Category Archives: Science

Invasive Plants: Tamarisk

To Save the West, Kill a Plant by Josh McDaniel:

The tamarisk, an invasive species introduced to the United States from Eurasia, is a deep-rooted plant that aggressively obtains water from the soil and groundwater. A single mature tree can produce up to 500,000 seeds per year, crowding out native plants along rivers and creeks and reducing wildlife habitat. The species now infests all the major rivers, springs, ditches, and wetlands in ten states—including Texas, Arizona, Utah, Colorado, New Mexico, Nevada, and California—and is rapidly expanding into others.

In the delicately dry ecosystems of the southwestern United States, that is a serious problem, adding up to over 800 billion gallons of lost water per year across the parched region. “That is equal to the water needs of 20 million people or one million acres of irrigated farmland,” said Tim Carlson, an environmental engineer and director of the Tamarisk Coalition, which aims to control the plant.

Living systems include risks for those that attempt to engineer improvement. The past is littered with examples of attempts to intervene that go wrong.

“One night, after I gave a presentation on tamarisk, an older gentleman came up to me and told me that he had earned his Eagle Scout rank by planting tamarisk to prevent soil erosion after the Dust Bowl era in the 1930s,” Carlson recalled. “He said he would gladly earn it again by helping me remove it.”

I don’t think there is a simple answer. We are going to have intentional and unintentional consequences results from our actions. To me the lesson is to learn from our past that we often have unintended consequences that are worse than we envisioned and we need to be careful. We can’t assume there are no risks that we don’t know about. There are risks we can’t predict.

Related: Invassive Plants articles – More Nutritious Wheat

Non-Newtonian Fluid Demo

via: A pool filled with non-newtonian fluid:

They filled a pool with a mix of cornstarch and water made on a concrete mixer truck. It becomes a non-newtonian fluid. When stress is applied to the liquid it exhibits properties of a solid. Video was recorded at Barcelona, Spain. A non-Newtonian fluid is a fluid in which the viscosity changes with the applied strain rate. As a result, non-Newtonian fluids may not have a well-defined viscosity.

Related: Gareth McKinley’s Non-Newtonian Fluid Dynamics Research Group – Non-Newtonian Fluid Dynamics And Applications In Geophysics – Institute of Non-Newtonian Fluid Mechanics

USA Science and Engineering Degree Data – 2007

A huge amount of interesting data can be found in NSF’s report on the USA: Women, Minorities, and Persons with Disabilities in Science and Engineering (pdf)

Since 2000 women have received more science and engineering bachelors degrees than men. Men still receive more master’s and doctoral degrees in science and engineering.

2004 bachelor’s degrees Female Male
Engineering 13,257 51,418
Computer Science 14,406 42,999
Psychology 64,208 18,302
Science and engineering 227,813 224,525
Total non-S&E 583,004 371,667

200,000 more for bachelor’s degrees for women – wow. This is just a continuation of a trend but still is fairly amazing.

2004 Master’s degrees for US citizens Female Male
Engineering 7,135 26,737
Computer Science 6,195 13,658
Psychology 11,950 3,348
Science and engineering 51,420 66,631
Total non-S&E 276,782 160,704
2004 Doctoral degrees for US citizens Female Male
Engineering 1,014 4,353
Computer Science 195 690
Psychology 2,245 1,042
Science and engineering 9,819 15,728

Some more interesting data: 90% of Asian, 60% of Native Hawaiian/other Pacific Islander 40% of Hispanic doctoral S&E faculty were born outside the United States. Over 80 % of white, American Indian/Alaska Native, and multiple race doctoral S&E faculty were born in the United States.

Related: Worldwide Science and Engineering Doctoral Degree Data – USA Under-counting Engineering Graduates – Best Research Universities Globally – Diplomacy and Science Research

Electric Cars

photo of NSF Science Cafe March 2007

The March NSF Cafe Scientifique meeting was about Electric Cars. The presenters were from the Electric Vehicle Association of DC (that site has quite a few links on this topic). In the talk the presenters mentioned Ford had produced electric cars in the 1920’s. PBS on Timeline on Electric Car History:

1893 – A handful of different makes and models of electric cars are exhibited in Chicago.
1897 – The first electric taxis hit the streets of New York City early in the year. The Pope Manufacturing Company of Connecticut becomes the first large-scale American electric automobile manufacturer.
1899 – Believing that electricity will run autos in the future, Thomas Alva Edison begins his mission to create a long-lasting, powerful battery for commercial automobiles. Though his research yields some improvements to the alkaline battery, he ultimately abandons his quest a decade later.
1900 – The electric automobile is in its heyday. Of the 4,192 cars produced in the United States 28 percent are powered by electricity, and electric autos represent about one-third of all cars found on the roads of New York City, Boston, and Chicago.

