Wednesday, 11 July 2007

Saturday, 7 July 2007

Super-Kamiokande

It is believed soon after the big bang, when the universe was at a very high temperature, many neutrinos were produced. In addition, when a star explodes as a supernova, many neutrinos are emitted. Neutrinos are also copiously produced in nuclear reactions in the core of the sun. Also cosmic rays which come into the earth's atmosphere and interact with oxygen or nitrogen nuclei produce neutrinos. Purposes of the research are to elucidate the source of energy of the sun and detect the properties of the enigmatic neutrinos by observing these neutrinos with considerable precision.The detector consists of an inner volume and an outer volume which contain 32,000 tons and 18,000 tons of pure water respectively. The outer detector is used to veto entering cosmic ray muons and is used as a buffer to keep radiation emitted by the surrounding rock and walls from entering the inner volume. The inner detector has 11,200 photomultiplier tubes (PMTs) attached to the bottom, top and sides facing inward. The PMTs collect the pale blue light called Cerenkov light which is emitted by particles travelling fast as light in the water. By measuring the direction and intensity of this light,information about particle interactions such as neutrino interactions or proton decay can be determined (Official Website).

Monday, 2 July 2007

Simple Creatures, Intriguing Finds

Researchers look to fruit flies and tiny worms for greater understanding of neurodegenrative diseases such as Alzheimer's and Parkinson's. Fruit flies have many genes in common with higher animals, including humans. Researchers can easily transplant genes from humans into fruit flies. Finding mutations and observing the characteristics they produce are easier in fruit flies than in other types of animals.
Feany’s laboratory has bred a strain of the fruit fly Drosophila melanogaster that models Parkinson’s disease. Her team implanted mutant genes in the flies for a protein called alpha-synuclein.
Flies carrying the mutant genes lose dopamine-producing neurons in the brain’s substantia nigra, just as humans with Parkinson’s do. Also, fibrous bundles of alpha-synuclein form in the insects’ neurons. Bundles of the same structure and composition (called Lewy bodies) develop in the brain cells of people with Parkinson’s.
Cellular changes in the flies correlate with behavioral changes. Normal fruit flies climb up the sides of plastic vials. Middle-aged flies carrying the transplanted, mutant gene lose that ability.

Contents of the day

Article of the Day

Commodus

The son of Marcus Aurelius, Lucius Aurelius Commodus Antoninus was a Roman emperor who ruled from 180 to 192 CE—a period some historians view as the beginning of the empire's decline. Though his reign was relatively peaceful, Commodus was a tyrant who spent lavishly on gladiatorial combats, persecuted the Senate, and even renamed Rome after himself. He fancied himself a gladiator, frequently battling both men and animals, and considered himself the reincarnation of what mythical hero? More... Discuss

This Day in History

Liberian President William R. Tolbert Is Killed in Military Coup (1980)

Liberia was founded in the 1820s by former slaves from the US, and tensions between the Americo-Liberian minority and the indigenous majority have persisted since that time. On April 12, 1980, a group of soldiers led by Samuel Kanyon Doe stormed the executive mansion, killing Americo-Liberian President William R. Tolbert and 27 other government leaders. Doe, a member of the ethnic Krahn tribe, then declared himself president. How had a rice scandal seriously undermined Tolbert? More... Discuss

Today's Birthday

Herbert Jeffrey "Herbie" Hancock (1940)

Hancock is a jazz and funk pianist, composer, and bandleader who emerged as part of Miles Davis's group in the mid-1960s. An early adopter of electronic instruments, he became involved with funk and disco in the 70s, while continuing to tour with jazz groups, such as that of Wynton Marsalis. He won an Academy Award for his original score of the 1986 film 'Round Midnight and has won 14 Grammys, including "Album of the Year" for a work that paid tribute to what fellow musician? More... Discuss

In the News

snigger discuss

Definition:(verb) Laugh quietly.
Synonyms:snicker
Usage:The rude tourists snigger at the locals' outdated ways and dress.

Quote of the Day
Clock, n.: A machine of great moral value to man, allaying his concern for the future by reminding him what a lot of time remains to him.
Ambrose Bierce
(1842-1914)
Discuss