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domingo, 30 de junio de 2013

nsf.gov - Discovery - Redefining Adaptation, the Study of How Populations Grow and Survive

Researcher also engages educators and students in an open forum.
Christopher J. Marx, Harvard University
Christopher Marx teaches organismic and evolutionary biology at Harvard University.
Credit: Christopher J. Marx, Harvard University
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vials with frozen population samples
These vials contain frozen evolved populations.
Credit: Christopher J. Marx, Harvard University
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How do organisms adapt over time? Do they evolve through a series of small beneficial steps as envisioned by Charles Darwin, or through a series of rare but large jumps? Or through a combination of both?
For example, "did a giraffe's neck get longer because there were thousands of mutations each resulting in a millimeter increase?" asks Christopher Marx, associate professor of organismic and evolutionary biology at Harvard University. "Or were there three or four changes over time that changed the size of the vertebrae dramatically?"
Marx's research focuses on adaptation, the process by which populations improve in their ability to grow and survive. "One of the major questions that we are trying to address is: What is the relative proportion of small beneficial mutations to big beneficial mutations?" he says. "And how does this outcome differ with the size of the population?"
Understanding how adaptation works in smaller populations is important because many scenarios--from new infections to cancer--involve small numbers of cells.
"Many current therapeutic approaches aim to reduce population sizes of pathogens in order to thwart their eventual success," Marx says. "This would work very well if these shrunken populations struggle to find beneficial mutations, but would be much less effective if big benefit mutations--to the pathogen or cancer--are actually fairly easy to achieve."
Until recently, many scientists held the classic Darwinian view that adaptation occurs gradually through a series of small changes, he says. Furthermore, they believed that it is extremely rare that a random mutation would actually benefit an organism in a given environment, he says.
"One consequence of the rarity of beneficial mutations would be that any improvement that arose would have a chance to take over before another beneficial mutation would arise, and would thus proceed unchallenged," Marx says. "This would lead to a series of rare, step-like jumps in performance. It would also mean that the mutations that won--rising to 100 percent of the population--would give a fairly clear picture of what is biologically possible for that organism."
In order to study adaptation, including how organisms can improve, Marx's laboratory grows hundreds of bacterial populations in the laboratory. Scientists can preserve live bacteria in an ultra-cold freezer, allowing them to revive and directly study their common ancestor, the one they used to initiate succeeding generations over time.
"Despite the diminutive physical size of these populations, each of which were grown in 1/50th of an ounce of liquid, the final population size could reach as high as 100 million cells," Marx says.
Recent work from a number of laboratories, including Marx's, has shown that beneficial mutations actually can occur much more readily than previously thought. "This changes adaptation dramatically because many innovations can arise at once and they cannot all win," he says.
He compares this competition between rival genetic innovations to what happens in a market economy when, for example, a new field opens and "many companies enter the race and, over time, the better ones beat out the weaker ones," he says.
"Because of the potential for having many new inventions present at once, the population size itself has a profound effect on adaptation," he adds. "The intuition has been that really amazing solutions to a problem are much less common than mediocre ones. Thus, the current theory is that small populations improve via little steps and big populations take big steps."
Marx is conducting his research under a National Science Foundation (NSF) Faculty Early Career Development (CAREER) award, which he received in 2009 as part of NSF's American Recovery and Reinvestment Act. The award supports junior faculty who exemplify the role of teacher-scholars through outstanding research, excellent education and the integration of education and research within the context of the mission of their organization. NSF is funding his work with $702,452 over five years.
The educational component of his grant includes a project-based lab course built around experimental evolution, and a website where scientists who work in microbial evolution can freely share educational materials.
Specifically, Marx has been studying Methylobacterium, a common microbe that lives on the surface of leaves and eats such things as methanol. "It's also the main cause of that pink scum in your shower," he says.
Based upon ongoing work evolving Methylobacterium in the laboratory, Marx and his graduate student, Nigel Delaney, have both confirmed and begun to question current beliefs.
"If you change the population size, three things are supposed to happen," he says. "The first is that big populations should adapt faster than small ones, which turns out to be true. The second is that big populations should have more infighting than little populations, which is also true. The third is that big populations will move by big steps, and small populations will move by small steps."
Their work is ongoing; however, their current data suggest that the third point might not necessarily be true. "Our small and big populations both took big steps," he says. "Big mutations can happen easily. We've seen that in our bug, and it completely changes the picture."
The experiments conducted by Marx and others using populations of microbes in the laboratory that they can control allows them to learn about the range of adaptation possibilities in a way that is difficult when directly studying infectious diseases or cancer, where there will be confounding differences in environments, starting strains or host genetics, and medical treatments.
"The recent use of sequencing to discover cancer variants within a polyp, for example, has re-discovered what researchers in the lab had already shown: many beneficial mutants tend to rise simultaneously, rather than sequentially," he says.
Marx's lab also has begun to examine the outcome of combining more than one beneficial mutation. "Do they stay equally valuable?" he says.
Last year, in a paper his team published in the journal Science, they reported on a general trend of diminishing returns. "It turns out that beneficial mutations become less valuable when combined with each other," he says.
Similarly, a University of Houston group led by Marx's friend and colleague, Tim Cooper, an assistant professor of biology, found this identical trend in the evolution of Escherichia coli.
"We had given presentations right after each other at a conference the year before and were shocked by the similarity in our work," Marx says. "That the same trend emerged in two very different systems hinted that it might be a much more widespread finding. Indeed, later papers with viruses and yeast have seen the same."
Ultimately, Marx and Cooper decided to submit their papers at the same time, because "unlike the mutations we studied, we felt our work was more valuable when combined."
--  Marlene Cimons, National Science Foundation
Investigators Christopher Marx
Related Institutions/Organizations Harvard University
Total Grants $752,447
Related Websites
Organismic Evolutionary Biology with Christopher Marx:
  The National Science Foundation.-
Guillermo Gonzalo Sánchez Achutegui
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NASA - IRIS to Take Precise Look at Sun's Energy

