108 research outputs found

    Pre-hospital emergency nurse specialist's experiences in caring for patients with non-specific chief complaints in the ambulance - A qualitative interview study

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    Background: Pre-hospital emergency nurse (PEN) specialists are faced with patients presenting with non-specific chief complaints (NSC) to the emergency medical service (EMS) on a daily basis. These patients are often elderly and one in three has a serious condition and their acuity is not recognized. Objective: The aim of the current study was to explore PEN specialists' experiences in caring for patients presenting with non-specific chief complaints. Design: A qualitative study design with eleven individual interviews of PENs, between 2018 and 2020. Qualitative content analysis was used. Results: The analyses generated three categories including subcategories. The categories were "Unexplained suffering". "Systematic approach and experience enhances medical safety". "Organizational processes can be optimized". The relation between the categories compiled as 'In-depth systematic assessment is perceived to reduce suffering and increases patient safety. Conclusion: The PENs experiences in caring for patients presenting with non-specific chief complaints show that an in-depth systematic assessment may lead to a meaningful caring encounter which enables the identification of the cause of the chief complaint. Experience and a systematic approach were considered as essential to enhance medical safety. This could be strengthened through feedback on the nurse's care provided by care managers and employers. To optimize organizational processes, the development of the opportunity to convey the patient to different levels of care can be an important component.Peer reviewe

    GHRH secretion from a pancreatic neuroendocrine tumor causing gigantism in a patient with MEN1.

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    Summary: A male patient with a germline mutation in MEN1 presented at the age of 18 with classical features of gigantism. Previously, he had undergone resection of an insulin-secreting pancreatic neuroendocrine tumour (pNET) at the age of 10 years and had subtotal parathyroidectomy due to primary hyperparathyroidism at the age of 15 years. He was found to have significantly elevated serum IGF-1, GH, GHRH and calcitonin levels. Pituitary MRI showed an overall bulky gland with a 3 mm hypoechoic area. Abdominal MRI showed a 27 mm mass in the head of the pancreas and a 6 mm lesion in the tail. Lanreotide-Autogel 120 mg/month reduced GHRH by 45% and IGF-1 by 20%. Following pancreaticoduodenectomy, four NETs were identified with positive GHRH and calcitonin staining and Ki-67 index of 2% in the largest lesion. The pancreas tail lesion was not removed. Post-operatively, GHRH and calcitonin levels were undetectable, IGF-1 levels normalised and GH suppressed normally on glucose challenge. Post-operative fasting glucose and HbA1c levels have remained normal at the last check-up. While adolescent-onset cases of GHRH-secreting pNETs have been described, to the best of our knowledge, this is the first reported case of ectopic GHRH in a paediatric setting leading to gigantism in a patient with MEN1. Our case highlights the importance of distinguishing between pituitary and ectopic causes of gigantism, especially in the setting of MEN1, where paediatric somatotroph adenomas causing gigantism are extremely rare. Learning points: It is important to diagnose gigantism and its underlying cause (pituitary vs ectopic) early in order to prevent further growth and avoid unnecessary pituitary surgery. The most common primary tumour sites in ectopic acromegaly include the lung (53%) and the pancreas (34%) (1): 76% of patients with a pNET secreting GHRH showed a MEN1 mutation (1). Plasma GHRH testing is readily available in international laboratories and can be a useful diagnostic tool in distinguishing between pituitary acromegaly mediated by GH and ectopic acromegaly mediated by GHRH. Positive GHRH immunostaining in the NET tissue confirms the diagnosis. Distinguishing between pituitary (somatotroph) hyperplasia secondary to ectopic GHRH and pituitary adenoma is difficult and requires specialist neuroradiology input and consideration, especially in the MEN1 setting. It is important to note that the vast majority of GHRH-secreting tumours (lung, pancreas, phaeochromocytoma) are expected to be visible on cross-sectional imaging (median diameter 55 mm) (1). Therefore, we suggest that a chest X-ray and an abdominal ultrasound checking the adrenal glands and the pancreas should be included in the routine work-up of newly diagnosed acromegaly patients

    The trace left by signature-change-induced compactification

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    Recently, it has been shown that an infinite succession of classical signature changes (''signature oscillations'') can compactify and stabilize internal dimensions, and simultaneously leads, after a coarse graining type of average procedure, to an effective (''physical'') space-time geometry displaying the usual Lorentzian metric signature. Here, we consider a minimally coupled scalar field on such an oscillating background and study its effective dynamics. It turns out that the resulting field equation in four dimensions contains a coupling to some non-metric structure, the imprint of the ''microscopic'' signature oscillations on the effective properties of matter. In a multidimensional FRW model, this structure is identical to a massive scalar field evolving in its homogeneous mode.Comment: 15 pages, LaTeX, no figure

