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Anytime you don’t feel powerful, remember this:

Supergiant stars are beasts! Their life is a fight between gravity pushing in and heat pushing out. They fuse heavier and heavier elements in their core until they get to iron. They can’t fuse any more. Iron absorbs more energy than it returns, so gravity takes over. The star’s core collapses and the star dies in an explosive supernova that outshines its entire galaxy.

The heat of a supernova fuses new elements during the explosion, which are then spread out into space via the nebula remnant. Nebulae are the birthplaces of new stars and solar systems.

The iron in your blood came from one of the most powerful explosions in the universe.

Anytime You Don’t Feel Powerful, Remember This:

You have something in your blood that can kill stars and build solar systems.

Scientists print all-liquid 3-D structures

Reconfigurable material could be used for liquid electronics and chemical synthesis, among other applications

Scientists from the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a way to print 3-D structures composed entirely of liquids. Using a modified 3-D printer, they injected threads of water into silicone oil – sculpting tubes made of one liquid within another liquid.

They envision their all-liquid material could be used to construct liquid electronics that power flexible, stretchable devices. The scientists also foresee chemically tuning the tubes and flowing molecules through them, leading to new ways to separate molecules or precisely deliver nanoscale building blocks to under-construction compounds.

The researchers have printed threads of water between 10 microns and 1 millimeter in diameter, and in a variety of spiraling and branching shapes up to several meters in length. What’s more, the material can conform to its surroundings and repeatedly change shape.

“It’s a new class of material that can reconfigure itself, and it has the potential to be customized into liquid reaction vessels for many uses, from chemical synthesis to ion transport to catalysis,” said Tom Russell, a visiting faculty scientist in Berkeley Lab’s Materials Sciences Division. He developed the material with Joe Forth, a postdoctoral researcher in the Materials Sciences Division, as well as other scientists from Berkeley Lab and several other institutions. They report their research March 24 in the journal Advanced Materials.

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redplanet44

7 years ago

Researchers Find New DNA Structure in Living Human Cells

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Your daily selection of the latest science news!

According to Breaking Science News

A team of scientists from the Garvan Institute of Medical Research and the Universities of New South Wales and Sydney has identified a new DNA structure — called the intercalated motif (i-motif) — inside living human cells.

Deep inside the cells in our body lies our DNA. The information in the DNA code — all 6 billion A, C, G and T letters — provides precise instructions for how our bodies are built, and how they work.

The iconic ‘double helix’ shape of DNA has captured the public imagination since 1953, when James Watson and Francis Crick famously uncovered the structure of DNA.

However, it’s now known that short stretches of DNA can exist in other shapes, in the laboratory at least — and scientists suspect that these different shapes might play an important role in how and when the DNA code is ‘read.’

“When most of us think of DNA, we think of the double helix. This research reminds us that totally different DNA structures exist — and could well be important for our cells,” said co-lead author Dr. Daniel Christ, from the Kinghorn Centre for Clinical Genomics at the Garvan Institute of Medical Research and St Vincent’s Clinical School at the University of New South Wales.

“The i-motif is a four-stranded ‘knot’ of DNA,” added co-lead author Dr. Marcel Dinger, also from the Garvan Institute of Medical Research and the University of New South Wales.

“In the knot structure, C letters on the same strand of DNA bind to each other — so this is very different from a double helix, where ‘letters’ on opposite strands recognize each other, and where Cs bind to Gs [guanines].”

Although researchers have seen the i-motif before and have studied it in detail, it has only been witnessed in vitro — that is, under artificial conditions in the laboratory, and not inside cells. In fact, they have debated whether i-motif DNA structures would exist at all inside living things — a question that is resolved by the new findings.

To detect the i-motifs inside cells, Dr. Christ, Dr. Dinger and their colleagues developed a precise new tool — a fragment of an antibody molecule — that could specifically recognize and attach to i-motifs with a very high affinity.

Until now, the lack of an antibody that is specific for i-motifs has severely hampered the understanding of their role.

Crucially, the antibody fragment didn’t detect DNA in helical form, nor did it recognize ‘G-quadruplex structures’ (a structurally similar four-stranded DNA arrangement).

With the new tool, the team uncovered the location of ‘i-motifs’ in a range of human cell lines.

Using fluorescence techniques to pinpoint where the i-motifs were located, the study authors identified numerous spots of green within the nucleus, which indicate the position of i-motifs.

The scientists showed that i-motifs mostly form at a particular point in the cell’s ‘life cycle’ — the late G1 phase, when DNA is being actively ‘read.’

They also showed that i-motifs appear in some promoter regions — areas of DNA that control whether genes are switched on or off — and in telomeres, ‘end sections’ of chromosomes that are important in the aging process.

