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Mar022012
POSTED AT 09:07 PM
Before you read this blog entry, watch this video: http://www.youtube.com/watch?v=IqK2r5bPFTM&feature=related This video footage shows the Tacoma Narrows Bridge, a suspension bridge built over Puget Sound in Washington state in 1940. At the time it was the third longest suspension bridge in the world. From the beginning, the bridge swayed dramatically in even mild wind, rocking from side to side. The bridge finally collapsed a little over four months from when it opened. The video you watched was taken on the day the bridge collapsed; can you believe that people actually drove across the bridge when it was buckling like that? Apparently, when driving across, cars coming from the other direction would appear to be riding waves as they approached. Locals were told that the bridge was massive enough to keep it from collapsing and it was affectionately called "Galloping Gertie." Fortunately, no people died in the bridge collapse.  Why did the bridge collapse? It seems that the design of the bridge diverted wind above and below the roadbed. The shape of the roadbed created an aerofoil (a wing shape) that created lift beneath the roadbed and drag above it. The aerodynamics and the flexibility of the bridge combined so that the deck was lifted up and down over and over. Originally the bridge was supposed to have trusses underneath the roadbed which would have allowed the wind to pass through without creating an aerofoil. If the bridge was built using this original design (shown below) would probably still be standing today. 
Jan292012
POSTED AT 05:08 PM
 Energy drinks: They’ve got cool names and marketing campaigns. I often see students wearing t-shirts that advertise the products, and when I ask why they are wearing it, students tell me that they think that the shirt is cool, or that they wear it because it is associated with a sport, a famous athlete or other activity that they admire or enjoy. The energy drink companies endorse athletes and their sporting events, and they sponsor music events and festivals, which further adds to their appeal to young people.
What all energy drinks have in common is their classification as a beverage that supposedly supplies energy. What is energy? In purely scientific terms, energy is defined as the ability to do work. For animals like humans, this ability comes from food. Food has stored, or potential, energy because animals’ bodies can break down the molecules to release energy (Energy, 1). In energy drinks, the only ingredient that provides this chemical energy is sugar. Sugar free energy drinks don’t have any calories, and therefore don’t supply chemical energy. Regular soda, juice, sports drinks, milk and other drinks with sugar (milk has lactose, or milk sugar), also supply this type of chemical energy for a quick pick-me-up (Watson, 1).
Why, then, do energy drink companies claim that their beverages provide more energy than other drinks? The answer lies in the rest of the ingredients in their products. The first added ingredient is caffeine. Many sodas also have caffeine, but the average amount in a typical soda is about 18 to 48 milligrams of caffeine per 12-ounce serving. In contrast, energy drinks can have from 160 milligrams to 344 milligrams per 16-ounce can (Norwood, 1), and additional caffeine can come from unregulated ingredients like guarana, kola nut, yerba mate, and cocoa (Hitt, 1).
Caffeine is a drug that acts as a stimulant to the nervous system. The caffeine molecule blocks the breakdown of a particular messenger chemical, called cAMP, that is eventually responsible for raising the heart rate, creating more blood flow, higher blood pressure, and delivering more oxygen to the brain and other tissues. When cAMP is active, it makes an animal feel more alert and ready to react (Smatresk, 1). However, when caffeine blocks the breakdown of cAMP, it keeps the body in this constant state of readiness and can put undo stress on the heart and other tissues. Caffeine also acts as a diuretic, meaning that it causes the kidneys to release extra fluid into urine, which could cause dehydration. In addition, caffeine is an addictive drug, so once the body gets used to a certain level, it becomes difficult to cut down or eliminate it from the diet (Watson, 1). Part of the problem with energy drinks, however, is that there are other ingredients that may interact with caffeine to produce dangerous effects. Other ingredients in energy drinks include: · “Ephedrine - A stimulant that works on the central nervous system. It is a common ingredient in weight-loss products and decongestants, but there have been concerns about its effects on the heart. · Taurine - A natural amino acid produced by the body that helps regulate heart beat and muscle contractions. Many health experts aren't sure what effect it has as a drink additive (and the rumor that taurine comes from bull testicles is false). · Ginseng - A root believed by some to have several medicinal properties, including reducing stress and boosting energy levels. · B-vitamins - A group of vitamins that can convert sugar to energy and improve muscle tone. · Guarana seed - A stimulant that comes from a small shrub native to Venezuela and Brazil. · Carnitine - An amino acid that plays a role in fatty acid metabolism. · Creatine - An organic acid that helps supply energy for muscle contractions. · Inositol - A member of the vitamin B complex (not a vitamin itself, because the human body can synthesize it) that helps relay messages within cells in the body. · Ginkgo biloba - Made from the seeds of the ginkgo biloba tree, thought to enhance memory” (Watson, 1). The effects of many of these supplements remain untested and unknown. Their potential interactions with each other and with caffeine also are unknown, and there is no known safe dose for many of these additives (Hitt, 1). Some drinks contain more than 4000 percent of the recommended daily allowance for vitamin B-12 (Severson, 1). The effects can be deadly.
