Volume II Issue 3
March 2006 |
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 Sound
Waves Rock a Star to Death
 In
most explosions, there's the flash and then the "bang." But in the
exploding stars known as supernovae, it may be just the opposite. In
fact, according to new computer simulations carried out by University of
Arizona astronomer Adam Burrows and his colleagues, the bang actually
makes the flash. "It's the sound waves that actually cause the star to
explode," says Burrows.
Astronomers know that a supernova explosion can occur only in a very
massive star -- say, 10 to 25 times the mass of our own Sun. And they
know the initial release of energy is confined to the very deepest core
of the star. The puzzle is how the energy gets out. Previous simulations
suggested the layers of gas surrounding the core were just too dense for
the energy to escape.
Now, Burrows and his colleagues have developed computer models that
allow them to simulate a more natural flow of material and radiation,
especially in the central regions of the star. They found that the
initial energy release at the core pulsates the surrounding layers of
gas -- with a typical frequency around middle C. Within a fraction of a
second, moreover, the pulsations grow so violent they tear the star
apart, blowing its outer layers into space.
Student
to Counselor Ratios
 Although the
American School Counselor Association recommends a 250-to-1 ratio of
students to counselors, the national average is actually 488, according
to data from the National Center for Educational Statistics. According
to a new report for the 2003-04 school year, there were 99,395 U.S.
school counselors reported down from 100,901 (a 1.5% decrease) in
2002-2003. The national ratio increased from 1 counselor for every 478
students to 1 counselor for every 488 students. For state-by-state
student/ counselor data,
click
here.
Counselors provide a
valuable resource to students, parents, and teachers. In addition to
offering a wide variety of much needed services, counselors provide
specific career support and advice on applying for university level
education. High school students who are considering career path and
degree options are encouraged to spend as much time as possible meeting
with their school counselors to explore options based on their personal
interests and aptitudes. Students interested in careers in science,
mathematics, engineering, computing, or technology should consider
participating in special focus
national and regional programs and projects or STEM focused
summer camps.
Increase
in Advanced Placement Student Success
 The
second annual Advanced Placement Report to the Nation shows that all 50
states and the District of Columbia have achieved an increase in the
percentage of high school students earning a grade of 3 or higher in
college-level AP courses since 2000. In U.S. public schools, 14.1% of
students in the class of 2005 demonstrated mastery of an AP Exam by
earning an exam grade of 3 or higher -- the grade predictive of college
success -- on one or more AP Exams while in high school. This is up from
13.2% for the class of 2004 and 10.2% for the class of 2000.
These achievements are
noteworthy because, over the last five years, the U.S. public high
school population has increased by more than 100,000 students. U.S.
schools have done more than maintain the proportion of students who
succeed on an AP Exam before graduating from high school -- they have
increased that proportion from 10% to 14%.
Furthermore, the achievement in spreading AP courses is elevating the
quality of U.S. secondary school classrooms. Students who take AP math
and science courses in high school are much more likely than other
students to continue a course of study in science, technology,
engineering, or mathematics majors than students who do not take such
courses in high school.
The AP Program allows
students to pursue college-level studies while still in high school.
Nearly 15,000 schools worldwide participate in the AP Program, including
60% of U.S. high schools.
Find out more...
Degree
Profile: Architectural Engineering
 Architectural
engineers apply engineering principles to the construction, planning,
and design of buildings and other structures. They often work with other
engineers and with architects, who focus on function layout or
aesthetics of building projects. Architectural Engineering often
encompasses elements of other engineering disciplines, including
mechanical, electrical, fire protection, and others. Architectural
engineers are responsible for the different systems within a building,
structure, or complex. They focus on many areas including the structural
integrity of buildings to anticipate earthquakes, vibrations and wind
loads; the design and analysis of heating, ventilating, and air
conditioning systems; the efficiency and design of plumbing, fire
protection and electrical systems; acoustic and lighting plans; and
energy conservation.
