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by Terrence Aym
Ominous reports are leaking past the BP Gulf salvage operation news blackout that the disaster unfolding in the Gulf of Mexico may be about to reach biblical proportions.
251 million years ago a mammoth undersea methane bubble caused massive explosions, poisoned the atmosphere and destroyed more than 96 percent of all life on Earth. [1] Experts agree that what is known as the Permian extinction event was the greatest mass extinction event in the history of the world. [2]
55 million years later another methane bubble ruptured causing more mass extinctions during the Late Paleocene Thermal Maximum (LPTM).
The LPTM lasted 100,000 years. [3]
Those subterranean seas of methane virtually reshaped the planet when they explosively blew from deep beneath the waters of what is today called the Gulf of Mexico.
Now, worried scientists are increasingly concerned the same series of catastrophic events that led to worldwide death back then may be happening again-and no known technology can stop it.
The bottom line: BP’s Deepwater Horizon drilling operation may have triggered an irreversible, cascading geological Apocalypse that will culminate with the first mass extinction of life on Earth in many millions of years.
The oil giant drilled down miles into a geologically unstable region and may have set the stage for the eventual premature release of a methane mega-bubble.
Ryskin’s methane extinction theory
Northwestern University’s Gregory Ryskin, a bio-chemical engineer, has a theory: The oceans periodically produce massive eruptions of explosive methane gas. He has documented the scientific evidence that such an event was directly responsible for the mass extinctions that occurred 55 million years ago. [4]
Many geologists concur: “The consequences of a methane-driven oceanic eruption for marine and terrestrial life are likely to be catastrophic. Figuratively speaking, the erupting region “boils over,” ejecting a large amount of methane and other gases (e.g., CO2, H2S) into the atmosphere, and flooding large areas of land. Whereas pure methane is lighter than air, methane loaded with water droplets is much heavier, and thus spreads over the land, mixing with air in the process (and losing water as rain). The air-methane mixture is explosive at methane concentrations between 5% and 15%; as such mixtures form in different locations near the ground and are ignited by lightning, explosions and conflagrations destroy most of the terrestrial life, and also produce great amounts of smoke and of carbon dioxide…” [5]
The warning signs of an impending planetary catastrophe—of such great magnitude that the human mind has difficulty grasping it-would be the appearance of large fissures or rifts splitting open the ocean floor, a rise in the elevation of the seabed, and the massive venting of methane and other gases into the surrounding water.
Such occurrences can lead to the rupture of the methane bubble containment—it can then permit the methane to breach the subterranean depths and undergo an explosive decompression as it catapults into the Gulf waters. [6]
All three warning signs are documented to be occurring in the Gulf.
Ground zero: The Gulf Coast
The people and property located on the greater expanse of the Gulf Coast are sitting at Ground Zero. They will be the first exposed to poisonous, cancer causing chemical gases. They will be the ones that initially experience the full fury of a methane bubble exploding from the ruptured seabed.
The media has been kept away from the emergency salvage measures being taken to forestall the biggest catastrophe in human history. The federal government has warned them away from the epicenter of operations with the threat of a $40,000 fine for each infraction and the possibility of felony arrests.
Why is the press being kept away? Word is that the disaster is escalating.
Cracks and bulges
Methane is now streaming through the porous, rocky seabed at an accelerated rate and gushing from the borehole of the first relief well. The EPA is on record that Rig #1 is releasing methane, benzene, hydrogen sulfide and other toxic gases. Workers there now wear advanced protection including state-of-the-art, military-issued gas masks.
Reports, filtering through from oceanologists and salvage workers in the region, state that the upper level strata of the ocean floor is succumbing to greater and greater pressure. That pressure is causing a huge expanse of the seabed-estimated by some as spreading over thousands of square miles surrounding the BP wellhead-to bulge. Some claim the seabed in the region has risen an astounding 30 feet.
The fractured BP wellhead, site of the former Deepwater Horizon, has become the epicenter of frenetic attempts to quell the monstrous flow of methane.
The subterranean methane is pressurized at 100,000 pounds psi. According to Matt Simmons, an oil industry expert, the methane pressure at the wellhead has now skyrocketed to a terrifying 40,000 pounds psi.
Another well-respected expert, Dr. John Kessler of Texas A&M University has calculated that the ruptured well is spewing 60 percent oil and 40 percent methane. The normal methane amount that escapes from a compromised well is about 5 percent.
More evidence? A huge gash on the ocean floor—like a ragged wound hundreds of feet long—has been reported by the NOAA research ship, Thomas Jefferson. Before the curtain of the government enforced news blackout again descended abruptly, scientists aboard the ship voiced their concerns that the widening rift may go down miles into the earth.
