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Tree of Life Synagogue Shooting in Pittsburgh: Preparedness, Prehospital Care, and Lessons Learned
On Saturday, October 27, 2018, a man with anti-Semitic motivations entered Tree of Life synagogue in the Squirrel Hill section of Pittsburgh, Pennsylvania; he had an AR-15 semi-automatic rifle and three handguns, opening fire upon worshippers. Eventually 11 civilians died at the scene and eight people sustained non-fatal injuries, including five police officers. Each person injured but alive at the scene received care at one of three local level-one trauma centers. The injured had wounds often seen in war-settings, with the signature of high velocity weaponry. We describe the scene response, specific elements of our hospital plans, the overall out-of-hospital preparedness in Pittsburgh, and the lessons learned
Nitrogen-Vacancy Ensemble Magnetometry Based on Pump Absorption
We demonstrate magnetic field sensing using an ensemble of nitrogen-vacancy
centers by recording the variation in the pump-light absorption due to the
spin-polarization dependence of the total ground state population. Using a 532
nm pump laser, we measure the absorption of native nitrogen-vacancy centers in
a chemical vapor deposited diamond placed in a resonant optical cavity. For a
laser pump power of 0.4 W and a cavity finesse of 45, we obtain a noise floor
of 100 nT/ spanning a bandwidth up to 125 Hz. We
project a photon shot-noise-limited sensitivity of 1
pT/ by optimizing the nitrogen-vacancy concentration and
the detection method.Comment: 7 pages and 5 figure
Towards Picogram Detection of Superparamagnetic Iron-Oxide Particles Using a Gradiometric Receive Coil
Superparamagnetic iron-oxide nanoparticles can be used in a variety of
medical applications like vascular or targeted imaging. Magnetic particle
imaging (MPI) is a promising tomographic imaging technique that allows
visualizing the 3D nanoparticle distribution concentration in a non-invasive
manner. The two main strengths of MPI are high temporal resolution and high
sensitivity. While the first has been proven in the assessment of dynamic
processes like cardiac imaging, it is unknown how far the detection limit of
MPI can be lowered. Within this work, we will present a highly sensitive
gradiometric receive-coil unit combined with a noise-matching network tailored
for the measurement of mice. The setup is capable of detecting 5 ng of iron in
vitro at 2.14 sec acquisition time. In terms of iron concentration we are able
to detect 156 {\mu}g/L marking the lowest value that has been reported for an
MPI scanner so far. In vivo MPI mouse images of a 512 ng bolus at 21.5 ms
acquisition time allow for capturing the flow of an intravenously injected
tracer through the heart of a mouse. Since it has been rather difficult to
compare detection limits across MPI publications we propose guidelines
improving the comparability of future MPI studies.Comment: 15 Pages, 7 Figures, V2: Changed the initials of Author Kannan M
Krishnan, added two citations, corrected typo
Functional MRI To Evaluate “Sense of Self” following Perforator Flap Breast Reconstruction
Background: Breast reconstruction is associated with high levels of patient satisfaction. Previous patient satisfaction studies have been subjective. This study utilizes functional magnetic resonance imaging (fMRI) to objectively evaluate “sense of self” following deep inferior epigastric perforator (DIEP) flap breast reconstruction in an attempt to better understand patient perception.
Methods: Prospective fMRI analysis was performed on four patients before and after delayed unilateral DIEP flap breast reconstruction, and on four patients after immediate unilateral DIEP flap breast reconstruction. Patients were randomly cued to palpate their natural breast, mastectomy site or breast reconstruction, and external silicone models. Three regions of interest (ROIs) associated with self-recognition were examined using a general linear model, and compared using a fixed effects and random effects ANOVA, respectively.
Results: In the delayed reconstruction group, activation of the ROIs was significantly lower at the mastectomy site compared to the natural breast (p<0.01). Ten months following reconstruction, activation of the ROIs in the reconstructed breast was not significantly different from that observed with natural breast palpation. In the immediate reconstruction group, palpation of the reconstructed breast was also similar to the natural breast. This activity was greater than that observed during palpation of external artificial models (p<0.01).
Conclusions: Similar activation patterns were observed during palpation of the reconstructed and natural breasts as compared to the non-reconstructed mastectomy site and artificial models. The cognitive process represented by this pattern may be a mechanism by which breast reconstruction improves self-perception, and thus patient satisfaction following mastectomy
Smart Chest X-ray Worklist Prioritization using Artificial Intelligence: A Clinical Workflow Simulation
The aim is to evaluate whether smart worklist prioritization by artificial
intelligence (AI) can optimize the radiology workflow and reduce report
turnaround times (RTAT) for critical findings in chest radiographs (CXRs).
Furthermore, we investigate a method to counteract the effect of false negative
predictions by AI -- resulting in an extremely and dangerously long RTAT, as
CXRs are sorted to the end of the worklist.
We developed a simulation framework that models the current workflow at a
university hospital by incorporating hospital specific CXR generation rates,
reporting rates and pathology distribution. Using this, we simulated the
standard worklist processing "first-in, first-out" (FIFO) and compared it with
a worklist prioritization based on urgency. Examination prioritization was
performed by the AI, classifying eight different pathological findings ranked
in descending order of urgency: pneumothorax, pleural effusion, infiltrate,
congestion, atelectasis, cardiomegaly, mass and foreign object. Furthermore, we
introduced an upper limit for the maximum waiting time, after which the highest
urgency is assigned to the examination.
The average RTAT for all critical findings was significantly reduced in all
Prioritization-simulations compared to the FIFO-simulation (e.g. pneumothorax:
35.6 min vs. 80.1 min; p ), while the maximum RTAT for most findings
increased at the same time (e.g. pneumothorax: 1293 min vs 890 min; p
). Our "upper limit" substantially reduced the maximum RTAT all
classes (e.g. pneumothorax: 979 min vs. 1293 min / 1178 min; p ).
Our simulations demonstrate that smart worklist prioritization by AI can
reduce the average RTAT for critical findings in CXRs while maintaining a small
maximum RTAT as FIFO
Application of Palladium-Mediated 18F-Fluorination to PET Radiotracer Development: Overcoming Hurdles to Translation
New chemistry methods for the synthesis of radiolabeled small molecules have the potential to impact clinical positron emission tomography (PET) imaging, if they can be successfully translated. However, progression of modern reactions from the stage of synthetic chemistry development to the preparation of radiotracer doses ready for use in human PET imaging is challenging and rare. Here we describe the process of and the successful translation of a modern palladium-mediated fluorination reaction to non-human primate (NHP) baboon PET imaging–an important milestone on the path to human PET imaging. The method, which transforms [18F]fluoride into an electrophilic fluorination reagent, provides access to aryl–18F bonds that would be challenging to synthesize via conventional radiochemistry methods.Chemistry and Chemical Biolog
Effect of Spatial Charge Inhomogeneity on 1/f Noise Behavior in Graphene
Scattering mechanisms in graphene are critical to understanding the limits of
signal-to-noise-ratios of unsuspended graphene devices. Here we present the
four-probe low frequency noise (1/f) characteristics in back-gated single layer
graphene (SLG) and bilayer graphene (BLG) samples. Contrary to the expected
noise increase with the resistance, the noise for SLG decreases near the Dirac
point, possibly due to the effects of the spatial charge inhomogeneity. For
BLG, a similar noise reduction near the Dirac point is observed, but with a
different gate dependence of its noise behavior. Some possible reasons for the
different noise behavior between SLG and BLG are discussed.Comment: 28 pages, 3 figures + 3 supplement figure
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