marți, 27 noiembrie 2012

http://www.crackajack.de/2012/11/23/edgar-allan-poe-imagined-by-a-vintage-japanese-magazine/



Researchers have built microscopic pyramids as cages for growing cells

This photograph may look like an artifact from an alien world (one with similar taste in architecture to the Egyptians), but it actual depicts a cell living in a pyramid-shaped cage, one that helps us view cells in something closer to their natural environment.
One of the problems with studying cells in a petri dish is that you're viewing them in a flat environment rather than in something resembling three-dimensional tissue. This technique, known as corner lithography, allows researchers to study cells in a controlled environment while coming closer to mimicking tissue. Researchers from the University of Twente in the Netherlands created these cages by placing nitrides over silicon pits and then peeling away most of the material. Some of the material remains in the corners, forming a pyramid.
Since the pyramids are open at the sides and are sufficiently close to one another, the cells are still able to interact for the most part as they normally would, unaware of and unimpeded by their cages.
Now we just need to wait for someone to make a commemorative corner lithography D4.
You can read more about the process in the August 21st issue of Small.
Photo from the University of Twente.

marți, 30 octombrie 2012

Halloween is a celebration of the living dead, the harvest of autumn, people, parties, pyramids and americans






Today, Primrose Hill in north London is a park offering views of the city. But in 1829, with a squeeze on burial space in the capital, architect Thomas Willson planned a pyramid mausoleum to hold up to five million bodies.
Willson, born in 1780 and trained at the Royal Academy, wanted the pyramid to be 94-storeys high and cover a site of 18 acres, (7000 sq m). ”It was supposed to be compact, hygienic and ornamental,” says Catharine Arnold, an expert on London’s dead. ”Willson hoped people would come to admire this huge pyramid from far and wide, picnicking on Primrose Hill and enjoying this splendid monument. But it would be rather like a giant car-park of the dead,” says Arnold.
The pyramid-design caught the public’s mood for Egyptiana – the height of fashion at the time. Winding walks, similar to today’s Guggenheim Museum in New York, were planned to transport the bodies through the pyramid’s catacombs to their final resting places.
Why didn’t it happen?
“It would have been monumental, but grotesque – a literal Valhalla,” says author Simon Jenkins. ”Public opinion stopped it. The arguments for leaving the site wild won the day and Primrose Hill became one of London’s most popular parks.”
Willson claimed the pyramid would make £10m profit when full, but there was suspicion among the authorities that his figures did not add up. There was also concern that the weight of the bricks may have crushed Primrose Hill. And the public mood turned against necropolises – cities of the dead – as garden-style cemeteries became the norm. With the building of Highgate cemetery in 1829, the pyramid scheme was finally shelved. Via The landmark buildings that never were.















marți, 9 octombrie 2012


bioaccumulation




http://esciencenews.com/dictionary/mutant.plants

Logo of genetics
Genetics. 1998 June; 149(2): 579–595.
PMCID: PMC1460208

A genetic screen for modifiers of UFO meristem activity identifies three novel FUSED FLORAL ORGANS genes required for early flower development in Arabidopsis.

Abstract

In a screen to identify novel genes required for early Arabidopsis flower development, we isolated four independent mutations that enhance the Ufo phenotype toward the production of filamentous structures in place of flowers. The mutants fall into three complementation groups, which we have termed FUSED FLORAL ORGANS (FFO) loci. ffo mutants have specific defects in floral organ separation and/or positioning; thus, the FFO genes identify components of a boundary formation mechanism(s) acting between developing floral organ primordia. FFO1 and FFO3 have specific functions in cauline leaf/stem separation and in first- and third-whorl floral organ separation, with FFO3 likely acting to establish and FFO1 to maintain floral organ boundaries. FFO2 acts at early floral stages to regulate floral organ number and positioning and to control organ separation within and between whorls. Plants doubly mutant for two ffo alleles display additive phenotypes, indicating that the FFO genes may act in separate pathways. Plants doubly mutant for an ffo gene and for ufo, lfy, or clv3 reveal that the FFO genes play roles related to those of UFO and LFY in floral meristem initiation and that FFO2 and FFO3 may act to control cell proliferation late in inflorescence development.

Full Text

The Full Text of this article is available as a PDF (916K).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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