That gash too is hemorrhaging oil and methane. It’s 10 miles away from the BP epicenter. Other, new fissures, have been spotted as far as 30 miles distant.
Measurements of the multiple oil plumes now appearing miles from the wellhead indicate that as much as a total of 124,000 barrels of oil are erupting into the Gulf waters daily-that’s about 5,208,000 gallons of oil per day.
Most disturbing of all: Methane levels in the water are now calculated as being almost one million times higher than normal. [7]
Mass death on the water
If the methane bubble—a bubble that could be as big as 20 miles wide—erupts with titanic force from the seabed into the Gulf, every ship, drilling rig and structure within the region of the bubble will immediately sink. All the workers, engineers, Coast Guard personnel and marine biologists participating in the salvage operation will die instantly.
Next, the ocean bottom will collapse, instantaneously displacing up to a trillion cubic feet of water or more and creating a towering supersonic tsunami annihilating everything along the coast and well inland. Like a thermonuclear blast, a high pressure atmospheric wave could precede the tidal wave flattening everything in its path before the water arrives.
When the roaring tsunami does arrive it will scrub away all that is left.
A chemical cocktail of poisons
Some environmentalist experts are calling what’s pouring into the land, sea and air from the seabed breach ’a chemical cocktail of poisons.’
Areas of dead zones devoid of oxygen are driving species of fish into foreign waters, killing plankton and other tiny sea life that are the foundation for the entire food chain, and polluting the air with cancer-causing chemicals and poisonous rainfalls.
A report from one observer in South Carolina documents oily residue left behind after a recent thunderstorm. And before the news blackout fully descended the EPA released data that benzene levels in New Orleans had rocketed to 3,000 parts per billion.
Benzene is extremely toxic and even short term exposure can cause agonizing death from cancerous lesions years later.
The people of Louisiana have been exposed for more than two months—and the benzene levels may be much higher now. The EPA measurement was taken in early May. [8]
Doomsday
While some say it can’t happen because the bulk of the methane is frozen into crystalline form, others point out that the underground methane sea is gradually melting from the nearby surging oil that’s estimated to be as hot as 500 degrees Fahrenheit.
Most experts in the know, however, agree that if the world-changing event does occur it will happen suddenly and within the next 6 months.
So, if events go against Mankind and the bubble bursts in the coming months, Gregory Ryskin may become one of the most famous people in the world. Of course, he won’t have long to enjoy his new found fame because very shortly after the methane eruption civilization will collapse.
Perhaps if humanity is very, very lucky, some may find a way to avoid the mass extinction that follows and carry on the human race.
Perhaps.
…………
Sources
[1] The Permian extinction event, when 96% of all marine species became extinct 251 million years ago.
[2] “The Day The Earth Nearly Died,” BBC Horizon, 2002
[3] Report about the Late Paleocene Thermal Maximum (LPTM), which occurred around 55 million years ago and lasted about 100,000 years. Large undersea methane caused explosions and mass extinctions.
[4] Ryskin Theory
Huge combustible clouds produced by methane gas trapped under the seas and explosively released could have killed off the majority of marine life, land animals, and plants at the end of the Permian era—long before the dinosaurs arrived.
[5] James P. Kennett, Kevin G. Cannariato, Ingrid L. Hendy, Richard J. Behl (2000), “Carbon Isotopic Evidence for Methane Hydrate Instability During Quaternary Interstadials,” Science 288.
[6] “An awesome mix of fire and water may lie behind mass extinctions”
[7] “Methane in Gulf ‘astonishingly high’-US scientist”
[8] Report: “Air Quality – Oil Spill” TV 4WWL video
Who Invented the Laser?
 Part of a September 1957 page from Townes’s notebook.. Physicists had been working for generations toward controlling ever shorter wavelengths. After radio (meters) and radar (centimeters, then millimeters), the logical next step would be far-infrared waves. Masers had been modestly useful, more for scientific research than for military or industrial applications. Only a few scientists thought an infrared maser might be important and pondered how to make one. Infrared rays could not be manipulated like radar, and indeed were hard to manage at all.
 Arthur Schawlow at Bell Labs, ca. 1960. After a talk with Townes, he realized that an old optical... Townes thought about the problems intensively. One day in 1957, studying the equations for amplifying radiation, he realized that it would be easier to make it happen with very short waves than with far-infrared waves. He could leap across the far-infrared region to the long-familiar techniques for manipulating ordinary light. Townes talked it over with his colleague, friend and brother-in-law Arthur Schawlow.
Listen: Arthur Schawlow recalls how Rabi inspired him to make discoveries
Schawlow found the key — put the atoms you wanted to stimulate in a long, narrow cavity with mirrors at each end. The rays would shuttle back and forth inside so that there would be more chances for stimulating atoms to radiate. One of the mirrors would be only partly silvered so that some of the rays could leak out. This arrangement (the Fabry-Pérot etalon) was familiar to generations of optics researchers.
