afro-dominicano:


Milky Way Madness At Mesa Arch by Mike Berenson
"Night photographer Mike Berenson provides his own "icing on the cake" in this flashlight illuminated, starry night image with Milky Way skies at Mesa Arch in Canyonlands National Park, Utah. Mike captured this image with a Nikon D800 and Bower 14mm f/2.8 Lens on August 19th, 2014."
high resolution →

afro-dominicano:

Milky Way Madness At Mesa Arch by Mike Berenson

"Night photographer Mike Berenson provides his own "icing on the cake" in this flashlight illuminated, starry night image with Milky Way skies at Mesa Arch in Canyonlands National Park, Utah. Mike captured this image with a Nikon D800 and Bower 14mm f/2.8 Lens on August 19th, 2014."

starstuffblog:

Powerful, Pulsating Core of Star 
The blue dot in this image marks the spot of an energetic pulsar — the magnetic, spinning core of star that blew up in a supernova explosion. NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, discovered the pulsar by identifying its telltale pulse — a rotating beam of X-rays, that like a cosmic lighthouse, intersects Earth every 0.2 seconds.
The pulsar, called PSR J1640-4631, lies in our inner Milky Way galaxy about 42,000 light-years away. It was originally identified by as an intense source of gamma rays by the High Energy Stereoscopic System (H.E.S.S.) in Namibia. NuSTAR helped pin down the source of the gamma rays to a pulsar.
The other pink dots in this picture show low-energy X-rays detected by NASA’s Chandra X-ray Observatory.
In this image, NuSTAR data is blue and shows high-energy X-rays with 3 to 79 kiloelectron volts; Chandra data is pink and shows X-rays with 0.5 to 10 kiloeletron volts.
The background image shows infrared light and was captured by NASA’s Spitzer Space Telescope.
Image credit: NASA/JPL-Caltech/SAO
high resolution →

starstuffblog:

Powerful, Pulsating Core of Star

The blue dot in this image marks the spot of an energetic pulsar — the magnetic, spinning core of star that blew up in a supernova explosion. NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, discovered the pulsar by identifying its telltale pulse — a rotating beam of X-rays, that like a cosmic lighthouse, intersects Earth every 0.2 seconds.

The pulsar, called PSR J1640-4631, lies in our inner Milky Way galaxy about 42,000 light-years away. It was originally identified by as an intense source of gamma rays by the High Energy Stereoscopic System (H.E.S.S.) in Namibia. NuSTAR helped pin down the source of the gamma rays to a pulsar.

The other pink dots in this picture show low-energy X-rays detected by NASA’s Chandra X-ray Observatory.

In this image, NuSTAR data is blue and shows high-energy X-rays with 3 to 79 kiloelectron volts; Chandra data is pink and shows X-rays with 0.5 to 10 kiloeletron volts.

The background image shows infrared light and was captured by NASA’s Spitzer Space Telescope.

Image credit: NASA/JPL-Caltech/SAO

neuromorphogenesis:

Schizophrenia not a single disease but multiple genetically distinct disorders

About 80 percent of the risk for schizophrenia is known to be inherited, but scientists have struggled to identify specific genes for the condition. Now, in a novel approach analyzing genetic influences on more than 4,000 people with schizophrenia, the research team has identified distinct gene clusters that contribute to eight different classes of schizophrenia.

“Genes don’t operate by themselves,” said C. Robert Cloninger, MD, PhD, one of the study’s senior investigators. “They function in concert much like an orchestra, and to understand how they’re working, you have to know not just who the members of the orchestra are but how they interact.” 

Cloninger, the Wallace Renard Professor of Psychiatry and Genetics, and his colleagues matched precise DNA variations in people with and without schizophrenia to symptoms in individual patients. In all, the researchers analyzed nearly 700,000 sites within the genome where a single unit of DNA is changed, often referred to as a single nucleotide polymorphism (SNP). They looked at SNPs in 4,200 people with schizophrenia and 3,800 healthy controls, learning how individual genetic variations interacted with each other to produce the illness. 

In some patients with hallucinations or delusions, for example, the researchers matched distinct genetic features to patients’ symptoms, demonstrating that specific genetic variations interacted to create a 95 percent certainty of schizophrenia. In another group, they found that disorganized speech and behavior were specifically associated with a set of DNA variations that carried a 100 percent risk of schizophrenia.

“What we’ve done here, after a decade of frustration in the field of psychiatric genetics, is identify the way genes interact with each other, how the ‘orchestra’ is either harmonious and leads to health, or disorganized in ways that lead to distinct classes of schizophrenia,” Cloninger said. 

