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No, that’s not the sun. It’s Jupiter, ablaze with infrared light in new images taken in preparation for the Juno spacecraft’s July 4 arrival at the king of the planets. This image shows how heat welling up from deep within the planet gets absorbed by gas in the atmosphere, which can tell researchers how stuff moves around beneath Jupiter’s thick blanket of clouds. Juno won’t look for infrared light, but it will (among other things) measure how much microwave radiation is being blocked by water lurking within Jupiter’s atmosphere.

The map is pieced together from multiple images obtained at the Very Large Telescope in Chile over the past several months. Ground-based images such as these will help researchers understand what Juno is peering at each time it swoops in close to Jupiter’s clouds over the next 20 months.

For women thinking about fertility treatments, there may be one less thing to worry about.

A long-term study shows that women who underwent in vitro fertilization are not significantly more likely to develop breast cancer than women in the general public or women who opted for other fertility treatments. The results are reported July 19 in JAMA.

The fertility treatment alters progesterone and estradiol levels in women trying to get pregnant. Yo-yoing hormones have been linked to an increase in a woman’s odds of developing breast cancer, but studies are divided on whether IVF itself actually ups cancer risk.

Alexandra van den Belt-Dusebout of the Netherlands Cancer Institute in Amsterdam and her colleagues tracked 19,158 women who underwent in vitro fertilization treatment between 1983 and 1995 and 5,950 women who underwent other fertility treatments between 1980 and 1995.

Following up two decades later, the team found that 948 of the women had developed breast cancer. But breast cancer rates didn’t differ much between groups: 163.5 per 100,000 women for those who had IVF compared to 167.2 women on other fertility treatments and 163.3 women in the general public.

These orderly patterns of dark blue dots indicate where individual chlorine atoms are missing from an otherwise regular grid of atoms. Scientists manipulated these vacancies to create a supersmall data storage device.

The locations of vacancies encode bits of information in the device, which Sander Otte of Delft University of Technology in the Netherlands and colleagues describe July 18 in Nature Nanotechnology. The team arranged and imaged the vacancies using a scanning tunneling microscope. The storage system, which can hold a kilobyte of data, must be cooled to a chilly −196° Celsius to work.
To demonstrate the technique, the researchers transcribed an excerpt from a famous 1959 lecture by physicist Richard Feynman, “There’s Plenty of Room at the Bottom,” which predicted the importance of nanotechnology. In each block, paired rows represent letters. Blocks marked with an “X” were unusable. The encoded 159 words of text fill a region a ten-thousandth of a millimeter wide.

If scaled up, the researchers say, the technology could store the full contents of the U.S. Library of Congress in a cube a tenth of a millimeter on each side.

NEW ORLEANS — Popular heartburn drugs — already under investigation for possible links to dementia, kidney and heart problems (SN: 6/11/16, p. 8) — have a new health concern to add to the list. An analysis of almost 250,000 medical records in Denmark has found an association with stroke.

Researchers from the Danish Heart Foundation in Copenhagen studied patients undergoing gastric endoscopy from 1997 to 2012. About 9,500 of all patients studied suffered from ischemic strokes, which occur when a blood clot blocks a blood vessel in the brain.

Overall, the risk of stroke was 21 percent higher in patients taking a proton pump inhibitor, a drug that relieves heartburn, the researchers reported November 15 during the American Heart Association’s annual meeting. While those patients also tended to be older and sicker to start with, the level of risk was associated with dose, the researchers found. People taking the lowest drug doses (between 10 and 20 milligrams a day, depending on the drug) did not have a higher risk. At the highest doses, though, Prevacid (more than 60 mg/day) carried a 30 percent higher risk and Protonix (more than 80 mg/day) a 94 percent higher risk. For Prilosec and Nexium, stroke risk fell within that range.

Introduced in the 1980s, proton pump inhibitors are available in both prescription and over-the-counter forms. While they are valuable drugs, “their use has been increasing rapidly,” says lead author Thomas Sehested, adding that people often take them for too long, or without a clear reason. Before taking them, he says, “patients need a conversation with their doctor to see if they really need these drugs.”

These skeletons are spilling their guts about the size of the body cavity that housed these animals’ stomach and intestines.

Using digital 3-D scans of mounted skeletons, researchers estimated the body cavity volume in 126 species. Of the 76 mammal species, plant eaters had bigger bellies; their relative torso volumes were about 1.5 times as large as those of carnivores, researchers report online November 4 in the Journal of Anatomy.

