Chemical transformations in minerals deep beneath the seafloor could explain why Indonesia’s 2004 mega-earthquake was unexpectedly destructive, researchers report in the May 26 Science.
The magnitude 9.2 quake and the tsunami that it triggered killed more than 250,000 people, flattened villages, and swept homes out to sea across Southeast Asia. It was one of the deadliest tsunamis in recorded history.
“It raised a whole bunch of questions, because that wasn’t a place in the world where we thought a magnitude 9 earthquake would occur,” says study coauthor Brandon Dugan, a geophysicist at the Colorado School of Mines in Golden.
The thick but stable layer of sediment where tectonic plates meet off the coast of the Indonesian island of Sumatra should have limited the power of an earthquake, seismologists had predicted. But instead, this quake was the third-strongest on record worldwide. Dugan spent two months aboard a boat with 30 other scientists collaborating through the International Ocean Discovery Program. The researchers drilled down 1,500 meters below the seafloor in two places off the coast of Sumatra, extracting narrow cylinders of sediment. This sediment is very slowly moving toward the fault where the 2004 earthquake occurred — a zone where one massive tectonic plate slides over another, pushing that plate downward.
Analyzing how sediment changes with depth can give scientists a snapshot of the geological processes at play near the fault zone.
In particular, deep down, the researchers identified a layer of sediment where the water had a lower salinity than the water in the sediment above or below. Since seawater seeping into the sediment would be salty, the evidence of freshwater suggests that the water must have instead been released from within minerals in the sediment.
For tens of millions of years, Dugan proposes, minerals sat on the seafloor taking in water — baking it into their crystal structure. Then, more sediment settled on top. It got toasty under such a thick blanket of sediment, heating up the minerals beneath. The temperature increase triggered a chemical transformation within the sediment, pushing water out of the mineral crystals and into tiny pores between the grains. The sediment sampled in this study is still dehydrating. By the time any of it reaches the plate boundary, Dugan says, it’ll be buried under kilometers of more sediment and will probably be completely dehydrated.
At first, the liberated water would have softened the material, actually decreasing the risk of a big earthquake by allowing it to absorb more force, Dugan says. As the sediment got closer to the fault over millions of years, though, the water flowed away, leaving it brittle and unstable — the perfect setup for a mega-quake.
The timing of this sediment dehydration process can make or break a quake. Had the sediment near the fault been in a softened state when the quake struck in 2004, the tremor might not have been as deadly, Dugan says. But since enough time had passed for it to become brittle again, the tectonic plates were able to rapidly slip past each other for a much greater distance during the quake. That massive motion displaced the seafloor itself, setting a tsunami into motion. “It’s really the tsunamis from these earthquakes that prove to be the deadliest and most dangerous,” says Roland Bürgmann, a seismologist at the University of California, Berkeley who wasn’t part of the study. And quakes that displace the seafloor are far more likely to trigger tsunamis.
The findings could apply to other faults with similarly thick sediment, such as the Cascadia Subduction Zone in the Pacific Northwest, suggests study coauthor Andre Hüpers, a geophysicist at the University of Bremen in Germany.
But more evidence is needed before applying such analysis to faults beyond this one, says Bürgmann. The argument for what happened along the Sumatran fault is compelling, he says. “But nonetheless, it’s only one data point. It doesn’t yet make for a pattern.”
The first thing you’ll notice is the noise. Monitors beep steadily, relentlessly, ready to sound a car-alarm blare if a baby is in trouble.
The air has an astringent odor — not clean exactly, but reminiscent of an operating room (there’s one next door). Ceiling lights shine fluorescent white. Half are off, but glare from the monitors throws out extra light. It’s midday on a Friday, but it’ll be just as bright at midnight.
Here on the fourth floor of Yale New Haven Children’s Hospital, 10 tiny beds hold 10 tiny infants, each with Band-Aid–like patches stuck to their bodies to continuously monitor health. Between beds, nurses squeeze through narrow aisles crammed with folding chairs and plastic incubators. This space, one of five in the hospital’s neonatal intensive care unit, has the people and equipment needed to keep sick babies alive — heart rate monitors, oxygen tanks, IV poles to deliver medications. Until recently, Yale’s NICU and hundreds like it across the country were considered the place to be for newborns withdrawing from opioid drugs. But now, as the number of drug-dependent babies surges, doctors here and elsewhere are searching for better options.
“We’re really focused on trying to get these kids out of the NICU,” says Yale pediatrician Matthew Grossman. “We’re looking at moms and the dads as the first line of treatment.”
