Wednesday, December 29, 2010

GLOWING MUSHROOM : Psychedelic New Species Seen


Glowing nonstop in the Brazilian rain forest, the newfound mushroom Mycena luxaeterna (pictured both in daylight, top, and in the dark) is indeed a source of eternal light, as its Latin name--inspired by verses from Mozart's "Requiem"--implies.

The tiny mushroom is one of 7 new species of glow-in-the-dark fungi found around the world, bringing the total known to 71, according to a study that appeared October 5 in the journal Mycologia.

San Francisco State University's Dennis Desjardin and colleagues scouted for mushrooms during new moons, in rain forests so dark they often couldn't see their hands in front of their faces, he said.

But "when you look down at the ground, it's like looking up at the sky," Desjardin said. "Every little 'star' was a little mushroom--it was just fantastic."

M. luxaeterna has a distinctive sticky gel on its stem that probably keeps it moist during the heat of the day. Unwitting insects get trapped in this natural fly paper, said Desjardin, who discovered the fungi with the University of Sao Paulo's Cassius V. Stevani.

Desjardin's colleague, Timothy Baroni of the State University of New York at Cortland, received funding to research the mushrooms from the National Geographic Society. (The National Geographic Society owns National Geographic News.)


--Christine Dell'Amore
—Photograph courtesy Cassius V. Stevani, Chemistry Institute, University of Sao Paulo


nationalgeographic.com

Monday, December 27, 2010

Motocross Biker, Colorado


Photograph by Rayner Marx, My Shot
This Month in Photo of the Day: Travel and Adventure Photos
Track owner Donnie Burns hurls into a dark heaven at Wild Rat Motocross in Colorado Springs, Colorado.

nationalgeographic.com

Solenostemon scutellarioides

Scientific classification
Kingdom : Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order : Lamiales
Family : Lamiaceae
Genus : Solenostemon
Species : S. scutellarioides
Binomial name
Solenostemon scutellarioides
Synonyms
* Coleus blumei Benth.
* Coleus blumei var. verschaffeltii (Lem.) Lem.
* Coleus hybridus hort. ex Voss
* Coleus pumilus Blancoright
* Coleus scutellarioides (L.) Benth.
* Coleus verschaffeltii Lem.
* Ocimum scutellarioides L.
* Plectranthus scutellarioides (L.) R. Br.

The Coleus plant has very colorful foliage and is popular as a houseplant and in gardens. Its geographic origin is Southeast Asia and Malaysia. The plant has various names, including "Coleus blumei".
The Coleus are very easy to propagate by cuttings, and they like partial shade, though can stand a bit of direct sunlight. They are not frost tolerant.




wikipedia.com

Parasitism of Cuscuta

After a dodder attaches itself to a plant, it wraps itself around it. If the host contains food beneficial to dodder, the dodder produces haustoria that insert themselves into the vascular system of the host. The original root of the dodder in the soil then dies. The dodder can grow and attach itself to multiple plants. In tropical areas it can grow more or less continuously, and may reach high into the canopy of shrubs and trees; in temperate regions it is an annual plant and is restricted to relatively low vegetation that can be reached by new seedlings each spring.

Dodder is parasitic on a very wide variety of plants, including a number of agricultural and horticultural crop species, such as alfalfa, lespedeza, flax, clover, potatoes, chrysanthemum, dahlia, helenium, trumpet vine, ivy and petunias, among others.

Dodder ranges in severity based on its species and the species of the host, the time of attack, and whether any viruses are also present in the host plant. By debilitating the host plant, dodder decreases the ability of plants to resist virus diseases, and dodder can also spread plant diseases from one host to another if it is attached to more than one plant.




wikipedia.com

Thursday, December 23, 2010

Evolutionary relationships among major groups of cetaceans


Pictured: Mesonychidae, Pakicetidae, Ambulocetidae, Remingtonocetidae, Protocetidae, Dorundontidae, Basilosauridae, Mysticetes, Odontocetes

Geologic age: Modern

karencarr.com

Evolutionary chart of relationships between tetrapods‚ leading to split to Amniota


Geologic age: Modern

Description: Evolutionary chart of relationships between tetrapods‚ leading to split to Amniota

karencarr.com

Conocoryphe sulzeri


Conocoryphe sulzeri, Jince formation, Czechoslovakia. Pete Lawrance collection. Although eyes are normally an extremely important survival feature, there are situations under which loss of eyes might occur. For example, trilobites that took advantage of deep-water benthic (bottom-feeding) habitats where light was dim or lacking might have gradually lost their eyes without suffering an adaptive disadvantage. Such eyeless trilobite assemblages are called atheloptic.

