A survey of case studies on the use of forensic three-dimensional printing in England and Wales

3D printing has rapidly developed and been applied in forensic science due to its use in creating demonstrations for courts of law. Much of the literature on this specific topic has focused on the use of 3D printed models in academia, the potential influence on a jury, and its use as a long-term documentation process, but with few actual forensic case examples. This paper offers an insight into the development of 3D printing in forensic practice and how 3D printing is currently being used in the criminal justice system in England and Wales. A series of case reports were gathered from multiple police forces and forensic practitioners in the UK to identify how 3D printing was being used. These discussions established who was requesting 3D printed exhibits, what type of technologies were being utilised, what type of exhibits were being printed, and resulting feedback for the use of 3D printed material within a criminal case. As a result, this research demonstrates the current use of 3D printing in England and Wales, discussing the associated cases that have been known to incorporate 3D prints. Likewise, this work explores the limitations that have been encountered by forensic practitioners and identifies a series of research questions that should be considered in future investigations

Detection of involved margins in breast specimens with x-ray phase-contrast computed tomography

Margins of wide local excisions in breast conserving surgery are tested through histology, which can delay results by days and lead to second operations. Detection of margin involvement intraoperatively would allow the removal of additional tissue during the same intervention. X-ray phase contrast imaging (XPCI) provides soft tissue sensitivity superior to conventional X-rays: we propose its use to detect margin involvement intraoperatively. We have developed a system that can perform phase-based computed tomography (CT) scans in minutes, used it to image 101 specimens approximately half of which contained neoplastic lesions, and compared results against those of a commercial system. Histological analysis was carried out on all specimens and used as the gold standard. XPCI-CT showed higher sensitivity (83%, 95% CI 69–92%) than conventional specimen imaging (32%, 95% CI 20–49%) for detection of lesions at margin, and comparable specificity (83%, 95% CI 70–92% vs 86%, 95% CI 73–93%). Within the limits of this study, in particular that specimens obtained from surplus tissue typically contain small lesions which makes detection more difficult for both methods, we believe it likely that the observed increase in sensitivity will lead to a comparable reduction in the number of re-operations

Detection of involved margins in breast specimens with X-ray phase-contrast computed tomography.

Margins of wide local excisions in breast conserving surgery are tested through histology, which can delay results by days and lead to second operations. Detection of margin involvement intraoperatively would allow the removal of additional tissue during the same intervention. X-ray phase contrast imaging (XPCI) provides soft tissue sensitivity superior to conventional X-rays: we propose its use to detect margin involvement intraoperatively. We have developed a system that can perform phase-based computed tomography (CT) scans in minutes, used it to image 101 specimens approximately half of which contained neoplastic lesions, and compared results against those of a commercial system. Histological analysis was carried out on all specimens and used as the gold standard. XPCI-CT showed higher sensitivity (83%, 95% CI 69-92%) than conventional specimen imaging (32%, 95% CI 20-49%) for detection of lesions at margin, and comparable specificity (83%, 95% CI 70-92% vs 86%, 95% CI 73-93%). Within the limits of this study, in particular that specimens obtained from surplus tissue typically contain small lesions which makes detection more difficult for both methods, we believe it likely that the observed increase in sensitivity will lead to a comparable reduction in the number of re-operations

Volumetric high-resolution X-ray phase-contrast virtual histology of breast specimens with a compact laboratory system

The assessment of margin involvement is a fundamental task in breast conserving surgery to prevent recurrences and reoperations. It is usually performed through histology, which makes the process time consuming and can prevent the complete volumetric analysis of large specimens. X-ray phase contrast tomography combines high resolution, sufficient penetration depth and high soft tissue contrast, and can therefore provide a potential solution to this problem. In this work, we used a high-resolution implementation of the edge illumination X-ray phase contrast tomography based on "pixel-skipping" X-ray masks and sample dithering, to provide high definition virtual slices of breast specimens. The scanner was originally designed for intra-operative applications in which short scanning times were prioritised over spatial resolution; however, thanks to the versatility of edge illumination, high-resolution capabilities can be obtained with the same system simply by swapping x-ray masks without this imposing a reduction in the available field of view. This makes possible an improved visibility of fine tissue strands, enabling a direct comparison of selected CT slices with histology, and providing a tool to identify suspect features in large specimens before slicing. Combined with our previous results on fast specimen scanning, this works paves the way for the design of a multi-resolution EI scanner providing intra-operative capabilities as well as serving as a digital pathology system

A ‘spoon full of sugar’ helps the medicine go down: how a participant friendly version of a psychophysics task significantly improves task engagement, performance and data quality in a typical adult sample

Few would argue that the unique insights brought by studying the typical and atypical development of psychological processes are essential to building a comprehensive understanding of the brain. Often, however, the associated challenges of working with non-standard adult populations results in the more complex psychophysical paradigms being rejected as too complex. Recently we created a child (and clinical group) friendly implementation of one such technique – the reverse correlation Bubbles approach and noted an associated performance boost in adult participants. Here, we compare the administration of three different versions of this participant-friendly task in the same adult participants to empirically confirm that introducing elements in the experiment with the sole purpose of improving the participant experience, not only boost the participant’s engagement and motivation for the task but results in significantly improved objective task performance and stronger statistical results

Genomic Analysis of Parent-of-Origin Allelic Expression in Arabidopsis thaliana Seeds