    Dilaton Contributions to the Cosmic Gravitational Wave Background

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    We consider the cosmological amplification of a metric perturbation propagating in a higher-dimensional Brans-Dicke background, including a non trivial dilaton evolution. We discuss the properties of the spectral energy density of the produced gravitons (as well as of the associated squeezing parameter), and we show that the present observational bounds on the graviton spectrum provide significant information on the dynamical evolution of the early universe.Comment: 26 pages, plain tex (to appear in Phys.Rev.D, 1 fig available from the authors upon req.

    Fast Algorithms For Josephson Junction Arrays : Bus--bars and Defects

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    We critically review the fast algorithms for the numerical study of two--dimensional Josephson junction arrays and develop the analogy of such systems with electrostatics. We extend these procedures to arrays with bus--bars and defects in the form of missing bonds. The role of boundaries and of the guage choice in determing the Green's function of the system is clarified. The extension of the Green's function approach to other situations is also discussed.Comment: Uuencoded 1 Revtex file (11 Pages), 3 Figures : Postscript Uuencode

    Accelerating Universes in String Theory via Field Redefinition

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    We study cosmological solutions in the effective heterotic string theory with α′\alpha'-correction terms in string frame. It is pointed out that the effective theory has an ambiguity via field redefinition and we analyze generalized effective theories due to this ambiguity. We restrict our analysis to the effective theories which give equations of motion of second order in the derivatives, just as "Galileon" field theory. This class of effective actions contains two free coupling constants. We find de Sitter solutions as well as the power-law expanding universes in our four-dimensional Einstein frame. The accelerated expanding universes are always the attractors in the present dynamical system.Comment: 22 pages, 3 figures, some additional formulae adde

    Scalar and Tensor Inhomogeneities from Dimensional Decoupling

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    We discuss some perturbative techniques suitable for the gauge-invariant treatment of the scalar and tensor inhomogeneities of an anisotropic and homogeneous background geometry whose spatial section naturally decomposes into the direct product of two maximally symmetric Eucledian manifolds, describing a general situation of dimensional decoupling in which dd external dimensions evolve (in conformal time) with scale factor a(η)a(\eta) and nn internal dimensions evolve with scale factor b(η)b(\eta). We analyze the growing mode problem which typically arises in contracting backgrounds and we focus our attention on the situation where the amplitude of the fluctuations not only depends on the external space-time but also on the internal spatial coordinates. In order to illustrate the possible relevance of this analysis we compute the gravity waves spectrum produced in some highly simplified model of cosmological evolution and we find that the spectral amplitude, whose magnitude can be constrained by the usual bounds applied to the stochastic gravity waves backgrounds, depends on the curvature scale at which the compactification occurs and also on the typical frequency of the internal excitations.Comment: 31 pages, Latex, DAMTP 96-92, UCM 96-04, to appear in Phys. Rev. D 55 (1997

    Dynamical Compactification, Standard Cosmology and the Accelerating Universe

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    A cosmological model based on Kaluza-Klein theory is studied. A metric, in which the scale factor of the compact space evolves as an inverse power of the radius of the observable universe, is constructed. The Freedmann-Robertson-Walker equations of standard four-dimensional cosmology are obtained precisely. The pressure in our universe is an effective pressure expressed in terms of the components of the higher dimensional energy-momentum tensor. In particular, this effective pressure could be negative and might therefore explain the acceleration of our present universe. A special feature of this model is that, for a suitable choice of the parameters of the metric, the higher dimensional gravitational coupling constant could be negative.Comment: 11 pages, uses revte

    Metric Perturbations in Dilaton-Driven Inflation

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    We compute the spectrum of scalar and tensor metric perturbations generated, as amplified vacuum fluctuations, during an epoch of dilaton-driven inflation of the type occurring naturally in string cosmology. In the tensor case the computation is straightforward while, in the scalar case, it is made delicate by the appearance of a growing mode in the familiar longitudinal gauge. In spite of this, a reliable perturbative calculation of perturbations far outside the horizon can be performed by resorting either to appropriate gauge invariant variables, or to a new coordinate system in which the growing mode can be "gauged down". The simple outcome of this complicated analysis is that both scalar and tensor perturbations exhibit nearly Planckian spectra, whose common "temperature" is related to some very basic parameters of the string-cosmology background.Comment: 34 pages, latex, no figure
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