Once again the time is here. Science talk has arrived. New discoveries, new takes on old knowledge, and other bits of news are all available for the perusing in today's information world. Over the fold are selections from the past week from a few of the many excellent science news sites around the world. Today's tidbits include why carbon nanotubes spell trouble for cells, deep oceans may mask global warming for decade-long periods, turning back the clock on adult stem cells, citizen scientists may join the search for earth-like planets, researchers have developed a new type of antimagnet, archeologists uncover evidence of an ancient shipyard near Rome, and a carnivorous plant inspires a new coating that resists just about any liquid. Pull up that comfy chair and bask in the sunshine. There is plenty of room for everyone. Get ready for another session of Dr. Possum's science education and entertainment.
Featured Stories
As the uses of carbon nanotubes expand in our world the concerns continue to rise at the same time.
Like asbestos fibers, commercially available carbon nanotubes and gold nanowires have rounded tips that often range from 10 to 100 nanometers in diameter. Size is important here; the diameter fits well within the cell’s parameters for what it can handle. Brushing up against the nanotube, special proteins called receptors on the cell spring into action, clustering and bending the membrane wall to wrap the cell around the nanotube tip in a sequence that the authors call “tip recognition.” As this occurs, the nanotube is tipped to a 90-degree angle, which reduces the amount of energy needed for the cell to engulf the particle.
Once the engulfing — endocytosis — begins, there is no turning back. Within minutes, the cell senses it can’t fully engulf the nanostructure and essentially dials 911. “At this stage, it’s too late,” (researcher) Gao said. “It’s in trouble and calls for help, triggering an immune response that can cause repeated inflammation
According to a new analysis the world's deep oceans may absorb enough heat to mask global warming for long periods of time.
The simulations, which were based on projections of future greenhouse gas emissions from human activities, indicated that temperatures would rise by several degrees during this century. But each simulation also showed periods in which temperatures would stabilize for about a decade before climbing again. For example, one simulation showed the global average rising by about 2.5 degrees Fahrenheit (1.4 degrees Celsius) between 2000 and 2100, but with two decade-long hiatus periods during the century.
During these hiatus periods, simulations showed that extra energy entered the oceans, with deeper layers absorbing a disproportionate amount of heat due to changes in oceanic circulation. The vast area of ocean below about 1,000 feet (300 meters) warmed by 18% to 19% more during hiatus periods than at other times. In contrast, the shallower global ocean above 1,000 feet warmed by 60% less than during non-hiatus periods in the simulation.
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The simulations also indicated that the oceanic warming during hiatus periods has a regional signature. During a hiatus, average sea-surface temperatures decrease across the tropical Pacific, while they tend to increase at higher latitudes, especially around 30°S and 30°N in the Pacific and between 35°N and 40°N in the Atlantic, where surface waters converge to push heat into deeper oceanic layers.
These patterns are similar to those observed during a La Niña event, according to (researcher) Meehl. He adds that El Niño and La Niña events can be overlaid on top of a hiatus-related pattern. Global temperatures tend to drop slightly during La Niña, as cooler waters reach the surface of the tropical Pacific, and they rise slightly during El Niño, when those waters are warmer.
The excitement that is today's stem cell research continues again this week with an announcement about adult stem cells.
Adult stem cells are important because they help keep human tissues healthy by replacing cells that have gotten old or damaged. They’re also multipotent, which means that an adult stem cell can grow and replace any number of body cells in the tissue or organ they belong to. However, just as the cells in the liver, or any other organ, can get damaged over time, adult stem cells undergo age-related damage. And when this happens, the body can’t replace damaged tissue as well as it once could, leading to a host of diseases and conditions. But if scientists can find a way to keep these adult stem cells young, they could possibly use these cells to repair damaged heart tissue after a heart attack; heal wounds; correct metabolic syndromes; produce insulin for patients with type 1 diabetes; cure arthritis and osteoporosis and regenerate bone.
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“By suppressing the accumulation of toxic transcripts from retrotransposons, we were able to reverse the process of human adult stem cell aging in culture,” said (researcher) Lunyak.
“Furthermore, by rewinding the cellular clock in this way, we were not only able to rejuvenate ’aged’ human stem cells, but to our surprise we were able to reset them to an earlier developmental stage, by up-regulating the “pluripotency factors” – the proteins that are critically involved in the self-renewal of undifferentiated embryonic stem cells.” she said.
In December anyone with a strong interest in astronomy may join Planet Hunters and help find earth-like planets in the universe.
Because of the huge amount of data being made available by Kepler, astronomers rely on computers to help them sort through the data and search for possible planet candidates. “But computers are only good at finding what they’ve been taught to look for,” said Meg Schwamb, another Yale astronomer and Planet Hunters co-founder. “Whereas the human brain has the uncanny ability to recognize patterns and immediately pick out what is strange or unique, far beyond what we can teach machines to do.”