The same arrangement meanwhile occurred to Gordon Gould, a graduate student at Columbia University who had discussed the problem with Townes. For his thesis research, Gould had already been working with “pumping” atoms to higher energy states so they would emit light. As Gould elaborated his ideas and speculated about all the things you could do with a concentrated beam of light, he realized that he was onto something far beyond the much-discussed “infrared maser”. In his notebook he confidently named the yet-to-be-invented device a LASER (for Light Amplification by Stimulated Emission of Radiation).
Listen: Gordon Gould recalls his creative moment
Listen: Peter Franken recalls hearing Gould’s exciting ideas
Gould, Schawlow and Townes now understood how to build a laser — in principle. To actually build one would require more ideas and a lot of work. Some of the ideas were already in hand. Other physicists in several countries, aiming to build better masers, had worked out various ingenious schemes to pump energy into atoms and molecules in gases and solid crystals. In a way they too were inventors of the laser. So were many others clear back to Einstein.
 Gould ca. 1985 The Patent War Gould ca. 1985
In 1957 Townes talked over some ideas about pumping light-energy into atoms with Gordon Gould, a graduate student who had been thinking along similar lines. Worried that he might be scooped, Gould wrote down his ideas for the record. He developed many more ideas of how lasers could be built and used, and in April 1959 he filed patent applications with his employer, the high-tech research firm TRG. Nine months earlier Schawlow and Townes had applied for a patent on behalf of Bell Laboratories, which employed Schawlow on staff and Townes as a consultant.
When the Bell patent was granted, Gould sued, claiming he was first to conceive the device. Legal battles raged for the next thirty years. If Gould’s patents were valid, everyone who built or used a laser would owe him money—and the longer the patents were undecided, the more valuable they became as the laser industry grew. In 1987 Gould and his backers began to win settlements. One of the greatest patent wars in history was over.
The first page of notes that Gould had notarized in November 1957. He sketched a tube with half…
 The first page of notes that Gould had notarized in November 1957. He sketched a tube with half... The historical question of how to assign credit for inventing the laser remains controversial. Most of the ideas were patented by someone, but that tells little about how the ideas actually arose and spread among scientists.
Listen: Robert Dicke recalls patenting his idea
Listen: Ali Javan comments on credit for discoveries
More reading: A historian’s thoughts on what the controversy shows about the meaning of invention
Panentheism (from Greek πᾶν (pân) “all”; ἐν (en) “in”; and θεός (Theós) “God”; “all-in-God”) A panentheistic belief system is one which posits that the one God interpenetrates every part of nature, and timelessly extends beyond as well. Panentheism is distinguished from pantheism, which holds that God is synonymous with the material universe.[1]
In panentheism, God is viewed as creator and/or animating force behind the universe, and the source of universal truth. This concept of God is closely associated with the Logos as stated in the 5th century BCE works of Heraclitus (ca. 535–475 BC), in which the Logos pervades the cosmos and whereby all thoughts and things originate; e.g., “He who hears not me but the Logos will say: All is one.” A similar thought espoused by Jesus and interpreted by Unity as being synonmous: “The Father and I are one.” (John 10:30)
Panentheism is essentially a unifying combination of theism (God is the supreme being) and pantheism (God is everything). While pantheism says that God and the universe are coextensive, panentheism claims that God is greater than the universe and that the universe is contained within God. Panentheism holds that God is the “supreme affect and effect” of the universe.
North American Indians were and still are largely panentheistic, conceiving of God (or the Sacred Other as George Tinker, a member of the Osage Nation, describes the Deep Mystery which creates and sustains all Creation in his book Spirit and Resistance: Political Theology and American Indian Liberation) as both immanent in Creation and transcendent from it. An exception is the Cherokee who were monotheistic.[citation needed] Most South American peoples were largely panentheistic as well (as were ancient South East Asian cultures).[citation needed] The Central American empires of the Mayas, Aztecs as well as the South American Incans (Tahuatinsuyu) were actually polytheistic and had very strong male deities.
Neoplatonism is polytheistic and panentheistic. Plotinus taught that there was an ineffable transcendent God (The One) of which subsequent realities were emanations. From the One emanates the Divine Mind (Nous) and the Cosmic Soul (Psyche). In Neoplatonism the world itself is a God.
In theology, monotheism (from Greek μόνος “one” and θεός “god”) is the belief in the existence of one deity, or in the oneness of God.[1] In a Western context, the concept of “monotheism” tends to be dominated by the concept of the god of the Abrahamic religions and the Platonic concept of God as put forward by Pseudo-Dionysius the Areopagite.
