46 research outputs found

    The impact of evidence lineups on fingerprint expert decisions

    Get PDF
    Forensic examiners routinely compare a crime‐relevant mark of unknown origin against a single suspect's sample, which may create an expectation that the two will match. We tested how embedding the suspect's sample among known‐innocent fillers (i.e., an evidence lineup ) affects expert decision‐making. Experienced fingerprint examiners (N = 43) compared crime‐relevant marks against either individual suspect fingerprints (i.e., the standard procedure) or arrays of fingerprints (i.e., evidence lineups), with a matching fingerprint either present or absent. Evidence lineups promoted conservative decision‐making, as evidenced by fewer correct IDs and a higher rate of inconclusive judgments. Though errors were rare, evidence lineups also occasionally revealed errors that would have otherwise gone undetected. Our findings thus support arguments that evidence lineups can expose fraud, identify flawed methodologies, and curb overconfidence. The potential benefits and challenges of implementing evidence lineups in forensic laboratories are discussed

    The low prevalence effect in fingerprint comparison amongst forensic science trainees and novices

    Get PDF
    The low prevalence effect is a phenomenon whereby target prevalence affects performance in visual search (e.g., baggage screening) and comparison (e.g., fingerprint examination) tasks, such that people more often fail to detect infrequent target stimuli. For example, when exposed to higher base-rates of ‘matching’ (i.e., from the same person) than ‘non-matching’ (i.e., from different people) fingerprint pairs, people more often misjudge ‘non-matching’ pairs as ‘matches’–an error that can falsely implicate an innocent person for a crime they did not commit. In this paper, we investigated whether forensic science training may mitigate the low prevalence effect in fingerprint comparison. Forensic science trainees (n = 111) and untrained novices (n = 114) judged 100 fingerprint pairs as ‘matches’ or ‘non-matches’ where the matching pair occurrence was either high (90%) or equal (50%). Some participants were also asked to use a novel feature-comparison strategy as a potential attenuation technique for the low prevalence effect. Regardless of strategy, both trainees and novices were susceptible to the effect, such that they more often misjudged non-matching pairs as matches when non-matches were rare. These results support the robust nature of the low prevalence effect in visual comparison and have important applied implications for forensic decision-making in the criminal justice system

    Perioperative echocardiography-guided hemodynamic therapy in high-risk patients:a practical expert approach of hemodynamically focused echocardiography

    Get PDF
    The number of high-risk patients undergoing surgery is growing. To maintain adequate hemodynamic functioning as well as oxygen delivery to the vital organs (DO2) amongst this patient population, a rapid assessment of cardiac functioning is essential for the anesthesiologist. Pinpointing any underlying cardiovascular pathophysiology can be decisive to guide interventions in the intraoperative setting. Various techniques are available to monitor the hemodynamic status of the patient, however due to intrinsic limitations, many of these methods may not be able to directly identify the underlying cause of cardiovascular impairment. Hemodynamic focused echocardiography, as a rapid diagnostic method, offers an excellent opportunity to examine signs of filling impairment, cardiac preload, myocardial contractility and the function of the heart valves. We thus propose a 6-step-echocardiographic approach to assess high-risk patients in order to improve and maintain perioperative DO2. The summary of all echocardiographic based findings allows a differentiated assessment of the patient's cardiovascular function and can thus help guide a (patho)physiological-orientated and individualized hemodynamic therapy

    Three years of atmospheric concentrations of nitrated and oxygenated polycyclic aromatic hydrocarbons and oxygen heterocycles at a central European background site

    No full text
    Nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs, OPAHs) are abundant in the atmosphere and contribute significantly to the health risk associated with inhalation of polluted air. Despite the health hazard they pose, NPAHs and OPAHs were rarely included in monitoring. The aim of this study is to provide the first multi-year temporal trends of the concentrations, composition pattern and fate of NPAHs and OPAHs in air from a site representative of background air quality conditions in central Europe. Samples were collected every second week at a rural background site in the Czech Republic during 2015–2017. Concentrations ranged from 1.3 to 160 pg m−3 for ÎŁ17NPAHs, from 32 to 2600 pg m−3 for ÎŁ10OPAHs and from 5.1 to 4300 pg m−3 for ÎŁ2O-heterocycles. The average particulate mass fraction (Ξ) ranged from 0.01 ± 0.02 (2-nitronaphthalene) to 0.83 ± 0.22 (1-nitropyrene) for individual NPAHs and from <0.01 ± 0.01 (dibenzofuran) to 0.96 ± 0.08 (6H-benzo (c,d)pyren-6-one) for individual OPAHs and O-heterocycles. The multiyear variations showed downward trends for a number of targeted compounds. This suggests that on-going emission reductions of PAHs are effective also for co-emitted NPAHs and OPAHs

    The impact of evidence lineups on fingerprint expert decisions

    No full text
    Forensic examiners routinely compare a crime‐relevant mark of unknown origin against a single suspect's sample, which may create an expectation that the two will match. We tested how embedding the suspect's sample among known‐innocent fillers (i.e., an evidence lineup ) affects expert decision‐making. Experienced fingerprint examiners (N = 43) compared crime‐relevant marks against either individual suspect fingerprints (i.e., the standard procedure) or arrays of fingerprints (i.e., evidence lineups), with a matching fingerprint either present or absent. Evidence lineups promoted conservative decision‐making, as evidenced by fewer correct IDs and a higher rate of inconclusive judgments. Though errors were rare, evidence lineups also occasionally revealed errors that would have otherwise gone undetected. Our findings thus support arguments that evidence lineups can expose fraud, identify flawed methodologies, and curb overconfidence. The potential benefits and challenges of implementing evidence lineups in forensic laboratories are discussed

    Fast Formation of Nitro-PAHs in the Marine Atmosphere Constrained in a Regional-Scale Lagrangian Field Experiment

    No full text
    Polycyclic aromatic hydrocarbons (PAHs) and some of their nitrated derivatives, NPAHs, are seemingly ubiquitous in the atmospheric environment. Atmospheric lifetimes may nevertheless vary within a wide range, and be as short as a few hours. The sources and sinks of NPAH in the atmosphere are not well understood. With a Lagrangian field experiment and modeling, we studied the conversion of the semivolatile PAHs fluoranthene and pyrene into the 2-nitro derivatives 2-nitrofluoranthene and 2-nitropyrene in a cloud-free marine atmosphere on the time scale of hours to 1 day between a coastal and an island site. Chemistry and transport during several episodes was simulated by a Lagrangian box model i.e., a box model coupled to a Lagrangian particle dispersion model, FLEXPART-WRF. It is found that the chemical kinetic data do capture photochemical degradation of the 4-ring PAHs under ambient conditions on the time scale of hours to 1 day, while the production of the corresponding NPAH, which sustained 2-nitrofluoranthene/fluoranthene and 2-nitropyrene/pyrene yields of (3.7 ± 0.2) and (1.5 ± 0.1)%, respectively, is by far underestimated. Predicted levels of NPAH come close to observed ones, when kinetic data describing the reactivity of the OH-adduct were explored by means of theoretically based estimates. Predictions are also underestimated by 1–2 orders of magnitude, when NPAH/PAH yields reported from laboratory experiments conducted under high NOx conditions are adopted for the simulations. It is concluded that NPAH sources effective under low NOx conditions, are largely underestimated
    corecore