295 research outputs found
Analysis of increased public access to naloxone as a method to control the recent fentanyl epidemic
The opioid fentanyl is becoming an increasingly popular drug of abuse across the United States. With a potency up to 100 times greater than the common opioid morphine, fentanyl use can easily lead to overdoses. This is especially true as fentanyl is increasingly found mixed into other illicit drugs without users’ knowledge. However, there exists an antidote for opioid overdoses called naloxone. Naloxone is a pure antagonist at μ-opioid receptors in the brain and produces little known side-effects. Recently, the FDA has approved naloxone delivery devices designed for individuals without medical training, making naloxone layperson friendly. Under today’s policy, naloxone is a prescription medication. This means physicians must write a prescription for take-home naloxone or issue a standing order allowing other healthcare professionals to distribute naloxone. However, there are little federal laws governing naloxone as most of the statutes discussing naloxone access and administration are determined by individual states. For example, only some states allow physicians to prescribe naloxone to non-patients. Additionally, many states have differing laws regarding criminal liabilities for physicians who prescribe the drug and for laypersons who administer the drug. In the U.S. there exists a dilemma with naloxone, as topics ranging from public policy to insurance coverage are controversial. With increasing information on fentanyl and naloxone being published, the U.S. is currently looking into the idea of making naloxone more accessible as a way to reduce overdose deaths
Analysis of increased public access to naloxone as a method to control the recent fentanyl epidemic
The opioid fentanyl is becoming an increasingly popular drug of abuse across the United States. With a potency up to 100 times greater than the common opioid morphine, fentanyl use can easily lead to overdoses. This is especially true as fentanyl is increasingly found mixed into other illicit drugs without users’ knowledge. However, there exists an antidote for opioid overdoses called naloxone. Naloxone is a pure antagonist at μ-opioid receptors in the brain and produces little known side-effects. Recently, the FDA has approved naloxone delivery devices designed for individuals without medical training, making naloxone layperson friendly. Under today’s policy, naloxone is a prescription medication. This means physicians must write a prescription for take-home naloxone or issue a standing order allowing other healthcare professionals to distribute naloxone. However, there are little federal laws governing naloxone as most of the statutes discussing naloxone access and administration are determined by individual states. For example, only some states allow physicians to prescribe naloxone to non-patients. Additionally, many states have differing laws regarding criminal liabilities for physicians who prescribe the drug and for laypersons who administer the drug. In the U.S. there exists a dilemma with naloxone, as topics ranging from public policy to insurance coverage are controversial. With increasing information on fentanyl and naloxone being published, the U.S. is currently looking into the idea of making naloxone more accessible as a way to reduce overdose deaths
Spectral shifting strongly constrains molecular cloud disruption by radiation pressure on dust
To test the hypothesis that radiation pressure from star
clusters acting on dust is the dominant feedback agent disrupting the largest
star-forming molecular clouds and thus regulating the star-formation process.
We perform multi-frequency, 3D, RT calculations including
scattering, absorption, and re-emission to longer wavelengths for clouds with
masses of -M, with embedded clusters and a star
formation efficiencies of 0.009%-91%, and varying maximum grain sizes up to
200m. We calculate the ratio between radiative force and gravity to
determine whether radiation pressure can disrupt clouds. We
find that radiation acting on dust almost never disrupts star-forming clouds.
UV and optical photons to which the cloud is optically thick do not scatter
much. Instead, they quickly get absorbed and re-emitted by at thermal
wavelengths. As the cloud is typically optically thin to far-IR radiation, it
promptly escapes, depositing little momentum. The resulting spectrum is more
narrowly peaked than the corresponding Planck function with an extended tail at
longer wavelengths. As the opacity drops significantly across the sub-mm and
mm, the resulting radiative force is even smaller than for the corresponding
single-temperature black body. The force from radiation pressure falls below
the strength of gravitational attraction by an order of magnitude or more for
either Milky Way or starbust conditions. For unrealistically large maximum
grain sizes, and star formation efficiencies far exceeding 50% do we find that
the strength of radiation pressure can exceed gravity. We
conclude that radiation pressure acting on dust does not disrupt star-forming
molecular clouds in any Local Group galaxies. Radiation pressure thus appears
unlikely to regulate the star-formation process on either local or global
scales.Comment: 20 pages, 17 figure
When H II Regions are Complicated: Considering Perturbations from Winds, Radiation Pressure, and Other Effects
We explore to what extent simple algebraic models can be used to describe H
II regions when winds, radiation pressure, gravity and photon breakout are
included. We a) develop algebraic models to describe the expansion of
photoionised H II regions under the influence of gravity and accretion in
power-law density fields with , b) determine when terms
describing winds, radiation pressure, gravity and photon breakout become
significant enough to affect the dynamics of the H II region where , and
c) solve these expressions for a set of physically-motivated conditions. We
find that photoionisation feedback from massive stars is the principal mode of
feedback on molecular cloud scales, driving accelerating outflows from
molecular clouds in cases where the peaked density structure around young
massive stars is considered at radii between 0.1 and 10-100 pc. Under a
large range of conditions the effect of winds and radiation on the dynamics of
H II regions is around 10% of the contribution from photoionisation. The effect
of winds and radiation pressure are most important at high densities, either
close to the star or in very dense clouds such as those in the Central
Molecular Zone of the Milky Way. Out to 0.1 pc they are the principal
drivers of the H II region. Lower metallicities make the relative effect of
photoionisation even stronger as the ionised gas temperature is higher.Comment: 20 pages, 13 figures, accepted by MNRA
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