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Posts Tagged ‘Science’

Comet impact shockwave may have planted seeds of life on Earth

13 Sep

Stanley Miller performed some of the most famous origin of life experiments, showing that the chemicals thought to be present in the early Earth's atmosphere might react to form amino acids, the building blocks of proteins. But these experiments haven't aged well, through no fault of their own; other scientists have since revised their estimates of what was present in the early atmosphere, raising some doubts as to whether the Miller experiments are especially relevant. A paper released by Nature Chemistry neatly dodges this issue by showing that it might not matter what the Earth looked like—the shockwave of a comet impact can make biological materials regardless of the composition of the atmosphere it crashes into.

In the years since Miller's experiments, we've been better able to image the composition of comets, and have even returned samples of some of the material shed by the comet Wild 2 as it approached the Sun. These have revealed a mixture of simple organic compounds like ammonia and ethanol, but nothing as complex as an amino acid, chemicals that form the building blocks of proteins.

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Video shows asteroid discoveries since 1980

08 Sep

Just in case I wasn't already in awe of the scientific progress made during my own lifetime, Lauren Submitterated (it's a verb now) this video showing the mind-blowing numbers of asteroids that have been discovered since 1980. Created by Scott Manley—and with some very lovely music, I might add—the video shows new discoveries in white, then changes their color to reflect position in relation to the inner solar system. Earth crossers are red. Earth approachers are yellow. All others are green.

Manley's included a lot of good information about what the patterns of where and when new asteroids appear in the video tell us about astronomy over over the last 30 years.

Notice now the pattern of discovery follows the Earth around its orbit, most discoveries are made in the region directly opposite the Sun. You'll also notice some clusters of discoveries on the line between Earth and Jupiter, these are the result of surveys looking for Jovian moons. Similar clusters of discoveries can be tied to the other outer planets, but those are not visible in this video.

As the video moves into the mid 1990's we see much higher discovery rates as automated sky scanning systems come online. Most of the surveys are imaging the sky directly opposite the sun and you'll see a region of high discovery rates aligned in this manner.

At the beginning of 2010 a new discovery pattern becomes evident, with discovery zones in a line perpendicular to the Sun-Earth vector. These new observations are the result of the WISE (Widefield Infrared Survey Explorer) which is a space mission that's tasked with imaging the entire sky in infrared wavelengths.



 
 

Brain surgery c. 2000 BCE

31 Aug
Archaeologists at Ikiztepe, Turkey unearthed two glass obsidian blades they believe were used for neurosurgery 4,000 years ago. Why do they think these were tools for Bronze Age brain surgery? Because they found scarred skulls there too. New Scientist interviewed excavation director Önder Bilgi:
 Data Images Ns Cms Mg20727750.200 Mg20727750.200-1 300 What makes you think they were used for surgery?

We have found traces of cuts on skulls in a nearby graveyard. Out of around 700 skulls, 14 have these marks. They could only have been cut with a very sharp tool. At this time, 4000 years ago or more, it could only have been an obsidian blade. The cut marks show that a blade was used to make a rectangular opening all the way through the skull. We know that patients lived at least two to three years after the surgery, because the skull has tried to close the wound.

Have you uncovered any clues to why this surgery was performed?

There seem to be three main reasons. The first is to relieve the pressure of a brain haemorrhage; we found traces of blood on the inside of some of the skulls. The second is to treat patients with brain cancer, as we can see pressure traces from the cancer inside some of the skulls. And the final reason was to treat head injuries, which seem to have been quite common. The people of Ikiztepe got their copper from mines in the local mountains, and we think they had to fight other local people for access to it.

"Scalpels and skulls point to Bronze Age brain surgery"



 
 

The smell of freshly-cut grass is actually a plant distress call [Mad Science]

26 Aug
The lovely scent of cut grass is the reek of plant anguish: When attacked, plants release airborne chemical compounds. Now scientists say plants can use these compounds almost like language, notifying nearby creatures who can "rescue" them from insect attacks. More »
 
 

Google Talk

25 Aug

I gave a tech talk at Google headquarters on the arrow of time, which was a lot of fun. Must be what all of Silicon Valley was like back in the boom days — pool tables, free food, volleyball, and lots of smart people everywhere. Rather than a lecture hall, the talks are held in a big lobby space where people are regularly walking through, so that passers-by can become intrigued and start listening. Also, it became clear during the questions that at least one Google employee is concerned about how to preserve intelligent life past the 10100 year mark when our universe will be nothing but empty space. Glad they’re thinking long-term!

Here is the talk, which is basically at a popular level, although I felt empowered to use the word “logarithm” without explanation. I’ve also tried to collect other talks by me onto one page, for those who just can’t get enough. (Hi, Mom!)

 
 

What’s the point of the semantic web?