Just last month, on December 17, 2011, fourteen-year-old Anais Fournier went into cardiac arrest after drinking two energy drinks. She died six days later; the cause of death was found to be caffeine toxicity. Doctors and medical examiners could find no other cause of death, no other reason that a healthy teenager would have a heart attack (Bonura, 1). Anais is pictured at right.  In 2007, 5448 reports of caffeine overdose were reported. 46%, or 2506, were in people under the age of 19 (Hitt, 1). Symptoms of caffeine overdose include, “liver damage, kidney failure, respiratory disorders, agitation, confusion, seizures, psychotic conditions, nausea, vomiting, abdominal pain, rhabdomyolysis, tachycardia, cardiac dysrhythmias, hypertension, myocardial infarction, heart failure, and death” (Hitt, 1).
Anais’ family and boyfriend plan to honor her memory by working to have the sale of energy drinks regulated by the United States Food and Drug Administration. Because they are categorized as dietary supplements, there are no regulations in place to control the amount of caffeine in the drinks or to regulate their sales.
Works Cited Bonura, Denise. "Caffeine Toxicity from Energy Drinks Cited in Anais Fournier's Death - Waynesboro, PA - Waynesboro Record Herald." The Record Herald. Waynesboro Record Herald, 26 Jan. 2012. Web. 29 Jan. 2012. <http://www.therecordherald.com/news/x364060147/Caffeine-toxicity-from-energy-drinks-cited-in-Anais-Fourniers-death>. ""Energy"" HowStuffWorks "Learn How Everything Works!" How Stuff Works, Inc., 2012. Web. 29 Jan. 2012. <http://www.howstuffworks.com/environmental/energy/energy-info.htm>. Hitt, Emma. "Energy Drinks Pose Serious Health Risks for Young People." Medscape News Today. Medscape Medical News, 14 Feb. 2011. Web. 29 Jan. 2012. <http://www.medscape.com/viewarticle/737311>. Norwood, Robyn. "Young Athletes, Energy Drinks: A Bad Mix? USATODAY.com." USA Today. Gannett Company, Inc., 5 Dec. 2011. Web. 29 Jan. 2012. <http://www.usatoday.com/sports/story/2011-12-01/young-athletes-and-energy-drinks-a-bad-mix/51556148/1>. Severson, Kim. "Energy Drinks Are Fueling Concerns - New York Times." The New York Times - Breaking News, World News & Multimedia. New York Times Company, 19 June 2006. Web. 29 Jan. 2012. <http://www.nytimes.com/2006/06/19/health/healthspecial/19drinks.html?pagewanted=all>. Smatresk, Neal J. "How Does Caffeine Affect the Body?" Scientific American. Scientific American, Inc., 15 Feb. 1999. Web. 29 Jan. 2012. <http://www.scientificamerican.com/article.cfm?id=how-does-caffeine-affect>. Watson, Stephanie. ""How Do Energy Drinks Work?"" "How Do Energy Drinks Work?"How Stuff Works, Inc., 2012. Web. 29 Jan. 2012. <http://science.howstuffworks.com/innovation/edible-innovations/energy-drink.htm>.
