Abstract: Armadillos are bitten by several species of flea. Females of the genus Tunga penetrate the epidermis and when in place are fertilised by males, after which the abdomen swells enormously to form a ’neosome’. Within the penetrans group, T. perforans, makes lesions that perforate the osteoderms within the integument to form ~3 mm diameter cavities occupied by a discoid neosome. We examined these lesions in carapace material from animals which had died in the wild to see whether we could recruit evidence as to how they may be generated, either by the insect or by the host....

Information: A short chapter in the book ‘Conservation of Books’ that discusses polymers encountered in book and paper conservation, their structure and how they deteriorate. Download: No Download available from this site, but you can find a PDF on the web if you look hard enough.

Abstract: Objectives: Differences in the mineral concentration (MC) level of dental enamel may represent a precursor of white spot lesions adjacent to fixed orthodontic brackets. The aim of the current in vitro study was to compare the MC level central, occlusal and cervical to orthodontic attachments. Methods and materials: A total of 16 enamel blocks were obtained from sound human premolar samples extracted for orthodontic reasons. The buccal portion of the dental enamel blocks was divided into central, occlusal, and cervical regions and then imaged and measured to calculate the level of MC using quantitative X-ray microtomography methods (XMT) at each site....

Abstract: Inhalant use disorder is a psychiatric condition characterized by repeated deliberate inhalation from among a broad range of household and industrial chemical products with the intention of producing psychoactive effects. In addition to acute intoxication, prolonged inhalation of fluorinated compounds can cause skeletal fluorosis (SF). We report a young woman referred for hypophosphatasemia and carrying a heterozygous ALPL gene variant (c.457T>C, p.Trp153Arg) associated with hypophosphatasia, the heritable metabolic bone disease featuring impaired skeletal mineralization, who instead suffered from SF....

Abstract: Computational flattening algorithms have been successfully applied to X-ray microtomography scans of damaged historical documents, but have so far been limited to scrolls, books, and documents with one or two folds. The challenge tackled here is to reconstruct the intricate folds, tucks, and slits of unopened letters secured shut with ‘’letterlocking,’’ a practice—systematized in this paper—which underpinned global communications security for centuries before modern envelopes. We present a fully automatic computational approach for reconstructing and virtually unfolding volumetric scans of a locked letter with complex internal folding, producing legible images of the letter’s contents and crease pattern while preserving letterlocking evidence....

Abstract: The coronal portion of the developing upper third molar may be impacted by the developing roots of the second molar. At the relevant age – roughly from 10 to 13 years – both organs are largely soft tissues when and where they collide. It is obviously not possible to obtain tissue from both teeth whilst they are developing, but a frequent after-effect of such collisions is extraction of the third molar....

Abstract: Starting from scratch, if one wanted to correlate light microscopical (LM) and X-ray microtomographic (XMT, micro-CT) findings from the mineralized tissues - bone and calcified cartilage in the skeleton and dentine, enamel, and cementum in teeth - one could simply examine the same, resin embedded sample with at least one flat surface by confocal scanning reflection and/or fluorescence light microscopy and XMT. However, we are frequently presented with ready-made ‘ground’ sections mounted in Canada balsam or DPX on 25mm wide ~1mm thick glass slides with 0....

Abstract: It is presently unclear why there is a high prevalence of periodontal disease (PD) in individuals living with chronic kidney disease (CKD). By employing three different models in rats and mice, we demonstrate that experimental uremia causes periodontal bone loss. Uremia alters the biochemical composition of saliva and induces progressive dysbiosis of the oral microbiota, with microbial samples from uremic animals displaying reduced overall bacterial growth, increased alpha diversity, reduced abundance of key components of the healthy oral microbiota such as Streptococcus and Rothia, and an increase in minor taxa including those from gram-negative phyla Proteobacteria and Bacteroidetes....

Abstract: Many x-ray microtomography.(XMT) studies of human vertebral bone samples have been conducted, but none with high quality, high contrast resolution methodology, which necessarily requires long integration times and, therefore, stable samples. We accessed a collection of 69 ~2mm thick, parasagittal sections of L2 vertebral bodies which were preserved - by embedding in PMMA - under the aegis of the BioMed 1 European project [Bone quality in osteoporosis]. Prior studies using quantitative backscattered electron [qBSE-SEM] imaging had shown a wide spread of local mineralisation density values when sampled at one cubic micrometer [1 fl] resolution, but only in 2D section planes....

Abstract: In linearly polarised light (LPL), birefringent structures appear brightest if they lie both in the plane of the section and at 45° / 135° to the axes of the crossed polarising filter elements, but dark if perpendicular to the section plane or parallel to either polarizer or analyser, preventing measurement of the whole scene at once because nothing can be resolved in the dark sectors of the ‘Maltese cross’. This may be solved using circularly polarised light (CPL), when dip with respect to the section-plane may be quantified for plane parallel sections and we can use pseudocolour to produce dip maps....

