Few more pictures are in my flickr stream.

Looking up the sky – a week ago my wife announced that she saw a meteor. Since we were both semi-awake at the time and I must say that probably I glimpsed at it with the corner of my eye, nodded and went to sleep. Not much to do about it … or so I thought.

As it happens we saw one of the Orionids. This is another annual meteor shower, similar to Perseids which were described in this article. As other meteor showers they are named after their radiant, which is located near constellation Orion. Usually they last from 15-29 of October with the maximum between 20-22 of October and this year the peak will be seen on the 21 of October. On average the produce from 20-25 meteors per hour. But reports are claiming that this years activity could be similar to last years, which was around 60 meteors per hour. If you were to be looking for it the radiant is about 10 degrees north of Betelgeuse in the southeastern sky.

First observations of the Orionids were made by E.C. Herrick in the 1839-1840. First documented record was which produced accurate forecasts for the next year were made by the A.S. Herschel. It is now known that the Orionids are a by product of the well-known Halley’s Comet.

Happy hunting.

Are you sure you know what you eat and drink? Think for a while! Plastics is really everywhere – in cosmetic packaging, drinking bottles, food containers, children toys, credit cards, clothing, … It seems as we can not live without it anymore.

Plastics is organic material made synthetically or semi-synthetically. It is a polymer comprised from molecules of high molecular weight. It’s hard, soft, colored, clear and it can even smell nice (perfumed). Different chemicals enable such features and/or reduce the cost of production. Some of these chemicals are very dangerous. Therefore every plastic piece should be labeled.  Are you interested in learning how to distinguish between different plastics? Read on.

Plastics logo is represented by triangle of three arrows and a number or acronym in the middle. Numbers and acronyms will tell you what type of plastic the product was made of. Numbers 2 (HDPE), 4 (LDPE) and 5 (PP) pose no harm to your health. Plastics with numbers 1 (PETE, PET), 3 (PVC, V), 6 (PS) and 7 (other, O) contain chemicals, which present a danger to your health, especially to young children and fetuses, that are yet developing. Exceptionally hazardous is bis-phenol-A (BPA), that belongs to the group 7. Chemicals will diffuse from the plastic to the liquids or food when warmed or heated. Even using plastic material in a microwave or a dishwasher signifies a danger of diffusing chemicals into food chain. Chemical substances mimic reproductive hormone estrogen and cause  reproductive developmental issues, as well as obesity, prostate cancer, breast cancer and attention-deficit disorder, to name a few,.

There is not enough research done to firmly support such negative influences of chemical substances. Most of them were done on animals, although first reports from human blood and urine samples support animal studies. These are long-term studies and take some time to link all the factors that influence our health. Two months ago BPA was found in a glass jarred baby food. Perhaps the environment is already contaminated with chemicals.

There is another drawback that needs to be considered. Plastic is hardly degradable and poses a great risk for the environment and animals. Just think how many animals die because they suffocate from plastic bags or eat small plastic pieces. Fortunately, there is an alternative in the production – biodegradable bags and containers. This is a very promising solution, but so far it is too expensive and a long-term storage of food and liquids in such biodegradable containers is not a very good choice as leakage compromises their convenience.

Many countries and manufacturers are already aware of the danger that plastic represents. BPA is banned in most of them, but not other chemicals. Although we hardly influence government choices, we still have a choice of what to buy and we can always try to recycle instead simply throwing away.

Related articles by Zemanta

• BPA, chemical used to make plastics, found to leach from polycarbonate drinking bottles into humans (scienceblog.com)
• Bioplastics Industry Getting a Second Wind (scienceblog.com)
• BPA-Spiked Urine: New Study Points to Polycarbonate Bottles (treehugger.com)

Image by Beige Alert via Flickr

Recently I daily enjoyed watching CSI series on our local TV station. I am not into forensic science but I work in a lab for molecular biology and I know a thing or two about DNA sequencing. I would like to show you my perspective of the sequencing process that is simplified by the CSI series.

