Tag: biology

A short dose of ultraviolet light might save North America’s bats

8:24 am

Researchers have found that the fungus that has been decimating bat populations in the eastern United States for the past decade is easily killed by a short dose of ultraviolet light.

Upon being compared to six non-pathogenic Pseudogymnoascus species, it was found that P. destructans lacks a key enzyme that allows it to repair DNA damage caused by ultraviolet light. When samples of the fungus were exposed to a low dose of UV-C light from a handheld source, the survival rate was only about 15 percent – this dropped to less than 1 percent when the dose was moderate. In both cases, the duration of exposure was a matter of no more than a few seconds.

Next comes a control group experiment. If this proves true, than it might be possible to safely sterilize both bat populations and caves of the fungus. To work, however, the task will likely require repeated yearly visits to bat hibernation sites to kill the fungus before it causes the bats to wake up in the winter. Such visits have their own problems, and would be difficult to pay for. However, I am sure the caving community across the U.S. would be glad to volunteer for this effort, and could handle it.

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Worms on Mars!

9:09 am

Scientists growing plants on Earth using a simulated Martian soil have found that earthworms like it.

These slimy invertebrates play a key role in making Earth soil healthy by digesting dead organic matter and excreting a potent fertilizer that helps release nutrients like nitrogen and phosphorus. Their constant burrowing also helps lighten up the soil, allowing air and water to seep through better.

That’s an important improvement for the simulated Mars soil, which water struggled to soak through in previous tests. Altogether, the tests showed that the combination of worms and pig slurry helped the plants grow in Martin soil, and the worms not only thrived but reproduced. “Clearly the manure stimulated growth, especially in the Mars soil simulant, and we saw that the worms were active,” says Wamelink. “However, the best surprise came at the end of the experiment when we found two young worms in the Mars soil simulant.”

Obviously, we do not know yet how the worms would respond to the lower Martian gravity, but it sure would be a significant experiment to see them reproduce there.

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Russia astronauts have found bacteria living on the outside of ISS

8:42 am

Russia astronauts have found bacteria that was not intentionally brought into space living on the outside of ISS.

They are being studied on Earth but most likely they don’t pose any sort of danger, Russian cosmonaut Anton Shkaplerov told TASS on Monday. According to him, during spacewalks from the International Space Station under the Russian program, the cosmonauts took samples with cotton swabs from the station’s external surface. In particular, they took probes from places where the accumulation of fuel wastes were discharged during the engines’ operation or at places where the station’s surface is more obscure. After that, the samples were sent back to Earth.

“And now it turns out that somehow these swabs reveal bacteria that were absent during the launch of the ISS module. That is, they have come from outer space and settled along the external surface.”

I suspect it is a bit of hyperbole to say the bacteria came from outer space. It more likely came from either the station itself, or later spacecraft docking with the station. At the same time, the article is vague about what has been discovered. For example, it says nothing about the bacteria itself.

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A simple and inexpensive skin cancer detector wins award

10:10 am

A simple and inexpensive skin cancer detector has won the $40,000 2017 James Dyson award.

Designed by a team from McMaster University in Canada, the sKan can make more accurate diagnoses quickly and reasonably cheaply. It’s based around the fact that cancer cells have a faster metabolic rate than healthy cells, meaning they release more heat. To check if a patch of skin has the beginnings of a melanoma, the suspected area is first cooled with an ice pack before the sKan device is placed against the skin.

Using an array of temperature sensors called thermistors, the sKan will then monitor the area as the skin warms back up. If there’s a melanoma present, it will warm up faster than the surrounding skin, revealing itself on a heat map and temperature difference time plot created through a connected computer program.

Once this device is in the hands of dermatologists, they will be able to very quickly diagnose whether a skin mole or freckle is dangerous or not.

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NASA forces retraction of astronaut vision study due to privacy issues

9:01 pm

NASA has forced the retraction of an important science paper researching the damage to vision for astronauts on long spaceflights because of a concern the privacy of the astronauts might be violated.

According to the first author, the paper included information that could identify some of the astronauts that took part in the study — namely, their flight information. Although the author said he removed the identifying information after the paper was online, NASA still opted to retract it. But a spokesperson at NASA told us the agency did not supply the language for the retraction notice. The journal editor confirmed the paper was retracted for “research subject confidentiality issues,” but referred a question about who supplied the language of the notice back to NASA.

