Applications of Electron Backscatter Diffraction (EBSD) in Archaeology

Electron backscattered diffraction (EBSD) has been used to study samples of archaeological gold, silver, copper and bronze prepared using simple metallographic etches. EBSD maps of orientation and local misorientation revealed the metals’ microstructures and deformation substructures, and from this, combined in some cases with information on the crystallographic texture (also determined by EBSD), the methods of manufacture and working of the artefacts were determined. EBSD was also used to examine discontinuous precipitation at grain boundaries in a silver alloy at a high resolution

Microstructures of cast silver-copper alloy archaeological artefacts

Cast silver-copper alloys objects form a significant part of the archaeological record from the first millenium BC onwards. Although age hardening of annealed and quenched material has been well studied there has been little study of cast microstructures. This work used a combination of scanning electron microscopy (SEM), electron backscattered diffraction (EBSD) and optical microscopy (OM) to explore the range of microstructures in archaeological cast silver and compare them with those in modern cast silver. Modern cast silver showed extensive fine scale precipitation of copper within the grains which was unconnected to the copper-rich phase of the primary eutectic. Ancient cast objects displayed a wide range of microstructures, some very similar to the modern cast silver but some quite different. EBSD allowed interpretation of the microstructure close to some grain boundaries whose detail was obscured by the cast structure in OM and SEM images. Orientation images showed fine-scale interpenetration of the adjoining grains suggesting cellular growth, suggesting that over archaeological time boundary modification may take place in cast as well as wrought and annealed structures

Re-examination of the value of the Kapeller-Adler pregnancy diagnosis test (histidinuria) as an instrument of differential diagnosis, with special reference to mental diseases

326 urines (193 males, 133 females) were tested by means of the newest Kapeller-Adler test for the presence of histidine. In the case of normal pregnancy the reaction was invariably positive; in those derived from non -pregnant healthy individuals it was equally invariably and unequivocally negative. In 14 out of 299 cases of diseases of various kinds, histidin-uria was demonstrated. It would seem that histidinuria is indicative of dysfunction of the pituitary or of the liver for tests for histidinuria cannot claim to possess any real value in differential diagnosis of diseases

Klein's Curve

By giving an homology basis well adapted to the symmetries of Klein's curve, presented as a plane curve, we derive a new expression for its period matrix. This is explicitly related to the hyperbolic model and results of Rauch and Lewittes.Comment: 16 pages 5 figures. Final version makes connection with other known period matrice

Electron backscatter diffraction (EBSD) measurement of accumulated strain

Reliable life prediction depends on a sound knowledge of the accumulated strain in components subject to creep. Electron backscatter diffraction (EBSD) is now well-established for estimating/measuring plastic strain and there have been a number of different EBSD metrics proposed for this. Microstructure has a strong effect on the calibration of most of these, limiting their use in critical areas such as around welds where microstructure is inhomogeneous. During the service life of materials such as 316 steel there is extensive precipitation but most published applications of EBSD are on precipitate-free materials. A systematic study has been made on the applicability of different EBSD metrics to both solution-annealed and service-aged 316H stainless steel subject to a range of plastic and creep strains between 0 and 35% to determine the conditions for maximum strain sensitivity of each. A simple new method of assessing cumulative strain, ‘deformed grain fraction’ (DGF) is presented and DGF has been compared with more conventional EBSD strain metrics. In 316H steel with a range of microstructures the effects of plastic and creep strains are additive for all metrics. DGF is relatively insensitive to changes in microstructure and its use is demonstrated in measuring total plastic strain in ex-service welded components

Hypoxia-inducible factor-1α and -2α are expressed in most rectal cancers but only hypoxia-inducible factor-1α is associated with prognosis

The hypoxia-mediated response of tumours is a major determining factor in growth and metastasis. Understanding tumour biology under hypoxic conditions is crucial for the development of antiangiogenic therapy. Using one of the largest cohorts of rectal adenocarcinomas to date, this study investigated hypoxia-inducible factor-1α (HIF-1α) and HIF-2α protein expression in relation to rectal cancer recurrence and cancer-specific survival. Patients (n=90) who had undergone surgery for rectal adenocarcinoma, with no prior neoadjuvant therapy or metastatic disease, and for whom adequate follow-up data were available were selected. Microvessel density (MVD), HIF-1α and HIF-2α expressions were assessed immunohistologically with the CD34 antibody for vessel identification and the NB100-131B and NB100-132D3 antibodies for HIF-1α and HIF-2α, respectively. In a multifactorial analysis, results were correlated with tumour stage, recurrence rate and long-term survival. Microvessel density was higher across T and N stages (P<0.001) and associated with poor survival (hazard ratio (HR)=8.7, P<0.005) and decreased disease-free survival (HR=4.7, P<0.005). hypoxia-inducible factor-1α and -2α were expressed in >50% of rectal cancers (HIF-1α, 54%, 48/90; HIF-2α, 64%, 58/90). HIF-1α positivity was associated with both TNM stage (P<0.05) and vascular invasion (P<0.005). In contrast, no associations were shown between HIF-2α expression and any pathological features, and HIF-1α positivity had no effect on outcome. The study showed an independent association between HIF-1α expression and advanced TNM stage with poor outcome. Our results indicate that HIF-1α, but not HIF-2α, might be used as a marker of prognosis, in addition to methods currently used, to enhance patient management