Differential expression of maternally and paternally inherited alleles of a gene is referred to as gene imprinting, a form of epigenetic gene regulation common to flowering plants and mammals. In plants, imprinting primarily occurs in the endosperm, a seed tissue that supports the embryo during its growth and development. Previously, we demonstrated that widespread DNA demethylation at remnants of transposable elements accompanies endosperm development and that a subset of these methylation changes are associated with gene imprinting. Here we assay imprinted gene expression genome-wide by performing high-throughput sequencing of RNA derived from seeds of reciprocal intraspecific crosses. We identify more than 200 loci that exhibit parent-of-origin effects on gene expression in the endosperm, including a large number of transcription factors, hormone biosynthesis and response genes, and genes that encode regulators of epigenetic information, such as methylcytosine binding proteins, histone methyltransferases, and chromatin remodelers. The majority of these genes are partially, rather than completely, imprinted, suggesting that gene dosage regulation is an important aspect of imprinted gene expression

Laboratory-based x-ray phase contrast CT technology for clinical intra-operative specimen imaging

The design of an X-ray phase contrast tomography system for intra-operative specimen imaging based on edge illumination is presented. The use of edge illumination makes possible working with large focus, polychromatic X-ray sources reducing acquisition times of tomography scans down to values compatible with clinical use, while maintaining phase sensitivity in a compact device. The results collected so far show that application of this technology to breast conservation surgery has great potential to reduce re-operations, thus saving additional costs for healthcare services and stress for patients

Intra-Operative Assessment of Cancer with X-Ray Phase Contrast Computed Tomography

X-ray Phase-Contrast Computed Tomography (PC-CT) increases contrast in weakly attenuating samples, such as soft tissues. In Edge-Illumination (EI) PC-CT, phase effects are accessed from amplitude modulation of the x-ray beam using alternating transmitting and attenuating masks placed prior to the sample and detector. A large field of view PC-CT scanner using this technique was applied to two areas of cancer assessment, namely excised breast and esophageal tissue. For the breast tissue, Wide Local Excisions (WLEs) were studied intra-operatively using PC-CT for the evaluation of tumor removal in breast conservation surgery. Images were acquired in 10 minutes without compromising on image quality, showing this can be used in a clinical setting. Longer, higher resolution PC-CT images were also taken, with analysis showing previously undetected thinning of tumor strands. This would allow a second use of the system for “virtual histopathology”, outside of surgery. For the esophagus samples, tissues were taken from esophagectomy surgery, where the lower part of the esophagus is removed, and the stomach relocated. For the assessment of ongoing therapy, accurate staging of tumors in the removed esophagus is essential, with the current gold standard provided by histopathology. PCCT images were acquired on several samples and compare well with histopathology, with both modalities showing similar features. Examples are shown where staging of tumor penetration is possible with PC-CT images alone, which is hoped will be an important step in performing the imaging and staging intra-operatively

Patient safety in elderly hip fracture patients: design of a randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>The clinical environment in which health care providers have to work everyday is highly complex; this increases the risk for the occurrence of unintended events. The aim of this randomised controlled trial is to improve patient safety for a vulnerable group of patients that have to go through a complex care chain, namely elderly hip fracture patients.</p> <p>Methods/design</p> <p>A randomised controlled trial that consists of three interventions; these will be implemented in three surgical wards in Dutch hospitals. One surgical ward in another hospital will be the control group. The first intervention is aimed at improving communication between care providers using the SBAR communication tool. The second intervention is directed at stimulating the role of the patient within the care process with a patient safety card. The third intervention consists of a leaflet for patients with information on the most common complications for the period after discharge. The primary outcome measures in this study are the incidence of complications and adverse events, mortality rate within six months after discharge and functional mobility six months after discharge. Secondary outcome measures are length of hospital stay, quality and completeness of information transfer and patient satisfaction with the instruments.</p> <p>Discussion</p> <p>The results will give insight into the nature and scale of complications and adverse events that occur in elderly hip fracture patients. Also, the implementation of three interventions aimed at improving the communication and information transfer provides valuable possibilities for improving patient safety in this increasing patient group. This study combines the use of three interventions, which is an innovative aspect of the study.</p> <p>Trial registration</p> <p>The Netherlands National Trial Register <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1562">NTR1562</a></p

Was Wright Right? The Canonical Genetic Code is an Empirical Example of an Adaptive Peak in Nature; Deviant Genetic Codes Evolved Using Adaptive Bridges

The canonical genetic code is on a sub-optimal adaptive peak with respect to its ability to minimize errors, and is close to, but not quite, optimal. This is demonstrated by the near-total adjacency of synonymous codons, the similarity of adjacent codons, and comparisons of frequency of amino acid usage with number of codons in the code for each amino acid. As a rare empirical example of an adaptive peak in nature, it shows adaptive peaks are real, not merely theoretical. The evolution of deviant genetic codes illustrates how populations move from a lower to a higher adaptive peak. This is done by the use of “adaptive bridges,” neutral pathways that cross over maladaptive valleys by virtue of masking of the phenotypic expression of some maladaptive aspects in the genotype. This appears to be the general mechanism by which populations travel from one adaptive peak to another. There are multiple routes a population can follow to cross from one adaptive peak to another. These routes vary in the probability that they will be used, and this probability is determined by the number and nature of the mutations that happen along each of the routes. A modification of the depiction of adaptive landscapes showing genetic distances and probabilities of travel along their multiple possible routes would throw light on this important concept