Monday, December 24, 2012

Tricky spiders' web and 33 new species of trapdoor spider

Cobwebs are actually small feats of engineering.  Polymer scientists at the University of Akron have discovered that the common house spider can tailor the type of adhesive discs it uses to anchor its webs, making them stronger or weaker depending on where the cobwebs are situated and the anticipated movements of its prey.
Webs located up in the air, such as those on ceilings and vertical surfaces, tend to catch flying insects, which are moving at a greater velocity.  So the adhesive used in these is stronger – that way the web doesn’t come loose when it’s struck by an airborne object moving at a high rate of speed.  But when spiders build webs that are located close to the ground, they use less adhesive in the discs.  When an unsuspecting insect wanders into a web, the anchoring thread snaps away from the ground and – voila! – the spider’s dinner is left dangling helplessly in the air by a sticky silk strand.

The polymer experts were impressed by the sophistication of this trick.  “What we have also discovered is a key design principle,” said Ph.D graduate Vasav Sahni. “It’s not a question of the inherent chemistry of the glue, but how the same glue can have different degrees of adhesion.”

The Akron team have published the details of their study in the most recent issue of Nature Communications.


The discovery of 33 new species of sneaky trapdoor spiders boosts the total number described in one genus from seven species to 40.

Trapdoor spiders, which belong to the same suborder as tarantulas, are pretty badass. Instead of weaving webs, they build subterranean silk-lined burrows — and cap the burrow with a trapdoor. Then, hunkered down beneath the trap door, the spiders wait for an unsuspecting insect to trigger the trip lines.

“They’re sort of ambush predators,” said arachnologist Jason Bond, director of the Auburn University Museum of Natural History, and author of the study describing the new species, which appeared Dec. 19 in the journal ZooKeys. “They wait at burrow entrances at night, until some dull-witted insect comes over. Then they jump out, bite it, and take it to their burrow. This particular group, they pack its carcass down into the bottom of the burrow.”

Some of the newcomers have pretty fantastic names. Aptostichus barackobamai is named for Barack Obama. Aptostichus bonoi, which lives in Joshua Tree National Park, is named after U2 band member Bono. Aptostichus sarlacc? That’s basically the Tatooine spider. It lives in the Southern California desert, and takes its name from Boba Fett’s ground-dwelling tormentor. The Atomic Penn Jillette Trapdoor spider (Aptostichus pennjillettei) is from the old nuclear testing site near Mercury, Nevada.
Male Aptostichus barackobamai. Image: Jason Bond.
Female Aptostichus barackobamai. Image: Jason Bond.
Female Aptostichus aguacaliente. Image: Jason Bond.
Female Aptostichus atomarius. Image: Jason Bond.
Female Aptostichus chavezi. Image: Jason Bond.
Male Aptostichus miwok. Image: Jason Bond.
Female Aptostichus stephencolberti. Image: Jason Bond.
Trapdoor spider burrow, closed. Image: Jason Bond.
Trapdoor spider burrow, open. Image: Jason Bond.
One of the species in this newest batch, found near a relatively young, volcanic cinder cone close to Barstow, CA, is named after Bond’s daughter, Elisabeth. Living among the lava tubes that extend from the cone, Aptostichus elisabethae builds deep, elaborate burrows that extend multiple feet into the ground. Some of the other species burrow only a few centimeters beneath the surface. “I’ve always appreciated their engineering marvels,” Bond said, noting that the spiders continually reinforce their burrow walls with silk, and that some desert species maintain a routine of “winter cleaning,” leaving little piles of excavated material outside.

Tuesday, December 18, 2012

Mayan doomsday: Civilization collapse linked to climate change

Mayan doomsday
Mayan civilization collapse and climate change
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Comalcalco was a major Mayan port city that was believed to have flourished between A.D 700 to A.D 900. Though others place it much older, and even perhaps older still, since the finds at Nakbe in the Petén, it may go back to 1000 BCE, and beyond. Since there was no rock quarry or stone to use in the area, they built the buildings out of bricks made of baked mud. The Maya raised HUGE structures made out of these bricks. That in itself makes this place unique to all the other Mayan locations. But, you see, the bricks have inscriptions on them.
The map of the Mayan Zone
Mayan ruins in Guatemala
 Where the rain forests of Guatemala now stand, a great civilization once flourished. The people of Mayan society built vast cities, ornate temples, and towering pyramids. At its peak around 900 A.D., the population numbered 500 people per square mile in rural areas, and more than 2,000 people per square mile in the cities -- comparable to modern Los Angeles County. 

This vibrant "Classic Period" of Mayan civilization thrived for six centuries. Then, for some reason, it collapsed.

