February 2011 Archives

The after-effects of Hungary's red mud disaster are still unknown. Concerns over the coming year's crops are high. (Image source: WHO/Roger Aertgeerts)

Almost six months later, scientists are still trying to assess the damage, both long-term and immediate, caused by the red mud, which contains both toxic metals and radioactive elements. From studies on the pulmonary effects of inhaling red mud dust to studies of the soil the sludge flowed over, there are many questions that remain unanswered.

Studies have suggested that the presence of large quantities of heavy metals (like nickel) left in the wake of red mud could have an impact upon the micro fauna of the soil that might take many years to resolve or reverse. Toxic metals, however, may be only part of the post-disaster problem for agriculture in Hungary.

The pH of Planting

Recent studies suggest that an immediate challenge for farmers will be dealing with soil that might be considered super alkaline. As Science Daily reported, "Red mud is about one million times more alkaline than a neutral material."

Couple the extreme alkalinity with the fact that Hungarian farmlands were covered in up to 4 inches of sludge, and it's clear that farmers whose livelihoods depend upon local crops like corn and alfalfa have a right to be concerned. Whether the crops will be safe to eat remains a big question. But farmers also have to ask, "will the crops grow?" Will they grow at all? Will growth cycles change? Will the yield differ from a pre-red mud season?

One solution scientists have explored to help lower the pH levels of the soil is the addition of gypsum. We'll be watching as the agricultural story unfolds. But students can observe these issues firsthand with a series of plant biology projects that puts real-world environmental disaster relief onto their windowsills or into their backyard garden:

• To monitor the effects of pH on germination, students can modify the core experimental procedure used in the Radiant Radish Seeds project. Using varying amounts of baking soda mixed with water, students can test pH levels and study the effects of alkalinity on germination.
• To explore plant growth in relation to pH levels, students can add hydrated lime to samples of soil to increase the alkalinity. The Measuring Plant Growth resource offers suggestions for tracking and monitoring growth.
• To explore processes for helping to reduce pH levels in soil, students can create alkaline soil (adding hydrated lime, for example) and then experiment with various additives, including gypsum, to see what solutions are possible, how much of a substance it takes to make a measurable difference in pH, and what the cost factor might be when considered on a large scale, like a farm.

For all of these projects, a pH soil testing kit, available at garden stores or at Amazon.com, will be useful.

The deadline has passed for entering the Chemical Heritage Foundation's "It's Elemental" video contest, but voting is underway!

In recognition of the2011 International Year of Chemistry, the Chemical Heritage Foundation invited students to submit videos about the elements of the periodic table. Click an element from the chart to see the videos students created—and to learn more about a specific element. You'll find video coverage of familiar and favorite elements, like Hydrogen, Helium, Tungsten, and Phosphorous, but you'll also get a fresh on-the-screen look at elements that might be less familiar, like Tantalum, Cesium, and Rubidium.

Be sure and "vote" for the ones you like!

Be a Part of the International Year of Chemistry

The theme of the 2011 IYC is: "Chemistry—our life, our future." Now is a perfect time to explore Science Buddies' chemistry Project Ideas.

Parents: There are many chemistry project ideas in the Science Buddies directory of Project Ideas that can be done at home as a family project! You can explore our list of suggest "at home" projects here. Here are a few sample projects that you can have fun doing with your students: Cabbage Chemistry, Bubble-ology, and A Soluble Separation Solution.

If you use the Science Buddies website and are participating in one of the following California science fairs, please leave a "comment" (below) or email us at SciBuddy@sciencebuddies.org:

We are hoping to talk to students at these fairs, especially students who are presenting projects from the Science Buddies library of Project Ideas!

• San Mateo Science, Math, & Technology Fair
• San Francisco Middle School Science Fair
• Sciencepalooza!
• Marin County Secondary Science Fair
• Synopsys Silicon Valley Science & Technology Challenge
• Santa Cruz County Science Fair
• Sacramento Regional Science & Engineering Fair
• Tri-Valley Science and Engineering Fair
• Monterey County Science and Engineering Fair
• San Francisco Bay Area Science Fair

Good luck to everyone who is participating in a science fair in the coming weeks!

