Show Notes:

Coma patient auditory function

• New research suggests a coma patient’s chances of surviving and waking up could be predicted by changes in the brain’s ability to discriminate sounds
• The low down
• Recovery from comas has been linked to auditory function before, but it wasn’t clear whether function depended on the time of assessment
• Previous studies tested patients several days or weeks after comas set in, in this new study looks at the critical phase during the first 48 hours
• At early stages, comatose brains can still distinguish between different sound patterns
• This ability progresses over time can predict whether a coma patient will survive and ultimately awaken which is very promising tool for prognosis
• Significance
• The study was led by neuroscientist of the University of Lausanne in Switzerland who studied 30 coma patients who had experienced heart attacks that deprived their brains of oxygen
• All the patients underwent therapeutic hypothermia, a standard treatment to minimize brain damage, in which their bodies were cooled to 33* Celsius for 24 hours
• They then played sounds for the patients and recorded their brain activity using scalp electrodes
• Once in hypothermic conditions during the first 24 hours of coma then again a day later at normal body temperature
• The sounds were a series of pure tones interspersed with sounds of different pitch, duration or location
• The brain signals revealed how well patients could discriminate the sounds, compared with five healthy subjects
• All the patients whose discrimination improved by the second day of testing survived and awoke from their comas
• Many of those whose sound discrimination deteriorated by the second day did not survive
• These results suggests that residual auditory function itself does not predict recovery, rather it’s the progression of function over time that is predictive.
• The study couldn’t distinguish whether auditory function initially was preserved due to the hypothermia treatment or was related merely to the early stage of coma
• Scientists speculate that distracting neural jabber may have been reduced during the hypothermia, making it easier for the patients’ brains to separate sounds
• Of Note
• Scientists are now running a follow-up study with 120 coma patients and whether the results can be replicated in a bigger population
• The tests could eventually give information about patients who will survive during the first two days of coma
• Further Reading / In the News
• Auditory test predicts coma awakening | Body & Brain | Science News

— NEWS BYTE —

Water on Mercury?!

• The low down
• There has been speculation about water ice on Mercury dates back more than 20 years
• In 1991, Earth-bound astronomers fired radar signals to Mercury and received results showing there could be ice at both poles
• The speculations were reinforced by 1999 measurements using the more powerful Arecibo Observatory microwave beam in Puerto Rico
• Radar pictures beamed back to New Mexico’s Very Large Array showed white areas that researchers suspected was water ice.
• Temperatures on Mercury can reach 800 F [427 C] around the north pole, in areas permanently shielded from the sun’s heat
• Significance
• Confirming decades of suspicion, a NASA spacecraft has spotted vast deposits of water ice on the planet closest to the sun
• Although the laser is weak, about the strength of a flashlight, but just powerful enough to distinguish bright icy areas from the darker, surrounding Mercury regolith
• Messenger’s neutron spectrometer spotted hydrogen, which is a large component of water ice. But the temperature profile unexpectedly showed that dark, volatile materials – consistent with climes in which organics survive – are mixing in with the ice
• Organic materials are life’s ingredients, though they do not necessarily lead to life itself the presence of organics is also suspected on airless, distant worlds such as Pluto
• Messenger spacecraft found a mix of frozen water and possible organic materials
• There is evidence of big pockets of ice is visible from a latitude of 85 degrees north up to the pole and smaller deposits scattered as far away as 65 degrees north.
• Researchers also believe the south pole has ice, but Messenger’s orbit has not allowed them to obtain extensive measurements of that region yet
• Of Note
• Is is suspected that Mercury’s water ice is coated with a 4-inch (10 centimeters) blanket of “thermally insulating material
• In the near future NASA will direct Messenger’s observation toward that area in the coming months — when the angle of the sun allows — to get a better look
• Messenger will spiral closer to the planet in 2014 and 2015 as it runs out of fuel
• Multimedia
• YouTube | MESSENGER Confirms Water Ice in Abundance at Mercury’s Poles | NASAtelevision
• Further Reading / In the News
• MESSENGER finds new evidence for water ice, organic material at Mercury’s poles | phys.org
• Water Ice Found at Mercury’s North Pole | Space.com