The nationwide rate of babies withdrawing from opioids has soared — up nearly 400 percent from 2000 to 2012. The booming numbers are the bleak by-product of the United States’ ongoing battle with the drugs: Sales of prescription opioid pain relievers alone quadrupled from 1999 to 2010, and overdose deaths tripled from 2000 to 2014. When pregnant women use opioids, the drugs pass from bloodstream to baby. After exposure in the womb to Vicodin, methadone or heroin, for example, babies can become dependent. At birth, when the drug flow stops, babies can go through agonizing withdrawal — body shakes, intestinal problems, constant crying. The condition is known as neonatal abstinence syndrome, or NAS. But there’s no clear consensus on how to care for these struggling babies, Grossman says. Usually they’re whisked off to the NICU and treated with opioids. The drugs ease symptoms, but they prolong exposure to “really powerful and potentially dangerous medications,” he says.
At Yale, NAS babies used to spend weeks in the NICU — they still do in many U.S. hospitals. But in the last few years, Grossman and others have begun to question this method of care. Infants suffering from opioid withdrawal might actually do better back in parents’ arms, away from the high-tech hubbub. Comfort is key. Quiet, dark environments, swaddling, breastfeeding, rocking and holding, no unnecessary tests — it’s baby care 101.
That’s hard to do in the busy, loud NICU, says Grossman. Plus, there’s no place for parents to stay. They can visit, perched on folding chairs wedged between beds, says Yale pediatrician Rachel Osborn, but moms and dads “often feel like they’re extraneous and in the way.”
Faced with these and other obstacles, Grossman, Osborn and others are radically redefining their methods. They’re examining traditional practices, testing new ideas and getting back to basics. The results have been dramatic.
“We’re treating the families with respect and the babies like babies,” Grossman says. The parents have everything the baby needs, he says. “It’s not a whole lot more complicated than that.” State of alarm Maine, Vermont and West Virginia reported the highest rates of neonatal abstinence syndrome, opioid withdrawal linked to maternal drug use. Maine, Maryland, Massachusetts and Rhode Island rates are from 2012; the rest are 2013.
Click or tap the map below to learn more. Tough going Families today are much more likely to deal with opioid use — and its consequences for newborns — than they were a decade ago.
In 2004, NAS rates were consistently low across the country: For every 1,000 babies born, roughly one was diagnosed with NAS. By 2013, when pediatrician Nicole Villapiano and colleagues examined rural versus urban data, rates were up across the board. But rural areas had been hit the hardest, with nearly 8 per 1,000 babies diagnosed with NAS, the researchers reported in February in JAMA Pediatrics.
In an urban hospital near Rhode Island’s Providence River, Villapiano witnessed infant opioid withdrawal firsthand. She was first assigned to the newborn nursery service at Women and Infants Hospital in Providence in 2011. “I imagined it’d be a joyful time, seeing babies going off with their families, having wonderful lives.”
Reality quickly dashed that hopeful picture. On any given day, she might see several babies at a time struggling with withdrawal. “These children were miserable,” says Villapiano, now at the University of Michigan in Ann Arbor. “Their cries were persistent and their irritability was profound.”
NAS isn’t easy to define. Babies suffer a wide range of symptoms. They’re sweating, shaking, stiff. Stools are loose, eating and sleeping are difficult, and crankiness is common. Babies with NAS can also have breathing problems, seizures and low birth weights.
The syndrome was first described in heroin-exposed infants. Scientists now know that all sorts of opioids used during pregnancy can trigger the condition, including “maintenance” drugs like methadone or buprenorphine used to treat opioid addiction, and even painkillers commonly prescribed during pregnancy, such as codeine and hydrocodone.
Not all infants exposed to opioids in utero go through withdrawal — and exactly what conditions lead to NAS is still unclear. The particular opioid and how much a pregnant woman uses, whether she takes certain antidepressants and even the number of cigarettes she smokes per day all seem to factor in, Stephen Patrick of Vanderbilt University in Nashville and colleagues reported in Pediatrics in 2015. A nonsmoking woman on oxycodone for a few weeks, for example, might have roughly a 1 percent chance of delivering a baby with NAS. For a pack-a-day smoker on antidepressants and buprenorphine for six months, the risk could be more than 30 percent.
Because opioids are such a broad family of addictive drugs, opioid-using moms don’t fit neatly into one category, says Ju Lee Oei, a neonatologist at the University of New South Wales in Sydney. “We need to be aware that Mrs. Smith down the road who’s getting a bit of codeine for her back pain could have a baby with NAS,” Oei says. Some women give birth to NAS babies while recovering from opioid addiction — even though they’re doing everything doctors advise, says pediatrician Alison Holmes of Children’s Hospital at Dartmouth-Hitchcock in Lebanon, N.H.
“Sometimes people think, ‘Oh, these mothers are such horrible addicts,’ ” Holmes says. But a lot of the time, “they’re staying on their methadone, they’re staying on their buprenorphine, they’re keeping symptoms under control — but their babies are still going to withdraw.”
No one knows exactly what opioid exposure does to fetal brains, or how these kids will fare in the future. Certain brain regions may not grow correctly, previous studies have suggested. Children can also have vision trouble and may develop behavior and attention problems. One long-term Australian study published in February linked a diagnosis of NAS with poor academic performance — all the way up to age 12 or 13.
