[escepticos] Revista de prensa

["Antoni Mont" <josep.mont@...>]

En el NewScientist de esta semana vienen algunas reseñas sobre temas que
se han tocado recientemente:

1)Experimentación con animales (Para Arturo)

Un toque de atención ante el alarmante aumento en el número de ratones
transgénicos utilizados en experimentación, que en Gran Bretaña se ha
multiplicado por siete en el transcurso de la presente década. Por
supuesto desde una óptica racional, en la misma linea que lo comenta
Javier Armentia.

Hidden sacrifice
Andy Coghlan
"Laboratory animals have always had to be be humanely killed, once they
can no longer be used in experiments or for breeding. But genetic
engineering makes the problem worse. When researchers inject new genes
into animal embryos, only between 1 and 10 per cent of them will
incorporate the gene.(....)"

http://www.newscientist.com/ns/19990508/newsstory1.html

2)A vueltas con el Archaeopteryx (Para Ernesto)

Un capítulo mas en la polémica sobre como empezó el vuelo de las aves.
En esta ocasión se apuesta por el despegue desde tierra en oposición al
planeo desde árboles.

Winging it
Bob Holmes, San Francisco
"So Burgers and Luis Chiappe, a palaeontologist at the Natural History
Museum of Los Angeles County, revised the calculations to take this into
account. They found that Archaeopteryx's wings would have given enough
forward thrust to accelerate the animal to takeoff velocity in just 3
seconds (Nature, vol 399, p 60).(...)"

http://www.newscientist.com/ns/19990508/newsstory5.htm

3)Tectónica de placas en Marte (Para Mario)

On the move
Jeff Hecht, Boston
"Mars seemed too small to retain enough internal heat to support the
process, but telltale features that have turned up in data from the Mars
Global Surveyor are forcing scientists to rethink their ideas. The data
show there are parallel strips of crust about 200 kilometres across and
up to 2000 kilometres long on the ancient southern highlands that are
magnetised in alternating directions.(...)
Connorney and his colleagues report the observations in two papers in
last week's Science (vol 284, p 790 and p 794).(...)"

http://www.newscientist.com/ns/19990508/newsstory6.html

And that's all folks