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Astronauts Can Suffer a Decade of Bone Loss During Months in Space, New Research Suggests – Gizmodo

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The new research found that human bones, like the wrist bone pictured here, suffers from accelerated loss of density as the result of long-duration missions in space.
Image: L. Gabel et al., 2022

Long-term exposure to microgravity results in the loss of bone density, and new research reveals the disturbing extent to which this happens and finds that astronauts may never fully recover.

“The detrimental effect of spaceflight on skeletal tissue can be profound,” reads the opening sentence of new research published today in Scientific Reports. Profound is right. The study, led by kinesiologists Leigh Gabel and Steven Boyd from the University of Calgary, found that astronauts who participate in long-duration spaceflights (i.e. missions longer than three months) exhibit signs of incomplete bone recovery even after a full year back on Earth. Long-duration missions, it would seem, result in the premature aging of the bones, particularly bones in the weight-bearing lower extremities.

“We found that weight-bearing bones only partially recovered in most astronauts one year after spaceflight,” Gabel said in a statement. “This suggests the permanent bone loss due to spaceflight is about the same as a decade worth of age-related bone loss on Earth.”

The good news, if there is any in all of this, is that space-based resistance training can serve to limit the amount of bone loss and speed recovery. Previous research by the same team showed that “astronauts were more likely to preserve their bone density and strength if they increased in-flight lower body resistance training volume relative to preflight,” as the scientists write.

The new research shows how dependent we are on gravity for maintaining our bone strength. Each day is a constant struggle against gravity, but all this work does our body good, as it continually strengthens our bones. In space, however, astronauts just float around with barely any physical resistance, resulting in the gradual loss of bone density.

“Bone loss happens in humans—as we age, get injured, or any scenario where we can’t move the body, we lose bone,” Gabel said. “Understanding what happens to astronauts and how they recover is incredibly rare. It lets us look at the processes happening in the body in such a short time frame.”

The team traveled to NASA’s Johnson Space Center in Houston, Texas, to perform the study. In total, 17 international astronauts (14 men and three women) were studied, all of whom performed long-duration missions at some point during the past seven years. The astronauts were evaluated prior to their ISS spaceflights, and then six and 12 months after their return to Earth.

The team took bone scans of specific anatomical areas, namely the tibia, or shinbone, and the forearm. This allowed the scientists to measure the susceptibility of these bones to fracturing (or “failure load,” in the vernacular of kinesiologists), and the amount of bone mineral content and the thickness of bone tissue. They also recorded the astronauts’ workout routines during and after their space missions, including exercises such as deadlifts, running on a treadmill, and cycling.

Of the 17 astronauts studied, 16 exhibited incomplete recoveries of their shinbones (measures of their forearms didn’t really differ a year after the spaceflights). On average, the astronauts exhibited a tibia failure load capacity of 10,579 newtons prior to their spaceflights, but that dropped to 10,084 newtons upon their immediate return to Earth, for a loss of 495 newtons. The astronauts did manage to make a partial recovery in the year following their return, but they were still 152 newtons below their preflight tibia failure load values.

Their bone densities also took a beating. The astronauts had bone densities averaging 326 milligrams per cubic centimeter prior to their time in space, but this dropped to 282.5 mg per cubic centimeter upon their return—a drop of 43.5 mg per cubic centimeter.

“Our findings indicate that microgravity induces irreversible damage to bone strength, density, and trabecular bone microarchitecture,” the scientists wrote in their study. The trabecular bone is a “highly porous form of bone tissue that is organized into a network of interconnected rods and plates,” the function of which is to provide strength and channel external loads away from joints, according to unrelated research.

Unsurprisingly, the bone measures worsened depending on the length of the mission. The eight astronauts who were on the ISS for longer than six months recovered significantly less than those who participated in shorter missions, according to the study. At the same time, the astronauts who recovered the most tibia bone mineral density performed the most in-flight deadlift exercises.

“Since cramped quarters will be a limiting factor on future exploration-class missions, exercise equipment will need to be optimized for a smaller footprint,” the scientists write. “Resistance exercise training (particularly deadlifts and other lower-body exercises) will remain a mainstay for mitigating bone loss; however, adding a jumping exercise to on-orbit regimens may further prevent bone loss and reduce daily exercise time.”

These are important findings, particularly as NASA, through its upcoming Artemis program, is wanting to build a sustainable and prolonged presence on and around the Moon. The new research also speaks to future crewed missions to Mars, which will likewise feature prolonged stays in space. In addition to muscle atrophy and the loss of bone strength, microgravity imposes detrimental affects on the heart, eyes, brain, spine, cells, and overall physical fitness. It’s vital that we learn about all the risks associated with spaceflight and the best ways to mitigate them.

More: Missions to Mars Shouldn’t Exceed Four Years Due to Radiation Risks, Scientists Say.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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