Your plants may appear to be still, but they are actually constantly in motion! Their movements are just very slow, and it can be easy to overlook what might amount to very small changes and adjustments in angle or direction. (Image source: Wikipedia)

You probably know that plants grow "toward" the light, and by experimenting with the placement of a plant in relation to its light source, you can "see" the plant "bend" toward the light. Such plants are phototropic. Tropisms are directional movements of plants in response to different kinds of stimuli. For example, a plant might respond to gravity (gravitropism), or water (hydrotropism), or touch (thigmotropism), or light (phototropism). Some plants respond to all of these, often at the same time!

Smarter Gardening

Learning more about tropisms and how they will impact the growth of certain plants in a garden can help you make choices in terms of both garden design (where should you put each plant?) and maintenance (do you need to add supports?). The choices you make based on the science behind plant behavior can increase the success and heartiness of your plants. For example, you want to be prepared to stake plants that will grow upwards towards the sun so that their stems can support their height. Plants that wrap around other things or curl up in response to touch may also need to be staked. And understanding the spatial requirements of a sun-tracking plant like the sunflower will help you make smart choices when you decide where, and how far apart, to plant them.

Digging Deep

The following Science Buddies Project Ideas let you roll up your sleeves and explore tropisms and the ways in which plants "move" in response to changes in stimuli. Variations at the end of each project offer ways to customize and alter the projects, so there is plenty of opportunity to create your own version of a tropism-based project!

• Plants Are On the Move! Experiments with Gravitropism: Use time-lapse photography to study gravitropism in Coleus plants. (Difficulty: 3)
• How Do Roots Grow When the Direction of Gravity Changes?: Repeatedly rotate growing rootlets and watch their attempts to track the shifting gravitational force. (Difficulty: 4-8)
• Plants On the Move! Experiments with Phototropism: Investigate how different quantities of light affect a plant's phototropic response. (Difficulty: 6)
• How Vines Find Their Spines: Thigmotropism in Morning Glory Tendrils: Explore the way a morning glory's tendrils "curl" in response to touch. (Difficulty: 7-9)

• Build Your Own Helio Tracker: Observe sun tracking with a mechanical version of a sunflower. (Perfect if your "green" thumb is a bit "brown"!) (Difficulty: 9)

What would you have made Watson "look like"? Check out IBM's video coverage of what was involved in giving Watson both a "face" and a "voice" for the Jeopardy! Competition.

Jeopardy! fans will be tuning in February 14-16 to see IBM's computer contestant, Watson, face off against the brain-power, trivia recall, and quick (thumb) reflexes of two of Jeopardy's all-time top winners, Ken Jennings and Brad Rutter. Jennings holds the record for the longest winning streak with 74 consecutive wins. Rutter, on the other hand, holds the record for the most winnings, more than $3.2 million.

These two champions will compete against... the world of artificial intelligence and a computer named Watson.

AI Déjà vu?

If you're a chess buff, this whole scenario might sound familiar, minus Alex Trebek. In 1997, another IBM computer, Deep Blue, took on Garry Kasparov, a world chess champion. The computer won.

Teaching a computer to play chess, however, and teaching a computer to understand the kinds of word-play and linguistic subtleties that are often involved in figuring out Jeopardy questions may be like comparing apples and oranges. A computer can draw upon all its data regarding chess moves and strategies and games played in the past in order to plan its next move. But while Watson is loaded up with a "world" of data (millions of pages of facts about every imaginable topic), Watson may or may not "get the joke" or be able to sift through all that information to offer the "right" succinct answer in the form of a question.

Don't be fooled by the fact that the on-screen virtual contestant will be represented by a digital image "standing" behind the middle podium between Jennings and Rutter. Watson's got serious data power behind it—a backstage block of computers that reportedly occupy the space of about ten refrigerators. (Watson will not be connected to the Internet, however. All three contestants will play with "what they know.")

We'll be watching to see how the past champs measure up against Watson.
It could, indeed, be a true "Daily Double" for artificial intelligence!