The fall of the Maya has long been one of the great mysteries of the ancient world. 

The Rise and Fall of the Mayan Empire:
Sever, NASA's only archeologist, has been using satellites to examine Mayan ruins. Combining those data with conventional down-in-the-dirt archeological findings, Sever and others have managed to piece together much of what happene
From pollen trapped in ancient layers of lake sediment, scientists have learned that around 1,200 years ago, just before the civilization's collapse, tree pollen disappeared almost completely and was replaced by the pollen of weeds. In other words, the region became almost completely deforested.
 Without trees, erosion would have worsened, carrying away fertile topsoil. The changing groundcover would have boosted the temperature of the region by as much as 6 degrees, according to computer simulations by NASA climate scientist Bob Oglesby, a colleague of Sever at the MSFC. Those warmer temperatures would have dried out the land, making it even less suitable for raising crops.
Figure of a Maya priest.

Rising temperatures would have also disrupted rainfall patterns, says Oglesby. During the dry season in the Petén, water is scarce, and the groundwater is too deep (500+ feet) to tap with wells. Dying of thirst is a real threat. The Maya must have relied on rainwater saved in reservoirs to survive, so a disruption in rainfall could have had terrible consequences.
(Changes in cloud formation and rainfall are occurring over deforested parts of Central America today, studies show. Is history repeating itself?)
Using classic archeology techniques, researchers find that human bones from the last decades before the civilization's collapse show signs of severe malnutrition.
"Archeologists used to argue about whether the downfall of the Maya was due to drought or warfare or disease, or a number of other possibilities such as political instability," Sever says. "Now we think that all these things played a role, but that they were only symptoms. The root cause was a chronic food and water shortage, due to some combination of natural drought and deforestation by humans."
Throne 1 of Piedras Negras
A message from 900 A.D.: it's never too late to learn from your ancestors:
Using oxygen isotope dating on stalagmites taken from caves near various Mayan sites, scientists were able to determine precipitation levels in the area, and correlate these with known political records taken from Mayan stele and hieroglyphics.
They found, quoting materials supplied by UC Davis:
Periods of high and increasing rainfall coincided with a rise in population and political centers between A.D. 300 and 660. A climate reversal and drying trend between A.D. 660 and 1000 triggered political competition, increased warfare, overall sociopolitical instability, and finally, political collapse. This was followed by an extended drought between A.D. 1020 and 1100 that likely corresponded with crop failures, death, famine, migration and, ultimately, the collapse of the Maya population.
Temple of the Cross at Palenque; there is an intricate roof comb and corbeled arch

 Commenting on the finds from Central America, Bruce Winterhalder, from UC Davis' Native American Studies, bridges the centuries: "It's a cautionary tale about how fragile our political structure might be. Are we in danger in the same way the Classic Maya were in danger? I don't know. But I suspect that just before their rapid descent and disappearance, Maya political elites were quite confident about their achievements."

*Note: all pictures thankfully shared from various sources..

Wednesday, December 12, 2012

Scientists create new element 113: how large an atom nucleus could be

Element 113 is an atom with 113 protons in its nucleus -- a type of matter that must be created inside a laboratory because it is not found naturally on Earth. Heavier and heavier synthetic elements have been created over the years, with the most massive one being element 118, temporarily named ununoctium.
But element 113 has been stubbornly hard to create. After years of trying, researchers at the RIKEN Nishina Center for 
Accelerator-Based Science in Japan said today (Sept. 26) they finally did so. On Aug. 12, the unstable element was formed and quickly decayed, leaving the team with data to cite as proof of the accomplishment.

Elements starting with hydrogen, with the atomic number of 1, through to plutonium, 94, exist naturally. Those from 95 through the 116 have been created and confirmed, excluding those with the atomic numbers of 113 and 115.

How 113 Was Made
Kosuke Morita and his team collided zinc nuclei (30 protons) with a thin layer of bismuth (83 protons) to form nuclei with 113 protons. The nuclei underwent alpha decay, turning element 113 into element 111, 109, 107, 105, 103 and element 101, Mendelevium.
The RIKEN Linear Accelerator Facility outside of Tokyo, in which element 113 has been discovered and confirmed (Photo: RIKEN)

"For over nine years, we have been searching for data conclusively identifying element 113, and now that at last we have it, it feels like a great weight has been lifted from our shoulders," Kosuke Morita, leader of the research group, said in a statement. 

If confirmed, the achievement will mark the first time Japan has discovered a new element, and should make Japan the first Asian country with naming rights to a member of the periodic table. Until now, only scientists in the United States, Russia and Germany have had that chance.