In school we learn about genetic material. In brief: chromosomes are composed of genes, genes are constituted of DNA and DNA is arranged in a long sequence of four different nucleotides: adenosine (A), thymine (T), guanine (G) and cytosine (C). The sequence of millions of this four nucleotide letters represents our genome. And here the real work begins. Read further if you are interested in how to obtain a sequence of particular gene, for example to determine the relationship between two persons.

First of all, forensics gather material and bring it to the lab: a hair with a root, some cells under nails, a piece of skin from scratch or a sample of blood. Such material contains cells with genetic material. Lab technician extracts genetic material from cells: more cells mean more genetic material and this leads to more accurate results. After acquiring genetic material appropriate gene or genes are amplified (augmented in quantity). After amplification, a so called PCR product is cleaned from salts and other unused reagents. The next step is amplifying the product in the way that four different dyes are incorporated: each nucleotide letter is represented with different color. Incorporated dye stops the amplification and various lengths of fragments are obtained. In a machine called sequencer fragments move through a special medium with the help of electric current. A laser detects colored fragments and camera records the sequence of detected dyes a.k.a. nucleotides. The result is a chromatogram with four colored curves representing a nucleotide sequence of specific gene.

Image via Wikipedia

A lot of work is implicated to get printed result from a fresh specimen. Such labs occupy specially trained personnel and special lab equipment distribution: a separate room for extracting genetic material, room for amplification, for detection and the last one for sequencing. Trained personnel and separate rooms are needed to avoid any possible contamination of starting specimen or any of the subsequent steps.

However, apart from CSI series lab technician in real-life forensic science works only in a lab. He does not operate with criminals and does not wear a gun. Criminal acts are quickly solved only in TV series. In reality investigation proceeds  much slower.

Related articles by Zemanta

• Sequencing a Human Genome In a Week (science.slashdot.org)
• Glossary For Biotechnology (slideshare.net)
• Personal genomics – could “Gattaca” come true? (twm-kd.com)

Cover of Gattaca

A few weeks ago I watched an interesting movie with Uma Thurman and Ethan Hawk, Gattaca (1997), which raised my attention. It’s about genetically inferior man with a strong wish to fly to planet Saturn. Because of his ”bad” genes and short life expectancy he can not fulfill his wish. A genetically superior man, but paraplegic, helps him to realize his wish. He lends him his generic ID. How do they manage not to get caught?

Genome is something you are born with. It’s unique (except with identical twins), it’s your ID, you can not change it. It’s everywhere on you: hair, eyelashes, saliva,… One hair with a root is enough to determine your genome sequence or sequence of a certain gene (everyone has probably watched one of those many criminal series). Many commercial services are already available to determine DNA sequence. Why do we even need our genome to be determined? First of all, it is being used in a forensics, as we already know. But lately it is getting more and more popular in a predictive and personalized medicine. What are they?

Image via Wikipedia

In personalized medicine genome/gene information is being used to determine the most suitable drug to be applied to a patient. In this case it is meant in appropriate amount and appropriate way in order to increase drug efficacy, and with as less side effects as possible. But there are only a few examples so far. It is being expected this kind of drug administration to emerge rapidly.

Another aspect of handling of gene information is in predictive medicine. It is useful for disease risk prediction based on genetic markers. A small change (mutation) in a gene sequence might cause a disease. You should be aware that not every mutation in a gene information also means a risk for a disease. For someone to develope a certain disease there are genetic and environmental factors involved. And both are not yet fully understood. The goal of predicting the future disease is that the health care proffesionals and patients themselves are active in lifestyle modification and increased physician surveillance.

The benefit of personal genomics has already been proven in a breast cancer and some other diseases too. But overall, the usefullnes of genome information in today’s medicine is currently limited.

After I saw this movie I asked myself; what about the ethics of  sharing personal genome information? What about discrimination? From an insurer or an employer. Fortunately, in some countries there are laws already that regulate this topic. Let’s hope that future from the movie will not come true. We still want our destiny to be in our hands, don’t we?

