- Descifradas las ondas atmosféricas de Venus, que podrían explicar la superrotación de su atmósfera
El
planeta Venus gira muy lentamente sobre sí mismo, tanto que un día allí
dura 243 días terrestres. Pero su atmósfera, que debería rotar también
despacio, circunda el planeta en apenas cuatro días. El motor que
origina esta superrotación atmosférica aún se desconoce, aunque las
numerosas ondas que pueblan la atmósfera del planeta podrían jugar un
papel importante. Un estudio liderado por el Consejo Superior de
Investigaciones Científicas (CSIC) ha identificado la naturaleza de
estas ondas por primera vez.
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- Dispersal 'key to reptile survival'
Reptiles whose gender depends on temperature must become more widespread
to survive the effects of climate change, according to new research.
- Bird decline 'smoking gun' for pesticide's effects
The widespread use of a type of insecticide that has been blamed for
honeybee deaths is linked to a marked decline in bird numbers in Europe,
a report says.
- ¿HASTA QUE PUNTO ES CIENCIA FICCIÓN LA MINERÍA ESPACIAL?
Las principales agencias espaciales están apostando por la exploración
de asteroides que, no sólo contienen claves sobre el origen del Sistema
Solar, sino que son fuente prácticamente inagotable de metales y otros
compuestos esenciales.
- Transforming human brain imaging,
discrimination that's skin deep, seizures in glioma, and much more in
the 9 July 2014 issue of Science Translational Medicine.
- Physicists spot potential source of 'Oh-My-God' particles
For decades, physicists have sought the
sources of the most energetic subatomic particles in the universe—cosmic
rays. Now, scientists have observed a broad "hotspot" in the sky in
which such they seem to originate. Although not definitive, the
observation suggests the cosmic rays emanate from a distinct source near
our galaxy and not from sources spread all over the universe.
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- Understanding volcanic plumbing
Scientists studying the responses of ground
waves below Japanese volcanoes have devised a method for identifying
where pressurized volcanic fluids build up. This may help them better anticipate
volcanic eruptions going forward. Although scientists have known that
seismic waves from large earthquakes agitate volcanic systems, they have
not been able to determine the specific physical changes seismic waves
cause. They do know that large volcanic eruptions are preceded by the
build-up of pressurized volcanic fluids at depth. Therefore,
understanding the state of these fluids could help better anticipate
future eruptions.
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- Multiple sexual signals: calls over colors for mate attraction in an aposematic, color-diverse poison frog
Sexual signals indicate species identity and mate quality, and their
importance for mate attraction is largely recognized. Recently, research
in animal communication has started to integrate multiple signal
modalities and evaluate their interactions. However, mate choice
experiments across animal taxa have been limited to laboratory
conditions, and assessments of multiple sexual signals under field
conditions are still lacking. We take advantage of the divergence in
visual and acoustic signals among populations of the Neotropical poison
frog Oophaga pumilio to evaluate the importance of male
advertisement calls and color patterns in female mate selection.
Previous mate choice experiments in this species suggested
color-assortative female mate preferences across many populations.
Nevertheless, acoustic signals are crucial for sexual selection in
frogs, and males of O. pumilio use advertisement calls to attract
females. We hypothesize that both advertisement calls and coloration
affect female mate selection in O.pumilio. To test this
hypothesis we tested 452 receptive females from six populations in Costa
Rica and Panama in their natural home ranges for preferences regarding
local vs. non-local advertisement calls and color patterns. Overall, the
calls overrode the effect of coloration, whereby most females preferred
local over non-local calls. We found a tendency to prefer brighter (but
not necessarily local) males in two populations. Furthermore, the
strength of preferences varied geographically, and thus might be
involved in prezygotic isolation among populations. The stronger effect
of calls on mate attraction is associated with acoustic divergence
between genetic groups in the species, while color pattern diversity is
mostly located within one genetic group, i.e., not linked to large-scale
population structure. Finally our data highlights the importance to
consider an array of signal modalities in multiple wild populations in
studies of behavioral isolation.
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- A more effective step-down treatment for asthmatics: CIC or BUD?
Comparison of the efficacy of ciclesonide with
that of budesonide in mild to moderate asthma patients after step-down
therapy: a randomised parallel-group study.
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