a peculiar tension, permitting structural changes in response
to different temperatures and pressures. In liquid form, the tetrahedral
structures allow unrestrained hydrogen bonding to occur as numerous molecules
pack into and around the tetrahedron. (Imagine a swift square dance with
dancers moving in and out of the center of the square and circling around it as
well.) The result is a dense, fluid structure, such as that of everyday tap
water.
As water approaches its freezing point
(0°C), however, the tetrahedral structure becomes more open and begins to
expand. Ordinary water reaches its maximum density at 4°C. As water continues
to cool, falling to its freezing point and below, it continues to expand.
Here, the tetrahedral arrangement is
more rigidly enforced, with molecules spaced an "arm's length" apart.
The arrangement creates a more spacious, open structure, and water becomes
lighter. If ice weren't lighter than cold water, ponds and lakes would freeze
from the bottom, rather than form a floating layer of surface ice, and water
would cease flowing in the dead of winter. Water's weirdness therefore allows
fish to swim in the water beneath the ice and plants to survive the winter
cold.
At temperatures below the freezing
point, ice crystals form around defects, such as cracks or dust particles. By
using extremely clean water samples—free from any such defects—scientists have
found ways to defy freezing and obtain supercooled liquid-water that remains
liquid below 0°C.
This procedure works only to a certain
point. At extremely cold temperatures, (–38°C and lower), it is nearly
impossible to keep water from freezing. But under certain conditions, such as
the ultrahigh pressures found deep undersea, water can remain liquid even at
such low temperatures. Scientists have been unable to make water that cold in
the laboratory, though, and so what Stanley calls a "no man's land"
of conditions had been explored only in computer simulations.
But now, using a clever technique to
confine water samples in nanoscopic pores, scientists are beginning to explore
the structure and properties of deeply supercooled water.
As even a square-dancing novice knows,
you can't hold a hoedown in a cramped, narrow hallway. Water's hydrogen-bonding
network is a fast-moving, gregarious one. Cramming water molecules into a tiny
space, with a diameter less than five water molecules wide, brings the
molecular square dance to a standstill.
"If a room were very, very
narrow, it would be hard to have a normal square dance because a lot of people
would be up against the wall and there would be no partner to grab on to,"
Stanley says. "In a similar fashion, water molecules that are confined
against a wall have only two or three arms, and the whole hydrogen-bond network
is disrupted."
Because the hydrogen-bond network
brings stability to water, the breakdown of this network changes water's
properties, allowing it to remain liquid at a much lower temperature, he says.
Scientists began exploring ways to
nanoconfine water molecules more than a decade ago, using a spongelike material
that had holes of different sizes. http://louis-j-sheehan.biz/page1.aspx
While the experiments showed that
nanoconfinement could be used to cool water well below its usual freezing
temperature, the results were often hard to interpret because water in the
larger holes would freeze, causing crystallization throughout the material.
In 2005, Sow-Hsin Chen of the
Massachusetts Institute of Technology and his colleagues found a way to get
around this problem, using a new material called MCM-41. Chung-Yuan Mou of
National Taiwan University of Taipei had created MCM-41 by refining the
fabrication of silica-nanotube assemblies. The material resembles a microscopic
beehive with a hexagonal array of holes, all uniformly sized, just a few
nanometers wide.
Curious to see how confined water
might respond in MCM-41, Chen filled the hexagonal arrays with water. He then
cooled the water to –73°C and bombarded the arrangement with neutrons. The
microscopic cells of MCM-41 not only prevented ice crystals from forming but
also allowed the scientists to probe water's molecular structure. http://louis2j2sheehan.us/page.aspx
Building on this work, Chen and
colleagues conducted a series of experiments to see how water's properties
change as temperature drops at ordinary pressures.
In 2006, Chen showed that, when cooled
below 225 kelvins (or –48°C), water's hydrogen-bonding structure undergoes a
phase transition, changing from a disordered, fluid state to a more ordered,
rigid state. Furthermore, this line of transition between a high-density liquid
and low-density liquid, called the Widom line, occurred in a continuous
fashion, as predicted by Stanley and Poole in 1992. This transition, called a
fragile-to-strong dynamic crossover, helped explain why, at superlow
temperatures, proteins and other biological molecules exist in a glassy state,
losing all flexibility and biological function.
"This dynamical transition of
protein at 225 K is triggered by its association with the hydration water,
which shows a similar dynamic transition at that temperature," Chen says.
In addition, the study showed that
water's phase change at 225 K—moving from a disordered state to a more ordered
state—violates a well-known formula called the Stokes-Einstein relation. This
formula, based on a picture of a disordered, fluid state, ties together liquid
properties such as diffusion, viscosity, and temperature, and generally works
for normal- and high-temperature liquids.
Because this formula breaks down in
subzero conditions, the experiment suggests that supercooled water may be a mix
of two liquid phases, rather than a single liquid. Chen's study, published in
the Proceedings of the National Academy of Sciences (PNAS), provided the first
experimental evidence of such "liquid polymorphism" and received the
journal's 2006 prize for best paper.