Related articles by Zemanta

• Gene Environment Interactions2 (slideshare.net)
• Get Your DNA Sequenced for $200K Less! (blisstree.com)
• Personal Genome Project – Personalized Medicine and Maybe Food Too? (ducknetweb.blogspot.com)
• What do genetic testing and real estate have in common? (scienceblog.com)
• Scientists identify gene that predicts post-surgical survival from brain metastasis of breast cancer patients (scienceblog.com
• Chasing the Genetic Ghosts of Mental Illness (psychcentral.com)
• Genomics and Personalized Medicine: Facts, Fiction,Future? (http://www.genomicslawreport.com)
• The Genomic Frontier: Personalized Medicine in Action (http://venturebeat.com)

“Perseids” parent body is a comet Swift-Tuttle; which was discovered in 1862 by Lewis Swift and Horace Parnell Tuttle.  Comet made a return trip back in 1992. Perseids meteor shower has been observed for about 2000 years, maybe more.  Earliest records can be seen in eastern journal and annals which date back to 36 AD. But Catholics referred to it as “tears of St. Lawrence”, since meteors seemed to be in abundance during the festival of that saint. This particular meteor shower was discovered by Adolphe Quételet, who made his report of meteor shower emanating from the constellation of Perseus in 1835.

Observers on the Northern Hemisphere can start seeing Perseid meteors as early as 23 of July, when one meteor per hour can be visible. During the course of three weeks this rate slowly builds-up. At peak; which is usually around August 12-13 we can spot 50-80 meteors per hour. They rapidly decline to about 10 per hour by the August 15 and can rarely be seen after the 22 of August. They emanate from constellation of Perseus. It is good to wait for the constellation to rise up on the sky and observe topically fast and bright meteors.

If you are on vacation or have time and there is not a cloud in the sky at night take a load of and catch a falling star.

Few days ago project SETI@home celebrated its 10th anniversary. I can’t believe that it has been so long. We were recording signals from outer space for a bit longer time, but past ten years some of those signals have been properly analyzed and listened to. Looking for aliens extra terrestrial life, great, lovely and fascinating. I guess. Let’s take a look at what SETI@home accomplished in ten years. But first, we have too get a little more knowledge about how SETI@home works.

Arecibo Observatory is always listening to that part of the sky where it is located and while it’s operating data is being recorded. This data has to be split in smaller units which are then analyzed by SETI@home clients. Telescope records a certain number of workunit groups on each day. Those groups are then split into 256 units by frequency. Each unit is 107 seconds long and units time overlaps for about 20 seconds. Workunit database wasn’t updated for some time now, but on August 2008 there were 1840943 workunit groups recorded and made available to SETI@home clients all over the world.

When client is activated it connects to SETI server, downloads a workunit and starts analyzing it. When analysis is complete it sends results back to SETI server and downloads another package. And so on and so on. Well, Arecibo telescope wasn’t available all the time to SETI group and over the years they’ve been getting less and less data to analyze and data was recorded only for 1446 days (on August 2008). SETI@home has also become a platform for some other studies that rely on computing power.

Over past ten years SETI2home had over 5 million clients all of them aggregated for more than 2 million years of computing time. Currently with more than 300.000 computers in the network SETI@home can compute at 528 TFLOPS beating IBM‘s Blue Gene sustained performance at 478 TFLOPS.

Congratulations to SETI@home project, they proved that distributed computing on a large scale actually works and this was the biggest computational task in human history. Until now they performed more than 10²¹ floating point operations. But the biggest achievement by far is a number of people out there that have the same screen saver for the past ten years.

That is an astonishing accomplishment!

Related articles by Zemanta

• UFOs – Do You Believe? (lockergnome.com)
• Alien Census: Can We Estimate How Much Life Is Out There? (sciam.com)
• Because Faith Trumps Science: (brothersjuddblog.com)
• Life on other planets? You bet, says SETI pioneer (seattlepi.com)
• First (human) tweet from Outer Space! (thenextweb.com)