16,856 research outputs found
Amniotic Fluid Ingestion Enhances\ud Opioid-Mediated But Not\ud Nonopioid-Mediated Analgesia
Ingestion of amniotic fluid or placenta by rats has been shown to enhance several types of opioid-mediated analgesia: that induced by morphine, footshock, vaginal/cervical stimulation, and late pregnancy. This enhancement has also been blocked by administration of opioid antagonists. The present study was designed to examine further the specificity of the enhancement effect for opioid-mediated analgesia by testing for enhancement following administration of aspirin, a nonopioid analgesic. The formalin test was used as the pain threshold assay. Amniotic fluid or beef bouillon was administered by orogastric tube to rats that were treated either with morphine sulfate or saline. or pretreated with naltrexone, then treated with aspirin or vehicle. Both morphine and aspirin treatments produced analgesia. Amniotic fluid significantly enhanced the analgesia produced by morphine, but did not enhance the analgesia produced by aspirin, further suggesting that the enhancing effect of amniotic fluid ingestion is specific for opioid-mediated analgesia, such as that existing at the start of parturition
Saddle Points and Stark Ladders: Exact Calculations of Exciton Spectra in Superlattices
A new, exact method for calculating excitonic absorption in superlattices is
described. It is used to obtain high resolution spectra showing the saddle
point exciton feature near the top of the miniband. The evolution of this
feature is followed through a series of structures with increasing miniband
width. The Stark ladder of peaks produced by an axial electric field is
investigated, and it is shown that for weak fields the line shapes are strongly
modified by coupling to continuum states, taking the form of Fano resonances.
The calculated spectra, when suitably broadened, are found to be in good
agreement with experimental results.Comment: 9 pages Revtex v3.0, followed by 4 uuencoded postscript figures,
SISSA-CM-94-00
Background Independent Algebraic Structures in Closed String Field Theory
We construct a Batalin-Vilkovisky (BV) algebra on moduli spaces of Riemann
surfaces. This algebra is background independent in that it makes no reference
to a state space of a conformal field theory. Conformal theories define a
homomorphism of this algebra to the BV algebra of string functionals. The
construction begins with a graded-commutative free associative algebra \C
built from the vector space whose elements are orientable subspaces of moduli
spaces of punctured Riemann surfaces. The typical element here is a surface
with several connected components. The operation of sewing two
punctures with a full twist is shown to be an odd, second order derivation that
squares to zero. It follows that (\C, \Delta) is a Batalin-Vilkovisky
algebra. We introduce the odd operator , where
is the boundary operator. It is seen that , and that
consistent closed string vertices define a cohomology class of . This
cohomology class is used to construct a Lie algebra on a quotient space of
\C. This Lie algebra gives a manifestly background independent description of
a subalgebra of the closed string gauge algebra.Comment: phyzzx.tex, MIT-CTP-234
Multiplexed DNA-Modified Electrodes
We report the use of silicon chips with 16 DNA-modified electrodes (DME chips) utilizing DNA-mediated charge transport for multiplexed detection of DNA and DNA-binding protein targets. Four DNA sequences were simultaneously distinguished on a single DME chip with 4-fold redundancy, including one incorporating a single base mismatch. These chips also enabled investigation of the sequence-specific activity of the restriction enzyme Alu1. DME chips supported dense DNA monolayer formation with high reproducibility, as confirmed by statistical comparison to commercially available rod electrodes. The working electrode areas on the chips were reduced to 10 μm in diameter, revealing microelectrode behavior that is beneficial for high sensitivity and rapid kinetic analysis. These results illustrate how DME chips facilitate sensitive and selective detection of DNA and DNA-binding protein targets in a robust and internally standardized multiplexed format
A systematic review and economic evaluation of subcutaneous and sublingual allergen immunotherapy in adults and children with seasonal allergic rhinitis
© Queen’s Printer and Controller of HMSO 2013Severe allergic rhinitis uncontrolled by conventional medication can substantially affect quality of life. Immunotherapy involves administering increasing doses of a specific allergen, with the aim of reducing sensitivity and symptomatic reactions. Recent meta-analyses have concluded that both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are more effective than placebo in reducing symptoms. It is uncertain which route of administration is more effective and whether or not treatment is cost-effective.National Institute for Health Research Health Technology Assessment programm
Lichens of six vernal pools in Acadia National Park, ME, USA
Whereas lichen-habitat relations have been well-documented globally, literature on lichens of vernal pools is scant. We surveyed six vernal pools at Acadia National Park on Mount Desert Island, Maine, USA for their lichen diversity. Sixty-seven species were identified, including seven species that are new reports for Acadia National Park: Fuscidea arboricola, Hypogymnia incurvoides, Lepraria finkii, Phaeographis inusta, Ropalospora viridis, Usnea flammea, and Violella fucata. Five species are considered uncommon or only locally common in New England: Everniastrum catawbiense, Hypogymnia krogiae, Pseudevernia cladonia, Usnea flammea, and Usnea merrillii. This work represents the first survey of lichens from vernal pools in Acadia National Park and strongly suggests that previous efforts at documenting species at the Park have underestimated its species diversity. More work should be conducted to determine whether a unique assemblage of lichens occurs in association with this unique habitat type
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The activities and impact of personalisation in a UK business school
The aim of this study is to consider the activities and impact of Personalisation in a UK higher education setting. It will consider how personalisation has affected outputs in terms of progression, achievement, internship, enterprise project and international placement uptake within the Nottingham Business School at Nottingham Trent University.
The Methodology comprised of using qualitative and quantitative data. Semi-structured interviews were carried out with members of the Personalisation team and those in the delivery of Personalisation. The quantitative data pertains to outputs in terms of success rates, particularly with regard to when the Personalisation project began in 2015/16.
The findings suggest that the Personalisation process involves engagement, interaction and reflection to meet the needs and requirements of the learner, as well as providing them options. This contributes to success rates with the outputs, particularly when the Personalisation project began
Surface Divergences and Boundary Energies in the Casimir Effect
Although Casimir, or quantum vacuum, forces between distinct bodies, or
self-stresses of individual bodies, have been calculated by a variety of
different methods since 1948, they have always been plagued by divergences.
Some of these divergences are associated with the volume, and so may be more or
less unambiguously removed, while other divergences are associated with the
surface. The interpretation of these has been quite controversial. Particularly
mysterious is the contradiction between finite total self-energies and surface
divergences in the local energy density. In this paper we clarify the role of
surface divergences.Comment: 8 pages, 1 figure, submitted to proceedings of QFEXT0
Surface plasmon modes and the Casimir energy
We show the influence of surface plasmons on the Casimir effect between two
plane parallel metallic mirrors at arbitrary distances. Using the plasma model
to describe the optical response of the metal, we express the Casimir energy as
a sum of contributions associated with evanescent surface plasmon modes and
propagative cavity modes. In contrast to naive expectations, the plasmonic
modes contribution is essential at all distances in order to ensure the correct
result for the Casimir energy. One of the two plasmonic modes gives rise to a
repulsive contribution, balancing out the attractive contributions from
propagating cavity modes, while both contributions taken separately are much
larger than the actual value of the Casimir energy. This also suggests
possibilities to tailor the sign of the Casimir force via surface plasmons.Comment: 4 pages, 3 figures, revtex
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