Tuesday
February 1, 2005
SCIENCE
5
0 news@michigandaily.com
FOR ECASTING TI-
New 'space weather' field aims to expand the reaches of
By Steve Antalics For the Daily
Anyone who has spent time in Michigan knows
how difficult accurate weather forecasting can
be - and that's just here on Earth. Imagine
having to predict conditions across the entire chasm of
space that lies between the Earth and the sun. Yet that
daunting task is exactly what Atmospheric, Oceanic
and Space Science prof. Robert Clauer, and research-
ers like him, are hoping to do.
Clauer, co-director of the Center for Space Environ-
ment Modeling at the University's Space Physics Research
Lab, hopes to one day develop models that will be compa-
rable in accuracy to terrestrial meteorology.
While the distance between the sun and earth spans for
millions of miles, the effects of the explosive weather on
the star can extend even to our planet by disrupting satel-
lites and electrical equipment on the ground.
Clauer said, as of now, the field of space weather is still
lagging behind current weather forecasting on the earth
in terms of accuracy. "We're kind of where the meteorolo-
gists were 20 years ago," he said.
Despite the gap between technologies, Clauer added
that, "The weather models have become accurate, in part,
because they have a lot of data to put into those models.
We don't think it's going to take 20 years because we're
building on their experience and their work, although we
have some new problems to overcome."
The problem, according to Clauer, lies in the
physical size of the area that researchers are trying to
model, the sparse data on solar activity and the fact
that matter between the Earth and the Sun is distrib-
uted very unevenly, with some areas having much
denser distributions than others.
"We probably are never going to have (a high)
level of data," Clauer said. "We're trying to develop
data assimilation methods that will work with the
sparse data we have."
ButClauersaidtheirresearchutilizesthemostadvanced
computer models that are specifically geared toward pre-
dicting the weather on the sun. Adaptive mesh refinement,
a computing technique that allows multiple computers to
work simultaneously with rapidly changing areas of space
that are both empty and dense, is one such model, Clauer
explained.
To understand those different areas in space, one must
look to the activity of the sun.
"Space weather is basically looking at how the sun
and activity on the sun actually affects conditions
around the Earth," said Susan Lepri, a research fel-
low in the AOSS Department. "The sun has a con-
tinuous solar wind that's always blowing charged
particles in into space."
Solar wind is a continuous stream of charged
particles originating from the sun's atmosphere, the
corona. In addition to the solar wind, which carries
with it a magnetic field, the super-hot atmosphere of
COURTESY OF NASA/SOHO
A coronal mass ejection from the sun.
the Sun often erupts in what are known as solar
flares and coronal mass ejections.
According to Lepri the solar flares release pri- e
marily X-ray radiation, which can harm astronauts e
in space, but they also release relatively small a
amounts of charged particles. a
Coronal mass ejections, on the other hand, can release i
tens of billions of tons of charged particles into space.
The real damage to the Earth, Lepri and Clauer said,
comes from those charged particles, known as plasma,
and their interactions with everything from satellites to
power grids.
"The electrical currents have consequences -
spacecrafts can get charged and have arcing between
their components."
"Both commercial and military communications
satellites can be affected," Clauer added. The elec-
tric field induced by changing current, he said, can
wreak havoc even if it is very small, if it's conducted
across large systems such as pipelines or power grids.
This current can even blow up power transformers,
causing blackouts.
One of the largest blackouts in history, which affected
nearly six million people in Quebec in 1989, was attrib-
uted to a solar storm.
The most recent storm, caused by a coronal mass
ejection, occurred on Jan. 20, causing a brilliant aurora
in Europe but had otherwise no effect on the earth. Nev-
ertheless, power companies are particularly interested in
when the next solar storm may occur.
"If (power companies) know there is something com-
ing," Clauer explained, "they can cut back or they can re-
route power into smaller segments. But it costs money.
So you have to be able to make a prediction that's reliable.
We're not really there yet."