Last year, Chen and his colleagues
surprised the scientific community, and themselves, when they discovered that
under supercold conditions, liquid water again begins to expand, returning to
normal behavior. http://louis-j-sheehan-esquire.us/
Using a neutron-scattering method and
analysis to measure the density of subzero liquid water, they showed that water
reaches a minimum density at 210 K, or –63°C.
In doing the experiments, the
scientists used heavy water, or D2O, because of its neutron-scattering
properties. They then repeated the experiments using regular water and two
light-scattering techniques and came up with the same results. The findings
were reported last June in PNAS.
Though this kind of behavior had been
predicted in computer simulations, it had never been observed. The findings add
to the long list of experimental anomalies associated with supercooled water,
and provide the strongest experimental evidence yet for a second "critical
point" in liquid water, Chen says.
A critical point defines the set of
pressures and temperatures at which a liquid changes from one form to the
other. "It would be hard to explain a density minimum unless there was a
second critical point," he says.
Water already has one well-known
critical point at 647 K, or 374°C, where, under ordinary pressures, the liquid
and gas phases become identical.
MULTIPLE PERSONALITIES. Water's many
forms, or phases, change with shifts in temperature and pressure. Below –38°C,
at high enough pressures (a region researchers call "no man's land"),
water may remain liquid. The precise locations of the phase boundaries are
uncertain, but those shown here are supported by computer simulations.
"As water approaches this
critical point, the difference between water and steam grows increasingly
smaller," Stanley explains. "At the critical point, there is nothing
distinguishing water from steam, there is just one, homogeneous fluid."
More important, he says, a critical
point serves as a "tipping point," where water can exist in either of
two states, and minor fluctuations can tip the balance in one direction or the
other.
The hypersensitivity created by a
critical point can have far-reaching effects upon a system, says Stanley. In
predicting a critical point in supercooled water, he and Poole theorized that
water's crazy low-temperature behavior might account for some of its unusual
properties even at ordinary temperatures.
That's because changes at a critical
point don't occur abruptly, Stanley says. The huge changes seen near the
water-gas peak, for example, are often, if not always, foreshadowed by
fluctuations over a large range of temperatures and pressures.
"It's like looking at the highest
peak on a mountain range," Stanley says, gesturing toward a picture of
Mount Everest in his office. "The critical point, or summit, doesn't rise
out of nowhere, but rises in a gradual manner and distorts the terrain all
around it."
That means that a critical point at
–63°C might account for water's bizarre behavior at much higher temperatures,
such as its ability to expand as it cools.
Though findings from recent studies
point to the predicted second critical point, it is still too soon to know
whether such a point exists for sure. Further evidence is needed.
This year, Chen and his group will
seek some of that evidence by performing another, more far-reaching set of
experiments on supercooled water in MCM-41. Using a specially designed pressure
cell for low temperatures, the scientists will analyze changes in liquid water
as it moves from its maximum density point at 4°C to its minimum density at
–63°C and beyond under various pressures. By studying how density changes with
temperature and pressure, the researchers hope to locate the liquid-liquid
critical point precisely.
"The critical point is at a high
pressure, and no one knows exactly what it is, but we believe it's probably
above 1,000 atmospheres," Stanley says.
Other scientists are raising questions
about the extent to which supercooled water in confined volumes, no matter what
the pressure, actually behaves like cold, bulk water.
"When you put water into
confinement, it changes the way in which water molecules are arranged with
respect to each other," says C. Austen Angell, a chemist at Arizona State
University in Tempe, who studies liquid phases in supercooled water. "The
question is, how much does it change it?"
Angell notes that despite recent
progress, much remains uncertain and many of the explanations are built on
simulations that can give different results, depending on the model and tools
used in the study.
"There are other possibilities,
related to the second critical point scenario, in which the low-pressure
supercooling of uncrystallized bulk water is terminated by a first-order
[sharp] transition to a second 'low-density' liquid phase," he says.
Angell's take on supercooled water will appear in an upcoming issue of Science.
Confirming the predicted second
critical point could have an impact beyond the study of water's molecular
mysteries for their own sake.
Biologists, for example, are looking
at how this transition in liquid states, and the accompanying rigidity it
brings, affects living structures such as proteins and DNA.
Other practical benefits could flow
from the new water knowledge. For example, scientists at Cornell University
have found that high-pressure cooling of protein crystals causes them to
diffract better than they would if flash frozen, and has allowed scientists to
improve methods for crystallizing and studying proteins and other biological
tissues.
The scientists are now pursuing ways
to use high-pressure techniques to improve methods for freezing sperm and human
oocytes. The studies may lead to better ways of freezing and storing sperm for
livestock production and allow women to freeze their eggs and use them at a
later time to conceive a child.
The studies may also help explain some
more ordinary, everyday occurrences related to water's mysterious behavior.
Chen recalls hiking in New Hampshire's White Mountains, a site known for its
frigid temperatures and long months of ice, and noticing that the trees stopped
abruptly at 4,400 feet, nearly 2,000 feet below the summit of Mount Washington.
Soon after he published his findings on a minimum density, he received a phone
call from a Canadian biologist who was interested in the work.
"It turns out that this tree line
stops where the windchill temperatures reach 220 degrees K," Chen says,
noting that this is the temperature at which water's hydrogen-bonding structure
undergoes a phase transition, changing from a fluid state to a more rigid
state.