Although individual genes have only weak and inconsistent associations with schizophrenia, groups of interacting gene clusters create an extremely high and consistent risk of illness, on the order of 70 to 100 percent. That makes it almost impossible for people with those genetic variations to avoid the condition. In all, the researchers identified 42 clusters of genetic variations that dramatically increased the risk of schizophrenia.

 “In the past, scientists had been looking for associations between individual genes and schizophrenia,” explained Dragan Svrakic, PhD, MD, a co-investigator and a professor of psychiatry at Washington University. “When one study would identify an association, no one else could replicate it. What was missing was the idea that these genes don’t act independently. They work in concert to disrupt the brain’s structure and function, and that results in the illness.”

Svrakic said it was only when the research team was able to organize the genetic variations and the patients’ symptoms into groups that they could see that particular clusters of DNA variations acted together to cause specific types of symptoms.

Then they divided patients according to the type and severity of their symptoms, such as different types of hallucinations or delusions, and other symptoms, such as lack of initiative, problems organizing thoughts or a lack of connection between emotions and thoughts. The results indicated that those symptom profiles describe eight qualitatively distinct disorders based on underlying genetic conditions. 

The investigators also replicated their findings in two additional DNA databases of people with schizophrenia, an indicator that identifying the gene variations that are working together is a valid avenue to explore for improving diagnosis and treatment. 

By identifying groups of genetic variations and matching them to symptoms in individual patients, it soon may be possible to target treatments to specific pathways that cause problems, according to co-investigator Igor Zwir, PhD, research associate in psychiatry at Washington University and associate professor in the Department of Computer Science and Artificial Intelligence at the University of Granada, Spain.

And Cloninger added it may be possible to use the same approach to better understand how genes work together to cause other common but complex disorders.

“People have been looking at genes to get a better handle on heart disease, hypertension and diabetes, and it’s been a real disappointment,” he said. “Most of the variability in the severity of disease has not been explained, but we were able to find that different sets of genetic variations were leading to distinct clinical syndromes. So I think this really could change the way people approach understanding the causes of complex diseases.”

rhamphotheca:

What Do You Get When You Cross a Dragon With a Pelican?
by Sid Perkins
An ancient flying reptile (dubbed Ikrandraco avatar) may have had a feeding style akin to that of modern birds known as skimmers, which occasionally swoop along the water’s surface to snatch fish swimming there, a new study suggests.
Fossils of the newly described pterosaur were unearthed from 120-million-year-old rocks at two sites in northeastern China. The front portion of the creature’s lower jaw had a deep, thin, crescent-shaped keel (artist’s representation above) that may have been covered with keratin, akin to the beaks of modern birds. At the end of that bony keel, researchers noted a peculiar hook-shaped projection—a feature not seen in any other pterosaur, or indeed in any other vertebrate, living or extinct—that might have served as an anchor for soft tissue.
That distinctive bony projection suggests the pterosaur’s most distinct feature may have been a pelicanlike throat pouch that could hold fish gleaned from lakes and rivers, the researchers suggest today in Scientific Reports…
(read more: Science News/AAAS)
high resolution →

rhamphotheca:

What Do You Get When You Cross a Dragon With a Pelican?

by Sid Perkins

An ancient flying reptile (dubbed Ikrandraco avatar) may have had a feeding style akin to that of modern birds known as skimmers, which occasionally swoop along the water’s surface to snatch fish swimming there, a new study suggests.

Fossils of the newly described pterosaur were unearthed from 120-million-year-old rocks at two sites in northeastern China. The front portion of the creature’s lower jaw had a deep, thin, crescent-shaped keel (artist’s representation above) that may have been covered with keratin, akin to the beaks of modern birds. At the end of that bony keel, researchers noted a peculiar hook-shaped projection—a feature not seen in any other pterosaur, or indeed in any other vertebrate, living or extinct—that might have served as an anchor for soft tissue.

That distinctive bony projection suggests the pterosaur’s most distinct feature may have been a pelicanlike throat pouch that could hold fish gleaned from lakes and rivers, the researchers suggest today in Scientific Reports

(read more: Science News/AAAS)

Astrophysicists Identify The “Habitable” Regions Of The Entire Universe
It’s not just stars and galaxies that have habitable zones. Some regions of universe are more life-friendly than others
On 27 December 2004, the neutron star SGR 1806–20 in the Milky Way flared up bathing the Earth in such vast quantities of radiation that our planet’s magnetosphere briefly flickered. The event was noteworthy because it was the first time astronomers had witnessed an object outside the Solar System directly influencing the Earth.
Gamma ray bursts are among the most powerful events in the universe. And although the SGR 1806 -20 flare was relatively mild, it was an unwelcome reminder that life on this planet is constantly threatened by events of unimaginable power.
Continue Reading
high resolution →

Astrophysicists Identify The “Habitable” Regions Of The Entire Universe

It’s not just stars and galaxies that have habitable zones. Some regions of universe are more life-friendly than others

On 27 December 2004, the neutron star SGR 1806–20 in the Milky Way flared up bathing the Earth in such vast quantities of radiation that our planet’s magnetosphere briefly flickered. The event was noteworthy because it was the first time astronomers had witnessed an object outside the Solar System directly influencing the Earth.