Whether that’s caused by NAS is hard to say, says Oei, a coauthor of the study. Poverty, poor childhood nutrition and prenatal exposure to alcohol or other drugs could also come into play. But the results are a red flag for all those newly diagnosed babies. “You expect your baby to go to school and get good grades,” Oei says. But from as early as third grade, “these kids don’t seem to be able to do that.”
Still, research on NAS outcomes and potential treatments remains full of gaps, a 2015 report from the U.S. Government Accountability Office found. And there’s no nationally accepted treatment protocol for NAS. “Everyone’s doing it their own way,” says Scott Wexelblatt, a pediatrician at Cincinnati Children’s Hospital Medical Center.
Time for a change The traditional way to assess NAS was published more than 40 years ago by neonatologist Loretta Finnegan, now at the College on Problems of Drug Dependence in Philadelphia. Every four to eight hours, sometimes more frequently, nurses evaluate symptoms using a detailed scoring list: the Finnegan Neonatal Abstinence Scoring System. Hit a certain score, and doctors will start up the withdrawal-easing opioids, typically morphine or methadone. But there’s a push and pull between managing withdrawal and dosing babies with more drugs, Wexelblatt says. “We don’t want to expose babies to opioids unless we really need to.”
Care of NAS babies varies widely in hospitals across the United States, according to a study in the May–June Academic Pediatrics. Some newborns may be getting too much opioids. To see if standardizing care could help infants get off the drugs faster, Wexelblatt and colleagues trained nurses on Finnegan scoring and outlined a detailed protocol for weaning.
That simple step made a big difference. Hospitals that adopted the protocol cut infant stays from an average of 31.6 days before the intervention to 23.7 days afterward, Wexelblatt’s team reported in 2015 in Pediatrics. Duration of opioid treatment dropped as well. By 2016, hospital stays were down to 20 days, he says.
Now, 54 hospitals — almost all delivery hospitals in Ohio — use the weaning protocol, Wexelblatt says. The team has since refined its methods, focusing on family support and nonmedication options for care, like swaddling and breastfeeding. And as of 2013, every delivering mom in the Cincinnati region gets urine-tested for opioids upon admission so that care can start early, if needed. Ohio’s strategy is paying off: Doctors are using fewer opioids to treat NAS babies and the infants are getting out of the hospital faster too, early results suggest.
Researchers at Yale and Dartmouth-Hitchcock have also taken a hard look at the hospitals’ methods, starting with the Finnegan scoring system. Some aspects just didn’t make sense, Holmes and colleagues reported last June in Pediatrics. Nurses sometimes woke sleeping babies or removed them from family members’ arms for scoring, and they gave hungry babies points for crying.
“We said, ‘This is crazy,’ ” Holmes remembers. It makes more sense to just score the babies after they eat and while they’re being held. That way, she says, nurses might be able to sift the actual signs of withdrawal from the normal whines and wails of a hungry or tired baby.
Grossman and colleagues at Yale were skeptical too. Finnegan’s system looks for warning signs like vomiting and fever, but also gives points for sneezing and yawning. The final score guides doctors’ decision to dial meds up or down. “Is it truly best to give morphine to an infant who yawned 4 times instead of 3, as the [scoring system] guides us to do?” they asked in a Hospital Pediatrics commentary in February.
Grossman scoured the scientific literature, searching for clues to improve treatment. But research results bounced all over the place. “We ended up questioning everything,” he says. “It turned out there wasn’t really a good answer for anything we were doing.” Family first Around the same time Grossman was digging into research on opioid withdrawal in newborns, he had his first child, who screamed constantly. “I’m pacing in the middle of the night, thinking, if this was an NAS baby, he’d be on medication immediately.”
Instead, Grossman paced and rocked and held his son — all of the tricks parents use to soothe a cranky newborn. As he found ways to settle the baby, he thought, what if NAS babies needed something similar?
The idea jibed with his experiences at the hospital. Sometimes withdrawing infants would do great for days—their moms were there, and Finnegan scores stayed low. But if moms had to leave, babies would backslide, and scores would rocket up again. “Do these kids need more mom or more meds?” Grossman and colleagues wondered. “We started to think, ‘Well, maybe it’s more mom.’ ”
At Dartmouth-Hitchcock, Holmes and her crew were coming up with their own ideas. The team stopped interpreting Finnegan scores so rigidly, for one. But their biggest change was keeping mothers and babies together, 24-7. It’s called “rooming-in,” and previous studies in Canada and other countries had suggested it might ease babies’ transition from the womb to the world. “What withdrawing babies need is a calm, quiet, dark place where they can be held by a caring individual,” Holmes says. Her team focused on involving moms and families (and even volunteer cuddlers), and the hunch paid off. From 2012 to 2015, the average length of stay for morphine-treated NAS babies dropped from 16.9 days to 12.3 days. The fraction of babies given morphine plummeted too, from 46 percent to 27 percent. Now, two years later, that number has fallen even further — to just 20 percent, she says.