At this point water becomes very, very
slow, and no longer supports biological functions. Or, to put it another way,
the square dance of water comes to an end.
Lightning does strike twice and more
than twice in the same place, it is demonstrated by the photograph appearing on
the front cover of this week's Science News Letter. Eleven separate strokes
make up what appears to the eye as a single lightning flash.
The strokes, which come so fast that
the human eye cannot distinguish them, were photographed by General Electric
Co. scientists. The Empire State Building in New York City is the target.
The flash as the human eye sees it
(main flash in center) was caught by one camera lens, while another one,
rapidly rotating, caught the 11 separate strokes. The first one is the streak
at the right, the last one is at left. The flash took 0.36 second altogether.
The Earth's salty oceans are some 500
million to 700 million years old, almost double the accepted previous
estimates, Drs. A.C. Spencer and K.J. Murata, of the U.S. Geological Survey,
have concluded after an intensive study of oceanic chemistry.
Before the turn of the century,
geologists determined the age of the oceans by dividing the amount of salt in
them by the amount added each year. This was based on the idea that all the
salt brought to the oceans by rivers stayed there. Such an early determination
of age, after hundreds of surveys and analyses, was about 100 million years.
Later research brought the age to 350 million years, but such figures were
found to be too small. Dinosaurs are now known to have existed about 100
million years ago, and oceans obviously existed long before that.
Studying the action of clay on salt
water, Drs. Spencer and Murata in the recent work have found that some of the
salt carried to the oceans is removed by clays, and deposited on the sea floors
as a compound that does not easily dissolve. Correcting the old figures for
this salt removal gives them the new age figure of 500 million to 700 million
years.
The geologists who measure the Earth's
age by the products of the decay of radioactive elements are expected to say
the new ocean age estimates are too small. They pronounce the Earth at least 2
billion years old. While the Earth in its earlier stages may have been
oceanless, there is in the radioactive age figures plenty of room for even more
ancient oceans.
The flaming younger generation stands
condemned as the greatest group of mass murderers in America. The weapon is the
automobile.
Although including more highly skilled
automobile drivers than any other age group, 100,000 drivers between 16 and 20
years of age kill nearly twice as many on the road as the average 100,000
drivers.
Accident rates for those below 25
years of age are so high that bringing down that age group's accident rate to
the general level would save nearly 8,000 of the nearly 40,000 killed each year
on the American highway and street.
These challenging figures were
presented to the American Association for the Advancement of Science by Dr.
Harry M. Johnson, research associate for the Highway Research Board,
Washington. Young men between 19 and 21 years of age are apparently the worst
menaces on the highway, Dr. Johnson declared, pointing to a chart which
indicated plainly that young men just approaching their majority are
responsible for many more accidents per 100,000 drivers than any other group.
FOR
TODAY'S CIVILIZED WORLD, WITH ITS DOT-coms, sitcoms, ATMs, and ATVs, the first
3.5 billion years of life on Earth are a bit of an embarrassment. It was only a
few hundred million years ago that trilobites prowled the seas. More primitive
life subscribed to two or three basic lifestyles: algal mat, spineless worm, or
bacterial blob. Before that, in the Archean Eon more than 2.5 billion years
ago--well, that kind of life is what Lysol is for. http://louis-j-sheehan-esquire.us/
Scientists,
of course, see it differently. "Almost everything of any biological
importance happened back in the Archean," says Andrew Knoll of Harvard
University, author of the upcoming book Life on a Young Planet. Soon after the
infant Earth cooled down, he says, primeval microbes began processing essential
elements--carbon, sulfur, and nitrogen, among others--that allowed for the
eventual emergence of higher life-forms, including us. To this day, says Knoll,
bacteria
still do the biosphere's heavy lifting. "We just sit back and live off the
fruits of their labors."
Folks
like Knoll would like to know whom to thank for those first trophic cycles. But
in the quest to identify Earth's earliest life, geology can look a lot like
biology. It's not always easy to tell the dead organisms from the dead ends.
One of the few things experts all agree on is where to conduct the search: in
the three far-flung provinces that host the world's most ancient sedimentary rocks.
Deposits in Australia, Greenland, and South Africa offer a cryptic view of the
earth's surface as it was between 3.2 billion and 3.8 billion years ago. The
deposits are made up of layers of accumulated particles that were later buried,
heated, and compressed. Rounded pebbles and smoothed sand grains in the
sediments indicate that they were seabeds, so any life they record would be
marine.
The
oldest fossil of that life comes from a remote desert site in Western Australia
called North Pole. The rocks there bear the marks of
stromatolites--sizable mounds of mud and minerals trapped or precipitated by
microbial colonies living in shallow ocean water. Modern stromatolites grow
knee-high in Australia and the Bahamas, and the organisms that build them leave
distinctive patterns in the mud pedestal that can't be duplicated by mere
geologic manipulation. At North Pole, those patterns appear in rocks
that are almost 3.5 billion years old.
