Cool Science Story Of The Day [Continuing Thread]

[cstreit]

Originally Posted by Hawkeye's-911T

BBC - Future - Technology - Wireless highway charges electric cars as they go

Maybe not "a cool science story" but interesting stuff all the same re: electric cars
Cheers
JB

You know, a metallic strip in the road could do this... then the car could just have a pin that extends down into a slot in the road to self guide.

[kach22i]

Top Ten Inventions.......in energy and mechanics
Top 10 inventions in energy and mechanics

[Aragorn]

Looks like manned missions to Mars may take some more research and development.


Space radiation results should spark manned Mars mission debate | Science | guardian.co.uk

[Aragorn]

I did not know this about stars.

Scientific Breakthrough Reveals Stars Consist Primarily Of Twinkles | The Onion - America's Finest News Source

[RWebb]

To improve today’s concrete, do as the Romans did

[kach22i]

Originally Posted by RWebb

To improve today’s concrete, do as the Romans did

Seawater is full of organics, which makes this even more unexpected.

They don't touch on that in the article, but it's the reason you want to use washed and graded sand/aggregate in your mix.

[sammyg2]

[IROC]

New battery technology developed here at work:

Oak Ridge National Laboratory - New all-solid sulfur-based battery outperforms lithium-ion technology

The new ionically-conductive cathode enabled the ORNL battery to maintain a capacity of 1200 milliamp-hours (mAh) per gram after 300 charge-discharge cycles at 60 degrees Celsius. For comparison, a traditional lithium-ion battery cathode has an average capacity between 140-170 mAh/g. Because lithium-sulfur batteries deliver about half the voltage of lithium-ion versions, this eight-fold increase in capacity demonstrated in the ORNL battery cathode translates into four times the gravimetric energy density of lithium-ion technologies, explained Liang.

[scottmandue]

Originally Posted by Aragorn

Looks like manned missions to Mars may take some more research and development.


Space radiation results should spark manned Mars mission debate | Science | guardian.co.uk

I have been saying this for years... but hey, don't let science fact get in the way of our science fiction fantasies of playing Frisbee on Mars.

[RWebb]

nice -- maybe we need a battery thread, Mike

[HHI944]

Originally Posted by IROC

New battery technology developed here at work:

Oak Ridge National Laboratory - New all-solid sulfur-based battery outperforms lithium-ion technology

So, does this mean we will finally see a damn cell phone battery that lasts all day?

[john70t]

The Optical Society - Scientists Mimic Fireflies to Make Brighter LEDs
A GaN LED, coated with a "factory-roof" pattern modeled off the fireflies’ scales. The bio-inspired LED coating increased light extraction by more than 50 percent.

[porsche4life]

Whoa... That's cool. I wonder if our engineers have seen that at my company. We are always trying to maintain brightness but decrease power consumption..

[john70t]

Shark-Inspired Boat Surface -- Materials Engineers Turn to Ferocious Fish for Nonstick Ship Coating
"Brennan designed the surfaces to prevent algae and barnacles from growing on boats. He says, "We started making surfaces that are mimicking the shark's skin."
"Scientists have found that the ridges created by shark scales can reduce drag in the water by as much as 8 percent."

[rfloz]

The study of evolution has in large part evolved (devolved?) into statistical analysis of DNA.

While I have some confidence in the DNA data, I am less certain of the applied statistics. In almost every study I have seen, there is buried somewhere in the statistical analysis some "fudge factor". Among the most common is the asumption that DNA mutates at some given rate from time eternal. Thus the "mother of all humans lived XXX,XXX years ago" sort of finding. That fudge factor has been challenged and, IIRC, changed at least twice.

The article below is a bit different, but relies on statistics rather than hard data to argue for the date of a very important event.

Is this good science? Does no one go into the field anymore?


From sciencedaily.com

"Scientists Date Prehistoric Bacterial Invasion Still Present in Today's Plant and Animal Cells

June 19, 2013 — Long before Earth became lush, when life consisted of single-celled organisms afloat in a planet-wide sea, bacteria invaded the ancient ancestors of plants and animals and took up permanent residence. One bacterium eventually became the mitochondria that today power all plant and animal cells; another became the chloroplast that turns sunlight into energy in green plants.

39A new analysis by two University of California, Berkeley, graduate students more precisely pinpoints when these life-changing invasions occurred, placing the origin of photosynthesis in plants hundreds of millions of years earlier than once thought.

