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that it would draw up draft guidelines to allow fertility clinics to offer the technique

The proposed guidelines would be released for public comment later this year, and Parliament could vote on a final version next year

Mitochondria are the cell's power generators, and they carry their own DNA, called mtDNA

Mutations in those genes cause mitochondrial diseases, which can affect various organs, including the heart, liver, eyes, and brain

Such diseases are passed from mother to child, because the egg provides most of an embryo's mtDNA

The techniques

transfer the nuclear DNA from the sperm and egg of the potential parents into a second egg, provided by a donor who has healthy mitochondria, from which the nuclear DNA has been removed

The technique is still under development and isn't yet considered ready to try in humans

Unlike people have been led to believe, they do not have chunks of rotting flesh from their meals on their teeth, cultivating bacteria

the poor hygiene of water buffalo is responsible for perceptions about deadly toxic bacteria in the dragons

They now populate the islands of Indonesia where they prey on the introduced water buffalo, and on pigs and deer

a pair of researchers

has discovered how fear can actually increase or decrease the ability to discriminate among sounds depending on context

study

emotional conditioning in mice to investigate how hearing acuity (the ability to distinguish between tones of different frequencies) can change following a traumatic event, known as emotional learning

In these experiments

animals learn to distinguish between potentially dangerous and safe sounds—called "emotional discrimination learning."

This type of conditioning tends to result in relatively poor learning, but

designed a series of learning tasks intended to create progressively greater emotional discrimination in the mice, varying the difficulty of the

The researchers found that, as expected, fine emotional learning tasks produced greater learning specificity than tests in which the tones were farther apart in frequency

animals presented with sounds that were very far apart generalize the fear that they developed to the danger tone over a whole range of frequencies

animals presented with the two sounds that were very similar exhibited specialization of their emotional response

pitch discrimination abilities were measured in the animals, the mice with more specific responses displayed much finer auditory acuity than the mice who were frightened by a broader range of frequencies

Another interesting finding of this study is that the effects of emotional learning on hearing perception were mediated by a specific brain region, the auditory cortex

The auditory cortex has been known as an important area responsible for auditory plasticity

Surprisingly

found that the auditory cortex did not play a role in emotional learning

the specificity of emotional learning is controlled by the amygdala and sub-cortical auditory areas

hypothesis is that the amygdala and cortex are modifying subcortical auditory processing areas. The sensory cortex is responsible for the changes in frequency discrimination, but it's not necessary for developing specialized or generalized emotional responses

when the Space Shuttle Atlantis exhibition opened

at NASA's Kennedy Space Center Visitor Complex

Atlantis dominates the center of a multistory building that allows views of the orbiter from many angles.

a Grade 10 student

designed a flashlight that provides bright light without batteries or moving parts

and only needs a five degree temperature difference to work and produce up to 5.4 mW at 5 foot candles of brightness

Using four Peltier tiles and the temperature difference between the palm of the hand and ambient air

bought Peltier tiles and tested them to see if they could produce sufficient power to light an LED

power was no problem but getting the needed voltage was, as the tiles did not generate enough of the voltage needed

some changes to the circuit design

used the Internet for information, experimented with different circuits

finding an energy-harvesting article

that made note of a circuit that could provide enough voltage when used with a recommended transformer

The final design included mounting the Peltiers on a hollow aluminum tube which was inserted in a larger PVC pipe with an opening that allowed ambient air to cool the tube

The palm wrapped around a cutout in the PVC pipe and warmed the tiles.

The result was a bright light at 5 degree Celcius [sic] of Peltier differential

Materials for the flashlight project cost her $26

The top winner gets a $50,000 scholarship and trip to the Galapagos Islands

The prize ceremony takes place in September. Winners will be chosen in different age categories—13-14, 15-16, 17-18.