200 research outputs found
Experiences of evidence presentation in court: an insight into the practice of crime scene examiners in England, Wales and Australia
Background: The ability to present complex forensic evidence in a courtroom in a manner that is fully comprehensible to all stakeholders remains problematic. Individual subjective interpretations may impede a collective and correct understanding of the complex environments and the evidence therein presented to them. This is not fully facilitated or assisted in any way with current non-technological evidence presentation methods such as poor resolution black and white photocopies or unidimensional photographs of complex 3D environments. Given the wide availability of relatively cheap technology, such as tablets, smartphones and laptops, there is evidence to suggest that individuals are already used to receiving visually complex information in relatively short periods of time such as is available in a court hearing. courtrooms could learn from this more generic widespread use of technology and have demonstrated their ability to do so in part by their adoption of the use of tablets for Magistrates. The aim of this current study was to identify the types of digital technology being used in courts and to obtain data from police personnel presenting digital evidence in court. Results: A questionnaire study was conducted in this research to explore current technology used within courtrooms from the perspective of crime scene personnel involved in the presentation of complex crime scene evidence. The study demonstrated that whilst many of the participants currently utilize high-end technological solutions to document their crime scenes, such as 360° photography or laser scanning technologies, their ability to present such evidence was hindered or prevented. This was most likely due to either a lack of existing technology installed in the court, or due to a lack of interoperability between new and existing technology. Conclusion: This study has contributed to this academic field by publishing real life experiences of crime scene examiner’s, who have used advanced technology to record and evaluate crime scenes but are limited in their scope for sharing this information with the court due to technological insufficiency. Contemporary recording techniques have provided the opportunity for further review of crime scenes, which is considered to be a valuable property over previous documentation practice, which relied upon the competency of the investigator to comprehensively capture the scene, often in a single opportunity
UK parliamentary inquiry reports in forensic science – Plus ça change?
Forensic Science provision in England and Wales underpins scientific evidence in many criminal cases. The quality of scientific investigation by scientists and the presentation of science insights has been under scrutiny and it is increasingly established that multiple significant, deep-rooted and persistent issues exist in the Forensic Science ecosystem. A thematic analysis of seven UK parliamentary inquiry reports that addressed Forensic Science and published since 2000, identified key themes and contextual factors. A matrix model that illustrates the connectivity between these themes and factors was produced. The primary issue identified was the challenge of the traditionally narrow focus of inquiries on specific elements of the Forensic Science ecosystem, rather than considering that ecosystem holistically. Through the analysis of these seven inquiry reports, it was possible to develop a matrix which provides a structured framework to critically consider the interconnections, interdependencies and connectivity between the key elements of the Forensic Science ecosystem. The matrix serves to highlight the need for an integrated approach that brings together an understanding of each component of the system and their intersections and connections to address the Forensic Science ecosystem more holistically and address the root causes of key Forensic Science challenges within the criminal justice system. It is hoped that the insights identified in this study offer a starting point for broader discussions and strategic activities across the Forensic Science community to find pathways forward to address persistent deep-seated challenges that have been identified in Forensic Science and find solutions
The adaptation of a 360° camera utilising an alternate light source (ALS) for the detection of biological fluids at crime scenes.
