Science (Vol. 305, No. 5686, August 2004)

99 Pages·2004·7.138 MB·English

E
DITORIAL
The Hydrogen Solution
I
f ever a phrase tripped lightly over the tongue, “the hydrogen economy” does. It appeals to the
futurist in all of us, and it sounds so simple: We currently have a carbon economy that pro-
duces carbon dioxide (CO ), the most prominent of the greenhouse gases that are warming up
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the world. Fortunately, however, we will eventually be able to power our cars and industries
with climate-neutral hydrogen, which produces only water.
Well, can we? This issue of Scienceexposes some of the problems, and they’re serious. To
convert the U.S. economy in this way will require a lot of hydrogen: about 150 million tons of it in
each year. That hydrogen will have to be made by extracting it from water or biomass, and that takes
energy. So, at least at first, we will have to burn fossil fuels to make the hydrogen,
which means that we will have to sequester the CO that results lest it go into the
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atmosphere. That kind of dilemma is confronted in virtually all of the proposed
routes for hydrogen production: We find a way of supplying the energy to
create the stuff, but then we have to develop other new technologies to deal
with the consequences of supplying that energy. In short, as the Viewpoint
by Turner in this issue (p. 972) makes clear, getting there will be a
monumental challenge.
In a recent article (Science, 30 July, p. 616), Secretary of Energy
Spencer Abraham calls attention to the Bush administration’s commit-
ment to the hydrogen solution. The Hydrogen Fuel Initiative and
FreedomCAR Partnership, announced in the 2003 State of the Union
message, aims “to develop hydrogen fuel cell–powered vehicles.” The
United States also led the formation of the International Partnership for the
Hydrogen Economy, a project in which Iceland, blessed with geothermal
sources and an inventive spirit, appears to be ahead of everyone else (see p. 966).
These and other initiatives are politically useful because they serve to focus public atten-
tion on the long-range goal. They rely on the premise that when the research on these new tech-
nologies is finished, we will have a better fix on the global warming problem; in the meantime, we’ll
put in place strictly voluntary measures to reduce CO emissions. That’s the case being made by the
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Bush administration.
The trouble with the plan to focus on research and the future, of course, is that the exploding
trajectory of greenhouse gas emissions won’t take time off while we are all waiting for the hydro-
gen economy. The world is now adding 6.5 billion metric tons of carbon to the atmosphere in the
form of CO annually. Some nations are cutting back on their share, but the United States, which is
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responsible for about a quarter of the world’s total, is sticking firmly to business as usual. In each
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N-FRA that might actually reduce current emissions, but current U.S. policy offers few incentives for
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www.sciencemag.org SCIENCE VOL 305 13 AUGUST 2004 917
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MARINE EXPLORATION
NSF Takes the Plunge on a
Bigger, Faster Research Sub
Deciding who will go down in history as Robert Gagosian, president of the Woods
Alvin’s last crew may be the biggest issue Hole Oceanographic Institution (WHOI) in
still on the table now that the U.S. govern- Massachusetts, which operates Alvin and
ment has decided to retire its famous re- will run the new craft. “But there’s a lot of
search submarine and build a faster, roomier, excitement about the new things we’ll be
and deeper diving substitute. Last week, the able to do.”
National Science Foundation (NSF) put an The 6 August decision ended an often
end to a decade of debate about the sub’s fu- feisty debate over how to replace Alvin,
ture by announcing that it will shelve the 40- which entered service in 1967 and is one of
five research subs in the world that can dive
below 4000 meters (Science, 19 July 2002, p.
