127 research outputs found

    THE ANCIENT DRUG OPIUM

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    The use of papaver somniferum (from the Latin fero ferre = ‘tobear/bring’ and somnium = ‘sleep’) as a narcotic, goes backto the 13th century BC. The works of ancient authors such asDioscorides, Celsus, Galen, Theophrastus and Pliny the Elderprovide us with detailed information about the morphology of theplant, its processing and the administration of the drug.1 Theseauthors make it clear that opium was mainly employed as anodyneand narcotic but they also documented its use as a drug inthe treatment of a variety of ailments, either as one of manyingredients in a medicinal recipe or as the main ingredient.Modern botanical and pharmaceutical analysis of the plant and itsactive ingredients provide us with some surprising conclusionsregarding its effectiveness in the treatment of the medical conditionsfor which it was prescribed in the 1st and 2nd century

    Dynamics of Elastic Excitable Media

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    The Burridge-Knopoff model of earthquake faults with viscous friction is equivalent to a van der Pol-FitzHugh-Nagumo model for excitable media with elastic coupling. The lubricated creep-slip friction law we use in the Burridge-Knopoff model describes the frictional sliding dynamics of a range of real materials. Low-dimensional structures including synchronized oscillations and propagating fronts are dominant, in agreement with the results of laboratory friction experiments. Here we explore the dynamics of fronts in elastic excitable media.Comment: Int. J. Bifurcation and Chaos, to appear (1999

    Self-Assembling Ice Membranes on Europa: Brinicle Properties, Field Examples, and Possible Energetic Systems in Icy Ocean Worlds

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    Brinicles are self-assembling tubular ice membrane structures, centimeters to meters in length, found beneath sea ice in the polar regions of Earth. We discuss how the properties of brinicles make them of possible importance for chemistry in cold environments-including that of life's emergence-and we consider their formation in icy ocean world. We argue that the non-ice composition of the ice on Europa and Enceladus will vary spatially due to thermodynamic and mechanical properties that serve to separate and fractionate brines and solid materials. The specifics of the composition and dynamics of both the ice and the ocean in these worlds remain poorly constrained. We demonstrate through calculations using FREZCHEM that sulfate likely fractionates out of accreting ice in Europa and Enceladus, and thus that an exogenous origin of sulfate observed on Europa's surface need not preclude additional endogenous sulfate in Europa's ocean. We suggest that, like hydrothermal vents on Earth, brinicles in icy ocean worlds constitute ideal places where ecosystems of organisms might be found

    Lip tape therapy in patients with a cleft lip – a report on eight cases

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    INTRODUCTION: Lip tape therapy or lip taping is a widely used tissue approximation technique in cleft lip babies. Various tapes have been tested and used worldwide. Allergic reactions and skin irritation are the most common problems encountered. Tension force across the tape cannot be consistently applied. Cost is also an obstacle to adopting lip tape therapy, particularly in developing countries. AIM: A study was undertaken to evaluate a different tape, “physio tape”, which has never been used for lip approximation in cleft lip babies. METHOD: Eight babies were available for this study, which was conducted over a six-week period (Ethical Approval number 33/2013). Standardised pre- and post-treatment recordings were made with a digital camera and soft tissue analysis was carried out with Cliniview software. RESULTS: All participants showed a reduction in cleft size ranging from 9.1mm to 36.7mm at the vermillion end of the cleft. Caregivers had no difficulty with the lip tape procedure and generally no untoward or allergic reactions were reported. CONCLUSION: On the basis of the positive results of this investigation, it is recommended that this method of lip tape therapy be used on all babies born with a cleft lip. It is affordable, simple to use and should facilitate the surgical repair.http://www.sada.co.za2015-03-30am201

    Exploding Chemical Gardens: A Phase-Change Clock Reaction.

