Saturday, August 27, 2011
Friday, May 27, 2011
Coating Clears Up Fingerprints
Over the past few months scientists at Penn State University have been working on developing a coat that would clear up fingerprints. Sometimes scientists are not always able to retrieve fingerprints from certain objects. A group of scientists at Penn State have recently developed a “conformal coating process” that can reveal hard-to-develop fingerprints on nonporous surfaces without altering the chemistry of the print. Scientists Shaler and Ahklesh Lakhtakia, Charles Godfrey Binder “used a form of physical vapor deposition a method that uses a vacuum and allows vaporized materials to condense on a surface creating a thin film” This new process is very beneficial because it gives forensics scientists the ability to collect fingerprints from fragments of incendiary or explosive devices and still be able to analyze the chemicals that were used in the device. The coating material is heated in a vacuum, while the artifact to be coated is rotated fairly quickly to allow deposition over the entire surface. This process is very quick and efficient. It takes 15 minutes to produce the coating. These scientists are currently trying to develop “a portable device that could be brought to a crime scene and produce readable fingerprints on site.”
This article is very important to society because it gives forensics scientists the ability to identify and collect fingerprints that they wouldn’t be able to do before. This process should be used because it will make the process of collecting hard to obtain fingerprint samples much easier.
I chose this article because I was unaware of this new method. I was very interested in the advances forensic scientists have made in their field. This new method could be greatly beneficial for the law enforcement. I thought this article was pretty well written, but I thought it could have included more details regarding the topic.
White, James. "Coating Clears Up Fingerprints." Forensic Magazine. Web. 22 May 2011. <http://www.forensicmag.com/news/coating-clears-fingerprints>.
Posted for R.Minetti
Wednesday, May 25, 2011
Forensic Student Displays Artistic Talent
To emphasize the need to develop our students' talents across the WHOLE curriculum, here are examples of our science students, who have also spent significant time pursuing and developing their artistic talent. In these hard economic times too often cuts are made in the arts. These works are strong evidence for educators and communities to insist on maintaining a full and meaningful curriculum!!
Kyrie chose for her AP Art portfolio to produce digital renderings of the story behind foxes in Japanese folklore. Currently, Kyrie is a student in the Forensics course. She has taken four years of science in Bronxville, the "Core", our half year Freshman and Sophomore science courses (Core Chemistry Honors, Core Physics Honors, Core Biology Honors and Core Earth Science), and Biology II Honors. Kyrie has also taken AP courses in AP English Literature.
Sunday, May 22, 2011
Forensic Scientists Improve DNA Analysis With Mummy-inspired Bone-baking
Original Text:
February 1, 2008 — Forensic scientists analyzing bones found in the Gobi desert discovered that the DNA within them could be surprisingly easily extracted. In an experiment designed to mimic the conditions that affected those bones, baking a particularly difficult sample made the DNA much more easily extracted, probably because it makes it easier to break open more cells and expose more of the DNA molecules. Mummies have always held secrets, but now one of them has led to a new DNA technique.
Our fascination with mummies has sold millions at the box office. Now these preserved people -- mummies more than 800 years old -- are helping scientists reveal the mysteries of the past.
University of New Haven forensic scientist Dr. Heather Coyle is experimenting with a new technique by going back in time.
These are skeletal remains recently gathered from a Gobi desert cave. Surprisingly, Dr. Coyle was able to extract DNA from these mummies, but when she tried the same method on a body found in the USA, she was not as successful. "We realized that the bone we were trying to process was not yielding DNA from the case we were working on," Dr. Coyle said.
Standard DNA procedure for bones is to freeze them. When Coyle and her team re-examined the mummy remains they realized the Gobi desert created a natural bone baking process.
"It makes the bone more brittle so it makes it easier to grind and break open more cells, so we think we are accessing more DNA to begin with," Dr. Coyle said. Dr. Coyle decided to mimic nature by baking the cold case bones for 72 hours. Liquid nitrogen was then poured into a pulverizer. The bone was placed inside, ready to be crushed. After a short cycle the bone was turned to powder and ready for DNA extraction.
Coyle hopes her new technique will someday help close the book on several cold case files.
Summary:
When I was in sixth grade, I learned about Egyptian mummies in history class. Six years later, I found this article about forensic scientists in Egypt and how they could easily extract DNA from mummies! Even though the mummies had been dead for thousands of years, their DNA was still present. This article made me curious. How does a person’s DNA last for thousands of years? I thought the DNA had decomposed long ago. Not only did I find this article interesting myself; my parents were also amazed when I told them about it. Lastly, I would like to point out that this article reminded me of the King Tut exhibit at my favorite museum.