326). Its storied, nearly 4000-dive career has
witnessed many high-profile mo- Coming out. Alvin’s last dive is scheduled for
ments, including the discovery of late 2007.
sulfur-eating sea-floor ecosystems
and visits to the Titanic. Some re- robot that could dive to 7000 meters
searchers argued for replacing the (Science, 14 November 2003, p. 1135).
aging Alvin with cheaper, in- That vehicle has yet to appear, although
creasingly capable robotic vehi- NSF officials say an automated sub currently
cles. Others wanted a human- under construction at WHOI partly fills the
Going down. piloted craft able to reach the bill. And NSF and WHOI have chosen what
New submersible will 11,000-meter bottom of the the panel judged the riskiest approach to
be able to dive 6500 meters. deepest ocean trench—far deep- building a new Alvin: starting from scratch
er than Alvin’s 4500-meter rating, which en- with a new titanium hull able to reach 6500
year-old Alvin in late 2007 and replace it ables it to reach just 63% of the sea floor. meters or 99% of the sea floor. The panel
with a $21.6 million craft packed with fea- Last year, after examining the issues, a Na- had suggested using leftover Russian or
tures long coveted by deep-sea scientists. tional Research Council panel endorsed U.S. hulls rated to at least 4500 meters,
“It’s a bittersweet moment. Alvin is a building a next-generation Alvin, but put a partly because few shipyards know how to
beloved symbol of ocean exploration,” says higher priority on constructing a $5 million work with titanium. WHOI engineers, ▲
PATENTS
NIH Declines to March In on Pricing AIDS Drug
The National Institutes of Health (NIH) has answer to a request filed in January by Essen- drug. University groups and retired govern-
rejected a controversial plea to use its legal tial Inventions, a Washington, D.C.–based ad- ment officials who wrote the law, however, ar-
muscle to rein in the spiraling cost of a vocacy group (Science, 4 June, p. 1427). It gued that such a move would be a misreading
widely used AIDS drug. NIH Director Elias asked NIH to invoke the 1980 Bayh-Dole Act, of Bayh-Dole and would undermine efforts to
Zerhouni last week said his agency would which allows the government to reclaim commercialize government-funded inventions.
not “march in” and reclaim patents on a patents on taxpayer-funded inventions if com- In a 29 July memo, Zerhouni concluded
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drug it helped develop because pricing is- panies aren’t making the resulting products that Abbott has made Norvir widely available UTIO
sues are best “left to Congress.” available to the public. Specifically, the group to the public and “that the extraordinary rem- NSTIT
The decision disappointed AIDS ac- asked NIH to march in on four patents held by edy of march-in is not an appropriate means HIC I
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universities were quietly pleased. “This was bott developed in the early 1990s with support the Federal Trade Commission (which is OCEA
the only decision NIH could make [based] from a 5-year, $3.5 million NIH grant. looking into the matter). Essential Inventions, OLE
on the law,” says Andrew Neighbour, an as- Last year, Abbott increased U.S. retail meanwhile, says it will appeal to NIH’s over- DS H
sociate vice chancellor at the University of prices for some Norvir formulations by up to seer, Health and Human Services Secretary OO
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California, Los Angeles. 400%, prompting the call for NIH to intervene Tommy Thompson. Observers doubt Thomp- DITS:
The 4 August announcement was NIH’s and allow other manufacturers to make the son will intervene. –DAVIDMALAKOFF CRE
926 13 AUGUST 2004 VOL 305 SCIENCE www.sciencemag.org
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however, are confident that hurdle can be Alvincurrently lingers about 5 hours at 2500 and the public right in the sphere,” says
overcome. meters; the new craft will last up to 7 hours. A NSF’s Emma Dieter.