Sep052011
POSTED AT 02:00 PM
I am over-the-top excited because we just got approval to participate in ANOTHER citizen science project called the Mastodon Matrix Project! I found it while I was writing the last blog entry, emailed them, and got a positive response this morning. In this project, we will be sent bags of 9,000+ year-old peat from New York State. This is the soil that was around a mastadon that was discovered in Hyde Park, NY in 1999. In our classes this winter, we will spend several class periods searching and sifting through the soil for fossils associated with the mastodon (hair, teeth, other organisms). We will record our findings and send everything back to The Paleontological Research Institution in Trumansburg, NY (Museum). Below are an artist's interpretation of a mastodon and some fossils:  I have found fossils in upstate New York, but they were mostly from 400,000,000 years ago, when NY was covered by a shallow sea. The mastodon was obviously found in rocks from a much more recent time period, the last Ice Age. I started thinking about what Massachusetts was like in the past. I already knew that much of our state is comprised of metamorphic rocks which have been squished and heated so that there are few fossils left. However, there are a few places in Massachusetts where fossils have been found. Below is a geologic map of Massachusetts showing the different ages of the rocks in our state.  See that area of green? That's the Connecticut River Valley, and it contains rocks from the Triassic and Jurassic Periods (about 250 to 150 million years ago--see geologic time scale, below) which have been the site of the discovery of many dinosaur footprints. If you go up to Hadley, Massachusetts (about 70 miles up Route 2), you can even see some of the tracks at , although most have been removed and placed in museums ( http://www.nashdinosaurtracks.com/index.html). Hadley is where the first dinosaur tracks were found. There is a really great place to visit called Dinosaur State Park in Connecticut ( http://www.dinosaurstatepark.org/) where there are literally thousands of dinosaur footprints still in the ground preserved under a dome for visitors to see. Below is one of the footprints found in Hadley. So, what types of prehistoric animals lived in Massachusetts? Here are a few: 1. Anchisaurus was a dinosaur that lived during the late Jurassic ( http://www.rareresource.com/anchisaurus.htm). 2. Podokesaurus, a dinosaur similar to Coelophysis, lived during the early Jurassic ( http://en.wikipedia.org/wiki/Podokesaurus). 3. Stegomosuchus was a small reptile (not a dinosaur) that was related to crocodiles ( http://en.wikipedia.org/wiki/Stegomosuchus). There were plenty of other organisms over billions of years, but Massachusetts has experienced a lot of metamorphic changes, which means that there aren't many fossils to be found. However, a few years ago, an important discovery was made in North Attleboro, MA. The world's oldest fossil of a flying insect was found behind a strip mall! There had never been a full-body impression found before. The insect, which lived about 300 million years ago, was about three inches long (Geologists). Other fossils found in Massachusetts have included trilobites, which were arthropods that lived beneath ancient seas hundreds of millions of years ago. The trilobites found in our state provide evidence that we were once connected to Africa and parts of Europe (Prehistoric 2011). Here is an artist's interpretation of what Jurassic Massachusetts may have looked like:
Sep032011
POSTED AT 06:55 PM
I spent a few hours today tying plastic strips on trees behind the middle school. Okay, you may be thinking, "My new 8th grade science teacher is weird", but actually I was setting up a fantastic new citizen science opportunity for our science classes! Citizen science is just what is sounds like; it is science done by...yes, citizens. Citizen science projects recruit thousands of people who don't necessarily work as professional scientists (although some may, I am sure) to gather data for scientific research projects. The idea is that this greatly increases the breadth and depth of the data that can be gathered, and it also avoids some of the financial difficulties that scientific investigations can experience. If you think about it, one scientists, or even one small team of scientists, can only be in so many places, and can only gather so much data, but if they get 1000s of people around the world to gather data for them, they create a much more powerful experiment. Our citizen science project is called Buds, Leaves, and Global Warming, and we will be helping out forest ecologist John O'Keefe, who is investigating whether or not the length of the growing season is changing due to global warming. Dr. O'Keefe works at the Harvard Forest, and studies a branch of biology called phenology, which is the study of the cycles found in nature. Examples of cycles includes the timing of migrations of animals, the mating seasons, and the appearance of pollen. In our project, we will be observing the color change of leaves in the fall and the emergence of buds in the spring. Each small group of students will be in charge of a single branch on a tree and will make observations four times in the fall and four times in the spring. We will be part of a larger group of elementary, middle and high schools gathering this information for Dr. O'Keefe. For more information on Buds, Leaves, and Global Warming, visit http://harvardforest.fas.harvard.edu/museum/phenology.html
Are you interested in doing citizen science on your own or with your friends and family? Visit The Network for Citizen Science ( http://scienceforcitizens.net/). There are many different projects that need our help, including monitoring hurricane and earthquake data, watching birds at feeders and squirrels in the yard, monitoring invasive crayfish in local waterways, monitoring air and water quality, and hundreds more. You can even try their "Project Finder" application to find one that interests you: http://www.scienceforcitizens.net/finder/.
