We take a look at more Alzheimer\’s breakthroughs, nuclear fusion to Mars, finding an old Soviet mars probe, a comet aiming for Mars, glasses that read to you, viewer feedback, Curiosity news, and as always take a peek back into history and up in the sky this week.
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Show Notes:
Show Notes:
Mysteries of Alzheimer\’s Disease
- New findings show that brain damage in Alzheimer\’s disease is linked to the overactivation of an enzyme called AMPK
- In addition findings suggest the need for further safety studies on an existing drug, metformin, a popular treatment for Type 2 Diabetes, causes AMPK activation.
- What We Know
- Researchers have known for years that people in the earliest stages of Alzheimer\’s disease begin to lose synapses in certain memory-related brain areas
- Small aggregates of the protein amyloid beta can cause this, but how they do so has been a mystery
- Recent Research
- Until recently, Polleux\’s laboratory has been focused not on Alzheimer\’s research but on the normal development and growth of neurons
- In 2011 they reported that AMPK overactivation by metformin, among other compounds, in animal models impaired the ability of neurons to grow output stalks, or axons
- Around the same time, separate research groups found clues that AMPK might also have a role in Alzheimer\’s disease
- One team used J20 mice, which are genetically engineered to overproduce mutant amyloid beta
- When they blocked the activity of CAMKK2 or AMPK in those neurons, they completely prevented the spine loss
- Recent studies have shown that amyloid beta\’s toxicity to dendritic spines (rootlike, synapse-bearing input stalks that receive signals from other neurons) depends largely on the presence of tau, but just how the two Alzheimer\’s proteins interact has been unclear
- Tangles of tau with multiple phosphorylations, altered function and activity, are known to accumulate in neurons in affected brain areas in Alzheimer
- Amyloid beta oligomers can\’t cause dendritic spine loss unless AMPK overactivation occurs-and indeed AMPK overactivation on its own can cause the spine loss
- To determine whether the reported interactions of AMPK with amyloid beta and tau can in fact cause the damage seen in the brains of Alzheimer\’s patients, a postdoctoral research associate began by confirming that amyloid beta, in the small-aggregate (\”oligomer\”) form that is toxic to synapses, does indeed strongly activate AMPK
- Domino Effect of Biology
- Amyloid beta oligomers stimulate certain neuronal receptors, which in turn causes an influx of calcium ions into the neurons
- This calcium influx triggers the activation of an enzyme called CAMKK2, which appears to be the main activator of AMPK in neurons
- Then AMPK overactivation in neurons is the essential reason for amyloid beta\’s synapse-harming effect
- Still to Come
- Colleagues are now following up with further experiments to determine what other toxic processes, such as excessive autophagy, mechanism that involves cell degeneration or dysfunction, are promoted by AMPK overactivation and might also contribute to the long-term aspects of Alzheimer\’s disease progression
- Scientists are also interested in the long-term effects of blocking AMPK overactivation in the J20 mouse model as well as in other mouse models of Alzheimer\’s disease, which normally develop cognitive deficits at later stages
- The pharmaceuticals industry is now potentially interested in targeting either CAMKK2 or AMPK
- Multimedia
- YouTube Clip | Neuron Communication with Dendritic Spines
- YouTube Clip | Tau tangles
- YouTube | Inside the Brain: Unraveling the Mystery of Alzheimer\’s Disease [HQ] | AlzheimerUniversal
- Further Reading / In the News
- Study unravels central mystery of Alzheimer\’s disease | MedicalXpress
— NEWS BYTE —
Quick Trip to Mars
- Viewer Feedback | Check This Out!
- Akito
- The Premise
- Previous estimates have found that a roundtrip manned mission to Mars would require about 500 days of space travel
- A team of scientists have published papers calculating the potential for 30- and 90-day expeditions to Mars using a rocket powered by fusion, which would make the trip more practical and less costly
- Nuclear fusion
- Nuclear fusion occurs when the nuclei of two or more atoms combine, resulting in a release of energy
- The sun and other stars convert this energy into light, and the same process gives hydrogen bombs their destructive power
- The Project
- Funded through NASA\’s Innovative Advanced Concepts Program, it is one of a handful of projects awarded a second round of funding last fall after already receiving phase-one money in a field of 15 projects chosen from more than 700 proposals
- Last month the team presented their mission analysis for a trip to Mars, along with detailed computer modeling and initial experimental results
- They have demonstrated successful lab tests of all portions of the process
- Now, the key will be combining each isolated test into a final experiment that produces fusion using this technology
- Researchers and scientists are now building components of a fusion-powered rocket aimed to clear many of the hurdles that block deep space travel, including long times in transit, exorbitant costs and health risks
- Power
- To power the rocket, the team has devised a system in which a powerful magnetic field causes large metal rings to implode around this plasma, compressing it to a fusion state
- The converging rings merge to form a shell that ignites the fusion, but only for a few microseconds which is enough energy to quickly heat and ionize the shell
- This super-heated, ionized metal is ejected out of the rocket nozzle at a high velocity. This process is repeated every minute or so, propelling the spacecraft
- A small grain of sand of this material has the same energy content as 1 gallon of rocket fuel.
