Holistic facial composite creation and subsequent video line-up eyewitness identification paradigm

The paradigm detailed in this manuscript describes an applied experimental method based on real police investigations during which an eyewitness or victim to a crime may create from memory a holistic facial composite of the culprit with the assistance of a police operator. The aim is that the composite is recognized by someone who believes that they know the culprit. For this paradigm, participants view a culprit actor on video and following a delay, participant-witnesses construct a holistic system facial composite. Controls do not construct a composite. From a series of arrays of computer-generated, but realistic faces, the holistic system construction method primarily requires participant-witnesses to select the facial images most closely meeting their memory of the culprit. Variation between faces in successive arrays is reduced until ideally the final image possesses a close likeness to the culprit. Participant-witness directed tools can also alter facial features, configurations between features and holistic properties (e.g., age, distinctiveness, skin tone), all within a whole face context. The procedure is designed to closely match the holistic manner by which humans’ process faces. On completion, based on their memory of the culprit, ratings of composite-culprit similarity are collected from the participant-witnesses. Similar ratings are collected from culprit-acquaintance assessors, as a marker of composite recognition likelihood. Following a further delay, all participants — including the controls — attempt to identify the culprit in either a culprit-present or culprit-absent video line-up, to replicate circumstances in which the police have located the correct culprit, or an innocent suspect. Data of control and participant-witness line-up outcomes are presented, demonstrating the positive influence of holistic composite construction on identification accuracy. Correlational analyses are conducted to measure the relationship between assessor and participant-witness composite-culprit similarity ratings, delay, identification accuracy, and confidence to examine which factors influence video line-up outcomes

Individual differences in upright and inverted face recognition, simultaneous face matching and object recognition ability throughout the adult lifespan

Objectives: Superior face recognition ability is important for policing and other security roles, and selection of suitable staff for certain operations is essential. Age may be a factor. Our research aims were to enhance theoretical understanding of the relationship between different visual processing tasks, as well as to examine whether the normal mid-thirties peak in face recognition ability would transfer to alternative forensically-relevant face processing tests. Design: Correlational designs examined the relationships between upright and inverted face recognition, simultaneous face matching, object recognition and age in Experiment 1; and face matching CCTV images, passport images and age in Experiment 2. Methods: Worldwide media articles led to participants (n = 250,000) completing a ‘could you be a super-recogniser?’ teaser-test, and in Experiment 1, teaser-test high performers (n = 20,000+; 18-76 years-old) were recruited. In Experiment 2, participants (n = 5,000+) included Metropolitan Police ‘super-recognisers’. Results: Performances across all tests correlated. Face recognition ability peaked at approximately 34-years; face matching high-quality images at 36. Performance subsequently declined. In contrast, the face inversion effect positively correlated with age, while object recognition ability remained consistent throughout the lifespan. No reliable peak age was found for CCTV and passport image matching. Conclusions: The optimum age for high performance (including police officers) on forensic facial examination and recognition tasks appears to be the mid-thirties. Regardless of age, some exceptional participants made few errors on any task, and discussion will focus on these individuals, as well as how high performers in the police positively impact investigations

The wisdom of the crowd: a case of post- to ante-mortem face matching by police super-recognisers

This case report describes novel methodology used to identify a 43-year-old post-mortem photo of a drowned male recovered from a London river in the 1970’s. Embedded in an array of foils, police super-recognisers (n = 25) possessing superior simultaneous face matching ability, and police controls (n = 139) provided confidence ratings as to the similarity of the post-mortem photo to an ante-mortem photo of a man who went missing at about the same time Indicative of a match, compared to controls, super-recognisers provided higher ratings to the target than the foils. Effects were enhanced when drawing on the combined wisdom of super-recogniser crowds, but not control crowds. These findings supported additional case evidence allowing the coroner to rule that the deceased male and missing male were likely one and the same person. A description of how similar super-recogniser wisdom of the crowd procedures could be applied to other visual image identification cases when no other method is feasible is provided