Aug292011
POSTED AT 01:10 PM
Hurricane Irene is over now. Our family was lucky enough to get through it without even losing power. This morning, the day after, we have a lot of branches and leaves in our yard, but no trees fell in our immediate vicinity. When I woke up this morning, the first sounds I heard (instead of wind) were insects buzzing and birds singing, and I wondered to myself how they and other wildlife survived during the storm. I wonder if they know to hide somewhere, and where they could possibly hide that would be protected enough from the hurricane's winds. .jpg/236px-Hurricane_Irene_(1999).jpg) According to Birding.com (How Birds, 2011), birds can sense when a big storm is coming because they feel a change in barometric (aka air) pressure. When they feel a storm coming, some birds fly away from the path of the storm while others find a place to roost. One interesting fact that I learned is that birds have a different type of reflex that allows them to hang onto branches even when they are asleep. In fact, when a bird lands on a thin branch (or electrical wire), their muscles automatically tighten their toes around the perch. They actually cannot let go of their perch unless they deliberately unclench their feet; this is the opposite of what we would have to do. Other birds, like woodpeckers, hide in tree cavities during the storm. I found another article from six years ago (How wildlife, 2005) that describes some of the problems faced by wildlife during storms. Some aquatic creatures like oysters and fish can be totally wiped out in certain areas. Hurricane Hugo wiped out half of the population of endangered Puerto Rican parrot, because there weren't enough secure nesting spots available during the storm. However, the article goes on to say that it is rare that an animal or plant population is permanently damaged by a hurricane. It seems that most organisms that have survived in places where natural disasters periodically occur have evolved to be able to withstand them. When we study evolution, we look at the survival of populations or species rather than the survival of individuals. In fact, storms like Hurricane Irene act as filters in a way; the individuals that survive are usually those with the best adaptations for surviving the storm. For example, the birds and insects that have the instinct to find a safe place to ride out the storm are the ones that are most likely to survive and pass down their survival genes. The trees in the forest that survive the storm are the ones that are the strongest; their dead and/or diseased limbs have been pruned by the high winds and their sickly, weak neighbors have been felled. In this sense, then, a hurricane serves a purpose; it keeps the ecosystem and its populations strong for future generations. Below are some orphaned squirrels brought to a humane society after Hurricane Irene:
Aug282011
POSTED AT 05:17 PM
Apparently being out in nature makes us relax, feel calmer and even enhances learning. I'm sure that there are many people who would swear that this is true, but as a science teacher, I demand hard evidence. I just read an article on Science-a-Go-Go called "Soil bacterium enhances brain's ability to learn" (Melville, 2010) that describes research that shows that exposure to a bacterium called Mycobacterium vaccae increases levels of serotonin, which is a hormone that helps us to relax. The article suggests that this can be applied to teaching and learning; more time spent outside can help students to learn more.  To me, science is all about figuring out how the world works, and of course a lot of the world is outside. I went to a workshop last week where I learned how to get my students involved with citizen science, which is when everyday people collect data to contribute to scientific studies. I plan to bring my students outside this year to gather observations on the process of leaf drop in the fall and leaf budding in the spring. I figured that this experience would enhance their understanding of and appreciation for doing authentic science, but now it seems that just going outside and breathing the bacteria-laden air will help them to learn more! We all need to go out and roll around in the dirt before our next big test! I also wonder if there is any of this soil bacteria left on fresh vegetables that we eat; perhaps there is a link between eating home-grown vegetables and better learning.
