Amidoschwarz10B in der forensischen Spurenuntersuchung: Vergleichende Untersuchungen an forensischem Spurenmaterial

Zusammenfassung: Blutspuren gehören zu den aussagekräftigsten Spuren in der forensischen Fallanalyse. Einerseits kann die Beurteilung von Aussehen, Menge, Form und Verteilung an Tatorten Hinweise auf den Tathergang geben. Andererseits lassen sich heute auch aus kleinsten Blutmengen zumeist vollständige DNA-Profile erstellen, die dann ebenfalls eine Rekonstruktion des Tatablaufs und über die molekulargenetische DNA-Analyse Aussagen zur Tatbeteiligung von Personen ermöglichen. In der vorgestellten Studie wurden Vollblutproben auf unterschiedliche Spurenträger aufgebracht und mithilfe des Hexagon OBTI® auf das Vorhandensein von Blut hin untersucht. Nach Inkubation mit 2 verschiedenen Zubereitungen von Amidoschwarz10B konnte gezeigt werden, dass dessen Einsatz zu starken Beeinträchtigungen bzw. falsch-negativen Ergebnissen des OBTI führen kann. Ein negativer Einfluss von Amidoschwarz10B auf das Probenmaterial war hingegen bei den nachfolgend durchgeführten DNA-Analysen nicht festzustelle

Jets in deep-inelastic scattering at HERA

Jet cross sections in deep-inelastic scattering over a wide region of phase space have been measured at HERA. These cross section measurements provide a thorough test of the implementation of Quantum Chromodynamics in next-to-leading order (NLO) calculations. They also provide the opportunity to test the consistency of the gluon distribution in the proton as extracted from (mainly) inclusive DIS measurements. Comparison of the cross sections with NLO enables accurate extractions of the strong coupling constant, $\alpha_s$, to be made, several of which are reported here.Comment: Talk presented at "New Trends in HERA Physics", Ringberg Workshop, June 2001. 13pages, 12figure

On the Perturbative Stability of the QCD Predictions for the Ratio R=FL/FTR=F_L/F_T in Heavy-Quark Leptoproduction

We analyze the perturbative and parametric stability of the QCD predictions for the Callan-Gross ratio $R(x,Q^2)=F_L/F_T$ in heavy-quark leptoproduction. We consider the radiative corrections to the dominant photon-gluon fusion mechanism. In various kinematic regions, the following contributions are investigated: exact NLO results at low and moderate $Q^2\lesssim m^2$, asymptotic NLO predictions at high $Q^2\gg m^2$, and both NLO and NNLO soft-gluon (or threshold) corrections at large Bjorken $x$. Our analysis shows that large radiative corrections to the structure functions $F_T(x,Q^2)$ and $F_L(x,Q^2)$ cancel each other in their ratio $R(x,Q^2)$ with good accuracy. As a result, the NLO contributions to the Callan-Gross ratio are less than 10% in a wide region of the variables $x$ and $Q^2$. We provide compact LO predictions for $R(x,Q^2)$ in the case of low $x\ll 1$. A simple formula connecting the high-energy behavior of the Callan-Gross ratio and low-$x$ asymptotics of the gluon density is derived. It is shown that the obtained hadron-level predictions for $R(x\to 0,Q^2)$ are stable under the DGLAP evolution of the gluon distribution function. Our analytic results simplify the extraction of the structure functions $F_2^c(x,Q^2)$ and $F_2^b(x,Q^2)$ from measurements of the corresponding reduced cross sections, in particular at DESY HERA.Comment: 14 pages, 6 figures, revtex4; minor correction

DNA typing in wildlife crime : recent developments in species identification

Species identification has become a tool in the investigation of acts of alleged wildlife crimes. This review details the steps required in DNA testing in wildlife crime investigations and highlights recent developments where not only can individual species be identified within a mixture of species but multiple species can be identified simultaneously. ‘What species is this?’ is a question asked frequently in wildlife crime investigations. Depending on the material being examined, DNA analysis may offer the best opportunity to answer this question. Species testing requires the comparison of the DNA type from the unknown sample to DNA types on a database. The areas of DNA tested are on the mitochondria and include predominantly the cytochrome b gene and the cytochrome oxidase I gene. Standard analysis requires the sequencing of part of one of these genes and comparing the sequence to that held on a repository of DNA sequences such as the GenBank database. Much of the DNA sequence of either of these two genes is conserved with only parts being variable. A recent development is to target areas of those sequences that are specific to a species; this can increase the sensitivity of the test with no loss of specificity. The benefit of targeting species specific sequences is that within a mixture of two of more species, the individual species within the mixture can be identified. This identification would not be possible using standard sequencing. These new developments can lead to a greater number of samples being tested in alleged wildlife crimes