Game On

While programming a computer to test a Sudoku solution is a good introduction to programming, is fun, and is useful, it's not the same as teaching a computer to think for itself. The Artificial Intelligence: Teaching the Computer to Play Tic-Tac-Toe Science Buddies Project Idea lets you put a toe in the water in terms of teaching a computer to play games. And, luckily, there's no money at stake! (Difficulty: 6-8)

Read more pre-match coverage:

• A.I. expert Ray Kurzweil picks computer in 'Jeopardy' match (USA Today)
  
• On 'Jeopardy!' It's Man Vs. This Machine (NPR)
  
• A Fight to Win the Future: Computers vs. Humans (New York Times)
  

Interested in who and what was involved in building and teaching Watson? Find out more about the computer software engineer career path.

Static electricity can make your hair stand on end. Source: Chris Darling, Wikpedia

Ahhh.... winter. Snowpeople. Snowy days home from school. Hats, mittens, and scarves. Hot chocolate. And static electricity. Zap!

That's right, it's during the winter months that you are most likely to shock yourself on a door knob or when opening the refrigerator. And when you pull off your hat or pull on a sweater, your hair might just stand on end. Boing!

After getting zapped ten or a hundred times, you probably have learned to instinctively touch something as an intermediary first before grabbing a potential "shocker." But have you stopped to think about "why" you get shocked? And why things seem more "shocking" when it's cold outside?

It's not just winter doldrums at work—although if you scuff your feet across the carpet more in winter months, you certainly are upping your odds of a zinger of a zap. The reason winter days are more shock-prone than the lazy days of summer has to do with the level of moisture in the air. In the winter, more static electricity builds up in our homes because the heaters are on, which sucks moisture out of the air. In the summer, water in the air can help dissipate the electrons that we pick up as we move around, but when the air is drier, the charge collects and clings to us, building up until... zap!

A "Charged" Environment

Static electricity isn't just a problem in the winter. The "charge" of atoms is constantly changing as materials and objects make contact and electrons are passed around (or donated). Which objects "donate" and which objects are more receptive depends on where the objects fall in the triboelectric series. The objects that gain electrons are negatively charged (because electrons themselves have negative charges), leaving the objects that donated the electrons positively charged. You may have heard that "opposites attract." When it comes to static electricity, it's totally true! When a positively charged object gets near a negatively charged object, there is a movement of electrons from the negatively charged object to the positively charged one. Zap! That flow of electrons is the "electricity" part of static electricity.

What materials surround you makes a difference in how much static electricity you encounter. If your room is carpeted, for example, you might get shocked more often than if your floors are bare. You may have been "shocked" going down a slide at a playground or emerged from a playground tunnel with your hair fully charged. If you've ever heard the crackle when a load of clothes is pulled out of a drier, you've heard static electricity. Drier sheets help eliminate that problem. But how? What you wear, too, makes a difference in how much static electricity builds up in and around you. You can get shocked at the grocery store, especially if you've been pushing a cart. And you might find that you're simply someone who seems to carry more of a charge than others!

Controlling the "Shock" Factor

Whether you want to get away from the "shock" if static electricity or find a way to control it, the following Science Buddies Project Ideas let you capitalize on the "charge" in these winter months as you explore, avoid, and even harness static electricity.

• Rubbing Up Against Static Electricity (Difficulty: 1) Explore how static electricity builds up and what the role of friction is in the process. Does the number of times you rub a balloon change the amount of static electricity created?
• How Do Different Materials React to Static Electricity? (Difficulty: 3)
  Build an electroscope to see how much static electricity is created by different types of materials. Are you more shock-resistant in cotton or fleece?
• Where There Is Charge, There Can Be Sparks! (Difficulty: 6)
  Using household materials, you can build a Leyden jar capacitor that will enable you to trap and store static electricity—it's a bit like storing lightning in a jar! For the Ben Franklin buff, there's a connection here. But there's also a connection to the kind of touch screen used in popular Apple® products like the iPhone^TM and the iPad^TM. (Tip: You'll need a different kind of stylus for an iPad than an older Nintendo DS.)
• Avoid the Shock of Shocks! Build Your Own Super-sensitive Electric Field Detector (Difficulty: 6-8)
  Using the super-sensitive charge detector you build in this project, you can sense invisible electric fields—before you walk into or touch them!

Getting Started

If you are just beginning to explore electricity and electronics projects, be sure and review the Science Buddies Electronics Primer before you begin for an introduction to common terms and an overview of using a multimeter and testing a circuit with a breadboard.