Holmes says her own kids joke about her work: “Babies like their mothers—surprise, surprise! What a discovery!” She laughs, and then adds, “They’re kind of right.”
Grossman’s team at Yale has pushed the family-focused approach even further. “Our mind-set is rooming-in on steroids,” he says. For NAS, parental care is considered more important—and more effective—than medication. Doctors ask parents: “How do we get you here or dad here or grandma here?” Grossman says. “Because that’s what your baby needs.”
His team rolled in other ideas too, like fortifying formula and pumped breast milk with extra calories. And hospital personnel stopped using Finnegan scores to guide medication dosing. Today, they base assessments on three simple parameters: whether an infant can eat, sleep and be consoled.
The patient rooms where parents can bunk with their babies are a world apart from the NICU. One room at Yale has a couch that converts into a bed and ceiling tiles with pictures of Elmo and Tweety Bird. Monitors are muted, nothing beeps incessantly and natural light pours in from the window. There’s plenty of space for parents to walk around and tend to their baby. In these rooms, “it feels like the parent is a necessary part of the care team,” Yale’s Osborn says.
In 2016, babies with NAS stayed in the Yale hospital just 5.9 days — a cliff dive compared with the 2008–2010 average of 22.4 days, Grossman, Osborn and colleagues reported online May 18 in Pediatrics. Even more staggering is the fraction of these babies treated with morphine: just 14 percent in 2016, down from 98 percent in 2008–2010. Taking the plunge From 2008 to 2016, the proportion of opioid-withdrawing infants treated with morphine at Yale New Haven Children’s Hospital dropped from 98 percent to 14 percent, a drastic reduction in the number of babies given the medication.
Click or tap the graph below to learn more.
Yale’s approach basically comes down to common sense, Grossman says: a quiet room, lots of holding, feeding when hungry and simply keeping babies with mom and dad. “It’s not rocket science,” he says. Medication became more of a plan B.
Still, other doctors looking to transform NAS treatment may run into barriers. Not all U.S. hospitals are set up like Dartmouth-Hitchcock or Yale New Haven, Wexelblatt says. There’s not always room for mom to stay with her baby once she’s released. And universal drug testing of moms won’t work everywhere, he warns. In Tennessee, a law passed in 2014 allowed new mothers to be prosecuted for using illegal drugs while pregnant if the newborn was harmed. The law expired last July, but such legislation drives women away from medical care, Wexelblatt says.
It could be that the best care for babies begins with care and compassion for moms. Rather than blame mothers, Holmes says, “We need to do as much as we can to support them in being good parents.”
Fossil DNA may be rewriting the history of elephant evolution.
The first genetic analysis of DNA from fossils of straight-tusked elephants reveals that the extinct animals most closely resembled modern African forest elephants. This suggests that straight-tusked elephants were part of the African, not Asian, elephant lineage, scientists report online June 6 in eLife.
Straight-tusked elephants roamed Europe and Asia until about 30,000 years ago. Much like modern Asian elephants, they sported high foreheads and double-domed skulls. These features convinced scientists for decades that straight-tusked and Asian elephants were sister species, says Adrian Lister, a paleobiologist at the Natural History Museum in London who was not involved in the study. For the new study, researchers extracted and decoded DNA from the bones of four straight-tusked elephants found in Germany. The fossils ranged from around 120,000 to 240,000 years old. The genetic material in most fossils more than 100,000 years old is too decayed to analyze. But the elephant fossils were unearthed in a lake basin and a quarry, where the bones would have been quickly covered with sediment that preserved them, says study author Michael Hofreiter of the University of Potsdam in Germany.
Hofreiter’s team compared the ancient animals’ DNA with the genomes of the three living elephant species — Asian, African savanna and African forest — and found that straight-tusked genetics were most similar to African forest elephants.
When the researchers told elephant experts what they’d found, “Everybody was like, ‘This can’t possibly be true!’” says study coauthor Beth Shapiro of the University of California, Santa Cruz. “Then it gradually became, ‘Oh yeah, I see.… The way we’ve been thinking about this is wrong.’”
If straight-tusked elephants were closely related to African forest elephants, then the African lineage wasn’t confined to Africa — where all elephant species originated — as paleontologists previously thought. It also raises questions about why straight-tusked elephants bore so little resemblance to today’s African elephants, which have low foreheads and single-domed skulls. Accounting for this new finding may not be as simple as moving one branch on the elephant family tree, Lister says. It’s possible that straight-tusked elephants really were a sister species of Asian elephants, but they exhibit genetic similarities to African forest elephants from interbreeding before the straight-tusked species left Africa.
It’s also possible that a common ancestor of Asian, African and straight-tusked elephants had particular genetic traits that were, for some reason, only retained by African and straight-tusked elephants, he says.