The
sediment layers in the North Pole fossils are much finer than those in modern
stromatolites, suggesting that much smaller life-forms inhabited them. Even so,
there's evidence of a food chain of sorts. The principal architects of
stromatolites are photosynthetic. They get their energy directly from sunlight
instead of feeding off other creatures. But geochemists found the chemical
signature of a microbe that was feasting on dead organic matter, a scavenger of
sorts. "We had quite sophisticated ecological communities back then, even
if they were just tiny little microbes," says astrobiologist Roger Buick
of the University of Washington, who discovered the North Pole stromatolites.
Unfortunately,
the vestiges of microbial communities are far more conspicuous than the remains
of their individual members. Lacking bones, shells, teeth, and other hard
parts, the first Earthlings didn't fossilize well. In the oldest rocks,
chemical leftovers may be the only evidence of animation. So it happens that
the earliest evidence of life is not a lithic imprint but a skewed ratio of
carbon isotopes in a chunk of rock from southwest Greenland.
Microscopic globules of graphite in the rock, documented in 1999 by
geologist Minik Rosing at the University of Copenhagen, are unusually low in a
heavy carbon isotope that gets excluded when inorganic carbon is converted into
living material. Rosing thinks the C-13-poor graphite globules might have come
from free-living planktonlike organisms that fell to the seafloor when they
died. Their remains, he says, are at least 3.7 billion years old. http://louis-j-sheehan-esquire.us/
In
1996 geochemist Stephen Mojzsis, now at the University of Colorado at Boulder,
trumped Rosing's find in a report of heavy-isotope depletion in graphite grains
from the Isua formation in Greenland and another site on the Greenland island
of Akilia. Mojzsis says the grains are 3.85 billion years old--the oldest yet.
But his interpretations of both the biological markers and the rock
itself have been put through the wringer. One of Mojzsis's former coauthors,
geochemist Gustaf Arrhenius of the Scripps Institution of Oceanography, showed
how the Isua carbon-isotopic ratio could arise by geologic activity alone, if
certain iron minerals in the rock were melted and pressed
together over time. He and other investigators also think that the putative
sedimentary rocks are actually igneous formations that have been severely
transformed by heat.
Thus,
rocks
of advanced vintage seem to confound even the most basic geologic distinction:
igneous, metamorphic, or sedimentary? "These rocks have been buried
and cooked at least three times," says Buick. "They've been severely
squashed and strained and tied in knots at least three times too. Then they sat
around for at least a billion years and got polished by glaciers. These are not
ordinary rocks."
The
ambiguity of chemical evidence leaves geologists hungry for a well-defined, and
ideally photogenic, fossil or two. In the early 1990s they thought their hopes
had been answered when paleobiologist William Schopf of the University of
California at Los Angeles described microscopic structures embedded in a
Western Australia formation almost 3.5 billion years old. In his report, dark,
slender silhouettes appear in translucent sections of thinly sliced quartz.
Schopf says the silhouettes are a complex carbon polymer made by chains of bacteria
that may have been anchored to the seafloor. After examining hundreds of
present-day microbes, he named 11 possible species in his collection and gave
the back story in a 1999 book called Cradle of Life. His menagerie made the
Guinness Book of World Records, as the Earth's oldest fossils.
"I
found a whole bunch of different things," says Schopf. "The question
was, what were they?" http://louis-j-sheehan-esquire.us/
Schopf
decided that at least half could be cyanobacteria, or blue-green algae, the
first organisms in the evolutionary record to produce oxygen. That challenges
orthodox thinking about conditions on the young Earth, which would not have had
a significant oxygen atmosphere for at least another billion years. When
geologist Martin Brasier of the University of Oxford had a look at the
structures, he decided Schopf was wrong, wrong, and wrong again. The tubes are
too branched to come from bacteria, he says. The rock
is an extrusion from a hydrothermal vent, not seafloor sediment. And the
silhouettes are inorganic carbon injected by the vent and molded into
suggestive shapes by the growth of mineral crystals. "Ancient filamentous
structures should not be accepted as being of biological origin until all
possibilities of their nonbiological origin have been exhausted," Brasier
and his coauthors wrote in a report last year.
The
hubbub over Schopf's fossils has humbled disciples of early life. "People
have become more critical about what they'll accept as evidence of
biology," says Knoll. And, as demonstrated by the recent retraction of
evidence for life in a Mars meteorite, the stakes are astronomical. Once
biologists know where and how life emerged, astrobiologists will be better
prepared to look for it elsewhere in the solar system. If life on Earth was a
freak accident born of unique and peculiar conditions, it's probably rare
elsewhere. But, says Buick, "if life can arise quickly and easily, given
the right environment, there might be quite a bit of it out there."
Some
of the earliest signs of life are found in ancient rock layers called banded
iron formations. The iron was released by underwater volcanoes and precipitated
from ocean water more than 2 billion years ago. Today the rock formations supply
about 95 percent of the iron used to make steel.
Justine Henin's 32-match winning
streak may have been ended by Maria Sharapova in the Australian Open
quarterfinals this week, but another female tennis champion hopes to continue
an even more impressive run in the tournament. Esther Vergeer of the
Netherlands, the defending women's wheelchair singles champion, is pursuing her
sixth Australian Open title and looking to solidify her claim as perhaps the
most dominant competitor in all of sports.
Entering this year's Australian Open,
Ms. Vergeer had won 303 consecutive matches. Her last loss came to Daniela Di Toro
of Australia in the quarterfinals of the Sydney Invitational in January 2003.
