Immune cells gobble up healthy but idle brain cells

USE it or lose it: a class of immune cell demolishes idle circuits and connections in the brain, even a healthy one. Understanding more about the process could help prevent the onset of degenerative brain diseases.

Until now, microglia have been dismissed as simple immune cells that do little more than protect brain cells from damage and tidy up in the aftermath of disease.

"The idea they can clean up brain debris has been well established in studies of brain disease," says http://www.childrenshospital.org/cfapps/research/data_admin/Site2674/mainpageS2674P0.html Beth Stevens of Boston Children's Hospital. "But now, even without damage, we've found them to respond to subtle changes in synaptic function."

Stevens and her colleagues manipulated mice to make one eye more active than the other, creating a disparity in activity between the two neural circuits linking the eyes to the brain.

With the help of dyes to distinguish the signals from the left and right eyes, they saw in post-mortems that microglia had preferentially pruned the connections, or synapses, from circuits serving the underactive eye. Synapses were marked out for destruction through labelling with an immune chemical called C3 (Neuron, DOI: 10.1016/j.neuron.2012.03/026).

"We think C3 is an 'eat me' signal," says Stevens.

Finding out why some synapses but not others are earmarked for elimination could point to ways of preventing degenerative brain diseases.

"Early synapse loss is a feature of many neurodegenerative diseases," says Stevens. "So there's lots of excitement about finding out what the trigger is."

"Microglia were considered to be just garbage collectors," says Francesca Peri of the European Molecular Biology Laboratory in Heidelberg, Germany. "They are turning out to be far more interesting - but before we can understand their role in disease, we need to understand what these cells do normally."

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Nasrallah demands release of Lebanese held in Syria

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Rumor: PlayStation 4 was almost finalized as a disc-less gaming ...

By Tyler Lee on 05/31/2012 04:40 PDT

Sony has yet to officially announce the PlayStation 4, but according to the rumors (via Wall Street Journal), it seems that the PlayStation 4 was almost finalized as being a disc-less device. What this meant was that in order to purchase their games, gamers would most likely have to log onto PSN and access the store to purchase and download their games digitally. While this might save on a lot of physical space, it would eventually eat up a lot of storage on the gaming console. Not to mention we?re sure that there are gamers out there who would rather own physical copies of their games.

This is no doubt a relief to some gamers, but most likely a huge relief to gaming retailers who would not profit from the sales of digital games. Now according to the same report, Microsoft agrees with Sony?s decision and contrary to previous rumors, Microsoft?s next-gen Xbox (codenamed Durango) will also feature a disc drive. Given that both of these gaming consoles have yet to be announced or acknowledged, we?re not really sure what to make of rumors about a device that may or may not exist. Until more concrete evidence has been uncovered, and Sony/Microsoft issue an official statement themselves, we suggest taking this with a grain of salt for now.

Related articles:
Rumored PlayStation 4 specs leaked again
Sony PlayStation 4 rumored to be released before the Xbox 720
PlayStation 4 to be called ?Orbis?, possible winter 2013 release [Rumor]

Seen at: cinemablend?? Add a Comment?&nbsp playstation 4?sony?

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Congress Extends Flood Insurance for 60 Days

?

On May 30, 2012, the House of Representatives passed a 60-day extension of the National Flood Insurance Program (NFIP). This temporary extension enables the Senate to act on the NAR-supported five-year reauthorization and reform bill this June. The short-term extension bill was being held up by Senator Tom Coburn (R-OK) who threatened to let the NFIP shut down, yet again, unless his demands were met regarding federal tax dollars subsidizing vacation homes.

To meet these demands, the Senate agreed to a provision that creates a four-year phase-out of rate subsidies on non-primary residences. ?The phase-out provision means that the insurance rate on some non-primary residences would increase by 25 percent per year until premiums reached the full (actuarial) cost. While the first step increase is currently scheduled to take effect on July 1, 2012, the rest of the increases would not be fully phased-in for a minimum of four years. Although NAR strongly objected to mixing provisions of the larger reform bill with the temporary extension, the elimination of the rate subsidies was a necessary compromise in the face of overwhelming bipartisan support in both the House and Senate for the provision.

