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Brainstorm!. Things that are too small to see:. Engineering to Reduce the Germs!. How Small Am I?. Order the cards from largest to smallest. Wavelength of red light. Wavelength of UV light. MRSA. Introduction to Bacteria.
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Brainstorm! Things that are too small to see:
How Small Am I? Order the cards from largest to smallest Wavelength of red light Wavelength of UV light
Introduction to Bacteria Slide 5: United Streaming video clip Life Science: Bacteria “Infectious Diseases Caused by Bacteria” http://player.discoveryeducation.com/index.cfm?guidAssetId=BD07D5B2-DAA1-476E-B59D-E6A4F5A98631&blnFromSearch=1&productcode=US
Highlights of Bacteria: • Smallest of free living organisms • You can squeeze a million of them on the head of a pin! • Live in our skin, intestines, nose & throat • Control every major function in our world • Cycle nutrients • Produce antibiotics • Keep us healthy • Make us sick
Virginia Headlines! “A county in southern Virginia closed its 21 schools on Wednesday to clean them to prevent the spread of a dangerous bacterial infection that killed a 17-year-old high school student, officials said.” (Reulters) MRSA! Methicillin-Resistant Staphylococcus aureus
Introducing The Super BugMRSA! • Commonly found on the skin or in the nose of healthy people. • Over the years bacteria have become resistant to various antibiotics. • MRSA can be transmitted from person to person through close contact. • Skin-to-skin contact when there is a scratch or opening in the skin • Sharing contaminated personal items • Poor personal hygiene • Direct contact with contaminated environmental surfaces • Living in crowded settings
That brings us toThe science of VERY small things . . . NANOSCIENCE!
Engineers Look at Surface Properties • Is it smooth or rough? • Is it sticky or non-sticky?
What about the properties of surfaces make them harbor bacteria?
EXPERIMENT! Compare surfaces! Reach out and touch! • Wood • Glass • Plastic
Which one is easier to clean? Did you notice that the surfaces have a different properties? Which one is the roughest? Wood Plastic Glass
Take a Look at Why it is the Roughest. . . Wood Under a Microscope! http://micro.magnet.fsu.edu/optics/intelplay/gallery/reflectedbrightfield.html 10x magnification 60x magnification Wooden Toothpick 200x magnification
To Stick or Not to Stick? • Materials needed: • 4 grades of sandpaper • Bee Bees • Cornstarch • Salt • Water
Look familiar? MRSA
Check Out Your Own Hair • That’s pretty small, right? • This is a nanowire wrapped around a strand of human hair.
Engineering Challenge! • What surface in your school is most prone to harbor bacteria? • Design a toilet that is less likely to accumulate and shelter bacteria.
Get to Work! • You have 3 minutes to work in a small group to design the new toilet seat • Keep in mind what we have discussed about surface properties • Don’t worry about the cost of materials • Then we will share our designs
Sani-Seathttp://www.cleanseats.com/toilet_seats/view/video.htmlSani-Seathttp://www.cleanseats.com/toilet_seats/view/video.html
What do we need to know about surfaces on the nano level? • That bacteria can be spread through touch • Different surfaces can be smooth or rough; the rougher surfaces are the more bacteria they will hold • When we design a product we need to reduce the spread of germs. • How can be do that? By using an ultra-smooth surface or by not touching the surface at all!
Credits • Slides 3 & 4: Refer to (PDF) What Is Nanotechnology? By Anna M. Waldron and Carl A. Batthttp://www.itsananoworld.org/; note the addition of the picture of MRSA found at http://www.righthealth.com • Slide 5: United Streaming video clip Life Science: Bacteria “Infectious Diseases Caused by Bacteria” http://player.discoveryeducation.com/index.cfm?guidAssetId=BD07D5B2-DAA1-476E-B59D-E6A4F5A98631&blnFromSearch=1&productcode=US • Slides 7: Quote taken from Reuter’s article at http://www.reuters.com/article/domesticNews/idUSN1729913920071017 • Slide 6 & 8: data from United Streaming video clip Life Science: Bacteria “Introduction to Bacteria” (02:32) • Slide 9: http://www.animationfactory.com/en/ • Slides 14 & 15: data from NSTA 2008 Boston Conference; Foundations of Nanoscale Science: Building an Interactive Program to Foster and Assess Learning of Nanoscale Science Concepts Clara Cahill and Cesar Delgado • Slide 16: images of wooden toothpick at various magnifications http://micro.magnet.fsu.edu/optics/intelplay/gallery/reflectedbrightfield.html • Slide 17 & 19: Adapted from NSTA 2008 Boston Conference; Foundations of Nanoscale Science: Building an Interactive Program to Foster and Assess Learning of Nanoscale Science Concepts Clara Cahill and Cesar Delgado • Slide 18: Refer to (PDF) What Is Nanotechnology? By Anna M. Waldron and Carl A. Batt http://www.itsananoworld.org/; note the addition of the picture of MRSA found at http://www.righthealth.com • Slide 19: Image from NSTA 2008 Boston Conference; Foundations of Nanoscale Science: Building an Interactive Program to Foster and Assess Learning of Nanoscale Science Concepts Clara Cahill and Cesar Delgado • Slides 20, 21, & 24: Adapted from NSTA 2008 Boston Conference; Foundations of Nanoscale Science: Building an Interactive Program to Foster and Assess Learning of Nanoscale Science Concepts Clara Cahill and Cesar Delgado • Slide 23:Video clip from Sani-Seat at http://www.cleanseats.com/toilet_seats/view/video.html
Just How Small Is “Nano”? • A football field simulates magnifying the world by 1 million times. • At this scale . . .the thickness of a hair would be the width of the field. • A red blood cell would be 10 meters. • A staph bacterium would be just 1 meter wide. • One nanometer would be just 1 mm!