German Criminal Police Office

About: German Criminal Police Office is a government organization based out in Wiesbaden, Germany. It is known for research contribution in the topics: Population & Mass spectrometry. The organization has 254 authors who have published 338 publications receiving 8489 citations.

Modeling the Growth of Fingerprints Improves Matching for Adolescents

Abstract: We study the effect of growth on the fingerprints of adolescents, based on which we suggest a simple method to adjust for growth when trying to recover a juvenile's fingerprint in a database years later. Based on longitudinal data sets in juveniles' criminal records, we show that growth essentially leads to an isotropic rescaling, so that we can use the strong correlation between growth in stature and limbs to model the growth of fingerprints proportional to stature growth as documented in growth charts. The proposed rescaling leads to a 72% reduction of the distances between corresponding minutiae for the data set analyzed. These findings were corroborated by several verification tests. In an identification test on a database containing 3.25 million right index fingers at the Federal Criminal Police Office of Germany, the number of identification errors was reduced from 10 errors in 48 identification attempts to 1 in 48 by rescaling. The presented method is of striking simplicity and can easily be integrated into existing automated fingerprint identification systems.

Capillary electrophoresis‐laser induced fluorescence‐electrospray ionization‐mass spectrometry: A case study

Abstract: The simultaneous hyphenation of capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection and electrospray ionization-mass spectrometry (ESI-MS) as a novel combined detection system for CE is presented. β-Carbolines were chosen as model analytes with a forensic background. Nonaqueous CE as well as conventional CE with an aqueous buffer system are compared concerning efficiency and obtainable detection limits. The distance between the optical detection window and the sprayer tip was minimized by placing the optical cell directly in front of the electrospray interface. Similar separation efficiencies for both detection modes could thus be obtained. No significant peak-broadening induced by the MS interface was observed. The high fluorescence quantum yield and the high proton affinity of the model analytes investigated resulted in limits of detection in the fg (nmol/L) range for both detection methods. The analysis of confiscated ayahuasca samples and ethanolic plant extracts revealed complementary selectivities for LIF and MS detection. Thus, it is possible to improve peak identification of the solutes investigated by the use of these two detection principles.

The application of 3D-microprofilometry as a tool in the surface diagnosis of fossil and sub-fossil vertebrate hard tissue. An example from the Pliocene Upper Laetolil Beds, Tanzania

Abstract: Non-contact optical 3D-profiling instruments are often used in the study of surface modifications on fossil mammalian bone. The advantage of optical laser scanning for the study of fossil and sub-fossil bone is its non-contact nature, allowing the investigation of fragile and poorly preserved surfaces. The high resolution and fast measuring rate of this method make it an alternative to scanning electron microscopy (SEM) investigation if topography is to be visualized. This study analyses clusters of incisions in a suid humeral fragment from the Pliocene Upper Laetolil Beds. The marks show a characteristic crest structure that is also frequently found in mandible marks produced by the Australian termite species Mastotermes darwiniensis. The marks from the Laetolil Beds are, therefore, interpreted as also being caused by insect mandible action. An as yet unknown large insect species capable of modifying bone with their mandibles is thus postulated in the palaeohabitat represented by the hominid-bearing Upper Laetolil Beds. Copyright © 2001 John Wiley & Sons, Ltd.