Abstract: Healthy connective tissues are covered and protected by an epithelium. The single unavoidable exception concerns cementum and dentine at the neck of a tooth after the epithelial attachment migrates past the enamel. Carious lesions break this barrier and microbial invasion via dentine and pulp leads to pulpitis, osteomyelitis and extraction. Similarly, tooth loss from periodontal disease may leave infected bone. Dental implants may thus be placed in prejudiced bone. In the context of this symposium, therefore, the peri-implant disease may be nucleated before the outset....

Abstract: The feasibility of a thin-wire torsion stress-strain experiment with nanostrain sensitivity is demonstrated. A gauge length of 50 metres was made possible by using The Monument, London, thereby restoring it to its original purpose as a scientific instrument. A wire of 150µm diameter was studied using the load-unload method and data was recorded in the elastic regime and through the elastic-plastic transition. Analysis of this preliminary experiment suggested some necessary improvements to the equipment and methods....

Abstract: Presentation and poster at Microscience Microscopy Congress, Manchester, July 2nd - 4th 2019 Download: [Paper](/papers/boyde2019newtissuesboyde2019newtissues.pdf

Information: Fully revised, reordered and updated this is the latest book for those studying for their Intermediate Amateur radio licence. The Intermediate Licence Manual contains all of the information required for those seeking to upgrade their Foundation callsign. Designed to cover all elements of the Amateur Radio Intermediate licence syllabus, this second RSGB course-book The Intermediate Licence Manual is written in an easy to understand style. Broken down into familiar chapters such as Licence Conditions, Basic Electronics, Transmitters & Receivers and Antennas....

Abstract: Artificial teeth have several advantages in preclinical training. The aim of this study is to three-dimensionally (3D) print accurate artificial teeth using scans from X-ray microtomography (XMT). Extracted and artificial teeth were imaged at 90 kV and 40 kV, respectively, to create detailed high contrast scans. The dataset was visualised to produce internal and external meshes subsequently exported to 3D modelling software for modification before finally sending to a slicing program for printing....

Abstract Objectives:: The objective of this in vitro study was to quantify the amount of mineral change in demineralized dentin at pH 5.5 after the application of dental varnishes containing fluoride with casein phosphopeptide-amorphous calcium phosphate, fluoride and bioglass, or fluoride alone. Methods and materials:: A total of 12 extracted human sound mandibular premolar root samples were coated with an acid-resistant varnish, leaving a 2 × 3 mm window at the outer root surface....

Abstract: Abstract for poster P25 presented at Bone Research Society, Winchester 28/6/2018 All that fractures is not bone: microscopic anatomy of vertebral bodies. Objectives: To understand interface between cortical shell and cancellous bone in human vertebral bodies, age changes, and probable mechanical significance. Archival material, 3-4 mm mid-body vertical slices, 80 L2 embedded PMMA: blocks polished, carbon coated, 20 kV qBSE SEM; high contrast resolution x-ray microtomography (XMT: 44 hour scans); iodine vapour staining and further BSE SEM, uncoated....

Abstract: Purpose: Cracks in bone and articular calcified cartilage (ACC) of the subchondral plate heal by intercalation of a highly mineralised infill material which disappears with demineralisation. This material may also extruded into hyaline articular cartilage (HAC) as High Density Mineralised Protrusions (HDMPs), which may fragment and act as a cutting and grinding agent, damaging HAC from within. We wish to know more about the structure and composition of HDMPs. We have prepared very thin sections from the front face of bone blocks embedded in PMMA - which had previously been studied by backscattered electron scanning electron microscopy (BSE-SEM) and x-ray microtomography (XMT) - by the new technique of laser-ablation machining and wanted to know if this method could be applied to this rather intractable problem....

Abstract: Abstract for Anatomists on the edge meeting, Galway, 27-29 June 2017. Journal of Anatomy Volume 232, Issue 2 S29 Qualitative studies of the calcified tissues in the lumbar vertebral body of the ageing human. We studied the degree of mineralisation of trabecular and cortical bone and cartilage and thickness of the cortex in lumbar vertebral bodies. We report correlated 3D microscopic imaging methods concerning osteoporotic changes. We examined 34 archival macerated para‐sagittal slices of L4 (17 male, 17 female) by 3D BSE‐SEM and 69 L2 (38 male, 31 female, 70 $pm$ 15 years) obtained through European Union Concerted Action Biomed 1 ‘Assessment of bone quality in osteoporosis’, which were embedded in PMMA: plane block surfaces were carbon coated for quantitative 20 kV backscattered electron scanning electron microscopy (qBSE‐SEM); and later polished and stained with iodine vapour to study uncalcified matrix, providing very high resolution imaging of entire vertical sections....

Abstract: The present study began by examining variations in the degree of mineralisation of ‘bone’ in lumbar vertebral bodies. Thick para-sagittal slices of L2 (38 male, 31 female, 70 ± 15 years); embedded PMMA; plane block surfaces carbon coated; quantitative 20kV BSE SEM; then polished and stained with iodine vapour to reveal (uncoated, at 50Pa) uncalcified matrix. Stitching allowed high resolution imaging of entire vertical sections. High-contrast x-ray microtomography (XMT, n = 15) was conducted at 30 micron voxel resolution....