The study is the first to quantitatively test the long-held idea that herbivores have bigger torsos, says Marcus Clauss of the University of Zurich. Plant eaters are thought to need extra space for complex systems that digest a leafy diet.
Surprisingly, Clauss and colleagues didn’t find the same pattern in nonavian dinosaurs, birds or reptiles, but the researchers had fewer skeletons to compare. Of the 27 dinosaurs, for example, only four were carnivores.

Still, the research suggests that in tetrapods — four-limbed vertebrates — only mammalian herbivores have larger body cavities, raising questions about why that might be evolutionarily. “Everybody goes crazy about the long neck or the strange things” on an animal’s head, Clauss says. But few scientists have focused on the torso’s frame and how diet helps sculpt it over time. “This study emphasizes that the torso is an important part of overall body shape.”

A new blood test can detect even tiny amounts of infectious proteins called prions, two new studies show.

Incurable prion diseases, such as mad cow disease (BSE) in cattle and variant Creutzfeldt-Jakob disease (vCJD) in people, result from a normal brain protein called PrP twisting into a disease-causing “prion” shape that kills nerve cells in the brain. As many as 30,000 people in the United Kingdom may be carriers of prions that cause vCJD, presumably picked up by eating BSE-tainted beef. Health officials worry infected people could unwittingly pass prions to others through blood transfusions. Four such cases have already been recorded. But until now, there has been no way to screen blood for the infectious proteins.
In the test, described December 21 in Science Translational Medicine, magnetic nanobeads coated with plasminogen — a protein that prions grab onto — trap prions. Washing the beads gets rid of the rest of the substances in the blood. Researchers then add normal PrP to the beads. If any prions are stuck to the beads, the infectious proteins will convert PrP to the prion form, which will also stick to the beads. After many rounds, the researchers could amplify the signal enough to detect vCJD prions in all the people in the studies known to have the disease.

No healthy people or people with other degenerative brain diseases (including Alzheimer’s and Parkinson’s) in either study had evidence of the infectious proteins in their blood. And only one of 83 people with a sporadic form of Creutzfeld-Jakob disease tested positive. Those results indicate that the test is specific to the vCJD prion form, so a different test is needed to detect the sporadic disease.

In two cases, researchers detected prions in frozen blood samples collected 31 months and 16 months before people developed vCJD symptoms.

Chalk up one more loss for physicists searching for dark matter. Scientists with the XENON100 experiment have largely ruled out another experiment’s controversial claim of detecting dark matter.

XENON100, located in Italy’s Gran Sasso National Laboratory, aims to directly detect particles of dark matter — the unknown substance that scientists believe makes up the bulk of matter in the cosmos (SN: 11/12/16, p. 14).

In their new analysis, published online January 3 at arXiv.org, XENON100 scientists looked for an annual variation in the rate of blips in their detector, a tank filled with 161 kilograms of liquid xenon. Such a signal could be a hallmark of Earth’s motion through a prevailing wind of dark matter particles as the planet makes its yearly jaunt around the sun. Another dark matter experiment at Gran Sasso, DAMA/LIBRA, claims to have found strong evidence of a yearly modulation, but other experiments have failed to replicate the result.
Scientists combed over four years of data for events that could be caused by dark matter interacting with electrons in XENON100. The researchers found no evidence of an annual cycle, contradicting DAMA’s claim.

Dark matter optimists can still cling to a caveat, though: DAMA uses a different detection material, composed of sodium iodide crystals rather than xenon. That might explain the difference between the two experiments. Future experiments will attempt to replicate DAMA’s result using the same material.

River piracy
RIV-er PAHY-ruh-see n.
The diversion of headwaters from one stream into another

Ahoy! There be liquid booty on the move in the high mountains. Since May 2016, a channel carved through one of northwestern Canada’s largest glaciers has allowed one river to pillage water from another, new observations reveal. This phenomenon, almost certainly the result of climate change, is the first modern record of river piracy caused by a melting glacier, researchers report online April 17 in Nature Geoscience. Such piracy was rampant as the colossal ice sheets of the Last Glacial Maximum began shrinking around 18,000 years ago.
For hundreds of years, the Kaskawulsh Glacier formed a wall that segregates snow and ice meltwater into two streams: the Slims River, which joins with other streams and crosses Alaska before draining into the Bering Sea, and the Kaskawulsh River, which flows southward into the Pacific Ocean.

