Fossilized Feathers

Not long ago, extinct dinosaurs were considered by most as scaly and dull. All the known fossils of primitive birds (stem avians) could easily fit on a desk and our only look at Mesozoic [250 to 65 million years ago (Ma)] feathers (except for a few isolated plumes) was Archaeopteryx, a theropod dinosaur considered by most to be the most primitive bird.


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Selection for positive illusions

Everybody knows that overconfidence can be foolhardy. But a study reveals that having an overly positive self-image might  confer an evolutionary advantage if the rewards outweigh the risks


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Growth of Cities Endangers Global Environment, According to New Analysis

ScienceDaily (Aug. 19, 2011) — The explosive growth of cities worldwide over the next two decades poses significant risks to people and the global environment, according to a meta-analysis published August 19 in PLoS ONE.

Researchers from Yale, Arizona State, Texas A&M and Stanford predict that by 2030 urban areas will expand by 590,000 square miles -- nearly the size of Mongolia -- to accommodate the needs of 1.47 billion more people living in urban areas.
Urban areas, they found, have been expanding more rapidly along coasts. "Of all the places for cities to grow, coasts are the most vulnerable. People and infrastructure are at risk to flooding, tsunamis, hurricanes and other environmental disasters," said Seto.

"It is likely that these cities are going to be developed in places that are the most biologically diverse," said Karen Seto, the study's lead author and associate professor in the urban environment at the Yale School of Forestry & Environmental Studies. "They're going to be growing and expanding into forests, biological hotspots, savannas, coastlines -- sensitive and vulnerable places."

The study provides the first estimate of how fast urban areas globally are growing and how fast they may grow in the future. "We know a lot about global patterns of urban population growth, but we know significantly less about how urban areas are changing," she said. "Changes in land cover associated with urbanization drive many environmental changes, from habitat loss and agricultural land conversion to changes in local and regional climate."

The researchers examined peer-reviewed studies that used satellite data to map urban growth and found that from 1970 to 2000 the world's urban footprint had grown by at least 22,400 square miles -- half the size of Ohio.

"This number is enormous, but, in actuality, urban land expansion has been far greater than what our analysis shows because we only looked at published studies that used satellite data," said Seto. "We found that 48 of the most populated urban areas have been studied using satellite data, with findings in peer-reviewed journals. This means that we're not tracking the physical expansion of more than half of the world's largest cities."

Half of urban land expansion in China is driven by a rising middle class, whereas the size of cities in India and Africa is driven primarily by population growth. "Rising incomes translate into rising demand for bigger homes and more land for urban development, which has big implications for biodiversity conservation, loss of carbon sinks and energy use.

http://www.sciencedaily.com/releases/2011/08/110819155428.htm

McLaren F1 MP4-23

McLaren MP4-23

McLaren Mercedes Vodafone, este es el auto con el que McLaren en el 2008 con Lewis Hamilton ganó el Campeonato Mundial de pilotos de Fórmula Uno. A mi juicio el auto más bonito y vistoso que a corrido en cualquier campeonato del mundo de cualquier categoría.  

Cuartos de final de la Champions League

Geobacter project

Pagina web dedicada al Geobacter sp., enfocándose a la capacidad que tienen estos microorganismos para transferir electrones a un electrodo de forma directa en una celda de combustible microbiana. La pagina ofrece una gran cantidad de full papers que este grupo de investigación (Geobacter project) a realizado.
http://www.geobacter.org/

Congreso AMIDIQ 2011

El comité técnico de la AMIDIQ ha extendido la fecha para el envío de los trabajos en extenso hasta el 2 de Abril 2011.


Congreso AMIDIQ 2011, 3 al 6 de mayo, 2011 Riviera Maya, Quintana Roo