Overall, the new submarine will be about new buoyancy system will allow the sub to Officials predict a smooth transition be-
the same size and shape as the current Alvin, hover in midwater, allowing researchers to tween the two craft. The biggest effect could
so that it can operate from the existing study jellyfish and other creatures that spend be stiffer competition for time on board, be-
mother ship, the Atlantis. But there will be most of their lives suspended. And an ability cause the new submersible will be able to
major improvements. to carry more weight means researchers will reach areas—such as deep-sea trenches with
One change is nearly 1 cubic meter more be able to bring more instruments—and haul interesting geology—once out of reach.
elbowroom inside the sphere that holds the pi- more samples from the depths. In the meantime, Alvin’s owner, the U.S.
lot and two passengers. It will also offer five At the same time, improved electronics Navy (NSF will own the new craft), must de-
portholes instead of the current three, and the will allow colleagues left behind to partici- cide its fate. NSF and WHOI officials will
scientists’views will overlap with the pilot’s, pate in real time. As the new vehicle sinks, also choose a name for the new vessel, al-
eliminating a long-standing complaint. A it will spool out a 12-kilometer-long fiber- though its current moniker, taken from a
sleeker design means researchers will sink to optic cable to relay data and images. “It 1960s cartoon chipmunk, appears to have
the bottom faster and be able to stay longer. will put scientists, children in classrooms, considerable support. –DAVIDMALAKOFF
SPACE SCIENCE
NASA Climate Satellite Wins Reprieve
Facing pressure from Congress and the their constituents in danger. “Your Adminis- who urged NASA Administrator Sean
White House, NASA agreed last week to tration should be able to find a few tens of O’Keefe to rethink his decision.
rethink plans to retire a climate satellite millions of dollars over the next 4 years to On 6 August, O’Keefe said he would keep
that weather forecasters have found useful preserve a key means of improving coastal TRMM going through December. He joined
for monitoring tropical storms. The space and maritime safety,” chided Representative with Lautenbacher in asking NRC, the operat-
agency said it would extend the life of the Nick Lampson (D–TX) in a 23 July letter to ing arm of the National Academies, to hold a
$600 million Tropical Rainfall Measuring the White House. “A viable funding arrange- September workshop to determine if and how
Mission (TRMM) until the end of the year ment can certainly be developed between TRMM’s operations should be continued.
and ask the National Research Council NASA and the other agencies that use Whereas NOAA is responsible for weather
(NRC) for advice on its future. TRMM’s data if you desire it to happen.” In forecasting, NASA conducts research and
TRMM, launched on a Japanese rocket an election year, that argument won the ear would prefer to divest itself of TRMM. “We’d
in 1997, measures rainfall and latent heat- of the Bush Administration, in particular, be happy to give it to NOAA or a university,”
ing in tropical oceans and land areas that NOAA Chief Conrad C. Lautenbacher Jr., says one agency official. Keeping the satellite
traditionally have been undersampled. Al- going through December will
though designed for climate researchers, cost an additional $4 million to
TRMM has also been used by meteorolo- $5 million—“and no one has de-
gists eager to improve their predictions of cided who is going to pay,” the
severe storms. “TRMM has proven helpful official added. By extending
in complementing other satellite data,” TRMM’s life, NASA hopes “to
says David Johnson, director of the Na- aid NOAA in capturing another
tional Oceanic and Atmospheric Adminis- full season of storm data,” says
tration’s (NOAA’s) weather service, which Ghassem Asrar, deputy associate
relies on a fleet of NOAA spacecraft. administrator of NASA’s new sci-
Climate and weather scientists protested ence directorate.
last month’s announcement by NASA that it Technically, satellite operators
GSFC) intended to shut off TRMM on 1 August. could keep TRMM operating an-
HAL PIERCE (SSAI/NASA NtptohhlfAaea t noSs ntraAhbeteei d lto.lm ifbtTfieeish cfsieimoiao rlamnesg eheapdan liedccaa oytrden ulestyndar oi i4dnpl l toyeoivetd eaa nr rdsestyle eol sdowacenne dgddn er ttirno f ntot hpoeteaxuundttt ocwftiootnohrmg uea lrei d t f 1w uoh8rnia tt hhmva ee oatr r ntaho3tjhi edmyscd,et oeoabnnrrusy itt c o btotorehs ftitb.osh u rNewer nA cop rSuuualpAftd-t.
