About 39 percent of all the fresh water withdrawn from rivers, lakes, and reservoirs in the U.S. is earmarked for the cooling needs of electric power plants that use fossil fuels or nuclear power, and much of that water ends up floating away in clouds of vapor. But the new MIT system could potentially save a substantial fraction of that lost water -- and could even become a significant source of clean, safe drinking water for coastal cities where seawater is used to cool local power plants.

The principle behind the new concept is deceptively simple: When air that's rich in fog is zapped with a beam of electrically charged particles, known as ions, water droplets become electrically charged and thus can be drawn toward a mesh of wires, similar to a window screen, placed in their path. The droplets then collect on that mesh, drain down into a collecting pan, and can be reused in the power plant or sent to a city's water supply system.

The system, which is the basis for a startup company called Infinite Cooling that last month won MIT's $100K Entrepreneurship Competition, is described in a paper published today in the journal Science Advances, co-authored by Maher Damak PhD '17 and associate professor of mechanical engineering Kripa Varanasi. Damak and Varanasi are among the co-founders of the startup.

Varanasi's vision was to develop highly efficient water recovery systems by capturing water droplets from both natural fog and plumes of industrial cooling towers. The project began as part of Damak's doctoral thesis, which aimed to improve the efficiency of fog-harvesting systems that are used in many water-scarce coastal regions as a source of potable water. Those systems, which generally consist of some kind of plastic or metal mesh hung vertically in the path of fogbanks that regularly roll in from the sea, are extremely inefficient, capturing only about 1 to 3 percent of the water droplets that pass through them. Varanasi and Damak wondered if there was a way to make the mesh catch more of the droplets -- and found a very simple and effective way of doing so.

The reason for the inefficiency of existing systems became apparent in the team's detailed lab experiments: The problem is in the aerodynamics of the system. As a stream of air passes an obstacle, such as the wires in these mesh fog-catching screens, the airflow naturally deviates around the obstacle, much as air flowing around an airplane wing separates into streams that pass above and below the wing structure. These deviating airstreams carry droplets that were heading toward the wire off to the side, unless they were headed bang-on toward the wire's center.

The result is that the fraction of droplets captured is far lower than the fraction of the collection area occupied by the wires, because droplets are being swept aside from wires that lie in front of them. Just making the wires bigger or the spaces in the mesh smaller tends to be counterproductive because it hampers the overall airflow, resulting in a net decrease in collection.

But when the incoming fog gets zapped first with an ion beam, the opposite effect happens. Not only do all of the droplets that are in the path of the wires land on them, even droplets that were aiming for the holes in the mesh get pulled toward the wires. This system can thus capture a much larger fraction of the droplets passing through. As such, it could dramatically improve the efficiency of fog-catching systems, and at a surprisingly low cost. The equipment is simple, and the amount of power required is minimal.

Next, the team focused on capturing water from the plumes of power plant cooling towers. There, the stream of water vapor is much more concentrated than any naturally occurring fog, and that makes the system even more efficient. And since capturing evaporated water is in itself a distillation process, the water captured is pure, even if the cooling water is salty or contaminated. At this point, Karim Khalil, another graduate student from Varanasi's lab joined the team.

"It's distilled water, which is of higher quality, that's now just wasted," says Varanasi. "That's what we're trying to capture." The water could be piped to a city's drinking water system, or used in processes that require pure water, such as in a power plant's boilers, as opposed to being used in its cooling system where water quality doesn't matter much.

A typical 600-megawatt power plant, Varanasi says, could capture 150 million gallons of water a year, representing a value of millions of dollars. This represents about 20 to 30 percent of the water lost from cooling towers. With further refinements, the system may be able to capture even more of the output, he says.

What's more, since power plants are already in place along many arid coastlines, and many of them are cooled with seawater, this provides a very simple way to provide water desalination services at a tiny fraction of the cost of building a standalone desalination plant. Damak and Varanasi estimate that the installation cost of such a conversion would be about one-third that of a building a new desalination plant, and its operating costs would be about 1/50. The payback time for installing such a system would be about two years, Varanasi says, and it would have essentially no environmental footprint, adding nothing to that of the original plant.