Aug282011
POSTED AT 04:14 PM
I recently read an article on ScienceNews.org called "Young Elephant Struck by Idea" (Milius, 2011). The article tells about how an elephant in a zoo moved a cube in his enclosure to use it as a step stool to reach some dangling fruit. This was part of a larger experiment on elephant intelligence; the researcher was trying to see if elephants could use logical reasoning to figure out how to get fruit that was out of their reach. The youngest elephant in the enclosure was the only one who figured out how to use the step to get to the fruit, and none of the elephants used a stick provided to pull the fruit toward them.  One factor mentioned in the article is that the tools provided for the elephants aren't "elephant friendly". I think that this is a good point; since we aren't elephants, we really cannot judge their intelligence or lack of intelligence through our own, human point of view. We can't expect other animals to have the same type of intelligence that we have, for the simple reason that they aren't the same as us! However, if artistic ability or the desire to create art is a measure of intelligence, then elephants are quite smart. Apparently many elephants have been taught to paint: http://www.elephantartgallery.com/
I know that I have heard that elephants mourn their dead and that they can outwit farmers in their native countries. I did a search on "elephant intelligence" and I found another article called "Elephants Outwit Humans during Intelligence Test" on Discovery News (Viegas, 2011). This article describes how elephants work cooperatively to solve problems, come up with new approaches, and even cheat to get get what they want! I really believe that many humans have a built-in prejudice that doesn't allow them to believe in the intelligence of other animals unless they behave in a human way. However, these animals may have intelligence that is so alien to us that we don't recognize it. Even animals like octopuses have shown great intelligence by sneaking out of their tanks at night to get at food held in other tanks in a lab. They then return to their own tank to act innocent (Scigliano, 2003)! Just think of the behavior of your pets--how can you deny their intelligence? There are more smart organisms out there than we currently admit! Works Cited Milius, Susan. "Young Elephant Struck By Idea." Science News. Science News, 24 Aug. 2011. Web. 28 Aug. 2011. <http://www.sciencenews.org/view/generic/id/333634/title/Young_elephant_struck_by_idea>.
Scigliano, Eric. "Through the eye of an octopus." Discover Magazine. Kalmbach Publishing Co, 1 Oct. 2003. Web. 28 Aug. 2011. < http://discovermagazine.com/2003/oct/feateye>. Viegas, Jennifer. "Elephants outwit humans during intelligence test." Discovery News. Discovery, 7 Mar. 2011. Web. 28 Aug. 2011.< http://news.discovery.com/animals/elephants-intelligence-test-110307.html>.
Jan282011
POSTED AT 05:29 PM
This is a short entry so that you can make comments on the articles.
The first article is about how scientists found that the Egyptian jackal is more closely related to the North American gray wolf than it is related to African jackals like the golden jackal. This is interesting, because the two populations have been separated for a long time--how long ago were Africa and North America together in Pangaea? They started to separate during the early Jurassic--about 180 million years ago! So that means that there was a common ancestor to the Egyptian jackal and the gray wolf living in Pangaea 180,000,000 years ago.
By Mark KinverScience and environment reporter, BBC News
Below: The Egyptian jackal has now been renamed the Egyptian wolf!
The second article is related. This article explains that scientists intend to "catalog" all living organisms using a stretch of DNA that is different in every living thing. This catalog will serve as a database so that any organism can be identified by its DNA "barcode".
Science intends to tag all life
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By Jonathan Amos
BBC News science reporter
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Oct292010
POSTED AT 01:24 PM
Albinism
Albinism is a condition that is characterized by a lack of the pigment melanin in the hair, skin and eyes. Albinism follows a simple Mendelian pattern of inheritance; genotypes AA and Aa both result in normal melanin production because the individual has at least one copy of the working allele for melanin. If an individual receives two copies of the recessive allele (genotype aa), then they do not have a working copy of the gene that codes for melanin production and are therefore albino.
In humans, there are four different types of albinism, Type 1, Type 2, Type 3, and ocular albinism.