UPPER RIGHT
CORNER: Ultra-
hot helium erupts 'k
from the sun as
a solar flare.
iRAPHIC: "Solar wind," a stream of charged particles
jected from the sun, causes the Earth's magnetic fleid
o bend away from the Earth in a teardrop shape. The solar wind ,
nd solar flares (above) also cause "space weather" that can' &sHN5'
nterfere with satellites and electrical equipment on Earth.
solar wind
CnagletoSP
ea2t
sun
- I
LINDSEY UNGAR/Daily
Scientist finds surprising links
between arthritis and tuberculosis
By Sunil Patel
For the Daily
When Pfizer research scientist Jim Moh-
ley was asked to switch his research focus
from asthma to arthritis, he had no idea he
would stumble upon a fascinating concept
that may change the way pharmaceutical
companies develop drugs. And surprisingly
enough, he made this discovery not in the
lab but in the library.
By researching current literature, ana-
lyzing epidemiology - the study of disease
patterns in human populations - and look-
ing at archeological records, he hypoth-
esized a relationship between rheumatoid
arthritis and tuberculosis. Central to this
idea is the notion that epidemics may play a
role in human evolution.
Rheumatoid arthritis is different from
osteoarthritis - the most common form that
results from the normal wear and tear of the
joints. RA is one of the many autoimmune
diseases such as lupus, Type 1 diabetes and
multiple sclerosis.
"(Autoimmune diseases) are incorrect
usages of our immune system," Mobley said.
"Our immune system thinks that it's fighting
something foreign when it's not"
In the case of RA, the unwitting casual-
ties are usually the smaller joints, like the
fingers and wrists. According to Mobley, 1
to 2 percent of Americans are affected by
the disease.
Tuberculosis,onthe otherhand,is caused by
an infection of Mycobacterium tuberculosis.
The bacteria enter the lungs, eventually mak-
ing it very difficult for the victim tobreathe. It
is possible to carry the bacteria without con-
tracting the disease, though. While very rare
in the United States, the disease still kills two
million people each year worldwide.
On the surface, an autoimmune disorder
and a bacterial infection seem to have noth-
ing in common. The former is causedby cells
in the immune system attacking the body's
own tissue, and the latter is primarily a respi-
ratory disease causedby foreign bacteria. The
symptoms are nothing alike.
Since Mobley was unfamiliar with RA, he
was ableto examine the field with a fresh eye.
This allowed him to notice unusual trends in
the literature other scientists may have over-
looked.
"I paid attention to those things that were
unique to this disease - that really didn't
make sense to me," he said.
Two things struck a chord. First, he saw
throughout scientific studies that animals
injected with one species of bacteria were
most likely to contract RA. This species was
Mycobacterium tuberculosis.
Second, he found interesting cases
involving Enbrel, a drug used to treat RA.
Enbrel blocks tumor necrosis factor, a
chemical messenger that alerts surround-
ing cells of infection.
"It tells the surrounding cells that 'I've
been infected by something - you'd better
pay attention,' "Mobley said.
While blocking TNF stops an overactive
immune system from attacking itself, it also
sometimes caused people who carried the
tuberculosis bacteria to contract TB. This
may be because TNF is important for TB
immunity.
"There had to be, in my mind, some cau-
sality to tuberculosis," Mobley said.
Newton's apple came in the form of two
books, one on tuberculosis and one on rheu-
matoid arthritis. From one he learned where
and when the major TB epidemics had
occurred - the most recent one was over
two hundred years ago in Europe. From the
other he discovered RA was not spread out
uniformly across the world population as he
had thought - certain countries and popula-
tions had higher incidences than others. Mob-
ley had these two books within a few feet of
each other, these sources of information on
two seemingly unrelated diseases.
And in a momentof serendipity, he saw the
connection.
The higher incidences of RA "almost per-
fectly mirrored" the death rates from TB,
Mobley said. A certain Native American pop-
ulation had peak death rates from TB nearly
seven times higher than those in England and
North America over the last two hundred
years. Generations later, this same population
Conservation
expert speaks
on biodiversity
By Brandon Harig
Daily Staff Reporter
Claims of an untimely end to
human existence have persisted for
centuries, but recently, a growing
awareness of environmental issues
has awoken many to the potentially
devastating impact of mankind on
the planet.
Tomorrow Peter Raven - who
has garnered widespread attention
for his perspective on biodiversity
as a crucial peg in sustaining livable Raven
conditions on earth - will speak to
the University community about environmental challenges
for humanity.