D BY spring, a maneuver that would avoid a po- That option would cost about
UCE tential crash in populated areas. $36 million. Now that TRMM
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DIT:I shutting down such a spacecraft at the start Eye opener.TRMM monitored the season’s first hurricane, one of them will also have deep
CRE of the Atlantic hurricane season would put Alex,as it approached the North Carolina coast last week. pockets. –ANDREWLAWLER
www.sciencemag.org SCIENCE VOL 305 13 AUGUST 2004 927
CANCER RESEARCH ScienceScope
Proposed Leukemia Stem Cell
Encounters a Blast of Scrutiny Federal Ethics Office Faults
NIH Consulting Practices
A government review of the ongoing ethics
A prominent California stem cell lab says it rather than simply giving rise to more mature
controversy at the National Institutes of
has hit on a cadre of cells that helps explain daughter cells. This self-renewal, a defining
Health (NIH) has found significant lapses in
how a form of leukemia transitions from rel- feature of a stem cell, seemed dependent on
ative indolence to life-threatening aggres- the β-catenin pathway, which was previously the agency’s past procedures,according to a
press report.
sion. In an even more provocative claim, implicated in a number of cancers, including
In a 20-page analysis,Office of Govern-
Irving Weissman of Stanford University and a form of acute leukemia. Weissman and his
ment Ethics (OGE) acting director Marilyn
his colleagues propose in this week’s New co-authors postulate that the pathway could
Glynn charges NIH with a “permissive cul-
England Journal of Medicine that these be a new target for CML drugs aiming to
ture on matters relating to outside compen-
cells, granulocyte-macrophage progenitors, stave off or control blast crisis. sation for more than a decade,”according to
metamorphose into stem cells as the cancer Forcing expression of β-catenin protein excerpts in the 7 August Los Angeles Times.
progresses. Some cancer experts doubt the in granulocyte-macrophage progenitors OGE reportedly found instances in which
solidity of the second claim, however. from healthy volunteers enabled the cells to NIH lagged in approving outside consulting
The concept that stem cells launch and self-renew in lab dishes, the researchers re- deals or did not approve them at all,and it
sustain a cancer has gained credence as sci- port. Whereas the first stage of CML is driv- concluded that some deals raised “the ap-
entists tied such cells to several blood can- en by a mutant gene called bcr-abl, whose pearance of the use of public office for pri-
protein Gleevec targets, Weiss- vate gain.”The report,addressed to the De-
man theorizes that a β-catenin partment of Health and Human Services
surge in granulocyte- (HHS),also questions whether NIH officials
macrophage progenitors leads to should oversee the agency’s ethics program
the wild cell proliferation that given this spotty record.(As Sciencewent to
press,OGE and HHS had not released the
occurs during the dangerous
report.)
blast phase.
However,the report does not recom-
Some critics, however, say
mend a blanket ban on industry consulting,
that proof can’t come from the
according to an official who has seen it.And
petri dish. “To ultimately define a
strict new limits proposed by NIH Director
stem cell” one needs to conduct
Elias Zerhouni—including no consulting by
tests in animals, says John Dick,
high-level employees—are consistent with
the University of Toronto biolo-
the report’s recommendations,says NIH
gist who first proved the exis- spokesperson John Burklow.“We’re confi-
Outnumbered.Immature blood cells proliferate wildly as a tence of a cancer stem cell in the dent that the strong policies we are devel-
CML blast crisis takes hold. 1990s. Studies of acute myeloge- oping,in addition to the steps we have al-
nous leukemia uncovered numer- ready taken,will address the issues identi-
cers and, more recently, to breast cancer and ous progenitor cells that seemed to self-re- fied.We look forward to working with OGE
other solid tumors (Science, 5 September new, notes Dick. But when the cells were giv- as we finalize these policies,”Burklow says.