“We think the coming and going of the i-motifs is a clue to what they do. It seems likely that they are there to help switch genes on or off, and to affect whether a gene is actively read or not,” said study first author Dr. Mahdi Zeraati, also from the Garvan Institute of Medical Research and the University of New South Wales.

“We also think the transient nature of the i-motifs explains why they have been so very difficult to track down in cells until now,” Dr. Christ added.

“It’s exciting to uncover a whole new form of DNA in cells — and these findings will set the stage for a whole new push to understand what this new DNA shape is really for, and whether it will impact on health and disease,” Dr. Dinger said.

The team’s results appear in the journal Nature Chemistry.

Carrying and releasing nanoscale cargo with ‘nanowrappers’

This holiday season, scientists at the Center for Functional Nanomaterials (CFN) – a U.S. Department of Energy Office of Science User Facility at Brookhaven National Laboratory – have wrapped a box of a different kind. Using a one-step chemical synthesis method, they engineered hollow metallic nanosized boxes with cube-shaped pores at the corners and demonstrated how these “nanowrappers” can be used to carry and release DNA-coated nanoparticles in a controlled way. The research is reported in a paper published on Dec. 12 in ACS Central Science, a journal of the American Chemical Society (ACS).

“Imagine you have a box but you can only use the outside and not the inside,” said co-author Oleg Gang, leader of the CFN Soft and Bio Nanomaterials Group. “This is how we’ve been dealing with nanoparticles. Most nanoparticle assembly or synthesis methods produce solid nanostructures. We need methods to engineer the internal space of these structures.”

“Compared to their solid counterparts, hollow nanostructures have different optical and chemical properties that we would like to use for biomedical, sensing, and catalytic applications,” added corresponding author Fang Lu, a scientist in Gang’s group. “In addition, we can introduce surface openings in the hollow structures where materials such as drugs, biological molecules, and even nanoparticles can enter and exit, depending on the surrounding environment.”

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redplanet44

7 years ago

Organic Pigment Photocapacitors May Restore Sight to Blind People

A simple retinal prosthesis is being developed in collaboration between Tel Aviv University in Israel and LiU. Fabricated using cheap and widely-available organic pigments used in printing inks and cosmetics, it consists of tiny pixels like a digital camera sensor on a nanometric scale. Researchers hope that it can restore sight to blind people.

Researchers led by Eric Glowacki, principal investigator of the organic nanocrystals subgroup in the Laboratory of Organic Electronics, Linköping University, have developed a tiny, simple photoactive film that converts light impulses into electrical signals. These signals in turn stimulate neurons (nerve cells). The research group has chosen to focus on a particularly pressing application, artificial retinas that may in the future restore sight to blind people. The Swedish team, specializing in nanomaterials and electronic devices, worked together with researchers in Israel, Italy and Austria to optimise the technology. Experiments in vision restoration were carried out by the group of Yael Hanein at Tel Aviv University in Israel. Yael Hanein’s group is a world-leader in the interface between electronics and the nervous system.

The results have recently been published in the prestigious scientific journal Advanced Materials.

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redplanet44

7 years ago

Solar System 10 Things to Know: Planetary Atmospheres

Every time you take a breath of fresh air, it’s easy to forget you can safely do so because of Earth’s atmosphere. Life on Earth could not exist without that protective cover that keeps us warm, allows us to breathe and protects us from harmful radiation—among other things.

What makes Earth’s atmosphere special, and how do other planets’ atmospheres compare? Here are 10 tidbits:

1. On Earth, we live in the troposphere, the closest atmospheric layer to Earth’s surface. “Tropos” means “change,” and the name reflects our constantly changing weather and mixture of gases.

Solar System 10 Things To Know: Planetary Atmospheres

It’s 5 to 9 miles (8 to 14 kilometers) thick, depending on where you are on Earth, and it’s the densest layer of atmosphere. When we breathe, we’re taking in an air mixture of about 78 percent nitrogen, 21 percent oxygen and 1 percent argon, water vapor and carbon dioxide. More on Earth’s atmosphere›

2. Mars has a very thin atmosphere, nearly all carbon dioxide. Because of the Red Planet’s low atmospheric pressure, and with little methane or water vapor to reinforce the weak greenhouse effect (warming that results when the atmosphere traps heat radiating from the planet toward space), Mars’ surface remains quite cold, the average surface temperature being about -82 degrees Fahrenheit (minus 63 degrees Celsius). More on the greenhouse effect›

3. Venus’ atmosphere, like Mars’, is nearly all carbon dioxide. However, Venus has about 154,000 times more carbon dioxide in its atmosphere than Earth (and about 19,000 times more than Mars does), producing a runaway greenhouse effect and a surface temperature hot enough to melt lead. A runaway greenhouse effect is when a planet’s atmosphere and surface temperature keep increasing until the surface gets so hot that its oceans boil away. More on the greenhouse effect›

