3,918 research outputs found
Using MicroPET Imaging in Quantitative Verification of Acupuncture Effect in Ischemia Stroke Treatment
While acupuncture has survived several thousand years’ evolution of medical practice, its function still remains as a myth from the view point of modern medicine. Our goal in this paper is to quantitatively understand the function of acupuncture in ischemia stroke treatment. We carried out a comparative study using the Sprague Dawley rat animal model. We induced the focal cerebral ischemia in the rats using the middle cerebral artery occlusion (MCAO) procedure. For each rat from the real acupuncture group (n = 40), sham acupoint treatment group (n = 54), and blank control group (n = 16), we acquired 3-D FDG-microPET images at baseline, after MCAO, and after treatment (i.e., real acupuncture, sham acupoint treatment, or resting according to the group assignment), respectively. After verifying that the injured area is in the right hemisphere of the cerebral cortex in the brain by using magnetic resonance imaging(MRI) and triphenyl tetrazolium cchloride (TTC)-staining, we directly compared the glucose metabolism in the right hemisphere of each rat. We carried out t-test and permutation test on the image data. Both tests demonstrated that acupuncture had a more positive effect than non-acupoint stimulus and blank control (P < 0.025) in increasing the glucose metabolic level in the stroke-injured area in the brain, while there was no statistically significant difference between non-acupoint stimulus and blank control (P>0.15). The immediate positive effect of acupuncture over sham acupoint treatment and blank control is verified using our experiments. The long-term benefit of acupuncture needs to be further studied
Rare case of magnetic Ag ion: double perovskite CsKAgF
Normally or transition metals are in a low-spin state. Here using
first-principles calculations, we report on a rare case of a high-spin =1
magnetic state for the Ag ion in the double perovskite
CsKAgF. We also explored a possibility of a conventional low-spin
=0 ground state and find an associated tetragonal distortion to be 0.29
{\AA}. However, the lattice elastic energy cost and the Hund exchange loss
exceed the e crystal-field energy gain, thus making the low-spin
tetragonal structure less favorable than the high-spin cubic structure. We
conclude that the compact perovskite structure of CsKAgF is an
important factor in stabilizing the unusual high-spin ground state of
Ag.Comment: 6 pages, 6 figures, accepted for publication in PR
Progressive amorphization of GeSbTe phase-change material under electron beam irradiation
Fast and reversible phase transitions in chalcogenide phase-change materials
(PCMs), in particular, Ge-Sb-Te compounds, are not only of fundamental
interests, but also make PCMs based random access memory (PRAM) a leading
candidate for non-volatile memory and neuromorphic computing devices. To RESET
the memory cell, crystalline Ge-Sb-Te has to undergo phase transitions firstly
to a liquid state and then to an amorphous state, corresponding to an abrupt
change in electrical resistance. In this work, we demonstrate a progressive
amorphization process in GeSb2Te4 thin films under electron beam irradiation on
transmission electron microscope (TEM). Melting is shown to be completely
absent by the in situ TEM experiments. The progressive amorphization process
resembles closely the cumulative crystallization process that accompanies a
continuous change in electrical resistance. Our work suggests that if
displacement forces can be implemented properly, it should be possible to
emulate symmetric neuronal dynamics by using PCMs
GROUND REACTION FORCE ANALYSIS FOR DIFFERENT FEET POSITION IN BASKETBALL DEFENSIVE-SHUFFLE
INTRODUCTION: There are several steps for defending in basketball competition. Defender must shuffle toward lateral rear to defend. We want to understand how the different defensive steps works when defence. The purpose of this study was to collect the ground reaction force while defender shuffling toward lateral rear to find the differences of the different feet position, which we can find the optimal strategy to stop opponent cutting and moving
IMPRESS: Evaluating the Resilience of Imperceptible Perturbations Against Unauthorized Data Usage in Diffusion-Based Generative AI
Diffusion-based image generation models, such as Stable Diffusion or DALL-E
2, are able to learn from given images and generate high-quality samples
following the guidance from prompts. For instance, they can be used to create
artistic images that mimic the style of an artist based on his/her original
artworks or to maliciously edit the original images for fake content. However,
such ability also brings serious ethical issues without proper authorization
from the owner of the original images. In response, several attempts have been
made to protect the original images from such unauthorized data usage by adding
imperceptible perturbations, which are designed to mislead the diffusion model
and make it unable to properly generate new samples. In this work, we introduce
a perturbation purification platform, named IMPRESS, to evaluate the
effectiveness of imperceptible perturbations as a protective measure. IMPRESS
is based on the key observation that imperceptible perturbations could lead to
a perceptible inconsistency between the original image and the
diffusion-reconstructed image, which can be used to devise a new optimization
strategy for purifying the image, which may weaken the protection of the
original image from unauthorized data usage (e.g., style mimicking, malicious
editing). The proposed IMPRESS platform offers a comprehensive evaluation of
several contemporary protection methods, and can be used as an evaluation
platform for future protection methods.Comment: 21 pages, 11 figures, 9 tables. Accepted by NeurIPS 202
The decay and the mixing
We study the and reactions, and pay attention to the different sources of isospin
violation and mixing of and resonances where these
resonances are dynamically generated from meson-meson interaction. We find that
the main reason of isospin violation is the isospin breaking in the meson-meson
transition matrices, and the other source is that the loops involving kaons
in the production mechanism provide a source of isospin violation because they
do not cancel by the different mass of the charged and neutral kaons. We obtain
a branching ratio for production of the order of .
Future experiments can address this problem and the production rate and shape
of the mass distribution will definitely help to better understand
the nature of scalar resonances.Comment: 12 pages, 4 figure
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