IRIS to Take Precise Look at Sun's Energy
June 24, 2013
The IRIS spacecraft during encapsulation inside the payload fairing of the Orbital Sciences Corp. Pegasus XL.
Image Credit: 
VAFB/Randy Beaudoin
Researchers hope NASA's latest solar observatory will answer a fundamental question of how the sun creates such intense energy.
Scheduled to launch June 26, the IRIS spacecraft will point a telescope at the region of the sun called the chromosphere to look for signs of how energy moves from the sun's surface to the glowing corona, heating up from 6,000 degrees to millions of degrees in the process.
The IRIS mission, short for Interface Region Imaging Spectrograph, calls for the 7-foot-long spacecraft to point its ultraviolet telescope at the sun to discern features as small as 150 miles across. It will look at about 1 percent of the sun's surface.
"IRIS will show the solar chromosphere in more detail than has ever been observed before," said Adrian Daw, deputy project scientist. "My opinion is that we are bound to see something we didn't expect to see."
Scientists plan to combine the results of IRIS' surveys with the raft of information from NASA's Solar Dynamics Observatory, which observes the whole sun at once.
"IRIS almost acts as a microscope to SDO's telescope," said Jim Hall, NASA’s Launch Services Program’s mission manager for IRIS. "It's going to look in closely and it's going to look at that specific region to see how the changes in matter and energy occur in this region. It's going to collectively bring us a more complete view of the sun."
The answers are relevant to many aspects of life including the ways the sun's behavior helps dictate many elements of Earth's climate and weather patterns. Aberrations such as coronal mass ejections, commonly known as solar flares, also are of great interest to spacecraft designers who have to figure out ways to protect instruments and electronics from them.
"We're always looking for the answers to why and everything starts at the root with the sun," Hall said.
IRIS will ride into low Earth orbit on an Orbital Sciences Corp. Pegasus XL rocket. The Pegasus is famous as the only air-launch winged launcher in NASA's inventory. Though small compared to the gigantic boosters that send heavy satellites into orbit and probes to distant worlds, the Pegasus' size and flexibility has allowed numerous missions to be launched that would have been too small for larger rockets. The IRIS launch is the 42nd launch of the Pegasus. The last 27 missions, dating back to 1996, have been successful.
"Pegasus has been a tremendously successful launch vehicle for NASA," said Tim Dunn, NASA launch director for the IRIS mission. "We have launched 18 successful missions on Pegasus. The team is very dynamic, very flexible. They're able to accomplish a tremendous amount in a very short time."
The Pegasus and its IRIS payload will be carried to about 39,000 feet under Orbital’s “Stargazer” L-1011 carrier aircraft after taking off from Vandenberg Air Force Base in California. Flying over the Pacific Ocean off the California coast, the plane will release the Pegasus rocket to begin its flight into orbit.
The Pegasus will ignite its solid-fueled first stage five seconds into its fall and arch skyward with the main wing giving it lift and the three fins in the back steering it through the thick layers of Earth's lower atmosphere.
The rocket’s first stage will burn its load of fuel in 73 seconds and fall away. The second stage, which has no wings, will ignite 94 seconds into flight and push IRIS higher and faster into space. The third stage will take over after that, delivering IRIS into its orbit and separating from the rocket about 13 minutes after launch.
The launch is taking place from the West Coast because IRIS will go into a roughly polar orbit, meaning it will cross over the north and south pole regions of Earth on each pass around the planet.
"Eight months out of the year, we are freely viewing the sun in that orbit," Hall said.
Once IRIS is in space with its solar panels unfolded to provide electricity and the telescope flipped open, scientists expect to see intriguing data pretty quickly.
"I think the biggest surprise will come once the mission is launched and it starts to observe the sun," Daw said. "We know to some extent what we hope to learn, what specific science questions we are going to answer, but there's always that element of surprise."

Steven Siceloff,
NASA's Kennedy Space Center

Guillermo Gonzalo Sánchez Achutegui
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NASA - NASA Launches Satellite to Study How Sun's Atmosphere is Energized