Before that, Ms. Vergeer had won 80 straight matches, so since May 2001, her
record is 383 wins to one loss.
Wheelchair tennis is played by the
same rules as regular tennis except that wheelchair players can hit the ball on
the second bounce. It has become a world-wide presence, with the Australian
Open, French Open, and U.S. Open including draws for wheelchair players. There
are also such premier wheelchair-only events as the Japan Open, British Open
and NEC Wheelchair Masters, plus the quadrennial Paralympic Games. Ms. Vergeer
played 99 singles and doubles matches last year (losing once in doubles), a
schedule more demanding than the ones many Association of Tennis Professionals
and World Tennis Association players pursue.
Dutch wheelchair tennis champ Esther
Vergeer's current 303-match winning streak is among the longest in all of
sports, dwarfing classic streaks like Edwin Moses' hurdles record and UCLA's
NCAA basketball streak. Only Pakistani squash champion Jahangir Khan has put
together a longer skein of wins.
PLAYER SPORT STREAK
Jahangir Khan squash 555
matches
Esther Vergeer wheelchair tennis 303
matches
Edwin Moses track and field 122 races
UCLA Bruins basketball 88 games
Martina Navratilova tennis 74 matches
Rocky Marciano heavyweight boxing 49
fights
Oklahoma Sooners college football 47 games
To put Ms. Vergeer's winning streak in
perspective, add the four longest women's winning streaks of the Open Era (74-
and 58-match streaks by Martina Navratilova; 66 by Steffi Graf; and 57 by
Margaret Court) and the total still falls short of Ms. Vergeer's streak by the
length of the longest men's Open era streak (46 matches by Guillermo Vilas in
1977).
The rest of her resume is as
impressive. She's won 21 Super Series singles titles (the wheelchair equivalent
of the Grand Slams) dating back to 2000, a total that dwarfs Roger Federer's
career total of 12. The International Tennis Federation has crowned her world
champion in her event eight consecutive years, topping Pete Sampras's six-year
mid-1990s run and Mr. Federer's still-active four-year streak.
And while Ms. Vergeer has used a
wheelchair since a childhood operation to relieve a hemorrhage left her legs
unable to move, the source of her dominance would be familiar to any tennis
fan. Her movement around the court is unparalleled, and once she gets to the
ball, she hits with pace and spin on both her one-handed backhand and her
especially effective forehand.
But one way in which Ms. Vergeer can't
compete with her counterparts on the ATP and WTA tours is in earnings. The
prize money for the entire Australian Open wheelchair event, including men's
and women's singles and doubles events, is $47,500, about the same as one
player's paycheck for losing in the third round of the men's or women's singles
draw.
While Ms. Vergeer's streak is one of
sports history's most impressive (see chart), at least one milestone looms in
the distance. Pakistani squash champion Jahangir Kahn won 555 straight matches
from 1981 to 1986. At age 26, Ms. Vergeer should keep collecting major titles
-- but there are signs that her competitors may be closing the gap. From August
2004 to October 2006, she didn't lose a set, a streak of 129 singles matches,
but last year she was forced to three sets on three occasions. So as players
like Maria Sharapova struggle for another major title in Melbourne, remember
that on an outside court, another great champion is aiming not just at victory,
but continued perfection as well.
Biologist Craig Venter and his team
replicated a bacterium's genetic structure entirely from laboratory chemicals,
moving one step closer to creating the world's first living artificial
organism.
The scientists assembled the synthetic
genome by stringing together chemicals that are the building blocks of DNA. The
synthetic genome was constructed so it included all the genes that would be
found in a naturally occurring bacterium.
The research was published in the
online version of the journal Science by a team of scientists from the J. Craig
Venter Institute in Rockville, Md. The authors include Hamilton Smith, who won
the Nobel Prize for Medicine in 1978.
"It's the second significant step
of a three-step process to create a synthetic organism," said Dr. Venter,
in a conference call with reporters. The final step could prove far trickier,
though Dr. Venter defied his critics and deciphered the human genome with
startling speed about eight years ago.
The larger quest is to make artificial
life forms with a minimum set of genes necessary for life. It is hoped that
such organisms could one day be engineered to perform commercial tasks, such as
absorbing carbon dioxide from the air or churning out biofuels.
The scientific challenge of creating
synthetic life isn't trivial, nor are the ethical and legal concerns. There is
little government oversight, and researchers involved in such experiments
regulate themselves. Detractors worry that the lack of safeguards increases the
risks that a potentially dangerous man-made organism might run amok. (In
creating the artificial genome of Mycoplasma, Dr. Venter's team disrupted the
genes that would enable it to infect other organisms.)
Nonetheless, the science is pushing
forward at a rapid pace. In June, a Venter-led team published details of an
experiment in which it inserted the DNA of one species of bacteria into the
cells of another bacteria species. That process almost magically "booted
up" the genome of the donor bacteria, sparking it to life.
The team hopes to use a similar trick
to boot up the artificially created genome, to create a man-made living
organism. But, Dr. Venter said, "there are multiple barriers" to
achieving that goal.