"I would like to thank all the researchers and staff involved in this momentous result, who persevered with the belief that one day 113 would be ours," Morita said. "For our next challenge, we look to the uncharted territory of element 119 and beyond."
Dr. Kosuke Morita of the RIKEN Nishina Center for Accelerator-based Science (Photo: RIKEN)

Scientists are continually trying to create bigger and bigger atoms, both for the joy of discovery and for the knowledge these new elements can offer about how atoms work.

Most things in the universe are made of very simple elements, such as hydrogen (which has one proton), carbon (six) and oxygen (eight). For each proton, atoms generally have roughly the same number of neutrons and electrons. Yet the more protons and neutrons that are packed into an atom's nucleus, the more unstable the atom can become. Scientists wonder if there is a limit to how large atoms can be.
The decay chain for ununtrium-278, as confirmed by the known alpha decay of Db-262 into Lw-258, and that of Lw-258 into Md-254 (Image: RIKEN)

Synthesis and beginning of the decay chain for element 113 (Image: RIKEN)

The first synthetic element was created in 1940, and so far 20 different elements have been made. All of these are unstable and last only seconds, at most, before breaking apart into smaller elements.
To synthesize element 113, Morita and his team collided zinc nuclei (with 30 protons each) into a thin layer of bismuth (which contains 83 protons). When 113 was created, it quickly decayed by shedding alpha particles, which consist of two protons and two neutrons each. This process happened six times, turning element 113 into element 111, then 109, 107, 105, 103 and finally, element 101, Mendelevium (also a synthetic element).
Morita's group seemed to create element 113 in experiments conducted in 2004 and 2005, but the complete decay chain was not observed, so the discovery couldn't be confirmed. Now that this specific pattern resulting in Mendelevium has been seen, the scientists say it "provides unambiguous proof that element 113 is the origin of the chain."

Limit to how large atom can be:
Scientists have long wondered whether there is a limit to the number of protons and neutrons that can be clustered together to form the nucleus of an atom. A new study comes closer than ever to finding the answer by estimating the total number of nucleus variations that can exist.
The periodic table of elements includes 118 known species of atoms, and each of these exists (either naturally or synthetically) in several versions with differing numbers of neutrons, giving rise to a total of about 3,000 different atomic nuclei. As technology has improved over the years, physicists have been building heavier and heavier atoms — element 117 was created only last year, and researchers are hot on the trail of 119. New projects are in the works to add and subtract neutrons to known elements to create ever more exotic variations, known as isotopes. 
 In an issue of the journal Nature, researchers report that roughly 6,900 nuclides (variations of atomic nuclei), plus or minus 500, should be possible.

"Beyond the 7,000, we are talking about nuclides whose lifetimes can be so short that they can't form," said research team member Witold Nazarewicz of the University of Tennessee, the Oak Ridge National Laboratory in Tennessee and Warsaw University in Poland. "The system would decay instantly."
Even within those 7,000, the vast majority would be unstable, lasting only a tiny fraction of a second.  Of the 3,000 known nuclides, only 288 are stable.
Atoms are limited in the number of protons they can contain, because each proton is positively charged, and because "like repels like," they want to push each other away. Even neutrons, which have no charge, are slightly repulsive to each other. A mysterious force called the strong interaction, which is about 100 times stronger than electromagnetism, is what binds protons and neutrons together in nuclei.
"The nature or the exact form of the strong force, especially in heavier nuclei, is still a subject of very intense experimental and theoretical research," Nazarewicz told LiveScience.

Tuesday, December 4, 2012

Lost languages in Indian perspective

The enigma of the world's undeciphered scripts, may be it's tantalizing possibility of giving new voice to long-hushed peoples and civilizations.
'cave inscription'  found in  India>Chhattisgarh>Surguja>Ambikapur>Ramgarh
Perhaps it's the puzzle solver's delight in the mental challenges posed by breaking their codes.
Whatever the reasons, the public has long been fascinated with undeciphered ancient scripts !!

The Language of the Gods in the World of Men
Sheldon Polloc

Sheldon I. Pollock is a scholar of Sanskrit, Indian intellectual and literary history, and comparative intellectual history. He is currently the Arvind Raghunathan Professor of South Asian Studies at the Department of Middle Eastern, South Asian, and African Studies at Columbia University. He was general editor of the Clay Sanskrit Library and is founding editor of the Murty Classical Library of India. Pollock has received the Andrew W. Mellon Distinguished Achievement Award and the Government of India's Padma Sri.