- Hardware
- The team had a sample of the collapsed, fist-sized aluminum ring resulting from one of those tests on hand for people to see and touch at the recent NASA symposium
- Now, the team is working to bring it all together by using the technology to compress the plasma and create nuclear fusion
- With the flip of a switch, the capacitors are simultaneously triggered to deliver 1 million amps of electricity for a fraction of a second to the magnet, which quickly compresses the metal ring.
- The mechanical process and equipment used are reasonably straightforward
- In actual space travel, scientists would use lithium metal as the crushing rings to power the rocket. Lithium is very reactive, and for lab-testing purposes, aluminum works just as well
- Concerns
- Nuclear fusion may draw concern because of its application in nuclear bombs, but its use in this scenario is very different
- The fusion energy for powering a rocket would be reduced by a factor of 1 billion from a hydrogen bomb, too little to create a significant explosion
- Also, concept uses a strong magnetic field to contain the fusion fuel and guide it safely away from the spacecraft and any passengers within
- Multimedia
- YouTube | The Fusion Driven Rocket: Animation | FusionDrivenRocket
- YouTube Channel | Fusion Driven Rocket
- Further Reading / In the News
- Nuclear Fusion Could Power Rocket to Mars | Space.com
- Rocket powered by nuclear fusion could send humans to Mars | Phys.org
Soviet Lander Found
- Viewer Feedback | Check This Out!
- Allan from TechSnap
- Soviet Mars 3 Mission
- On May 28, 1971, the Soviet Union launched the Mars 3 mission which consisted of an orbiter and lander destined for the Red Planet. Just over six months later on December 2, 1971, Mars 3 arrived at Mars
- The Mars 3 descent module separated from the orbiter and several hours later entered the Martian atmosphere, descending to the surface via a series of parachutes and retrorockets
- Once safely on the surface, the Mars 3 lander opened its four petal-shaped covers to release the 4.5-kg PROP-M rover contained inside
- Although it only transmitted for 20 seconds it was the first spacecraft to survive a Mars landing long enough to transmit anything
- Due to unknown causes, the Mars 3 lander was never heard from or seen again
- The Search
- The largest Russian Internet community about Curiosity has been looking through data from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter, looking for the lost lander.
- Subscribers did the preliminary search for Mars 3 via crowdsourcing
- Coordinators modeled what Mars 3 hardware pieces should look like in a HiRISE image, and the group carefully searched the many small features in this large image, finding what appear to be viable candidates
- The predicted Mars 3 landing site was at latitude 45 degrees south, longitude 202 degrees east, in Ptolemaeus Crater
- HiRISE acquired a large image at this location in November 2007, and promising candidates for the hardware from Mars 3 were found on Dec. 31, 2012
- Likely Features
- Four features from the image resemble four pieces of hardware from the Mars 3 mission: the parachute, heat shield, terminal retrorocket and lander.
- Each candidate has a size and shape consistent with the expected hardware, and they are arranged on the surface as expected from the entry, descent and landing sequence
- A follow-up image by the orbiter from last month shows the same features
- Further analysis of the data and future images to better understand the three-dimensional shapes may help to confirm this interpretation
- Off all the feature the the candidate parachute is the most distinctive feature, an especially bright spot for this region, about 8.2 yards (7.5 meters) in diameter
- The parachute would have a diameter of 12 yards (11 meters) if fully spread out over the surface
- This set of features and their layout on the ground provide a remarkable match to what is expected from the Mars 3 landing, but alternative explanations for the features cannot be ruled out
- Multimedia
- Image | Graphic of the lander pieces and candidates | Credit: Vitali Eerogov
- Image | Could This Be the Mars Soviet 3 Lander? | nasa.gov
- Further Reading / In the News
- Mars 3 | Wikipedia
- Mars orbiter images may show 1971 Soviet lander | Phys.org
- Soviet Lander Spotted by Mars Orbiter | UniverseToday.com
- NASA Mars Orbiter Images May Show 1971 Soviet Lander | masr.jpl.nasa.gov
- New Mars Photos May Reveal 1970s Soviet Lander | Space.com
— TWO-BYTE NEWS —
Comet Aiming to Hit Mars is Going to Miss
- The Discovery
- The comet C/2013 A1 was discovered in the beginning of 2013 by comet-hunter Robert McNaught at the Siding Spring Observatory in New South Wales, Australia
- When the discovery was initially made, astronomers looked back over their observations to find “prerecovery” images of the comet dating back to Dec. 8, 2012.