Dr. Venter now believes that the
challenge of creating a synthetic organism is within his grasp. "I'll
be...disappointed if we can't do it in 2008," he said.
http://louis1j1sheehan1esquire.us/page1.aspx
In Rare Middle-Class Tomb Found From Ancient Egypt
National Geographic reports on the discovery of an Egyptian tomb that was never
ransacked by robbers. Neferinpu, the priest and administrator who was buried in
the 2 X 4 meter tomb was rich, but as is often true today, his wealth was not
enough to make him upper class. His mummified body has badly decomposed because
it's from before Egyptian preservation methods had been perfected. By his side
were 4 canopic jars, 10 sealed beer jars, among other ceremonial items, and a
2-meter walking stick with a gold end.
Neferinpu was from the Old Kingdom,
5th Dynasty. Another recently discovered tomb, from the 6th dynasty contained
the remains of a dentist (see Tomb Robbers Find Egyptian Dentists' Tombs). That
tomb had been robbed in antiquity. The National Geographic article says robbers
knew it was worth robbing because while in the 5th Dynasty the king was still
in control of the burials, by the following dynasty, the central control had
weakened and individual officials had more say in their own burials and so
could make them more lavish.
The most famous Roman road is the
Appian Way (Via Appia) leading from the forum Romanum in Rome to the
southeastern coast of Italy, at Brundisium. Originally it only reached as far
as Capua, in Campania, when it was built by the censor Appius Claudius (later,
known as Ap. Claudius Caecus 'blind'), in 312 B.C., to help with the battles
Rome was fighting in the Italic peninsula.
The road was made by laying small
stones on a level dirt road and covering them with a flat layer of interlocking
stones.
The Appian Way was the site of Clodius
Pulcher's murder. Clodius Pulcher was an originally patrician (Claudian)
descendant of Appius Claudius who had joined the plebeian (Clodian) section of
the family. It was also along the Appian Way that the bodies of the rebellious
slaves from the revolt of Spartacus were crucified. Christian legend holds that
Peter had a vision of Christ along the Appian Way.
Last year, on the eve of the biggest
season of his career, Mr. Gonzalez embarked on a diet resolution that smacked
head-on with gridiron gospel as old as the leather helmet. He decided to try
going vegan.
Living solely on plant food, a
combination of nuts, fruits, vegetables, grains and the like, has long been the
fringe diet of young rebels and aging nonconformists. Even the government
recommends regular helpings of meat, fish and dairy. Vegans of late have gotten
more hip with such best sellers as the brash "Skinny Bitch," and its more
scholarly cousin, "The China Study." Both books argue vegans can live
longer.
But could an all-star National
Football League player, all 6-foot, 5-inches and 247 pounds of him, live on a
vegan diet and still excel in one of the most punishing jobs in sports?
For Mr. Gonzalez, the stakes were
high. He'd just signed a five-year contract, making him the game's highest-paid
tight-end. Entering the 2007 season, his 11th in the NFL, he had a shot at
breaking all-time NFL records for career receptions and touchdowns at his
position. To do that, he needed top performances in every game. Mr. Gonzalez
knew he was out on a limb. "I was like, 'I'm going to look like a fool if
this doesn't work out,'" he says.
Mr. Gonzalez joined a handful of elite
athletes who have put the vegan diet to the test, either for their health or
because they oppose using animals as food. But he was the first pro-football
superstar to try. And the first to fail.
Kansas City Chief Tight End Tony
Gonzalez shows us how to make high protein vegan shakes that actually taste
good. (Jan. 24)
There's no evidence a vegan diet can
improve an athlete's performance, says David Nieman, a professor of health and
exercise at Appalachian State University. His 1988 study of vegetarian runners
found they ran as well as their meat-eating rivals but no better. Although the
vegetarian athletes in his study also ate eggs and dairy foods, he says,
"there is scientific evidence that veganism, when done right, won't hurt
performance." But, he adds, there is only anecdotal evidence that it can
help.
Professional athletes, especially NFL
players, need thousands of calories a day. Many enjoy a high-protein, high-fat
smorgasbord of steaks, chops, burgers, pizza, ice cream and beer. Mr.
Gonzalez's tight-end job requires him to push around monstrously sized
opponents. Occasionally, he gets to catch a pass. Mr. Gonzalez is famous for
combining the brute power of an offensive lineman with the acrobatic skills of
a nimble receiver. "My biggest thing is strength," he says. "If
you lose that strength you get your butt kicked."
Experts say athletes in training need
as much as twice the protein of an average person to rebuild muscle. Their
bodies also require a big dose of minerals and vitamins, as well as the amino
acids, iron and creatine packed into fish, meat and dairy foods. It's fine to
be a vegan, says sports nutritionist and dietician Nancy Clark, if you're
willing to work at it. "It's harder to get calcium, harder to get protein,
harder to get Vitamin D, harder to get iron," she says. "You have to
be committed."
"Skinny Bitch" co-author Kim
Barnouin is working on another book called "Skinny Bastard." "We
want men to know that you're not going to be some scrawny little wimp if you
follow this diet," she says. The book trashes meat, milk, eggs, cheese and
sodas, saying men and women feel better and look better without them. "The
more athletes who come forward and say, 'I'm doing this for my health,' the
better," she says.