micromacro.co.uk

Mortoniceras




Pictured: Mortoniceras
Geologic age: Cretaceous

karencarr.com

Hydrologic Cycle


Water is the source of all life on earth. The distribution of water, however, is quite varied; many locations have plenty of it while others have very little. Water exists on earth as a solid (ice), liquid or gas (water vapor). Oceans, rivers, clouds, and rain, all of which contain water, are in a frequent state of change (surface water evaporates, cloud water precipitates, rainfall infiltrates the ground, etc.). However, the total amount of the earth's water does not change. The circulation and conservation of earth's water is called the "hydrologic cycle".

image from karencarr.com

Thursday, December 16, 2010

Integral ln x dx



Strategy: Use Integration by Parts.
ln(x) dx

set
u = ln(x), dv = dx
then we find
du = (1/x) dx, v = x

substitute

ln(x) dx = u dv

and use integration by parts

= uv - v du

substitute u=ln(x), v=x, and du=(1/x)dx

= ln(x) x - x (1/x) dx
= ln(x) x - dx
= ln(x) x - x + C
= x ln(x) - x + C.

Monday, December 13, 2010

Solar Snake



Image courtesy SDO/NASA

A long loop of plasma that had been snaking around the sun erupted on Monday, and NASA's Solar Dynamics Observatory was on hand to catch the action.
Known as a solar filament, the loop is a cloud of relatively cool gas held aloft by magnetic forces. Such features are unstable, though, and often break away from the sun.
The pictured filament grew extra long, according to NASA: It spanned almost 621,000 miles (a million kilometers) before snapping.

nationalgeographic.com

New Chemistry, Less Energy Could Yield Greener Cement


A factory in southwest China's Sichuan province for making cement, among the most carbon-intensive industrial processes. German researchers have made a breakthrough in reducing emissions, in part by using special silicon materials like the one below, characterized by its flower-like crystals.

Chemicals in Apple Skins, Wine Could Help Fight Alzheimer's


A type of chemical derived from curry, wine and apple skins may help protect nerve cells from Alzheimer's.


Supplements derived from apple skins, red wine and tumeric might someday help slow the onset and progression of Alzheimer's and related diseases, according to accumulating evidence.
The details are complicated and still a matter of debate. But the scientists involved are basing their strategy on what they say is a new way of thinking about Alzheimer's.
In their view, a group of chemicals called type-2 alkenes, which are widespread in both the environment and the brains of Alzheimer's patients, act as major drivers of the disease. In turn, said chemical neurotoxicologist Richard LoPachin, neutraceuticals of the future could stop these brain-damaging chemicals in their tracks.
Already, LoPachin's group has developed just such a compound that, in Petri dishes at least, sops up type-2 alkenes and protects nerves from harm.
"If you talk to someone else, they may tell you I'm nuts," said LoPachin, of the Montefiore Medical Center in Bronx, New York. "We know that humans are pervasively exposed to type-2 alkenes, but nobody has ever considered the possibility that type-2 alkenes in the environment might be involved in Alzheimer's. It's a new theory of Alzheimer's."
Alzheimer's is a multi-faceted disease and efforts to understand it have followed a variety of paths. One line of research focuses on the endings of nerve cells in the brain, which degenerate as the disease progresses.
When that happens, communication among nuerons breaks down, leading to confusion, forgetfulness and other hallmark symptoms of Alzheimer's.
While scientists disagree about what causes nerve-ending degeneration, studies have clearly shown that the progression of the disease itself produces type-2 alkenes in the brain. Chemicals in this group, such as acrylamide and methylvinyl ketone, also show up in car exhaust, cigarette smoke, industrial settings, even French fries.
Exposure to type-2 alkenes in the environment has already been linked with cancer, heart disease, and other problems. For Alzheimer's patients, LoPachin argues, the double whammy of exposure from both within the brain and from out in the environment could accelerate the onset and progression of the disease.
As evidence, he points to studies showing that Alzheimer's patients have large amounts of type-2 alkenes in their brains. The chemicals appear to selectively target the ends of nerve cells, which are highly vulnerable to damage. And cigarette smoking increases the risk of Alzheimer's by more than 150 percent, possibly because of the type-2 alkenes in tobacco smoke.
If LoPachin is right, then mopping up type-2 alkenes in the brain should help fight Alzheimer's as well as other problems, such as Parkinson's, spinal cord injuries, and strokes. In a new paper in the Journal of Neurochemistry, LoPachin and colleagues report the development of just such an antidote.
The researchers drew inspiration from a group of well-studied chemicals made by some plants, including resveratrol in grapes, curcumin in tumeric, and phloretin in apple skins. These compounds, which are all similar in chemical structure, have promising characteristics, but the human body does not easily absorb them, and they can be toxic at very high doses.
Instead, the researchers used the structure of these natural plant compounds to develop a new chemical, called 2-ACP.
In their lab studies, 2-ACP latched onto a type-2 alkene called acrolein and prevented the toxin from damaging nerve cells.
Years of testing -- first in animals, then people -- await the new molecule, LoPachin said. But he thinks the research is an important step in the battle against Alzheimer's.
Other experts are more cautious. Neutralizing type-2 alkenes in the brain will likely be a good strategy for fighting Alzheimer's, said D. Allan Butterfield, a biological chemist at the University of Kentucky, Lexington. And the new study confirms many details that other studies have already showed.
But he disagreed with the argument that type-2 alkenes in the environment are part of the story.
"There's no evidence at all that these cause Alzheimer's," Butterfield said. "I'm an expert on Alzheimer's. I can't claim to say they might not be important in something like cancer. I don't know. But in Alzheimer's, I'm convinced that's not the case."
He also questioned the practicality of a supplement like the kind that LoPachin and colleagues are working on. At this point, he said, the doses in question are far too high to be safe for people.
"If you slowly increase the concentration of molecules like curcumin, you find ever increasing benefits, but at some point, there is a very sharp decline such that there is horrendous harm," Butterfield said. "The therapeutic level and the harmful level may not be that far apart from each other. One would have to be very, very careful."