"When you are talking about these really ancient events, scientists have estimated numbers that are all over the board," said coauthor Patrick Shih. Estimates of the age of eukaryotes -- cells with a nucleus that evolved into all of today's plants and animals -- range from 800 million years ago to 3 billion years ago.

"We came up with a novel way of decreasing the uncertainty and increasing our confidence in dating these events," he said. The two researchers believe that their approach can help answer similar questions about the origins of ancient microscopic fossils.

Shih and colleague Nicholas Matzke, who will earn their Ph.Ds this summer in plant and microbial biology and integrative biology, respectively, employed fossil and genetic evidence to estimate the dates when bacteria set up shop as symbiotic organisms in the earliest one-celled eukaryotes. They concluded that a proteobacterium invaded eurkaryotes about 1.2 billion years ago, in line withearlier estimates.

They found that a cyanobacterium -- which had already developed photosynthesis -- invaded eukaryotes 900 million years ago, much later than some estimates, which are as high as 2 billion years ago.

Previous estimates used hard-to-identify microbial fossilsor ambiguous chemical markers in fossils to estimate the time when bacteria entered ancestral eurkaryotic cells, probably first as parasites and then as symbionts. Shih and Matzke realized that they could get better precision by studying today's mitochondria and chloroplasts, which from their free-living days still retain genes that are evolutionarily related to genes currently present in plant and animal DNA.

"These genes, such as ATP synthase -- a gene critical to the synthesis of the energy molecule ATP -- were present in our single-celled ancestors and present now, and are really, really conserved," Matzke said. "These go back to the last common ancestor of all living things, so it helps us constrain the tree of life."

Since mitochrondrial, chloroplast and nuclear genes do not evolve at exactly the same rate, the researchers used Bayesian statistics to estimate the rate variation as well as how long ago the bacteria joined forces with eukaryotes. They improved their precision by focusing on plant and animal fossils that have more certain dates and identities than microbial fossils.

The paper appeared online on June 17 in advance of publication in the journal Proceedings of the National Academy of Sciences. Matzke also is a member of UC Berkeley's Center for Theoretical Evolutionary Genomics. (Emphasis added)

Story Source:

The above story is reprinted from materials provided by University of California - Berkeley. The original article was written by Robert Sanders.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


--------------------------------------------------------------------------------

Journal Reference:

1.P. M. Shih, N. J. Matzke. Primary endosymbiosis events date to the later Proterozoic with cross-calibrated phylogenetic dating of duplicated ATPase proteins. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1305813110

Need to cite this story in your essay, paper, or report? Use one of the following formats:
APA

MLA University of California - Berkeley (2013, June 19). Scientists date prehistoric bacterial invasion still present in today's plant and animal cells. ScienceDaily. Retrieved June 28, 2013, from http://www.sciencedaily.com*

[masraum]

Originally Posted by rfloz

I ran across this site while looking for a specific science article -
ScienceDaily: Latest Science News

It's free and covers material form a very wide array of scientific publications.

Essentially, it gives an abstract of a given article in lay terms, but also gives a link to the complete article. Some of the latter have restricted access, but many seem to be open to all and free.

I check this one.

Science News

[RWebb]

the asumption that DNA mutates at some given rate from time eternal is called the molecular clock hypothesis

[rfloz]

Originally Posted by RWebb

the asumption that DNA mutates at some given rate from time eternal is called the molecular clock hypothesis

Having a fancy name for a fudge factor doesn't make it good science. Or does it?

[rfloz]

Originally Posted by masraum

I check this one.

Science News

Thanks. I'll give it a look.

[kach22i]

Originally Posted by RWebb

the asumption that DNA mutates at some given rate from time eternal is called the molecular clock hypothesis

I did not know this - cool.


Scientists discover thriving colonies of microbes in ocean 'plastisphere'
Jun 27, 2013
Scientists discover thriving colonies of microbes in ocean 'plastisphere'

(Phys.org) —Scientists have discovered a diverse multitude of microbes colonizing and thriving on flecks of plastic that have polluted the oceans—a vast new human-made flotilla of microbial communities that they have dubbed the "plastisphere."

........Using scanning electron microscopy and gene sequencing techniques, they found at least 1000 different types of bacterial cells on the plastic samples, including many individual species yet to be identified.

.........................On the other hand, the scientists also found evidence that microbes may play a role in degrading plastics. They saw microscopic cracks and pits in the plastic surfaces that they suspect were made by microbes embedded in them, as well as microbes possibly capable of degrading hydrocarbons.