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Innovative Approaches to Emergency Medical Services Fellowship Challenges
Introduction: Since the development of an Accreditation Council of Graduate Medical Education (ACGME)-accredited emergency medical services (EMS) fellowship, there has been little published literature on effective methods of content delivery or training modalities. Here we explore a variety of innovative approaches to the development and revision of the EMS fellowship curriculum.Methods: Three academic, university-based ACGME-accredited EMS fellowship programs each implemented an innovative change to their existing training curricula. These changes included the following: a novel didactic curriculum delivery modality and evaluation; implementation of a distance education program to improve EMS fellows’ rural EMS experiences; and modification of an existing EMS fellowship curriculum to train a non-emergency medicine physician.Results: Changes made to each of the above EMS fellowship programs addressed unique challenges, demonstrating areas of success and promise for more generalized implementation of these curricula. Obstacles remain in tailoring the described curricula to the needs of each unique institution and system.Conclusion: Three separate curricula and program changes were implemented to overcome specific challenges and achieve educational goals. It is our hope that our shared experiences will enable others in addressing common barriers to teaching the EMS fellowship core content and share similar innovative approaches to educational challenges
Modulation of microglial activation by adenosine A2a receptor in animal models of perinatal brain injury
Neuroinflammation has a key role in the pathogenesis of perinatal brain injury. Caffeine, a nonspecific antagonist of adenosine receptors (ARs), is widely used to treat apnea of prematurity and has been linked to a decrease in the incidence of cerebral palsy in premature infants. The mechanisms explaining its neuroprotective effect have not yet been elucidated. The objective of this study was to characterize the expression of adenosine and ARs in two neonatal rat models of neuroinflammation and to determine the effect of A2aR blockade on microglial activation assessed through inflammatory cytokine gene expression. We have used two rat models of microglial activation: the gestational low protein diet (LPD) model, associated with chronic brain injury, and postnatal ibotenate intracerebral injections, responsible for acute excitotoxicity injury. Adenosine blood levels have been measured by Tandem Mass Spectrometry. The expression of ARs in vivo was assessed using qPCR and immunohistochemistry. In vivo models have been replicated in vitro on primary microglial cell cultures exposed to A2aR agonist CGS-21680 or antagonist SCH-58261. The effects of these treatments have been assessed on the M1/M2 cytokine expressions measured by RT-qPCR. LPD during pregnancy was associated with higher adenosine levels in pups at postnatal day 1 and 4. A2aR mRNA expression was significantly increased in both cortex and magnetically sorted microglial cells from LPD animals compared to controls. CD73 expression, responsible for extracellular production of brain adenosine, was significantly increased in LPD cortex and sorted microglia cells. Moreover, CD73 protein level was increased in ibotenate treated animals. In vitro experiments confirmed that LPD or control microglial cells exposed to ibotenate display an increased expression, at both protein and molecular levels, of A2aR and M1 markers (IL-1\u3b2, IL-6, iNOS, TNF\u3b1). This pro-inflammatory profile was significantly reduced by SCH-58261, which reduces M1 markers in both LPD and ibotenate-exposed cells, with no effect on control cells. In the same experimental conditions, a partial increased of M1 cytokines was observed in response to A2aR agonist CGS-21680. These results support the involvement of adenosine and particularly of its receptor A2aR in the regulation of microglia in two different animal models of neuroinflammation
New Relativistic Effects in the Dynamics of Nonlinear Hydrodynamical Waves
In Newtonian and relativistic hydrodynamics the Riemann problem consists of
calculating the evolution of a fluid which is initially characterized by two
states having different values of uniform rest-mass density, pressure and
velocity. When the fluid is allowed to relax, one of three possible
wave-patterns is produced, corresponding to the propagation in opposite
directions of two nonlinear hydrodynamical waves. New effects emerge in a
special relativistic Riemann problem when velocities tangential to the initial
discontinuity surface are present. We show that a smooth transition from one
wave-pattern to another can be produced by varying the initial tangential
velocities while otherwise maintaining the initial states unmodified. These
special relativistic effects are produced by the coupling through the
relativistic Lorentz factors and do not have a Newtonian counterpart.Comment: 4 pages, 5 figure
Mass-loaded spherical accretion flows
We have calculated the evolution of spherical accretion flows undergoing mass-loading from embedded clouds through either conduction or hydrodynamical ablation. We have observed the effect of varying the ratios of the mass-loading timescale and the cooling timescale to the ballistic crossing timescale through the mass-loading region.
We have also varied the ratio of the potential energy of a particle injected into the flow near the outer region of mass-loading to the temperature at which a minimum occurs in the cooling curve. The two types of mass-loading produce qualitatively different types of behaviour in the accretion flow, since mass-loading through conduction requires the ambient gas to be hot, whereas mass ablation from clumps occurs throughout the flow. Higher ratios of injected to accreted mass typically occur with hydrodynamical ablation, in agreement with previous work on wind-blown bubbles and supernova remnants. We find that mass-loading damps the radiative overstability of such flows, in agreement with our earlier work. If the mass-loading is high enough it can stabilize the accretion shock at a constant radius, yielding an almost isothermal subsonic post-shock flow. Such solutions may be relevant to cooling flows onto massive galaxies. Mass-loading can also lead to the formation of isolated shells of high temperature material, separated by gas at cooler temperatures
Some Remarks on the Neutrino Oscillation Phase in a Gravitational Field
The weak gravitational field expansion method to account for the
gravitationally induced neutrino oscillation effect is critically examined. It
is shown that the splitting of the neutrino phase into a ``kinematic'' and a
``gravitational'' phase is not always possible because the relativistic factor
modifies the particle interference phase splitting condition in a gravitational
field.Comment: 4 pages, no figure
Altered intra-nuclear organisation of heterochromatin and genes in ICF syndrome.
