638 research outputs found

    Autofluorescence lifetime augmented reality as a means for real-time robotic surgery guidance in human patients.

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    Due to loss of tactile feedback the assessment of tumor margins during robotic surgery is based only on visual inspection, which is neither significantly sensitive nor specific. Here we demonstrate time-resolved fluorescence spectroscopy (TRFS) as a novel technique to complement the visual inspection of oral cancers during transoral robotic surgery (TORS) in real-time and without the need for exogenous contrast agents. TRFS enables identification of cancerous tissue by its distinct autofluorescence signature that is associated with the alteration of tissue structure and biochemical profile. A prototype TRFS instrument was integrated synergistically with the da Vinci Surgical robot and the combined system was validated in swine and human patients. Label-free and real-time assessment and visualization of tissue biochemical features during robotic surgery procedure, as demonstrated here, not only has the potential to improve the intraoperative decision making during TORS but also other robotic procedures without modification of conventional clinical protocols

    Evaluation of tantalum for mercury containment in the SNAP-8 boiler

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    Corrosion testing of tantalum for mercury containment in SNAP 8 boile

    Population pharmacokinetics-based recommendations for a single delayed or missed dose of nusinersen

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    Nusinersen is an antisense oligonucleotide approved for the treatment of spinal muscular atrophy. The drug is given intrathecally at 12 mg, beginning with 3 loading doses at 2-week intervals, a fourth loading dose 30 days thereafter, and maintenance doses at 4-month intervals. This population pharmacokinetic model was developed to clarify how to maintain targeted nusinersen exposure after an unforeseen one-time delay or missed dose. Simulations demonstrated that the impact of a one-time delay in dosing or a missed dose on median cerebrospinal fluid exposures depended on duration of interruption and the regimen phase in which it occurred. Delays in loading doses delayed reaching the peak trough concentration by approximately the duration of the interruption. Resumption of the regimen as soon as possible resulted in achieving steady state trough concentration upon completion of the loading phase. A short delay (30-90 days) during the maintenance phase led to prolonged lower median cerebrospinal fluid concentration if all subsequent doses were shifted by the same 4-month interval. However, administration of the delayed dose, followed by the subsequent dose as originally scheduled, rapidly restored trough concentration. If a dose must be delayed, patients should return to the original dosing schedule as soon as possible

    Contextual factors among indiscriminate or larger attacks on food or water supplies, 1946-2015

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    This research updates previous inventories of malicious attacks on food and water to include data from 1946 through mid-2015. A systematic search of news reports, databases and previous inventories of poisoning events was undertaken. Incidents that threatened or were intended to achieve direct harm to humans, and that were either relatively large (number of victims > 4 or indiscriminate in intent or realisation were included. Agents could be chemical, biological or radio-nuclear. Reports of candidate incidents were subjected to systematic inclusion and exclusion criteria as well as validity analysis (not always clearly undertaken in previous inventories of such attacks). We summarise contextual aspects of the attacks that may be important for scenario prioritisation, modelling and defensive preparedness. Opportunity is key to most realised attacks, particularly access to dangerous agents. The most common motives and relative success rate in causing harm were very different between food and water attacks. The likelihood that people were made ill or died also varied by food/water mode, and according to motive and opportunity for delivery of the hazardous agent. Deaths and illness associated with attacks during food manufacture and prior to sale have been fewer than those in some other contexts. Valuable opportunities for food defence improvements are identified in other contexts, especially food prepared in private or community settings

    Stringy Toda Cosmologies

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    We discuss a particular stringy modular cosmology with two axion fields in seven space-time dimensions, decomposable as a time and two flat three-spaces. The effective equations of motion for the problem are those of the SU(3)SU(3) Toda molecule, and hence are integrable. We write down the solutions, and show that all of them are singular. They can be thought of as a generalization of the Pre-Big-Bang cosmology with excited internal degrees of freedom, and still suffering from the graceful exit problem. Some of the solutions however show a rather unexpected property: some of their spatial sections shrink to a point in spite of winding modes wrapped around them. We also comment how more general, anisotropic, solutions, with fewer Killing symmetries can be obtained with the help of STU dualities.Comment: 22 pages, latex, no figures. Several minor typos correcte

    Paget's disease of bone in two medieval skeletons from Poulton Chapel, Cheshire, UK

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    Paget's disease of bone (PDB) is a chronic, metabolic disease disrupting normal bone turnover and is reported as one of the most common bone diseases after osteoporosis. PDB is characterised by excessive bone remodelling resulting in bone enlargement, fragility, deformity and additional complications. Typically, PDB affects one or a few bones of the axial skeleton and is commonly recorded in older individuals (over 55 years of age) affecting more males than females. Although PDB has been reported worldwide, there is a high concentration of reported cases in the UK, with a regional hotspot in the northwest of England. This study reviews an adult male (SK463) and female (SK750) with skeletal lesions of PDB from Poulton Chapel, Cheshire. Full macroscopic and radiographic analysis has identified the skeletal distribution of PDB, with up to 75% of both skeletons affected. SK463 presents noticeable anterior bowing to both tibiae, likely the result of PDB. AMS radiocarbon dating and stable isotope analysis performed on teeth samples confirmed that both individuals' dates were medieval, had a mixed/varied diet and were local to the northwest of England. This research adds to the emerging paleopathological literature on PDB, while providing additional support for the identification of a geographical hotspot observed in contemporary populations

    Diving And Amphibious Behaviour In Free-Living Crocodylus porosus

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    Twelve estuarine crocodiles (6-51 kg) were fitted with recording back packs in order to study the longevity, frequency and daily/tidal rhythm of natural dives by crocodiles free-living in their familiar habitat. Despite disinterest shown by captive crocodiles in removing their jackets in tank trials, all but one of the seven crocodiles recaptured 5-16 days after release had shed their jackets and recorders. Results from the 9.75 kg animal showed that it had a prolonged emergence during each daylight low tide (basking?), that it dived mainly in daylight hours (feeding?), predominantly in the upper half of the tide and that most dives were of very short duration (1-5 minutes). Even the longest dive, 30 minutes, was well within the aerobic capabilities of a crocodile this size. Although these results are from a single animal, and may turn out to be quite atypical, if attachment problems are solved, the method has clear potential for revealing much about the daily activity patterns of free-ranging crocodiles and other animals
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