Subglacial Life

• In one of the most remote lakes of Antarctica, nearly 65 feet beneath the icy surface, scientists have uncovered a community of bacteria
• Last time on SciByte
• SciByte 33 | Sub Glacial Lakes & Updates [February 14, 2012]
• The low down
• Lake Vida, the largest of several unique lakes found in the McMurdo Dry Valleys, contains no oxygen, is mostly frozen and possesses the highest nitrous oxide levels of any natural water body on Earth
• At approximately six times saltier than seawater the average temperature is minus 8 degrees Fahrenheit
• The brine harbors a surprisingly diverse and abundant variety of bacteria that survive without a current source of energy from the sun
• Previous studies of Lake Vida dating back to 1996 indicate the brine and its inhabitants have been isolated from outside influences for more than 3,000 years.
• Significance
• Collaborators developed stringent protocols and specialized equipment for their 2005 and 2010 field campaigns to sample from the lake brine while avoiding contaminating the pristine ecosystem
• To sample unique environments such as this, researchers must work under secure, sterile tents on the lake’s
  surface
• The tents kept the site and equipment clean as researchers drilled ice cores, collected samples of the salty brine residing in the lake ice and assessed the chemical qualities of the water and its potential for harboring and sustaining life
• Analyses suggest chemical reactions between the brine and the underlying iron-rich sediments generate nitrous oxide and molecular hydrogen which may provide the energy needed to support the brine’s diverse microbial life.
• Additional research is underway to analyze the abiotic, chemical interactions between the Lake Vida brine and its sediment
• Of Note
• This finding expands our knowledge of environmental limits for life and how life can sustain itself in these extreme environments, it also helps define new niches of habitability
• The best analog we have for possible ecosystems in the subsurface waters of Saturn’s moon Enceladus and Jupiter’s moon Europa
• Further investigation of the microbial community by using different genome sequencing approaches
• Further Reading / In the News
• Ancient Microbes Found Living Beneath the Icy Surface of Antarctic Lake | dri.edu
• NASA – NASA Researchers Discover Ancient Microbes in Antarctic Lake | NASA.gov

— TWO-BYTE NEWS —

60-day Bread?!

• The low down
• Using microwave technology, one company says it can make bread last for two months
• The claim
• The claim is that it can preserve at least some of our food for longer, by zapping it with microwaves, with nuked bread can last up to 60 days
• The equipment, which looks like a CT scanner for food, was originally developed to kill organisms like multi-resistant staph bacteria and salmonella
• The developers realized it also kills bread mold in about a 10-second zap.
• It works much like a home microwave, but the waves are produced in various frequencies, which allows for uniform heating
• The same technology could also preserve fresh food like poultry, produce and more
• Of Note
• This technology is far more complex that microwaves that are commercially accessible.
• Do not assume “nuking” you food in the microwave at home with make your bread last longer
• Further Reading / In the News
• Mmmmm? Scientists Make Bread Last 60 Days | Popular Science
• MicroZap

– SPACECRAFT UPDATE –

Voyager 1, inch by inch

• The low down
• Data from two onboard instruments that measure charged particles showed the spacecraft first entered this magnetic highway region on July 28, 2012
• Scientists refer to this new region as a magnetic highway for charged particles because our sun’s magnetic field lines are connected to interstellar magnetic field lines
• They infer that this region is still inside our solar bubble because the direction of the magnetic field lines has not changed
• The magnetic region is unlike it has been in before—about 10 times more intense than before the termination shock—but the magnetic field data show no indication we’re in interstellar space
• The magnetic field data has turned out to be the key to pinpointing when Voyager 1 crossed the termination shock.
• Multimedia
• YouTube | Voyager’s Ride on the Magnetic Highway | JPLnews
• Social Media
• NASA Voyager @NASAVoyager
• Further Reading / In the News
• Voyager 1 encounters new region in deep space, NASA says | phys.org