4. Jupiter likely has three distinct cloud layers (composed of ammonia, ammonium hydrosulfide and water) in its “skies” that, taken together, span an altitude range of about 44 miles (71 kilometers). The planet’s fast rotation—spinning once every 10 hours—creates strong jet streams, separating its clouds into dark belts and bright zones wrapping around the circumference of the planet. More on Jupiter›

5. Saturn’s atmosphere—where our Cassini spacecraft ended its 13 extraordinary years of exploration of the planet—has a few unusual features. Its winds are among the fastest in the solar system, reaching speeds of 1,118 miles (1,800 kilometers) per hour. Saturn may be the only planet in our solar system with a warm polar vortex (a mass of swirling atmospheric gas around the pole) at both the North and South poles. Also, the vortices have “eye-wall clouds,” making them hurricane-like systems like those on Earth.

Another uniquely striking feature is a hexagon-shaped jet streamencircling the North Pole. In addition, about every 20 to 30 Earth years, Saturn hosts a megastorm (a great storm that can last many months). More on Saturn›

6. Uranus gets its signature blue-green color from the cold methane gas in its atmosphere and a lack of high clouds. The planet’s minimum troposphere temperature is 49 Kelvin (minus 224.2 degrees Celsius), making it even colder than Neptune in some places. Its winds move backward at the equator, blowing against the planet’s rotation. Closer to the poles, winds shift forward and flow with the planet’s rotation. More on Uranus›

7. Neptune is the windiest planet in our solar system. Despite its great distance and low energy input from the Sun, wind speeds at Neptune surpass 1,200 miles per hour (2,000 kilometers per hour), making them three times stronger than Jupiter’s and nine times stronger than Earth’s. Even Earth’s most powerful winds hit only about 250 miles per hour (400 kilometers per hour). Also, Neptune’s atmosphere is blue for the very same reasons as Uranus’ atmosphere. More on Neptune›

8. WASP-39b, a hot, bloated, Saturn-like exoplanet (planet outside of our solar system) some 700 light-years away, apparently has a lot of water in its atmosphere. In fact, scientists estimate that it has about three times as much water as Saturn does. More on this exoplanet›

9. A weather forecast on “hot Jupiters”—blistering, Jupiter-like exoplanets that orbit very close to their stars—might mention cloudy nights and sunny days, with highs of 2,400 degrees Fahrenheit (about 1,300 degrees Celsius, or 1,600 Kelvin). Their cloud composition depends on their temperature, and studies suggest that the clouds are unevenly distributed. More on these exoplanets›

10. 55 Cancri e, a “super Earth” exoplanet (a planet outside of our solar system with a diameter between Earth’s and Neptune’s) that may be covered in lava, likely has an atmosphere containing nitrogen, water and even oxygen–molecules found in our atmosphere–but with much higher temperatures throughout. Orbiting so close to its host star, the planet could not maintain liquid water and likely would not be able to support life. More on this exoplanet›

Read the full version of this week’s Solar System 10 Things to Know HERE.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

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redplanet44

7 years ago

Scientists make research ‘jelly’ grow more like biological tissues

Opens up new possibilities in tissue engineering and soft robotics

Scientists from Nanyang Technological University, Singapore (NTU Singapore) and Carnegie Mellon University (CMU) have found a way to direct the growth of hydrogel, a jelly-like substance, to mimic plant or animal tissue structure and shapes.

The team’s findings, published in Proceedings of the National Academy of Sciences today, suggest new applications in areas such as tissue engineering and soft robotics where hydrogel is commonly used. The team has also filed a patent at CMU and NTU.

In nature, plant or animal tissues are formed as new biomass is added to existing structures. Their shape is the result of different parts of those tissues growing at different rates.

Mimicking this behaviour of biological tissues in nature, the research team comprising CMU scientists Changjin Huang, David Quinn, K. Jimmy Hsia and NTU President-designate Prof Subra Suresh, showed that through manipulation of oxygen concentration, one can pattern and control the growth rate of hydrogels to create the desired complex 3D shapes.

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redplanet44

7 years ago

Radioactive Diamond Batteries: Making Good Use Of Nuclear Waste

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redplanet44

6 years ago

Gene discovery unlocks mysteries to our immunity

"It's exciting to consider that C6 has existed for more than 500 million years, preserved and passed down from simple organisms all the way to humans. But only now are we gaining insights into its importance."

Australia’s national science agency CSIRO has identified a new gene that plays a critical role in regulating the body’s immune response to infection and disease.

The discovery could lead to the development of new treatments for influenza, arthritis and even cancer.

The gene, called C6orf106 or “C6”, controls the production of proteins involved in infectious diseases, cancer and diabetes. The gene has existed for 500 million years, but its potential is only now understood.

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