Lister and colleagues are now reexamining data on straight-tusked skeletons to reconcile the species’ skeletal features with the new information on their DNA. “I will feel most comfortable if we can understand these genetic relationships in terms of the [physical] differences between all these species,” he says. “Then we’ll have a complete story.”
BOSTON — Some aspects of speech are as Southern as pecan pie. Consider the vowel shift that makes the word pie sound more like “pah.” While that pronunciation is found from Florida to Texas, a new study reveals a surprising diversity in Southern vowel pronunciation that’s linked to a speaker’s age, social class, gender, race and geography.
The research, presented June 29 at a meeting of the Acoustical Society of America, could help software developers create better speech recognition tools for smartphones and other devices. To understand the medley of southern vowel sounds, linguist Margaret Renwick of the University of Georgia in Athens dove into the Digital Archive of Southern Speech. The archive comprises almost 400 hours of interviews with 64 native Southerners representing a mix of ethnicities, social classes, education levels and ages.
Renwick’s analysis of more than 300,000 vowel sounds finds, for example, that Southern upper middle class women are often at the extreme end of variation in pronunciation. While Southern men and women are equally likely to shift the vowel in bet to “bay-ut,” upper middle class Southern women are more likely to stretch the vowel sound in bit to “bee-ut.” They are also most likely to pronounce bait as bite. The finding that women are more inclined to draw a sound out into two syllables — or change it entirely — is in line with other research suggesting that women are linguistic innovators, and less likely to adhere to the norms of standard American English, Renwick said.
For a glue that holds up inside the body, turn to the humble slug, Arion subfuscus. A new super-sticky material mimics slug slime’s ability to stick on slick wet surfaces and could lead to more effective medical adhesives.
The material has two parts: a sticky layer that attaches to a surface, and a shock-absorbing layer that reduces strain. That makes the adhesive less likely to snap off.
Researchers tested the material as a surgical adhesive in a number of different scenarios: It stuck to pig skin and liver. It latched on to a beating pig’s heart, even when the surface was coated in blood. It sealed up a heart defect, preventing liquid from leaking even when the organ was inflated and deflated tens of thousands of times. And it was less toxic in the body than a commonly used commercialized tissue adhesive, researchers report July 28 in Science.
The researchers hope the material could someday be used in surgical procedures in place of invasive sutures and staples.
For the first time in the United States, researchers have used gene editing to repair a mutation in human embryos.
Molecular scissors known as CRISPR/Cas9 corrected a gene defect that can lead to heart failure. The gene editor fixed the mutation in about 72 percent of tested embryos, researchers report August 2 in Nature. That repair rate is much higher than expected. Work with skin cells reprogrammed to mimic embryos had suggested the mutation would be repaired in fewer than 30 percent of cells. In addition, the researchers discovered a technical advance that may limit the production of patchwork embryos that aren’t fully edited. That’s important if CRISPR/Cas9 will ever be used to prevent genetic diseases, says study coauthor Shoukhrat Mitalipov, a reproductive and developmental biologist at Oregon Health & Science University in Portland. If even one cell in an early embryo is unedited, “that’s going to screw up the whole process,” says Mitalipov. He worked with colleagues in Oregon, California, Korea and China to develop the embryo-editing methods.
Researchers in other countries have edited human embryos to learn more about early human development or to answer other basic research questions (SN: 4/15/17, p. 16). But Mitalipov and colleagues explicitly conducted the experiments to improve the safety and efficiency of gene editing for eventual clinical trials, which would involve implanting edited embryos into women’s uteruses to establish pregnancy. In the United States, such clinical trials are effectively banned by a rule that prevents the Food and Drug Administration from reviewing applications for any procedure that would introduce heritable changes in human embryos. Such tinkering with embryo DNA, called germline editing, is controversial because of fears that the technology will be used to create so-called designer babies.
“This paper is not announcing the dawn of the designer baby era,” says R. Alta Charo, a lawyer and bioethicist at the University of Wisconsin Law School in Madison. The researchers have not attempted to add any new genes or change traits, only to correct a disease-causing version of a gene.
In the study, sperm from a man who carries a mutation in the MYBPC3 gene was injected into eggs from women with healthy copies of that gene. Carrying just one mutant copy of the gene causes an inherited heart problem called hypertrophic cardiomyopathy (SN: 9/17/16, p. 8). That condition, which strikes about one in every 500 people worldwide, can cause sudden heart failure. Mutations in the MYBPC3 gene are responsible for about 40 percent of cases. Doctors can treat symptoms of the condition, but there is no cure.
Along with the man’s sperm, researchers injected into the egg the DNA-cutting enzyme Cas9 and a piece of RNA to direct the enzyme to snip the mutant copy of the gene. Another piece of DNA was also injected into the egg. That hunk of DNA was supposed to be a template that the fertilized egg could use to repair the breach made by Cas9. Instead, embryos used the mother’s healthy copy of the gene to repair the cut.