…According to first author Noam Alperin of the University of Miami Miller School of Medicine in Florida, the paper “Role of Cerebral Spinal Fluid in Space Flight Induced Ocular Changes and Visual Impairment in Astronauts” showed that visual damage caused by long space flights resulted from tiny shifts in the volume of spinal fluid — not vascular changes, as many experts had previously thought.

Protecting the health privacy of the astronauts is something NASA and the doctors that work with them are legally required to do. However, in this case the paper had been scrubbed of this information a long time ago. To force its retraction now when the actual. research was valid and important and the privacy of the astronauts was now protected seems an over reaction to me. Then again, NASA might be under legal pressure from the astronauts themselves, and thus forced to act.

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Tupperware in space!

9:20 am

Capitalism in space: Tupperware and NASA have partnered to provide space-grown gardens an artificial material for roots to grow and be watered.

First flown to the ISS in 2014, the Vegetable Production System, (aka the “Veggie” facility), is an experiment for growing plants in zero gravity in a plastic greenhouse. It consists of a collapsible plastic tent with a controllable atmosphere lit by red, blue, and green LED lamps to promote growth. Since dirt and space travel don’t mix, the seeds are embedded in rooting “pillows” that take the place of soil to retain water and give the roots somewhere to grow.

The problem is that the pillows don’t hold onto water very well, so the hydroponic system keeps drying out unless it’s tended regularly. Given how much it costs to keep an astronaut on the station, time spent watering the lettuce is about as economical as hiring a brain surgeon to mow the lawn, so a team led by Howard Levine at the Kennedy Space Center is working on some upgrades for the system.

One key example is the semi-hydroponic Passive Orbital Nutrient Delivery System (PONDS) being produced by Tupperware. With over 75 years of experience working with food-grade plastics as well as injection molding and other plastic manufacturing processes, Tupperware is producing a new disposable pillow made of plastic mesh that uses capillary forces and unusual geometries to replace gravity and hold water in like a zero gravity sponge while permitting root formation.

In other words, rather than design and built the pillows itself, as it would have in the past, NASA has hired Tupperware to build them. I am willing to bet this is saving NASA both time and money.

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Growing cucumbers in space

9:48 am

New research growing cucumbers on ISS has found that the roots of these plants grew in the direction of water in weightlessness.

Plant roots grow to find water, according to a process known as hydrotropism. Roots are also influenced by gravity and tend to grow downwards, called gravitropism. To find out whether gravity or water had the greater influence on root growth, investigators grew cucumber plants in the microgravity environment on board the International Space Station. In their experiments, water (or hydrotropism) had more influence in controlling root growth.

“We will be able to utilize roots’ ability to sense moisture gradients for controlling root growth orientation and efficiently growing plants in future space farms,” said Dr. Hideyuki Takahashi, senior author of the New Phytologist study.

You can read the full science paper here.

This might sound obvious, but it isn’t. Past plant growth experiments on Mir and ISS had tended to show that plant roots did not know where to grow in weightlessness, suggesting that they needed gravity to guide the roots to water. Because of this, later experiments in space provided the roots complicated engineering to guide the roots to the water.

This experiment shows that maybe that complex engineering is not necessary, or at least could be simplified a bit. At a minimum it is crucial information engineers will need to design any future gardens for interplanetary spaceships with long term weightlessness.

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How cats used humans to conquer the world

8:42 am

Link here. The bottom line is this:

Compared to many other animals, cats have also changed very little in the domestication process. Behaviorally, they’ve become more tolerant of humans. Physically, though, they’re still about the same size and shape. They still like to pounce on small prey. “Cats have done since before they were domesticated what we needed them to do,” says Leslie Lyons, a feline geneticist at the University of Missouri. In other words, unlike dogs that herd sheep or hunt badgers, cats didn’t need humans to breed them to become good mouse hunters.

In other words, cats did what they want (as they always do), and humans paid them with food and companionship, while providing them the transportation they needed to reach every continent.

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Worm grows 2 heads on ISS

5:29 pm

The uncertainty of science: For reasons that are not yet understood, a flatworm fragment flown to ISS in a microgravity experiment regenerated with two heads.

But the most dramatic difference was a type of regeneration observed in one of the 15 worm fragments sent to the ISS. That worm returned to the scientists with two heads (one on each end of its body), a type of regeneration so rare as to be practically unheard of — “normal flatworms in water never do this,” Levin told Live Science. When the researchers snipped both heads off back on Earth, the middle portion regenerated into a two-headed worm again.

“And these differences persist well over a year after return to Earth!” Levin said. “Those could have been caused by loss of the geomagnetic field, loss of gravity, and the stress of takeoff and landing — all components of any space-travel experience for living systems going to space in the future,” he said.