However, this article could have been done better in two ways. First of all, I think the original text was too long. Second, I think the author’s writing style was a little too opinionated. This is a news article, not an editorial!
Lastly, I think this article should not only be used in schools, I also think people outside of school (friends, family, penpals, etc.) might find this as interesting as I did. Hope you liked my summary, and don’t forget to comment. That is all.
Source: http://www.sciencedaily.com/videos/2008/0201-baking_out_dna.htm
February 1, 2008 — Forensic scientists analyzing bones found in the Gobi desert discovered that the DNA within them could be surprisingly easily extracted. In an experiment designed to mimic the conditions that affected those bones, baking a particularly difficult sample made the DNA much more easily extracted, probably because it makes it easier to break open more cells and expose more of the DNA molecules. Mummies have always held secrets, but now one of them has led to a new DNA technique.
Our fascination with mummies has sold millions at the box office. Now these preserved people -- mummies more than 800 years old -- are helping scientists reveal the mysteries of the past.
University of New Haven forensic scientist Dr. Heather Coyle is experimenting with a new technique by going back in time.
These are skeletal remains recently gathered from a Gobi desert cave. Surprisingly, Dr. Coyle was able to extract DNA from these mummies, but when she tried the same method on a body found in the USA, she was not as successful. "We realized that the bone we were trying to process was not yielding DNA from the case we were working on," Dr. Coyle said.
Standard DNA procedure for bones is to freeze them. When Coyle and her team re-examined the mummy remains they realized the Gobi desert created a natural bone baking process.
"It makes the bone more brittle so it makes it easier to grind and break open more cells, so we think we are accessing more DNA to begin with," Dr. Coyle said. Dr. Coyle decided to mimic nature by baking the cold case bones for 72 hours. Liquid nitrogen was then poured into a pulverizer. The bone was placed inside, ready to be crushed. After a short cycle the bone was turned to powder and ready for DNA extraction.
Coyle hopes her new technique will someday help close the book on several cold case files.
Summary:
When I was in sixth grade, I learned about Egyptian mummies in history class. Six years later, I found this article about forensic scientists in Egypt and how they could easily extract DNA from mummies! Even though the mummies had been dead for thousands of years, their DNA was still present. This article made me curious. How does a person’s DNA last for thousands of years? I thought the DNA had decomposed long ago. Not only did I find this article interesting myself; my parents were also amazed when I told them about it. Lastly, I would like to point out that this article reminded me of the King Tut exhibit at my favorite museum.
However, this article could have been done better in two ways. First of all, I think the original text was too long. Second, I think the author’s writing style was a little too opinionated. This is a news article, not an editorial!
Lastly, I think this article should not only be used in schools, I also think people outside of school (friends, family, penpals, etc.) might find this as interesting as I did. Hope you liked my summary, and don’t forget to comment. That is all.
Source: http://www.sciencedaily.com/videos/2008/0201-baking_out_dna.htm
Wednesday, May 18, 2011
A study on the effect of storage duration and fabric type on DNA quantity extracted from dried seminal stains.
Sexual violence occurs in every culture, in all levels of society, and in every country of the world. In cases of sexual assault, especially in rape, examinations often involve searching items such as clothing and bedding for seminal stains.12 The seminal stains recovered on fabrics in the form of stained clothing, undergarments, and swabs on fabric material taken from the vagina and surrounding regions are submitted to DNA fingerprinting tests to compare them with the blood sample of the accused person. Isolation of DNA from such stains, particularly when the stains are old, is usually not possible. The causes could be degradation or decomposition of the biological material,which depends mainly upon the environmental conditions. Extraction was performed by using a genomic DNA purification kit (QIA amp DNA investigator kit for isolation of total genomic DNA from material stained with semen) on the first day as well as after 14 and 30 days. The results from the first day were used as reference samples. DNA quantity in dried seminal stains decreases with increased storage duration, and DNA recovery from natural fabrics (cotton and silk) is much higher than from artificial fabric (polyester), with the maximum yield from cotton followed by silk and polyester. Therefore, in the medicolegal practice, it is recommended that cotton fabric be used for swabs for collection of seminal stains.
This article affects all of humanity because rape is a serious problem around the whole world. With the help of DNA being extracted from clothing, many victims can be helped by the catching of the perpetrator.
The article was long and structured. It broke down everything that was needed to be known and was well written. All key points were addressed and everything was explained properly.
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