news.discovery.com

Climate Change Threatens Archaeological Treasures


Melting ice can help unlock ancient secrets, but warming temperatures could imperil many more historic sites.


Mummies decaying in Siberia, pyramids vanishing under the sand in Sudan, Maya temples collapsing: Climate change risks destroying countless treasures from our shared past, archaeologists warn.
Melting ice can unlock ancient secrets from the ground, as with the discovery in 1991 of "Oetzi", a 5,300-year-old warrior whose body had been preserved through the millennia inside an Alpine glacier.
But as ice caps melt, deserts spread, ocean levels rise and hurricanes intensify -- all forecast effects of man-made global warming -- Henri-Paul Francfort of the CNRS research institute fears a heavy toll on world heritage.
Francfort is head of a French archaeological team in Central Asia that played an important part in excavating the Kurgans, or frozen tombs, of nomadic Scythian tribes in Siberia's Altai mountains.
He fears they now risk being lost.
"The permafrost, the constantly frozen layer of earth that protected them up until now, is melting," he said. "There are mummified, tattooed bodies, buried with sacrificed horses, furs, wooden objects and clothes."
"With my Russian colleagues, we are watching the part of the soil that melts each season, and which is getting deeper and deeper," he added. "Unless we take preventative action, it will soon be too late."
According to Francfort, Oetzi's remains were most certainly uncovered due to a receding high-altitude glacier in the Italian Tyrol region.
"Melting glaciers, especially in Norway, now regularly reveal other treasures," he said.
Like a modern-day Atlantis, experts warn that rising ocean levels -- which some forecast could jump a meter (three feet) by 2100 -- stand to wipe out dozens of coastal archaeological sites, with Pacific islands on the frontline.
In Tanzania, maritime erosion has already destroyed a wall of the Kilwa fort, built by Portuguese colonialists on an island just off the coast in 1505, Francfort said.
And in Bangladesh, the ruined city of Panam in Sonargaon, the heart of the kingdom of Bengal from the 15th to 19th centuries, is regularly hit by flooding.
Today, Panam is one of 100 sites listed by the UN culture agency UNESCO as threatened by climate change.
A forecast spike in unpredictable weather events -- hurricanes chief among them -- is another major source of concern, says Dominique Michelet, a specialist of American archaeology at the CNRS.
He cites the case of Chan Chan in Peru, former capital of the Chimu civilisation and the largest pre-Colombian city in Latin America, which is already severely exposed to flooding linked to the El Nino weather pattern.
Likewise, the Maya temple of Tabasqueno in Mexico had to be largely rebuilt after it was badly damaged by two tornadoes -- Opalo and Roxana -- in 1995.
"Archaeologists had managed to stabilize the main temple, but the buildings became saturated with water and collapsed inward," Michelet said.
Sand is one of the worst enemies of archaeological sites, like in Sudan where dunes are encroaching on the burial pyramids of Meroe, the capital of a flourishing kingdom from the third century B.C. to the fourth A.D.
"In Oman, two cyclones -- Gonu un 2007 and Phet last year -- totally buried in sand sites that date back to the fifth and sixth millennia B.C.," said Vincent Charpentier, of the INRAP archaeological research center.
Michelet warns that UNESCO's efforts so far to identify at-risk sites do not go far enough, calling for the world to "sound the alert" over the threat.
"Archaeology is part of human memory," said Francfort, who suggests radical solutions may be needed to protect past treasures from climate change, citing the case of the Abu Simbel rock temples in Egypt.
Following a concerted international effort, the entire complex was relocated in the 1960s to prevent them being submerged by the building of a dam on the River Nile.

news.discovery.com

Thursday, December 02, 2010

Triassic Fish


Photograph by O. Louis Mazzatenta

This Triassic-era fish is among the thousands of fossils uncovered in the mountains and karst formations of China's Guizhou Province. Much of this region was under a shallow ocean during the Triassic period, and sediments there teem with the ancient remains of fish, dinosaurs, and marine reptiles.

nationalgeographic.com