Gamma ray bursts are among the most powerful events in the universe. And although the SGR 1806 -20 flare was relatively mild, it was an unwelcome reminder that life on this planet is constantly threatened by events of unimaginable power.

Continue Reading

plays

christinetheastrophysicist:

Venus’ Interesting Magnetic Structure

Venus may be similar to Earth in size and mass, but there are differences between the two planets. One difference is the magnetic field. On Venus, a magnetic field isn’t generated by the planet, like Earth’s. It is actually an induced magnetosphere, a region of charged particles around the planet formed by a reaction between Venus’ ionosphere and the solar wind. New research shows that there are holes void of magnetically charged plasma in a region where such plasma is expected to be.

The holes were first noticed when the Pioneer Venus Orbiter moved around the backside of the planet back in 1978. Since then, the holes have not been detected again.

Recently, researchers studying data from the Venus Express orbiter decided to look for the holes again. They found them and realized that they were more common than initially thought, visible over a broad range of solar activity.

When the solar wind hits Venus, it wraps around the planet and a long tail extends behind it. This is what creates the magnetosphere. The Venus Express orbiter took measurements of the magnetic field strength and found variations that indicated the presence of these holes. The observations suggest that these holes are actually not just holes, but take the shape of long cylinders directed out towards space.

But what is causing these cylinders to form? In addition to the solar wind wrapping around the planet to create the magnetosphere, the researchers propose that the magnetic field lines from the solar wind is able to continue into the planet and wrap around its core, something that is also seen on the Moon. As a result, the electrically charged plasma is pushed to the sides and this is what created the two cylinders found behind the planet by the orbiters.

More information can been seen in the NASA video above, the press release, and the journal paper (paywall).

Brainstorm in a teacup: can epilepsy fuel creativity?
By: Dan Mitchell
Epilepsy can be very disruptive and debilitating, but can it also spur creativity? If treatments suppress comedic inspiration and this directly affects your job, is it worth it?
I’m an epileptic.
It’s not how I define myself, but I am writing about epilepsy, so I think pointing out the fact that I am speaking from experience is acceptable.
I may not define myself by my epilepsy but it’s a big part of my life. It affects my life on a daily basis. Because of the epilepsy I can’t drive, can’t pull all-nighters or get up really early just in case I have a seizure. It’s frustrating at times, though I will gladly milk the not getting up early thing when I can, eg bin day.
Continue Reading

Brainstorm in a teacup: can epilepsy fuel creativity?

By: Dan Mitchell

Epilepsy can be very disruptive and debilitating, but can it also spur creativity? If treatments suppress comedic inspiration and this directly affects your job, is it worth it?

I’m an epileptic.

It’s not how I define myself, but I am writing about epilepsy, so I think pointing out the fact that I am speaking from experience is acceptable.

I may not define myself by my epilepsy but it’s a big part of my life. It affects my life on a daily basis. Because of the epilepsy I can’t drive, can’t pull all-nighters or get up really early just in case I have a seizure. It’s frustrating at times, though I will gladly milk the not getting up early thing when I can, eg bin day.

Continue Reading

neurosciencestuff:

Brain Imaging Research Pinpoints Neurobiological Basis for Key Symptoms Associated with Post-Traumatic Stress Disorder Like Listlessness and Emotional Detachment in Trauma Victims
In a novel brain-imaging study among trauma victims, researchers at NYU Langone Medical Center have linked an opioid receptor in the brain — associated with emotions — to a narrow cluster of trauma symptoms, including sadness, emotional detachment and listlessness. The study, published online today in the journal JAMA Psychiatry, holds important implications for targeted, personalized treatment of post-traumatic stress disorder, or PTSD, a psychiatric condition affecting more than 8 million Americans that can cause a wide range of debilitating psychiatric symptoms.
“Our study points toward a more personalized treatment approach for people with a specific symptom profile that’s been linked to a particular neurobiological abnormality,” says lead author Alexander Neumeister, MD, director of the molecular imaging program in the Departments of Psychiatry and Radiology at NYU School of Medicine, and Co-Director of NYU Langone’s Steven and Alexandra Cohen Veterans Center for the Study of Post-Traumatic Stress Disorder and Traumatic Brain Injury. “Understanding more about where and how symptoms of PTSD manifest in the brain is a critical part of research efforts to develop more effective medications and treatment modalities.”
The new study confirms a growing body of evidence linking a particular set of symptoms to specific brain circuits and chemicals, and bolsters a shift within the field of psychiatry away from “one-size-fits-all treatments” and toward more individualized medication regimens that target highly specific neurobiological components. “We know from previous clinical trials that antidepressants, for example, do not work well for dysphoria and the numbing symptoms often found in PTSD,” Dr. Neumeister added. “Currently available antidepressants are just not linked specifically enough to the neurobiological basis of these symptoms in PTSD. Going forward, our study will help pave the way toward development of better options.”
“People with cancer have a variety of different treatment options available based on the type of cancer that they have,” adds Dr. Neumeister. “We aim to do the same thing in psychiatry. We’re deconstructing PTSD symptoms, linking them to different brain dysfunction, and then developing treatments that target those symptoms. It’s really a revolutionary step forward that has been supported by the National Institute of Mental Health (NIMH) over the past few years in their Research Domain Criteria Project.”
The study, funded by the National Institute of Mental Health (NIMH), compared the brain scans of healthy volunteers with those of clinically diagnosed trauma victims with PTSD, major depression, and generalized anxiety disorder whose symptoms ranged from emotional detachment to isolation. Participants received a harmless radioactive tracer that binds to and illuminates a class of opioid receptors, known as kappa, when exposed to high-resolution positron emission tomography (PET). Kappa opioid receptors bind a potent natural opioid known as dynorphin, which is released by the body during times of stress to help relieve dysphoria or numbing.
Chronic exposure to stress, such as the case with PTSD, taxes kappa opioid receptors, however, causing the receptors to retract inside cells, leaving dynorphin without a place to dock. As a result, patients can experience dysphoria, characterized by feelings of hopelessness, detachment and emotional unease.
Results showed that fewer available kappa opioid receptors in the brain regions believed to govern emotions were associated with more intense feelings of dysphoria, but not feelings of anxious arousal. The findings confirm previous studies in animals linking the opioid-receptor system expressed in these specific brain regions to symptoms of dysphoria. The study also found an association between lower levels of cortisol, a stress hormone, and unavailable kappa opioid receptors, suggesting a new role for cortisol as a biomarker for certain types of PTSD symptoms.
“This is the first brain-imaging study to explore any psychiatric condition using a protein that binds to the kappa opioid receptor system,” notes Dr. Neumeister, who says the data support clinical trials under way at NYU Langone and other institutions of new medications that target kappa opioid receptors and other brain systems that can be linked to specific symptoms in trauma survivors. Such medications could be widely available for the treatment of PTSD in the future if ongoing clinical trials yield encouraging results.
(Image: Alamy)
high resolution →

neurosciencestuff:

Brain Imaging Research Pinpoints Neurobiological Basis for Key Symptoms Associated with Post-Traumatic Stress Disorder Like Listlessness and Emotional Detachment in Trauma Victims

In a novel brain-imaging study among trauma victims, researchers at NYU Langone Medical Center have linked an opioid receptor in the brain — associated with emotions — to a narrow cluster of trauma symptoms, including sadness, emotional detachment and listlessness. The study, published online today in the journal JAMA Psychiatry, holds important implications for targeted, personalized treatment of post-traumatic stress disorder, or PTSD, a psychiatric condition affecting more than 8 million Americans that can cause a wide range of debilitating psychiatric symptoms.

“Our study points toward a more personalized treatment approach for people with a specific symptom profile that’s been linked to a particular neurobiological abnormality,” says lead author Alexander Neumeister, MD, director of the molecular imaging program in the Departments of Psychiatry and Radiology at NYU School of Medicine, and Co-Director of NYU Langone’s Steven and Alexandra Cohen Veterans Center for the Study of Post-Traumatic Stress Disorder and Traumatic Brain Injury. “Understanding more about where and how symptoms of PTSD manifest in the brain is a critical part of research efforts to develop more effective medications and treatment modalities.”

The new study confirms a growing body of evidence linking a particular set of symptoms to specific brain circuits and chemicals, and bolsters a shift within the field of psychiatry away from “one-size-fits-all treatments” and toward more individualized medication regimens that target highly specific neurobiological components. “We know from previous clinical trials that antidepressants, for example, do not work well for dysphoria and the numbing symptoms often found in PTSD,” Dr. Neumeister added. “Currently available antidepressants are just not linked specifically enough to the neurobiological basis of these symptoms in PTSD. Going forward, our study will help pave the way toward development of better options.”