The flatworms that flew in space showed other significant differences from the control group that stayed on Earth, further suggesting that for flatworms at least the environment of weightlessness causes more problems that were expected.

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How NIMH policy effects research

8:24 am

The uncertainty of science: A policy change in how the National Institute of Mental Health (NIMH) awards grants during the Obama administration has had a profound influence on the research of mental-health in the United States.

An analysis by Nature suggests that the number of clinical trials funded by the NIMH dropped by 45% between 2009 and 2015. This coincides with the agency’s launch, in 2011, of the Research Domain Criteria (RDoC) — a framework for research on the mechanisms of mental illness. The NIMH’s roll-out of RDoC included asking researchers to focus more on the biological bases of behaviour — such as brain circuitry and genetics — than on the broader symptoms that clinicians typically use to define and classify mental illness.

The NIMH’s embrace of fundamental research has infuriated many clinical researchers, who see it as an attempt to invalidate their methods — and say that there is scant evidence to support the idea that using RDoC will lead to greater insight or better treatments for mental illness. Many of these researchers also note that NIMH funding for clinical trials has declined steadily over the past decade, adding to the perception that the agency now favours research that uses the RDoC framework.

Read the article. I have no idea if the change in NIMH policy is a good or bad thing. What disturbs me however is the federal government’s overall top-down control over mental-health research. Rather than obtain funding from many different sources — which would allow for the greatest flexibility and the most creativity — this research field appears to depend almost entirely on NIMH grants. Thus, the particular preferences of that agency dictates the nature of the research, whether or not its preferences are right.

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Rat sperm exposed to weightlessness still produces healthy rats

8:46 am

An experiment that flew on ISS has found that rat sperm exposed to weightlessness and space radiation and then used on Earth to fertilize eggs still produce healthy rats.

The first issue for the researchers was how best to get the sperm up there. They decided to have the samples freeze-dried, just like instant coffee. This meant the sperm weighed almost nothing and could be kept at room temperature, ideal for travel on a rocket, or on a distant planet. The mouse sperm then spent 288 days on the ISS before coming back to Earth to be compared with fresh sperm from the same mice.

First, the scientists analysed how space travel affected the integrity of the DNA within the sperm. We know that high levels of fragmentation of sperm DNA are associated with male infertility. As expected, the scientists discovered that the space sperm had higher amounts of fragmented DNA than the sperm which had stayed on Earth. However, when used to fertilise a mouse egg, the space sperm resulted in a similar number of healthy embryos being generated – and these offspring had the ability to develop into normal, fertile adult mice. A final test the researchers did was to compare the patterns of genes being expressed within the brains of the adult mice. Here, the researchers saw no overall differences and concluded the space sperm was equally capable of generating offspring.

Obviously, this result is encouraging, but we are still a long way from nonchalantly letting women get pregnant and give birth in space. The risks on the child remain too great and are unknown.

In fact, I suspect the first time a child is born and raised in space will be an event that is unplanned.

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Irreplaceable plant specimens destroyed by Australian customs.

10:29 am

Do the paperwork! Because the proper paperwork was not completed, and then mailed to the wrong address, Australian customs officials destroyed six daisy specimens, some collected in the 1700s.

Earlier this week, many botanists learned about the destruction of six type specimens of daisies—some collected during a French expedition to Australia from 1791 to 1793—which the National Museum of Natural History (NMNH) in Paris had mailed along with 99 other specimens to the Queensland Herbarium in Brisbane, Australia.

After the package arrived in Brisbane in early January, the specimens were held up at customs because the paperwork was incomplete. Biosecurity officers asked the Queensland Herbarium for a list of the specimens and how they were preserved, but the herbarium sent its responses to the wrong email address, delaying the response by many weeks. In March, the officers requested clarification, but then incinerated the samples. “It’s like taking a painting from the Louvre and burning it,” says James Solomon, herbarium curator at the Missouri Botanical Garden in St. Louis.

According to Australia’s Department of Agriculture and Water Resources, which enforces biosecurity rules, part of the problem was that the samples had a declared value of $2—and its agents routinely destroy low-value items that have been kept longer than 30 days. Michel Guiraud, director of collections at NMNH, says his museum’s policy is to put minimal values on shipments. “If it is irreplaceable, there is no way to put an insurance value on it,” he says.

It appears that the fault here is not entirely limited to Australian customs. Both the Paris and Brisbane museums appear to have been very sloppy in this matter.

The result, for now, is that some research organizations are now ceasing all shipments to Australia.

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