The compromise now in place prevents a potentially catastrophic lapse of the NFIP for both the short and long term.? Flood insurance is required by law to obtain a mortgage in more than 21,000 communities nationwide. A lapse would have affected 1,300 transactions per day, or nearly 40,000 a month, a potentially devastating blow to the nascent market recovery. NAR will continue to work with our Congressional allies to minimize the impact of this provision as the legislative process moves forward.

This is an important issue for Arizona REALTORS? to continue to watch as our state is impacted by flood issues from Bullhead/Mohave Valley to Sedona and down to Tucson. We need to remain vigilant in our conversations with our members of Congress on how affordable flood insurance must be available for Arizona homeowners and how the lack thereof impacts entire communities.

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Holly Mabery I am a third-generation Arizona native and REALTOR?. This year I have the great honor of serving as the 2012 President for the Arizona Association of REALTORS?. When I am not representing the great REALTORS? in our state, I am an associate broker with the Heartland Group in Keller Williams sharing & helping people in the communites of Prescott, Sedona and the Verde Valley. To see more posts by this author, click here.

Tagged as: flood insurance, insurance on second homes, National Flood Insurance Program

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Facebook Forced By Privacy Activist To Put Policy Changes Up For Worldwide Vote

Max Schrems, the Austrian founder of Europe Vs. Facebook, has forced Facebook to put?proposed policy changes?up for a vote by all its users. By mobilizing his privacy group to flood Facebook's Site Governance page with pasted messages, many more than 7,000 comments were received on the proposal -- the threshold for triggering a vote. Europe Vs. Facebook is demanding sweeping changes to Facebook's product rather than the small policy changes found in the proposal Today the one-week voting period opens on a set of a relatively benign changes and Facebook will notify users by web and mobile. If over 30% of Facebook's active users, or 230 million people, vote for the changes they'll go into effect, and if they vote against they'll be scrapped. Otherwise Facebook will take the changes "under advisory".?Facebook's Chief Privacy Officer for Policy Erin Egan told me yesterday the company will consider changing its site governance voting system to discourage votes being triggered by low-quality comments and adapt to the growing size of Facebook's user base.

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Baby Boom: Did Retained Juvenile Traits Help Birds Outlive Dinosaurs?

News | Evolution

Differences in developmental timing may have given birds their big eyes, big brains and smaller size

By Sarah Fecht ?| May 31, 2012?|

Image: Frank Ippolito, American Museum of Natural History

Why do testicles hang the way they do? Is there an adaptive function to the female orgasm? What does it feel like to want to kill yourself? Does ?free will?...

Read More??

Birds are the only dinosaurs that have survived into modern times. Why is that? Of all the dinosaur species, how did they manage to make it through the catastrophic events of 65 million years ago, whereas all their fellow dinos perished? A new study, published May 27 in Nature, hints at an evolutionary phenomenon that may have played to birds' advantage: They are, it seems, baby dinosaurs whose biology prevents them from ever growing up. (Scientific American is part of Nature Publishing Group.)

Bhart-Anjan Bhullar and his doctoral advisor, Arkhat Abzhanov, posit that birds may have evolved from dinosaurs by a process known as paedomorphosis, whereby an organism retains juvenile traits even after it becomes sexually mature. "They certainly look to have some paedomorphic characteristics," says Jack Horner, a Montana State University paleontologist who studies dinosaur growth and development and was not involved in the study. Paedomorphosis "is not uncommon in evolution and speciation," he adds.

Bhullar and Abzhanov reached this conclusion by comparing the skulls of birds and dinosaurs across phylogenies, or related groups, and at different developmental stages. To quantitatively compare cranial geometries, they scanned the skulls of theropod dinosaurs (which are thought to be birds' ancestors), crocodiles and alligators (dinosaurs' cousins), early transitional birds such as Archaeopteryx, and modern birds. Then they created digitized versions of each skull and mapped out cranial landmarks, such as nostril tips, eye socket dimensions and places where bones meet.

Their measurements showed that whereas a typical non-avian dinosaur began life with a round head, large eyes and a big brain (relative to the rest of the body) then later developed an elongated snout and smaller relative brain size, birds kept their baby faces.

