2,889 research outputs found
An overview of the opioid crisis and analysis of standardized patient education
Opioids have been used for the treatment of pain for hundreds of years, but recent increases in availability and drug potency have created an epidemic of opioid addiction and overdose. Between 2000 and 2015, opioid-related drug overdoses contributed to a reduction of 0.21 years to life expectancy in the United States. More recently, the Centers for Disease Control and Prevention estimated that opioids were involved in 47,600 overdose deaths in 2017 alone, with an increasing proportion of those deaths coming from heroin and synthetic opioids. The United States government has been responding to the opioid crisis in large part by dedicating resources to the treatment of opioid overdose victims with naloxone and the rehabilitation of opioid addicts. The reactive nature of this approach, while greatly beneficial to the portion of the United States population already addicted to opioids, does little to prevent patients from becoming addicted to drugs in the first place. Teaching patients when and how to use prescriptions safely could prove to be a more viable strategy in addressing not only the opioid crisis but in preventing similar future public health crises involving prescription drugs
Growth, properties and magnetism of CaKFe4As4
CaKFe4As4 is a new stoichiometric member of the iron-based superconductors (FeSCs) which is a superconductor below 35 K. In this thesis I outline how single crystals of this material are grown for the first time and their basic properties. I discuss how substituting Ni or Co for Fe stabilizes antiferromagnetism at the expense of superconductivity. I reveal how the crystal structure of CaKFe4As4 leads to the observed hedgehog spin-vortex crystal magnetic order instead of the magnetic structures adopted by the other FeSCs. Finally, I propose a series of new magneto-elastic couplings in this new magnetic structure
Genetic Techniques and Circuit Analysis
Reaching an understanding of how neuronal circuits work and what they compute is a fundamental aim of neuroscience, perhaps even the most fundamental. We have to both establish the connections between cell types and reversibly manipulate their activity cell-typeselectively. Such work sounds in principle straight-forward, but it has been difficult to achieve. This has now all changed. There has been a quite remarkable development of genetic techniques published in the last years, so that the topic of “Genetic techniques and circuit analysis ” covered by the articles in this Special Issue is truly flourishing. The extremely easy applicability of the channelrhodopsin-2 system (ChR2) in diverse animals and circuit settings has been a phenomenal breakthrough and captured the imagination of the neuroscience community (see, for example, Adamantidis et al., 2009; Han et al., 2009). A major advantage of ChR2 is that precise patterns of activation can be delivered cell-type selectively
Lack of superconductivity in the phase diagram of single-crystalline Eu(Fe1-xCox)2As2 grown by transition metal arsenide flux
The interplay of magnetism and superconductivity (SC) has been a focus of
interest in condensed matter physics for decades. EuFe2As2 has been identified
as a potential platform to investigate interactions between structural,
magnetic, electronic effects as well as coexistence of magnetism and SC with
similar transition temperatures. However, there are obvious inconsistencies in
the reported phase diagrams of Eu(Fe1-xCox)2As2 crystals grown by different
methods. For transition metal arsenide (TMA)-flux-grown crystals, even the
existence of SC is open for dispute. Here we re-examine the phase diagram of
single-crystalline Eu(Fe1-xCox)2As2 grown by TMA flux. We found that the
lattice parameter c shrinks linearly with Co doping, almost twice as fast as
that of the tin-flux-grown crystals. With Co doping, the spin-density-wave
(SDW) order of Fe sublattice is quickly suppressed, being detected only up to x
= 0.08. The magnetic ordering temperature of the Eu2+ sublattice (TEu) shows a
systematic evolution with Co doping, first going down and reaching a minimum at
x = 0.08, then increasing continuously up to x = 0.24. Over the whole
composition range investigated, no signature of SC is observed.Comment: 24 pages, 7 figure
Upgrade of the Minos+ Experiment Data Acquisition for the High Energy NuMI Beam Run
The Minos+ experiment is an extension of the Minos experiment at a higher
energy and more intense neutrino beam, with the data collection having begun in
the fall of 2013. The neutrino beam is provided by the Neutrinos from the Main
Injector (NuMI) beam-line at Fermi National Accelerator Laboratory (Fermilab).
The detector apparatus consists of two main detectors, one underground at
Fermilab and the other in Soudan, Minnesota with the purpose of studying
neutrino oscillations at a base line of 735 km. The original data acquisition
system has been running for several years collecting data from NuMI, but with
the extended run from 2013, parts of the system needed to be replaced due to
obsolescence, reliability problems, and data throughput limitations.
Specifically, we have replaced the front-end readout controllers, event
builder, and data acquisition computing and trigger processing farms with
modern, modular and reliable devices with few single points of failure. The new
system is based on gigabit Ethernet TCP/IP communication to implement the event
building and concatenation of data from many front-end VME readout crates. The
simplicity and partitionability of the new system greatly eases the debugging
and diagnosing process. The new system improves throughput by about a factor of
three compared to the old system, up to 800 megabits per second, and has proven
robust and reliable in the current run.Comment: 3 page
NMR Study of the New Magnetic Superconductor CaK(Fe$0.951Ni0.049)4As4: Microscopic Coexistence of Hedgehog Spin-vortex Crystal and Superconductivity
Coexistence of a new-type antiferromagnetic (AFM) state, the so-called
hedgehog spin-vortex crystal (SVC), and superconductivity (SC) is evidenced by
As nuclear magnetic resonance study on single-crystalline
CaK(FeNi)As. The hedgehog SVC order is clearly
demonstrated by the direct observation of the internal magnetic induction along
the axis at the As1 site (close to K) and a zero net internal magnetic
induction at the As2 site (close to Ca) below an AFM ordering temperature
52 K. The nuclear spin-lattice relaxation rate 1/ shows
a distinct decrease below 10 K, providing also unambiguous
evidence for the microscopic coexistence. Furthermore, based on the analysis of
the 1/ data, the hedgehog SVC-type spin correlations are found to be
enhanced below 150 K in the paramagnetic state. These results
indicate the hedgehog SVC-type spin correlations play an important role for the
appearance of SC in the new magnetic superconductor.Comment: 5 pages, 4 figures, accepted for publication in Phys. Rev. B rapid
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