UV Rays Increase Intelligence

Who would have thought that UV rays may increase proficiency in school exams? What are UV rays anyway? UV stands for Ultraviolet light, which is an invisible light wave to humans, but can be seen by some insects such as the bumblebee. Ultraviolet light is part of the Electromagnetic Spectrum. You have already come into contact with this light wave.

UV rays are emitted from the sun and stars as part of cosmic radiation. Scientists like to study UV rays because it helpts to learn more about Cosmos. Some of the Ultraviolet rays are absorbed by the Earth's atmosphere, however many of them still make it through. UV rays travel at the speed of light, as do any other parts of the EM Spectrum. The frequencies[1] of UV rays range from 7.5×10^14 to 3×10^17 Hz, while the wavelength ranges from 4×10^−5 to 10^−7 cm. There are three regions of ultraviolet light: near (closest to visible light), far (most unknown), and extreme (closest to X-ray). The three regions have "different energies of ultraviolet radiation"[2]. The energy ranges from 3 to 10^3 eV, which makes it more energetic than visible light, and allows it to create more harm.

The effect of UV rays can be seen when every year people come back from vacations with a full-blown sunburn. The energy of the UV light allows it to break up molecules when absorbed by the skin. Also, it can penetrate deeper than visible light, which makes the damage more serious. If the UV rays damage the DNA of a skin cell, then it has the potential to cause melanoma[3], a very dangerous form of skin cancer, so people must wear sunscreen.

The same ability to break up molecules allows UV rays to not only harm, but to help with sanitation purposes. Water Coolers and Dispensers you can find in offices contain a UV sanitation filter system. This idea gives the basis for SODIS, a Swiss-water disinfection program used in many third world countries to provide water safe to drink[4]. In Tanzania, Ndolela Primary School has been using SODIS since 2006. They experienced fewer cases of diarrhea, which increased attendance at the school. In return, the percentage of students passing the 6th Grade Exam increased from 15% to 95%. This is how UV rays helped with proficiencies at this school.


Photo Credit: NASA
National Cancer Institute

References:
1. Eberhard Sengpiel, Sengpielaudio Search Engine, Calculator - Wavelengths, 2. Radio waves and Light waves in a vacuum

2. Ruth Netting, NASA, The Electromagnetic Spectrum

3. National Cancer Institute, Melanoma

4. Mark Jenkins, National Geographic Water April 2010 Issue, Energy

Messengers from the Cosmos: Cosmic Radiation

Cosmic radiation is many different types of radiation from many different sources coming from cosmic objects. However, when most people speak of 'cosmic radiation' they are referring to cosmic background radiation, which is an electromagnetic radiation that originates from about 200,000 years after the big bang. The cosmic background radiation[1] (CMB) is detected as a black body radiation[2] of 2.7 Kelvins. Therefore, CMB covers a wide spectrum of frequencies and wavelengths. The maximum amplitude corresponds to a wavelength of 2 mm and a frequency of 150 GHz. The CMB is absorbed by conductive materials, and creates heat, just like a microwave does, except it's much weaker. CMB has very low energy, so it does not present any hazards to humans. An interesting fact about CMB is how uniform it is from all directions. Satelites that measure CMB, detect changes of 0.01% in CMB's intensity, in order to create cosmic background radiation maps.

Photo credit: NASA WMAP

We can classify cosmic radiation based on its source: the sun, stars, and accretion discs of black holes. Cosmic radiation can be electromagnetic waves or high-energy particles[3] (electrons and protons). Since cosmic radiation includes all bands found in the Electromagnetic Spectrum, it's important to know that much of the high-energy radiation is absorbed by Earth's atmosphere. Some ultraviolet light emitted by the Sun, that is not absorbed can reach Earth's surface. The near ultraviolet radiation has a frequency range of 1 PHz to 3 PHz, corresponding to a wavelength of 300 nm to 100 nm. These rays are harmful to humans because they cause skin cancer, so people should wear sunscreen. The UV rays interact with matter by modifying molecules and causing chemical changes.

The most important part of cosmic radiation is the sunlight. The sunlight has a profound effect on life on Earth. The visible light's (visible to humans) frequency range is 790 THz to 400 THz, while the wavelength ranges from 380 nm to 760 nm. Visible light provides energy for plants to do photosynthesis and be able to grow. It also can be utilized to create clean energy using solar panels.

Photo credit: OKsolar.com

High-energy electromagnetic radiation (X-ray and gamma-ray) are absorbed by the atmosphere, but they present danger to astronauts. The frequency range of X-ray is 30 PHz to 30,000 PHz, and the wavelength is 10 nm to 1 pm. The frequency range of Gamma-rays start at 30,000 PHz and there is no end. Therefore any Electromagnetic wave with a wavelength less than 1 pm is a Gamma-ray.