2003, p. 1308). Weissman’s group explored en to mice, many turned out not to be stem –JOCELYNKAISER
a facet of this hypothesis, asking: Can non- cells after all.
stem cells acquire such privileged status in a Michael Clarke of the University of
Biopharming Fields Revealed?
cancer environment? The investigators fo- Michigan, Ann Arbor, who first isolated
cused on chronic myelogenous leukemia stem cells in breast cancer, is more im- The U.S.Department of Agriculture (USDA)
(CML), which the drug Gleevec has earned pressed with Weissman’s results. The cells in may have to disclose the locations of
fame for treating. question “clearly self-renew,” he says. “The biotech field trials in Hawaii after losing a
The researchers gathered bone marrow implications of this are just incredible.” The round in court.The USDA issues permits for
samples from 59 CML patients at different suggestion that nonstem cells can acquire field trials of biopharmaceuticals—drug and
stages of the disease. A hallmark of CML is stemness could apply to other cancers and industrial compounds produced in plants—
its eventual shift, in patients who don’t re- shed light on how they grow, he explains. and other genetically modified crops,but it
considers the locations confidential busi-
spond to early treatment, from a chronic All agree that the next step is injecting
ness information.The agency is also worried
phase to the blast crisis, in which patients mice with granulocyte-macrophage
about vandals.
suffer a massive proliferation of immature progenitors from CML patients to see
The decision is part of a case that Earth-
blood cells. Weissman, his colleague Catri- whether the cells create a blast crisis. Weiss-
justice filed against USDA last year on be-
ona Jamieson, and their team noticed that man’s lab is conducting those studies, and
half of environmental groups,arguing that
among blood cells, the proportion of results so far look “pretty good,” he says.
field tests haven’t been adequately assessed
granulocyte-macrophage progenitors, which “What we really need to know is what
for environmental safety.Last week,a feder-
normally differentiate into several types of cells persist in those patients” who progress
al district court judge ruled that the field lo-
white blood cells, rose from 5% in chronic- to blast crisis, concludes Brian Druker, a cations must be revealed to the plantiffs to
phase patients to 40% in blast-crisis patients. leukemia specialist at Oregon Health & Sci- assess potential harm,but gave USDA 90
When grown in the lab, these cells ap- ence University in Portland. That question days to make a stronger case against public
DC peared to self-renew—meaning that one still tops the CML agenda, although Weiss- disclosure.USDA says it is studying the deci-
DIT:C granulocyte-macrophage progenitor spawned man suspects that his team has found the sion,and Earthjustice expects the agency to
CRE other functionally identical progenitor cells culprits. –JENNIFERCOUZIN appeal. –ERIKSTOKSTAD
www.sciencemag.org SCIENCE VOL 305 13 AUGUST 2004 929
N E W S O F T H E W E E K
PALEONTOLOGY at ages ranging from 2 years to 28.
Bone Study Shows T.rex Bulked Up By plotting the age of each animal
against its mass—conservatively estimated
With Massive Growth Spurt from the circumference of its femur—they
constructed growth curves for each
species. Gorgosaurus and Albertosaurus,
Tyrannosaurus rex was a creature of super- lahassee, who led the study. The reason is both more primitive tyrannosaurids, began
latives. As big as a bull elephant, T. rex that the weight-bearing bones of large to put on weight more rapidly at about age
weighed 15 times as much as the largest dinosaurs become hollow with age and the 12. For 4 years or so, they added 310 to
carnivores living on land today. Now, pale- internal tissue tends to get remodeled, thus 480 grams per day. By about age 15, they
ontologists have for the first time charted erasing growth lines. were full-grown at about 1100 kilograms.
the colossal growth spurt that carried T. rex The more advanced Daspletosaurus fol-
beyond its tyrannosaurid relatives. “It would lowed the same trend but grew faster and
have been the ultimate teenager in terms of maxed out at roughly 1800 kilograms.
food intake,” says Thomas Holtz of the Uni- T. rex, in comparison, was almost off
versity of Maryland, College Park. the chart. As the team describes this week
Growth rates have been studied in only in Nature, it underwent a gigantic growth
spurt starting at age 14 and packed on 2
kilograms a day. By age 18.5 years, the
heaviest of the lot, FMNH’s famous T. rex
named Sue, weighed more than 5600 kilo-
grams. Jack Horner of the Museum of the
Rockies in Bozeman, Montana, and Kevin
Padian of the University of California,
But leg bones aren’t the only place Berkeley, have found the same growth pat-
to check age. While studying a tyran- tern in other specimens of T. rex. Their pa-
nosaurid called Daspletosaurus at the per is in press at the Proceedings of the
Field Museum of Natural History Royal Society of London, Series B.