“People with cancer have a variety of different treatment options available based on the type of cancer that they have,” adds Dr. Neumeister. “We aim to do the same thing in psychiatry. We’re deconstructing PTSD symptoms, linking them to different brain dysfunction, and then developing treatments that target those symptoms. It’s really a revolutionary step forward that has been supported by the National Institute of Mental Health (NIMH) over the past few years in their Research Domain Criteria Project.”

The study, funded by the National Institute of Mental Health (NIMH), compared the brain scans of healthy volunteers with those of clinically diagnosed trauma victims with PTSD, major depression, and generalized anxiety disorder whose symptoms ranged from emotional detachment to isolation. Participants received a harmless radioactive tracer that binds to and illuminates a class of opioid receptors, known as kappa, when exposed to high-resolution positron emission tomography (PET). Kappa opioid receptors bind a potent natural opioid known as dynorphin, which is released by the body during times of stress to help relieve dysphoria or numbing.

Chronic exposure to stress, such as the case with PTSD, taxes kappa opioid receptors, however, causing the receptors to retract inside cells, leaving dynorphin without a place to dock. As a result, patients can experience dysphoria, characterized by feelings of hopelessness, detachment and emotional unease.

Results showed that fewer available kappa opioid receptors in the brain regions believed to govern emotions were associated with more intense feelings of dysphoria, but not feelings of anxious arousal. The findings confirm previous studies in animals linking the opioid-receptor system expressed in these specific brain regions to symptoms of dysphoria. The study also found an association between lower levels of cortisol, a stress hormone, and unavailable kappa opioid receptors, suggesting a new role for cortisol as a biomarker for certain types of PTSD symptoms.

“This is the first brain-imaging study to explore any psychiatric condition using a protein that binds to the kappa opioid receptor system,” notes Dr. Neumeister, who says the data support clinical trials under way at NYU Langone and other institutions of new medications that target kappa opioid receptors and other brain systems that can be linked to specific symptoms in trauma survivors. Such medications could be widely available for the treatment of PTSD in the future if ongoing clinical trials yield encouraging results.

(Image: Alamy)

science-junkie:

Hacked photosynthesis could boost crop yields
It is difficult to find fault with a process that can create food from sunlight, water and air, but for many plants, there is room for improvement. Researchers have taken an important step towards enhancing photosynthesis by engineering plants with enzymes from blue-green algae that speed up the process of converting carbon dioxide into sugars.The results, published today in Nature, surmount a daunting hurdle on the path to boosting plant yields — a goal that is taking on increasing importance as the world’s population grows.
Read more
high resolution →

science-junkie:

Hacked photosynthesis could boost crop yields

It is difficult to find fault with a process that can create food from sunlight, water and air, but for many plants, there is room for improvement. Researchers have taken an important step towards enhancing photosynthesis by engineering plants with enzymes from blue-green algae that speed up the process of converting carbon dioxide into sugars.
The results, published today in Nature, surmount a daunting hurdle on the path to boosting plant yields — a goal that is taking on increasing importance as the world’s population grows.

Read more

Monster black hole found in tiny galaxy
Discovery hints at twice as many supermassive black holes in the nearby Universe as previously thought.
Astronomers have for the first time found strong evidence for a giant black hole in a Lilliputian galaxy. The finding suggests that supermassive black holes could be twice as numerous in the nearby Universe as previously estimated, with many of them hidden at the centres of small, seemingly nondescript galaxies known as ultra-compact dwarfs.
Continue Reading
high resolution →

Monster black hole found in tiny galaxy

Discovery hints at twice as many supermassive black holes in the nearby Universe as previously thought.

Astronomers have for the first time found strong evidence for a giant black hole in a Lilliputian galaxy. The finding suggests that supermassive black holes could be twice as numerous in the nearby Universe as previously estimated, with many of them hidden at the centres of small, seemingly nondescript galaxies known as ultra-compact dwarfs.

Continue Reading

mindblowingscience:

This Massive Planet Is Causing Its Parent Star To Age Prematurely

There’s a gas giant located about 330 light-years from here that’s not only unusually large, it’s also orbiting its host star at an incredibly close distance. According to a new study, this combination of factors is wreaking havoc on the star’s innards.
The exoplanet is named WASP-18b and it’s about 10 times heavier than Jupiter. So this thing is absolutely huge. Not only that, it’s so close to its parent star, WASP-18, that it completes one single orbit in less than 23 hours. It’s one of the most extreme examples of a hot Jupiter that scientists have ever seen.
A team led by Ignazio Pillitteri of the Istituto Nazionale di Astrofisica (INAF)-Osservatorio Astronomico di Palermo in Italy dated WASP-18 between 500 million and 2 billion years old. That’s young by cosmological standards. By comparison, our sun, which is at its mid-life, is about 5 billion years old.
But here’s the thing: Younger stars tend to be more active, spewing out stronger magnetic fields, larger flares, and more intense X-ray emissions than their older counterparts. That’s why things are weird with WASP-18. The Chandra X-Ray Observatory explains:

Magnetic activity, flaring, and X-ray emission are linked to the star’s rotation, which generally declines with age. However, when astronomers took a long look with Chandra at WASP-18 they didn’t detect any X-rays. Using established relations between the magnetic activity and X-ray emission of stars, as well as its actual age, researchers determined WASP-18 is about 100 times less active than it should be.
"We think the planet is aging the star by wreaking havoc on its innards," said co-author Scott Wolk of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
The researchers argue that tidal forces created by the gravitational pull of the massive planet – similar to those the moon has on Earth’s tides, but on a much larger scale – may have disrupted the magnetic field of the star. [emphasis added]
The strength of the magnetic field depends on the amount of convection in the star, or how intensely hot gas stirs the interior of the star.
"The planet’s gravity may cause motions of gas in the interior of the star that weaken the convection," said co-author Salvatore Sciortino also of INAF-Osservatorio Astronomico di Palermo in Italy. "This has a domino effect that results in the magnetic field becoming weaker and the star to age prematurely."

WASP-18 is particularly vulnerable to the impact of tidal forces owing to its convection zone, which is narrower than most stars.
Read the entire study at the pre-print journal arXiv: “No X-rays from WASP-18. Implications for its age, activity, and the influence of its massive hot Jupiter”.
Image: X-ray: NASA/CXC/SAO/I.Pillitteri et al; Optical: DSS; Illustration: NASA/CXC/M.Weiss
high resolution →

mindblowingscience:

This Massive Planet Is Causing Its Parent Star To Age Prematurely

There’s a gas giant located about 330 light-years from here that’s not only unusually large, it’s also orbiting its host star at an incredibly close distance. According to a new study, this combination of factors is wreaking havoc on the star’s innards.

The exoplanet is named WASP-18b and it’s about 10 times heavier than Jupiter. So this thing is absolutely huge. Not only that, it’s so close to its parent star, WASP-18, that it completes one single orbit in less than 23 hours. It’s one of the most extreme examples of a hot Jupiter that scientists have ever seen.

A team led by Ignazio Pillitteri of the Istituto Nazionale di Astrofisica (INAF)-Osservatorio Astronomico di Palermo in Italy dated WASP-18 between 500 million and 2 billion years old. That’s young by cosmological standards. By comparison, our sun, which is at its mid-life, is about 5 billion years old.

But here’s the thing: Younger stars tend to be more active, spewing out stronger magnetic fields, larger flares, and more intense X-ray emissions than their older counterparts. That’s why things are weird with WASP-18. The Chandra X-Ray Observatory explains:

Magnetic activity, flaring, and X-ray emission are linked to the star’s rotation, which generally declines with age. However, when astronomers took a long look with Chandra at WASP-18 they didn’t detect any X-rays. Using established relations between the magnetic activity and X-ray emission of stars, as well as its actual age, researchers determined WASP-18 is about 100 times less active than it should be.

"We think the planet is aging the star by wreaking havoc on its innards," said co-author Scott Wolk of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

The researchers argue that tidal forces created by the gravitational pull of the massive planet – similar to those the moon has on Earth’s tides, but on a much larger scale – may have disrupted the magnetic field of the star. [emphasis added]

The strength of the magnetic field depends on the amount of convection in the star, or how intensely hot gas stirs the interior of the star.

"The planet’s gravity may cause motions of gas in the interior of the star that weaken the convection," said co-author Salvatore Sciortino also of INAF-Osservatorio Astronomico di Palermo in Italy. "This has a domino effect that results in the magnetic field becoming weaker and the star to age prematurely."

WASP-18 is particularly vulnerable to the impact of tidal forces owing to its convection zone, which is narrower than most stars.

Read the entire study at the pre-print journal arXiv: “No X-rays from WASP-18. Implications for its age, activity, and the influence of its massive hot Jupiter”.

Image: X-ray: NASA/CXC/SAO/I.Pillitteri et al; Optical: DSS; Illustration: NASA/CXC/M.Weiss

Special relativity aces time trial
'Time dilation' predicted by Einstein confirmed by lithium ion experiment.
Physicists have verified a key prediction of Albert Einstein’s special theory of relativity with unprecedented accuracy. Experiments at a particle accelerator in Germany confirm that time moves slower for a moving clock than for a stationary one.
The work is the most stringent test yet of this ‘time-dilation’ effect, which Einstein predicted. One of the consequences of this effect is that a person travelling in a high-speed rocket would age more slowly than people back on Earth.
Continue Reading
high resolution →

Special relativity aces time trial

'Time dilation' predicted by Einstein confirmed by lithium ion experiment.