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NASA's Voyager 1 Explores Final Frontier of Our 'Solar Bubble'
June 27, 2013
Artist concept of NASA's Voyager spacecraft. Image credit: NASA/JPL-Caltech
Artist concept of NASA's Voyager spacecraft.
Image Credit: 
PASADENA, Calif. -- Data from Voyager 1, now more than 11 billion miles (18 billion kilometers) from the sun, suggest the spacecraft is closer to becoming the first human-made object to reach interstellar space. Research using Voyager 1 data and published in the journal Science today provides new detail on the last region the spacecraft will cross before it leaves the heliosphere, or the bubble around our sun, and enters interstellar space. Three papers describe how Voyager 1's entry into a region called the magnetic highway resulted in simultaneous observations of the highest rate so far of charged particles from outside heliosphere and the disappearance of charged particles from inside the heliosphere.
Scientists have seen two of the three signs of interstellar arrival they expected to see: charged particles disappearing as they zoom out along the solar magnetic field, and cosmic rays from far outside zooming in. Scientists have not yet seen the third sign, an abrupt change in the direction of the magnetic field, which would indicate the presence of the interstellar magnetic field.
"This strange, last region before interstellar space is coming into focus, thanks to Voyager 1, humankind's most distant scout," said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. "If you looked at the cosmic ray and energetic particle data in isolation, you might think Voyager had reached interstellar space, but the team feels Voyager 1 has not yet gotten there because we are still within the domain of the sun's magnetic field."
Scientists do not know exactly how far Voyager 1 has to go to reach interstellar space. They estimate it could take several more months, or even years, to get there. The heliosphere extends at least 8 billion miles (13 billion kilometers) beyond all the planets in our solar system. It is dominated by the sun's magnetic field and an ionized wind expanding outward from the sun. Outside the heliosphere, interstellar space is filled with matter from other stars and the magnetic field present in the nearby region of the Milky Way.
Voyager 1 and its twin spacecraft, Voyager 2, were launched in 1977. They toured Jupiter, Saturn, Uranus and Neptune before embarking on their interstellar mission in 1990. They now aim to leave the heliosphere. Measuring the size of the heliosphere is part of the Voyagers' mission.
The Science papers focus on observations made from May to September 2012 by Voyager 1's cosmic ray, low-energy charged particle and magnetometer instruments, with some additional charged particle data obtained through April of this year.
Voyager 2 is about 9 billion miles (15 billion kilometers) from the sun and still inside the heliosphere. Voyager 1 was about 11 billion miles (18 billion kilometers) from the sun Aug. 25 when it reached the magnetic highway, also known as the depletion region, and a connection to interstellar space. This region allows charged particles to travel into and out of the heliosphere along a smooth magnetic field line, instead of bouncing around in all directions as if trapped on local roads. For the first time in this region, scientists could detect low-energy cosmic rays that originate from dying stars.
"We saw a dramatic and rapid disappearance of the solar-originating particles. They decreased in intensity by more than 1,000 times, as if there was a huge vacuum pump at the entrance ramp onto the magnetic highway," said Stamatios Krimigis, the low-energy charged particle instrument's principal investigator at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "We have never witnessed such a decrease before, except when Voyager 1 exited the giant magnetosphere of Jupiter, some 34 years ago."
Other charged particle behavior observed by Voyager 1 also indicates the spacecraft still is in a region of transition to the interstellar medium. While crossing into the new region, the charged particles originating from the heliosphere that decreased most quickly were those shooting straightest along solar magnetic field lines. Particles moving perpendicular to the magnetic field did not decrease as quickly. However, cosmic rays moving along the field lines in the magnetic highway region were somewhat more populous than those moving perpendicular to the field. In interstellar space, the direction of the moving charged particles is not expected to matter.
In the span of about 24 hours, the magnetic field originating from the sun also began piling up, like cars backed up on a freeway exit ramp. But scientists were able to quantify that the magnetic field barely changed direction -- by no more than 2 degrees. "
A day made such a difference in this region with the magnetic field suddenly doubling and becoming extraordinarily smooth," said Leonard Burlaga, the lead author of one of the papers, and based at NASA's Goddard Space Flight Center in Greenbelt, Md. "But since there was no significant change in the magnetic field direction, we're still observing the field lines originating at the sun."
NASA's Jet Propulsion Laboratory, in Pasadena, Calif., built and operates the Voyager spacecraft. California Institute of Technology in Pasadena manages JPL for NASA. The Voyager missions are a part of NASA's Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate at NASA Headquarters in Washington.
For more information about the Voyager spacecraft mission, visit:
 http://voyager.jpl.nasa.gov .
Jia-Rui C. Cook
Jet Propulsion Laboratory, Pasadena, Calif.
Steve Cole
NASA Headquarters, Washington
Guillermo Gonzalo Sánchez Achutegui
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NASA - Aircraft Carrying IRIS Solar Observatory Takes Off

Aircraft Carrying IRIS Solar Observatory Takes Off

An Orbital Sciences L-1011 carrier aircraft takes off from Vandenberg Air Force Base, Calif., on a mission to launch NASA's IRIS spacecraft into low-Earth orbit. IRIS, short for Interface Region Imaging Spectrograph, was launched on June 27, 2013 aboard an Orbital Sciences Pegasus XL rocket released from the L-1011.

IRIS is a NASA Small Explorer Mission to observe how solar material moves, gathers energy and heats up as it travels through a little-understood region in the sun's lower atmosphere. This interface region between the sun's photosphere and corona powers its dynamic million-degree atmosphere and drives the solar wind.

Photo Credit: VAFB/Chris Wiant
Guillermo Gonzalo Sánchez Achutegui
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NASA - Stargazer Aircraft Carrying IRIS Takes Off

Stargazer Aircraft Carrying IRIS Takes Off
The Orbital Sciences L-1011 aircraft takes off from Vandenberg Air Force Base in California at 9:30 p.m. EDT on June 27, 2013, headed over the Pacific Ocean to release the Pegasus XL rocket carrying NASA's Interface Region Imaging Spectrograph, or IRIS, solar observatory.
IRIS will open a new window of discovery using spectrometry and imaging to trace the flow of energy and plasma through the chromospheres and transition region into the sun’s corona. The spacecraft will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. This interface region, located between the sun's visible surface and its upper atmosphere, is where most of its ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate.
Photo Credit: NASA/Daniel Casper
Guillermo Gonzalo Sánchez Achutegui
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NASA - Nighttime Image of Texas Cities

 Nighttime Image of Texas Cities
One of the Expedition 36 crew members aboard the International Space Station, some 240 miles above Earth, used a 50mm lens to record this oblique nighttime image of a large part of the nation’s second largest state in area, including the four largest metropolitan areas in population. The extent of the metropolitan areas is easily visible at night due to city and highway lights.
The largest metro area, Dallas-Fort Worth, often referred to informally as the Metroplex, is the heavily cloud-covered area at the top center of the photo. Neighboring Oklahoma, on the north side of the Red River, less than 100 miles to the north of the Metroplex, appears to be experiencing thunderstorms. The Houston metropolitan area, including the coastal city of Galveston, is at lower right. To the east near the Texas border with Louisiana, the metropolitan area of Beaumont-Port Arthur appears as a smaller blotch of light, also hugging the coast of the Texas Gulf. Moving inland to the left side of the picture one can delineate the San Antonio metro area. The capital city of Austin can be seen to the northeast of San Antonio.
Guillermo Gonzalo Sánchez Achutegui

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NASA - Launch of NASA's New Solar Mission Rescheduled to June 27


The Pegasus rocket ignites to send NASA's IRIS spacecraft into orbit.
Image Credit: 
Image: NASA TV
NASA's Interface Region Imaging Spectrograph (IRIS) spacecraft launched at 10:27 p.m. EDT Wednesday from Vandenberg Air Force Base, Calif. The mission to study the solar atmosphere was placed in orbit by an Orbital Sciences Corporation Pegasus XL rocket. IRIS is a NASA Explorer Mission to observe how solar material moves, gathers energy and heats up as it travels through a little-understood region in the sun's lower atmosphere. This interface region between the sun's photosphere and corona powers its dynamic million-degree atmosphere and drives the solar wind. The interface region also is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. 
The Pegasus XL carrying IRIS was deployed from an Orbital L-1011 carrier aircraft over the Pacific Ocean at an altitude of 39,000 feet, off the central coast of California about 100 miles northwest of Vandenberg. The rocket placed IRIS into a sun-synchronous polar orbit that will allow it to make almost continuous solar observations during its two-year mission.