Type 1 occurs in 1 in every 40,000 births, and is usually characterized by a complete lack of pigment in the hair, skin and eyes. People with Type 1 albinism may be very sensitive to light, have poor eyesight and involuntary eye twitching. It is caused by a mutation in a gene found on Chromosome 11.
Type 2 is more common and occurs in 1 in every 15,000 people. People with this type of albinism may have some pigmentation, but not much. They may have similar eye problems as people with Type 1. Type 2 is caused by a mutation in a gene found on Chromosome 15.
Type 3 occurs at an unknown rate and is caused by a mutation in a gene found on Chromsome 9. It is only found in people who are of African descent. They are very light-skinned and may experience similar eye problems as those with Types 1 and 2.
Ocular albinism is caused by a mutation in a gene found on the X-chromosome, which means that this type of albinism is a sex-linked disorder. A female who gets one copy of the mutated form of the gene will not have ocular albinism; she has to get two copies, one from each parent. A male child, however, gets only one X chromosome, and therefore will have ocular albinism when he gets one copy of the mutated allele. Ocular albinism only affects the pigmentation in the eyes, so that they are not pigmented. People with ocular albinism have poor vision and often have involuntary eye twitches.
The appearance of albinos is striking; albinos have no pigment in their hair, eyes, and skin, and therefore are white in color. Because the irises of their eyes have no coloring, the color of the blood in the blood vessels shows through and the eyes appear pink. Because of the lack of protective pigment in their skin, albinos are more susceptible to skin cancer. Lack of pigmentation in the retina causes vision problems that cannot be corrected with glasses, and many albinos are considered legally blind.
Albinism occurs in nearly all animals. There are albino humans, gorillas, dolphins, alligators, lobsters, koalas…you name it! Of course there are also albino Paper Pets!
   
   
 
Jul082010
POSTED AT 08:42 AM
1st section: Introduction
Since we are a soccer family, we have been avidly watching the World Cup games this month, and since I am a science teacher, I received an email yesterday about the physics of soccer. Apparently there was some controversy about the design of the 2010 World Cup Soccer Ball. Designed by Adidas, it is supposed to be the roundest ball "ever", and has small ridges and grooves to provide friction for grip by hands (goalies) and feet (field players). However, the players have been reporting that the design makes the ball unpredictable in the air and creates difficulty for defenders and keepers.
The science behind the movement of any spherical object in the air is something called the Magnus effect. Usually, when the soccer ball is kicked, it both travels forward, in the direction of the kick and spins as it travels. The reason it spins is because it is usually not kicked exactly in the center. If the ball is kicked slightly to the left of center, it will then spin in a clockwise direction. The spinning of the ball changes the air flow over the surface of the ball. On the side of the ball where the air from the spinning and the air from the ball moving forward are moving in the same direction, the air pressure against the ball is less than on the other side. This creates a lift from the area of higher pressure towards the area of lower pressure. This phenomenon is called the Magnus effect. The problem with the new ball seems to be that the grooves and ridges disrupt the air flow over the ball and cause the ball to behave unpredictably.
2nd Section: My thoughts, ideas and questions
I thought that this information was interesting. I know that when I watch my kids play soccer, sometimes the ball seems to bounce higher or more erratically or even to shift direction in the air. I think that there must be a lot of different variables that affect the ball's behavior though. The different types of fields, whether the grass has been cut recently, the wetness of the ground, and the inflation of the ball must all be factors. I figure that the air temperature and air pressure must also affect the bouncing of the ball, and the wind affects the movement in the air. However, most of these variables are controlled in the World Cup games, and there may be some scientific truth behind the observations of the players, who after all, have played hundreds, if not thousands, of soccer games. One other factor that has been blamed is the altitude (5000 feet) at which the World Cup games have been played. This changes the air pressure, which could affect the bounce of the ball. However, this does not account for the strange shifts in the air. For that, we may need to look at the Magnus effect.
See:
http://www.cnn.com/2010/SPORT/football/06/02/football.jabulani.ball.world.cup/index.html
http://www.npr.org/templates/story/story.php?storyId=127839848&ps=cprs
http://serioussoccer.net/Documents/PhysicsofSoccer.pdf
http://www.soccerballworld.com/Spinning_Ball.htm
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