Embryos’ self-healing DNA came as a surprise, because gene editing in other types of cells usually requires an external template, Mitalipov says. The discovery could mean that it will be difficult for researchers to fix mutations in embryos if neither parent has a healthy copy of the gene. But the finding could be good news for those concerned about designer babies, because embryos may reject attempts to add new traits.
Timing the addition of CRISPR/Cas9 is important, the researchers also discovered. In their first experiments, the team added the gene editor a day after fertilizing the eggs. Of 54 injected embryos, 13 were patchwork, or mosaic, embryos with some repaired and some unrepaired cells. Such mosaic embryos probably arise when the fertilized egg copies its DNA before researchers add Cas9, Mitalipov says.
Injecting Cas9 along with the sperm — before an egg had a chance to replicate its DNA — produced only one patchwork embryo. That embryo had repaired the mutation in all its cells, but some cells used the mother’s DNA for repair while others used the template supplied by the researchers.
None of the tested embryos showed any signs that Cas9 was cutting where it shouldn’t be. “Off-target” cutting has been a safety concern with the gene editor because of the possibility of creating new DNA errors.
The study makes progress toward using gene editing to prevent genetic diseases, but there’s still has a long way to go before clinical testing can begin, says Janet Rossant, a developmental biologist at the Hospital for Sick Children and the University of Toronto. “We need to be sure this can be done reproducibly and effectively.”
Famously sneaky particles have been caught behaving in a new way.
For the first time, scientists have detected neutrinos scattering off the nucleus of an atom. The process, predicted more than four decades ago, provides a new way to test fundamental physics. It will also help scientists to better characterize the neutrino, a misfit particle that has a tiny mass and interacts so feebly with matter that it can easily sail through the entire Earth. The detection, reported online August 3 in Science, “has really big implications,” says physicist Janet Conrad of MIT, who was not involved with the research. It fills in a missing piece of the standard model, the theory that explains how particles behave: The model predicts that neutrinos interact with nuclei. And, says Conrad, the discovery “opens up a whole new area of measurements” to further test the standard model’s predictions.
Scientists typically spot neutrinos when they interact with a single proton or neutron. But the new study measures “coherent” scattering, in which a low-energy neutrino interacts with an entire atomic nucleus at once, ricocheting away and causing the nucleus to recoil slightly in response.
“It’s exciting to measure it for the first time,” says physicist Kate Scholberg of Duke University, spokesperson for the collaboration — named COHERENT — that made the new finding.
In the past, neutrino hunters have built enormous detectors to boost their chances of catching a glimpse of the particles — a necessity because the aloof particles interact so rarely. While still rare, coherent neutrino scattering occurs more often than previously detected types of neutrino interactions. That means detectors can be smaller and still catch enough interactions to detect the process. COHERENT’s detector, a crystal of cesium and iodine, weighs only about 15 kilograms. “It’s the first handheld neutrino detector; you can just carry it around,” says physicist Juan Collar of the University of Chicago.
Collar, Scholberg and colleagues installed their detector at the Spallation Neutron Source at Oak Ridge National Laboratory in Tennessee. The facility generates bursts of neutrons and, as a by-product, produces neutrinos at energies that COHERENT’s detector can spot. When a nucleus in the crystal recoils due to a scattering neutrino, a flash of light appears and is captured by a light sensor. The signal of the recoiling nucleus is incredibly subtle — like detecting the motion of a bowling ball when hit by a ping-pong ball — which is why the effect remained undetected until now. The amount of scattering the researchers saw agreed with the standard model. But such tests are still in their early stages, says physicist Leo Stodolsky of the Max Planck Institute for Physics in Munich, who was not involved with the research. “We’re looking forward to more detailed studies to see if it really is accurately in agreement with the expectations.” Physicists hope to find a place where the standard model breaks down, which could reveal new secrets of the universe. More precise tests may reveal discrepancies, he says. “That would be extremely interesting.”
Measuring coherent neutrino scattering could help scientists understand the processes that occur within exploding stars, or supernovas, which emit huge numbers of neutrinos (SN: 02/18/17, p. 24). The process could be used to detect supernovas as well — if a supernova explodes nearby, scientists could spot its neutrinos scattering off nuclei in their detectors.
Similar scattering might also help scientists detect dark matter, an invisible source of mass that pervades the universe. Dark matter particles could scatter off atomic nuclei just as neutrinos do, causing a recoil. The study indicates that such recoils are detectable — good news since several dark matter experiments are currently attempting to measure recoils of nuclei (SN: 11/12/16, p. 14). But it also suggests a looming problem: As dark matter detectors become more sensitive, neutrinos bouncing off the nuclei will swamp any signs of dark matter.
Coherent neutrino scattering detectors could lead to practical applications as well: Small-scale neutrino detectors could eventually detect neutrinos produced in nuclear reactors to monitor for attempts to develop nuclear weapons, for example.
Physicist Daniel Freedman of MIT, who predicted in 1974 that neutrinos would scatter off nuclei, is pleased that his prediction has finally been confirmed. “It’s a thrill.”