 Launch of NASA's New Solar Mission Rescheduled to June 27
WASHINGTON -- The launch of NASA's Interface Region Imaging Spectrograph (IRIS) mission is being delayed one day to 7:27 p.m. PDT (10:27 p.m. EDT) Thursday, June 27, from Vandenberg Air Force Base in California. Live NASA Television launch coverage begins at 6 p.m. PDT.

Because of a significant power outage at Vandenberg earlier this week, certain Western Range facilities will not be ready to support the original June 26 launch date. Range officials believe they will be able to restore power to the affected facilities in time to support a launch Thursday evening. Managers will assess the situation at the Launch Readiness Review Wednesday.

The launch of IRIS on an Orbital Sciences Corporation Pegasus XL rocket is targeted for the middle of a five-minute window.

IRIS is a NASA Small Explorer Mission to observe how solar material moves, gathers energy and heats up as it travels through a little-understood region in the sun's lower atmosphere. This interface region between the sun's photosphere and corona powers its dynamic million-degree atmosphere and drives the solar wind.

The drop of the air-launched Pegasus from Orbital's L-1011 carrier aircraft will occur over the Pacific Ocean at an altitude of 39,000 feet, about 100 miles northwest of Vandenberg off the central coast of California, south of Big Sur.

The IRIS News Center at Kennedy's Vandenberg Resident Office may be reached between 8 a.m. and 4:30 p.m. at 805-605-3051.

For complete details on media registration, media events, and live launch coverage on NASA TV, visit:

For NASA TV streaming video, schedule and downlink information, visit:

Extensive prelaunch and launch day coverage of the IRIS spacecraft will be available on NASA's home page at:

To view the IRIS webcast and launch blog, and learn more about the mission, visit:
Guillermo Gonzalo Sánchez Achutegui
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sábado, 29 de junio de 2013

nsf.gov : Ghosts of Forests Past: Bark Beetles Kill Lodgepole Pines, Affecting Entire Watersheds

Bark beetle epidemic changing water quality as well as forest health,
Mountain with dried trees in a forest overlooking Grand Lake, Colorado
Ghosts of a forest past: bark beetle-killed trees overlook Grand Lake, Colo.
Credit: Lindsay Bearup
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A stream going through bark beetle-felled trees
Bark beetle-felled trees fall, landing on a river and likely affecting the health of its waters.
Credit: Lindsay Bearup
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Scientists with soil and microbial samples beneath a beetle-killed tree.
Scientists take soil and microbial samples beneath a beetle-killed tree.
Credit: Thomas Cooper, Lightbox Images
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Beetle-killed trees line a river
Beetle-killed trees line a river; researchers have found water quality changes.
Credit: Lindsay Bearup
Download the high-resolution JPG version of the image. (4.4 MB)
Close-up of a pine with open areas in the bark created by beetle burrowing
Beetles burrowing into pines create open areas in the trees' bark.
Credit: Lindsay Bearup
Download the high-resolution 29 version of the image. (3.6 MB)
Researcher conducting experiments in a lab.
Researchers conduct experiments on the influence of chemicals in pine needles on soil.
Credit: Thomas Cooper, Lightbox Images
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The following is part eleven in a series on the National Science Foundation's Science, Engineering and Education for Sustainability (SEES) investment. Visit parts one, two, three, four, five, six, seven, eight, nine and ten in this series.
In mountains across the Western United States, scientists are racing against time--against a tiny beetle--to save the last lodgepole pines.
Forests are bleeding out from the effects of the beetles, their conifers' needles turning crimson before the trees die.
Now, researchers are also hurrying to preserve the region's water quality, affected by the deaths of the pines.
"When these trees die," says hydrologist Reed Maxwell of the Colorado School of Mines, "the loss of the forest canopy affects hydrology and the cycling of essential nutrients."
Maxwell and other scientists recently published results of their study in the journal Biogeochemistry.
Co-authors, in addition to Maxwell, are Kristin Mikkelson, Lindsay Bearup, John McCray and Jonathan Sharp of the Colorado School of Mines, and John Stednick of Colorado State University. Mikkelson is the paper's first author.

Bark beetle numbers: heating up
"The mountain pine beetle outbreak in Western states has reached epidemic proportions," says Maxwell.
Bark beetles, as they're known, are native to the United States. They're so-named as the beetles reproduce in the inner bark of trees. Some species, such as the mountain pine beetle, attack and kill live trees. Others live in dead, weakened or dying hosts.
Massive outbreaks of mountain pine beetles in western North America since the mid-2000s have felled millions of acres of forests from New Mexico to British Columbia, threatening increases in mudslides and wildfires.
Climate change could be to blame. The beetles' numbers were once kept in check by cold winter temperatures and trees that had plenty of water to use as a defense.
But winters have become warmer, and droughts have left trees water-stressed and less able to withstand an onslaught of winged invaders.
"A small change in temperature leads to a large change in the number of beetles--and now to a large change in water quality," says Tom Torgersen, director of the National Science Foundation's (NSF) Water, Sustainability and Climate (WSC) Program, which funded the research.
WSC is part of NSF's Science, Engineering and Education portfolio of investments.
"Bark beetles have killed 95 percent of mature lodgepole pines," says Maxwell.