The concept of monotheism has largely been defined in contrast with polytheistic religions, and monotheism tends to overlap with other Unitary concepts, such as monism.
Whereas monotheism is a self-description of religions subsumed under this term, there is no equivalent self-description for polytheist religions: monotheism asserts itself by opposing polytheism, while polytheism does not use the same argumentative device, as it includes a concept of divine unity despite worshipping a plethora of gods.[2] By the same token, monotheistic religions may still include concepts of a plurality of the divine, for example the Trinity, in which God is only one but has three different persons (the Father, the Son and the Holy Spirit). Additionally, many Christians believe God to have two natures (a divine one and Human-Jesus Christ) and only God can be adored as such. Christians of a catholic tradition venerate the Saints among them Mary as human beings that had remarkable qualities, have lived their faith in God to the extreme and continue to assist in the process of salvation for others.[3]
Some argue that there are various forms of monotheism, including:
Henotheism involves devotion to a single god while accepting the existence of other gods. Similarly, monolatrism is the worship of a single deity independent of the ontological claims regarding that deity.
Theism a term that refers to the belief in the existence of a god or divine being.
Deism is a form of monotheism in which it is believed that one god exists. However, a deist rejects the idea that this god intervenes in the world.
Monistic Theism is the type of monotheism found in Hinduis, encompassing pantheism, monism, and at the same time the concept of a personal god Pantheism holds that the Universe itself is god. The existence of a transcendent supreme extraneous to nature is denied. Depending on how this is understood, such a view may well be presented as tantamount to atheism, deism or panentheism.
Panentheism, or Monistic Monotheism, is a form of theism that holds that god contains, but is not identical to, the Universe. The ‘one god’ is omnipotent and all-pervading, the universe is part of god, and god is both immanent and transcendent.
Substance monotheism, found in some indigenous African religions, holds that the many gods are different forms of a single underlying substance.
On the surface, monotheism is in contrast with polytheism, which is the worship of several deities. Polytheism is however reconcilable with Inclusive monotheism, which claims that all deities are just different names or forms for the single god. This approach is common in Hinduism, e.g. in Smartism. Exclusive monotheism, on the other hand, actively opposes polytheism. Monotheism is often contrasted with theistic dualism (ditheism). However, in dualistic theologies as that of Gnosticism, the two deities are not of equal rank, and the role of the Gnostic demiurge is closer to that of Satan in Christian theology than that of a diarch on equal terms with god (who is represented in pantheistic fashion, as Pleroma).
Ancient Middle-Eastern religions may have worshipped a single god within a pantheon and the abolition of all others, as in the case of the Aten cult in the reign of the Egyptian pharaoh Akhenaten, under the chiefly influence of the Eastern-originating Nefertiti. Iconoclasm during this pharaoh’s rule is considered a chief origin for the subsequent destruction by some groups of idols, holding that no other god before the preferred deity (dually and subtly acknowledging the existence of the other gods, but only as foes to be destroyed for their drawing of attention away from the primary deity).
Other issues such as Divine Right of Kings may possibly also stem from pharaonic laws on the ruler being the demigod or representative of the Creator on Earth. The massive tombs in the Egyptian pyramids which aligned with astronomical observations, perhaps exemplify this relationship between the pharaoh and the heavens.
Zoroastrianism is considered to be one of the earliest monotheistic beliefs, but the Zoroastrian definition of monotheism is neither comparable nor compatible with the monotheism of other religions that – in addition to being monotheistic – are also monist.
By Anne Marie Helmenstine, Ph.D., About.com Guide
See More About:chemistry faqsbiochemistryhuman scienceelements in the body
Question: What Are the Elements in the Human Body?
Answer: Most of the human body is made up of water, H2O, with cells consisting of 65-90% water by weight. Therefore, it isn’t surprising that most of a human body’s mass is oxygen. Carbon, the basic unit for organic molecules, comes in second. 99% of the mass of the human body is made up of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.
Oxygen (65%)
Carbon (18%)
Hydrogen (10%)
Nitrogen (3%)
Calcium (1.5%)
Phosphorus (1.0%)
Potassium (0.35%)
Sulfur (0.25%)
Sodium (0.15%)
Magnesium (0.05%)
Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%)
Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts)
Reference: H. A. Harper, V. W. Rodwell, P. A. Mayes, Review of Physiological Chemistry, 16th ed., Lange Medical Publications, Los Altos, California 1977.
Confirmation that biological systems use memristive systems to learn could be step towards AI
POSTED BY: Dexter Johnson // Tue, April 06, 2010
My first introduction to the discovery of the fabled memristor was right here on the pages of Spectrum and I have been hooked on this story ever since.
