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Introduction
Summarization of "How to go to space, without having to go to space"
Nuclear Physics
Astronomy
The Nature of Light
Hefur geislun frá fartölvum sem menn sitja oft með í kjöltunni einhver skaðleg áhrif á líkamann?
Does radiation from laptop which people sit commonly with on their lap any damaging effects to your body?
Electromagnetic radiation from a laptop, like when it‘s connected to wireless internet, has quite low frequency and moves little energy, less than the radiation from cellphones and multiple times less than, for example X-Ray radiation. In studies on the effects of electromagnetic fields on cells, including sperm, people have reported changes on their behaviour and on their activity in lab glasses (also known as vitro) but it doesn‘t demonstrate the effect of electromagnetic fields on men. It explains how many other things in the enviroment can have the same or similar symptoms. You should also have in mind that electromagnetic radiation from various kinds of sources is very common in our enviroment. There are some examples that the heat from a laptop when resting on our thighs has cause some damage on skin and permanent erythroderma, which is a skin disease. That kind of skin disease comes with prolonged heat which isn‘t hot enough to cause our skin to burn. As a final note, it‘s good to know that increases in temperature can have bad effects on sperm population.
It wasn't tough at all translating the text from Icelandic to English because the vocabulary there was something I have already learned through past English classes. Things like X-ray radiation, vitro, erythroderma and electromagnetic were the toughest one to translate but it didn't take a long time to do it.
Summarization of "What we can learn from galaxies far, far away"
The experimental strontium lattice clock
As described in Nature Communications, the experimental strontium lattice clock at JILA, a joint institute of NIST and the University of Colorado Boulder, is now more than three times as precise as it was last year, when it set the previous world record. Precision refers to how closely the clock approaches the true resonant frequency at which the strontium atoms oscillate between two electronic energy levels. The clock's stability -- how closely each tick matches every other tick -- also has been improved by almost 50 percent, another world record.
The JILA clock is now good enough to measure tiny changes in the passage of time and the force of gravity at slightly different heights. Einstein predicted these effects in his theories of relativity, which mean, among other things, that clocks tick faster at higher elevations. Many scientists have demonstrated this, but with less sensitive techniques.
"Our performance means that we can measure the gravitational shift when you raise the clock just 2 centimeters on the Earth's surface," JILA/NIST Fellow Jun Ye says. "I think we are getting really close to being useful for relativistic geodesy."
Relativistic geodesy is the idea of using a network of clocks as gravity sensors to make precise 3D measurements of the shape of Earth. Ye agrees with other experts that, when clocks can detect a gravitational shift at 1 centimeter differences in height -- just a tad better than current performance -- they could be used to achieve more frequent geodetic updates than are possible with conventional technologies such as tidal gauges and gravimeters.
To help measure and maintain the atoms' thermal environment, NIST's Wes Tew and Greg Strouse calibrated two platinum resistance thermometers, which were installed in the clock's vacuum chamber in Colorado. Researchers also built a radiation shield to surround the atom chamber, which allowed clock operation at room temperature rather than much colder, cryogenic temperatures.
You can read more about it at http://www.sciencedaily.com/releases/2015/04/150421132031.htm
Tilrauna strontíngrindklukkan
„Okkar framkvæmd þýðir að við getum mælt sérstakt ferli þar sem rafsegulgeislun er upprunnin frá uppsprettu þar sem þyngdarsvið er minnkað í tíðni þegar það er skoðað í svæði sem er veikara en þyngdarsviðið sjálft (í.ö.o. kallað þyngdaraflsferlið), þegar hækkað er klukkuna um 2 sentimetra á yfirborði jarðar,“ segir JILA/NIST Fellow Jun Ye. „Ég held að við séum að komast mjög nálægt því að vera gagnleg fyrir relativistic landmælingar.“ Relativistic landmælingar er sá hugmynd um að nota hóp af klukkum sem þyngdaraflskynjara til þess að gera nákvæmnar 3D mælingar af lögun jarðar. Fellow Jun Ye er sammála öðrum sérfræðingum að, þegar klukkur geta greint þyngdaraflsferlið þegar það er 1 sentímeter munur á hæð – bara réttsvo betra en núverandi árangur – gætu klukkurnar verið notaðar til að ná tíðari landmælinga uppfærslur en er mögulegt með hefðbundnu tækni svo sem sjávarfallamælitæki og þyngdaraflstæki, sem er notað til að mæla þyngdaraflssviðið. Til þess að hjálpa mælingar og viðhalda réttu hitastigi umhverfis atóma, fínstilltu tveir menn frá NIST að nafni Wes Tew og Greg Strouse tvö hitamælitæki úr platínu, en þessi mælitæki voru sett í lofttóm hólf í klukkunni í Colorado. Vísindamenn byggðu einnig geilsunarskjöld sem umkringir hólf atómsins, sem leyfir klukkunni að virka við stofuhita í staðinn fyrir hitastig undir -150°C.
Hægt er að lesa meira um þetta á http://www.sciencedaily.com/releases/2015/04/150421132031.htm
It was bit tricky translating it from English to Icelandic. Not because there were a lot of words but the vocabulary was extremely complicated. Words like lattice, gravitational shift and relativistic geodesy is something you don't hear every day and it was hard to figure out what those words meant. I used Google to figure out what the meaning of those words in English was and tried to find the perfect Icelandic word that described it. One time I couldn't find any word to describe it so instead of using a single word, I wrote the description of it instead to show the reader that it does mean that. Other than that, it wasn't that particulary tough to deal with.