Death of a lodgepole pine
But the trees don't die immediately.
When beetles invade, a blue fungus spreads inside a tree's trunk, choking off transpiration and killing the tree in about two years.
The trees turn blood-red, then the ashen gray of death, dropping their needles to the forest floor.
"Some of the most important effects of bark beetles may be changes in the hydrologic cycle," says Maxwell, "via snow accumulation under trees and water transpiration from trees and other plants."
Biogeochemical changes may be even more important, he says, with carbon and nitrogen cycles interrupted.
"We're studying these hydrologic and geochemical processes through a combination of field work, lab research and computer modeling," says Maxwell.

Whither the beetles, so the trees, forests...and waters
Changes in tree canopies affect snowpack development and snowmelt.
For example, a lack of needles on branches lets more snow fall through the canopy--snow that would otherwise be caught on branches. A tree without needles also has less shade beneath it.
The result is a shallower snowpack, earlier snowmelt and less water in spring.
"The real question," Maxwell says, "is how these processes translate from individual trees to hillslopes to large watersheds."
Dead trees don't transpire water. Once a forest has died, this important flow of moisture from the ground to the atmosphere ceases.
That can mean a loss of as much as 60 percent of the water budget, although increases in ground evaporation or transpiration from understory shrubs and bushes may compensate for some of the lack.
"Combined with what's happening to snowpack depth," says Maxwell, "it becomes a complicated relationship that can change the timing and magnitude of spring runoff from snowmelt--and an entire year's water resources."
Tree mortality also appears to affect forest carbon and nitrogen cycles through increases in dissolved organic carbon.
"We've seen changes in drinking water quality in beetle-affected watersheds that are almost certainly related to high dissolved organic carbon levels," says Maxwell.
As Maxwell, Mikkelson, Bearup and colleagues discovered, there's a lag time between beetle infestation and water quality declines, "so tree and forest water transport processes are very likely involved," says Maxwell.

All watersheds great and small

The observations prompted the researchers to study processes at the individual tree and hillslope scale to better understand what's happening in watersheds large and small.
"Watersheds are complex, interrelated systems," says Maxwell, "which makes understanding them more challenging.
"We're developing complex, numerical models of bark beetle-infested watersheds that include our best understanding of how and where water flows. The models are allowing us to isolate individual processes by turning them on and off in 'what-if' scenarios."
Along with on-the-ground observations, he says, "they're showing us more of the complex story of pine beetle effects on Western watersheds.
"We now know that healthy watersheds ultimately depend on healthy forests."
Western streams and rivers soon may be part of dead and dying forests, surrounded only by the ghosts of lodgepole pines past.

Related WebsitesNSF Science, Engineering and Education for Sustainability (SEES) Programs:
NSF "Discoveries in Sustainability" Publication:
NSF News Release: How Is Earth's Water System Linked With Land Use, Climate Change and Ecosystems?:  
Guillermo Gonzalo Sánchez Achutegui
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La Casa de la Loma tiene un Fantasma: Capítulo.- CCXVII.- Florentino "mano pesada" tiene amplio diálogo con el grupo de cinco aspirantes a bandoleros en Aragoto.

Hola amigos: A VUELO DE UN QUINDE EL BLOG., continuando con la historia de La Casa de la Loma tiene un Fantasma y como informamos en el capítulo anterior, Florentino "mano pesada" un solitario bandolero llegó a Aragoto y se hospedó en al casa de su primo Raimundo "Jefe", quien lo recibió muy bien por que ambos son bandoleros y tenían planes similares; la presencia de Florentino fue oportuna para integrarlo a los planes que tenía Raimundo y su grupo de realizar una incursión a la Hacienda "Loma feraz" en el Ecuador, lugar muy conocido por Florentino; los primos hicieron sus planes, al día siguiente llegaron los integrantes del grupo, justamente a la hora del desayuno.
Aquí en la imagen observamos una típica casa en la Comunidad Campesina de Socchabamba, Ayabaca, Piura, Perú; es una construcción de adobe con techo de tejas rojas y a dos aguas, sobre el techo distinguimos un fantasma que viene a ser el "El Rey de las Tinieblas" : Satanás, seguido de vampiros y una siniestra sombra negra que rodea al misterioso personaje satánico, para comprender la narrativa de la obra literaria: "LA CASA DE LA LOMA TIENE UN FANTASMA" , esta imagen será nuestro símbolo de identificación y el logotipo en creación, impresión y distribución literaria. Con reconocimiento de derechos de autor, con Partida Registral Nº 00393-2010, Asiento 01, con fecha 27 de marzo de 2010 por INDECOPI. Fuente de imagen: Archivos del blog .