One of the most important and commonly encountered evidence types that can be recovered at crime scenes are biological fluids. Due to the ephemeral nature of biological fluids and the valuable DNA that they can contain, it is fundamental that these are documented extensively and recovered rapidly. Locating and identifying biological fluids can prove a challenging task but can aid in reconstructing a sequence of events. Alternate light sources (ALS) offer powerful non-invasive methods for locating and enhancing biological fluids utilising different wavelengths of light. Current methods for locating biological fluids using ALS's may be time consuming, as they often require close range searching of potentially large crime scenes. Subsequent documentation using digital cameras and alternate light sources can increase the investigation time and due to the cameras low dynamic range, photographs can appear under or over exposed. This study presents a technique, which allows the simultaneous detection and visualisation of semen and saliva utilising a SceneCam 360° camera (Spheron VR AG), which was adapted to integrate a blue Crime Lite XL (Foster+Freeman). This technique was investigated using different volumes of semen and saliva, on porous and non-porous substrates, and the ability to detect these at incremental distances from the substrate. Substrate type and colour had a significant effect on the detection of the biological fluid, with limited fluid detection on darker substrates. The unique real-time High Dynamic range (HDR) ability of the SceneCam significantly enhanced the detection of biological fluids where background fluorescence masked target fluorescence. These preliminary results are presented as a proof of concept for combining 360° photography using HDR and an ALS for the detection of biological stains, within a scene, in real time, whilst conveying spatial relationships of staining to other evidence. This technique presents the opportunity to presumptively screen a crime scene for biological fluids and will facilitate simultaneous location and visualisation of biological evidence
Neural network variational Monte Carlo for positronic chemistry
Quantum chemical calculations of the ground-state properties of
positron-molecule complexes are challenging. The main difficulty lies in
employing an appropriate basis set for representing the coalescence between
electrons and a positron. Here, we tackle this problem with the recently
developed Fermionic neural network (FermiNet) wavefunction, which does not
depend on a basis set. We find that FermiNet produces highly accurate, in some
cases state-of-the-art, ground-state energies across a range of atoms and small
molecules with a wide variety of qualitatively distinct positron binding
characteristics. We calculate the binding energy of the challenging non-polar
benzene molecule, finding good agreement with the experimental value, and
obtain annihilation rates which compare favourably with those obtained with
explicitly correlated Gaussian wavefunctions. Our results demonstrate a generic
advantage of neural network wavefunction-based methods and broaden their
applicability to systems beyond the standard molecular Hamiltonian.Comment: 14 pages, 3 figure
z+: Neutron cross section separation from wide-angle uniaxial polarization analysis from wide-angle uniaxial polarization analysis
We introduce a simple method to extract the nuclear coherent and isotope incoherent, spin incoherent, and magnetic neutron scattering cross section components from powder scattering data measured using a single neutron beam polarization direction and a position-sensitive detector with large out-of-plane coverage. The method draws inspiration from polarized small-angle neutron scattering and contrasts with conventional so-called “ xyz” polarization analysis on wide-angle instruments, which requires measurements with three orthogonal polarization directions. The viability of the method is demonstrated on both simulated and experimental data for the classical “spin ice” system Ho2Ti2O7, the latter from the linear energy transfer direct geometry spectrometer at the International Science Information Service facility. The cross section components can be reproduced with good fidelity by either fitting the out-of-plane angle dependence around a Debye–Scherrer cone or grouping the data by angle and performing a matrix inversion. The limitations of the method and its practical uses are discussed
Increasing the accessibility and impact of justice-related student and practitioner research
Much good quality research by pre-doctoral students and case-work focused practitioners remains unpublished. However, their findings could contribute to the evidence base underpinning science and practice within international justice system contexts. There are two main challenges to making findings accessible: reaching all criminal justice stakeholders, and encouraging collaborative efforts in research addressing ‘real world’ problems.
This article presents the rationale for a new, open access repository. The aim is to share good quality pre-doctoral and practitioner criminal justice research across traditional disciplinary and international borders. Such a repository should be easy to use, well maintained and sustainable. Its reach, value and impact also need to be measurable. We present the major considerations relating to the operation and workflow of such a repository, and outline the potential value, benefits and limitations. Our research suggests that the proposed repository could foster interdisciplinary and collaborative work to benefit global justice systems and societies
Spectrophotometric Determination of Mycophenolate Mofetil as Its Charge-Transfer Complexes with Two π-Acceptors
Two simple, selective, and rapid spectrophotometric methods are described for the determination of mycophenolate mofetil (MPM) in pure form and in tablets. Both methods are based on charge-transfer complexation reaction of MPM with p-chloranilic acid (p-CA) or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in dioxane-acetonitrile medium resulting in coloured product measurable at 520 nm (p-CA) or 580 nm (DDQ). Beer's law is obeyed over the concentration ranges of 40–400 and 12–120 μg mL−1 MPM for p-CA and DDQ, respectively, with correlation coefficients (r) of 0.9995 and 0.9947. The apparent molar absorptivity values are calculated to be 1.06 × 103 and 3.87 × 103 L mol−1 cm−1, respectively, and the corresponding Sandell's sensitivities are 0.4106 and 0.1119 μg cm−1. The limits of detection (LOD) and quantification (LOQ) are also reported for both methods. The described methods were successfully applied to the determination of MPM in tablets. Statistical comparison of the results with those of the reference method showed excellent agreement. No interference was observed from the common excipients present in tablets. Both methods were validated statistically for accuracy and precision. The accuracy and reliability of the methods were further ascertained by recovery studies via standard addition procedure
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