Whenever a new bit of information comes out about the memristor, I can’t resist the urge to read that story, or watch that video:
http://spectrum.ieee.org/nanoclast/semiconductors/nanotechnology/from-discovering-the-fourth-fundamental-circuit-element-and-then-to-artificial-intelligence-nanotechnology-leads-the-way
So when I saw Frogheart, which is a new addition to my blog roll, had written something on the latest news around the fourth fundamental circuit element, I was compelled to read it. And I’m glad I did.
The article filled me in on research that took place in 2008 in Japan, which is about the same time that R. Stanley Williams and his colleagues at HP reported that they had manufactured devices that were memristors.
The Japanese researchers were working with rather humble slime mould after having been inspired by a research group at the University of California San Diego (UC San Diego). They were able to confirm that theorist Leon Chua’s intuition that biological organisms used memristive systems to learn. Frogheart was good enough to provide the link to the article from a publication called HPlus.
This year researchers at the University of Michigan led by Dr. Wei Lu have demonstrated how synapses behave like memristors, which was published in Nano Letters.
As Frogheart says, “In the short term, scientists talk about energy savings (no need to reboot your computer when you turn it back on). In the longer term, they talk about hardware being able to learn.”
Forrest Bennett 04.06.2010
I agree that memristors are interesting and and have great potential. However you should stop passing around the incorrect idea that they are the “4th circuit element”. 1. R, L, and C all have their own units: ohm, henry, farad. But the memristor has the same units as the resistor. A true 4th circuit element would require new units. 2. If you look at the work on memcapacitors and meminductors, it becomes clear that memristors are the non-linear *generalization* of resistors, not a 4th class of device. 3. If you read Chua’s own paper, “Nonlinear circuit foundations for nanodevices”, Proc IEEE, Nov 2003, you will see that indeed Chua defines 4 fundamental classes of devices. However, the memristor and the resistor are in the *same* class. This “4th circuit element” business is marketing spin from HP, and detracts from the actual results in this area.
Fast forward to 2010 and a team at the University of Michigan led by Dr. Wei Lu showing how synapses behave like memristors (published in Nano Letters, DOI: 10.1021/nl904092h [article behind paywall]). (Fromthe HPlus site article)
Scientific American describes a US military-funded project that is trying to use the memristor “to make neural computing a reality.” DARPA’s Systems of Neuromorphic Adaptive Plastic Scalable Electronics Program (SyNAPSE) is funded to create “electronic neuromorphic machine technology that is scalable to biological levels.”
I’m not sure if the research in Michigan and elsewhere is being funded by DARPA (the US Dept. of Defense’s Defense Advanced Research Project Agency) although it seems likely.
In the short term, scientists talk about energy savings (no need to reboot your computer when you turn it back on). In the longer term, they talk about hardware being able to learn. (Thanks to the Foresight Institute for the latest update on the memristor story and the pointer to HPlus.) Do visit the HPlus site as there are some videos of scientists talking about memristors and additional information (there’s yet another team working on research that is tangentially related).
Commercializing academic research in US
Thanks to Dave Bruggeman at the Pasco Phronesis blog who’s posted some information about a White House Request for Information (RFI) on commercializing academic research. This is of particular interest not just because of the discussion about innovation in Canada but also because the US National Nanotechnology Initiative’s report to PCAST (President’s Council of Advisors on Science and Technology, my comments about the webcast of the proceedings here). From the Pasco Phronesis posting about the NNI report,
While the report notes that the U.S. continues to have a strong nanotechnology sector and corresponding support from the government. However, as with most other economic and research sectors, the rest of the world is catching up, or spending enough to try and catch up to the United States.
According to the report, more attention needs to be paid to commercialization efforts (a concern not unique to nanotechnology).
I don’t know how long the White House’s RFI has been under development but it was made public at the end of March 2010 just weeks after the latest series of reports to PCAST. As for the RFI itself, from the Pasco Phronesis posting about it,
The RFI questions are organized around two basic concerns:
» Seeking ideas for supporting the commercialization and diffusion of university research. This would include best practices, useful models, metrics (with evidence of their success), and suggested changes in federal policy and/or research funding. In addition, the RFI is interested in how commercialization ecosystems can be developed where none exist.
» Collecting data on private proof of concept centers (POCCs). These entities seek to help get research over the so-called “Valley of Death” between demonstrable research idea and final commercial product. The RFI is looking for similar kinds of information as for commercialization in general: best practices, metrics, underlying conditions that facilitate such centers.
I find the news of this RFI a little surprising since I had the impression that commercialization of academic research in the US is far more advanced than it is here in Canada. Mind you, that impression is based on a conversation I had with a researcher a year ago who commented that his mentor at a US university rolled out more than 1 start up company every year. As I understand it researchers in Canada may start up one or two companies in their career but never a series of them.