If birds did evolve by paedomorphosis, they join species such as axolotls. These salamanders evolved to retain tadpolelike gills and fins and, unlike most other amphibians, remain aquatic into adulthood. This feature appears to be due to a hormone disruption. By adding thyroid hormone into their water, researchers have caused axolotls to metamorphose into terrestrial salamanders.

But why would it be advantageous for adult animals to look like kids? Greg Erickson, who studies evolutionary morphology at The Florida State University and was not involved in the study, says that paedomorphosis can help a species to develop new adaptations and exploit new niches. In particular, he suggests that paedomorphosis may have enabled birds to develop larger eyes, which aid in spatial assessment during flight as well as a high brain-to-body-mass ratio, which may contribute to intelligence.

An even simpler explanation is that kids are small and, in times of environmental stress, small is good. Bhullar cites an example of Temnospondyli?large primitive amphibians that were common before 120 million years ago. Catastrophic events killed off most of the temnospondyli, except for a few paedomorphic species. "The interesting thing to me is that [after the catastrophe] these little paedomorphic animals were at the base of a giant radiation," Bhullar says. He suggests that a similar phenomenon may have occurred during the catastrophic events that killed the dinosaurs?being small may have been an advantage, because smaller animals require less food and can more easily hide. "Everything that lived on land and weighed more than one kilogram perished," Bhullar says. "The only dinosaurs that survived were the paedomorphic ones." And after many of those larger species went extinct, the little dino may have been better placed to exploit the new niches that opened up.

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BLACK SABBATH Volume Four music review by Conor Fynes

'Volume Four' - Black Sabbath (7/10)

Each album that Black Sabbath released up to the point of "Volume Four" had showcased some sort of development. After all, most great bands are rarely satisfied with staying in the same place for so long, and it would be natural for these Birmingham gents to want to explore their 'heavy metal' invention in different ways. Although the diversified approach of "Master of Reality" surprised me when compared to what came before it, "Volume Four" is an even greater leap forward for the band, at least stylistically speaking. Here, the progenitors of heavy metal are embracing the progressive rock movement that was reaching its peak around 1972; if not accepting it with open arms, then at least acknowledging it with a nod and a wave. For all of the new possibilities that Sabbath open for themselves here however, I cannot help but miss the heaviness of their earlier work.

Although I do not hide my love for progressive rock, much of the reason that albums like Black Sabbath's debut and their masterpiece "Paranoid" appealed to me so much was due to Tony Iommi's mastery of the almighty riff. Not only that, but his guitar tone was heavy and thick, even by today's standards. While "Volume Four" has not entirely lost these traits, it's clear from the uncharacteristically mellowed intro to "Wheels of Confusion" that Black Sabbath are trying to do something different with their music, for better and worse. While "Volume Four" may not be as heavy as what came before, the incorporation of prog rock and American psychedelia is an exciting change of pace. The eight minute rocker "Wheels of Confusion" and beautiful mellotron-laden "Changes" are major tips of the hat to prog, which was reaching its artistic peak that year with albums like Yes' "Close To The Edge" and Genesis' "Foxtrot". Among the other unconventional pieces on the album is a listless sound experiment in "FX", and "Laguna Sunrise", an acoustic piece accompanied by full-blown string orchestration that could easily score the happy ending to a Spaghetti Western film.

"Supernaut" has Tony Iommi evoke the spirit of Jimi Hendrix with a playful central riff that ranks among the band's best. "Snowblind" is a rocking fan favourite involving the band's love of the Businessman's drug. Although the instrumentation generally feels less defined and powerful than it did on earlier albums, Ozzy Osbourne gives one of the best vocal performances of his career here, his distinctive voice complimented with a trembling vibrato and greater range than previously expressed. The result is an album that often feels more like hard rock than metal in the traditional sense. The songwriting is layered with keyboards, and tricks that the band innovated on "Master of Reality" have been developed further here. Although this is the most musically sophisticated album the band had made yet, it lacks the same atmospheric intensity I felt so profoundly with their early work. Although they have sacrificed an aspect of their sound on "Volume Four", Black Sabbath's newfound progressive outlook on their music would open a world of new possibilities for them.

Conor Fynes | 4/5 | 2012-5-31

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