"This can be a great solution to address the global water crisis," Varanasi says. "It could offset the need for about 70 percent of new desalination plant installations in the next decade."

In a series of dramatic proof-of-concept experiments, Damak, Khalil, and Varanasi demonstrated the concept by building a small lab version of a stack emitting a plume of water droplets, similar to those seen on actual power plant cooling towers, and placed their ion beam and mesh screen on it. In video of the experiment, a thick plume of fog droplets is seen rising from the device -- and almost instantly disappears as soon as the system is switched on.

The team is currently building a full-scale test version of their system to be placed on the cooling tower of MIT's Central Utility Plant, a natural-gas cogeneration power plant that provides most of the campus' electricity, heating, and cooling. The setup is expected to be in place by the end of the summer and will undergo testing in the fall. The tests will include trying different variations of the mesh and its supporting structure, Damak says.

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Hurricanes are slowing down, and that's bad news

Flooded Las Olas Blvd and Palm trees blowing in the winds, catastrophic hurricane Irma.

Some hurricanes are moving more slowly, spending increased time over land and leading to catastrophic local rainfall and flooding, according to a new study published Wednesday (June 6) in the journal Nature.

While hurricanes batter coastal regions with destructive wind speeds, study author James Kossin says the speed at which hurricanes track along their paths -- their translational speed -- can also play a role in the damage and devastation they cause. Their movement influences how much rain falls in a given area.

This is especially true as global temperatures increase.

"Just a 10 percent slowdown in hurricane translational speed can double the increase in rainfall totals caused by 1 degree Celsius of global warming," says Kossin, a researcher at the National Oceanic and Atmospheric Administration's (NOAA) Center for Weather and Climate. He is based at the University of Wisconsin-Madison.

The study compared 68 years (1949-2016) of worldwide hurricane track and intensity data, known as best-track data, from NOAA to identify changes in translational speeds. It found that, worldwide, hurricane translational speeds have averaged a 10 percent slowdown in that time.

One recent storm highlights the potential consequences of this slowing trend. In 2017, Hurricane Harvey stalled over eastern Texas rather than dissipating over land, as hurricanes tend to do. It drenched Houston and nearby areas with as much as 50 inches of rain over several days, shattering historic records and leaving some areas under several feet of water.

How much hurricanes have slowed depends on where they occur, Kossin found. "There is regional variation in the slowdown rates when looking at the 10 percent global average across the same time frame," he says.

The most significant slowdown, 20 percent, occurred in the Western North Pacific Region, an area that includes Southeast Asia. Nearby, in the Australian Region, Kossin identified a reduction of 15 percent. In the North Atlantic Region, which includes the U.S., Kossin found a 6 percent slowdown in the speeds at which hurricanes move.

When further isolating the analysis to hurricane speeds over land, where their impact is greatest, Kossin found that slowdown rates can be even greater. Hurricanes over land in the North Atlantic have slowed by as much as 20 percent, and those in the Western North Pacific as much as 30 percent.

Kossin attributes this, in part, to the effects of climate change, amplified by human activity. Hurricanes move from place to place based on the strength of environmental steering winds that push them along. But as the Earth's atmosphere warms, these winds may weaken, particularly in places like the tropics, where hurricanes frequently occur, leading to slower-moving storms.

Additionally, a warmer atmosphere can hold more water vapor, potentially increasing the amount of rain a hurricane can deliver to an area.

The study complements others that demonstrate climate change is affecting hurricane behavior.

For instance, in 2014, Kossin showed that hurricanes are reaching their maximum intensities further from the tropics, shifting toward the poles in both the Northern and Southern Hemispheres. These shifts can deliver hurricanes to areas -- including some heavily populated coastal regions -- that have not historically dealt with direct hits from storms and the devastating losses of life and property that can result.

Another study, published in April by researchers at the National Center for Atmospheric Research, used a modeling approach to look at what would happen to hurricanes under future climate projections. Using real hurricane data from 2000-2013, the researchers found future hurricanes will experience a 9 percent slowdown, higher wind speeds, and produce 24 percent more rainfall.

Read more at Science Daily