Carbon nanotubes, is exposure ok?
There’s some new research which suggests that carbon nanotubes can be broken down by an enzyme. From the news item on Nanowerk,
A team of Swedish and American scientists has shown for the first time that carbon nanotubes can be broken down by an enzyme – myeloperoxidase (MPO) – found in white blood cells. Their discoveries are presented in Nature Nanotechnology (“Carbon nanotubes degraded by neutrophil myeloperoxidase induce less pulmonary inflammation”) and contradict what was previously believed, that carbon nanotubes are not broken down in the body or in nature. The scientists hope that this new understanding of how MPO converts carbon nanotubes into water and carbon dioxide can be of significance to medicine.
“Previous studies have shown that carbon nanotubes could be used for introducing drugs or other substances into human cells,” says Bengt Fadeel, associate professor at the Swedish medical university Karolinska Institutet. “The problem has been not knowing how to control the breakdown of the nanotubes, which can caused unwanted toxicity and tissue damage. Our study now shows how they can be broken down biologically into harmless components.”
I believe they tested single-walled carbon nanotubes (CNTs) only as the person who wrote the news release seems unaware that mutil-walled CNTs also exist. In any event, this could be very exciting if this research holds up under more testing.
POSTED BY: Dexter Johnson // Mon, March 22, 2010
In a report in Nanowerk, Researchers at the Micro and Nanosystems Department, Instituto de Microelectrónica de Barcelona IMB-CNM (CSIC), led by José Antonio Plaza have successfully implanted silicon chips into living cells and manage to keep the cells alive for seven days. The research was originally published in the Wiley journal, Small.
The aim of the work was to demonstrate how our ability to create 3D-structred silicon chips on the scale of nanoparticles could enable intracellular sensors. Of course, this is a preliminary step to such possibilities since the cells were not integrated into a larger living organism in which we might see phagocytes attack the chip-impregnated cells, for instance. Or how the chips might actually transmit to an outside receiver the data it had collected inside the cell. But as we said this is a preliminary step.
An interesting point raised in the Nanowerk article is that at the current trajectory of miniaturization of silicon chips it could become possible to integrate as many as 2,500 transistors into a cell by 2020, which is roughly the equivalent to the number of transistors contained in the microprocessors of the first generation of personal computers.
While the main application for these intracellular chips would be disease detection, according to the researchers, one wonders whether the data the chips are collecting on the viability of the cell they are within is being caused by some outside diseased cells or the very presence of the chip themselves.
Based on the preliminary nature of the research, the researchers might set their sights a little higher and estimate the number of transistors that might fit in a cell by 2050.
 Long-lost relative? A nearly complete genome sequence extracted from hair of a 4,000-year-old Greenland man By Bruce Bower
Web edition : Wednesday, February 10th, 2010
A 4,000-year-old Greenland man just entered the scientific debate over the origins of prehistoric populations in the Americas.
A nearly complete sequence of nuclear DNA extracted from strands of the long-dead man’s hair — the first such sequence obtained from an ancient person — highlights a previously unknown and relatively recent migration of northeastern Asians into the New World about 5,500 years ago, scientists say.
An analysis of differences, or mutations, at single base pairs on the ancient Greenlander’s nuclear genome indicates that his father’s ancestors came from northeastern Siberia, report geneticist Morten Rasmussen of the Natural History Museum of Denmark in Copenhagen and his colleagues in the Feb. 11 Nature. Three modern hunter-gatherer groups in that region — the Nganasans, Koryaks and Chukchis — display a closer genetic link to the Greenland individual than do Native American groups living in cold northern areas of North America, Rasmussen says.
A largely complete mitochondrial DNA sequence from the ancient man’s hair, extracted by the same researchers in 2008, places his maternal ancestry in northeastern Asia as well.
Danish-led excavations more than 20 years ago unearthed four fragmentary bones and several hair tufts belonging to this ancient man, dubbed Inuk. His remains were found at a site from the Saqqaq culture, the earliest known people to have inhabited Greenland. Saqqaq people lived in Greenland from around 4,750 to 2,500 years ago. One popular hypothesis traces Saqqaq ancestry to Native American groups that had settled Arctic parts of Alaska and Canada by 11,000 years ago.
Inuk’s strong genetic ties to Siberian populations raise a different scenario. “We’ve shown that this ancient individual was not related to Native Americans but derived from an expansion of northeastern Asians into the New World and across to Greenland,” says geneticist and study coauthor Eske Willerslev of the University of Copenhagen.
The team’s new comparative analysis of Inuk’s previously sequenced mitochondrial DNA indicates that the Saqqaqs diverged from their closest present-day relatives, Siberian Chukchis, an estimated 5,400 years ago. That calculation implies that ancestral Saqqaqs separated from their Asian relatives shortly before departing for the New World and rapidly traversing that continent to reach Greenland. No land bridge connected Asia to North America at that time, so migrants probably crossed the Bering Strait from what’s now Russia to Alaska by boat, Willerslev speculates.