Al llegar  los integrantes del grupo, Raimundo "jefe" uno a uno  fueron presentados a Florentino "mano pesada", luego de los saludos empezaron a conversar, naturalmente el más locuaz era Raimundo, quien se sentía protegido con la cooperación de Florentino y el diálogo era fluido; entonces,  Raimundo, le dijo a Abelardo "El tímido":
--- Oye, Abelardo creo que tus miedos se terminaron, porque mi primo Florentino ya es un hombre experimentado en incursiones y nos asegura que la Hacienda "Loma feraz" está llena de caudales esperándonos para apropiarnos de ellos.
Abelardo "el tímido", en realidad no lo era tal, sino que tomaba en cuenta todas las posibles riesgos y calamidades que podrían presentarse en una acción; como una incursión siempre es riesgosa por reacción de la víctima que en muchos casos se convertía en victimario defendiendo sus propiedades con su legítimo derecho; entonces Abelardo, contestó:
--- Mucho gusto conocerlo señor Florentino, celebro su presencia y le cuento que estamos empeñados en fingir de bandoleros sin haber hecho nada parecido antes, y si  usted es un experimentado bandolero, ¿ porqué ha venido a Aragoto completamente solo y sin fortuna?
Florentino, sintió un estremezón en todo su cuerpo por que el "muchachito" le dijo toda la verdad, por que nada tenía, solamente sabía usar la "mano pesada" y nada más, y como había más gente, se vio en la necesidad de contestar tan incómoda y malcriado pregunta......
--- Caramba Abelardo, tu si que sabes ofender a los amigos y yo no estoy aquí  buscando fortuna, viajaré hasta Cujaca, si es que ustedes no desean que los acompañe al Ecuador y si me quedo es por una invitación de mi primo Raimundo; además, es mi costumbre caminar sólo que mal acompañado. por que en las acciones decisivas te traicionan clavándote la chaveta por la espalda.
Entonces, intervino Isidro "bocón" para apaciguar al recién llegado, diciéndole:
--- Amigo Florentino, no tiene por que enojarse, nosotros aún no hemos hecho una acción como la que pretendemos hacer en el Ecuador; si usted es un viejo asaltante, sus enseñanzas serán valiosas para nosotros y desde mi humilde persona le doy la bienvenida y si no es pedir mucho le ruego, nos entrene en el manejo de armas y lo principal; ¿Cómo debemos viajar a la Casa Hacienda que vamos asaltar?
Florentino, se dio un sacudón de hombros y la pregunta dio en la yema del gusto y entendió que se estaba interesando su presencia ante los muchachos; haciendo los ademanes de un padre a su prole, le contestó:
--- Hijos, el arte de asaltar a un adinerado es de mucha paciencia, haciéndole un seguimiento noche y día y a la vez analizando la parte débil que cualquier persona la tenemos, al llegar a ese momento se ataca y con ventaja por que la reacción de la víctima será nula.
Florentino, hizo una pausa y mirando a los aprendices de bandoleros, prosiguió:
--- Algunos de ustedes han visto cazar a un zorro a la gallina, el cazador cuando detectó a la presa  se esconde y de rato en rato saca la cabeza acercándose cada vez más y más y cuando ubico el grupo de gallinas con gallo y todo  a su alcance que están raspando la tierra  buscando gusanitos en los campos fuera de la casa, el zorro siempre se ubica a la cabecera o al final del campo y va arrastrando su cuerpo hasta llegar a una distancia que con un salto le permita atrapar a la gallina y cuando caza nunca falla
Florentino, nuevamente toma una pausa y agregó:
--- La caza de la gallina por el zorro es exactamente como nosotros tenemos que hacer a la Casa Hacienda, con la diferencia que atacamos en la noche, cuando la gente duerme o está tan cansada  que están con la guardia baja y la hora más precisa es entre las 24:00 de la noche hasta las 3:00 de la mañana.
Nuevamente el "instructor" descansa y finaliza:
--- Antes de asaltar, se estudia la parte débil de la casa y los protectores (vigilantes), e igualmente los puntos de escape luego del asalto y cuando todo lo preparado está listo, se grita a viva voz que lo están asaltando, anticipándoles que no opongan resistencia por que si lo hacen serán muertos, lo que se pretende es asustar a la víctima, en otras palabras : Robarle el espíritu y cuando se logra, ellos colaboran mostrando el escondite de los entierros en donde han metido los caudales o los tesoros.
Los cincos muchachos incluido el dueño de casa, se habían quedado mudos escuchando las expresiones que hacía Florentino; entonces, intervino Miguel "cara chueca" y dijo:
--- Caramba Don Florentino, usted si sabe actuar como un astuto zorro, por lo que he escuchado me parece fácil asaltar a una Hacienda, pero hay algo que me preocupa, si nosotros vamos por primera vez a esa Hacienda, no conocemos nada de los puntos débiles, ni la gente que la protege a la hacienda; tampoco sabemos si tienen guardianes armados con carabinas, nadie de nosotros ha viajado antes a conocer el terreno que vamos a pisar.
Florentino, esperaba esas expresiones de preocupación y para vanagloriarse ser el guía, le contestó:
--- Mis queridos amigos, para eso me tienen a mi, yo si conozco el terreno que vamos a pisar y sobretodo a sacar fortuna para hacernos ricos, esta es la oportunidad de su vida y será el inicio de muchas incursiones más y lo importante se bautizarán con la única experiencia acompañados por mi persona.
Hubo un murmullo entre los jóvenes aspirantes a bandoleros y uno de ellos, Candelario "el suertudo", le dijo:
--- ¿Cómo sabe usted que hay muchos caudales allí?

Florentino, movió los hombros  muy ufano y tal vez soberbio y le contestó:
--- Escúchame jovencito, en la hacienda hay muchos tesoros, pero no soy Dios para anticipar  cuantos caudales hay, si quieres saberlo tendrás que ir tu mismo y averiguarlo, pero te aseguro que si vas conmigo no te arrepentirás de haber nacido
Los jóvenes volvieron a murmurar entre ellos, pero intervino Raimundo, diciéndoles:
--- Muchachos, ya han conversado lo suficiente con mi primo Florentino y como él, les dijo, yo lo invité y será nuestro guía hacia el Ecuador, por ahora los invito a desayunar  y luego seguiremos con los entrenamientos, con la diferencia que hoy tenemos a un viejo zorro que nos enseñará sus secretos..... continuaremos......
Guillermo Gonzalo Sánchez Achutegui

La Historia del Amor Cruel: Capítulo CVIII.- Mientras Olzagon comparte muy feliz con Laurita, Don Santiago tiene una pesadilla de perder clientes por capricho de su hija, exigiendo despida al empeñoso vendedor

Hola amigos: A VUELO DE UN QUINDE EL BLOG., continuando con La Historia del Amor Cruel entre Iarma y Olzagon y como informamos en el capítulo anterior, Olzagon debutó brillantemente como vendedor en la Feria de Productos Industriales , Cosmético y Diversos del Distrito "La Esmeralda", representando a la Fábrica de Productos Plásticos "El Ideal" que promocionaba su producto: Bolsas Plástico con Asa (chequeras) una innovación industrial en los años 1,970s; si bien el primer día se hicieron ventas pequeñas, se estableció contactos para un gran pedido en los próximos días; igualmente Olzagon sugirió obsequiar a los clientes una pequeña bolsa chequera con una golosina adentro, algo que no le pareció bien a Pamela y al retirarse de la Feria, llegó muy enojada a su casa y exigió a su madre que le pida a su padre que despida al vendedor Olzagon.
 Aquí en la imagen observamos una típica representación de la terrible situación que muchos hogares atraviesan en el transcurso de existencia por que siempre hay la existencia de un tercer elemento (amante tanto para él como para ella) que como una tentación tenebrosa carcomen la consistencia del matrimonio, y más si los esposos viven solamente la apariencia y no la triste realidad de que no son felices. Fuente: Archivos del blog. Obra Literaria reconocida con Derecho de Autor, según Partida Registral No. 00855-2012, Asiento: 01; con fecha: 10 de Agosto de 2012, por : INDECOPI.