Physicists have verified a key prediction of Albert Einstein’s special theory of relativity with unprecedented accuracy. Experiments at a particle accelerator in Germany confirm that time moves slower for a moving clock than for a stationary one.

The work is the most stringent test yet of this ‘time-dilation’ effect, which Einstein predicted. One of the consequences of this effect is that a person travelling in a high-speed rocket would age more slowly than people back on Earth.

Continue Reading

How your brain actually makes decisions while you sleep
The idea that during sleep our minds shut down from the outside world is ancient and one that is still deeply anchored in our view of sleep today, despite some everyday life experiences and recent scientific discoveries that would tend to prove that our brains don’t completely switch off from our environment.
On the contrary, our brains can keep the gate slightly open. For example, we wake up more easily when we hear our own name or a particularly salient sound such as an alarm clock or a fire alarm compared to equally loud but less relevant sounds.
Continue Reading
high resolution →

How your brain actually makes decisions while you sleep

The idea that during sleep our minds shut down from the outside world is ancient and one that is still deeply anchored in our view of sleep today, despite some everyday life experiences and recent scientific discoveries that would tend to prove that our brains don’t completely switch off from our environment.

On the contrary, our brains can keep the gate slightly open. For example, we wake up more easily when we hear our own name or a particularly salient sound such as an alarm clock or a fire alarm compared to equally loud but less relevant sounds.

Continue Reading

ucsdhealthsciences:

Scientists Discover Neurochemical Imbalance in Schizophrenia
Using human induced pluripotent stem cells (hiPSCs), researchers at Skaggs School of Pharmacy and Pharmaceutical Sciences at University of California, San Diego have discovered that neurons from patients with schizophrenia secrete higher amounts of three neurotransmitters broadly implicated in a range of psychiatric disorders.
The findings, reported online Sept. 11 in Stem Cell Reports, represent an important step toward understanding the chemical basis for schizophrenia, a chronic, severe and disabling brain disorder that affects an estimated one in 100 persons at some point in their lives. Currently, schizophrenia has no known definitive cause or cure and leaves no tell-tale physical marks in brain tissue.
"The study provides new insights into neurotransmitter mechanisms in schizophrenia that can lead to new drug targets and therapeutics,” said senior author Vivian Hook, PhD, a professor with Skaggs School of Pharmacy and UC San Diego School of Medicine.
In the study, UC San Diego researchers with colleagues at The Salk Institute for Biological Studies and the Icahn School of Medicine at Mount Sinai, N.Y., created functioning neurons derived from hiPSCs, themselves reprogrammed from skin cells of schizophrenia patients. The approach allowed scientists to observe and stimulate human neurons in ways impossible in animal models or human subjects.
Researchers activated these neurons so that they would secrete neurotransmitters – chemicals that excite or inhibit the transmission of electrical signals through the brain. The process was replicated on stem cell lines from healthy adults.
A comparison of neurotransmitters produced by the cultured “brain in a dish” neurons showed that the neurons derived from schizophrenia patients secreted significantly greater amounts of the catecholamine neurotransmitters dopamine, norepinephrine and epinephrine.
Catecholamine neurotransmitters are synthesized from the amino acid tyrosine and the regulation of these neurotransmitters is known to be altered in a variety of psychiatric diseases. Several psychotropic drugs selectively target the activity of these neurotransmitters in the brain.
In addition to documenting aberrant neurotransmitter secretion from neurons derived from patients with schizophrenia, researchers also observed that more neurons were dedicated to the production of tyrosine hydroxylase, the first enzyme in the biosynthetic pathway for the synthesis of dopamine, from which both norepinephrine and epinephrine are made.
This discovery is significant because it offers a reason for why schizophrenia patients have altered catecholamine neurotransmitter levels: They are preprogrammed to have more of the neurons that make these neurotransmitters.
“All behavior has a neurochemical basis in the brain,” Hook said. “This study shows that it is possible to look at precise chemical changes in neurons of people with schizophrenia.”
The applications for future treatments include being able to evaluate the severity of an individual’s disease, identify different sub-types of the disease and pre-screen patients for drugs that would be most likely to help them. It also offers a way to test the efficacy of new drugs.
“It is very powerful to be able to see differences in neurons derived from individual patients and a big accomplishment in the field to develop a method that allows this,” Hook said.
Pictured: Enzymes that biosynthesize the neurotransmitters dopamine (left), norepinephrine (center) and epinephrine (right).
high resolution →

ucsdhealthsciences:

Scientists Discover Neurochemical Imbalance in Schizophrenia

Using human induced pluripotent stem cells (hiPSCs), researchers at Skaggs School of Pharmacy and Pharmaceutical Sciences at University of California, San Diego have discovered that neurons from patients with schizophrenia secrete higher amounts of three neurotransmitters broadly implicated in a range of psychiatric disorders.

