2,864 research outputs found
The role of concomitant drugs in the aetiology of fatal heroin- and methadone- related overdose
Heroin and methadone poisoning are significant causes of death of young people in the United Kingdom. In a high proportion of these fatalities concomitant substances are also detected. This thesis is concerned with the significance of this observation and the hypothesis that these substances are risk factors for fatal heroin- and methadone-related overdose. A referential database was developed incorporating post-mortem toxicology data from 1,222 heroin and methadone overdose fatalities from around England and Wales. The most commonly detected concomitant drugs were ethanol, diazepam, temazepam, an additional opioid and cocaine. In the first of two studies, statistical models were derived, using multiple linear regression, to assess the potential effect of these concomitant substances on the lethality of heroin and methadone. Log-log and semi-log models were considered and regression coefficients were estimated by ordinary least squares. Ethanol blood concentrations were associated with significantly reduced blood levels of total morphine and methadone, consistent with a causal role for this substance. There was an absence of evidence of a similar effect for other commonly detected concomitants
The Unreasonable Effectiveness of Deep Features as a Perceptual Metric
While it is nearly effortless for humans to quickly assess the perceptual
similarity between two images, the underlying processes are thought to be quite
complex. Despite this, the most widely used perceptual metrics today, such as
PSNR and SSIM, are simple, shallow functions, and fail to account for many
nuances of human perception. Recently, the deep learning community has found
that features of the VGG network trained on ImageNet classification has been
remarkably useful as a training loss for image synthesis. But how perceptual
are these so-called "perceptual losses"? What elements are critical for their
success? To answer these questions, we introduce a new dataset of human
perceptual similarity judgments. We systematically evaluate deep features
across different architectures and tasks and compare them with classic metrics.
We find that deep features outperform all previous metrics by large margins on
our dataset. More surprisingly, this result is not restricted to
ImageNet-trained VGG features, but holds across different deep architectures
and levels of supervision (supervised, self-supervised, or even unsupervised).
Our results suggest that perceptual similarity is an emergent property shared
across deep visual representations.Comment: Accepted to CVPR 2018; Code and data available at
https://www.github.com/richzhang/PerceptualSimilarit
Backscattered Electron (BSE) Imaging in the Scanning Electron Microscope (SEM) - Measurement of Surface Layer Mass-Thickness
Sometimes, the sample to be examined in the SEM will consist of a compositionally non-uniform substrate that is covered by an approximately uniform surface layer. With a low enough incident beam energy, only the surface layer can be seen in the SEM image. The underlying structure can be seen in the secondary electron (SE) image if the range of the incident electrons is greater than twice the thickness of the surface film. In the backscattered electron (BSE) image the threshold energy is higher because the BSE detector is insensitive to slow electrons. The information depth in the BSE image was investigated experimentally as a function of incident energy and BSE detector position using test specimens in which an Al layer of thickness either 210 or 1,100 nm was deposited onto an aluminised Si wafer covered by a pattern of gold lines. It was estimated that a lower limit to the surface mass-thickness that can be measured using a solid-state BSE detector is ~ I0ÎĽg/cm2 (=40 nm of Al) for the BSE method, as compared with ~ 0.25 ÎĽg/cm2 (=1 nm of Al) for the low-loss electron method. There would seem to be no reason why measurements by the BSE method could not be carried out automatically in a computer-controlled SEM equipped with image analysis and using the standard BSE detector systems, to measure the mass-thickness of a surface layer
State Administrative Reorganization by Constitutional Revision
233 pagesThe last two sessions of Oregon's legislature bills have been introduced to provide for a constitutional convention. For some time there has existed a rather vague feeling of discontent with the Oregon constitution. Critics have pointed out useless and archaic provisions and the combination of the basic law, statutory law, and administrative regulation which appear in the constitution. These deficiencies may or may not be sufficient reason for calling a constitutional convention. It is not likely such a convention would confine itself to the deletion of anachronisms and to improve the whole constitution and the administrative structure of state government
2005-2006 Master Class - Jon Nakamatsu (Piano)
Jon Nakamatsu Performance (March 14, 2006) - Programhttps://spiral.lynn.edu/conservatory_masterclasses/1143/thumbnail.jp
Nephrotic syndrome and kidney failure due to immunocomplex-mediated renal damage in a patient with Waldenström's Macroglobulinemia: a case report
Recommended from our members
Equipment replacement prioritization measures : simulation and testing for a vehicle fleet
Oregon Department of Transportation (ODOT) Fleet Services manages a fleet that in 2008 included approximately 5,000 pieces of active equipment worth 390 million. Every biennium, a fixed budget is available to replace a certain amount of this equipment. This research evaluated various measures for establishing equipment replacement priorities.
A model was developed to simulate the operation of a single equipment class over time, including equipment replacement every two years. Five different equipment classes were simulated using ten measures for establishing replacement priorities. Historical data for these five different equipment classes (provided by ODOT) was used to define various simulation parameters. The effectiveness of each prioritization measure was evaluated using the cost per mile to operate the fleet over the simulated time period
- …