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    Chemical gardens and clock reactions are two of the best-known demonstration reactions in chemistry. Until now these have been separate categories. We have discovered that a chemical garden confined to two dimensions is a clock reaction involving a phase change, so that after a reproducible and controllable induction period it explodes

    Safety, tolerability and clinical implementation of 'ready-to-use' 68gallium-DOTA0-Tyr3-octreotide (68Ga-DOTATOC) (SomaKIT TOC) for injection in patients diagnosed with gastroenteropancreatic neuroendocrine tumours (GEP-NETs)

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    BACKGROUND: 68Ga-DOTA0-Tyr3-octreotide (68Ga-DOTATOC) positron emission tomography-CT (PET-CT) has superior diagnostic performance compared to the licensed tracer OctreoScan single photon emission CT-CT in patients with gastroenteropancreatic neuroendocrine tumours (GEP-NETs). A new preparation of 68Ga-DOTATOC using a new 'ready-to-use' 68Ga-DOTATOC formulation for injection has been developed (68Ga-DOTATOC (SomaKIT TOC)). OBJECTIVES: This study aimed to assess the safety and tolerability of 68Ga-DOTATOC (SomaKIT TOC) and evaluate the feasibility and robustness of implementing it in a NET clinical imaging service. METHODS: A first-in-human phase I/II multicentre, open-label study of a single dose of 68Ga-DOTATOC (SomaKIT TOC) 2 MBq/kg±10% (range 100-200 MBq) in patients with biopsy-proven grade 1-2 GEP-NETs. PET-CT was performed post injection. Patients were followed up for 28 days. We next implemented this new synthesis methodology in a clinical service assessed over 11 months. RESULTS: Twenty consenting patients were recruited; 14 males, 6 females; mean (SD) age 58 years (12); NET grade 1 (70%), grade 2 (30%); and 75% with stage IV disease. Twelve patients experienced at least one adverse event (AE) during the study with no grade 3-4 toxicities. Only four AEs were classified as possibly (headache (n=1; 4%), nausea (1; 4%)) or probably (dysgeusia (1; 4%), paraesthesia (1; 4%)) related to the study preparation. One hundred thirteen vials of 68Ga-DOTATOC (SomaKIT TOC) were synthesised with the 'kit' over a period of 11 months for clinical utility. Only 2/113 vials (1.77%) were rejected. CONCLUSIONS: The new ready-to-use preparation of 68Ga-DOTATOC (SomaKIT TOC) for injection was safe and well tolerated. This has led to the world's first (EMA) licensed 68Ga-DOTATOC (SomaKIT TOC) radiopharmaceutical for the utility of PET imaging in patients with NETs. This preparation can be robustly implemented into routine clinical practice

    Global Diffusion in a Realistic Three-Dimensional Time-Dependent Nonturbulent Fluid Flow

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    We introduce and study the first model of an experimentally realizable three-dimensional time-dependent nonturbulent fluid flow to display the phenomenon of global diffusion of passive-scalar particles at arbitrarily small values of the nonintegrable perturbation. This type of chaotic advection, termed {\it resonance-induced diffusion\/}, is generic for a large class of flows.Comment: 4 pages, uuencoded compressed postscript file, to appear in Phys. Rev. Lett. Also available on the WWW from http://formentor.uib.es/~julyan/, or on paper by reques

    Nonlinear Dynamics of the Perceived Pitch of Complex Sounds

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    We apply results from nonlinear dynamics to an old problem in acoustical physics: the mechanism of the perception of the pitch of sounds, especially the sounds known as complex tones that are important for music and speech intelligibility

    Bailout Embeddings and Neutrally Buoyant Particles in Three-Dimensional Flows

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    We use the bailout embeddings of three-dimensional volume-preserving maps to study qualitatively the dy- namics of small spherical neutrally buoyant impurities suspended in a time-periodic incompressible fluid flow. The accumulation of impurities in tubular vortical structures, the detachment of particles from fluid trajectories near hyperbolic invariant lines, and the formation of nontrivial three-dimensional structures in the distribution of particles are predicted.Comment: 4 pages, 3 figure

    Dynamics of a small neutrally buoyant sphere in a fluid and targeting in Hamiltonian systems

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    We show that, even in the most favorable case, the motion of a small spherical tracer suspended in a fluid of the same density may differ from the corresponding motion of an ideal passive particle. We demonstrate furthermore how its dynamics may be applied to target trajectories in Hamiltonian systems.Comment: See home page http://lec.ugr.es/~julya
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