His group also identified base pair patterns on Inuk’s nuclear DNA that are associated in modern populations with type A-positive blood and brown eyes, as well as thick, dark hair and large, flat front teeth typical of Asians and Native Americans. Inuk also possessed DNA signatures for an increased susceptibility to baldness, dry earwax characteristic of Asian populations, and a relatively slow metabolism and broad, short body commonly found in residents of cold climates.
DNA analyses of ancient humans and their ancestors usually face enormous technical challenges. Fossil bones get contaminated with the DNA of those who unearth these finds as well as with fungal and bacterial DNA. Measures to enrich ancient DNA include generating multiple samples of the same genetic sequences and isolating genetic fragments that show no signs of contamination.
Because DNA from hair contains little contamination from fungi or bacteria, Rasmussen’s team focused on Inuk’s locks. Frozen conditions following death also helped to preserve Inuk’s DNA and prevent significant contamination. The team generated 20 copies of his genome to confirm that significant contamination had not occurred.
About 84 percent of the DNA extracted from Inuk’s hair was his. Rasmussen’s team then sequenced 79 percent of Inuk’s nuclear DNA and identified more than 353,000 base pair mutations.
“It is amazing how well-preserved this ancient genetic sample is, presumably due to its rather young age and the permafrost in which it was found,” remarks geneticist Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
In contrast, 40,000- to 70,000-year-old Neandertal bones studied by Pääbo’s team have yielded genetic sequences that, because of substantial contamination, generally include no more than 4 percent Neandertal DNA. Pääbo and his colleagues recently extracted and sequenced 63 percent of the total Neandertal genome from a bone (SN: 3/14/09, p. 5). “I am envious,” Pääbo says, referring to the completeness and quality of Inuk’s recovered DNA.
Rasmussen and Pääbo agree that a major challenge will be to sequence ancient human genomes from places where remains have not been permanently frozen and most preserved genetic material consists of microbial, rather than human, DNA.
Another challenge is to gain a firmer grasp of genetic variation in modern Arctic populations, so that scientists can more precisely trace Inuk’s geographic roots. “It will become easier to make sense of the genetic data from Greenland as more and more present-day humans become sequenced over the next few years,” Pääbo says.
by Joe Palca
NPR Radio Network
If sex is so great, how has the bdelloid rotifer been able to do without it for 30 million years? That’s a puzzle scientists at Cornell University think they have an answer to.
 Courtesy of Micrographia The bdelloid rotifer Philodina gregaria. Bdelloid rotifers are tiny invertebrates that reproduce asexually. But what is a bdelloid rotifer anyhow?
“They look like little worms,” says evolutionary biologist Chris Wilson. “About half a millimeter long with two rotating electric toothbrush heads on top that spin and filter food out of the water into their little sort of vacuum-function mouth.”
They’re found all over the world, basically anywhere there’s a drop or two of water. And as far as scientists can determine, they’re all female.
No Dating Required
The reason it’s surprising they’ve done without sex is that most multi-cellular organisms reproduce sexually, even though from a biological perspective, there’s a cost to sex. In fact, it would be much easier if you could reproduce on your own.
“You don’t have to find a mate,” says Johns Logsdon, an evolutionary biologist from the University of Iowa. “If you find a mate you don’t have to worry about things like venereal disease, you don’t have to worry about getting attacked in the process of a sex act,” says Logsdon.
A bdelloid rotifer.
Enlarge Damian H. Zanette
Bdelloid rotifers are about half a millimeter long, and can be found just about anywhere where there’s water.
A bdelloid rotifer.
Damian H. Zanette
Bdelloid rotifers are about half a millimeter long, and can be found just about anywhere where there’s water.
Another advantage of reproducing asexually is that your offspring are genetic copies of you. “Why would you mix up your genes at every generation when, in fact, you can pass 100 percent of your genes on every single time?” asks Logsdon.
And yet, nearly all multi-celled organisms — and even some single-celled organisms — choose sex.
“What we get is females sort of voluntarily submitting their genes to this random lottery,” says Wilson. “Where only half of them end up in an offspring and half of them come from the sperm of some unrelated male, who really in many species contribute very little else.”
Forget Sex, Try ‘Hide And Seek’
Many scientists think one key advantage of sex is avoiding disease. Sexual reproduction brings in new genes. And that can make a species hardier and more resistant to deadly microbes.
So how does the bdelloid rotifer get away without sex? As Wilson describes in the current issue of Science magazine, the rotifer has a remarkable defense.