Pamela, sufría de celos por competencia, que siendo la hija  consentida de Don Santiago, con la presencia del vendedor Olzagon se sentía desplazada, dado el protagonismo del joven, quien haciendo uso de su innato "Don de ventas" trataba de promocionar las Bolsas Plásticas con Asa (chequeras), en todo sentido de la palabra eran incomprensibles los enojos de Pamela.
Olzagon, fue específicamente contratado para promocionar el uso de las Bolsas Plásticas y como tenía experiencia en la venta directa al consumidor final, se afianzaba en ese lado para influir a los visitantes a la Feria, explicando las bondades por el uso de Bolsas Plásticas con Asa y por esa razón tenía que demostrar su capacidad y justificar la razón de su contratación.
Don Santiago, quien era un empresario innovador y dueño de una poderosa fábrica, él; constantemente viajaba al extranjero para cerciorarse de primera mano los últimos adelantos en el  uso del plástico y viendo en Europa la infinidad de productos derivados del uso de esta materia prima en el bien del consumidor; aplicó sus conocimientos en el diseño de nuevos productos utilizando el plástico y vaya que acertaba por que lo producido era aceptado por el consumidor.
Don Santiago, lleno de muchas satisfacciones, salió del Campo Ferial y después de despedirse de Olzagon, se dirigió a su domicilio y llegó pasadas las 23:40 horas del día y encontró a su esposa muy preocupada, pues le preguntó:
--- Amor mío, ¿por qué me recibes con esa cara de pocos amigos? justamente con el vendedor acabamos de cerrar el stand y directo he venido a  la casa.
La señora con una sonrisa abrazó amorosamente a su esposo y le contestó:
--- No seas tonto, nada tengo contra ti, es tu hija la que llegó con todos los demonios adentro en su cuerpo, ya que según ella, tu has contratado a un joven vendedor que ella no lo acepta por presumido y me pidió que te diga, que si quieres que ella siga en la Feria tienes que despedir al "antipático vendedor".
Don Santiago se rascó la cabeza y entendió los celos de su hija Pamela, quien se sentía desplazada, y todo era infundado, por que él joven vendedor Olzagon se le contrató para trabajar a tiempo completo en la promoción del nuevo producto y le contestó a su esposa, así:
--- Aayyy, esposa mía, nuestra hija sigue comportándose como una adolescente, ella ya es profesional y con avanzados estudios de Mercadotecnia; en cambio en el joven Olzagon, aún era un aspirante a ingresar a una Universidad Pública, si no es que él, tiene un "don de llegar al consumidor" y eso no se estudia en la Academia, con dolor de mi corazón, pero esta vez no le voy a dar gusto a su capricho, por que yo necesito al joven vendedor y él, me ha demostrado que sabe hacer su trabajo.
La señora siempre apegada a los caprichos de la hija, viendo a su esposo el semblante decidido, le contestó:
--- Amado esposo, es nuestra única hija y según ella se da a vasto para influir en los gerentes y empresarios para colocar  tus productos, y si ahora se siente mal con ese joven, no podremos salir adelante con esas ventas; en fin yo no conozco mucho de negocios, pero si estoy segura que ella está vinculada a los empresarios mayoristas, que tan solo convenciendo a uno de ellos te compraría la producción de un año; que te parece si tanto tienes Fe en ese joven, sácalo de la Feria y envíalo a vender al Mercado Mayorista, allí encontrará a cientos de comerciantes que pueden comprar tu producto.
Don Santiago amaba demasiado a su esposa y adoraba  a su engreída Pamela y por primera vez se encontraba en una encrucijada : ceder al capricho de su hija o mantenerse en su decisión empresarial con el compromiso asumido con Olzagon en bien de la Fábrica.
Por otro lado, Olzagon llegó a su casa muy feliz en haber hecho cosas buenas en su primer día de trabajo para la Fábrica de Productos Plásticos "El Ideal" y ya había establecido sus primeros contactos comerciales con potenciales clientes que lo harían triunfar en su trabajo, fue recibido por Laurita, quien lo había esperado siendo ya las 11:45 horas (23:45 horas) del día con la comida caliente, como nadie más estaba a esas horas, ellos se abrazaron y se besaron amorosamente y ella sentía la felicidad de su joven amante y le preguntó:
--- ¿Cómo te fue en tu primer día de trabajo en esa fábrica?
Él, le respondió con un ardiente beso y agregó:
--- Muy bien, todo salió a las mil maravillas, imagínate que el bodeguero de la esquina (Don Emilio) nos comprará mañana muchas bolsas plásticas con asa.
Laurita un poco intrigada y volvió a preguntar:
--- ¡¡¡ que vendes bolsas plásticas con asa !!! y que Don Emilio te comprará, ¿ cómo son esas bolsas plásticas?
Olzagon con una mirada tierna y amorosa, le contestó:
--- Laurita,  tu compras tus comestibles con bolsas de papel y tienes que marcarlas (abrazarlas) cuando están completamente llenas y no puedes llevar más que dos  y con dificultad y peligro de que se rompan y se caigan todas las cosas de su contenido; entonces, con el uso del plástico se ha creado Bolsas Plásticas con Asa, que te permiten llevar más cosas y las llevas colgadas las bolsas de las asas completamente llenas y puedes llevar dos, tres o cuatro al mismo tiempo hasta donde te alcancen tus dedos  y el peso que puedes soportar y son más resistentes que el papel, tal vez lo más importante viene en diferentes medidas desde una pequeña para medio kilo de azúcar hasta otras de 50 kilos de capacidad.
Laurita, se había quedado escuchando a su amante con la boca abierta y lo más que le llamaba la atención era la seguridad  total del convencimiento como lo expresaba las bondades para el uso de esas bolsas plásticas.
Luego los amantes, fueron a la sala y como había un sillón-cómoda, que más parecía un colchón y dieron rienda suelta a un encuentro amoroso, nadie los interrumpió, por que todos dormían ya eran las 24:00 horas del día, terminada la función...!!! .. él, la llevó en vilo a su cama y durmieron amorosamente.
En la otra casa, Don Santiago, sin tomar una decisión no prevista por las exigencias de su esposa, se fue junto a ella al dormitorio y después de tiernas caricias se acostaron, rápidamente conciliaron el sueño y en ese profundo descanso, Don Santiago, tuvo un sueño: Una visita de un gran comerciante que buscaba al joven vendedor Olzagon, para pedirle 10 toneladas de bolsas plásticas y Don Santiago le informó que le vendedor fue despedido y que él personalmente le atendería por ser el dueño y fabricante; entonces, el cliente le contestó:
--- "Señor, usted  es una mala persona, por haber despedido a su mejor vendedor y por esa razón anulo el pedido y ese dinero que traía lo invertirá en otras mercaderías".
Don Santiago, hizo un ademán de insistir en la atención, diciéndole al cliente:
--- "Olzagon se fue por que mi hija no lo quiere como su ayudante"
El cliente, bastante enojado, le contestó:
--- "Caramba, que poca capacidad de hombre tiene usted, cede a los caprichos de hijita y pierde ventas muy importantes a clientes como yo, pues con usted no se puede hacer negocios, me voy y si en algún momento regresa ese joven, puedo pensar de nuevo en mi pedido"
Don Santiago, se despertó, eran las 3:00 de la madrugada y dio un suspiro de alivio por que todo había sido una pesadilla, su esposa dormía plácidamente, pero él, ya no pudo conciliar el sueño y pasaron por su mente tantas ideas y un pensamiento funesto: "si todo lo soñado se hace realidad más tarde"....... continuaremos.....
Guillermo Gonzalo Sánchez Achutegui

