Posts tagged students
Population growth unsustainable, says CU prof, and the end will not be pretty
Jul 31st
“You cannot sustain population growth. It’s not debatable,” says University of Colorado Boulder Professor Emeritus Al Bartlett. “It’s based on arithmetic. It’s not debatable unless you want to debate arithmetic.”
In an educational video entitled “Population, Consumption, and Climate: A Conversation with Al Bartlett,” the professor reprises themes from his notorious talk on population. Bartlett came to CU-Boulder in 1950 to join the Department of Physics. In the 1950s and today, he notes society and governments view steady growth as the centerpiece of the global economy.
“I got to thinking about the fact that people didn’t really understand the arithmetic of steady growth,” he said. “So I put together a talk. I first gave it in September of 1969 on the arithmetic of growth.”
Bartlett has since delivered that well-known lecture more than 1,700 times to audiences worldwide. He often cites an analogy of human population growth and multiplying bacteria. Using an animation that shows bacteria doubling over a fixed period of time, the video illustrates the arithmetic of steady growth and how quickly resources are depleted as growth continues.
“There will be limits,” cautions Bartlett.
The world population topped 7 billion in March 2012, according to the United States Census Bureau. Bartlett explains that despite the fact that population growth rates in developing countries may be 3-4 times higher than the U.S. rates, a significant problem with population resides in the United States because of high per capita demand for energy and resources.
“The average child born in the United States will have, over its lifetime, 10-20 times the impact on world resources as a child born in an underdeveloped nation,” he says. “So we’ve got to address the problem at home.”
In addition to the strain on the earth’s natural resources, excessive consumption contributes to climate change because resource extraction, manufacturing, and transportation produce a great deal of carbon dioxide. And, according to Bartlett, “if any fraction of global warming can be attributed to the actions of humans, that’s all the proof you need to say the human population today is greater than the carrying capacity of the earth.”
Population, Consumption, and Climate: A Conversation with Al Bartlett is part of a video series viewable at Learn More About Climate, produced by CU-Boulder’s Office for University Outreach and Landlocked Films.
The Learn More About Climate initiative brings climate change-related information to communities across the state.The website is an online outreach tool that localizes climate change through interviews with leading scientists and everyday Coloradans to explain how climate change is affecting our state. The site also offers resources for teachers, students, policy makers, and community members who want to learn more about this critical issue.
Sign up for the Citizen’s Police Academy at the Boulder Police Department*
Jul 28th
*No criminals allowed
If you’ve ever wondered what it’s really like to be a police officer, or been interested in knowing more about the day-to-day operations at the Boulder Police Department, now is the time to sign up for the upcoming Citizen’s Police Academy course.
Nearly 800 citizens have participated over the years (this is the Department’s 29th Citizen’s Police Academy), and the new session starts on Sept. 5, 2012. It’s free and open to anyone over the age of 18. The course is held over a period of 12 weeks. Students and instructors meet once a week, from 6:30 p.m. to 9:30 p.m. on Wednesdays.
Here are a few of this session’s highlights:
- Detectives will discuss cases which have been solved, and talk about some of the ways investigations are handled;
- SWAT Team members will explain what the team does, when it’s called out, and show you some of their specialized equipment;
- Our Crime Analysts will talk about how they collect evidence at crime scenes, how various evidence is tested and how the information is used during investigations;
- The Boulder County Sheriff’s Office will give you a tour of the Boulder County Jail;
- You’ll have the opportunity to ride-along with an officer and gain some perspective about their work in the community;
- The Bomb Squad members will discuss their training and show you the equipment they use to protect them from harm;
- Learn how Dispatch Operators field 911 calls;
- Find out how records are kept, and what kind of law enforcement information is available to the public;
- And, officers who patrol Boulder will tell you about their districts and beats, and share their insights about officer safety issues.
The Citizen’s Police Academy is offered at no cost to allow community members to learn more about police operations and philosophy. Applicants should live or work in Boulder County, and be able to pass a criminal background check. To register, contact Karen MacPherson at 303-441-4325, or macphersonk@bouldercolorado.gov. Registration is open through August 27, 2012.
A graduation ceremony will be held on Dec. 5, 2012. Graduates will be able to join the Citizen’s Police Academy Alumni Association, which schedules monthly programs and speakers who focus on law enforcement-related topics.
CU research propels “Blade Runner” to Olympics
Jul 11th
University of Colorado Boulder researchers will be watching closely when South African bilateral leg amputee and sprinter Oscar Pistorius, dubbed “The Blade Runner,” makes his way to the starting block for the 400-meter sprint in the 2012 London Olympics.