'cave painting'  found in  India>Chhattisgarh>Surguja>Ambikapur>Ramgarh

  In this work of impressive scholarship, Sheldon Pollock explores the remarkable rise and fall of  Sanskrit, India's ancient language, as a vehicle of poetry and polity. The corpus of Sanskrit literature encompasses a rich tradition of poetry and drama as well as scientific, technical, philosophical and dharma texts.   He traces the two great moments of its transformation: the first around the beginning of the Common Era, when Sanskrit, long a sacred language, was reinvented as a code for literary and political expression, the start of an amazing career that saw Sanskrit literary culture spread from Afghanistan to Java. The second moment occurred around the beginning of the second millennium, when local speech forms challenged and eventually replaced Sanskrit in both the literary and political arenas. Drawing striking parallels, chronologically as well as structurally, with the rise of  Latin literature and the Roman empire, and with the new vernacular literatures and nation-states of late-medieval Europe, The Language of the Gods in the World of Men asks whether these very different histories challenge current theories of culture and power and suggest new possibilities for practice.

Crisis in the classics 

Ananya Vajpeyi teaches South Asian History at the University of Massachusetts. She was educated at the Jawaharlal Nehru University, Oxford University, where she read as a Rhodes Scholar, and the University of Chicago. 

It is stunning that in a country with dozens of Sanskrit departments at all major state-level and national universities, a number of Sanskrit colleges dating from the colonial period, an entire network of matha, pathshala, and vidyapeeth institutions comprising a parallel educational economy (especially in southern India), compulsory Sanskrit at the middle school level for millions of school children (which implies thousands of school teachers), and innumerable texts stored in homes, libraries, archives, and temples, we do not have the most basic infrastructure to read, preserve, or create knowledge in or about Sanskrit. Neither the inertia from a prior era, nor new initiatives have kept Sanskrit going.

Study needs to be undertaken for not just Sanskrit, but also a number of other classical languages, such as  Malayalam, Kannada Bengali, Tamil Persian, and Brajbhasha ( Brij)

 No Future without the past

Try to imagine independent India without its founding, fundamental, and inalienable texts, whether ancient or modern, upper  caste or  outcaste, the sermons of the Buddha, the edicts of  Aśoka, the epics of Ved Vyasa's (Mahabharata) and  Valmiki (Ramayana), the songs of its Sufis and bhakti poets ( Kabir and Tulsidas), the teachings of its saints and sages, the lessons of its gurus, the Indian Constitution of Republic of India , Mahatma Gandhi’s letters,  Dr B.R. Ambedkar’s articles, Jawaharlal Nehru’s speeches,  Rabindranath Tagore’s national anthem (Jana Gana Mana), and the innumerable stories that we continuously recount. Not land, blood, race, religion, or state – language itself is our essence. Without our words, we are nothing. 

Arguably, linguistic diversity and literary richness ought to be India’s strongest suit, given its history both as an old civilization and as a diverse and multi-vocal democracy. Alas, we have driven our languages and literatures into the ground. Linguistic chauvinism and language-centred identity politics abound. Yet, not a single political ideology protects and nurtures the languages, which remain orphans in the political process and in the networks of institutional patronage cultivated by different parties. 

It may seem perverse to worry about Sanskrit – a so-called “ dead” language – when Indians are becoming less and less fluent in the living regional languages, most of which have numerically more or as many speakers as major European and Asian languages. It may seem that with the downfall of Brahmin and upper-caste hegemony in the social, political, and cultural spheres, it was only natural for the language constitutively linked to savarna power for centuries to go into terminal decline. 

The future gloom
As usual in India, the root of the matter lies not in a shortage of money, but in the lack of a vision. Politically motivated interest, fitful as it has been, has only worsened the situation, ruining even the few centres of excellence that had survived on the intellectual steam and personal integrity of their staff until the early 1990s – University of Pune, the Deccan College Post-Graduate and Research Institute, and the Banaras Hindu University come immediately to mind.
The inscriptions found in the eastern part of India were written in the Magadhi language, using the Brahmi script. In the western part of India, the language used is closer to Sanskrit, using the Kharoshthi script, one extract of Edict 13 in the Greek language, and one bilingual edict written in Greek and Aramaic. These edicts were deciphered by British archeologist and historian James Prinsep in 1837.

James Prinsep in medal cast circa 1840. National Portrait Gallery (London)
 If the Indian education and learning continued in the present set of mood and mode then very soon the number of people capable of reading and understanding the old scriptures ( sacred languages)  shall come to naught. India is going to be the only cultural center whose literary heritage including the history shall rest in the hands of scholars from foreign countries.
  We must be connected live with our rich linguistic past. Our mythological subjects portray universal approach and paint eternal truth about humanity !!

*author Sheldon and Ananya's pictures and views shared thankfully.