jueves, 27 de junio de 2013

Rascacielos: El Empire State Building recibe dos multimillonarias ofertas de compra

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El edificio Empire State (en inglés: Empire State Building) es un rascacielos situado en la intersección de la Quinta Avenida y West 34th Street, en la ciudad de Nueva York, Estados Unidos. Su nombre deriva del apodo del Estado de Nueva York. Fue el edificio más alto del mundo durante más de cuarenta años, desde su finalización en 1931 hasta 1972, año en que se completó la construcción de la torre norte del World Trade Center. Tras la destrucción del World Trade Center el 11 de septiembre de 2001, el edificio Empire State se convirtió nuevamente en el edificio más alto de la ciudad de Nueva York y del estado de Nueva York, hasta que fue otra vez traspasado por One World Trade Center el 30 de abril de 2012 como la torre más alta de Nueva York, quedando el Empire State en segundo lugar.1
El edificio Empire State ha sido nombrado por la Sociedad Estadounidense de Ingenieros Civiles como una de las Siete Maravillas del mundo moderno. El edificio y su interior son designados monumentos de la Comisión para la Preservación de Monumentos Históricos de Nueva York, y confirmado por la Junta de Estimación de la Ciudad de Nueva York. Fue designado como un monumento Histórico Nacional en 1986. En 2007, ocupó el número uno en la lista de las edificaciones favoritas americanas y hoy día también. El edificio es propiedad y está gestionado por W & H Properties.

El Empire State Building recibe dos multimillonarias ofertas de compra

El Empire State Building recibe dos multimillonarias ofertas de compra
Nueva York, 27 jun (EFE).- Los propietarios del Empire State Building de Nueva York han recibido dos ofertas de compra por el emblemático rascacielos, una por 2.000 millones de dólares y otra por 2.100 millones.
En un documento que se puede ver hoy en la web de la Comisión del Mercado de Valores de EE.UU., la familia Malkin, que controla el histórico inmueble, anunció que la semana pasada recibió dos propuestas de adquisición no solicitadas, aunque no detalla de quién provienen.
"Consideramos todas las opciones, incluyendo las ofertas no solicitadas", dice el documento que firman Peter y Anthony Malkin, aunque aseguran que no responderán a estas propuestas hasta que no sean analizadas.
Los Malkin han impulsado un proyecto para agrupar el rascacielos junto a otra veintena de edificios en una nueva empresa que concentre los derechos de propiedad, un fondo de inversión en bienes raíces llamado Empire State Realty Trust, y sacar esa firma a bolsa.
Tras haberse encontrado con la oposición inicial de un grupo de pequeños inversores que incluso llegó a los tribunales de Nueva York, el proyecto consiguió a finales de mayo la mayoría necesaria de votos para salir adelante y convertir el Empire State en una empresa cotizada.
Estas dos nuevas ofertas podrían evitar ese plan, aunque ninguna de ellas alcanza los alrededor de 2.500 millones de dólares a los que valoran los Malkin el famoso rascacielos neoyorquino.
Según publica hoy el diario The New York Post, detrás de la oferta de 2.100 millones está un inversor de Oriente Medio que se ha aliado con los promotores inmobiliarios estadounidenses Joe Tabak, de Princeton Holdings, y Philip Pilevsky, de Philips International.
Rubin Schron, un inversor en bienes raíces de Nueva York, estaría detrás de la otra propuesta de adquisición.
El famoso Empire State Building, de 102 pisos y situado en la Quinta Avenida a la altura de la calle 34 de Manhattan, recibe cada año unos cuatro millones de visitantes, que ascienden a lo más alto del rascacielos para contemplar desde allí las vistas de la Gran Manzana.
Guillermo Gonzalo Sánchez Achutegui
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