- These observations placed the orbital trajectory of comet C/2013 A1 right through Mars orbit on Oct. 19, 2014
- New Observations
- The latest orbital plot places the comet’s closest approach to Mars slightly closer than previous estimates
- The new data has also significantly reduces the probability the comet will impact the Red Planet, JPL said, from about 1 in 8,000 to about 1 in 120,000.
- The closest approach is now estimated at about 68,000 miles (110,000 kilometers). The most previous estimates had it whizzing by at 186,000 miles (300,000 kilometers).
- The latest estimated time for close approach to Mars is about 11:51 a.m. PDT (18:51 UTC) on Oct. 19, 2014
- Future observations of the comet are expected to refine the orbit further
- Multimedia
- YouTube | Animation of the Orbit of Comet C 2013 A1 and MArs | INSANE! COMET C 2013 A1 (SIDING SPRING) comes close to MARS | Valeria Gusmão
- Further Reading / In the News
- New Calculations Effectively Rule Out Comet Impacting Mars in 2014 | UniverseToday.com
Glasses That Read to You
- Where it Started
- The project began with a challenge issued by faculty member Seema Pissaris, founder of Games Trader
- Last fall, Pissaris urged students in several of her classes to think about developing a social entrepreneurship project
- It has now has been hailed by venture investors as a potentially breakthrough product that could make a difference for disabled people worldwide
nt - EyeTalk
- Eyetalk is designed to be portable, affordable, and operate without requiring an Internet connection
- It will allow a blind user to access printed material while walking around a store or library, which now requires bulkier, more expensive equipment
- Future versions of Eyetalk will target a global market and enable users to hear information aloud in one of many languages.
- An early prototype, known as the FreedomLens, was one of 16 semi-finalists chosen from 29 nations to present at the 2013 Global Social Entrepreneurship Competition (GSEC), February 25-30 at the University of Washington\’s Foster School of Business in Seattle
- Multimedia
- YouTube | EYETalk: read printed text to the blind | equityplus
- YouTube | Demonstration of glasses that read for you | FloridaInternational
- Further Reading / In the News
- Eyes4Blind.com
- Eyeglasses read to the blind | Phys.org
— VIEWER FEEDBACK —
Visiting Mars
- Jacob F. Roecker @jacobroecker
- If we landed someone on mars would they go to the same spot as the rovers or pick someplace new?
- My Opinion
- It’s not cheating to say it depends.
- We will use Mars Reconnaissance Orbiter, MRO, to help determine the best locations to land
- There will be specific qualifications for a landing site including soil composition and terrain
- On one hand, you want to be able to break all new science in different locations, possibly where rovers would have a hard time going
- On the other hand, if one of the rovers find some very exciting data it might sense to go back to that location where
— CURIOSITY UPDATE —
- Conjunction
- YouTube | Mars in a Minute: What Happens When the Sun Blocks our Signal? | JPLnews
- Curiosity Rover Report
- YouTube | Curiosity Rover Report (April 12, 2013): Mars\’ Bygone Atmosphere | JPLNews
- Social Media
- Curiosity Rover @MarsCuriosity
- Further Reading / In the News
- Curiosity Webpage | What\’s New | Mars.JPL.NASA.gov
SCIENCE CALENDAR
Looking back
- April 17, 1930 | 93 years ago | Synthetic rubber | The discovery of a new rubber-like compound was recorded by Dr. Arnold M. Collins in his laboratory notebook. He had noticed that a mixture that had stood from some weeks before, had solidified “to white, somewhat rubber-like masses,” from polymerization of monovinylacetylene mixed with concentrated HCl. He theorized the new compound was 2-chloro-1,3-butadiene. His research group at the Du Pont Company, over the next several weeks, but only gradually, recognized its potential as the first synthetic rubber. Wallace Carothers named it chloroprene. It was announced as DuPrene on 2 Nov 1931. From 1936, it is known as Neoprene.
- After more development, it was sold as a material useful for products impervious to oil, for electrical wire insulation and as a coating compound. It is now used in a wide variety of applications, such as laptop sleeves, orthopedic braces (wrist, knee, etc.), electrical insulation, liquid and sheet applied elastomeric membranes or flashings, and automotive fan belts
Looking up this week
- Keep an eye out for …
- Thurs, April 18 | The moon is first quarter phase
- The \”Sickle of Leo,\” the \’head\’ of the lion (Leo) | It looks like a backwards question mark with the brightest star at the base | On Fri (Apr 19) look to the upper left of the Moon, on Sat (Apr 20) look above the Moon, and on Sun (Apr 20) look to the upper right of the Moon
- Jupiter | After sunset | Will rise in the west, moving towards the horizon until 11-12 when it sets. The red giant star Aldebaran still sits below Jupiter
-
Saturn | End of Twilight | Lies low in the E-SE, rising all evening. It\’s highest in the sky around 1-2am DST
-
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