Pre-validation of a MALDI MS proteomics-based method for the reliable detection of blood and blood provenance.

The reliable identification of blood, as well as the determination of its origin (human or animal) is of great importance in a forensic investigation. Whilst presumptive tests are rapid and deployed in situ, their very nature requires confirmatory tests to be performed remotely. However, only serological tests can determine blood provenance.

Investigation of infinite focus microscopy for the determination of the association of blood with fingermarks.

The determination of the type of deposition mechanism of blood within fingermarks at the scene of violent crimes is of great importance for the reconstruction of the bloodshed dynamics. However, to date, evaluation still relies on the subjective visual examination of experts. Practitioners encounter three types of scenarios in which blood may be found in fingermarks and they refer to the following three deposition mechanisms: (i) blood marks, originating from a bloodied fingertip; (ii) marks in blood, originating from a clean fingertip contacting a blood contaminated surface; (iii) coincidental deposition mechanisms, originating from a clean fingertip contacting a clean surface, leaving a latent fingermark, and subsequent contamination with blood.

"Cannot Decide": The Fine Line Between Appropriate Inconclusive Determinations Versus Unjustifiably Deciding Not To Decide.

Inconclusive decisions, deciding not to decide, are decisions. We present a cognitive model which takes into account that decisions are an outcome of interactions and intersections between the actual data and human cognition. Using this model it is suggested under which circumstances inconclusive decisions are justified and even warranted (reflecting proper caution and meta-cognitive abilities in recognizing limited abilities), and, conversely, under what circumstances inconclusive decisions are unjustifiable and should not be permitted.

Accuracy and reliability of feature selection by Chinese fingerprint examiners.

The selection of minutiae is a critical part of the analysis phase within the fingerprint identification methodology, known as analysis-comparison-evaluation-verification. This study assessed the accuracy and reliability of the minutiae selections of 92 Chinese fingerprint examiners during the analysis phase, absent an exemplar print, of the fingerprint identification process. Specifically, we measured the accuracy (trueness) of their annotation of minutiae, and we measured their reliability which is the reproducibility and repeatability in their annotations in one complex mark by using R software.

A proteomic approach for the rapid, multi-informative and reliable identification of blood.

Blood evidence is frequently encountered at the scene of violent crimes and can provide valuable intelligence in the forensic investigation of serious offences. Because many of the current enhancement methods used by crime scene investigators are presumptive, the visualisation of blood is not always reliable nor does it bear additional information. In the work presented here, two methods employing a shotgun bottom up proteomic approach for the detection of blood are reported; the developed protocols employ both an in solution digestion method and a recently proposed procedure involving immobilization of trypsin on hydrophobin Vmh2 coated MALDI sample plate.