A pulsar orbited by a white dwarf star, which are both orbited by another white dwarf, provide confirmation of the principle of universality of free fall



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RELATED: This Portable Generator Produces Power and Clean Water From Human Waste

Making the current system bigger would offer one solution to collecting more water. But Kapustin said he and his team want to design more efficient MOFs to make the system smaller and portable. This summer, he and colleagues are testing a new design in California’s Death Valley.

“We think MOF based technology will be the only one that will produce actual water in arid regions of the world,” said Kapustin.

In very humid regions, fog collecting has become a popular way to capture water from the air. Typically, these systems are made of giant, passive mesh or nets, where water droplets cling, coalesce, and then stream down into buckets. But this method is quite inefficient, capturing just 1 to 3 percent of the water droplets in the air passing by.

A team at MIT, lead by associate professor of mechanical engineering Kripa Varanasi, has developed a way to increase the efficiency of fog collecting to nearly 99 percent. By emitting a pulse of electrically charged particles, or ions, into the air near the surface of a collector, which creates an electric field and also charges nearby water particles, compelling them toward the mesh of wires. In laboratory experiments the electrostatic charge in combination with a 2 inch by 2 inch mesh collected enough water droplets — created by a mist machine — to fill a 1 ounce beaker in 30 minutes. The team published their research in Science Advances.

Varanasi told Seeker he sees a couple of different applications for this technology and, to commercialize them, has started a company called Infinite Cooling, which recently won MIT's $100K Entrepreneurship Competition.

The first application focuses on power plant cooling towers that billow plumes of water vapor so dense they’re often mistaken for smoke. A 600 MW power plant operating at 55 percent capacity loses roughly 750 million gallons of water every year, said Varanasi. But a lightweight mesh dome fitted over the top of the tower could capture enough vapor to produce 150 million gallons of water.

“That’s a million dollars in savings for the plant,” said Varanasi.



RELATED: Drinking Water Database Reveals the Dirtiest — and Cleanest — Supplies in the US

Currently, the company is building a mesh dome over a geodesic frame for the cooling tower connected to MIT's Central Utility Plant, which generates 20 megawatts of energy for the campus. The dome should be installed by the end of the summer and Varanasi and his team will test its performance over the fall.

Since many power plants are located along coastlines in order to use seawater for cooling, Infinite Cooling’s technology could also be used to desalinate seawater. “The amount of energy we use is 50 times lower than reverse osmosis desalination,” said Varanasi. “We think this is the way to desalinate.”

Water is a crucial resource that everybody needs but nobody wants to pay for, said Varanasi. Instead of developing new membrane technology or filtration, he and his team want to focus on the nexus of energy and water to create an entirely new business.

“We want to disrupt the water market and address global water scarcity,” he said.

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Mon, 11 Jun 2018 15:45:29 -0500
The US Centers for Disease Control and Prevention reported significant increases in the suicide rate in 44 of 50 states. no-reply@thrillist.com AFPAFPhttp://www.seeker.com/health/us-suicide-rate-jumps-30-percent-amid-bourdain-spade-deaths?utm_medium=RSS&utm_source=feeds Credit: Slavica via Getty Images
The suicide rate across the United States has risen 30 percent since 1999, and nearly 45,000 people took their lives in 2016, officials said Thursday.

Suicide presents a "growing public health problem," with significant increases in 44 of the 50 states, said the report by the US Centers for Disease Control and Prevention (CDC).

Earlier this week, American handbag designer Kate Spade, 55, took her own life, sparking renewed calls for mental health awareness and suicide prevention.

Suicide is "a tragedy for families and communities across the country," said CDC principal deputy director Anne Schuchat.

"From individuals and communities to employers and healthcare professionals, everyone can play a role in efforts to help save lives and reverse this troubling rise in suicide."

Suicide is the 10th leading cause of death in the United States, and is rarely caused by a single factor, experts say.

The study, which spanned 1999 to 2016, found that more than half of people who killed themselves did not have a known diagnosed mental health condition at the time of death.

Contributing factors included "relationship problems or loss, substance misuse; physical health problems; and job, money, legal, or housing stress," said the report.

The most common method of suicide involved firearms.

RELATED: Pressure to Be Perfect Could Increase the Risk of Suicide

The highest suicide rate from 2014-2016 was in Montana, where 29.2 residents per 100,000 people took their own lives. It was lowest in the US capital, Washington DC, with 6.9 suicides per 100,000 residents per year.