20 Aug

This post was chosen as an Editor's Selection for ResearchBlogging.orgI was scanning journal tables of contents as usual this week and it occurred to me that there must be a better way to find relevant and timely research information that would be of interest to Sciencebase readers…and, of course, out pops the following title:

Technically approaching the semantic web bottleneck

Sounded, perfect…kind of…but what’s the semantic web, why’s there a bottleneck and what can be done to lube the tube?

Tim Berners-Lee’s original vision for the semantic web was that information would be just as readable (and understandable) to a person or to a machine. Digital objects, whether web page, image, video, or some other file, would have embedded within them meta data that would provide context to the content and allow software to extract meaning from the file.

Some software currently has a limited understanding of simple meta data, although any SEO will tell you that Google largely ignores web page meta data these days. That point aside, there is so much
that
might be
done if the
web were
effectively self-aware
so much that might be done if the web were effectively self-aware (not talking notions of the singularity here, just making it all more useful and easier to use). So, I asked the paper’s author, Nikolaos Konstantinou, for a few examples of how the semantic web, often referred to as Web 3.0 (although you might call it Web 2.1 or Web 2.0++), might benefit us. The first benefit would be more intelligent searches he told me, either across the web or in large-scale data repositories where intelligence is referred to in contrast to the conventional keyword-based search methods employed by the search engines.

“For instance, performing a search in Google for e.g. ‘renaissance paintings’ you will notice that among the first pages of the results returned, the vast majority contains the keywords ‘renaissance paintings’ in the respective page text (or image HTML image ‘alt’ tag),” he says. “That is because the search engine does not process the content available semantically and therefore, the results although they will be accurate, will be far from being complete. This will cause an arts student, for instance, to spend too much time finding relevant content. She would probably have to visit certain museum pages and collect the results on her own.”

This is where the semantic web would come into play, Konstantinou adds. “The vision is to get a list of what you asked for even in the case when your keyword does not exist in the web page. In the example above, a page with Leonardo da Vinci’s paintings will not be considered relevant if the words ‘renaissance paintings’ do not exist in the page. In the semantic web world the system would ‘know’ that Leonardo da Vinci is an artist of the Renaissance and therefore his works would be returned to the user performing the query.”

A second benefit would be knowledge inferred by the existing one. A system built using semantic web technologies, with the support of reasoning procedures could logically deduce informationreasoning procedures could logically deduce information, explains Konstantinou.

“The most classic example about inference is that from the statements ‘all men are mortal’ and ‘Socrates is a man’, we can deduce that ‘socrates is mortal’. This property (transitive property) in combination with a wider set of properties can augment the knowledge inserted in a system, without requiring human insertion of each and every fact, which avoids errors and reduces the workload.”

Simply, by stating 5 facts to a system, using an ontology (a glossary) and a reasoner, the system will be able to deduce 15 facts by applying logic rules (reasoning). This is in fact what allows the intelligent queries mentioned in the Renaissance example. Such a system, when asked “is socrates mortal”? will return a YES, while without reasoning the answer would be NO (or UNKNOWN in other cases). Similarly, socrates would be included in a search like “tell me all the mortals in the system”. “This is, in fact, what is meant by ‘machine understandable’ information, the ability for a machine to process information,” adds Konstantinou.

Now…how do I apply that logic to scanning tables of contents for worthy news items?

Research Blogging IconNikolaos Konstantinou, Dimitrios-Emmanuel Spanos, Periklis Stavrou, & Nikolas Mitrou (2010). Technically approaching the semantic web bottleneck Int. J. Web Engineering and Technology, 6 (1), 83-111

What’s the point of the semantic web? is a post from: Sciencebase Science Blog

 
 

Minnesota becomes a tornado state

16 Aug
This year, Minnesota had more tornadoes than any other state. If you aren't familiar with normal tornado distribution patterns, that fact is pretty surprising. It's also more than just a weird, one-time anomaly. Experts say this years' numbers seem to be part of a pattern of tornado activity becoming more common in more northerly places. Perennial champion Texas isn't throwing in the towel—it's been the tornado capital for 7 of the last 10 years—but Minnesota seems to be becoming a part of the "Tornado Alley" states, a big change from past precedent.

 
 

The mountains of Titan are formed by the moon slowly shrinking [Exogeology]

15 Aug
The mountains on Saturn's moon Titan defy easy explanation, but readings from the Cassini probe offer a fascinating new possibility: Titan is slowly releasing heat and shriveling up, causing mountains to form on its surface like wrinkles on a raisin. More »
 
 

A toothpaste-like gel that can heal wounds six times faster than normal [Medical Breakthroughs]

13 Aug
A gene therapy in the form of a thick gel is about to revolutionize wound treatment. The gel is called Nexagon, and when you apply it to a wound, it reprograms the cells to heal more quickly and efficiently. More »
 
 

A toothpaste-like gel that can heal wounds six times faster than normal [Medical Breakthroughs]

13 Aug
A gene therapy in the form of a thick gel is about to revolutionize wound treatment. The gel is called Nexagon, and when you apply it to a wound, it reprograms the cells to heal more quickly and efficiently. More »