After the success of the Galaxy Zoo project, the Yale team decided to enlist web users once again to create what they hope will become a global network of human computing power.
When users log on to the Planet Hunters website, they’ll be asked to answer a series of simple questions about one of the stars’ light curves—a graph displaying the amount of light emitted by the star over time—to help the Yale astronomers determine whether it displays a repetitive dimming of light, identifying it as an exoplanet candidate.
Researchers have designed a new type of magnetic cloak which shields objects from external magnetic fields and prevents magnetic internal fields from leaking outside.
The development of such a device, described as an ‘antimagnet’, could offer many beneficial applications, such as protecting a ship’s hull from mines designed to detonate when a magnetic field is detected, or allowing patients with pacemakers or cochlear implants to use medical equipment.
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Take, for example, a patient with a pacemaker undergoing an MRI scan. If an MRI’s large magnetic field interacts with the pacemaker, it can cause serious damage to both the device and the patient. The metal in the pacemaker could also interact with and distort the MRI’s large magnetic field, affecting the machine’s detection capabilities.
The researchers, from Universitat Autònoma de Barcelona, are aware that the technology could also be used by criminals to dodge security systems, for example in airports and shops, but they are confident that the new research could benefit society in a positive way, while the risks could be minimized by informing security officials about potential devices, enabling them to anticipate and neutralize problems.
Excavation of Portus, the ancient Roman port, has uncovered what archeologists believe is an ancient shipyard.
It has long been known that Portus was a crucial trade gateway linking Rome to the Mediterranean throughout the Imperial period and the Portus Project1 team has been investigating the port’s significance over a number of years. Until now, no major shipyard building for Rome has been identified, apart from the possibility of one on the Tiber near Monte Testaccio, and a smaller one recently claimed for the neighbouring river port at Ostia.
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The huge building the team has discovered dates from the 2nd century AD and would have stood c. 145 metres long and 60 metres wide – an area larger than a football pitch. In places, its roof was up to 15 metres high, or more than three times the height of a double-decker bus. Large brick-faced concrete piers or pillars, some three metres wide and still visible in part, supported at least eight parallel bays with wooden roofs.
The wet surface of the cup of a pitcher plant becomes nearly frictionless so insects slide to their demise as plant food.
Adopting the plant’s slick strategy, a group of applied scientists at Harvard have created a material that repels just about any type of liquid, including blood and oil, and does so even under harsh conditions like high pressure and freezing temperatures.
The bio-inspired liquid repellence technology...should find applications in biomedical fluid handling, fuel transport, and anti-fouling and anti-icing technologies. It could even lead to self-cleaning windows and improved optical devices.
Other Worthy Stories of the Week
How should we make hard decisions?
Vesta, an asteroid full of surprises
Astronomers confirm first planet orbiting two stars
CT study of early humans reveals evolutionary relationships
More than a sign of sleepiness, yawning may cool the brain
What's inside: Red wine
Equation: The law of rainbows
Black hole jets gone wild
Gamma ray bursts shed light on the nature of dark energy
Continents influenced human migration and the spread of technology
Researchers develop new technique for filling gaps in fossil record
Understanding methane's seabed escape
Fast switching and printable transistor invented
Climate fluctuations drove key events in human evolution
Sex life of the deep sea squid
New technique uses genomes to examine human migrations
Living in the galactic danger zone
Nature offers lessons on harvesting solar energy
For even more science news:
General Science Collectors:
Alpha-Galileo
BBC News Science and Environment
Eureka Science News
LiveScience
New Scientist
PhysOrg.com
SciDev.net
Science/AAAS
Science Alert
Science Centric
Science Daily
Scientific American
Space Daily
Blogs:
A Few Things Ill Considered Techie and Science News
Cantauri Dreams space exploration
Coctail Party Physics Physics with a twist.
Deep Sea News marine biology
Laelaps more vertebrate paleontology
List of Geoscience Blogs
ScienceBlogs
Space Review
Techonology Review
Tetrapod Zoologyvertebrate paleontology
Science Insider
Scientific Blogging.
Space.com
Wired News
Science RSS Feed: Medworm
The Skeptics Guide to the Universe--a combination of hard science and debunking crap
At Daily Kos:
This Week in Science by DarkSyde
Overnight News Digest:Science Saturday by Neon Vincent. OND tech Thursday by rfall.
Pique the Geek by Translator Sunday evenings about 9 Eastern time
All diaries with the DK GreenRoots Tag.
All diaries with the eKos Tag
A More Ancient World by matching mole
Astro Kos
SciTech at Dkos.
Sunday Science Videos by palantir
NASA picture of the day. For more see the NASA image gallery or the Astronomy Picture of the Day Archive
A quintet of Saturn's moons as seen from Cassini spacecraft, NASA, Public Domain