Electromagnetic waves of the cosmic radiation are discussed above. However, there are particles that also make up cosmic radiation that were not researched. Due to the multitude of Electromagnetic wave sources that produce cosmic radiation, the frequency and wavelengths cover a very wide range. Some sources like CMB are continuous, with very little change in their power density. Others, like Gamma-ray bursts are highly transcient. There are several month-long gaps separating a few seconds of high-energy bursts. This is why generic properties of the EM spectrum cannot be specified for the entire cosmic radiation, only different parts of it (like CMB).



References:
1. G. F. Smoot and D. Scott, http://pdg.lbl.gov/2000/microwaverppbook.pdf, 19. Cosmic Background Radiation

2. Dr. Seti, http://www.setileague.org/askdr/backgrnd.htm, Frequency of the Cosmic Background

3. Brent Nelson, M.A. Physics, Ph.D. Student, UC Berkeley, http://www.physlink.com/Education/AskExperts/ae254.cfm?CFID=27071600&CFTOKEN=7ada1b628d936e8d-9CD1BC03-15C5-EE01-B9386A09AF12FF96, What is cosmic radiation? Is it dangerous?

Veterinarians Don't Just Save Animals, They help People too

picture from: UCDavis

If I were a scientist, I would be a veterinarian. Veterinarians study animals and their treatments. They take care of pets, livestock, and animals at zoos or racetracks. A vet must graduate from an accredited college of veterinary medicine, and receive a State License (taken from the United States Department of Labor). Veterinarians vaccinate against diseases. Vets can also be involved with finding diseases like E. Coli in foods. Veterinary research may contribute to helping cure human diseases.

I chose this field of science because I love animals. Whenever I see an injured animal on the road or in the forest, I always want to help it. This job would allow me to save the animal if he can be saved, and comfort the animal’s family. Also, last year I shadowed my dog’s veterinarian and I really liked what she did the entire day. She examined animals and also spent time with them, like taking them out on walks. She also dealt with people, which is another aspect of the career that I like. There was a lot of lab work throughout the day. In my opinion, that makes the job more interesting because the vet has to figure out the virus or bacteria that is causing the problem.

My goal is to help people and animals through my work. Working as a veterinarian would allow this to come true. I also would like to have a Ph.D, which is sometimes necessary in this career. This job is also one that is always needed. It would be easy to keep a job if the economy goes bad because people always want to help their animals. This job is also important because of its legacy. Many cures for animal diseases can be used on humans too; it can also help with cloning. I am a visual learner, so this profession would be good for my learning style. There are many diagrams for body parts of animals to look at and learn, and I could color code medicines in order to learn them.

Coal Ash: 130 million tons of waste

To learn more about coal ash and its dangers, visit CBS news and watch 60 minutes. Here's the link: http://www.cbsnews.com/video/watch/?id=5362297n

There are some advertisements randomlly through the video so be patient.

Good Old Coal, but is it dangerous?

The myth whether coal power plants are more radioactive than nuclear power plants exists for two reasons; on one hand, everyone knows nuclear power plants are radioactive. On the other hand, coal was used before radioactivity was discovered, so people don’t associate coal to radioactivity. Also, in movies, nuclear power plants are the ones that blow up. The accident at Chernobyl nuclear power plant in 1986 also reinforced the fear of radiation exposure. It is due to extensive media coverage that people only think of a nuclear power plant as a source of radioactivity.

Coal’s content of uranium and thorium makes it radioactive since both of these elements are radioactive. When coal burns into fly ash, the radioactive materials are concentrated up 10 times their original levels. According to Scientific American, the coal fly ash deposited within 0.5 to 1 mile from the smoke stack carries 100 times more radiation into the environment than a nuclear power plant providing the same amount of energy, as long as there are no accidents. If the radiation of levels of the complete nuclear fuel cycle, including mining and waste disposal, is considered, coal is still more radioactive than nuclear, but only 3 times. It is necessary to mention that the radiation from even the coal power plants is much less than the naturally occurring radiation.
Scientific American disproves this myth. According to measurements referred to in the article, coal power plants emit more radioactive materials than nuclear power plants. The Oak Ridge National Laboratory also disproves this myth.

The article of J. B. McBride, a scientific researcher, brings detailed calculations of how much radiating material is emitted from coal in the U.S. and the world. He doesn’t take a side in presenting supporting data; therefore, his opinion seems objective. For these reasons, the evidence that coal power plants are more radioactive than nuclear power plants is reliable.

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