Preliminary Study on the Effect of Heated Surfaces Upon Bloodstain Pattern Analysis

Abstract

Bloodstain pattern analysis (BPA) involves the interpretation of distinct blood patterns found at crime scenes following a violent act. In this paper, we explored for the first time the effects of surface temperatures upon blood impacting a horizontal surface (steel) with its implications in BPA explored. Specific surface temperatures were explored over the range 24-250°C which relate to the four major boiling regimes of liquid media; natural convection, nucleate boiling, transition boiling, and film boiling, where a series of blood drops tests were performed at varying impact velocities. Blood was found to separate into its components at temperatures of 50°C+, displayed as temperature induced blood rings, where a single secondary and a series of further inner rings are exhibited. This consequently led to the development of a new constant Cd heated expressing the decrease in spread factor (D(s)/D(o)) at the secondary ring.

Animal blood in translational research: How to adjust animal blood viscosity to the human standard

“…To warm up blood might not be always feasible, and eventually the performance of biomedical devices is examined under hypothermic conditions (Kirkpatrick et al, 2003). Blood stains during a crime can form at other temperatures than found in a body (Larkin & Banks, 2013). We therefore included testing the temperature profile of WBV and found that horse WBV showed the highest temperature dependency, followed by pig and human/sheep.…”

Alginate/xanthan gum hydrogels as forensic blood substitutes for bloodstain formation and analysis

“…21 Ideally, MP concentration would be representative of the PCV% of human blood, which typically ranges from 40-50%. [6][7][8]10,32,[54][55][56] Our cellular components only account for 9.5% v/v of the total material, largely due to the size of MPs used (approximately 22 mm) compared to the typical RBC size. Interestingly, the morphology of some of the MPs when visualized with SEM appears to have biconcave shapes and sizes similar to RBCs (Fig.…”

Degrees of contrast: Detection of latent bloodstains on fabric using an alternate light source (ALS) and the effects of washing

“…Once blood was drawn, it was immediately removed from a preservative-free vacutainer via 1 ml glass dropper, and two drops of blood were dropped on one side of the fabric piece to mimic blood temperature coming out of the body [12]. This was done because there is an inverse relationship between temperature and viscosity [13,14], and a change in viscosity due to temperature could affect how the blood interacts with the fabric. To ensure one side remained bloodless, a piece of cardboard was placed at the middle marker as a barrier.…”