The biggest spike in suicides since 1999 was in North Dakota, where suicides rose 57 percent.

A total of 25 states had suicide rate increases of more than 30 percent in that span.

The CDC, the top US public health agency, said individual states need to do more to boost suicide prevention "and address the range of factors contributing to suicide."

"This requires coordination and cooperation from every sector of society: government, public health, healthcare, employers, education, media, and community organizations," it added, urging those interested in learning the warning signs to visit www.BeThe1to.com.

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Fri, 08 Jun 2018 15:54:57 -0500
The twin findings further prospects for one day discovering evidence of life on the Red Planet. no-reply@thrillist.com Nancy AtkinsonNancy Atkinsonhttp://www.seeker.com/space/nasas-curiosity-rover-detects-methane-and-organic-material-on-mars?utm_medium=RSS&utm_source=feeds Credit: NASA/JPL-Caltech/MSSS
NASA announced on Thursday two discoveries which further the prospects that scientists might one day find evidence of life on Mars.

First, data from NASA’s Curiosity rover has shown for the first time that methane levels in the martian atmosphere have a seasonal cycle. Scientists analyzed three years of atmospheric measurements taken by Curiosity and found low, background levels of methane that rose during summer in the northern hemisphere.

Also, scientists detected organic material preserved in rocks in Gale Crater, which is thought to be an ancient lakebed. The find suggests the planet could have supported ancient life.

The research has been published in the journal Science.

Chris Webster of NASA’s Jet Propulsion Laboratory said the methane discovery showed a discernible pattern in seasonal concentrations of the gas.

“We see a low background level of methane from winter to summer,” he said, “but the seasonal cycle changes by a factor of three, which is a huge change, and was completely unexpected.”

The methane could come from a biological source, but is likely stored in crystals called clathrates, which release the methane into the atmosphere during warmer summer weather.

“The detection of methane is always exciting because 95 percent of Earth’s methane is produced by biology, and so there has always been this interest in Mars methane” Webber said. “Our data shows that something is happening today that is producing it.”


Credit: Curiosity has detected seasonal changes in methane at Gale Crater using its SAM instrument.
Scientists first detected methane on Mars in 1999. Then, in 2014, Curiosity detected methane spikes, but the fluctuation in methane levels didn’t appear to fit a pattern.

Webber told Seeker the latest announcement is different than past methane discoveries.

“Now we’ve measured a consistent background level, with seasonal spikes of methane,” he said. “The spikes are very important, because the change is so dramatic, some process is causing large pulses of the gas being released.”

The methane concentrations ranged from 0.24 to 0.65 parts per billion.



RELATED: New NASA Lander Will Study Marsquakes and the Red Planet’s Mysterious Volcanism

The organic material detected by Curiosity, according to Jen Eigenbrode of NASA’s Goddard Space Flight Center, had been preserved in martian rocks for over 3 billion years.

Though the molecules are organic, the find doesn’t confirm the existence of life on Mars.

“Curiosity has not determined the source of the organic molecules,” said Eigenbrode. “And we have not determined whether it contains a record of ancient life, or was food for life. But it does give us chemical clues to planetary conditions and processes.”

The source of the organic material could have a meteorite crashing into the Red Planet, for example.


Credit: Curiosity has discovered ancient organic molecules in Gale Crater.
Eigenbrode said the molecules are amazingly robust. They were found close to the surface and were exposed to ionizing radiation, which can degrade organics.

“We think they haven’t changed over time, as this form of organic matter is resistant to changes,” she said. “But if life was on early Mars and other conditions were favorable, this means the organic biosignatures would be preserved.”

A drill on the Curiosity rover made a 5 centimeter hole in mudstones in Gale Crater at sites called Mojave and Confidence Hills. The rover then heated the rock samples to over 900 degrees Fahrenheit (500 degrees Celsius) and analyzed the molecules that were released. The process revealed the presence of several organic molecules, including carbon, thiophenes, benzene, toluene, and small carbon chains, such as propane or butene.

Like the methane discovery, NASA had also announced in 2014 the detection of organic molecules.

“In 2014, we reported the detection of chlorinated molecules, which is a significant discovery,” Eigenbrode told Seeker. “We had hoped we would find it with the Viking landers in the 1970’s, but we didn’t. While Curiosity’s first detection in 2014 was not what you typically find in natural samples, it did give us a lot of motivation to keep looking because we thought there had to be other layers of organic molecules.”