Mr. Gonzalez had never heard of the
vegan diet when he boarded a flight from New York to Los Angeles last spring,
about a month before preseason training. His seatmate turned down most of the
food offered in first class, and Mr. Gonzalez finally asked why. The man told
Mr. Gonzalez about "The China Study," a 2006 book by Cornell
professor and nutrition researcher T. Colin Campbell that claims people who eat
mostly plants have fewer deadly diseases than those who eat mostly animals. The
evidence was drawn from diet surveys and blood samples of 6,500 men and women
from across China.
Mac Danzig took a diet risk four years
ago. The 28-year-old mixed martial-arts fighter had long wanted to spare
animals by going vegan. But he was afraid his trainers were right: that he'd
lose to stronger opponents. Last month, on a diet of brown-rice protein, beans,
soy, nuts and vegetables, Mr. Danzig defeated the last of his challengers in
Spike TV's "The Ultimate Fighter." Kim Barnouin, co-author of the
vegan best-seller "Skinny Bitch," says she loves the "Ultimate
Fighter" show and cheered Mr. Danzig's win. When fight fans learned Mr.
Danzig was a vegan, some said they didn't think he'd have the strength, or the
stomach, to conquer the ultra-violent sport, which combines kick-boxing and
wrestling. "It's about animal rights," Mr. Danzig says, "not
human rights."
Mr. Gonzalez was intrigued. Earlier in
the year, a bout with Bell's Palsy, a temporary facial paralysis, had focused
his attention on health. He bought the book, and after reading the first 40
pages, he says, was convinced animal foods led to chronic illness. He was an
unlikely convert. Mr. Gonzalez, who grew up in Southern California, says
cheeseburgers were his favorite food. But he quit them, substituting fruits,
nuts and vegetables. At restaurants, he ordered pasta with tomato sauce.
Three weeks later, he walked into the
weight room at the Chiefs' training facility and got a shock. The 100-pound
dumbbells he used to easily throw around felt like lead weights. "I was
scared out of my mind," he says. Standing on the scale, he learned he'd
lost 10 pounds.
Mr. Gonzalez considered scrapping the
diet altogether and returning to the Chiefs' standard gut-busting menu. First,
though, he called Mr. Campbell, who put him in touch with Jon Hinds, himself a
vegan and the former strength coach for the Los Angeles Clippers basketball
team. Mr. Hinds suggested plant foods with more protein.
Trainers for the Atlanta Hawks worried
when shooting guard Salim Stoudamire decided to eat vegan at the end of the National
Basketball Association season in 2006. Although the diet left him craving
chicken, Mr. Stoudamire says, his biggest challenge was convincing coaches and
teammates he could still perform on the court. Team managers forced Mr.
Stoudamire onto a scale each morning of preseason training and wrote down his
weight. After holding steady at 181 pounds, the bosses got off his back. Mr.
Stoudamire says he felt better, and that his performance this season improved.
So far, none of his teammates have joined him. "They all look at me like
I'm crazy," he says.
The Chiefs' team nutritionist, Mitzi
Dulan, a former vegetarian athlete, did not believe that was enough. With the
team's prospects and Mr. Gonzalez's legacy at stake, she persuaded the
tight-end to incorporate small amounts of meat into his plant diet. Just no
beef, pork or shellfish, he said; only a few servings of fish and chicken a
week.
Teammates nicknamed him China Study
and razzed Mr. Gonzalez if he missed a block. But he wasn't ready to give up
his new diet completely. After a preseason practice, he accompanied Mr. Hinds
to learn a skill he believed as important as blocking techniques: how to shop
for groceries. Mr. Hinds showed him nutritious fish oils and how to pick out
breads dense with whole grains, nuts and seeds. "The best bread for
you," says Mr. Hinds, "is if I hit you with it, it hurts." Mr.
Gonzalez also learned how to make the fruit and vegetable shake he drinks each
morning. He stocked his pantry with tubs of soy protein powder and boxes of
organic oatmeal; soy milk and Brazilian acai juice crowded the fridge. His
favorite dessert became banana bread topped with soy whipped cream from the
vegan cafe near his home in Orange County's Huntington Beach.
Mr. Gonzalez soon recovered his lost
pounds and strength, but prospects for a record-breaking season were still in
doubt. The team lost its starting quarterback, Trent Green, in a trade, and the
Chiefs' star running back was tied up in a contract dispute.
As the season progressed, the team
lost more games than it won. But Mr. Gonzalez managed to stick to his diet and
hold onto the football. He broke the touchdown record before midseason and was
within reach of the career reception record. "I was like, 'OK, this is
working,'" he says. "I have so much more energy when I'm out
there." His wife, October Gonzalez, was astonished her husband could play
the season without ordering a single cheeseburger. "I thought he'd
cave," she says.
Mr. Gonzalez entered the final game
against the New York Jets needing four catches to surpass the record held by
former tight-end Shannon Sharpe. The contest turned into a sluggish defensive
struggle with the Chiefs trailing the Jets 7 to 3. Still, Mr. Gonzalez made
three receptions. With 2 minutes and 29 seconds left in the third quarter,
Chiefs quarterback Brodie Croyle was fleeing defenders when he threw a 9-yard
pass to Mr. Gonzalez, who scampered for a first down and a spot in the NFL
record book.