I heard it for the first time a few days ago: “She’s copying me!” my 4-year-old wailed in a righteous complaint about her little sister. And she most certainly was copying, repeating the same nonsense word over and over. While it was distressing to my older kid, I thought it was funny that it took her so long to realize her sister copies almost everything she does.
This egregious violation occurred just after I had read about an experiment that pitted young kids against bonobos in a test to see who might copy other individuals more. I’ll get right to the punch line: Kids won, by a long shot. The results, published online July 24 in Child Development, show that despite imitation annoying older siblings everywhere, it’s actually really important.
“Imitation is one of the most essential skills for being human,” says study coauthor Zanna Clay, a comparative psychologist at the University of Birmingham and Durham University, both in England. Learning how to talk, operating the latest iPhone and figuring out how to buy bulk goods at the local co-op — these skills all rely on imitation. Not only that, but imitation is also important for cementing social relationships. My daughter notwithstanding, “Humans like to be imitated, and we like those who imitate us,” Clay says. Clay and her colleague Claudio Tennie tested just how strong the urge to imitate is in 77 children ages 3 to 5 and a group of 46 bonobos ages 3 to 29. In one-on-one trials, the researchers sat next to the kids and bonobos with a small wooden box about the size of a hand. Inside was a treat: a sticker for the kids and a bit of apple for the bonobos.
Before opening the box, the researcher performed nonsensical actions over it, either rubbing the box with the back of the hand and doing a wrist twist in the air or tracing a cross into the top of the box and then tracing the edges.
These hand motions were totally irrelevant to the actual opening of the box. Nonetheless, after seeing the gestures, the vast majority of the kids made the same motions before trying to open their own box. Not a single bonobo, though, copied the irrelevant actions. What the bonobos did — not copying the meaningless gestures — “is the rational thing to do,” says Clay. “Yet the irrational thing that the kids did is part of the reason why human cultures have evolved so rapidly and so diversely.”
Such excessive imitation, called overimitation, is a special form of copying in which people perform actions that clearly serve no purpose. It may be behind rituals, social norms and language that keep our societies running smoothly.
And it may be unique to humans: Other studies have failed to spot overimitation among chimpanzees and orangutans. These findings hint that our powerful urge to imitate even nonsensical gestures may be one of the things that separate humans from other apes.
The 2011 tsunami that devastated Japan’s coast cast an enormous amount of debris out to sea — way out. Japanese marine life took advantage of the new floating real estate and booked a one-way trip to America. From 2012 to 2017, at least 289 living Japanese marine species washed up on the shores of North America and Hawaii, hitching rides on fishing boats, docks, buoys, crates and other nonbiodegradable objects, a team of U.S. researchers report in the Sept. 29 Science.
Organisms that surprisingly survived the harsh 7,000-kilometer journey across the Pacific Ocean on 634 items of tsunami debris ranged from 52-centimeter-long fish (a Western Pacific yellowtail amberjack) to microscopic single-celled protists. About 65 percent of the species have never been seen in North America’s Pacific waters. If these newcomers become established, they have the potential to become invasive, disrupting native marine habitats, says study coauthor James Carlton, a marine scientist at Williams College in Mystic, Conn. Meet some of the slimiest, strangest and potentially most invasive marine castaways that took this incredible journey:
The Northern Pacific sea star (Asterias amurensis) is among the world’s most invasive species. Though this purple and yellow sea star is normally found in shallow habitats, it can live as deep as 200 meters.
Skeleton shrimp (Caprella cristibrachium and C. mutica (shown)) grasp onto algae with their strong rear claws, earning them the nickname “praying mantis of the sea.” These lanky amphipods can grow up to about 5 centimeters long and are found in the Sea of Japan. A white, brittle Bryozoan (Biflustra grandicella) that can grow as big as a basketball is already invasive in Australia. The tiny swimming larvae of these sea creatures, also known as moss animals, may live up to a week, long enough to settle in to a new habitat.
Most of the wooden Japanese debris items collected carried at least one of seven species of large wormlike mollusks called Japanese shipworms (Psiloteredo sp.). Some of the more monstrous shipworms found, which bore into everything from wooden pilings to docks, had grown to about 50 centimeters long. Five Japanese barred knifejaw fish (Oplegnathus fasciatus), also known as striped beakfish, were found trapped in the stern well of a Japanese fishing boat found beached in 2013 in Washington. These black-and-white striped fish are native to the Northwest Pacific Ocean and Hawaii. The well acted as a tide pool of sorts, sustaining the fish during their two-year journey.
The wavy-shelled slipper snail (Crepidula onyx), also known as a slipper limpet, has essentially come full circle in its journey around the Pacific Ocean. Native to the U.S. West Coast, the well-traveled snail became an invasive species in Japan, and now has returned to America on Japanese debris.