The lecture, "Global Sustainability: Our future, our
role," is being presented through the School of Natural
Resources and Environment in cooperation with the Mat-
thaei Botonical Gardens and Nichols Arboretum. The
goal of the lecture is to bring awareness of the impor-
tance of conservation both abroad and at home.
For the talk, Raven will draw on his expertise in bio-
diversity, the preservation of biodiversity and its role in
human health and livelihood.
He will focus on the world's current environmental
condition and on future global conservation challenges.
Raven will also discuss the important role of institutions
such as the botanical gardens and Nichols Arboretum in
addressing global conservation challenges.
While high-profile lectures are common at the Uni-
versity, Raven is unusually well decorated in his field.
He has received the United States National Medal of Sci-
ence, the highest medal awarded for scientific work in
the United States.
Amid a host of smaller honors, he has also held a
MacArthur Foundation Fellowship, informally dubbed
the "genius" award. In 1999, Time featured Raven as a
"Hero for the planet."
"Dr. Raven has received just about every environ-
mental award on the planet, and is an authority on many
issues related to global sustainability, including plan-
etary extinction of biodiversity, genetically modified
organisms and the effect of climate change on biodiver-
sity," said Rosina Bierbaum, Dean of SNRE.
Though his main focus is botany, Dr. Raven is also an
expert on biodiversity and sustainability. Raven earned
his reputation when he and colleague Paul Erlich devel-
oped the notion of "co-evolution" - a theory stating
that different species evolve side-by-side, relying on
each other through each stage of evolution and grow-
ing increasingly codependent. Acclaimed for his work
as director at the Missouri Botanical Gardens, Raven is
also credited with transforming the gardens into a world-
renowned center for botanical research.
The lecture will be held in Hale Auditorium in the
Ross School's Assembly Hall tomorrow at 7:00 p.m. The
event is open to all University students and staff, as well
as to the public, and will be followed by a reception.
-Naila Moreira contributed to this report.
A microscopic image of Mycobacterlum tuberculosis, the bacteria
tuberculosis.
had rates of RA nearly seven times higher
than the rest of the world. In Africa, where
TB had been relatively nonexistent, RA was E .
now also absent. Epidemics can
Because the matching trends were more L
than 100 years apart, Mobley surmised that g e c a
the connection had something to do with essence ca usi n
genetics and natural selection.
Other diseases also possess this relation- evolution on a
ship with one another. The genetic mutation
that causes sickle cell anemia, if only present scale
on one chromosome, affords protection from
malaria. Similarly, only one mutation of the
gene that causes cystic fibrosis gives protec- Medical Hypotheses, asking
tion for cholera-induced diarrhea. Mobley arthritis a consequence o
also noted two diseases with a direct relation- tion for enhanced tubercul
ship - a mutation that provided resistance to Bruce Rothschild, who had
the bubonic plague now seems to make those archaeological evidence that
survivors' descendants HIV-resistant. hypothesis, contacted Mot
The common thread is epidemics. Epi- found thatsprior to 1785 there
demics can induce genetic change, in essence RA in Europe - only aftert
causing evolution on a small scale. Survivors TB epidemics. This suggest
of epidemics can pass their resistance on to were responsible for the exis
future generations, but those without resis- In addition, 6500-1000 ye
tance take their weak genes to the grave. place in the world Rothsch
"This is Darwinian selective pressure at its detect RA was in a small r
best," Mobley said. population between the Tens
"Genetic mutations that allowed people to Rivers. This population sho
survive tuberculosis epidemics two hundred of having had tuberculosis.
years ago are combining and coming together Because other population
in the descendants of those individuals, mak- ica showed evidence of tube
ing their immune systems very much stronger thought this Native Ame
and unfortunately, inducing these autoim- may have been a group of
mune-type diseases," he said. survived a TB epidemic, the
Mobley published his idea in the journal See ART
induce
e, in
small
g "Is rheumatoid
f natural selec-
osis resistance?"
been looking at
fit with Mobley's
bley. Rothschild
was norecord of
the occurrence of
ed the epidemics
stence of RA.
ars ago, the only
hild was able to
Native American
nessee and Green
wed no evidence
s in North Amer-
rculosis, Mobley
rican population
people who had
ir resistance then
HRITIS, Page 7
An X-ray of a patient afflicted with
arthritis