Apple finally has entered the
subnotebook market, introducing a lightweight laptop meant to please road
warriors. But, typical of Apple, the company took a different approach from its
competitors. The result is a beautiful, amazingly thin computer, but one whose
unusual trade-offs may turn off some frequent travelers.
The new aluminum-clad MacBook Air,
which I've been testing for several days, is billed as the world's thinnest
notebook computer. Its thickest point measures just three-quarters of an inch,
which is slimmer than the thinnest point on some other subnotebooks. And it
employs some innovative software features, such as fingertip gestures for its
touchpad that are similar to those on Apple's iPhone.
Walt Mossberg says Apple's first
sub-notebook computer, the MacBook Air, doesn't compromise on screen and
keyboard size, but it could mean some deal killers for frequent travelers.
Apple refused to make the most common
compromise computer makers employ to create their littlest laptops. Other
subnotebooks -- a category generally defined as weighing three pounds or less
-- have screens of just 10 to 12 inches and compressed keyboards. The
three-pound MacBook Air, by contrast, features a 13.3-inch display and a
full-size keyboard.
It's impossible to convey in words
just how pleasing and surprising this computer feels in the hand. It's so
svelte when closed that it's a real shock to discover the big screen and keyboard
inside.
But there's a price for this laptop's
daring design: Apple had to give up some features road warriors consider
standard in a subnotebook, and certain of these omissions are radical. Chief
among them is the lack of a removable battery. So, while the MacBook Air will
be a perfect choice for some travelers, I can't recommend it for all. It really
depends on your style of working on the road and what features you value most.
The MacBook Air, which will be
available next week, costs $1,800 with an 80-gigabyte hard drive and a generous
two gigabytes of memory. A second model, with a faster, cutting-edge,
64-gigabyte, solid-state drive and a slightly speedier processor, costs a
whopping $3,100. The $1,800 price for the main model isn't unusual in
subnotebooks, which can easily top $2,000, although some competitors cost less.
In my tests, the MacBook Air's screen
and keyboard were a pleasure to use. The machine felt speedy, even with
multiple programs running. And the laptop has the same Leopard operating
system, superior built-in software, and paucity of viruses and spyware that I
believe generally give the Mac an edge. I was able to install and run Windows
XP using the third-party Parallels software.
But then there are those trade-offs.
The sealed-in battery means you can't carry a spare in case you run out of
juice, and you have to bring it to a dealer when you need a new one. There's no
built-in DVD drive. The thin case can't accommodate a larger internal hard
disk. And the machine omits many common ports and connectors.
There's no Ethernet jack for wired
broadband Internet connections and no dedicated slot for the most common types
of external cellphone modems. That means that out of the box, the MacBook Air
has only one way to get on the Internet -- through its fast, built-in Wi-Fi
connection. If you're out of Wi-Fi range, you're out of luck, unless you buy an
optional, $30 add-on Ethernet connector or a cellphone modem that connects via
USB.
In fact, the MacBook Air has only
three connectors: a headphone jack, a single USB port and a port for connecting
an external monitor.
That single USB port is a problem,
because so many peripherals use USB. You can buy a tiny, cheap USB hub that
adds three more ports, but that's yet another item to carry.
The lack of a DVD drive is partly
solved by some clever software Apple included that lets you "borrow"
the DVD drive on any other Mac or Windows PC on your network, so you can
transfer files or install new software from a CD or DVD. This worked fine in my
tests, in which I installed several new programs from CDs on remote computers,
but it requires disabling third-party firewalls on Windows machines. It also doesn't
work for installing Windows on your Mac, for watching DVDs, or for playing or
importing music. For those tasks, you need an external DVD drive. Apple sells
one for $99.
In my standard battery test, where I
disable all power-saving features, set the screen brightness at maximum, turn
on the Wi-Fi and play an endless loop of music, the MacBook Air's battery
lasted 3 hours, 24 minutes. That means you could likely get 4.5 hours in a
normal work pattern, almost the five hours Apple claims.
But the MacBook Air has another
downside: its screen height. Because of the larger screen, the lid stands
higher when opened than on most other subnotebooks. So it isn't as usable as
some competitors when the seat in front of you in coach on a plane is reclined.
If you value thinness, and a large
screen and keyboard in a subnotebook, and don't watch DVDs on planes or require
spare batteries, the MacBook Air might be just the ticket. But if you rely on
spare batteries, expect the usual array of ports, or like to play DVDs on
planes, this isn't the computer to buy.
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Jose Padilla, an American once accused
of plotting with al Qaeda to detonate a radioactive "dirty bomb," was
sentenced yesterday to a relatively lenient prison term of more than 17 years
on unrelated charges.
Prosecutors, who long ago dropped the
dirty-bomb claim that made Mr. Padilla infamous, had sought life terms for Mr.
Padilla and two co-defendants, but a federal judge said authorities never
proved Mr. Padilla was a terrorist.
"There is no evidence that these
defendants personally maimed, kidnapped or killed anyone in the United States
or elsewhere," U.S. District Judge Marcia Cooke said. "There was
never a plot to overthrow the United States government."
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