The ICF syndrome is a rare autosomal recessive disorder, the most common symptoms of which are immunodeficiency, facial anomalies and cytogenetic defects involving decondensation and instability of chromosome 1, 9 and 16 centromeric regions. ICF is also characterised by significant hypomethylation of the classical satellite DNA, the major constituent of the juxtacentromeric heterochromatin. Here we report the first attempt at analysing some of the defining genetic and epigenetic changes of this syndrome from a nuclear architecture perspective. In particular, we have compared in ICF (Type 1 and Type 2) and controls the large-scale organisation of chromosome 1 and 16 juxtacentromeric heterochromatic regions, their intra-nuclear positioning, and co-localisation with five specific genes (BTG2, CNN3, ID3, RGS1, F13A1), on which we have concurrently conducted expression and methylation analysis. Our investigations, carried out by a combination of molecular and cytological techniques, demonstrate the existence of specific and quantifiable differences in the genomic and nuclear organisation of the juxtacentromeric heterochromatin in ICF. DNA hypomethylation, previously reported to correlate with the decondensation of centromeric regions in metaphase described in these patients, appears also to correlate with the heterochromatin spatial configuration in interphase. Finally, our findings on the relative positioning of hypomethylated satellite sequences and abnormally expressed genes suggest a connection between disruption of long-range gene-heterochromatin associations and some of the changes in gene expression in ICF. Beyond its relevance to the ICF syndrome, by addressing fundamental principles of chromosome functional organisation within the cell nucleus, this work aims to contribute to the current debate on the epigenetic impact of nuclear architecture in development and disease
The general treatment of high/low energy particle interference phase in a gravitational field
The interference phase of the high energy mass neutrinos and the low energy
thermal neutrons in a gravitational field are studied. For the mass neutrinos,
we obtain that the phase calculated along the null is equivalent to the half
phase along the geodesic in the high energy limit, which means that the correct
relative phase of the mass neutrinos is either the null phase or the half
geodesic phase.
Further we point out the importance of the energy condition in calculating
the mass neutrino interference phase. Moreover, we apply the covariant phase to
the calculation of the thermal neutron interference phase, and obtain the
consistent result with that exploited in COW experiment.Comment: 14 pages, 1 figur
Action principle formulation for motion of extended bodies in General Relativity
We present an action principle formulation for the study of motion of an
extended body in General Relativity in the limit of weak gravitational field.
This gives the classical equations of motion for multipole moments of arbitrary
order coupling to the gravitational field. In particular, a new force due to
the octupole moment is obtained. The action also yields the gravitationally
induced phase shifts in quantum interference experiments due to the coupling of
all multipole moments.Comment: Revised version derives Octupole moment force. Some clarifications
and a reference added. To appear in Phys. Rev.
Paving the way toward autonomous shipping development for European Waters – The AUTOSHIP project
New developments in maritime industry include the design and operation of autonomous ships. The AUTOSHIP project is one initiative promoting the use of autonomous ships in European waters focusing on two specific use cases, a Short Sea Shipping (SSS) cargo vessel and an Inland Waterways (IWW) barge. The AUTOSHIP objectives include thorough regulatory, societal, financial, safety and security analyses for the two investigated use cases as well as the development of a novel framework and methods for the design of autonomous vessels. This objective is achieved with the support of a number of activities, including supply chain, regulatory, risk and gaps analyses. Some results and findings from these activities are presented in this paper. The results demonstrate that the supply chain analysis is important to understand the complex relationships between different partners and phases for the effective design of maritime autonomous systems. Furthermore, a number of regulatory gaps needs to be addressed for the wider adoption of the AUTOSHIP use cases. There is a number of essential hazards associated with each of the two use cases; measures to mitigate these hazards are presented
Assessment of a high-resolution central scheme for the solution of the relativistic hydrodynamics equations
We assess the suitability of a recent high-resolution central scheme
developed by Kurganov & Tadmor (2000) for the solution of the relativistic
hydrodynamics equations. The novelty of this approach relies on the absence of
Riemann solvers in the solution procedure. The computations we present are
performed in one and two spatial dimensions in Minkowski spacetime. Standard
numerical experiments such as shock tubes and the relativistic flat-faced step
test are performed. As an astrophysical application the article includes
two-dimensional simulations of the propagation of relativistic jets using both
Cartesian and cylindrical coordinates. The simulations reported clearly show
the capabilities of the numerical scheme to yield satisfactory results, with an
accuracy comparable to that obtained by the so-called high-resolution
shock-capturing schemes based upon Riemann solvers (Godunov-type schemes), even
well inside the ultrarelativistic regime. Such central scheme can be
straightforwardly applied to hyperbolic systems of conservation laws for which
the characteristic structure is not explicitly known, or in cases where the
exact solution of the Riemann problem is prohibitively expensive to compute
numerically. Finally, we present comparisons with results obtained using
various Godunov-type schemes as well as with those obtained using other
high-resolution central schemes which have recently been reported in the
literature.Comment: 14 pages, 12 figures, to appear in A&
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