Morphological and molecular description of Ixodes woyliei n. sp. (Ixodidae) with consideration for co-extinction with its critically endangered marsupial host

Background Taxonomic identification of ticks obtained during a longitudinal survey of the critically endangered marsupial, Bettongia penicillata Gray, 1837 (woylie, brush-tailed bettong) revealed a new species of Ixodes Latrielle, 1795. Here we provide morphological data for the female and nymphal life stages of this novel species (Ixodes woyliei n. sp.), in combination with molecular characterisation using the mitochondrial cytochrome c oxidase subunit 1 gene (cox1). In addition, molecular characterisation was conducted on several described Ixodes species and used to provide phylogenetic context. Results Ixodes spp. ticks were collected from the two remaining indigenous B. penicillata populations in south-western Australia. Of 624 individual B. penicillata sampled, 290 (47%) were host to ticks of the genus Ixodes; specifically I. woyliei n. sp., I. australiensis Neumann, 1904, I. myrmecobii Roberts, 1962, I. tasmani Neumann, 1899 and I. fecialis Warburton & Nuttall, 1909. Of these, 123 (42%) were host to the newly described I. woyliei n. sp. In addition, 268 individuals from sympatric marsupial species (166 Trichosurus vulpecula hypoleucus Wagner, 1855 (brushtail possum), 89 Dasyurus geoffroii Gould, 1841 (Western quoll) and 13 Isoodon obesulus fusciventer Gray, 1841 (southern brown bandicoot)) were sampled for ectoparasites and of these, I. woyliei n. sp. was only found on two I. o. fusciventer. Conclusions Morphological and molecular data have confirmed the first new Australian Ixodes tick species described in over 50 years, Ixodes woyliei n. sp. Based on the long-term data collected, it appears this tick has a strong predilection for B. penicillata, with 42% of Ixodes infections on this host identified as I. woyliei n. sp. The implications for this host-parasite relationship are unclear but there may be potential for a future co-extinction event. In addition, new molecular data have been generated for collected specimens of I. australiensis, I. tasmani and museum specimens of I. victoriensis Nuttall, 1916, which for the first time provides molecular support for the subgenus Endopalpiger Schulze, 1935 as initially defined. These genetic data provide essential information for future studies relying on genotyping for species identification or for those tackling the phylogenetic relationships of Australian Ixodes species

General practice vs surgical-based follow-up for patients with colon cancer: randomised controlled trial

This trial examined the optimal setting for follow-up of patients after treatment for colon cancer by either general practitioners or surgeons. In all, 203 consenting patients who had undergone potentially curative treatment for colon cancer were randomised to follow-up by general practitioners or surgeons. Follow-up guidance recommended three monthly clinical review and annual faecal occult blood tests (FOBT) and were identical in both study arms. Primary outcome measures (measured at baseline, 12 and 24 months were (1) quality of life, SF-12; physical and mental component scores, (2) anxiety and depression: Hospital Anxiety and Depression Scale and (3) patient satisfaction: Patient Visit-Specific Questionnaire. Secondary outcomes (at 24 months) were: investigations, number and timing of recurrences and deaths. In all, 170 patients were available for follow-up at 12 months and 157 at 24 months. At 12 and 24 months there were no differences in scores for quality of life (physical component score, P=0.88 at 12 months; P=0.28 at 24 months: mental component score, P=0.51, P=0.47; adjusted), anxiety (P=0.72; P=0.11) depression (P=0.28; P=0.80) or patient satisfaction (P=0.06, 24 months). General practitioners ordered more FOBTs than surgeons (rate ratio 2.4, 95% CI 1.4–4.4), whereas more colonoscopies (rate ratio 0.7, 95% CI 0.5–1.0), and ultrasounds (rate ratio 0.5, 95% CI 0.3–1.0) were undertaken in the surgeon-led group. Results suggest similar recurrence, time to detection and death rates in each group. Colon cancer patients with follow-up led by surgeons or general practitioners experience similar outcomes, although patterns of investigation vary

Spinal involvement in mucopolysaccharidosis IVA (Morquio-Brailsford or Morquio A syndrome): presentation, diagnosis and management.

Mucopolysaccharidosis IVA (MPS IVA), also known as Morquio-Brailsford or Morquio A syndrome, is a lysosomal storage disorder caused by a deficiency of the enzyme N-acetyl-galactosamine-6-sulphate sulphatase (GALNS). MPS IVA is multisystemic but manifests primarily as a progressive skeletal dysplasia. Spinal involvement is a major cause of morbidity and mortality in MPS IVA. Early diagnosis and timely treatment of problems involving the spine are critical in preventing or arresting neurological deterioration and loss of function. This review details the spinal manifestations of MPS IVA and describes the tools used to diagnose and monitor spinal involvement. The relative utility of radiography, computed tomography (CT) and magnetic resonance imaging (MRI) for the evaluation of cervical spine instability, stenosis, and cord compression is discussed. Surgical interventions, anaesthetic considerations, and the use of neurophysiological monitoring during procedures performed under general anaesthesia are reviewed. Recommendations for regular radiological imaging and neurologic assessments are presented, and the need for a more standardized approach for evaluating and managing spinal involvement in MPS IVA is addressed