A growing band of digital characters that converse, read faces and track body language is helping humans to communicate better with one another. While virtual helpers that perform practical tasks, such as dealing with customer service issues, are becoming ubiquitous, computer scientist M. Ehsan Hoque is at the forefront of a more emotionally savvy movement. He and his team at the University of Rochester in New York create software for digital agents that recognize when a person is succeeding or failing in specific types of social interactions. Data from face-to-face conversations and feedback from professional counselors and interviewers with relevant expertise inform this breed of computer advisers.
One of Hoque’s digital helpers grooms people to be better public speakers. With words on a screen, this attentive app notes, for example, how many times in a practice talk a person says “um,” gestures inappropriately or awkwardly shifts vocal tone. With the help of Google Glass, the app even offers useful reminders during actual speeches. Another computerized helper, this one in the form of an avatar, helps people hone their job interviewing skills, flagging long-winded responses or inconsistent eye contact in practice interviews. In the works are computerized conversation coaches that can improve speech and communication skills among people with developmental conditions such as autism and mediate business meetings in ways that encourage everyone to participate in decision making.
“There has been some progress in artificial intelligence, but not much in developing emotional aspects of AI,” Hoque says. “We’re just cracking through the surface at this point.” The U.S. Department of Defense and the U.S. Army have taken notice. With their financial support, Hoque is developing avatars that collaborate with humans to solve complex problems, and digital observers that monitor body language to detect when people are lying. This is heady stuff for a 35-year-old who earned a doctoral degree just four years ago. Hoque, who was born in Bangladesh and immigrated to the United States as a teenager, did his graduate work with the MIT Media Lab’s Affective Computing research group. The group’s director, Rosalind Picard, helped launch the field of “affective computing” in the 1990s, which focuses on the study and development of computers and robots that recognize, interpret and simulate human emotions.
Hoque’s approach puts a service spin on affective computing. As a grad student, he developed software he dubbed MACH, short for My Automated Conversation coacH. This system simulates face-to-face conversations with a computer-generated, 3-D man or woman that sees, hears and makes decisions while conversing with a real-life partner. Digital analyses of a human partner’s speech and nonverbal behavior inform the avatar’s responses during a session. A simulated coach may, for instance, let a user know if smiles during an interview look forced or are mistimed. After a session, users see a video of the interaction accompanied by displays of how well or poorly they did on various interaction skills, such as keeping eye contact and nodding at appropriate times.
MACH got its start in trials that trained MIT undergraduates how to conduct themselves during interviews with career counselors. First, Hoque analyzed smiles and other behaviors that either helped or hurt the impressions job candidates left on experienced counselors in mock interviews. In a series of follow-up studies, his team developed an automated system that recognized impression-enhancing behaviors during simulated interviews. That pilot version of MACH was then put to the test. Women, but not men, who received MACH training and got feedback from their digital coach while watching videos of their initial interviews with a counselor displayed substantial improvement in follow-up interviews. MACH trainees who watched interview videos but got no feedback showed minimal improvement. Testing with larger groups of men and women is under way. As he developed MACH, Hoque consulted MIT sociologist and clinical psychologist Sherry Turkle. That was a bold move, since Turkle has warned for 30 years that, despite its pluses, digital culture discourages person-to-person connections. Social robots, in particular, represent a way for people to escape the challenges of forging authentic relationships, Turkle contends.
But she came away impressed with Hoque, whose goals she calls refreshingly modest and transparent. “His avatars will be helpers and facilitators,” she says, “not companions, friends, therapists and pretend people.”
Hoque’s approach grew out of personal experience. He is the primary caregiver for his 16-year-old brother, Eshteher, who has Down syndrome and does not speak. Eshteher can make sounds to refer to certain things, such as food, and has limited use of sign language. “I’ve spent a lot of time with him and can read what he’s experiencing, like when he’s frustrated or repentant,” Hoque says. So it’s not surprising that Hoque’s next-generation MACH, dubbed LISSA for Live Interactive Social Skill Assistance, is an avatar that conducts flexible, “getting acquainted” conversations while providing feedback on users’ eye contact, speaking volume, smiling and body movements via flashing icons.
LISSA has shown promise in preliminary tests aimed at improving the conversational chops of college students attending speed-dating sessions and individuals with autism spectrum disorders. Hoque plans to expand this technology for use with people suffering from social phobia and post-traumatic stress disorder. He’s also working on an avatar that trains doctors to communicate clearly and compassionately with patients being treated for life-threatening cancers.
Hoque’s work on emotionally perceptive avatars may eventually transform the young industry of digital assistants, currently limited to voices-in-a-box such as Apple’s Siri and Microsoft’s Cortana, says cognitive scientist Mary Czerwinski, a principal researcher at Microsoft Research Lab in Redmond, Wash. Avatar research “could lead to more natural, personable digital assistants,” Czerwinski predicts. Hoque agrees.
“In the future, we’ll all have digital, personalized assistants,” he says. If he gets his way, emotionally attuned helpers will make us more social and less isolated. That’s something to applaud — if we can manage to put down our smartphones.