– CURIOSITY UPDATE –

• Mission Notes
• After several weeks of being stationary at the Rocknest site Curiosity began driving again on Sol 100
• A significant milestone on the mission has now reached about a 0.3mi [0.5km] of total driving distance on the surface of Mars
• The Curiosity team is now going to be moving to the East to a place called Point Lake while looking for a target to perform our first ever drill on Mars
• Surface Radiation Levels
• Average yearly dosage on Earth is .004 Sievert, Head CT scan is 0.002 Sv and a chest CT scan is 0.007 Sv
• Astronauts aboard the International Space Station experience an average daily dose between 0.4 and 1.0 millisieverts
• On it’s way to Mars its radiation data was around 1.9 millisieverts per day during the flight
• Astronauts on the surface on Mars would receive an average dose of about 0.7 millisieverts per day
• A mission consisting of a 180-day outbound cruise, a 600-day stay on Mars and another 180-day flight back to Earth would expose an astronaut to a total radiation dose of about 1.1 sieverts, unit of radiation
• While 1 Sievert is 100 rem and I’ve seen numbers for CT scan from 0.01–0.06 sievert the ESA caps an astronauts lifetime exposure to 1 sievert
• 1.1 Sv ~ 275 years on Earth ~ 4.8 years on the Space Station
• Radiation Dose Chart | xkcd.com
• My Hypotheses from Last Week
• Surface Radiation Levels
• Chace for organic compounds, most likely a simple hydrocarbon
• Much less likely chance would be the announcement of nitrogen
• The “de-Hype”
• While many people had assumed that Curiosity had detected organic compounds in the Martian soil later statements said that’s it was not the case
• Statements made mid to later last week stated that at this point in the mission, the instruments on the rover have not detected any definitive evidence of Martian organics
• Announcement
• No final results have yet been released on the surface radiation levels
• Water and sulfur and chlorine-containing substances, among other ingredients, showed up in samples Curiosity’s arm delivered to an analytical laboratory inside the rover
• There is still no definitive detection of Martian organics at this point
• SAM tentatively identified the oxygen and chlorine compound perchlorate
• Perclorate is a reactive chemical previously found in arctic Martian soil by NASA’s Phoenix Lander
• Perchlorates are the salts derived from perchloric acid and most are soluble in water
• Natural perchlorate on Earth is in arid environments possibly from the oxidation of chlorine species involving ozone or its photochemical products
• Reactions with other chemicals heated in SAM formed chlorinated methane compounds, one-carbon organics that were detected by the instrument
• The chlorine is of Martian origin, but it is possible the carbon may be of Earth origin, carried by Curiosity and detected by SAM’s high sensitivity design
• Analysis
• While they are going to announce the final data for surface radiation levels that was not THE BIG announcement as I had thought
• While the chlorine is of Martian origin, it is possible the carbon may be of Earth origin, carried by Curiosity and detected by SAM’s high sensitivity design
• Multimedia
• YouTube | Curiosity Rover Report (Nov. 29, 2012): Curiosity Roves Again
• Image Galleries at JPL and Curiosity Mulimedia
• New Rover?
• Rumors about a 2020 mission leaking out
• Social Media
• Curiosity Rover @MarsCuriosity
• Further Reading / In the News
• Curiosity rover: No big surprise in first soil test | phys.org
• NASA – Curiosity Roves Again | NASA.gov
• Everybody Chill, NASA Says: No Martian Organics Found | UniverseToday.com
• Radiation Dose Chart | xkcd.com
• Astronauts Could Survive Mars Radiation for Long Stretches, Rover Study Suggests | Space.com
• No Huge Discovery by Mars Rover Curiosity Yet | Space.com

SCIENCE CALENDAR

Looking back

• Dec 11 1790 : 222 years ago : Aurora Borealis : the first recorded sighting of the Aurora Borealis took place in New England. The report said that a mysterious face seemed to appear in the atmosphere. It caused considerable alarm, as being regarded by many as a precursor of the last judgment. Most aurora borealis displays occur in September and October and again in March and April. The green, red, and frost-white light displays occur most frequently when there is a great deal of sunspot activity. “This evening, about eight o’clock there arose a bright and red light in the E.N.E. like the light which arises from a house on fire … which soon spread itself through the heavens from east to west, reaching about 43 or 44 degrees in height, and was equally broad.”

Looking up this week

• Keep an eye out for …
• Thurs, Dec 6 | Middle of the night | The last-quarter Moon rises moving to the Eastern sky by morning
• Mercury, Venus, and Saturn | SE at Dawn | They form a diagonal line with Venus by far the brightest, with Saturn to the upper right and Mercury to the lower left.
• Mars | Twilight | Low in the SW sky
• Jupiter | Sunset to Sunrise | Rises in the E, moving to higher in the Southern sky around midnight and setting in the West around sunrise. This is because it is at opposition on Dec 2–3
• Further Reading and Resources
• Sky&Telescope
• SpaceWeather.com
• StarDate.org
• For the Southern hemisphere: SpaceInfo.com.au
• Constellations of the Southern Hemisphere : astronomyonline.org
• Royal Astronomical Society of New Zealand : rasnz.org.nz
• AstronomyNow
• HeavensAbove