(FMNH) in Chicago, Illinois, Erickson It makes sense that T. rex would grow
noticed growth rings on the end of a this way, experts say. Several lines of evi-
broken rib. Looking around, he found dence suggest that dinosaurs had a higher
similar rings on hundreds of other metabolism and faster growth rates than liv-
bone fragments in the museum draw- ing reptiles do (although not as fast as
ers, including the fibula, gastralia, and birds’). Previous work by Erickson showed
Hungry. Growth rings (inset) in a rib show that Sue the pubis. These bones don’t bear sub- that young dinosaurs stepped up the pace of
grew fast during its teenage years. stantial loads, so they hadn’t been re- growth, then tapered off into adulthood; rep-
modeled or hollowed out. tiles, in contrast, grow more slowly, but they
a half-dozen dinosaurs and no large carni- Switching to modern alligators, croco- keep at it for longer. “Tyrannosaurus rex
vores. That’s because the usual method of diles, and lizards, Erickson found that the lived fast and died young,” Erickson says.
telling ages—counting annual growth rings growth rings accurately recorded the ani- “It’s the James Dean of dinosaurs.”
in the leg bone—is a tricky task with mals’ages. He and his colleagues then sam- Being able to age the animals will help
tyrannosaurids. “I was told when I started pled more than 60 bones from 20 specimens shed light on the population structure of
in this field that it was impossible to age of four closely related tyrannosaurids. Count- tyrannosaurids. For instance, the researchers
T. rex,” recalls Gregory Erickson, a paleo- ing the growth rings with a microscope, the determined the ages of more than half a
biologist at Florida State University in Tal- team found that the tyrannosaurids had died dozen Albertosaurs that apparently died ▲
PLANETARY SCIENCE
Los Alamos’s Woes Spread to Pluto Mission
The impact of the shutdown of Los Alamos from Russia and converted by Los Alamos next decade, although the likelihood and
National Laboratory in New Mexico could scientists into pellets. But the 16 July “stand timing of that possibility are in dispute.
ripple out to the distant corners of the solar down” at the lab has shut down that effort, Los Alamos officials are upbeat. “Lab
system. The lab’s closure last month due to which already was on a tight schedule due to activity is coming back on line,” says
security concerns (Science, 23 July, p. 462) the lengthy review required for any space- spokesperson Nancy Ambrosiano. Even so,
has jeopardized a NASA mission to Pluto craft containing nuclear material. last week lab director George “Pete” Nanos
and the Kuiper belt. “I am worried,” says The 2006 launch date was chosen to suspended four more employees in connec-
S. Alan Stern, a planetary scientist with the make use of a gravity assist from Jupiter to tion with the loss of several computer disks
Southwest Research Institute in Boulder, rocket the probe to Pluto by 2015. A 1-year containing classified information, and
Colorado, who is the principal investigator. delay could cost an additional 3 to 4 years in Nanos says that it could take as long as 2 M
U
That spacecraft, slated for a 2006 launch, transit time. “It won’t affect the science we months before everyone is back at work. USE
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power is not an option. Instead, the mission Some researchers fear that Pluto’s thin atmos- remedies.” DITS:
will be powered by plutonium-238, obtained phere could freeze and collapse later in the –ANDREWLAWLER CRE
930 13 AUGUST 2004 VOL 305 SCIENCE www.sciencemag.org