“They enter a state called anhydrobiosis,” he says. “That’s life without water, and they essentially become little inanimate dust particles.”
There’s a fungus that likes to attack the rotifer. But when it’s in this desiccated state, there’s nothing for the fungus to eat. And because it’s now nothing but dust, it can blow away with the wind, with luck landing in a new, fungus-free pond.
“By playing a game of hide and seek with the parasites, [and] constantly moving to new habitats, the rotifers can outrun their parasites without needing the variation that sex would provide,” says Wilson.
Is There A Male Rotifer Somewhere Out There?
Biologist John Logsdon isn’t totally convinced that bdelloid rotifers never have sex. “Absence of evidence is not evidence of absence,” he says.
In other words, just because nobody’s ever seen a male rotifer, that’s not proof they don’t exist. Maybe they show up so rarely researchers just haven’t been patient enough. Or maybe they don’t like being watched.
Logsdon thinks that every creature that has evolved enough to have a cell with a nucleus has evolved enough to have sex. And rotifers definitely have cells with nuclei.
So maybe someday, sometime, somewhere, a bdelloid rotifer will meet Mr. Right after all.
by Christopher Joyce
NPR Radio Network
Humans are excellent two-legged walkers. It’s one of the things that make us such successful creatures.
And there are some scientists who say we’re naturally born runners as well, that our bodies evolved to run. Now, anthropologist Dan Lieberman, one of the proponents of the “human runner” school, concludes that we do it better without shoes.
He says human ancestors needed to run well — both away from big animals and after small, tasty ones, for example. He based that view on fossil bones. But lately he’s been studying runners — living ones.
It started at a lecture he gave before the Boston Marathon. A barefoot runner — someone who runs long distances without shoes — peppered the professor with questions he couldn’t answer. So Lieberman took him to his lab at Harvard University. He had him run over a flat metal plate that measures the collisional force of a footfall. Lieberman says runners generate a lot of collisional force.
“Most runners, when they land and they heel-strike — they land on their heel — they generate this sudden impulse, this sharp spike of force. So it’s like someone hitting you on the heel with a hammer, about 1 1/2 to 3 times your body weight,” he says.
Two runners: one with shoes, one without.
Benton et. al.
Most shod runners land on their heels, which generates a sudden, sharp spike of force. Barefoot runners land farther forward, closer to the ball of their foot, which exerts much less force in comparison.
But Lieberman was surprised by the extremely low force readings made by the barefoot runner.
“He ran across the force plate, and he didn’t have [a high spike], and I thought, gee, that’s really amazing, and it kind of makes sense because that spike of force hurts, and I wonder if other barefoot runners do that.”
So Lieberman tested several groups of runners: Kenyans who’d been walking and running barefoot all their lives; Americans who grew up walking and running in shoes; and some who had switched from shoes to running barefoot.
On The Ball
Lieberman found that runners in shoes usually landed heel-first. Barefoot runners landed farther forward, either on the ball of their foot or somewhere in the middle of the foot, and then the heel came down — much less collisional force.
And people who switched from shoes to barefoot running eventually, without prompting, adopted the barefoot style. Lieberman, who runs marathons himself, says the reason is simple.
“It’s pain avoidance. It’s very easy to do. I mean, your body naturally tells you what to do,” he says.
Running shoes dampen the shock of a heel-first landing, so that’s probably why shod people run that way, Lieberman says.
But is that the most efficient way to run? Lieberman thinks not.
“Turns out that the way in which barefoot runners run seems to store up more energy,” he says.
More Spring Out Of The Step
To understand how that works, I talked to anthropologist Brian Richmond at George Washington University. He points out that the human foot has an arch with ligaments inside that stretch and contract with every footfall.
“It allows the arch of the foot and the calf muscles to act as a better spring and to store up energy, and then give it back in the beginning of the next step,” Richmond says.
Think of a compressed mattress spring pushed down and then released. Richmond agrees with Lieberman that the front-first landing of barefoot running probably capitalizes on that spring mechanism more than heel-first landing — it gets more spring out of the spring.
Richmond, in fact, has discovered fossilized footprints dating back 1.5 million years. Those human ancestors who left them had an arch. They were walking when they left the prints, but Richmond suspects that when they ran, they landed front-first.
“It looks like this is how our ancestors have been running for a million years or more,” he says. “It’s only been in the last 10,000 years that we’ve had any kind of shoes, really.”
Lieberman published his findings in the journal Nature. He received research funding from a company that makes “minimal” shoes, which mimic barefoot conditions, but he adds that he received no personal income from the company. He also says he’s not taking sides over which style of running is better or safer.
“I mean, I think we have to be really, really careful about what we do and don’t know. We have not done any injury studies; this is not an injury study,” he says. That’s next.
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