1893 was the famous Chicago World’s fair where the first Ferris Wheel was constructed and the American Society for Engineering Education was formed (I work for ASEE now). Photo by John Hunter shows a partial view of the meeting space, which is held inside the NSF headquarters.

Related: EV World РNSF Cafe Scientifique: Arlington, Virgina РCaf̩ Scientifique Directory

When Galaxies Collide

When Galaxies Collide by Kathleen M. Wong:

When two galaxies collide, what transpires is very different from, say, one billiard ball smacking into another. Instead of ricocheting away in opposite directions, galaxies are much more likely to meld together. After all, Ma points out, “Galaxies are mostly empty, so the stars and dark matter mostly just pass each other by. The chances of two stars hitting each other is tiny.” In fact, only one percent of the masses of these galaxies consists of matter we can see, such as stars and gases. The rest consists of dark matter-material we can’t see but astronomers have inferred from many observations must exist.

Actual galaxy mergers are hard to find and even harder to view. So Ma is doing the next best thing – simulating galaxy collisions using computer models. This way, she can specify the types of mergers she wants to analyze head-ons versus glancing blows; galaxies of different masses and shapes; even the occasional threesome – and analyze their fates with mathematical precision.

Engineering a Better Blood Alcohol Sensor

Scott McCain - Duke Student

Scott McCain Aims for Better Blood Alcohol Sensor:

If third-year engineering graduate student Scott McCain gets his way, the fight against drunk driving may soon be waged with a new, non-invasive blood alcohol sensor that could make standard blood or breath sample tests obsolete. The St. Louis native’s interdisciplinary research – a combination of engineering, physics and computer science – aims to build a small and inexpensive optical device capable of using harmless light to pass through skin and directly determine blood alcohol concentration.

“The device uses light at wavelengths at which skin essentially becomes transparent,” McCain said. “We shine a laser through tissue where it interacts with blood. By analyzing the scattered light that comes back out, we can determine much about the blood’s chemical content.”
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Similar devices hold promise for determining other constituents of blood. For example, they could measure cholesterol or blood sugar in a matter of minutes, McCain said. Ultimately, the goal is to have a sensor that could report a medical reading in less than 10 seconds.
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“We don’t yet know if our blood alcohol sensor will really work,” said McCain. “It wouldn’t be research if we knew what it was all about.”

Related: Inspiring a New Generation of Inventors – Re-engineered Wheelchair – Strawjet, Invention of the Year – Inventor Hired

Science and Engineering Internships

Externs.com is another curious cat web site: an internship directory. It is getting late to try and find an internship for the summer but if you are still looking you can find science internships and engineering internships via that site.

The list of companies includes: Google, Intel, NASA, Dell, NIST, Scripps Research Institute, US Navy, National Cancer Institute, Microsoft and the International Crane Foundation. If you have any internship positions you would like included you may suggest an addition.

Related: Science and Engineering Scholarships and Fellowships

NSF Cafe Scientifique: Arlington, Virgina

Cafe Scientifique NSF. Where: The Front Page, 4201 Wilson Blvd, Arlington, Virginia (Ballston Metro stop). 6:30PM-8:00PM presentation, followed by Q&A: The “Shocking” Science Behind Electric Cars:

Science makes many things possible, including alternative fuels and modes of personal transportation… Goldstein and Garlow are the President and VP of the DC area Electric Vehicle Association. They will discuss the science behind electric cars, such as fuel cells and battery technology, and some of the issues surrounding their use and acceptance. And, they will bring actual cars to touch and explore, including the MIT entry into the 1994 Tour de Sol, an electric car that is solar-powered, and an all-electric Toyota RAV4.
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Cafe Scientifique flourished first in the U.K. as a way for the public and scientists to mingle and discuss science issues in an informal setting. At least 35 cafés now exist in the U.S.

I hope to make it this month.

Related: Caf̩ Scientifique Directory РNSF Strategic Plan

Engineering Activities: for 9-12 Year Olds

Design Squad Activity page:

Unleash your kids’ ingenuity and get them thinking like engineers with these 10 DESIGN SQUAD challenges. Designed for 9-12 year olds, each challenge has step-by-step instructions and age-appropriate explanations of the main idea.

Related: Engineering Education Reality TV – Fun k-12 Science and Engineering Activities – Building minds by building robots – Middle School Engineers