RELATED: Oceans on Mars Appear to Have Formed Much Earlier Than Previously Thought

Curiosity found new organic layers just four miles away from the first site. And Eigenbrode said the new find provides another boost for research on the Red Planet.

Ashwin Vasavada, project scientist with the Curiosity team, said the longevity of the Curiosity mission was key to both finds

“Without having the rover surface for over 6 years, we couldn’t have made these detections,” he said. “And these findings give upcoming missions like ESA’s ExoMars and the Mars 2020 rover a lot of work ahead.”

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Fri, 08 Jun 2018 15:13:55 -0500
A widely studied collision of two neutron stars, detected in August 2017, now appears to have created a black hole, supporting a long-held scientific theory.no-reply@thrillist.com Chelsea Gohd, Space.comChelsea Gohd, Space.comhttp://www.seeker.com/space/observations-of-neutron-star-collision-appear-to-show-the-creation-of-a-black-hole?utm_medium=RSS&utm_source=feeds Credit: NASA/CXC/M.Weiss
In August 2017, for the first time ever, scientists spotted gravitational waves generated by the merger of two superdense stellar corpses known as neutron stars.

This landmark find was a major step forward in understanding the cosmos, astronomers have stressed.

At the time, scientists suggested that this dramatic event, officially cataloged as GW170817, could have created a black hole — and a new analysis backs this supposition up. [Neutron-Star Crash: A Gravitational Waves Discovery in Pictures]

In the new study, researchers analyzed data gathered by NASA's Chandra X-ray Observatory after the gravitational waves — ripples in space-time first predicted by Albert Einstein a century ago — were detected by the Laser Interferometer Gravitational Wave Observatory (LIGO) project.

LIGO data revealed that the object created by the neutron-star merger is about 2.7 times the mass of the sun. It is therefore either the lowest-mass black hole ever identified, or the most massive neutron star, the researchers said.

But the study team is putting its money on the black hole interpretation. If the two neutron stars collided to form a single, heavier neutron star, the resulting object would likely have a strong magnetic field that produces bright X-ray emissions, researchers said. However, the Chandra observations revealed low X-ray levels.

"We may have answered one of the most basic questions about this dazzling event: What did it make?" study co-author Pawan Kumar, of the University of Texas at Austin, said in a statement. "Astronomers have long suspected that neutron star mergers would form a black hole and produce bursts of radiation, but we lacked a strong case for it until now."


Credit: Illustration: NASA/CXC/M. Weiss; Images: NASA/CXC/Trinity University/D. Pooley et al.
If this hypothesis is confirmed, it could shed light on black holes, the darkest objects in the universe. (The lightest-known black holes harbor a minimum of four to five times the mass of the sun.)

Not all black holes form the same way, but this ultra-low-mass black hole would have taken shape after two supernova explosions left two neutron stars in a close-enough orbit for gravitational-wave radiation to help them collide — a strange and complicated journey, study team members said.

It would also be very interesting if astronomers determined that GW170817 generated a single gigantic neutron star. Such a result would challenge theories about the structure and formation of these exotic objects, researchers said.

"GW170817 is the astronomical event that keeps on giving," study co-author J. Craig Wheeler, also of the University of Texas, said in the statement. "We are learning so much about the astrophysics of the densest known objects from this one event."

Fellow study co-author Bruce Grossan, of the University of California at Berkeley, voiced similar sentiments.

"At the beginning of my career, astronomers could only observe neutron stars and black holes in our own galaxy, and now we are observing these exotic stars across the cosmos," Grossan said. "What an exciting time to be alive, to see instruments like LIGO and Chandra showing us so many thrilling things nature has to offer."

The new study was published online May 31 in The Astrophysical Journal Letters.

Original article on Space.com.

Editor's Recommendations
How Gravitational Waves Work (Infographic)
No Escape: Dive Into a Black Hole (Infographic)
Inside a Neutron Star (Infographic)

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Thu, 07 Jun 2018 15:48:25 -0500
The engineered cells mobilize adjacent, natural cells into complex structures.no-reply@thrillist.com Glenn McDonaldGlenn McDonaldhttp://www.seeker.com/health/genetically-engineered-cells-command-natural-ones-to-repair-and-grow?utm_medium=RSS&utm_source=feeds Credit: Wendell Lim/UCSF
The field of developmental biology is dedicated to one of the fundamental wonders of the universe: How do complex biological structures — brains, arms, people — emerge from a single fertilized egg?