 Usually,
architects design the look or aesthetics of a building and design a
building that meets the needs of a client. Architectural engineers are
responsible for taking the design and developing the details of the
building systems, including structural, heating/air conditioning,
plumbing, fire protection, and electrical. They use their expertise in
engineering, mathematics, and physics to make sure the structure is
sound and functional.
Find out more about careers in
architectural engineering.
The
Most Resilient Nanosprings in Nature
 In
a discovery that could lead to potent new "shock absorbers" and
"gate-opening springs" for molecular-scale nanomachines --as well as a
new understanding of mechanical processes within living cells --
researchers from Duke University in Durham, NC have shown that a
component of many natural proteins can act as one of the most powerful
and resilient molecular springs in nature.
Known as an "ankyrin repeat," this component occurs in hundreds of
different proteins in organisms ranging from plants to humans. In the
specialized hair cells of the inner ear, for example, ankyrin repeats
may play a critical role in converting sound, a mechanical stimulus,
into an electrical signal that can be transmitted to the brain.
Now, the Duke scientists have shown that a sufficiently long string of
ankyrin repeats will spontaneously coil into a helical structure,
forming a molecule that not only looks like a spring, but functions like
one.
"Whereas other known proteins can act like floppy springs, ankyrin
molecules behave more like steel," said Piotr Marszalek, professor of
mechanical engineering and materials science at the Duke Pratt School of
Engineering, and one of lead authors on the study. "After repeated
stretching, the molecules immediately refold themselves, retaining their
shape and strength," he explained.
"The fully extended molecules not only bounce back to their original
shape in real time, but they also generate force in the process of this
rapid refolding -- something that had never been seen before," added his
co-author Vann Bennett, a Howard Hughes Medical Institute investigator
and professor of cell biology at Duke University Medical Center and
investigator.
Marszalek and Bennett are participants in the
Duke University
Center for Biologically Inspired Materials and Material Systems, and
were supported in this work by Duke University and the National Science
Foundation.
Industry
Uses NASA Wind Tunnels to Design Airplanes
 NASA-developed
wind tunnel technology is being used by the aviation industry to perfect
new airplane designs throughout the entire development process. The
Boeing Company is one manufacturer that is purchasing wind tunnel time
in the U.S. National Transonic Facility at NASA's Langley Research
Center in Hampton, VA, to test new aviation concepts, before applying
them in flight.
Boeing is evaluating high-lift system designs for its new 787 jet
aircraft. High-lift systems include the flaps and slats used to increase
the lift performance of the wing, allowing the airplane to take off and
land safely and efficiently. "Unlike conventional wind tunnels, the
National Transonic Facility can duplicate the aerodynamics of the flight
environment, even with small scale models," said facility chief
aerodynamicist Rich Wahls. "That allows the aircraft manufacturers to
produce better performing airplanes with less risk."
To test its new high-lift concepts, Boeing developers designed new
787-style trailing edge flaps and fit them to an existing 5.2 percent
scale 777 semi-span model. The stainless steel model, which looks like
one-half of an airplane cut down the middle from nose to tail, is
mounted on the sidewall of the wind tunnel. Even small improvements in
performance of a high-lift system can significantly improve the take-off
field length, weight carrying capability, and range of a transport
aircraft. The improvements can also help reduce aircraft noise. But
making improvements is not easy, because of the complex airflow issues
encountered when flaps and slats are extended from a wing. More info
about wind tunnels is available
online. Find out more
about careers in aerospace
engineering...
Link
to the Sloan Career Cornerstone Center From Your Counseling, School, or Department
Website
 Many
college career centers, welcome centers, and admissions offices --
along with engineering, math, and science departments -- link to the
Sloan Career Cornerstone Center from their websites to help students and
others tap into the Sloan Career Cornerstone Center's free career resources. High School
counseling departments also link to the Sloan Career Cornerstone Center to provide
college-bound students with university and career information.
Click here for graphics and other
resources.
Career Cornerstone News is a publication of the
Sloan Career Cornerstone Center. Click here
to subscribe.
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