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Hutchinson J.C.,University College London | Arthurs O.J.,University College London | Ashworth M.T.,University College London | Ramsey A.T.,Nikon Metrology Inc. | And 3 more authors.
Ultrasound in Obstetrics and Gynecology | Year: 2016

Objectives Congenital cardiac malformations are commonly identified at perinatal autopsy, which can be challenging in fetuses of early gestation and in macerated fetuses. Our objective was to examine fetal complex congenital heart disease by microcomputed tomography (micro-CT), using standard autopsy as the gold standard. Methods In this ethically approved study, ex-vivo isolated fetal heart and fetal heart-lung blocks underwent iodine preparation prior to micro-CT, and were fixed in formalin after the micro-CT examination. Images were acquired using a microfocus-CT scanner with individual specimen image optimization. Twenty-one indices assessed normally at autopsy were evaluated for each dataset. Cardiac dissection was performed using a dissecting microscope within 24 h of the micro-CT examination. Results We examined six fetal hearts, comprising five with complex congenital cardiac malformations at a gestational age of 17-23 weeks and an anatomically normal heart of 23 weeks' gestation for reference. All specimens demonstrated excellent internal contrast at micro-CT examination, and the correct overall diagnosis was made in all cases. There was agreement for 114/126 indices assessed on micro-CT and at autopsy dissection (overall concordance of 95.8% (95% CI, 90.5-98.2%)). Micro-CT was particularly useful in the assessment of ventricular morphology in macerated fetuses. Conclusions Micro-CT of small ex-vivo fetal specimens can provide highly accurate three-dimensional rendering of complex congenital fetal heart disease. This approach represents a significant advance in postmortem imaging and confirms the potential of this technology for non-invasive examination of small fetuses and organs. © Copyright 2015 ISUOG. Published by John Wiley & Sons Ltd. Source

Bourque J.A.,Nikon Metrology Inc. | Edwards D.,JEOL United States Inc.
SMT Surface Mount Technology Magazine | Year: 2012

The investigation of high-density surface-mount devices has been made easier with new techniques and equipment that allow an individual to correlate findings from one instrument to another; from optical to X-ray and CT to SEM. Add to that improved ease of use and automation and the individual can focus on being an investigator rather than an instrument or process specialist. Source

Ramsey A.,Nikon Metrology Inc. | Houston T.F.,Western Australian Museum | Ball A.D.,Natural History Museum in London | Goral T.,Natural History Museum in London | And 2 more authors.
Anatomical Record | Year: 2015

Working on the hypothesis that an important function of the lamellate antennae of adult male beetles belonging to the genus Rhipicera is to detect scent associated with female conspecifics, and using field observations, anatomical models derived from X-ray microcomputed tomography, and scanning electron microscopy, we have investigated the behavioral, morphological, and morphometric factors that may influence molecule capture by these antennae. We found that male beetles fly upwind in a zigzag manner, or face upwind when perching, behavior consistent with an animal that is tracking scent. Furthermore, the ultrastructure of the male and female antennae, like their gross morphology, is sexually dimorphic, with male antennae possessing many more of a particular type of receptor-the sensillum placodeum-than their female counterparts (approximately 30,000 vs. 100 per antenna, respectively). Based on this disparity, we assume that the sensilla placodea on the male antennae are responsible for detecting scent associated with female Rhipicera beetles. Molecule capture by male antennae in their alert, fanned states is likely to be favoured by: (a) male beetles adopting prominent, upright positions on high points when searching for scent; (b) the partitioning of antennae into many small segments; (c) antennal morphometry (height, width, outline area, total surface area, leakiness, and narrow channels); (d) the location of the sensilla placodea where they are most likely to encounter odorant molecules; and (e) well dispersed sensilla placodea. The molecule-capturing ability of male Rhipicera antennae may be similar to that of the pectinate antennae of certain male moths. © 2015 Wiley Periodicals, Inc. Source

Howard L.E.,Natural History Museum in London | Holmes W.M.,University of Glasgow | Ferrando S.,University of Genoa | Maclaine J.S.,Natural History Museum in London | And 4 more authors.
Journal of Morphology | Year: 2013

Holocephalans (chimaeras) are a group of marine fishes comprising three families: the Callorhinchidae (callorhinchid fishes), the Rhinochimaeridae (rhinochimaerid fishes) and the Chimaeridae (chimaerid fishes). We have used X-ray microcomputed tomography and magnetic resonance imaging to characterise in detail the nasal anatomy of three species of chimaerid fishes: Chimaera monstrosa, C. phantasma and Hydrolagus colliei. We have shown that the nasal chamber of these three species is linked to the external environment by an incurrent channel and to the oral cavity by an excurrent channel via an oral groove. A protrusion of variable morphology is present on the medial wall of the incurrent channel in all three species, but is absent in members of the two other holocephalan families that we inspected. A third nasal channel, the lateral channel, functionally connects the incurrent nostril to the oral cavity, by-passing the nasal chamber. From anatomical reconstructions, we have proposed a model for the circulation of water, and therefore the transport of odorant, in the chimaerid nasal region. this model, water could flow through the nasal region via the nasal chamber or the lateral channel. either case, the direction of flow could be reversed. Circulation through the entire nasal region is likely to be driven primarily by the respiratory pump. We have identified several anatomical features that may segregate, distribute, facilitate and regulate flow in the nasal region and have considered the consequences of flow reversal. The non-sensory cilia lining the olfactory sensory channels appear to be mucus-propelling, suggesting that these cilia have a common protective role in cartilaginous fishes (sharks, rays and chimaeras). The nasal region of chimaerid fishes shows at least two adaptations to a benthic lifestyle, and suggests good olfactory sensitivity, with secondary folding enhancing the hypothetical flat sensory surface area by up to 70%. © 2013 Wiley Periodicals, Inc. Source

Smith D.G.,Nikon Research Corporation of America | Slotwinski A.,Nikon Metrology Inc. | Hedges T.,Nikon Metrology Inc.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

The Nikon Metrology Laser Radar system focuses a beam from a fiber to a target object and receives the light scattered from the target through the same fiber. The system can, among other things, make highly accurate measurements of the position of a tooling ball by locating the angular position of peak signal quality, which is related to the fiber coupling efficiency. This article explores the relationship between fiber coupling efficiency and focus condition. © 2015 SPIE. Source

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