This is a critical essay of 2000 words excluding references. you can go over the word limit by 200 words only . everything is explained in the assessment sheet attached….
Direct STR typing from fired and unfired bullet casings
From your own background, select a published article and define the following:
1- the methodology used in the article.
2- The type of data.
3- The method of analysis
Article title: Direct STR typing from fired and unfired bullet casings
- The methodology used in the article
Experimental research aimed at studying: the effect of firing bullets on DNA deposited on bullet casings; the effect of gun and ammunition types on short tandem repeat (STR) profile quality; and the feasibility of using direct PCR in real-world cases via typing of mock casework samples.
- Type of data
Numerical, measurable, and testable data (STR profiles)
- The method of analysis
- Raw data were analyzed using GeneMapper1 ID v 3.2.1.
- Relevant data were exported to the open-source statistical program R.
- Four factors were investigated: the effect of DNA extraction on the amount of DNA recovered; the effect of firing on DNA loss; the effect of gun type and ammunition type; and the number of donor alleles and non-donor alleles observed.
- All statistical comparisons were carried out using Bayesian credible intervals. Bayesian 95% credible intervals of the means and 95% credible intervals for effect sizes were calculated using “Bayesian Estimation Supersedes the T-test (BEST)”
The research was approved by the Ethical Committee, Faculty of Medicine, Prince of Songkla University (approval no. 57-027-19-2).
Thanakiatkrai, P., & Rerkamnuaychoke, B. (2019). Direct STR typing from fired and unfired bullet casings. Forensic science international, 301, 182-189.