It's a puzzler, all right. But new research out of the University of California, San Francisco suggests that we may have just cracked the first part of the complex code that informs embryonic development.

Using a kind of genetically modified “boss” cell, the UCSF team was able to get other groups of individual cells to self-organize into multi-layered structures. These structures are similar — and in some cases identical — to simple organisms like bacterium or the tissues in the very first stages of human embryonic development.

The key to the new technique, according to researchers, is a customizable synthetic signaling molecule called SynNotch, short for synthetic Notch receptor. The SynNotch cell acts as a kind of middle manager molecule and allows researchers (senior management) to program nearby organic cells (salaried workers) with specific sets of instructions.

For example, the researchers engineered several groups of neighboring cells to produce Velcro-like adhesion molecules called cadherins along with fluorescent marker proteins. By sending specific directions through the SynNotch cells, researchers convinced the other cells to change color and self-organize into multi-layered structures similar to simple organisms or, significantly, human tissue.

The new research was published in the journal Science.



RELATED: Bioengineers Program Cells to Fold Into 3D Shapes

One of the potential applications of the technology is a very big deal. In fact, it's a kind of Holy Grail for developmental biology: The ability to grow entire replacement organs or limbs for wound repair or transplant.

According to the study's senior author Wendell Lim, chair of the department of cellular and molecular pharmacology at UCSF, the SynNotch technique is fundamentally different from other current tissue-generation techniques.

"People talk about 3D-printing organs, but that is really quite different from how biology builds tissues,” Lim said in a statement issued with the new research. “Imagine if you had to build a human by meticulously placing every cell just where it needs to be and gluing it in place. It's equally hard to imagine how you would print a complete organ, then make sure it was hooked up properly to the bloodstream and the rest of the body.”

If biologists can figure a way to program increasingly complex structures, then natural cellular development would handle all the heavy lifting. Scientists would be, in effect, simply supplying the blueprints.

“The beauty of self-organizing systems is that they are autonomous and compactly encoded,” Lim said. “You put in one or a few cells, and they grow and organize, taking care of the microscopic details themselves."

One interesting note: Even though the SynNotch technique is in its very early stages, the research team was able to engineer some surprisingly complex and important structures.

For instance, they were able to generate cells that formed the beginnings of what is called “polarity” in biological systems. These are the distinct front-back, left-right, head-toe axes that define the body plans of  organisms — humans included.

By deploying different types of cadherin adhesion molecules, the research team was able to convince cellular assemblages to divide into "head" and "tail" sections, or to produce four distinct radial "arms."

Insert your own Frankenstein joke here.  

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Thu, 07 Jun 2018 15:06:11 -0500
The sex of marine turtles is influence by the temperature of the nests in which eggs incubate. And plastic pollution may be making those nests hotter.no-reply@thrillist.com Mariana Fuentes, The ConversationMariana Fuentes, The Conversationhttp://www.seeker.com/earth/microplastic-pollution-may-cause-more-female-turtle-births?utm_medium=RSS&utm_source=feeds Credit: Orjan F. Ellingvag/Corbis via Getty Images
Have you ever considered that small pieces of plastic less than 5 millimeters long, or smaller than a pencil eraser head, called microplastics, can affect large marine vertebrates like sea turtles?

My research team first discovered this disturbing fact when we started to quantify the amount and type of microplastic at loggerhead nesting grounds in the northern Gulf of Mexico, between St. Joseph State Park and Alligator Point in Florida.

Microplastics, which are created by the breakdown of larger plastic pieces into smaller ones, or manufactured as microbeads or fibers for consumer products, can change the composition of sandy beaches where marine turtles nest. Marine turtles, which are listed under the Endangered Species Act, lay their eggs in coastal areas, and the environment in which their eggs incubate can influence hatching success, the gender and size of hatchlings.

In particular, the sex of marine turtle eggs is determined by the sand temperature during egg incubation. Warmer sand produces more females and cooler sand, more males. Temperatures between approximately 24-29.5 degrees Celsius produce males and above 29.5 to 34°C, females. Since plastics warm up when exposed to heat, when combined with sand, microplastics may increase the sand temperature, especially if the pigment of the plastic is dark. This could potentially affect the nesting environment of marine turtles, biasing the sex ratio of turtles toward producing only females and affecting the future reproductive success of the species.


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