Professors Rodger Kram and Alena Grabowski of the integrative physiology department have been involved in several studies analyzing the performance of amputee athletes, including Pistorius, who use blade-like, carbon fiber leg prostheses in track events. In 2007, Pistorius was barred from international competition by officials from the International Association of Athletics Federations, or IAAF, who ruled his Cheetah Flex-Foot leg prostheses conferred him an advantage over other runners.
Barred from competition, then exonerated
The decision was based in large part on a German study commissioned by the IAAF. However, data presented in April 2008 by a team that included Kram and Grabowski to the Court of Arbitration for Sport in Lausanne, Switzerland — an international group set up to settle disputes in sports — showed Pistorius gained no physiological advantage from the Cheetah prostheses over competitors. The team’s evidence and testimony played a key role in overturning the decision, allowing Pistorius to compete in able-bodied events.
The Blade Runner good to go
“The methodology of the German study that involved measuring Oscar’s oxygen consumption while running was flawed,” said Kram, who has been measuring the oxygen consumption of runners since 1983. “When we had a chance to properly measure Oscar we found that while he is quite economical in oxygen consumption compared to your average Joe, his values are well within what would be expected for a high-caliber athlete.”
At the arbitration hearings in Switzerland, Kram also argued that if a prosthetic device provides a mechanical advantage, it would very likely provide an energetic or physiological advantage. “Since there is no energetic advantage, it infers that the prostheses do not provide a mechanical advantage either,” said Kram.
Another chance
Although Pistorius subsequently failed to make the 2008 Olympic team, he was selected by South Africa’s Olympic Committee last week to run in both the individual 400 meters and a leg of the 4×400 meter relay in the 2012 Olympic Games in London, which begin on July 27. “I was delighted that Oscar was selected,” said Kram. “I was sure he’d be named to the 4×400 meter relay, but being named to the 400-meter individual event was a surprise.”
Since 2008, the research team involving CU-Boulder has continued its studies. In a 2010 study led by Grabowski, researchers used force-measuring treadmills to analyze the biomechanics of unilateral amputees — those with one amputated leg — over a wide range of running speeds. The team found the force produced by the prosthetic, carbon fiber leg was 9 percent less than that of the unaffected leg. “Applying force to the ground is crucial in sprinting events,” said Grabowski.
“We inferred that running-specific prostheses impair force generation and likely limit top sprinting speed,” said Grabowski, who received her doctorate under Kram in 2008 and recently returned to CU-Boulder as a research faculty member after doing postdoctoral work at the Massachusetts Institute of Technology. Other authors on the 2010 paper included Kram, Craig McGowan of the University of Idaho, William McDermott of the Orthopedic Specialty Hospital in Murray, Utah, and Hugh Herr of MIT.
In a 2012 paper by the same group and led by McGowan, the leg stiffness of Paralympic sprinters with both unilateral and bilateral leg amputations was compared to non-amputee sprinters across a range of speeds. The team found leg stiffness remained constant or increased with speed in non-amputees but decreased in sprinting amputees.
“During running, the leg behaves much like a spring, and the stiffness of the leg greatly influences the overall mechanics of the runner,” said Grabowski. “The study indicates that the prosthetic device limits the ability of a sprinter to change their leg stiffness during running.” In the future, she said, researchers may be able to design a prosthetic device with “adaptive stiffness” that would more accurately emulate the mechanics of a biological ankle during sprinting.
Research fueled by veterans needs
Grabowski, whose work is funded by the Veterans Administration, is particularly interested in designing better prosthetic ankle devices for military veterans or those on active duty who have undergone amputations. In collaboration with the Denver Department of Veterans Affairs, Grabowski is beginning a research effort to further develop battery-powered ankle-foot prostheses for walking and running. Such prostheses have the potential to restore mobility to users similar to the mobility they had prior to amputation, she said.
The research team is interested in locating potential test subjects in the Denver-Boulder area with leg amputations to participate in lab studies. “CU-Boulder is actively pursuing research that aims to improve the lives of amputees, particularly veterans and current military personnel,” she said. Potential study candidates can contact Grabowski at Alena.Grabowski@colorado.edu.
Research in Kram’s Locomotion Laboratory on the CU-Boulder campus goes far beyond athletics. Collaborating faculty and students are targeting the energetic costs of walking, including uphill and downhill walking in older adults; the energetics of passive cycling to treat and prevent obesity and heart disease; and studies on animal locomotion, including kangaroos, tortoises and elephants.
For more information on the CU-Boulder Locomotion Laboratory visit http://www.colorado.edu/intphys/research/locomotion.html. For more information on CU’s integrative physiology department visithttp://www.colorado.edu/intphys/.