The findings, reported online Sept. 11 in Stem Cell Reports, represent an important step toward understanding the chemical basis for schizophrenia, a chronic, severe and disabling brain disorder that affects an estimated one in 100 persons at some point in their lives. Currently, schizophrenia has no known definitive cause or cure and leaves no tell-tale physical marks in brain tissue.

"The study provides new insights into neurotransmitter mechanisms in schizophrenia that can lead to new drug targets and therapeutics,” said senior author Vivian Hook, PhD, a professor with Skaggs School of Pharmacy and UC San Diego School of Medicine.

In the study, UC San Diego researchers with colleagues at The Salk Institute for Biological Studies and the Icahn School of Medicine at Mount Sinai, N.Y., created functioning neurons derived from hiPSCs, themselves reprogrammed from skin cells of schizophrenia patients. The approach allowed scientists to observe and stimulate human neurons in ways impossible in animal models or human subjects.

Researchers activated these neurons so that they would secrete neurotransmitters – chemicals that excite or inhibit the transmission of electrical signals through the brain. The process was replicated on stem cell lines from healthy adults.

A comparison of neurotransmitters produced by the cultured “brain in a dish” neurons showed that the neurons derived from schizophrenia patients secreted significantly greater amounts of the catecholamine neurotransmitters dopamine, norepinephrine and epinephrine.

Catecholamine neurotransmitters are synthesized from the amino acid tyrosine and the regulation of these neurotransmitters is known to be altered in a variety of psychiatric diseases. Several psychotropic drugs selectively target the activity of these neurotransmitters in the brain.

In addition to documenting aberrant neurotransmitter secretion from neurons derived from patients with schizophrenia, researchers also observed that more neurons were dedicated to the production of tyrosine hydroxylase, the first enzyme in the biosynthetic pathway for the synthesis of dopamine, from which both norepinephrine and epinephrine are made.

This discovery is significant because it offers a reason for why schizophrenia patients have altered catecholamine neurotransmitter levels: They are preprogrammed to have more of the neurons that make these neurotransmitters.

“All behavior has a neurochemical basis in the brain,” Hook said. “This study shows that it is possible to look at precise chemical changes in neurons of people with schizophrenia.”

The applications for future treatments include being able to evaluate the severity of an individual’s disease, identify different sub-types of the disease and pre-screen patients for drugs that would be most likely to help them. It also offers a way to test the efficacy of new drugs.

“It is very powerful to be able to see differences in neurons derived from individual patients and a big accomplishment in the field to develop a method that allows this,” Hook said.

Pictured: Enzymes that biosynthesize the neurotransmitters dopamine (left), norepinephrine (center) and epinephrine (right).

distant-traveller:

Milky Way over Yellowstone

The Milky Way was not created by an evaporating lake. The colorful pool of water, about 10 meters across, is known as Silex Spring and is located in Yellowstone National Park in Wyoming,USA. Illuminated artificially, the colors are caused by layers of bacteria that grow in the hot spring. Steam rises off the spring, heated by a magma chamber deep underneath known as the Yellowstone hotspot. Unrelated and far in the distance, the central band of our Milky Way Galaxy arches high overhead, a band lit by billions of stars. The above picture is a 16-image panorama taken late last month. If the Yellowstone hotspot causes another supervolcanic eruption as it did 640,000 years ago, a large part of North America would be affected.

Image credit & copyright: Dave Lane
high resolution →

distant-traveller:

Milky Way over Yellowstone

The Milky Way was not created by an evaporating lake. The colorful pool of water, about 10 meters across, is known as Silex Spring and is located in Yellowstone National Park in Wyoming,USA. Illuminated artificially, the colors are caused by layers of bacteria that grow in the hot spring. Steam rises off the spring, heated by a magma chamber deep underneath known as the Yellowstone hotspot. Unrelated and far in the distance, the central band of our Milky Way Galaxy arches high overhead, a band lit by billions of stars. The above picture is a 16-image panorama taken late last month. If the Yellowstone hotspot causes another supervolcanic eruption as it did 640,000 years ago, a large part of North America would be affected.

Image credit & copyright: Dave Lane