17O NMR: A "Rare and Sensitive" Probe of Molecular Interactions and Dynamics

This review summarizes recent developments in the area of liquid-state Nuclear Magnetic Resonance spectroscopy of the 17O nucleus. It is structured in Sections, respectively covering (a) general background information, with special emphasis on spin relaxation phenomena for quadrupolar nuclei and in paramagnetic environments, (b) methods for the calculation of 17O NMR parameters, with illustrative results, (c) applications in chemistry and materials science, (d) application to biomolecules and biological systems, (e) relaxation phenomena, including contrast agents for Magnetic Resonance Imaging (MRI). The 17O nucleus emerges as a very sensitive probe of the local environment ─ including both bonding and non-bonding interactions ─ and molecular motions

Untersuchungen zu Struktur, Dynamik und Solvensinteraktion von Übergangsmetall-Aminopolycarboxylat Komplexen in Lösung

Die vorliegende Arbeit befasst sich mit Untersuchungen zur Reaktivität einer Serie von Übergangsmetall-Komplexen, mit dem Chelat-Liganden EDTA und Variationen dieses Strukturmotivs. Um die Auswirkung der Chelatisierung auf die Wasseraustauchkinetik zu bewerten, wurden zunächst Lösungsstruktur, Austauschgeschwindigkeit und der zugrunde liegende Austauschmechanismus für den Komplex [FeII(EDTA)(H2O)]2- aufgeklärt, der überaus große Bedeutung in der Koordinationschemie, sowie industriellen und medizinischen Anwendungen besitzt (Kapitel 2). Sterisch anspruchsvolle Chelat-Liganden führen zu einer beträchtlichen Abschirmung des Zentralatoms, wobei das Ausmaß entscheidend durch die Ligandstruktur beeinflusst wird. Im Rahmen dieser Arbeit wird der Einfluss eines strukturell veränderten EDTA Ligandmotivs auf die Wasseraustauschreaktion einer Serie von Übergangsmetall-Komplexen untersucht. Ein klarer Zusammenhang zwischen sterischer Hinderung und dem zugrunde liegenden Austauschmechanismus konnte für alle untersuchten Metallkomplexe beobachtet werden (Kapitel 3). In wässriger Lösung zeigen Aminopolycarboxylat-Komplexe häufig Liganddynamik. Durch strukturelle Modifikationen der -NCH2CH2N- Brücke kann eine vollständige Unterdrückung dieses dynamischen Prozesses erzwungen werden. Die gewonnenen Erkenntnisse zu Lösungsstruktur, Wasseraustauschkinetik und mechanismus erlauben die Bewertung des Einflussfaktors eines statischen Ligandsystems auf die Reaktivität des Komplexes im Vergleich zu strukturanalogen Systemen mit flexiblem Ligandgerüst (Kapitel 4). Auf der Basis der gesammelten kinetischen und mechanistischen Erkenntnisse konnte die Substitutionsreaktion des labilisierten Lösungsmittelmoleküls gegen einen entsprechenden monodentaten Liganden (Fluorid) vorhergesagt werden. Der ternäre Fluoridkomplex zeichnet sich durch eine deutlich geringere Reaktivität gegenüber molekularem Sauerstoff aus. Der Ersatz des labilen Wassermoleküls stellt somit eine wirksame Möglichkeit dar, die Autooxidation des [FeII(EDTA)(H2O)]2- Komplexes zu hemmen (Kapitel 5).In order to evaluate the impact of the ligand architecture on the water exchange kinetics, we investigated the solution structure, the exchange kinetics and the exchange mechanism of the [FeII(EDTA)(H2O)]2- complex, a compound of high relevance in coordination chemistry, industrial and medical applications (see Chapter 2). Steric constraints around the metal centers lead to a considerable shielding of the metal center, which in turn can be triggered by ligand design. We studied the influence of the structurally modified EDTA ligand motif on the water exchange reaction of several transition metal complexes and found a clear relationship between increased steric crowding through tailored ligand design and the observed exchange mechanism (Chapter 3). In aqueous solution, chelates are often found to undergo dynamic rearrangements. Rigidity of the coordination cages can be enforced by placing steric constraints in the ligand architecture. The studied solution details (structure, kinetics and mechanism) of complexes with impeded ligand rearrangement in aqueous media allow us to draw conclusions on the influence of a flexible coordination cage on complex reactivity (Chapter 4). The kinetic and mechanistic understanding of the FeII-EDTA system, led us predict a feasible exchange of the labile water molecule for other mono-dentate ligands, which we demonstrated for the fluoride ligand. The significantly lowered lability, makes this mixed ligand complex interesting in hindering unwanted oxidative degradation (Chapter 5)