Last summer, geomorphologist Daniel Shugar of the University of Washington Tacoma and colleagues discovered that melting had carved a canyon across the toe of Kaskawulsh Glacier. This new channel diverts almost all meltwater into the Kaskawulsh River. That’s robbed the now largely parched Slims River and could decrease fish populations and the availability of nutrients downstream, the researchers predict.

Newly named fossils suggest that a weird and varied chapter in amphibian deep history isn’t totally over.

Small fossils about 220 million years old found along steep red slopes in Colorado represent a near-relative of modern animals called caecilians, says vertebrate paleontologist Adam Huttenlocker of the University of Southern California in Los Angeles.

Caecilians today have long wormy bodies with either shrunken legs or none at all. Yet the nearly 200 modern species of these toothy, burrow-dwelling tropical oddballs are genuine amphibians. The fossil creatures, newly named Chinlestegophis jenkinsi, still had legs but could be the oldest known near-relatives of caecilians, Huttenlocker and colleagues suggest.

A popular view of the amphibian family tree has put caecilians on their own long, peculiar branch beside the ancient frogs and salamanders. But a close look at the new fossils suggests a much earlier split from ancestral frogs and salamanders, the researchers propose June 19 in Proceedings of the National Academy of Sciences. The move puts the caecilians into “a strange but incredibly diverse” group, the stereospondyls, Huttenlocker says. These species included elongated, short-legged beasts with heads shaped like toilet lids.

Among the many stereospondyls, Huttenlocker speculates that caecilians came from “an aberrant branch of miniaturized forms that went subterranean.” And today’s legless burrowers could be this once-flourishing group’s sole survivors.

Brains are like sponges, slurping up new information. But sponges may also be a little bit like brains.

Sponges, which are humans’ very distant evolutionary relatives, don’t have nervous systems. But a detailed analysis of sponge cells turns up what might just be an echo of our own brains: cells called neuroids that crawl around the animal’s digestive chambers and send out messages, researchers report in the Nov. 5 Science.

The finding not only gives clues about the early evolution of more complicated nervous systems, but also raises many questions, says evolutionary biologist Thibaut Brunet of the Pasteur Institute in Paris, who wasn’t involved in the study. “This is just the beginning,” he says. “There’s a lot more to explore.”

The cells were lurking in Spongilla lacustris, a freshwater sponge that grows in lakes in the Northern Hemisphere. “We jokingly call it the Godzilla of sponges” because of the rhyme with Spongilla, say Jacob Musser, an evolutionary biologist in Detlev Arendt’s group at the European Molecular Biology Laboratory in Heidelberg, Germany.

Simple as they are, these sponges have a surprising amount of complexity, says Musser, who helped pry the sponges off a metal ferry dock using paint scrapers. “They’re such fascinating creatures.”
With sponges procured, Arendt, Musser and colleagues looked for genes active in individual sponge cells, ultimately arriving at a list of 18 distinct kinds of cells, some known and some unknown. Some of these cells used genes that are essential to more evolutionarily sophisticated nerve cells in other organisms for sending or receiving messages in the form of small blobs of cellular material called vesicles.

One such cell, called a neuroid, caught the scientists’ attention. After seeing that this cell was using those genes involved in nerve cell signaling, the researchers took a closer look. A view through a confocal microscope turned up an unexpected locale for the cells, Musser says. “We realized, ‘My God, they’re in the digestive chambers.’”

Large, circular digestive structures called choanocyte chambers help move water and nutrients through sponges’ canals, in part by the beating of hairlike cilia appendages (SN: 3/9/15). Neuroids were hovering around some of these cilia, the researchers found, and some of the cilia near neuroids were bent at angles that suggested that they were no longer moving.
The team suspects that these neuroids were sending signals to the cells charged with keeping the sponge fed, perhaps using vesicles to stop the movement of usually undulating cilia. If so, that would be a sophisticated level of control for an animal without a nervous system.

The finding suggests that sponges are using bits and bobs of communications systems that ultimately came together to work as brains of other animals. Understanding the details might provide clues to how nervous systems evolved. “What did animals have, before they had a nervous system?” Musser asks. “There aren’t many organisms that can tell us that. Sponges are one of them.”